diff options
Diffstat (limited to 'drivers/spi/spi.c')
| -rw-r--r-- | drivers/spi/spi.c | 3414 |
1 files changed, 2369 insertions, 1045 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 9a7def7c3237..e25df9990f82 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -4,52 +4,54 @@ // Copyright (C) 2005 David Brownell // Copyright (C) 2008 Secret Lab Technologies Ltd. -#include <linux/kernel.h> -#include <linux/device.h> -#include <linux/init.h> +#include <linux/acpi.h> #include <linux/cache.h> -#include <linux/dma-mapping.h> +#include <linux/clk/clk-conf.h> +#include <linux/delay.h> +#include <linux/device.h> #include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/export.h> +#include <linux/gpio/consumer.h> +#include <linux/highmem.h> +#include <linux/idr.h> +#include <linux/init.h> +#include <linux/ioport.h> +#include <linux/kernel.h> +#include <linux/kthread.h> +#include <linux/mod_devicetable.h> #include <linux/mutex.h> #include <linux/of_device.h> #include <linux/of_irq.h> -#include <linux/clk/clk-conf.h> -#include <linux/slab.h> -#include <linux/mod_devicetable.h> -#include <linux/spi/spi.h> -#include <linux/spi/spi-mem.h> -#include <linux/of_gpio.h> -#include <linux/pm_runtime.h> +#include <linux/percpu.h> +#include <linux/platform_data/x86/apple.h> #include <linux/pm_domain.h> +#include <linux/pm_runtime.h> #include <linux/property.h> -#include <linux/export.h> +#include <linux/ptp_clock_kernel.h> #include <linux/sched/rt.h> +#include <linux/slab.h> +#include <linux/spi/offload/types.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi-mem.h> #include <uapi/linux/sched/types.h> -#include <linux/delay.h> -#include <linux/kthread.h> -#include <linux/ioport.h> -#include <linux/acpi.h> -#include <linux/highmem.h> -#include <linux/idr.h> -#include <linux/platform_data/x86/apple.h> #define CREATE_TRACE_POINTS #include <trace/events/spi.h> +EXPORT_TRACEPOINT_SYMBOL(spi_transfer_start); +EXPORT_TRACEPOINT_SYMBOL(spi_transfer_stop); #include "internals.h" -static DEFINE_IDR(spi_master_idr); +static DEFINE_IDR(spi_controller_idr); static void spidev_release(struct device *dev) { struct spi_device *spi = to_spi_device(dev); - /* spi controllers may cleanup for released devices */ - if (spi->controller->cleanup) - spi->controller->cleanup(spi); - spi_controller_put(spi->controller); kfree(spi->driver_override); + free_percpu(spi->pcpu_statistics); kfree(spi); } @@ -63,7 +65,7 @@ modalias_show(struct device *dev, struct device_attribute *a, char *buf) if (len != -ENODEV) return len; - return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias); + return sysfs_emit(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias); } static DEVICE_ATTR_RO(modalias); @@ -72,29 +74,11 @@ static ssize_t driver_override_store(struct device *dev, const char *buf, size_t count) { struct spi_device *spi = to_spi_device(dev); - const char *end = memchr(buf, '\n', count); - const size_t len = end ? end - buf : count; - const char *driver_override, *old; - - /* We need to keep extra room for a newline when displaying value */ - if (len >= (PAGE_SIZE - 1)) - return -EINVAL; - - driver_override = kstrndup(buf, len, GFP_KERNEL); - if (!driver_override) - return -ENOMEM; + int ret; - device_lock(dev); - old = spi->driver_override; - if (len) { - spi->driver_override = driver_override; - } else { - /* Emptry string, disable driver override */ - spi->driver_override = NULL; - kfree(driver_override); - } - device_unlock(dev); - kfree(old); + ret = driver_set_override(dev, &spi->driver_override, buf, count); + if (ret) + return ret; return count; } @@ -106,12 +90,57 @@ static ssize_t driver_override_show(struct device *dev, ssize_t len; device_lock(dev); - len = snprintf(buf, PAGE_SIZE, "%s\n", spi->driver_override ? : ""); + len = sysfs_emit(buf, "%s\n", spi->driver_override ? : ""); device_unlock(dev); return len; } static DEVICE_ATTR_RW(driver_override); +static struct spi_statistics __percpu *spi_alloc_pcpu_stats(struct device *dev) +{ + struct spi_statistics __percpu *pcpu_stats; + + if (dev) + pcpu_stats = devm_alloc_percpu(dev, struct spi_statistics); + else + pcpu_stats = alloc_percpu_gfp(struct spi_statistics, GFP_KERNEL); + + if (pcpu_stats) { + int cpu; + + for_each_possible_cpu(cpu) { + struct spi_statistics *stat; + + stat = per_cpu_ptr(pcpu_stats, cpu); + u64_stats_init(&stat->syncp); + } + } + return pcpu_stats; +} + +static ssize_t spi_emit_pcpu_stats(struct spi_statistics __percpu *stat, + char *buf, size_t offset) +{ + u64 val = 0; + int i; + + for_each_possible_cpu(i) { + const struct spi_statistics *pcpu_stats; + u64_stats_t *field; + unsigned int start; + u64 inc; + + pcpu_stats = per_cpu_ptr(stat, i); + field = (void *)pcpu_stats + offset; + do { + start = u64_stats_fetch_begin(&pcpu_stats->syncp); + inc = u64_stats_read(field); + } while (u64_stats_fetch_retry(&pcpu_stats->syncp, start)); + val += inc; + } + return sysfs_emit(buf, "%llu\n", val); +} + #define SPI_STATISTICS_ATTRS(field, file) \ static ssize_t spi_controller_##field##_show(struct device *dev, \ struct device_attribute *attr, \ @@ -119,7 +148,7 @@ static ssize_t spi_controller_##field##_show(struct device *dev, \ { \ struct spi_controller *ctlr = container_of(dev, \ struct spi_controller, dev); \ - return spi_statistics_##field##_show(&ctlr->statistics, buf); \ + return spi_statistics_##field##_show(ctlr->pcpu_statistics, buf); \ } \ static struct device_attribute dev_attr_spi_controller_##field = { \ .attr = { .name = file, .mode = 0444 }, \ @@ -130,47 +159,43 @@ static ssize_t spi_device_##field##_show(struct device *dev, \ char *buf) \ { \ struct spi_device *spi = to_spi_device(dev); \ - return spi_statistics_##field##_show(&spi->statistics, buf); \ + return spi_statistics_##field##_show(spi->pcpu_statistics, buf); \ } \ static struct device_attribute dev_attr_spi_device_##field = { \ .attr = { .name = file, .mode = 0444 }, \ .show = spi_device_##field##_show, \ } -#define SPI_STATISTICS_SHOW_NAME(name, file, field, format_string) \ -static ssize_t spi_statistics_##name##_show(struct spi_statistics *stat, \ +#define SPI_STATISTICS_SHOW_NAME(name, file, field) \ +static ssize_t spi_statistics_##name##_show(struct spi_statistics __percpu *stat, \ char *buf) \ { \ - unsigned long flags; \ - ssize_t len; \ - spin_lock_irqsave(&stat->lock, flags); \ - len = sprintf(buf, format_string, stat->field); \ - spin_unlock_irqrestore(&stat->lock, flags); \ - return len; \ + return spi_emit_pcpu_stats(stat, buf, \ + offsetof(struct spi_statistics, field)); \ } \ SPI_STATISTICS_ATTRS(name, file) -#define SPI_STATISTICS_SHOW(field, format_string) \ +#define SPI_STATISTICS_SHOW(field) \ SPI_STATISTICS_SHOW_NAME(field, __stringify(field), \ - field, format_string) + field) -SPI_STATISTICS_SHOW(messages, "%lu"); -SPI_STATISTICS_SHOW(transfers, "%lu"); -SPI_STATISTICS_SHOW(errors, "%lu"); -SPI_STATISTICS_SHOW(timedout, "%lu"); +SPI_STATISTICS_SHOW(messages); +SPI_STATISTICS_SHOW(transfers); +SPI_STATISTICS_SHOW(errors); +SPI_STATISTICS_SHOW(timedout); -SPI_STATISTICS_SHOW(spi_sync, "%lu"); -SPI_STATISTICS_SHOW(spi_sync_immediate, "%lu"); -SPI_STATISTICS_SHOW(spi_async, "%lu"); +SPI_STATISTICS_SHOW(spi_sync); +SPI_STATISTICS_SHOW(spi_sync_immediate); +SPI_STATISTICS_SHOW(spi_async); -SPI_STATISTICS_SHOW(bytes, "%llu"); -SPI_STATISTICS_SHOW(bytes_rx, "%llu"); -SPI_STATISTICS_SHOW(bytes_tx, "%llu"); +SPI_STATISTICS_SHOW(bytes); +SPI_STATISTICS_SHOW(bytes_rx); +SPI_STATISTICS_SHOW(bytes_tx); #define SPI_STATISTICS_TRANSFER_BYTES_HISTO(index, number) \ SPI_STATISTICS_SHOW_NAME(transfer_bytes_histo##index, \ "transfer_bytes_histo_" number, \ - transfer_bytes_histo[index], "%lu") + transfer_bytes_histo[index]) SPI_STATISTICS_TRANSFER_BYTES_HISTO(0, "0-1"); SPI_STATISTICS_TRANSFER_BYTES_HISTO(1, "2-3"); SPI_STATISTICS_TRANSFER_BYTES_HISTO(2, "4-7"); @@ -189,7 +214,7 @@ SPI_STATISTICS_TRANSFER_BYTES_HISTO(14, "16384-32767"); SPI_STATISTICS_TRANSFER_BYTES_HISTO(15, "32768-65535"); SPI_STATISTICS_TRANSFER_BYTES_HISTO(16, "65536+"); -SPI_STATISTICS_SHOW(transfers_split_maxsize, "%lu"); +SPI_STATISTICS_SHOW(transfers_split_maxsize); static struct attribute *spi_dev_attrs[] = { &dev_attr_modalias.attr, @@ -281,47 +306,46 @@ static const struct attribute_group spi_controller_statistics_group = { .attrs = spi_controller_statistics_attrs, }; -static const struct attribute_group *spi_master_groups[] = { +static const struct attribute_group *spi_controller_groups[] = { &spi_controller_statistics_group, NULL, }; -void spi_statistics_add_transfer_stats(struct spi_statistics *stats, - struct spi_transfer *xfer, - struct spi_controller *ctlr) +static void spi_statistics_add_transfer_stats(struct spi_statistics __percpu *pcpu_stats, + struct spi_transfer *xfer, + struct spi_message *msg) { - unsigned long flags; int l2len = min(fls(xfer->len), SPI_STATISTICS_HISTO_SIZE) - 1; + struct spi_statistics *stats; if (l2len < 0) l2len = 0; - spin_lock_irqsave(&stats->lock, flags); + get_cpu(); + stats = this_cpu_ptr(pcpu_stats); + u64_stats_update_begin(&stats->syncp); - stats->transfers++; - stats->transfer_bytes_histo[l2len]++; + u64_stats_inc(&stats->transfers); + u64_stats_inc(&stats->transfer_bytes_histo[l2len]); - stats->bytes += xfer->len; - if ((xfer->tx_buf) && - (xfer->tx_buf != ctlr->dummy_tx)) - stats->bytes_tx += xfer->len; - if ((xfer->rx_buf) && - (xfer->rx_buf != ctlr->dummy_rx)) - stats->bytes_rx += xfer->len; + u64_stats_add(&stats->bytes, xfer->len); + if (spi_valid_txbuf(msg, xfer)) + u64_stats_add(&stats->bytes_tx, xfer->len); + if (spi_valid_rxbuf(msg, xfer)) + u64_stats_add(&stats->bytes_rx, xfer->len); - spin_unlock_irqrestore(&stats->lock, flags); + u64_stats_update_end(&stats->syncp); + put_cpu(); } -EXPORT_SYMBOL_GPL(spi_statistics_add_transfer_stats); -/* modalias support makes "modprobe $MODALIAS" new-style hotplug work, +/* + * modalias support makes "modprobe $MODALIAS" new-style hotplug work, * and the sysfs version makes coldplug work too. */ - -static const struct spi_device_id *spi_match_id(const struct spi_device_id *id, - const struct spi_device *sdev) +static const struct spi_device_id *spi_match_id(const struct spi_device_id *id, const char *name) { while (id->name[0]) { - if (!strcmp(sdev->modalias, id->name)) + if (!strcmp(name, id->name)) return id; id++; } @@ -332,11 +356,23 @@ const struct spi_device_id *spi_get_device_id(const struct spi_device *sdev) { const struct spi_driver *sdrv = to_spi_driver(sdev->dev.driver); - return spi_match_id(sdrv->id_table, sdev); + return spi_match_id(sdrv->id_table, sdev->modalias); } EXPORT_SYMBOL_GPL(spi_get_device_id); -static int spi_match_device(struct device *dev, struct device_driver *drv) +const void *spi_get_device_match_data(const struct spi_device *sdev) +{ + const void *match; + + match = device_get_match_data(&sdev->dev); + if (match) + return match; + + return (const void *)spi_get_device_id(sdev)->driver_data; +} +EXPORT_SYMBOL_GPL(spi_get_device_match_data); + +static int spi_match_device(struct device *dev, const struct device_driver *drv) { const struct spi_device *spi = to_spi_device(dev); const struct spi_driver *sdrv = to_spi_driver(drv); @@ -354,12 +390,12 @@ static int spi_match_device(struct device *dev, struct device_driver *drv) return 1; if (sdrv->id_table) - return !!spi_match_id(sdrv->id_table, spi); + return !!spi_match_id(sdrv->id_table, spi->modalias); return strcmp(spi->modalias, drv->name) == 0; } -static int spi_uevent(struct device *dev, struct kobj_uevent_env *env) +static int spi_uevent(const struct device *dev, struct kobj_uevent_env *env) { const struct spi_device *spi = to_spi_device(dev); int rc; @@ -371,62 +407,66 @@ static int spi_uevent(struct device *dev, struct kobj_uevent_env *env) return add_uevent_var(env, "MODALIAS=%s%s", SPI_MODULE_PREFIX, spi->modalias); } -struct bus_type spi_bus_type = { - .name = "spi", - .dev_groups = spi_dev_groups, - .match = spi_match_device, - .uevent = spi_uevent, -}; -EXPORT_SYMBOL_GPL(spi_bus_type); - - -static int spi_drv_probe(struct device *dev) +static int spi_probe(struct device *dev) { const struct spi_driver *sdrv = to_spi_driver(dev->driver); struct spi_device *spi = to_spi_device(dev); + struct fwnode_handle *fwnode = dev_fwnode(dev); int ret; ret = of_clk_set_defaults(dev->of_node, false); if (ret) return ret; - if (dev->of_node) { + if (is_of_node(fwnode)) spi->irq = of_irq_get(dev->of_node, 0); - if (spi->irq == -EPROBE_DEFER) - return -EPROBE_DEFER; - if (spi->irq < 0) - spi->irq = 0; - } + else if (is_acpi_device_node(fwnode) && spi->irq < 0) + spi->irq = acpi_dev_gpio_irq_get(to_acpi_device_node(fwnode), 0); + if (spi->irq == -EPROBE_DEFER) + return dev_err_probe(dev, spi->irq, "Failed to get irq\n"); + if (spi->irq < 0) + spi->irq = 0; - ret = dev_pm_domain_attach(dev, true); + ret = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON | + PD_FLAG_DETACH_POWER_OFF); if (ret) return ret; - ret = sdrv->probe(spi); - if (ret) - dev_pm_domain_detach(dev, true); + if (sdrv->probe) + ret = sdrv->probe(spi); return ret; } -static int spi_drv_remove(struct device *dev) +static void spi_remove(struct device *dev) { const struct spi_driver *sdrv = to_spi_driver(dev->driver); - int ret; - - ret = sdrv->remove(to_spi_device(dev)); - dev_pm_domain_detach(dev, true); - return ret; + if (sdrv->remove) + sdrv->remove(to_spi_device(dev)); } -static void spi_drv_shutdown(struct device *dev) +static void spi_shutdown(struct device *dev) { - const struct spi_driver *sdrv = to_spi_driver(dev->driver); + if (dev->driver) { + const struct spi_driver *sdrv = to_spi_driver(dev->driver); - sdrv->shutdown(to_spi_device(dev)); + if (sdrv->shutdown) + sdrv->shutdown(to_spi_device(dev)); + } } +const struct bus_type spi_bus_type = { + .name = "spi", + .dev_groups = spi_dev_groups, + .match = spi_match_device, + .uevent = spi_uevent, + .probe = spi_probe, + .remove = spi_remove, + .shutdown = spi_shutdown, +}; +EXPORT_SYMBOL_GPL(spi_bus_type); + /** * __spi_register_driver - register a SPI driver * @owner: owner module of the driver to register @@ -439,19 +479,51 @@ int __spi_register_driver(struct module *owner, struct spi_driver *sdrv) { sdrv->driver.owner = owner; sdrv->driver.bus = &spi_bus_type; - if (sdrv->probe) - sdrv->driver.probe = spi_drv_probe; - if (sdrv->remove) - sdrv->driver.remove = spi_drv_remove; - if (sdrv->shutdown) - sdrv->driver.shutdown = spi_drv_shutdown; + + /* + * For Really Good Reasons we use spi: modaliases not of: + * modaliases for DT so module autoloading won't work if we + * don't have a spi_device_id as well as a compatible string. + */ + if (sdrv->driver.of_match_table) { + const struct of_device_id *of_id; + + for (of_id = sdrv->driver.of_match_table; of_id->compatible[0]; + of_id++) { + const char *of_name; + + /* Strip off any vendor prefix */ + of_name = strnchr(of_id->compatible, + sizeof(of_id->compatible), ','); + if (of_name) + of_name++; + else + of_name = of_id->compatible; + + if (sdrv->id_table) { + const struct spi_device_id *spi_id; + + spi_id = spi_match_id(sdrv->id_table, of_name); + if (spi_id) + continue; + } else { + if (strcmp(sdrv->driver.name, of_name) == 0) + continue; + } + + pr_warn("SPI driver %s has no spi_device_id for %s\n", + sdrv->driver.name, of_id->compatible); + } + } + return driver_register(&sdrv->driver); } EXPORT_SYMBOL_GPL(__spi_register_driver); /*-------------------------------------------------------------------------*/ -/* SPI devices should normally not be created by SPI device drivers; that +/* + * SPI devices should normally not be created by SPI device drivers; that * would make them board-specific. Similarly with SPI controller drivers. * Device registration normally goes into like arch/.../mach.../board-YYY.c * with other readonly (flashable) information about mainboard devices. @@ -466,9 +538,9 @@ static LIST_HEAD(board_list); static LIST_HEAD(spi_controller_list); /* - * Used to protect add/del opertion for board_info list and - * spi_controller list, and their matching process - * also used to protect object of type struct idr + * Used to protect add/del operation for board_info list and + * spi_controller list, and their matching process also used + * to protect object of type struct idr. */ static DEFINE_MUTEX(board_lock); @@ -502,13 +574,19 @@ struct spi_device *spi_alloc_device(struct spi_controller *ctlr) return NULL; } - spi->master = spi->controller = ctlr; + spi->pcpu_statistics = spi_alloc_pcpu_stats(NULL); + if (!spi->pcpu_statistics) { + kfree(spi); + spi_controller_put(ctlr); + return NULL; + } + + spi->controller = ctlr; spi->dev.parent = &ctlr->dev; spi->dev.bus = &spi_bus_type; spi->dev.release = spidev_release; - spi->cs_gpio = -ENOENT; - - spin_lock_init(&spi->statistics.lock); + spi->mode = ctlr->buswidth_override_bits; + spi->num_chipselect = 1; device_initialize(&spi->dev); return spi; @@ -517,71 +595,142 @@ EXPORT_SYMBOL_GPL(spi_alloc_device); static void spi_dev_set_name(struct spi_device *spi) { - struct acpi_device *adev = ACPI_COMPANION(&spi->dev); + struct device *dev = &spi->dev; + struct fwnode_handle *fwnode = dev_fwnode(dev); - if (adev) { - dev_set_name(&spi->dev, "spi-%s", acpi_dev_name(adev)); + if (is_acpi_device_node(fwnode)) { + dev_set_name(dev, "spi-%s", acpi_dev_name(to_acpi_device_node(fwnode))); + return; + } + + if (is_software_node(fwnode)) { + dev_set_name(dev, "spi-%pfwP", fwnode); return; } dev_set_name(&spi->dev, "%s.%u", dev_name(&spi->controller->dev), - spi->chip_select); + spi_get_chipselect(spi, 0)); +} + +/* + * Zero(0) is a valid physical CS value and can be located at any + * logical CS in the spi->chip_select[]. If all the physical CS + * are initialized to 0 then It would be difficult to differentiate + * between a valid physical CS 0 & an unused logical CS whose physical + * CS can be 0. As a solution to this issue initialize all the CS to -1. + * Now all the unused logical CS will have -1 physical CS value & can be + * ignored while performing physical CS validity checks. + */ +#define SPI_INVALID_CS ((s8)-1) + +static inline int spi_dev_check_cs(struct device *dev, + struct spi_device *spi, u8 idx, + struct spi_device *new_spi, u8 new_idx) +{ + u8 cs, cs_new; + u8 idx_new; + + cs = spi_get_chipselect(spi, idx); + for (idx_new = new_idx; idx_new < new_spi->num_chipselect; idx_new++) { + cs_new = spi_get_chipselect(new_spi, idx_new); + if (cs == cs_new) { + dev_err(dev, "chipselect %u already in use\n", cs_new); + return -EBUSY; + } + } + return 0; } static int spi_dev_check(struct device *dev, void *data) { struct spi_device *spi = to_spi_device(dev); struct spi_device *new_spi = data; + int status, idx; - if (spi->controller == new_spi->controller && - spi->chip_select == new_spi->chip_select) - return -EBUSY; + if (spi->controller == new_spi->controller) { + for (idx = 0; idx < spi->num_chipselect; idx++) { + status = spi_dev_check_cs(dev, spi, idx, new_spi, 0); + if (status) + return status; + } + } return 0; } -/** - * spi_add_device - Add spi_device allocated with spi_alloc_device - * @spi: spi_device to register - * - * Companion function to spi_alloc_device. Devices allocated with - * spi_alloc_device can be added onto the spi bus with this function. - * - * Return: 0 on success; negative errno on failure - */ -int spi_add_device(struct spi_device *spi) +static void spi_cleanup(struct spi_device *spi) +{ + if (spi->controller->cleanup) + spi->controller->cleanup(spi); +} + +static int __spi_add_device(struct spi_device *spi) { - static DEFINE_MUTEX(spi_add_lock); struct spi_controller *ctlr = spi->controller; struct device *dev = ctlr->dev.parent; - int status; + int status, idx; + u8 cs; - /* Chipselects are numbered 0..max; validate. */ - if (spi->chip_select >= ctlr->num_chipselect) { - dev_err(dev, "cs%d >= max %d\n", spi->chip_select, - ctlr->num_chipselect); - return -EINVAL; + if (spi->num_chipselect > SPI_DEVICE_CS_CNT_MAX) { + dev_err(dev, "num_cs %d > max %d\n", spi->num_chipselect, + SPI_DEVICE_CS_CNT_MAX); + return -EOVERFLOW; } + for (idx = 0; idx < spi->num_chipselect; idx++) { + /* Chipselects are numbered 0..max; validate. */ + cs = spi_get_chipselect(spi, idx); + if (cs >= ctlr->num_chipselect) { + dev_err(dev, "cs%d >= max %d\n", spi_get_chipselect(spi, idx), + ctlr->num_chipselect); + return -EINVAL; + } + } + + /* + * Make sure that multiple logical CS doesn't map to the same physical CS. + * For example, spi->chip_select[0] != spi->chip_select[1] and so on. + */ + if (!spi_controller_is_target(ctlr)) { + for (idx = 0; idx < spi->num_chipselect; idx++) { + status = spi_dev_check_cs(dev, spi, idx, spi, idx + 1); + if (status) + return status; + } + } + + /* Initialize unused logical CS as invalid */ + for (idx = spi->num_chipselect; idx < SPI_DEVICE_CS_CNT_MAX; idx++) + spi_set_chipselect(spi, idx, SPI_INVALID_CS); + /* Set the bus ID string */ spi_dev_set_name(spi); - /* We need to make sure there's no other device with this + /* + * We need to make sure there's no other device with this * chipselect **BEFORE** we call setup(), else we'll trash - * its configuration. Lock against concurrent add() calls. + * its configuration. */ - mutex_lock(&spi_add_lock); - status = bus_for_each_dev(&spi_bus_type, NULL, spi, spi_dev_check); - if (status) { - dev_err(dev, "chipselect %d already in use\n", - spi->chip_select); - goto done; + if (status) + return status; + + /* Controller may unregister concurrently */ + if (IS_ENABLED(CONFIG_SPI_DYNAMIC) && + !device_is_registered(&ctlr->dev)) { + return -ENODEV; } - if (ctlr->cs_gpios) - spi->cs_gpio = ctlr->cs_gpios[spi->chip_select]; + if (ctlr->cs_gpiods) { + u8 cs; - /* Drivers may modify this initial i/o setup, but will + for (idx = 0; idx < spi->num_chipselect; idx++) { + cs = spi_get_chipselect(spi, idx); + spi_set_csgpiod(spi, idx, ctlr->cs_gpiods[cs]); + } + } + + /* + * Drivers may modify this initial i/o setup, but will * normally rely on the device being setup. Devices * using SPI_CS_HIGH can't coexist well otherwise... */ @@ -589,19 +738,42 @@ int spi_add_device(struct spi_device *spi) if (status < 0) { dev_err(dev, "can't setup %s, status %d\n", dev_name(&spi->dev), status); - goto done; + return status; } /* Device may be bound to an active driver when this returns */ status = device_add(&spi->dev); - if (status < 0) + if (status < 0) { dev_err(dev, "can't add %s, status %d\n", dev_name(&spi->dev), status); - else + spi_cleanup(spi); + } else { dev_dbg(dev, "registered child %s\n", dev_name(&spi->dev)); + } -done: - mutex_unlock(&spi_add_lock); + return status; +} + +/** + * spi_add_device - Add spi_device allocated with spi_alloc_device + * @spi: spi_device to register + * + * Companion function to spi_alloc_device. Devices allocated with + * spi_alloc_device can be added onto the SPI bus with this function. + * + * Return: 0 on success; negative errno on failure + */ +int spi_add_device(struct spi_device *spi) +{ + struct spi_controller *ctlr = spi->controller; + int status; + + /* Set the bus ID string */ + spi_dev_set_name(spi); + + mutex_lock(&ctlr->add_lock); + status = __spi_add_device(spi); + mutex_unlock(&ctlr->add_lock); return status; } EXPORT_SYMBOL_GPL(spi_add_device); @@ -626,7 +798,8 @@ struct spi_device *spi_new_device(struct spi_controller *ctlr, struct spi_device *proxy; int status; - /* NOTE: caller did any chip->bus_num checks necessary. + /* + * NOTE: caller did any chip->bus_num checks necessary. * * Also, unless we change the return value convention to use * error-or-pointer (not NULL-or-pointer), troubleshootability @@ -639,20 +812,26 @@ struct spi_device *spi_new_device(struct spi_controller *ctlr, WARN_ON(strlen(chip->modalias) >= sizeof(proxy->modalias)); - proxy->chip_select = chip->chip_select; + /* Use provided chip-select for proxy device */ + spi_set_chipselect(proxy, 0, chip->chip_select); + proxy->max_speed_hz = chip->max_speed_hz; proxy->mode = chip->mode; proxy->irq = chip->irq; - strlcpy(proxy->modalias, chip->modalias, sizeof(proxy->modalias)); + strscpy(proxy->modalias, chip->modalias, sizeof(proxy->modalias)); proxy->dev.platform_data = (void *) chip->platform_data; proxy->controller_data = chip->controller_data; proxy->controller_state = NULL; + /* + * By default spi->chip_select[0] will hold the physical CS number, + * so set bit 0 in spi->cs_index_mask. + */ + proxy->cs_index_mask = BIT(0); - if (chip->properties) { - status = device_add_properties(&proxy->dev, chip->properties); + if (chip->swnode) { + status = device_add_software_node(&proxy->dev, chip->swnode); if (status) { - dev_err(&ctlr->dev, - "failed to add properties to '%s': %d\n", + dev_err(&ctlr->dev, "failed to add software node to '%s': %d\n", chip->modalias, status); goto err_dev_put; } @@ -660,14 +839,12 @@ struct spi_device *spi_new_device(struct spi_controller *ctlr, status = spi_add_device(proxy); if (status < 0) - goto err_remove_props; + goto err_dev_put; return proxy; -err_remove_props: - if (chip->properties) - device_remove_properties(&proxy->dev); err_dev_put: + device_remove_software_node(&proxy->dev); spi_dev_put(proxy); return NULL; } @@ -682,16 +859,22 @@ EXPORT_SYMBOL_GPL(spi_new_device); */ void spi_unregister_device(struct spi_device *spi) { + struct fwnode_handle *fwnode; + if (!spi) return; - if (spi->dev.of_node) { - of_node_clear_flag(spi->dev.of_node, OF_POPULATED); - of_node_put(spi->dev.of_node); + fwnode = dev_fwnode(&spi->dev); + if (is_of_node(fwnode)) { + of_node_clear_flag(to_of_node(fwnode), OF_POPULATED); + of_node_put(to_of_node(fwnode)); + } else if (is_acpi_device_node(fwnode)) { + acpi_device_clear_enumerated(to_acpi_device_node(fwnode)); } - if (ACPI_COMPANION(&spi->dev)) - acpi_device_clear_enumerated(ACPI_COMPANION(&spi->dev)); - device_unregister(&spi->dev); + device_remove_software_node(&spi->dev); + device_del(&spi->dev); + spi_cleanup(spi); + put_device(&spi->dev); } EXPORT_SYMBOL_GPL(spi_unregister_device); @@ -727,7 +910,6 @@ static void spi_match_controller_to_boardinfo(struct spi_controller *ctlr, * * The board info passed can safely be __initdata ... but be careful of * any embedded pointers (platform_data, etc), they're copied as-is. - * Device properties are deep-copied though. * * Return: zero on success, else a negative error code. */ @@ -747,12 +929,6 @@ int spi_register_board_info(struct spi_board_info const *info, unsigned n) struct spi_controller *ctlr; memcpy(&bi->board_info, info, sizeof(*info)); - if (info->properties) { - bi->board_info.properties = - property_entries_dup(info->properties); - if (IS_ERR(bi->board_info.properties)) - return PTR_ERR(bi->board_info.properties); - } mutex_lock(&board_lock); list_add_tail(&bi->list, &board_list); @@ -767,28 +943,184 @@ int spi_register_board_info(struct spi_board_info const *info, unsigned n) /*-------------------------------------------------------------------------*/ -static void spi_set_cs(struct spi_device *spi, bool enable) +/* Core methods for SPI resource management */ + +/** + * spi_res_alloc - allocate a spi resource that is life-cycle managed + * during the processing of a spi_message while using + * spi_transfer_one + * @spi: the SPI device for which we allocate memory + * @release: the release code to execute for this resource + * @size: size to alloc and return + * @gfp: GFP allocation flags + * + * Return: the pointer to the allocated data + * + * This may get enhanced in the future to allocate from a memory pool + * of the @spi_device or @spi_controller to avoid repeated allocations. + */ +static void *spi_res_alloc(struct spi_device *spi, spi_res_release_t release, + size_t size, gfp_t gfp) +{ + struct spi_res *sres; + + sres = kzalloc(sizeof(*sres) + size, gfp); + if (!sres) + return NULL; + + INIT_LIST_HEAD(&sres->entry); + sres->release = release; + + return sres->data; +} + +/** + * spi_res_free - free an SPI resource + * @res: pointer to the custom data of a resource + */ +static void spi_res_free(void *res) { - if (spi->mode & SPI_CS_HIGH) + struct spi_res *sres = container_of(res, struct spi_res, data); + + WARN_ON(!list_empty(&sres->entry)); + kfree(sres); +} + +/** + * spi_res_add - add a spi_res to the spi_message + * @message: the SPI message + * @res: the spi_resource + */ +static void spi_res_add(struct spi_message *message, void *res) +{ + struct spi_res *sres = container_of(res, struct spi_res, data); + + WARN_ON(!list_empty(&sres->entry)); + list_add_tail(&sres->entry, &message->resources); +} + +/** + * spi_res_release - release all SPI resources for this message + * @ctlr: the @spi_controller + * @message: the @spi_message + */ +static void spi_res_release(struct spi_controller *ctlr, struct spi_message *message) +{ + struct spi_res *res, *tmp; + + list_for_each_entry_safe_reverse(res, tmp, &message->resources, entry) { + if (res->release) + res->release(ctlr, message, res->data); + + list_del(&res->entry); + + kfree(res); + } +} + +/*-------------------------------------------------------------------------*/ +#define spi_for_each_valid_cs(spi, idx) \ + for (idx = 0; idx < spi->num_chipselect; idx++) \ + if (!(spi->cs_index_mask & BIT(idx))) {} else + +static inline bool spi_is_last_cs(struct spi_device *spi) +{ + u8 idx; + bool last = false; + + spi_for_each_valid_cs(spi, idx) { + if (spi->controller->last_cs[idx] == spi_get_chipselect(spi, idx)) + last = true; + } + return last; +} + +static void spi_toggle_csgpiod(struct spi_device *spi, u8 idx, bool enable, bool activate) +{ + /* + * Historically ACPI has no means of the GPIO polarity and + * thus the SPISerialBus() resource defines it on the per-chip + * basis. In order to avoid a chain of negations, the GPIO + * polarity is considered being Active High. Even for the cases + * when _DSD() is involved (in the updated versions of ACPI) + * the GPIO CS polarity must be defined Active High to avoid + * ambiguity. That's why we use enable, that takes SPI_CS_HIGH + * into account. + */ + if (is_acpi_device_node(dev_fwnode(&spi->dev))) + gpiod_set_value_cansleep(spi_get_csgpiod(spi, idx), !enable); + else + /* Polarity handled by GPIO library */ + gpiod_set_value_cansleep(spi_get_csgpiod(spi, idx), activate); + + if (activate) + spi_delay_exec(&spi->cs_setup, NULL); + else + spi_delay_exec(&spi->cs_inactive, NULL); +} + +static void spi_set_cs(struct spi_device *spi, bool enable, bool force) +{ + bool activate = enable; + u8 idx; + + /* + * Avoid calling into the driver (or doing delays) if the chip select + * isn't actually changing from the last time this was called. + */ + if (!force && (enable == spi_is_last_cs(spi)) && + (spi->controller->last_cs_index_mask == spi->cs_index_mask) && + (spi->controller->last_cs_mode_high == (spi->mode & SPI_CS_HIGH))) + return; + + trace_spi_set_cs(spi, activate); + + spi->controller->last_cs_index_mask = spi->cs_index_mask; + for (idx = 0; idx < SPI_DEVICE_CS_CNT_MAX; idx++) { + if (enable && idx < spi->num_chipselect) + spi->controller->last_cs[idx] = spi_get_chipselect(spi, 0); + else + spi->controller->last_cs[idx] = SPI_INVALID_CS; + } + + spi->controller->last_cs_mode_high = spi->mode & SPI_CS_HIGH; + if (spi->controller->last_cs_mode_high) enable = !enable; - if (gpio_is_valid(spi->cs_gpio)) { - /* Honour the SPI_NO_CS flag */ - if (!(spi->mode & SPI_NO_CS)) - gpio_set_value(spi->cs_gpio, !enable); - /* Some SPI masters need both GPIO CS & slave_select */ - if ((spi->controller->flags & SPI_MASTER_GPIO_SS) && + /* + * Handle chip select delays for GPIO based CS or controllers without + * programmable chip select timing. + */ + if ((spi_is_csgpiod(spi) || !spi->controller->set_cs_timing) && !activate) + spi_delay_exec(&spi->cs_hold, NULL); + + if (spi_is_csgpiod(spi)) { + if (!(spi->mode & SPI_NO_CS)) { + spi_for_each_valid_cs(spi, idx) { + if (spi_get_csgpiod(spi, idx)) + spi_toggle_csgpiod(spi, idx, enable, activate); + } + } + /* Some SPI controllers need both GPIO CS & ->set_cs() */ + if ((spi->controller->flags & SPI_CONTROLLER_GPIO_SS) && spi->controller->set_cs) spi->controller->set_cs(spi, !enable); } else if (spi->controller->set_cs) { spi->controller->set_cs(spi, !enable); } + + if (spi_is_csgpiod(spi) || !spi->controller->set_cs_timing) { + if (activate) + spi_delay_exec(&spi->cs_setup, NULL); + else + spi_delay_exec(&spi->cs_inactive, NULL); + } } #ifdef CONFIG_HAS_DMA -int spi_map_buf(struct spi_controller *ctlr, struct device *dev, - struct sg_table *sgt, void *buf, size_t len, - enum dma_data_direction dir) +static int spi_map_buf_attrs(struct spi_controller *ctlr, struct device *dev, + struct sg_table *sgt, void *buf, size_t len, + enum dma_data_direction dir, unsigned long attrs) { const bool vmalloced_buf = is_vmalloc_addr(buf); unsigned int max_seg_size = dma_get_max_seg_size(dev); @@ -808,10 +1140,10 @@ int spi_map_buf(struct spi_controller *ctlr, struct device *dev, int i, ret; if (vmalloced_buf || kmap_buf) { - desc_len = min_t(int, max_seg_size, PAGE_SIZE); + desc_len = min_t(unsigned long, max_seg_size, PAGE_SIZE); sgs = DIV_ROUND_UP(len + offset_in_page(buf), desc_len); } else if (virt_addr_valid(buf)) { - desc_len = min_t(int, max_seg_size, ctlr->max_dma_len); + desc_len = min_t(size_t, max_seg_size, ctlr->max_dma_len); sgs = DIV_ROUND_UP(len, desc_len); } else { return -EINVAL; @@ -854,26 +1186,37 @@ int spi_map_buf(struct spi_controller *ctlr, struct device *dev, sg = sg_next(sg); } - ret = dma_map_sg(dev, sgt->sgl, sgt->nents, dir); - if (!ret) - ret = -ENOMEM; + ret = dma_map_sgtable(dev, sgt, dir, attrs); if (ret < 0) { sg_free_table(sgt); return ret; } - sgt->nents = ret; - return 0; } +int spi_map_buf(struct spi_controller *ctlr, struct device *dev, + struct sg_table *sgt, void *buf, size_t len, + enum dma_data_direction dir) +{ + return spi_map_buf_attrs(ctlr, dev, sgt, buf, len, dir, 0); +} + +static void spi_unmap_buf_attrs(struct spi_controller *ctlr, + struct device *dev, struct sg_table *sgt, + enum dma_data_direction dir, + unsigned long attrs) +{ + dma_unmap_sgtable(dev, sgt, dir, attrs); + sg_free_table(sgt); + sgt->orig_nents = 0; + sgt->nents = 0; +} + void spi_unmap_buf(struct spi_controller *ctlr, struct device *dev, struct sg_table *sgt, enum dma_data_direction dir) { - if (sgt->orig_nents) { - dma_unmap_sg(dev, sgt->sgl, sgt->orig_nents, dir); - sg_free_table(sgt); - } + spi_unmap_buf_attrs(ctlr, dev, sgt, dir, 0); } static int __spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg) @@ -887,70 +1230,108 @@ static int __spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg) if (ctlr->dma_tx) tx_dev = ctlr->dma_tx->device->dev; + else if (ctlr->dma_map_dev) + tx_dev = ctlr->dma_map_dev; else tx_dev = ctlr->dev.parent; if (ctlr->dma_rx) rx_dev = ctlr->dma_rx->device->dev; + else if (ctlr->dma_map_dev) + rx_dev = ctlr->dma_map_dev; else rx_dev = ctlr->dev.parent; + ret = -ENOMSG; list_for_each_entry(xfer, &msg->transfers, transfer_list) { + /* The sync is done before each transfer. */ + unsigned long attrs = DMA_ATTR_SKIP_CPU_SYNC; + if (!ctlr->can_dma(ctlr, msg->spi, xfer)) continue; if (xfer->tx_buf != NULL) { - ret = spi_map_buf(ctlr, tx_dev, &xfer->tx_sg, - (void *)xfer->tx_buf, xfer->len, - DMA_TO_DEVICE); + ret = spi_map_buf_attrs(ctlr, tx_dev, &xfer->tx_sg, + (void *)xfer->tx_buf, + xfer->len, DMA_TO_DEVICE, + attrs); if (ret != 0) return ret; + + xfer->tx_sg_mapped = true; } if (xfer->rx_buf != NULL) { - ret = spi_map_buf(ctlr, rx_dev, &xfer->rx_sg, - xfer->rx_buf, xfer->len, - DMA_FROM_DEVICE); + ret = spi_map_buf_attrs(ctlr, rx_dev, &xfer->rx_sg, + xfer->rx_buf, xfer->len, + DMA_FROM_DEVICE, attrs); if (ret != 0) { - spi_unmap_buf(ctlr, tx_dev, &xfer->tx_sg, - DMA_TO_DEVICE); + spi_unmap_buf_attrs(ctlr, tx_dev, + &xfer->tx_sg, DMA_TO_DEVICE, + attrs); + return ret; } + + xfer->rx_sg_mapped = true; } } + /* No transfer has been mapped, bail out with success */ + if (ret) + return 0; - ctlr->cur_msg_mapped = true; + ctlr->cur_rx_dma_dev = rx_dev; + ctlr->cur_tx_dma_dev = tx_dev; return 0; } static int __spi_unmap_msg(struct spi_controller *ctlr, struct spi_message *msg) { + struct device *rx_dev = ctlr->cur_rx_dma_dev; + struct device *tx_dev = ctlr->cur_tx_dma_dev; struct spi_transfer *xfer; - struct device *tx_dev, *rx_dev; - if (!ctlr->cur_msg_mapped || !ctlr->can_dma) - return 0; + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + /* The sync has already been done after each transfer. */ + unsigned long attrs = DMA_ATTR_SKIP_CPU_SYNC; + + if (xfer->rx_sg_mapped) + spi_unmap_buf_attrs(ctlr, rx_dev, &xfer->rx_sg, + DMA_FROM_DEVICE, attrs); + xfer->rx_sg_mapped = false; + + if (xfer->tx_sg_mapped) + spi_unmap_buf_attrs(ctlr, tx_dev, &xfer->tx_sg, + DMA_TO_DEVICE, attrs); + xfer->tx_sg_mapped = false; + } - if (ctlr->dma_tx) - tx_dev = ctlr->dma_tx->device->dev; - else - tx_dev = ctlr->dev.parent; + return 0; +} - if (ctlr->dma_rx) - rx_dev = ctlr->dma_rx->device->dev; - else - rx_dev = ctlr->dev.parent; +static void spi_dma_sync_for_device(struct spi_controller *ctlr, + struct spi_transfer *xfer) +{ + struct device *rx_dev = ctlr->cur_rx_dma_dev; + struct device *tx_dev = ctlr->cur_tx_dma_dev; - list_for_each_entry(xfer, &msg->transfers, transfer_list) { - if (!ctlr->can_dma(ctlr, msg->spi, xfer)) - continue; + if (xfer->tx_sg_mapped) + dma_sync_sgtable_for_device(tx_dev, &xfer->tx_sg, DMA_TO_DEVICE); + if (xfer->rx_sg_mapped) + dma_sync_sgtable_for_device(rx_dev, &xfer->rx_sg, DMA_FROM_DEVICE); +} - spi_unmap_buf(ctlr, rx_dev, &xfer->rx_sg, DMA_FROM_DEVICE); - spi_unmap_buf(ctlr, tx_dev, &xfer->tx_sg, DMA_TO_DEVICE); - } +static void spi_dma_sync_for_cpu(struct spi_controller *ctlr, + struct spi_transfer *xfer) +{ + struct device *rx_dev = ctlr->cur_rx_dma_dev; + struct device *tx_dev = ctlr->cur_tx_dma_dev; - return 0; + if (xfer->rx_sg_mapped) + dma_sync_sgtable_for_cpu(rx_dev, &xfer->rx_sg, DMA_FROM_DEVICE); + if (xfer->tx_sg_mapped) + dma_sync_sgtable_for_cpu(tx_dev, &xfer->tx_sg, DMA_TO_DEVICE); } #else /* !CONFIG_HAS_DMA */ static inline int __spi_map_msg(struct spi_controller *ctlr, @@ -964,6 +1345,16 @@ static inline int __spi_unmap_msg(struct spi_controller *ctlr, { return 0; } + +static void spi_dma_sync_for_device(struct spi_controller *ctrl, + struct spi_transfer *xfer) +{ +} + +static void spi_dma_sync_for_cpu(struct spi_controller *ctrl, + struct spi_transfer *xfer) +{ +} #endif /* !CONFIG_HAS_DMA */ static inline int spi_unmap_msg(struct spi_controller *ctlr, @@ -991,7 +1382,8 @@ static int spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg) void *tmp; unsigned int max_tx, max_rx; - if (ctlr->flags & (SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX)) { + if ((ctlr->flags & (SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX)) + && !(msg->spi->mode & SPI_3WIRE)) { max_tx = 0; max_rx = 0; @@ -1006,11 +1398,10 @@ static int spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg) if (max_tx) { tmp = krealloc(ctlr->dummy_tx, max_tx, - GFP_KERNEL | GFP_DMA); + GFP_KERNEL | GFP_DMA | __GFP_ZERO); if (!tmp) return -ENOMEM; ctlr->dummy_tx = tmp; - memset(tmp, 0, max_tx); } if (max_rx) { @@ -1024,6 +1415,8 @@ static int spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg) if (max_tx || max_rx) { list_for_each_entry(xfer, &msg->transfers, transfer_list) { + if (!xfer->len) + continue; if (!xfer->tx_buf) xfer->tx_buf = ctlr->dummy_tx; if (!xfer->rx_buf) @@ -1039,20 +1432,34 @@ static int spi_transfer_wait(struct spi_controller *ctlr, struct spi_message *msg, struct spi_transfer *xfer) { - struct spi_statistics *statm = &ctlr->statistics; - struct spi_statistics *stats = &msg->spi->statistics; - unsigned long long ms = 1; + struct spi_statistics __percpu *statm = ctlr->pcpu_statistics; + struct spi_statistics __percpu *stats = msg->spi->pcpu_statistics; + u32 speed_hz = xfer->speed_hz; + unsigned long long ms; - if (spi_controller_is_slave(ctlr)) { + if (spi_controller_is_target(ctlr)) { if (wait_for_completion_interruptible(&ctlr->xfer_completion)) { dev_dbg(&msg->spi->dev, "SPI transfer interrupted\n"); return -EINTR; } } else { - ms = 8LL * 1000LL * xfer->len; - do_div(ms, xfer->speed_hz); - ms += ms + 200; /* some tolerance */ + if (!speed_hz) + speed_hz = 100000; + /* + * For each byte we wait for 8 cycles of the SPI clock. + * Since speed is defined in Hz and we want milliseconds, + * use respective multiplier, but before the division, + * otherwise we may get 0 for short transfers. + */ + ms = 8LL * MSEC_PER_SEC * xfer->len; + do_div(ms, speed_hz); + + /* + * Increase it twice and add 200 ms tolerance, use + * predefined maximum in case of overflow. + */ + ms += ms + 200; if (ms > UINT_MAX) ms = UINT_MAX; @@ -1066,10 +1473,115 @@ static int spi_transfer_wait(struct spi_controller *ctlr, "SPI transfer timed out\n"); return -ETIMEDOUT; } + + if (xfer->error & SPI_TRANS_FAIL_IO) + return -EIO; + } + + return 0; +} + +static void _spi_transfer_delay_ns(u32 ns) +{ + if (!ns) + return; + if (ns <= NSEC_PER_USEC) { + ndelay(ns); + } else { + u32 us = DIV_ROUND_UP(ns, NSEC_PER_USEC); + + fsleep(us); } +} + +int spi_delay_to_ns(struct spi_delay *_delay, struct spi_transfer *xfer) +{ + u32 delay = _delay->value; + u32 unit = _delay->unit; + u32 hz; + + if (!delay) + return 0; + + switch (unit) { + case SPI_DELAY_UNIT_USECS: + delay *= NSEC_PER_USEC; + break; + case SPI_DELAY_UNIT_NSECS: + /* Nothing to do here */ + break; + case SPI_DELAY_UNIT_SCK: + /* Clock cycles need to be obtained from spi_transfer */ + if (!xfer) + return -EINVAL; + /* + * If there is unknown effective speed, approximate it + * by underestimating with half of the requested Hz. + */ + hz = xfer->effective_speed_hz ?: xfer->speed_hz / 2; + if (!hz) + return -EINVAL; + + /* Convert delay to nanoseconds */ + delay *= DIV_ROUND_UP(NSEC_PER_SEC, hz); + break; + default: + return -EINVAL; + } + + return delay; +} +EXPORT_SYMBOL_GPL(spi_delay_to_ns); + +int spi_delay_exec(struct spi_delay *_delay, struct spi_transfer *xfer) +{ + int delay; + + might_sleep(); + + if (!_delay) + return -EINVAL; + + delay = spi_delay_to_ns(_delay, xfer); + if (delay < 0) + return delay; + + _spi_transfer_delay_ns(delay); return 0; } +EXPORT_SYMBOL_GPL(spi_delay_exec); + +static void _spi_transfer_cs_change_delay(struct spi_message *msg, + struct spi_transfer *xfer) +{ + u32 default_delay_ns = 10 * NSEC_PER_USEC; + u32 delay = xfer->cs_change_delay.value; + u32 unit = xfer->cs_change_delay.unit; + int ret; + + /* Return early on "fast" mode - for everything but USECS */ + if (!delay) { + if (unit == SPI_DELAY_UNIT_USECS) + _spi_transfer_delay_ns(default_delay_ns); + return; + } + + ret = spi_delay_exec(&xfer->cs_change_delay, xfer); + if (ret) { + dev_err_once(&msg->spi->dev, + "Use of unsupported delay unit %i, using default of %luus\n", + unit, default_delay_ns / NSEC_PER_USEC); + _spi_transfer_delay_ns(default_delay_ns); + } +} + +void spi_transfer_cs_change_delay_exec(struct spi_message *msg, + struct spi_transfer *xfer) +{ + _spi_transfer_cs_change_delay(msg, xfer); +} +EXPORT_SYMBOL_GPL(spi_transfer_cs_change_delay_exec); /* * spi_transfer_one_message - Default implementation of transfer_one_message() @@ -1084,10 +1596,11 @@ static int spi_transfer_one_message(struct spi_controller *ctlr, struct spi_transfer *xfer; bool keep_cs = false; int ret = 0; - struct spi_statistics *statm = &ctlr->statistics; - struct spi_statistics *stats = &msg->spi->statistics; + struct spi_statistics __percpu *statm = ctlr->pcpu_statistics; + struct spi_statistics __percpu *stats = msg->spi->pcpu_statistics; - spi_set_cs(msg->spi, true); + xfer = list_first_entry(&msg->transfers, struct spi_transfer, transfer_list); + spi_set_cs(msg->spi, !xfer->cs_off, false); SPI_STATISTICS_INCREMENT_FIELD(statm, messages); SPI_STATISTICS_INCREMENT_FIELD(stats, messages); @@ -1095,14 +1608,31 @@ static int spi_transfer_one_message(struct spi_controller *ctlr, list_for_each_entry(xfer, &msg->transfers, transfer_list) { trace_spi_transfer_start(msg, xfer); - spi_statistics_add_transfer_stats(statm, xfer, ctlr); - spi_statistics_add_transfer_stats(stats, xfer, ctlr); + spi_statistics_add_transfer_stats(statm, xfer, msg); + spi_statistics_add_transfer_stats(stats, xfer, msg); - if (xfer->tx_buf || xfer->rx_buf) { + if (!ctlr->ptp_sts_supported) { + xfer->ptp_sts_word_pre = 0; + ptp_read_system_prets(xfer->ptp_sts); + } + + if ((xfer->tx_buf || xfer->rx_buf) && xfer->len) { reinit_completion(&ctlr->xfer_completion); +fallback_pio: + spi_dma_sync_for_device(ctlr, xfer); ret = ctlr->transfer_one(ctlr, msg->spi, xfer); if (ret < 0) { + spi_dma_sync_for_cpu(ctlr, xfer); + + if ((xfer->tx_sg_mapped || xfer->rx_sg_mapped) && + (xfer->error & SPI_TRANS_FAIL_NO_START)) { + __spi_unmap_msg(ctlr, msg); + ctlr->fallback = true; + xfer->error &= ~SPI_TRANS_FAIL_NO_START; + goto fallback_pio; + } + SPI_STATISTICS_INCREMENT_FIELD(statm, errors); SPI_STATISTICS_INCREMENT_FIELD(stats, @@ -1117,6 +1647,8 @@ static int spi_transfer_one_message(struct spi_controller *ctlr, if (ret < 0) msg->status = ret; } + + spi_dma_sync_for_cpu(ctlr, xfer); } else { if (xfer->len) dev_err(&msg->spi->dev, @@ -1124,29 +1656,32 @@ static int spi_transfer_one_message(struct spi_controller *ctlr, xfer->len); } + if (!ctlr->ptp_sts_supported) { + ptp_read_system_postts(xfer->ptp_sts); + xfer->ptp_sts_word_post = xfer->len; + } + trace_spi_transfer_stop(msg, xfer); if (msg->status != -EINPROGRESS) goto out; - if (xfer->delay_usecs) { - u16 us = xfer->delay_usecs; - - if (us <= 10) - udelay(us); - else - usleep_range(us, us + DIV_ROUND_UP(us, 10)); - } + spi_transfer_delay_exec(xfer); if (xfer->cs_change) { if (list_is_last(&xfer->transfer_list, &msg->transfers)) { keep_cs = true; } else { - spi_set_cs(msg->spi, false); - udelay(10); - spi_set_cs(msg->spi, true); + if (!xfer->cs_off) + spi_set_cs(msg->spi, false, false); + _spi_transfer_cs_change_delay(msg, xfer); + if (!list_next_entry(xfer, transfer_list)->cs_off) + spi_set_cs(msg->spi, true, false); } + } else if (!list_is_last(&xfer->transfer_list, &msg->transfers) && + xfer->cs_off != list_next_entry(xfer, transfer_list)->cs_off) { + spi_set_cs(msg->spi, xfer->cs_off, false); } msg->actual_length += xfer->len; @@ -1154,7 +1689,7 @@ static int spi_transfer_one_message(struct spi_controller *ctlr, out: if (ret != 0 || !keep_cs) - spi_set_cs(msg->spi, false); + spi_set_cs(msg->spi, false, false); if (msg->status == -EINPROGRESS) msg->status = ret; @@ -1162,8 +1697,6 @@ out: if (msg->status && ctlr->handle_err) ctlr->handle_err(ctlr, msg); - spi_res_release(ctlr, msg); - spi_finalize_current_message(ctlr); return ret; @@ -1183,12 +1716,120 @@ void spi_finalize_current_transfer(struct spi_controller *ctlr) } EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); +static void spi_idle_runtime_pm(struct spi_controller *ctlr) +{ + if (ctlr->auto_runtime_pm) { + pm_runtime_put_autosuspend(ctlr->dev.parent); + } +} + +static int __spi_pump_transfer_message(struct spi_controller *ctlr, + struct spi_message *msg, bool was_busy) +{ + struct spi_transfer *xfer; + int ret; + + if (!was_busy && ctlr->auto_runtime_pm) { + ret = pm_runtime_get_sync(ctlr->dev.parent); + if (ret < 0) { + pm_runtime_put_noidle(ctlr->dev.parent); + dev_err(&ctlr->dev, "Failed to power device: %d\n", + ret); + + msg->status = ret; + spi_finalize_current_message(ctlr); + + return ret; + } + } + + if (!was_busy) + trace_spi_controller_busy(ctlr); + + if (!was_busy && ctlr->prepare_transfer_hardware) { + ret = ctlr->prepare_transfer_hardware(ctlr); + if (ret) { + dev_err(&ctlr->dev, + "failed to prepare transfer hardware: %d\n", + ret); + + if (ctlr->auto_runtime_pm) + pm_runtime_put(ctlr->dev.parent); + + msg->status = ret; + spi_finalize_current_message(ctlr); + + return ret; + } + } + + trace_spi_message_start(msg); + + if (ctlr->prepare_message) { + ret = ctlr->prepare_message(ctlr, msg); + if (ret) { + dev_err(&ctlr->dev, "failed to prepare message: %d\n", + ret); + msg->status = ret; + spi_finalize_current_message(ctlr); + return ret; + } + msg->prepared = true; + } + + ret = spi_map_msg(ctlr, msg); + if (ret) { + msg->status = ret; + spi_finalize_current_message(ctlr); + return ret; + } + + if (!ctlr->ptp_sts_supported && !ctlr->transfer_one) { + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + xfer->ptp_sts_word_pre = 0; + ptp_read_system_prets(xfer->ptp_sts); + } + } + + /* + * Drivers implementation of transfer_one_message() must arrange for + * spi_finalize_current_message() to get called. Most drivers will do + * this in the calling context, but some don't. For those cases, a + * completion is used to guarantee that this function does not return + * until spi_finalize_current_message() is done accessing + * ctlr->cur_msg. + * Use of the following two flags enable to opportunistically skip the + * use of the completion since its use involves expensive spin locks. + * In case of a race with the context that calls + * spi_finalize_current_message() the completion will always be used, + * due to strict ordering of these flags using barriers. + */ + WRITE_ONCE(ctlr->cur_msg_incomplete, true); + WRITE_ONCE(ctlr->cur_msg_need_completion, false); + reinit_completion(&ctlr->cur_msg_completion); + smp_wmb(); /* Make these available to spi_finalize_current_message() */ + + ret = ctlr->transfer_one_message(ctlr, msg); + if (ret) { + dev_err(&ctlr->dev, + "failed to transfer one message from queue\n"); + return ret; + } + + WRITE_ONCE(ctlr->cur_msg_need_completion, true); + smp_mb(); /* See spi_finalize_current_message()... */ + if (READ_ONCE(ctlr->cur_msg_incomplete)) + wait_for_completion(&ctlr->cur_msg_completion); + + return 0; +} + /** - * __spi_pump_messages - function which processes spi message queue + * __spi_pump_messages - function which processes SPI message queue * @ctlr: controller to process queue for * @in_kthread: true if we are in the context of the message pump thread * - * This function checks if there is any spi message in the queue that + * This function checks if there is any SPI message in the queue that * needs processing and if so call out to the driver to initialize hardware * and transfer each message. * @@ -1198,43 +1839,42 @@ EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); */ static void __spi_pump_messages(struct spi_controller *ctlr, bool in_kthread) { - unsigned long flags; + struct spi_message *msg; bool was_busy = false; + unsigned long flags; int ret; + /* Take the I/O mutex */ + mutex_lock(&ctlr->io_mutex); + /* Lock queue */ spin_lock_irqsave(&ctlr->queue_lock, flags); /* Make sure we are not already running a message */ - if (ctlr->cur_msg) { - spin_unlock_irqrestore(&ctlr->queue_lock, flags); - return; - } - - /* If another context is idling the device then defer */ - if (ctlr->idling) { - kthread_queue_work(&ctlr->kworker, &ctlr->pump_messages); - spin_unlock_irqrestore(&ctlr->queue_lock, flags); - return; - } + if (ctlr->cur_msg) + goto out_unlock; /* Check if the queue is idle */ if (list_empty(&ctlr->queue) || !ctlr->running) { - if (!ctlr->busy) { - spin_unlock_irqrestore(&ctlr->queue_lock, flags); - return; - } + if (!ctlr->busy) + goto out_unlock; - /* Only do teardown in the thread */ + /* Defer any non-atomic teardown to the thread */ if (!in_kthread) { - kthread_queue_work(&ctlr->kworker, - &ctlr->pump_messages); - spin_unlock_irqrestore(&ctlr->queue_lock, flags); - return; + if (!ctlr->dummy_rx && !ctlr->dummy_tx && + !ctlr->unprepare_transfer_hardware) { + spi_idle_runtime_pm(ctlr); + ctlr->busy = false; + ctlr->queue_empty = true; + trace_spi_controller_idle(ctlr); + } else { + kthread_queue_work(ctlr->kworker, + &ctlr->pump_messages); + } + goto out_unlock; } ctlr->busy = false; - ctlr->idling = true; spin_unlock_irqrestore(&ctlr->queue_lock, flags); kfree(ctlr->dummy_rx); @@ -1245,92 +1885,41 @@ static void __spi_pump_messages(struct spi_controller *ctlr, bool in_kthread) ctlr->unprepare_transfer_hardware(ctlr)) dev_err(&ctlr->dev, "failed to unprepare transfer hardware\n"); - if (ctlr->auto_runtime_pm) { - pm_runtime_mark_last_busy(ctlr->dev.parent); - pm_runtime_put_autosuspend(ctlr->dev.parent); - } + spi_idle_runtime_pm(ctlr); trace_spi_controller_idle(ctlr); spin_lock_irqsave(&ctlr->queue_lock, flags); - ctlr->idling = false; - spin_unlock_irqrestore(&ctlr->queue_lock, flags); - return; + ctlr->queue_empty = true; + goto out_unlock; } /* Extract head of queue */ - ctlr->cur_msg = - list_first_entry(&ctlr->queue, struct spi_message, queue); + msg = list_first_entry(&ctlr->queue, struct spi_message, queue); + ctlr->cur_msg = msg; - list_del_init(&ctlr->cur_msg->queue); + list_del_init(&msg->queue); if (ctlr->busy) was_busy = true; else ctlr->busy = true; spin_unlock_irqrestore(&ctlr->queue_lock, flags); - mutex_lock(&ctlr->io_mutex); + ret = __spi_pump_transfer_message(ctlr, msg, was_busy); + kthread_queue_work(ctlr->kworker, &ctlr->pump_messages); - if (!was_busy && ctlr->auto_runtime_pm) { - ret = pm_runtime_get_sync(ctlr->dev.parent); - if (ret < 0) { - pm_runtime_put_noidle(ctlr->dev.parent); - dev_err(&ctlr->dev, "Failed to power device: %d\n", - ret); - mutex_unlock(&ctlr->io_mutex); - return; - } - } - - if (!was_busy) - trace_spi_controller_busy(ctlr); - - if (!was_busy && ctlr->prepare_transfer_hardware) { - ret = ctlr->prepare_transfer_hardware(ctlr); - if (ret) { - dev_err(&ctlr->dev, - "failed to prepare transfer hardware\n"); - - if (ctlr->auto_runtime_pm) - pm_runtime_put(ctlr->dev.parent); - mutex_unlock(&ctlr->io_mutex); - return; - } - } - - trace_spi_message_start(ctlr->cur_msg); - - if (ctlr->prepare_message) { - ret = ctlr->prepare_message(ctlr, ctlr->cur_msg); - if (ret) { - dev_err(&ctlr->dev, "failed to prepare message: %d\n", - ret); - ctlr->cur_msg->status = ret; - spi_finalize_current_message(ctlr); - goto out; - } - ctlr->cur_msg_prepared = true; - } - - ret = spi_map_msg(ctlr, ctlr->cur_msg); - if (ret) { - ctlr->cur_msg->status = ret; - spi_finalize_current_message(ctlr); - goto out; - } - - ret = ctlr->transfer_one_message(ctlr, ctlr->cur_msg); - if (ret) { - dev_err(&ctlr->dev, - "failed to transfer one message from queue\n"); - goto out; - } + ctlr->cur_msg = NULL; + ctlr->fallback = false; -out: mutex_unlock(&ctlr->io_mutex); /* Prod the scheduler in case transfer_one() was busy waiting */ if (!ret) cond_resched(); + return; + +out_unlock: + spin_unlock_irqrestore(&ctlr->queue_lock, flags); + mutex_unlock(&ctlr->io_mutex); } /** @@ -1345,20 +1934,124 @@ static void spi_pump_messages(struct kthread_work *work) __spi_pump_messages(ctlr, true); } -static int spi_init_queue(struct spi_controller *ctlr) +/** + * spi_take_timestamp_pre - helper to collect the beginning of the TX timestamp + * @ctlr: Pointer to the spi_controller structure of the driver + * @xfer: Pointer to the transfer being timestamped + * @progress: How many words (not bytes) have been transferred so far + * @irqs_off: If true, will disable IRQs and preemption for the duration of the + * transfer, for less jitter in time measurement. Only compatible + * with PIO drivers. If true, must follow up with + * spi_take_timestamp_post or otherwise system will crash. + * WARNING: for fully predictable results, the CPU frequency must + * also be under control (governor). + * + * This is a helper for drivers to collect the beginning of the TX timestamp + * for the requested byte from the SPI transfer. The frequency with which this + * function must be called (once per word, once for the whole transfer, once + * per batch of words etc) is arbitrary as long as the @tx buffer offset is + * greater than or equal to the requested byte at the time of the call. The + * timestamp is only taken once, at the first such call. It is assumed that + * the driver advances its @tx buffer pointer monotonically. + */ +void spi_take_timestamp_pre(struct spi_controller *ctlr, + struct spi_transfer *xfer, + size_t progress, bool irqs_off) +{ + if (!xfer->ptp_sts) + return; + + if (xfer->timestamped) + return; + + if (progress > xfer->ptp_sts_word_pre) + return; + + /* Capture the resolution of the timestamp */ + xfer->ptp_sts_word_pre = progress; + + if (irqs_off) { + local_irq_save(ctlr->irq_flags); + preempt_disable(); + } + + ptp_read_system_prets(xfer->ptp_sts); +} +EXPORT_SYMBOL_GPL(spi_take_timestamp_pre); + +/** + * spi_take_timestamp_post - helper to collect the end of the TX timestamp + * @ctlr: Pointer to the spi_controller structure of the driver + * @xfer: Pointer to the transfer being timestamped + * @progress: How many words (not bytes) have been transferred so far + * @irqs_off: If true, will re-enable IRQs and preemption for the local CPU. + * + * This is a helper for drivers to collect the end of the TX timestamp for + * the requested byte from the SPI transfer. Can be called with an arbitrary + * frequency: only the first call where @tx exceeds or is equal to the + * requested word will be timestamped. + */ +void spi_take_timestamp_post(struct spi_controller *ctlr, + struct spi_transfer *xfer, + size_t progress, bool irqs_off) { - struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; + if (!xfer->ptp_sts) + return; + + if (xfer->timestamped) + return; + + if (progress < xfer->ptp_sts_word_post) + return; + + ptp_read_system_postts(xfer->ptp_sts); + + if (irqs_off) { + local_irq_restore(ctlr->irq_flags); + preempt_enable(); + } + + /* Capture the resolution of the timestamp */ + xfer->ptp_sts_word_post = progress; + xfer->timestamped = 1; +} +EXPORT_SYMBOL_GPL(spi_take_timestamp_post); + +/** + * spi_set_thread_rt - set the controller to pump at realtime priority + * @ctlr: controller to boost priority of + * + * This can be called because the controller requested realtime priority + * (by setting the ->rt value before calling spi_register_controller()) or + * because a device on the bus said that its transfers needed realtime + * priority. + * + * NOTE: at the moment if any device on a bus says it needs realtime then + * the thread will be at realtime priority for all transfers on that + * controller. If this eventually becomes a problem we may see if we can + * find a way to boost the priority only temporarily during relevant + * transfers. + */ +static void spi_set_thread_rt(struct spi_controller *ctlr) +{ + dev_info(&ctlr->dev, + "will run message pump with realtime priority\n"); + sched_set_fifo(ctlr->kworker->task); +} + +static int spi_init_queue(struct spi_controller *ctlr) +{ ctlr->running = false; ctlr->busy = false; + ctlr->queue_empty = true; - kthread_init_worker(&ctlr->kworker); - ctlr->kworker_task = kthread_run(kthread_worker_fn, &ctlr->kworker, - "%s", dev_name(&ctlr->dev)); - if (IS_ERR(ctlr->kworker_task)) { - dev_err(&ctlr->dev, "failed to create message pump task\n"); - return PTR_ERR(ctlr->kworker_task); + ctlr->kworker = kthread_run_worker(0, dev_name(&ctlr->dev)); + if (IS_ERR(ctlr->kworker)) { + dev_err(&ctlr->dev, "failed to create message pump kworker\n"); + return PTR_ERR(ctlr->kworker); } + kthread_init_work(&ctlr->pump_messages, spi_pump_messages); /* @@ -1368,11 +2061,8 @@ static int spi_init_queue(struct spi_controller *ctlr) * request and the scheduling of the message pump thread. Without this * setting the message pump thread will remain at default priority. */ - if (ctlr->rt) { - dev_info(&ctlr->dev, - "will run message pump with realtime priority\n"); - sched_setscheduler(ctlr->kworker_task, SCHED_FIFO, ¶m); - } + if (ctlr->rt) + spi_set_thread_rt(ctlr); return 0; } @@ -1392,7 +2082,7 @@ struct spi_message *spi_get_next_queued_message(struct spi_controller *ctlr) struct spi_message *next; unsigned long flags; - /* get a pointer to the next message, if any */ + /* Get a pointer to the next message, if any */ spin_lock_irqsave(&ctlr->queue_lock, flags); next = list_first_entry_or_null(&ctlr->queue, struct spi_message, queue); @@ -1402,6 +2092,44 @@ struct spi_message *spi_get_next_queued_message(struct spi_controller *ctlr) } EXPORT_SYMBOL_GPL(spi_get_next_queued_message); +/* + * __spi_unoptimize_message - shared implementation of spi_unoptimize_message() + * and spi_maybe_unoptimize_message() + * @msg: the message to unoptimize + * + * Peripheral drivers should use spi_unoptimize_message() and callers inside + * core should use spi_maybe_unoptimize_message() rather than calling this + * function directly. + * + * It is not valid to call this on a message that is not currently optimized. + */ +static void __spi_unoptimize_message(struct spi_message *msg) +{ + struct spi_controller *ctlr = msg->spi->controller; + + if (ctlr->unoptimize_message) + ctlr->unoptimize_message(msg); + + spi_res_release(ctlr, msg); + + msg->optimized = false; + msg->opt_state = NULL; +} + +/* + * spi_maybe_unoptimize_message - unoptimize msg not managed by a peripheral + * @msg: the message to unoptimize + * + * This function is used to unoptimize a message if and only if it was + * optimized by the core (via spi_maybe_optimize_message()). + */ +static void spi_maybe_unoptimize_message(struct spi_message *msg) +{ + if (!msg->pre_optimized && msg->optimized && + !msg->spi->controller->defer_optimize_message) + __spi_unoptimize_message(msg); +} + /** * spi_finalize_current_message() - the current message is complete * @ctlr: the controller to return the message to @@ -1411,17 +2139,26 @@ EXPORT_SYMBOL_GPL(spi_get_next_queued_message); */ void spi_finalize_current_message(struct spi_controller *ctlr) { + struct spi_transfer *xfer; struct spi_message *mesg; - unsigned long flags; int ret; - spin_lock_irqsave(&ctlr->queue_lock, flags); mesg = ctlr->cur_msg; - spin_unlock_irqrestore(&ctlr->queue_lock, flags); + + if (!ctlr->ptp_sts_supported && !ctlr->transfer_one) { + list_for_each_entry(xfer, &mesg->transfers, transfer_list) { + ptp_read_system_postts(xfer->ptp_sts); + xfer->ptp_sts_word_post = xfer->len; + } + } + + if (unlikely(ctlr->ptp_sts_supported)) + list_for_each_entry(xfer, &mesg->transfers, transfer_list) + WARN_ON_ONCE(xfer->ptp_sts && !xfer->timestamped); spi_unmap_msg(ctlr, mesg); - if (ctlr->cur_msg_prepared && ctlr->unprepare_message) { + if (mesg->prepared && ctlr->unprepare_message) { ret = ctlr->unprepare_message(ctlr, mesg); if (ret) { dev_err(&ctlr->dev, "failed to unprepare message: %d\n", @@ -1429,11 +2166,14 @@ void spi_finalize_current_message(struct spi_controller *ctlr) } } - spin_lock_irqsave(&ctlr->queue_lock, flags); - ctlr->cur_msg = NULL; - ctlr->cur_msg_prepared = false; - kthread_queue_work(&ctlr->kworker, &ctlr->pump_messages); - spin_unlock_irqrestore(&ctlr->queue_lock, flags); + mesg->prepared = false; + + spi_maybe_unoptimize_message(mesg); + + WRITE_ONCE(ctlr->cur_msg_incomplete, false); + smp_mb(); /* See __spi_pump_transfer_message()... */ + if (READ_ONCE(ctlr->cur_msg_need_completion)) + complete(&ctlr->cur_msg_completion); trace_spi_message_done(mesg); @@ -1458,18 +2198,15 @@ static int spi_start_queue(struct spi_controller *ctlr) ctlr->cur_msg = NULL; spin_unlock_irqrestore(&ctlr->queue_lock, flags); - kthread_queue_work(&ctlr->kworker, &ctlr->pump_messages); + kthread_queue_work(ctlr->kworker, &ctlr->pump_messages); return 0; } static int spi_stop_queue(struct spi_controller *ctlr) { + unsigned int limit = 500; unsigned long flags; - unsigned limit = 500; - int ret = 0; - - spin_lock_irqsave(&ctlr->queue_lock, flags); /* * This is a bit lame, but is optimized for the common execution path. @@ -1477,24 +2214,18 @@ static int spi_stop_queue(struct spi_controller *ctlr) * execution path (pump_messages) would be required to call wake_up or * friends on every SPI message. Do this instead. */ - while ((!list_empty(&ctlr->queue) || ctlr->busy) && limit--) { + do { + spin_lock_irqsave(&ctlr->queue_lock, flags); + if (list_empty(&ctlr->queue) && !ctlr->busy) { + ctlr->running = false; + spin_unlock_irqrestore(&ctlr->queue_lock, flags); + return 0; + } spin_unlock_irqrestore(&ctlr->queue_lock, flags); usleep_range(10000, 11000); - spin_lock_irqsave(&ctlr->queue_lock, flags); - } - - if (!list_empty(&ctlr->queue) || ctlr->busy) - ret = -EBUSY; - else - ctlr->running = false; + } while (--limit); - spin_unlock_irqrestore(&ctlr->queue_lock, flags); - - if (ret) { - dev_warn(&ctlr->dev, "could not stop message queue\n"); - return ret; - } - return ret; + return -EBUSY; } static int spi_destroy_queue(struct spi_controller *ctlr) @@ -1514,8 +2245,7 @@ static int spi_destroy_queue(struct spi_controller *ctlr) return ret; } - kthread_flush_worker(&ctlr->kworker); - kthread_stop(ctlr->kworker_task); + kthread_destroy_worker(ctlr->kworker); return 0; } @@ -1537,8 +2267,9 @@ static int __spi_queued_transfer(struct spi_device *spi, msg->status = -EINPROGRESS; list_add_tail(&msg->queue, &ctlr->queue); + ctlr->queue_empty = false; if (!ctlr->busy && need_pump) - kthread_queue_work(&ctlr->kworker, &ctlr->pump_messages); + kthread_queue_work(ctlr->kworker, &ctlr->pump_messages); spin_unlock_irqrestore(&ctlr->queue_lock, flags); return 0; @@ -1546,8 +2277,8 @@ static int __spi_queued_transfer(struct spi_device *spi, /** * spi_queued_transfer - transfer function for queued transfers - * @spi: spi device which is requesting transfer - * @msg: spi message which is to handled is queued to driver queue + * @spi: SPI device which is requesting transfer + * @msg: SPI message which is to handled is queued to driver queue * * Return: zero on success, else a negative error code. */ @@ -1604,27 +2335,46 @@ void spi_flush_queue(struct spi_controller *ctlr) /*-------------------------------------------------------------------------*/ #if defined(CONFIG_OF) +static void of_spi_parse_dt_cs_delay(struct device_node *nc, + struct spi_delay *delay, const char *prop) +{ + u32 value; + + if (!of_property_read_u32(nc, prop, &value)) { + if (value > U16_MAX) { + delay->value = DIV_ROUND_UP(value, 1000); + delay->unit = SPI_DELAY_UNIT_USECS; + } else { + delay->value = value; + delay->unit = SPI_DELAY_UNIT_NSECS; + } + } +} + static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi, struct device_node *nc) { - u32 value; - int rc; + u32 value, cs[SPI_DEVICE_CS_CNT_MAX]; + int rc, idx; /* Mode (clock phase/polarity/etc.) */ if (of_property_read_bool(nc, "spi-cpha")) spi->mode |= SPI_CPHA; if (of_property_read_bool(nc, "spi-cpol")) spi->mode |= SPI_CPOL; - if (of_property_read_bool(nc, "spi-cs-high")) - spi->mode |= SPI_CS_HIGH; if (of_property_read_bool(nc, "spi-3wire")) spi->mode |= SPI_3WIRE; if (of_property_read_bool(nc, "spi-lsb-first")) spi->mode |= SPI_LSB_FIRST; + if (of_property_read_bool(nc, "spi-cs-high")) + spi->mode |= SPI_CS_HIGH; /* Device DUAL/QUAD mode */ if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) { switch (value) { + case 0: + spi->mode |= SPI_NO_TX; + break; case 1: break; case 2: @@ -1646,6 +2396,9 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi, if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) { switch (value) { + case 0: + spi->mode |= SPI_NO_RX; + break; case 1: break; case 2: @@ -1665,7 +2418,7 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi, } } - if (spi_controller_is_slave(ctlr)) { + if (spi_controller_is_target(ctlr)) { if (!of_node_name_eq(nc, "slave")) { dev_err(&ctlr->dev, "%pOF is not called 'slave'\n", nc); @@ -1675,22 +2428,38 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi, } /* Device address */ - rc = of_property_read_u32(nc, "reg", &value); - if (rc) { + rc = of_property_read_variable_u32_array(nc, "reg", &cs[0], 1, + SPI_DEVICE_CS_CNT_MAX); + if (rc < 0) { dev_err(&ctlr->dev, "%pOF has no valid 'reg' property (%d)\n", nc, rc); return rc; } - spi->chip_select = value; - /* Device speed */ - rc = of_property_read_u32(nc, "spi-max-frequency", &value); - if (rc) { - dev_err(&ctlr->dev, - "%pOF has no valid 'spi-max-frequency' property (%d)\n", nc, rc); - return rc; + if ((of_property_present(nc, "parallel-memories")) && + (!(ctlr->flags & SPI_CONTROLLER_MULTI_CS))) { + dev_err(&ctlr->dev, "SPI controller doesn't support multi CS\n"); + return -EINVAL; } - spi->max_speed_hz = value; + + spi->num_chipselect = rc; + for (idx = 0; idx < rc; idx++) + spi_set_chipselect(spi, idx, cs[idx]); + + /* + * By default spi->chip_select[0] will hold the physical CS number, + * so set bit 0 in spi->cs_index_mask. + */ + spi->cs_index_mask = BIT(0); + + /* Device speed */ + if (!of_property_read_u32(nc, "spi-max-frequency", &value)) + spi->max_speed_hz = value; + + /* Device CS delays */ + of_spi_parse_dt_cs_delay(nc, &spi->cs_setup, "spi-cs-setup-delay-ns"); + of_spi_parse_dt_cs_delay(nc, &spi->cs_hold, "spi-cs-hold-delay-ns"); + of_spi_parse_dt_cs_delay(nc, &spi->cs_inactive, "spi-cs-inactive-delay-ns"); return 0; } @@ -1710,8 +2479,8 @@ of_register_spi_device(struct spi_controller *ctlr, struct device_node *nc) } /* Select device driver */ - rc = of_modalias_node(nc, spi->modalias, - sizeof(spi->modalias)); + rc = of_alias_from_compatible(nc, spi->modalias, + sizeof(spi->modalias)); if (rc < 0) { dev_err(&ctlr->dev, "cannot find modalias for %pOF\n", nc); goto err_out; @@ -1723,7 +2492,8 @@ of_register_spi_device(struct spi_controller *ctlr, struct device_node *nc) /* Store a pointer to the node in the device structure */ of_node_get(nc); - spi->dev.of_node = nc; + + device_set_node(&spi->dev, of_fwnode_handle(nc)); /* Register the new device */ rc = spi_add_device(spi); @@ -1746,16 +2516,13 @@ err_out: * @ctlr: Pointer to spi_controller device * * Registers an spi_device for each child node of controller node which - * represents a valid SPI slave. + * represents a valid SPI target device. */ static void of_register_spi_devices(struct spi_controller *ctlr) { struct spi_device *spi; struct device_node *nc; - if (!ctlr->dev.of_node) - return; - for_each_available_child_of_node(ctlr->dev.of_node, nc) { if (of_node_test_and_set_flag(nc, OF_POPULATED)) continue; @@ -1771,10 +2538,118 @@ static void of_register_spi_devices(struct spi_controller *ctlr) static void of_register_spi_devices(struct spi_controller *ctlr) { } #endif +/** + * spi_new_ancillary_device() - Register ancillary SPI device + * @spi: Pointer to the main SPI device registering the ancillary device + * @chip_select: Chip Select of the ancillary device + * + * Register an ancillary SPI device; for example some chips have a chip-select + * for normal device usage and another one for setup/firmware upload. + * + * This may only be called from main SPI device's probe routine. + * + * Return: 0 on success; negative errno on failure + */ +struct spi_device *spi_new_ancillary_device(struct spi_device *spi, + u8 chip_select) +{ + struct spi_controller *ctlr = spi->controller; + struct spi_device *ancillary; + int rc; + + /* Alloc an spi_device */ + ancillary = spi_alloc_device(ctlr); + if (!ancillary) { + rc = -ENOMEM; + goto err_out; + } + + strscpy(ancillary->modalias, "dummy", sizeof(ancillary->modalias)); + + /* Use provided chip-select for ancillary device */ + spi_set_chipselect(ancillary, 0, chip_select); + + /* Take over SPI mode/speed from SPI main device */ + ancillary->max_speed_hz = spi->max_speed_hz; + ancillary->mode = spi->mode; + /* + * By default spi->chip_select[0] will hold the physical CS number, + * so set bit 0 in spi->cs_index_mask. + */ + ancillary->cs_index_mask = BIT(0); + + WARN_ON(!mutex_is_locked(&ctlr->add_lock)); + + /* Register the new device */ + rc = __spi_add_device(ancillary); + if (rc) { + dev_err(&spi->dev, "failed to register ancillary device\n"); + goto err_out; + } + + return ancillary; + +err_out: + spi_dev_put(ancillary); + return ERR_PTR(rc); +} +EXPORT_SYMBOL_GPL(spi_new_ancillary_device); + #ifdef CONFIG_ACPI -static void acpi_spi_parse_apple_properties(struct spi_device *spi) +struct acpi_spi_lookup { + struct spi_controller *ctlr; + u32 max_speed_hz; + u32 mode; + int irq; + u8 bits_per_word; + u8 chip_select; + int n; + int index; +}; + +static int acpi_spi_count(struct acpi_resource *ares, void *data) +{ + struct acpi_resource_spi_serialbus *sb; + int *count = data; + + if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) + return 1; + + sb = &ares->data.spi_serial_bus; + if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_SPI) + return 1; + + *count = *count + 1; + + return 1; +} + +/** + * acpi_spi_count_resources - Count the number of SpiSerialBus resources + * @adev: ACPI device + * + * Return: the number of SpiSerialBus resources in the ACPI-device's + * resource-list; or a negative error code. + */ +int acpi_spi_count_resources(struct acpi_device *adev) +{ + LIST_HEAD(r); + int count = 0; + int ret; + + ret = acpi_dev_get_resources(adev, &r, acpi_spi_count, &count); + if (ret < 0) + return ret; + + acpi_dev_free_resource_list(&r); + + return count; +} +EXPORT_SYMBOL_GPL(acpi_spi_count_resources); + +static void acpi_spi_parse_apple_properties(struct acpi_device *dev, + struct acpi_spi_lookup *lookup) { - struct acpi_device *dev = ACPI_COMPANION(&spi->dev); const union acpi_object *obj; if (!x86_apple_machine) @@ -1782,35 +2657,65 @@ static void acpi_spi_parse_apple_properties(struct spi_device *spi) if (!acpi_dev_get_property(dev, "spiSclkPeriod", ACPI_TYPE_BUFFER, &obj) && obj->buffer.length >= 4) - spi->max_speed_hz = NSEC_PER_SEC / *(u32 *)obj->buffer.pointer; + lookup->max_speed_hz = NSEC_PER_SEC / *(u32 *)obj->buffer.pointer; if (!acpi_dev_get_property(dev, "spiWordSize", ACPI_TYPE_BUFFER, &obj) && obj->buffer.length == 8) - spi->bits_per_word = *(u64 *)obj->buffer.pointer; + lookup->bits_per_word = *(u64 *)obj->buffer.pointer; if (!acpi_dev_get_property(dev, "spiBitOrder", ACPI_TYPE_BUFFER, &obj) && obj->buffer.length == 8 && !*(u64 *)obj->buffer.pointer) - spi->mode |= SPI_LSB_FIRST; + lookup->mode |= SPI_LSB_FIRST; if (!acpi_dev_get_property(dev, "spiSPO", ACPI_TYPE_BUFFER, &obj) && obj->buffer.length == 8 && *(u64 *)obj->buffer.pointer) - spi->mode |= SPI_CPOL; + lookup->mode |= SPI_CPOL; if (!acpi_dev_get_property(dev, "spiSPH", ACPI_TYPE_BUFFER, &obj) && obj->buffer.length == 8 && *(u64 *)obj->buffer.pointer) - spi->mode |= SPI_CPHA; + lookup->mode |= SPI_CPHA; } static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) { - struct spi_device *spi = data; - struct spi_controller *ctlr = spi->controller; + struct acpi_spi_lookup *lookup = data; + struct spi_controller *ctlr = lookup->ctlr; if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { struct acpi_resource_spi_serialbus *sb; + acpi_handle parent_handle; + acpi_status status; sb = &ares->data.spi_serial_bus; if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_SPI) { + + if (lookup->index != -1 && lookup->n++ != lookup->index) + return 1; + + status = acpi_get_handle(NULL, + sb->resource_source.string_ptr, + &parent_handle); + + if (ACPI_FAILURE(status)) + return -ENODEV; + + if (ctlr) { + if (!device_match_acpi_handle(ctlr->dev.parent, parent_handle)) + return -ENODEV; + } else { + struct acpi_device *adev; + + adev = acpi_fetch_acpi_dev(parent_handle); + if (!adev) + return -ENODEV; + + ctlr = acpi_spi_find_controller_by_adev(adev); + if (!ctlr) + return -EPROBE_DEFER; + + lookup->ctlr = ctlr; + } + /* * ACPI DeviceSelection numbering is handled by the * host controller driver in Windows and can vary @@ -1823,67 +2728,138 @@ static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) sb->device_selection); if (cs < 0) return cs; - spi->chip_select = cs; + lookup->chip_select = cs; } else { - spi->chip_select = sb->device_selection; + lookup->chip_select = sb->device_selection; } - spi->max_speed_hz = sb->connection_speed; + lookup->max_speed_hz = sb->connection_speed; + lookup->bits_per_word = sb->data_bit_length; if (sb->clock_phase == ACPI_SPI_SECOND_PHASE) - spi->mode |= SPI_CPHA; + lookup->mode |= SPI_CPHA; if (sb->clock_polarity == ACPI_SPI_START_HIGH) - spi->mode |= SPI_CPOL; + lookup->mode |= SPI_CPOL; if (sb->device_polarity == ACPI_SPI_ACTIVE_HIGH) - spi->mode |= SPI_CS_HIGH; + lookup->mode |= SPI_CS_HIGH; } - } else if (spi->irq < 0) { + } else if (lookup->irq < 0) { struct resource r; if (acpi_dev_resource_interrupt(ares, 0, &r)) - spi->irq = r.start; + lookup->irq = r.start; } /* Always tell the ACPI core to skip this resource */ return 1; } -static acpi_status acpi_register_spi_device(struct spi_controller *ctlr, - struct acpi_device *adev) +/** + * acpi_spi_device_alloc - Allocate a spi device, and fill it in with ACPI information + * @ctlr: controller to which the spi device belongs + * @adev: ACPI Device for the spi device + * @index: Index of the spi resource inside the ACPI Node + * + * This should be used to allocate a new SPI device from and ACPI Device node. + * The caller is responsible for calling spi_add_device to register the SPI device. + * + * If ctlr is set to NULL, the Controller for the SPI device will be looked up + * using the resource. + * If index is set to -1, index is not used. + * Note: If index is -1, ctlr must be set. + * + * Return: a pointer to the new device, or ERR_PTR on error. + */ +struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr, + struct acpi_device *adev, + int index) { + acpi_handle parent_handle = NULL; struct list_head resource_list; + struct acpi_spi_lookup lookup = {}; struct spi_device *spi; int ret; - if (acpi_bus_get_status(adev) || !adev->status.present || - acpi_device_enumerated(adev)) - return AE_OK; + if (!ctlr && index == -1) + return ERR_PTR(-EINVAL); - spi = spi_alloc_device(ctlr); + lookup.ctlr = ctlr; + lookup.irq = -1; + lookup.index = index; + lookup.n = 0; + + INIT_LIST_HEAD(&resource_list); + ret = acpi_dev_get_resources(adev, &resource_list, + acpi_spi_add_resource, &lookup); + acpi_dev_free_resource_list(&resource_list); + + if (ret < 0) + /* Found SPI in _CRS but it points to another controller */ + return ERR_PTR(ret); + + if (!lookup.max_speed_hz && + ACPI_SUCCESS(acpi_get_parent(adev->handle, &parent_handle)) && + device_match_acpi_handle(lookup.ctlr->dev.parent, parent_handle)) { + /* Apple does not use _CRS but nested devices for SPI target devices */ + acpi_spi_parse_apple_properties(adev, &lookup); + } + + if (!lookup.max_speed_hz) + return ERR_PTR(-ENODEV); + + spi = spi_alloc_device(lookup.ctlr); if (!spi) { - dev_err(&ctlr->dev, "failed to allocate SPI device for %s\n", + dev_err(&lookup.ctlr->dev, "failed to allocate SPI device for %s\n", dev_name(&adev->dev)); - return AE_NO_MEMORY; + return ERR_PTR(-ENOMEM); } + spi_set_chipselect(spi, 0, lookup.chip_select); + ACPI_COMPANION_SET(&spi->dev, adev); - spi->irq = -1; + spi->max_speed_hz = lookup.max_speed_hz; + spi->mode |= lookup.mode; + spi->irq = lookup.irq; + spi->bits_per_word = lookup.bits_per_word; + /* + * By default spi->chip_select[0] will hold the physical CS number, + * so set bit 0 in spi->cs_index_mask. + */ + spi->cs_index_mask = BIT(0); - INIT_LIST_HEAD(&resource_list); - ret = acpi_dev_get_resources(adev, &resource_list, - acpi_spi_add_resource, spi); - acpi_dev_free_resource_list(&resource_list); + return spi; +} +EXPORT_SYMBOL_GPL(acpi_spi_device_alloc); - acpi_spi_parse_apple_properties(spi); +static acpi_status acpi_register_spi_device(struct spi_controller *ctlr, + struct acpi_device *adev) +{ + struct spi_device *spi; - if (ret < 0 || !spi->max_speed_hz) { - spi_dev_put(spi); + if (acpi_bus_get_status(adev) || !adev->status.present || + acpi_device_enumerated(adev)) return AE_OK; + + spi = acpi_spi_device_alloc(ctlr, adev, -1); + if (IS_ERR(spi)) { + if (PTR_ERR(spi) == -ENOMEM) + return AE_NO_MEMORY; + else + return AE_OK; } acpi_set_modalias(adev, acpi_device_hid(adev), spi->modalias, sizeof(spi->modalias)); + /* + * This gets re-tried in spi_probe() for -EPROBE_DEFER handling in case + * the GPIO controller does not have a driver yet. This needs to be done + * here too, because this call sets the GPIO direction and/or bias. + * Setting these needs to be done even if there is no driver, in which + * case spi_probe() will never get called. + * TODO: ideally the setup of the GPIO should be handled in a generic + * manner in the ACPI/gpiolib core code. + */ if (spi->irq < 0) spi->irq = acpi_dev_gpio_irq_get(adev, 0); @@ -1903,15 +2879,17 @@ static acpi_status acpi_register_spi_device(struct spi_controller *ctlr, static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level, void *data, void **return_value) { + struct acpi_device *adev = acpi_fetch_acpi_dev(handle); struct spi_controller *ctlr = data; - struct acpi_device *adev; - if (acpi_bus_get_device(handle, &adev)) + if (!adev) return AE_OK; return acpi_register_spi_device(ctlr, adev); } +#define SPI_ACPI_ENUMERATE_MAX_DEPTH 32 + static void acpi_register_spi_devices(struct spi_controller *ctlr) { acpi_status status; @@ -1921,10 +2899,11 @@ static void acpi_register_spi_devices(struct spi_controller *ctlr) if (!handle) return; - status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, + SPI_ACPI_ENUMERATE_MAX_DEPTH, acpi_spi_add_device, NULL, ctlr, NULL); if (ACPI_FAILURE(status)) - dev_warn(&ctlr->dev, "failed to enumerate SPI slaves\n"); + dev_warn(&ctlr->dev, "failed to enumerate SPI target devices\n"); } #else static inline void acpi_register_spi_devices(struct spi_controller *ctlr) {} @@ -1938,50 +2917,45 @@ static void spi_controller_release(struct device *dev) kfree(ctlr); } -static struct class spi_master_class = { +static const struct class spi_controller_class = { .name = "spi_master", - .owner = THIS_MODULE, .dev_release = spi_controller_release, - .dev_groups = spi_master_groups, + .dev_groups = spi_controller_groups, }; #ifdef CONFIG_SPI_SLAVE /** - * spi_slave_abort - abort the ongoing transfer request on an SPI slave - * controller + * spi_target_abort - abort the ongoing transfer request on an SPI target controller * @spi: device used for the current transfer */ -int spi_slave_abort(struct spi_device *spi) +int spi_target_abort(struct spi_device *spi) { struct spi_controller *ctlr = spi->controller; - if (spi_controller_is_slave(ctlr) && ctlr->slave_abort) - return ctlr->slave_abort(ctlr); + if (spi_controller_is_target(ctlr) && ctlr->target_abort) + return ctlr->target_abort(ctlr); return -ENOTSUPP; } -EXPORT_SYMBOL_GPL(spi_slave_abort); +EXPORT_SYMBOL_GPL(spi_target_abort); -static int match_true(struct device *dev, void *data) -{ - return 1; -} - -static ssize_t spi_slave_show(struct device *dev, - struct device_attribute *attr, char *buf) +static ssize_t slave_show(struct device *dev, struct device_attribute *attr, + char *buf) { struct spi_controller *ctlr = container_of(dev, struct spi_controller, dev); struct device *child; + int ret; + + child = device_find_any_child(&ctlr->dev); + ret = sysfs_emit(buf, "%s\n", child ? to_spi_device(child)->modalias : NULL); + put_device(child); - child = device_find_child(&ctlr->dev, NULL, match_true); - return sprintf(buf, "%s\n", - child ? to_spi_device(child)->modalias : NULL); + return ret; } -static ssize_t spi_slave_store(struct device *dev, - struct device_attribute *attr, const char *buf, - size_t count) +static ssize_t slave_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) { struct spi_controller *ctlr = container_of(dev, struct spi_controller, dev); @@ -1994,20 +2968,20 @@ static ssize_t spi_slave_store(struct device *dev, if (rc != 1 || !name[0]) return -EINVAL; - child = device_find_child(&ctlr->dev, NULL, match_true); + child = device_find_any_child(&ctlr->dev); if (child) { - /* Remove registered slave */ + /* Remove registered target device */ device_unregister(child); put_device(child); } if (strcmp(name, "(null)")) { - /* Register new slave */ + /* Register new target device */ spi = spi_alloc_device(ctlr); if (!spi) return -ENOMEM; - strlcpy(spi->modalias, name, sizeof(spi->modalias)); + strscpy(spi->modalias, name, sizeof(spi->modalias)); rc = spi_add_device(spi); if (rc) { @@ -2019,41 +2993,42 @@ static ssize_t spi_slave_store(struct device *dev, return count; } -static DEVICE_ATTR(slave, 0644, spi_slave_show, spi_slave_store); +static DEVICE_ATTR_RW(slave); -static struct attribute *spi_slave_attrs[] = { +static struct attribute *spi_target_attrs[] = { &dev_attr_slave.attr, NULL, }; -static const struct attribute_group spi_slave_group = { - .attrs = spi_slave_attrs, +static const struct attribute_group spi_target_group = { + .attrs = spi_target_attrs, }; -static const struct attribute_group *spi_slave_groups[] = { +static const struct attribute_group *spi_target_groups[] = { &spi_controller_statistics_group, - &spi_slave_group, + &spi_target_group, NULL, }; -static struct class spi_slave_class = { +static const struct class spi_target_class = { .name = "spi_slave", - .owner = THIS_MODULE, .dev_release = spi_controller_release, - .dev_groups = spi_slave_groups, + .dev_groups = spi_target_groups, }; #else -extern struct class spi_slave_class; /* dummy */ +extern struct class spi_target_class; /* dummy */ #endif /** - * __spi_alloc_controller - allocate an SPI master or slave controller + * __spi_alloc_controller - allocate an SPI host or target controller * @dev: the controller, possibly using the platform_bus * @size: how much zeroed driver-private data to allocate; the pointer to this - * memory is in the driver_data field of the returned device, - * accessible with spi_controller_get_devdata(). - * @slave: flag indicating whether to allocate an SPI master (false) or SPI - * slave (true) controller + * memory is in the driver_data field of the returned device, accessible + * with spi_controller_get_devdata(); the memory is cacheline aligned; + * drivers granting DMA access to portions of their private data need to + * round up @size using ALIGN(size, dma_get_cache_alignment()). + * @target: flag indicating whether to allocate an SPI host (false) or SPI target (true) + * controller * Context: can sleep * * This call is used only by SPI controller drivers, which are the @@ -2070,72 +3045,158 @@ extern struct class spi_slave_class; /* dummy */ * Return: the SPI controller structure on success, else NULL. */ struct spi_controller *__spi_alloc_controller(struct device *dev, - unsigned int size, bool slave) + unsigned int size, bool target) { struct spi_controller *ctlr; + size_t ctlr_size = ALIGN(sizeof(*ctlr), dma_get_cache_alignment()); if (!dev) return NULL; - ctlr = kzalloc(size + sizeof(*ctlr), GFP_KERNEL); + ctlr = kzalloc(size + ctlr_size, GFP_KERNEL); if (!ctlr) return NULL; device_initialize(&ctlr->dev); + INIT_LIST_HEAD(&ctlr->queue); + spin_lock_init(&ctlr->queue_lock); + spin_lock_init(&ctlr->bus_lock_spinlock); + mutex_init(&ctlr->bus_lock_mutex); + mutex_init(&ctlr->io_mutex); + mutex_init(&ctlr->add_lock); ctlr->bus_num = -1; ctlr->num_chipselect = 1; - ctlr->slave = slave; - if (IS_ENABLED(CONFIG_SPI_SLAVE) && slave) - ctlr->dev.class = &spi_slave_class; + ctlr->target = target; + if (IS_ENABLED(CONFIG_SPI_SLAVE) && target) + ctlr->dev.class = &spi_target_class; else - ctlr->dev.class = &spi_master_class; + ctlr->dev.class = &spi_controller_class; ctlr->dev.parent = dev; pm_suspend_ignore_children(&ctlr->dev, true); - spi_controller_set_devdata(ctlr, &ctlr[1]); + spi_controller_set_devdata(ctlr, (void *)ctlr + ctlr_size); return ctlr; } EXPORT_SYMBOL_GPL(__spi_alloc_controller); -#ifdef CONFIG_OF -static int of_spi_register_master(struct spi_controller *ctlr) +static void devm_spi_release_controller(struct device *dev, void *ctlr) { - int nb, i, *cs; - struct device_node *np = ctlr->dev.of_node; + spi_controller_put(*(struct spi_controller **)ctlr); +} - if (!np) - return 0; +/** + * __devm_spi_alloc_controller - resource-managed __spi_alloc_controller() + * @dev: physical device of SPI controller + * @size: how much zeroed driver-private data to allocate + * @target: whether to allocate an SPI host (false) or SPI target (true) controller + * Context: can sleep + * + * Allocate an SPI controller and automatically release a reference on it + * when @dev is unbound from its driver. Drivers are thus relieved from + * having to call spi_controller_put(). + * + * The arguments to this function are identical to __spi_alloc_controller(). + * + * Return: the SPI controller structure on success, else NULL. + */ +struct spi_controller *__devm_spi_alloc_controller(struct device *dev, + unsigned int size, + bool target) +{ + struct spi_controller **ptr, *ctlr; - nb = of_gpio_named_count(np, "cs-gpios"); - ctlr->num_chipselect = max_t(int, nb, ctlr->num_chipselect); + ptr = devres_alloc(devm_spi_release_controller, sizeof(*ptr), + GFP_KERNEL); + if (!ptr) + return NULL; - /* Return error only for an incorrectly formed cs-gpios property */ - if (nb == 0 || nb == -ENOENT) - return 0; - else if (nb < 0) + ctlr = __spi_alloc_controller(dev, size, target); + if (ctlr) { + ctlr->devm_allocated = true; + *ptr = ctlr; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return ctlr; +} +EXPORT_SYMBOL_GPL(__devm_spi_alloc_controller); + +/** + * spi_get_gpio_descs() - grab chip select GPIOs for the controller + * @ctlr: The SPI controller to grab GPIO descriptors for + */ +static int spi_get_gpio_descs(struct spi_controller *ctlr) +{ + int nb, i; + struct gpio_desc **cs; + struct device *dev = &ctlr->dev; + unsigned long native_cs_mask = 0; + unsigned int num_cs_gpios = 0; + + nb = gpiod_count(dev, "cs"); + if (nb < 0) { + /* No GPIOs at all is fine, else return the error */ + if (nb == -ENOENT) + return 0; return nb; + } - cs = devm_kcalloc(&ctlr->dev, ctlr->num_chipselect, sizeof(int), - GFP_KERNEL); - ctlr->cs_gpios = cs; + ctlr->num_chipselect = max_t(int, nb, ctlr->num_chipselect); - if (!ctlr->cs_gpios) + cs = devm_kcalloc(dev, ctlr->num_chipselect, sizeof(*cs), + GFP_KERNEL); + if (!cs) return -ENOMEM; + ctlr->cs_gpiods = cs; - for (i = 0; i < ctlr->num_chipselect; i++) - cs[i] = -ENOENT; + for (i = 0; i < nb; i++) { + /* + * Most chipselects are active low, the inverted + * semantics are handled by special quirks in gpiolib, + * so initializing them GPIOD_OUT_LOW here means + * "unasserted", in most cases this will drive the physical + * line high. + */ + cs[i] = devm_gpiod_get_index_optional(dev, "cs", i, + GPIOD_OUT_LOW); + if (IS_ERR(cs[i])) + return PTR_ERR(cs[i]); - for (i = 0; i < nb; i++) - cs[i] = of_get_named_gpio(np, "cs-gpios", i); + if (cs[i]) { + /* + * If we find a CS GPIO, name it after the device and + * chip select line. + */ + char *gpioname; + + gpioname = devm_kasprintf(dev, GFP_KERNEL, "%s CS%d", + dev_name(dev), i); + if (!gpioname) + return -ENOMEM; + gpiod_set_consumer_name(cs[i], gpioname); + num_cs_gpios++; + continue; + } + + if (ctlr->max_native_cs && i >= ctlr->max_native_cs) { + dev_err(dev, "Invalid native chip select %d\n", i); + return -EINVAL; + } + native_cs_mask |= BIT(i); + } + + ctlr->unused_native_cs = ffs(~native_cs_mask) - 1; + + if ((ctlr->flags & SPI_CONTROLLER_GPIO_SS) && num_cs_gpios && + ctlr->max_native_cs && ctlr->unused_native_cs >= ctlr->max_native_cs) { + dev_err(dev, "No unused native chip select available\n"); + return -EINVAL; + } return 0; } -#else -static int of_spi_register_master(struct spi_controller *ctlr) -{ - return 0; -} -#endif static int spi_controller_check_ops(struct spi_controller *ctlr) { @@ -2143,24 +3204,37 @@ static int spi_controller_check_ops(struct spi_controller *ctlr) * The controller may implement only the high-level SPI-memory like * operations if it does not support regular SPI transfers, and this is * valid use case. - * If ->mem_ops is NULL, we request that at least one of the - * ->transfer_xxx() method be implemented. + * If ->mem_ops or ->mem_ops->exec_op is NULL, we request that at least + * one of the ->transfer_xxx() method be implemented. */ - if (ctlr->mem_ops) { - if (!ctlr->mem_ops->exec_op) - return -EINVAL; - } else if (!ctlr->transfer && !ctlr->transfer_one && + if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) { + if (!ctlr->transfer && !ctlr->transfer_one && !ctlr->transfer_one_message) { - return -EINVAL; + return -EINVAL; + } } return 0; } +/* Allocate dynamic bus number using Linux idr */ +static int spi_controller_id_alloc(struct spi_controller *ctlr, int start, int end) +{ + int id; + + mutex_lock(&board_lock); + id = idr_alloc(&spi_controller_idr, ctlr, start, end, GFP_KERNEL); + mutex_unlock(&board_lock); + if (WARN(id < 0, "couldn't get idr")) + return id == -ENOSPC ? -EBUSY : id; + ctlr->bus_num = id; + return 0; +} + /** - * spi_register_controller - register SPI master or slave controller - * @ctlr: initialized master, originally from spi_alloc_master() or - * spi_alloc_slave() + * spi_register_controller - register SPI host or target controller + * @ctlr: initialized controller, originally from spi_alloc_host() or + * spi_alloc_target() * Context: can sleep * * SPI controllers connect to their drivers using some non-SPI bus, @@ -2184,8 +3258,9 @@ int spi_register_controller(struct spi_controller *ctlr) { struct device *dev = ctlr->dev.parent; struct boardinfo *bi; - int status = -ENODEV; - int id, first_dynamic; + int first_dynamic; + int status; + int idx; if (!dev) return -ENODEV; @@ -2198,39 +3273,14 @@ int spi_register_controller(struct spi_controller *ctlr) if (status) return status; - if (!spi_controller_is_slave(ctlr)) { - status = of_spi_register_master(ctlr); + if (ctlr->bus_num < 0) + ctlr->bus_num = of_alias_get_id(ctlr->dev.of_node, "spi"); + if (ctlr->bus_num >= 0) { + /* Devices with a fixed bus num must check-in with the num */ + status = spi_controller_id_alloc(ctlr, ctlr->bus_num, ctlr->bus_num + 1); if (status) return status; } - - /* even if it's just one always-selected device, there must - * be at least one chipselect - */ - if (ctlr->num_chipselect == 0) - return -EINVAL; - if (ctlr->bus_num >= 0) { - /* devices with a fixed bus num must check-in with the num */ - mutex_lock(&board_lock); - id = idr_alloc(&spi_master_idr, ctlr, ctlr->bus_num, - ctlr->bus_num + 1, GFP_KERNEL); - mutex_unlock(&board_lock); - if (WARN(id < 0, "couldn't get idr")) - return id == -ENOSPC ? -EBUSY : id; - ctlr->bus_num = id; - } else if (ctlr->dev.of_node) { - /* allocate dynamic bus number using Linux idr */ - id = of_alias_get_id(ctlr->dev.of_node, "spi"); - if (id >= 0) { - ctlr->bus_num = id; - mutex_lock(&board_lock); - id = idr_alloc(&spi_master_idr, ctlr, ctlr->bus_num, - ctlr->bus_num + 1, GFP_KERNEL); - mutex_unlock(&board_lock); - if (WARN(id < 0, "couldn't get idr")) - return id == -ENOSPC ? -EBUSY : id; - } - } if (ctlr->bus_num < 0) { first_dynamic = of_alias_get_highest_id("spi"); if (first_dynamic < 0) @@ -2238,38 +3288,51 @@ int spi_register_controller(struct spi_controller *ctlr) else first_dynamic++; - mutex_lock(&board_lock); - id = idr_alloc(&spi_master_idr, ctlr, first_dynamic, - 0, GFP_KERNEL); - mutex_unlock(&board_lock); - if (WARN(id < 0, "couldn't get idr")) - return id; - ctlr->bus_num = id; + status = spi_controller_id_alloc(ctlr, first_dynamic, 0); + if (status) + return status; } - INIT_LIST_HEAD(&ctlr->queue); - spin_lock_init(&ctlr->queue_lock); - spin_lock_init(&ctlr->bus_lock_spinlock); - mutex_init(&ctlr->bus_lock_mutex); - mutex_init(&ctlr->io_mutex); ctlr->bus_lock_flag = 0; init_completion(&ctlr->xfer_completion); + init_completion(&ctlr->cur_msg_completion); if (!ctlr->max_dma_len) ctlr->max_dma_len = INT_MAX; - /* register the device, then userspace will see it. - * registration fails if the bus ID is in use. + /* + * Register the device, then userspace will see it. + * Registration fails if the bus ID is in use. */ dev_set_name(&ctlr->dev, "spi%u", ctlr->bus_num); - status = device_add(&ctlr->dev); - if (status < 0) { - /* free bus id */ - mutex_lock(&board_lock); - idr_remove(&spi_master_idr, ctlr->bus_num); - mutex_unlock(&board_lock); - goto done; + + if (!spi_controller_is_target(ctlr) && ctlr->use_gpio_descriptors) { + status = spi_get_gpio_descs(ctlr); + if (status) + goto free_bus_id; + /* + * A controller using GPIO descriptors always + * supports SPI_CS_HIGH if need be. + */ + ctlr->mode_bits |= SPI_CS_HIGH; + } + + /* + * Even if it's just one always-selected device, there must + * be at least one chipselect. + */ + if (!ctlr->num_chipselect) { + status = -EINVAL; + goto free_bus_id; } + + /* Setting last_cs to SPI_INVALID_CS means no chip selected */ + for (idx = 0; idx < SPI_DEVICE_CS_CNT_MAX; idx++) + ctlr->last_cs[idx] = SPI_INVALID_CS; + + status = device_add(&ctlr->dev); + if (status < 0) + goto free_bus_id; dev_dbg(dev, "registered %s %s\n", - spi_controller_is_slave(ctlr) ? "slave" : "master", + spi_controller_is_target(ctlr) ? "target" : "host", dev_name(&ctlr->dev)); /* @@ -2283,15 +3346,16 @@ int spi_register_controller(struct spi_controller *ctlr) status = spi_controller_initialize_queue(ctlr); if (status) { device_del(&ctlr->dev); - /* free bus id */ - mutex_lock(&board_lock); - idr_remove(&spi_master_idr, ctlr->bus_num); - mutex_unlock(&board_lock); - goto done; + goto free_bus_id; } } - /* add statistics */ - spin_lock_init(&ctlr->statistics.lock); + /* Add statistics */ + ctlr->pcpu_statistics = spi_alloc_pcpu_stats(dev); + if (!ctlr->pcpu_statistics) { + dev_err(dev, "Error allocating per-cpu statistics\n"); + status = -ENOMEM; + goto destroy_queue; + } mutex_lock(&board_lock); list_add_tail(&ctlr->list, &spi_controller_list); @@ -2302,7 +3366,14 @@ int spi_register_controller(struct spi_controller *ctlr) /* Register devices from the device tree and ACPI */ of_register_spi_devices(ctlr); acpi_register_spi_devices(ctlr); -done: + return status; + +destroy_queue: + spi_destroy_queue(ctlr); +free_bus_id: + mutex_lock(&board_lock); + idr_remove(&spi_controller_idr, ctlr->bus_num); + mutex_unlock(&board_lock); return status; } EXPORT_SYMBOL_GPL(spi_register_controller); @@ -2313,11 +3384,10 @@ static void devm_spi_unregister(struct device *dev, void *res) } /** - * devm_spi_register_controller - register managed SPI master or slave - * controller + * devm_spi_register_controller - register managed SPI host or target controller * @dev: device managing SPI controller - * @ctlr: initialized controller, originally from spi_alloc_master() or - * spi_alloc_slave() + * @ctlr: initialized controller, originally from spi_alloc_host() or + * spi_alloc_target() * Context: can sleep * * Register a SPI device as with spi_register_controller() which will @@ -2354,7 +3424,7 @@ static int __unregister(struct device *dev, void *null) } /** - * spi_unregister_controller - unregister SPI master or slave controller + * spi_unregister_controller - unregister SPI host or target controller * @ctlr: the controller being unregistered * Context: can sleep * @@ -2369,11 +3439,16 @@ void spi_unregister_controller(struct spi_controller *ctlr) { struct spi_controller *found; int id = ctlr->bus_num; - int dummy; + + /* Prevent addition of new devices, unregister existing ones */ + if (IS_ENABLED(CONFIG_SPI_DYNAMIC)) + mutex_lock(&ctlr->add_lock); + + device_for_each_child(&ctlr->dev, NULL, __unregister); /* First make sure that this controller was ever added */ mutex_lock(&board_lock); - found = idr_find(&spi_master_idr, id); + found = idr_find(&spi_controller_idr, id); mutex_unlock(&board_lock); if (ctlr->queued) { if (spi_destroy_queue(ctlr)) @@ -2383,170 +3458,75 @@ void spi_unregister_controller(struct spi_controller *ctlr) list_del(&ctlr->list); mutex_unlock(&board_lock); - dummy = device_for_each_child(&ctlr->dev, NULL, __unregister); - device_unregister(&ctlr->dev); - /* free bus id */ + device_del(&ctlr->dev); + + /* Free bus id */ mutex_lock(&board_lock); if (found == ctlr) - idr_remove(&spi_master_idr, id); + idr_remove(&spi_controller_idr, id); mutex_unlock(&board_lock); -} -EXPORT_SYMBOL_GPL(spi_unregister_controller); - -int spi_controller_suspend(struct spi_controller *ctlr) -{ - int ret; - /* Basically no-ops for non-queued controllers */ - if (!ctlr->queued) - return 0; - - ret = spi_stop_queue(ctlr); - if (ret) - dev_err(&ctlr->dev, "queue stop failed\n"); + if (IS_ENABLED(CONFIG_SPI_DYNAMIC)) + mutex_unlock(&ctlr->add_lock); - return ret; -} -EXPORT_SYMBOL_GPL(spi_controller_suspend); - -int spi_controller_resume(struct spi_controller *ctlr) -{ - int ret; - - if (!ctlr->queued) - return 0; - - ret = spi_start_queue(ctlr); - if (ret) - dev_err(&ctlr->dev, "queue restart failed\n"); - - return ret; + /* + * Release the last reference on the controller if its driver + * has not yet been converted to devm_spi_alloc_host/target(). + */ + if (!ctlr->devm_allocated) + put_device(&ctlr->dev); } -EXPORT_SYMBOL_GPL(spi_controller_resume); +EXPORT_SYMBOL_GPL(spi_unregister_controller); -static int __spi_controller_match(struct device *dev, const void *data) +static inline int __spi_check_suspended(const struct spi_controller *ctlr) { - struct spi_controller *ctlr; - const u16 *bus_num = data; - - ctlr = container_of(dev, struct spi_controller, dev); - return ctlr->bus_num == *bus_num; + return ctlr->flags & SPI_CONTROLLER_SUSPENDED ? -ESHUTDOWN : 0; } -/** - * spi_busnum_to_master - look up master associated with bus_num - * @bus_num: the master's bus number - * Context: can sleep - * - * This call may be used with devices that are registered after - * arch init time. It returns a refcounted pointer to the relevant - * spi_controller (which the caller must release), or NULL if there is - * no such master registered. - * - * Return: the SPI master structure on success, else NULL. - */ -struct spi_controller *spi_busnum_to_master(u16 bus_num) +static inline void __spi_mark_suspended(struct spi_controller *ctlr) { - struct device *dev; - struct spi_controller *ctlr = NULL; - - dev = class_find_device(&spi_master_class, NULL, &bus_num, - __spi_controller_match); - if (dev) - ctlr = container_of(dev, struct spi_controller, dev); - /* reference got in class_find_device */ - return ctlr; + mutex_lock(&ctlr->bus_lock_mutex); + ctlr->flags |= SPI_CONTROLLER_SUSPENDED; + mutex_unlock(&ctlr->bus_lock_mutex); } -EXPORT_SYMBOL_GPL(spi_busnum_to_master); -/*-------------------------------------------------------------------------*/ - -/* Core methods for SPI resource management */ - -/** - * spi_res_alloc - allocate a spi resource that is life-cycle managed - * during the processing of a spi_message while using - * spi_transfer_one - * @spi: the spi device for which we allocate memory - * @release: the release code to execute for this resource - * @size: size to alloc and return - * @gfp: GFP allocation flags - * - * Return: the pointer to the allocated data - * - * This may get enhanced in the future to allocate from a memory pool - * of the @spi_device or @spi_controller to avoid repeated allocations. - */ -void *spi_res_alloc(struct spi_device *spi, - spi_res_release_t release, - size_t size, gfp_t gfp) +static inline void __spi_mark_resumed(struct spi_controller *ctlr) { - struct spi_res *sres; - - sres = kzalloc(sizeof(*sres) + size, gfp); - if (!sres) - return NULL; - - INIT_LIST_HEAD(&sres->entry); - sres->release = release; - - return sres->data; + mutex_lock(&ctlr->bus_lock_mutex); + ctlr->flags &= ~SPI_CONTROLLER_SUSPENDED; + mutex_unlock(&ctlr->bus_lock_mutex); } -EXPORT_SYMBOL_GPL(spi_res_alloc); -/** - * spi_res_free - free an spi resource - * @res: pointer to the custom data of a resource - * - */ -void spi_res_free(void *res) +int spi_controller_suspend(struct spi_controller *ctlr) { - struct spi_res *sres = container_of(res, struct spi_res, data); - - if (!res) - return; - - WARN_ON(!list_empty(&sres->entry)); - kfree(sres); -} -EXPORT_SYMBOL_GPL(spi_res_free); + int ret = 0; -/** - * spi_res_add - add a spi_res to the spi_message - * @message: the spi message - * @res: the spi_resource - */ -void spi_res_add(struct spi_message *message, void *res) -{ - struct spi_res *sres = container_of(res, struct spi_res, data); + /* Basically no-ops for non-queued controllers */ + if (ctlr->queued) { + ret = spi_stop_queue(ctlr); + if (ret) + dev_err(&ctlr->dev, "queue stop failed\n"); + } - WARN_ON(!list_empty(&sres->entry)); - list_add_tail(&sres->entry, &message->resources); + __spi_mark_suspended(ctlr); + return ret; } -EXPORT_SYMBOL_GPL(spi_res_add); +EXPORT_SYMBOL_GPL(spi_controller_suspend); -/** - * spi_res_release - release all spi resources for this message - * @ctlr: the @spi_controller - * @message: the @spi_message - */ -void spi_res_release(struct spi_controller *ctlr, struct spi_message *message) +int spi_controller_resume(struct spi_controller *ctlr) { - struct spi_res *res; - - while (!list_empty(&message->resources)) { - res = list_last_entry(&message->resources, - struct spi_res, entry); - - if (res->release) - res->release(ctlr, message, res->data); + int ret = 0; - list_del(&res->entry); + __spi_mark_resumed(ctlr); - kfree(res); + if (ctlr->queued) { + ret = spi_start_queue(ctlr); + if (ret) + dev_err(&ctlr->dev, "queue restart failed\n"); } + return ret; } -EXPORT_SYMBOL_GPL(spi_res_release); +EXPORT_SYMBOL_GPL(spi_controller_resume); /*-------------------------------------------------------------------------*/ @@ -2559,14 +3539,14 @@ static void __spi_replace_transfers_release(struct spi_controller *ctlr, struct spi_replaced_transfers *rxfer = res; size_t i; - /* call extra callback if requested */ + /* Call extra callback if requested */ if (rxfer->release) rxfer->release(ctlr, msg, res); - /* insert replaced transfers back into the message */ + /* Insert replaced transfers back into the message */ list_splice(&rxfer->replaced_transfers, rxfer->replaced_after); - /* remove the formerly inserted entries */ + /* Remove the formerly inserted entries */ for (i = 0; i < rxfer->inserted; i++) list_del(&rxfer->inserted_transfers[i].transfer_list); } @@ -2586,7 +3566,7 @@ static void __spi_replace_transfers_release(struct spi_controller *ctlr, * Returns: pointer to @spi_replaced_transfers, * PTR_ERR(...) in case of errors. */ -struct spi_replaced_transfers *spi_replace_transfers( +static struct spi_replaced_transfers *spi_replace_transfers( struct spi_message *msg, struct spi_transfer *xfer_first, size_t remove, @@ -2599,187 +3579,182 @@ struct spi_replaced_transfers *spi_replace_transfers( struct spi_transfer *xfer; size_t i; - /* allocate the structure using spi_res */ + /* Allocate the structure using spi_res */ rxfer = spi_res_alloc(msg->spi, __spi_replace_transfers_release, - insert * sizeof(struct spi_transfer) - + sizeof(struct spi_replaced_transfers) + struct_size(rxfer, inserted_transfers, insert) + extradatasize, gfp); if (!rxfer) return ERR_PTR(-ENOMEM); - /* the release code to invoke before running the generic release */ + /* The release code to invoke before running the generic release */ rxfer->release = release; - /* assign extradata */ + /* Assign extradata */ if (extradatasize) rxfer->extradata = &rxfer->inserted_transfers[insert]; - /* init the replaced_transfers list */ + /* Init the replaced_transfers list */ INIT_LIST_HEAD(&rxfer->replaced_transfers); - /* assign the list_entry after which we should reinsert + /* + * Assign the list_entry after which we should reinsert * the @replaced_transfers - it may be spi_message.messages! */ rxfer->replaced_after = xfer_first->transfer_list.prev; - /* remove the requested number of transfers */ + /* Remove the requested number of transfers */ for (i = 0; i < remove; i++) { - /* if the entry after replaced_after it is msg->transfers + /* + * If the entry after replaced_after it is msg->transfers * then we have been requested to remove more transfers - * than are in the list + * than are in the list. */ if (rxfer->replaced_after->next == &msg->transfers) { dev_err(&msg->spi->dev, "requested to remove more spi_transfers than are available\n"); - /* insert replaced transfers back into the message */ + /* Insert replaced transfers back into the message */ list_splice(&rxfer->replaced_transfers, rxfer->replaced_after); - /* free the spi_replace_transfer structure */ + /* Free the spi_replace_transfer structure... */ spi_res_free(rxfer); - /* and return with an error */ + /* ...and return with an error */ return ERR_PTR(-EINVAL); } - /* remove the entry after replaced_after from list of - * transfers and add it to list of replaced_transfers + /* + * Remove the entry after replaced_after from list of + * transfers and add it to list of replaced_transfers. */ list_move_tail(rxfer->replaced_after->next, &rxfer->replaced_transfers); } - /* create copy of the given xfer with identical settings - * based on the first transfer to get removed + /* + * Create copy of the given xfer with identical settings + * based on the first transfer to get removed. */ for (i = 0; i < insert; i++) { - /* we need to run in reverse order */ + /* We need to run in reverse order */ xfer = &rxfer->inserted_transfers[insert - 1 - i]; - /* copy all spi_transfer data */ + /* Copy all spi_transfer data */ memcpy(xfer, xfer_first, sizeof(*xfer)); - /* add to list */ + /* Add to list */ list_add(&xfer->transfer_list, rxfer->replaced_after); - /* clear cs_change and delay_usecs for all but the last */ + /* Clear cs_change and delay for all but the last */ if (i) { xfer->cs_change = false; - xfer->delay_usecs = 0; + xfer->delay.value = 0; } } - /* set up inserted */ + /* Set up inserted... */ rxfer->inserted = insert; - /* and register it with spi_res/spi_message */ + /* ...and register it with spi_res/spi_message */ spi_res_add(msg, rxfer); return rxfer; } -EXPORT_SYMBOL_GPL(spi_replace_transfers); static int __spi_split_transfer_maxsize(struct spi_controller *ctlr, struct spi_message *msg, struct spi_transfer **xferp, - size_t maxsize, - gfp_t gfp) + size_t maxsize) { struct spi_transfer *xfer = *xferp, *xfers; struct spi_replaced_transfers *srt; size_t offset; size_t count, i; - /* warn once about this fact that we are splitting a transfer */ - dev_warn_once(&msg->spi->dev, - "spi_transfer of length %i exceed max length of %zu - needed to split transfers\n", - xfer->len, maxsize); - - /* calculate how many we have to replace */ + /* Calculate how many we have to replace */ count = DIV_ROUND_UP(xfer->len, maxsize); - /* create replacement */ - srt = spi_replace_transfers(msg, xfer, 1, count, NULL, 0, gfp); + /* Create replacement */ + srt = spi_replace_transfers(msg, xfer, 1, count, NULL, 0, GFP_KERNEL); if (IS_ERR(srt)) return PTR_ERR(srt); xfers = srt->inserted_transfers; - /* now handle each of those newly inserted spi_transfers - * note that the replacements spi_transfers all are preset + /* + * Now handle each of those newly inserted spi_transfers. + * Note that the replacements spi_transfers all are preset * to the same values as *xferp, so tx_buf, rx_buf and len * are all identical (as well as most others) * so we just have to fix up len and the pointers. - * - * this also includes support for the depreciated - * spi_message.is_dma_mapped interface */ - /* the first transfer just needs the length modified, so we - * run it outside the loop + /* + * The first transfer just needs the length modified, so we + * run it outside the loop. */ xfers[0].len = min_t(size_t, maxsize, xfer[0].len); - /* all the others need rx_buf/tx_buf also set */ + /* All the others need rx_buf/tx_buf also set */ for (i = 1, offset = maxsize; i < count; offset += maxsize, i++) { - /* update rx_buf, tx_buf and dma */ + /* Update rx_buf, tx_buf and DMA */ if (xfers[i].rx_buf) xfers[i].rx_buf += offset; - if (xfers[i].rx_dma) - xfers[i].rx_dma += offset; if (xfers[i].tx_buf) xfers[i].tx_buf += offset; - if (xfers[i].tx_dma) - xfers[i].tx_dma += offset; - /* update length */ + /* Update length */ xfers[i].len = min(maxsize, xfers[i].len - offset); } - /* we set up xferp to the last entry we have inserted, - * so that we skip those already split transfers + /* + * We set up xferp to the last entry we have inserted, + * so that we skip those already split transfers. */ *xferp = &xfers[count - 1]; - /* increment statistics counters */ - SPI_STATISTICS_INCREMENT_FIELD(&ctlr->statistics, + /* Increment statistics counters */ + SPI_STATISTICS_INCREMENT_FIELD(ctlr->pcpu_statistics, transfers_split_maxsize); - SPI_STATISTICS_INCREMENT_FIELD(&msg->spi->statistics, + SPI_STATISTICS_INCREMENT_FIELD(msg->spi->pcpu_statistics, transfers_split_maxsize); return 0; } /** - * spi_split_tranfers_maxsize - split spi transfers into multiple transfers - * when an individual transfer exceeds a - * certain size + * spi_split_transfers_maxsize - split spi transfers into multiple transfers + * when an individual transfer exceeds a + * certain size * @ctlr: the @spi_controller for this transfer * @msg: the @spi_message to transform * @maxsize: the maximum when to apply this - * @gfp: GFP allocation flags + * + * This function allocates resources that are automatically freed during the + * spi message unoptimize phase so this function should only be called from + * optimize_message callbacks. * * Return: status of transformation */ int spi_split_transfers_maxsize(struct spi_controller *ctlr, struct spi_message *msg, - size_t maxsize, - gfp_t gfp) + size_t maxsize) { struct spi_transfer *xfer; int ret; - /* iterate over the transfer_list, + /* + * Iterate over the transfer_list, * but note that xfer is advanced to the last transfer inserted * to avoid checking sizes again unnecessarily (also xfer does - * potentiall belong to a different list by the time the - * replacement has happened + * potentially belong to a different list by the time the + * replacement has happened). */ list_for_each_entry(xfer, &msg->transfers, transfer_list) { if (xfer->len > maxsize) { ret = __spi_split_transfer_maxsize(ctlr, msg, &xfer, - maxsize, gfp); + maxsize); if (ret) return ret; } @@ -2789,9 +3764,55 @@ int spi_split_transfers_maxsize(struct spi_controller *ctlr, } EXPORT_SYMBOL_GPL(spi_split_transfers_maxsize); + +/** + * spi_split_transfers_maxwords - split SPI transfers into multiple transfers + * when an individual transfer exceeds a + * certain number of SPI words + * @ctlr: the @spi_controller for this transfer + * @msg: the @spi_message to transform + * @maxwords: the number of words to limit each transfer to + * + * This function allocates resources that are automatically freed during the + * spi message unoptimize phase so this function should only be called from + * optimize_message callbacks. + * + * Return: status of transformation + */ +int spi_split_transfers_maxwords(struct spi_controller *ctlr, + struct spi_message *msg, + size_t maxwords) +{ + struct spi_transfer *xfer; + + /* + * Iterate over the transfer_list, + * but note that xfer is advanced to the last transfer inserted + * to avoid checking sizes again unnecessarily (also xfer does + * potentially belong to a different list by the time the + * replacement has happened). + */ + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + size_t maxsize; + int ret; + + maxsize = maxwords * spi_bpw_to_bytes(xfer->bits_per_word); + if (xfer->len > maxsize) { + ret = __spi_split_transfer_maxsize(ctlr, msg, &xfer, + maxsize); + if (ret) + return ret; + } + } + + return 0; +} +EXPORT_SYMBOL_GPL(spi_split_transfers_maxwords); + /*-------------------------------------------------------------------------*/ -/* Core methods for SPI controller protocol drivers. Some of the +/* + * Core methods for SPI controller protocol drivers. Some of the * other core methods are currently defined as inline functions. */ @@ -2810,6 +3831,36 @@ static int __spi_validate_bits_per_word(struct spi_controller *ctlr, } /** + * spi_set_cs_timing - configure CS setup, hold, and inactive delays + * @spi: the device that requires specific CS timing configuration + * + * Return: zero on success, else a negative error code. + */ +static int spi_set_cs_timing(struct spi_device *spi) +{ + struct device *parent = spi->controller->dev.parent; + int status = 0; + + if (spi->controller->set_cs_timing && !spi_get_csgpiod(spi, 0)) { + if (spi->controller->auto_runtime_pm) { + status = pm_runtime_get_sync(parent); + if (status < 0) { + pm_runtime_put_noidle(parent); + dev_err(&spi->controller->dev, "Failed to power device: %d\n", + status); + return status; + } + + status = spi->controller->set_cs_timing(spi); + pm_runtime_put_autosuspend(parent); + } else { + status = spi->controller->set_cs_timing(spi); + } + } + return status; +} + +/** * spi_setup - setup SPI mode and clock rate * @spi: the device whose settings are being modified * Context: can sleep, and no requests are queued to the device @@ -2820,7 +3871,7 @@ static int __spi_validate_bits_per_word(struct spi_controller *ctlr, * changes those settings, and must be called from a context that can sleep. * Except for SPI_CS_HIGH, which takes effect immediately, the changes take * effect the next time the device is selected and data is transferred to - * or from it. When this function returns, the spi device is deselected. + * or from it. When this function returns, the SPI device is deselected. * * Note that this call will fail if the protocol driver specifies an option * that the underlying controller or its driver does not support. For @@ -2834,26 +3885,37 @@ int spi_setup(struct spi_device *spi) unsigned bad_bits, ugly_bits; int status; - /* check mode to prevent that DUAL and QUAD set at the same time + /* + * Check mode to prevent that any two of DUAL, QUAD and NO_MOSI/MISO + * are set at the same time. */ - if (((spi->mode & SPI_TX_DUAL) && (spi->mode & SPI_TX_QUAD)) || - ((spi->mode & SPI_RX_DUAL) && (spi->mode & SPI_RX_QUAD))) { + if ((hweight_long(spi->mode & + (SPI_TX_DUAL | SPI_TX_QUAD | SPI_NO_TX)) > 1) || + (hweight_long(spi->mode & + (SPI_RX_DUAL | SPI_RX_QUAD | SPI_NO_RX)) > 1)) { dev_err(&spi->dev, - "setup: can not select dual and quad at the same time\n"); + "setup: can not select any two of dual, quad and no-rx/tx at the same time\n"); return -EINVAL; } - /* if it is SPI_3WIRE mode, DUAL and QUAD should be forbidden - */ + /* If it is SPI_3WIRE mode, DUAL and QUAD should be forbidden */ if ((spi->mode & SPI_3WIRE) && (spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL | SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL))) return -EINVAL; - /* help drivers fail *cleanly* when they need options - * that aren't supported with their current controller + /* Check against conflicting MOSI idle configuration */ + if ((spi->mode & SPI_MOSI_IDLE_LOW) && (spi->mode & SPI_MOSI_IDLE_HIGH)) { + dev_err(&spi->dev, + "setup: MOSI configured to idle low and high at the same time.\n"); + return -EINVAL; + } + /* + * Help drivers fail *cleanly* when they need options + * that aren't supported with their current controller. * SPI_CS_WORD has a fallback software implementation, * so it is ignored here. */ - bad_bits = spi->mode & ~(spi->controller->mode_bits | SPI_CS_WORD); + bad_bits = spi->mode & ~(spi->controller->mode_bits | SPI_CS_WORD | + SPI_NO_TX | SPI_NO_RX); ugly_bits = bad_bits & (SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL | SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL); @@ -2870,24 +3932,76 @@ int spi_setup(struct spi_device *spi) return -EINVAL; } - if (!spi->bits_per_word) + if (!spi->bits_per_word) { spi->bits_per_word = 8; + } else { + /* + * Some controllers may not support the default 8 bits-per-word + * so only perform the check when this is explicitly provided. + */ + status = __spi_validate_bits_per_word(spi->controller, + spi->bits_per_word); + if (status) + return status; + } - status = __spi_validate_bits_per_word(spi->controller, - spi->bits_per_word); - if (status) - return status; - - if (!spi->max_speed_hz) + if (spi->controller->max_speed_hz && + (!spi->max_speed_hz || + spi->max_speed_hz > spi->controller->max_speed_hz)) spi->max_speed_hz = spi->controller->max_speed_hz; - if (spi->controller->setup) + mutex_lock(&spi->controller->io_mutex); + + if (spi->controller->setup) { status = spi->controller->setup(spi); + if (status) { + mutex_unlock(&spi->controller->io_mutex); + dev_err(&spi->controller->dev, "Failed to setup device: %d\n", + status); + return status; + } + } - spi_set_cs(spi, false); + status = spi_set_cs_timing(spi); + if (status) { + mutex_unlock(&spi->controller->io_mutex); + return status; + } + + if (spi->controller->auto_runtime_pm && spi->controller->set_cs) { + status = pm_runtime_resume_and_get(spi->controller->dev.parent); + if (status < 0) { + mutex_unlock(&spi->controller->io_mutex); + dev_err(&spi->controller->dev, "Failed to power device: %d\n", + status); + return status; + } - dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n", - (int) (spi->mode & (SPI_CPOL | SPI_CPHA)), + /* + * We do not want to return positive value from pm_runtime_get, + * there are many instances of devices calling spi_setup() and + * checking for a non-zero return value instead of a negative + * return value. + */ + status = 0; + + spi_set_cs(spi, false, true); + pm_runtime_put_autosuspend(spi->controller->dev.parent); + } else { + spi_set_cs(spi, false, true); + } + + mutex_unlock(&spi->controller->io_mutex); + + if (spi->rt && !spi->controller->rt) { + spi->controller->rt = true; + spi_set_thread_rt(spi->controller); + } + + trace_spi_setup(spi, status); + + dev_dbg(&spi->dev, "setup mode %lu, %s%s%s%s%u bits/w, %u Hz max --> %d\n", + spi->mode & SPI_MODE_X_MASK, (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "", (spi->mode & SPI_LSB_FIRST) ? "lsb, " : "", (spi->mode & SPI_3WIRE) ? "3wire, " : "", @@ -2899,6 +4013,26 @@ int spi_setup(struct spi_device *spi) } EXPORT_SYMBOL_GPL(spi_setup); +static int _spi_xfer_word_delay_update(struct spi_transfer *xfer, + struct spi_device *spi) +{ + int delay1, delay2; + + delay1 = spi_delay_to_ns(&xfer->word_delay, xfer); + if (delay1 < 0) + return delay1; + + delay2 = spi_delay_to_ns(&spi->word_delay, xfer); + if (delay2 < 0) + return delay2; + + if (delay1 < delay2) + memcpy(&xfer->word_delay, &spi->word_delay, + sizeof(xfer->word_delay)); + + return 0; +} + static int __spi_validate(struct spi_device *spi, struct spi_message *message) { struct spi_controller *ctlr = spi->controller; @@ -2908,36 +4042,10 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message) if (list_empty(&message->transfers)) return -EINVAL; - /* If an SPI controller does not support toggling the CS line on each - * transfer (indicated by the SPI_CS_WORD flag) or we are using a GPIO - * for the CS line, we can emulate the CS-per-word hardware function by - * splitting transfers into one-word transfers and ensuring that - * cs_change is set for each transfer. - */ - if ((spi->mode & SPI_CS_WORD) && (!(ctlr->mode_bits & SPI_CS_WORD) || - gpio_is_valid(spi->cs_gpio))) { - size_t maxsize; - int ret; - - maxsize = (spi->bits_per_word + 7) / 8; - - /* spi_split_transfers_maxsize() requires message->spi */ - message->spi = spi; - - ret = spi_split_transfers_maxsize(ctlr, message, maxsize, - GFP_KERNEL); - if (ret) - return ret; - - list_for_each_entry(xfer, &message->transfers, transfer_list) { - /* don't change cs_change on the last entry in the list */ - if (list_is_last(&xfer->transfer_list, &message->transfers)) - break; - xfer->cs_change = 1; - } - } + message->spi = spi; - /* Half-duplex links include original MicroWire, and ones with + /* + * Half-duplex links include original MicroWire, and ones with * only one data pin like SPI_3WIRE (switches direction) or where * either MOSI or MISO is missing. They can also be caused by * software limitations. @@ -2956,22 +4064,23 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message) } } - /** + /* * Set transfer bits_per_word and max speed as spi device default if * it is not set for this transfer. * Set transfer tx_nbits and rx_nbits as single transfer default * (SPI_NBITS_SINGLE) if it is not set for this transfer. + * Ensure transfer word_delay is at least as long as that required by + * device itself. */ message->frame_length = 0; list_for_each_entry(xfer, &message->transfers, transfer_list) { + xfer->effective_speed_hz = 0; message->frame_length += xfer->len; if (!xfer->bits_per_word) xfer->bits_per_word = spi->bits_per_word; if (!xfer->speed_hz) xfer->speed_hz = spi->max_speed_hz; - if (!xfer->speed_hz) - xfer->speed_hz = ctlr->max_speed_hz; if (ctlr->max_speed_hz && xfer->speed_hz > ctlr->max_speed_hz) xfer->speed_hz = ctlr->max_speed_hz; @@ -2979,9 +4088,16 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message) if (__spi_validate_bits_per_word(ctlr, xfer->bits_per_word)) return -EINVAL; + /* DDR mode is supported only if controller has dtr_caps=true. + * default considered as SDR mode for SPI and QSPI controller. + * Note: This is applicable only to QSPI controller. + */ + if (xfer->dtr_mode && !ctlr->dtr_caps) + return -EINVAL; + /* * SPI transfer length should be multiple of SPI word size - * where SPI word size should be power-of-two multiple + * where SPI word size should be power-of-two multiple. */ if (xfer->bits_per_word <= 8) w_size = 1; @@ -3002,33 +4118,58 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message) xfer->tx_nbits = SPI_NBITS_SINGLE; if (xfer->rx_buf && !xfer->rx_nbits) xfer->rx_nbits = SPI_NBITS_SINGLE; - /* check transfer tx/rx_nbits: + /* + * Check transfer tx/rx_nbits: * 1. check the value matches one of single, dual and quad * 2. check tx/rx_nbits match the mode in spi_device */ if (xfer->tx_buf) { + if (spi->mode & SPI_NO_TX) + return -EINVAL; if (xfer->tx_nbits != SPI_NBITS_SINGLE && xfer->tx_nbits != SPI_NBITS_DUAL && - xfer->tx_nbits != SPI_NBITS_QUAD) + xfer->tx_nbits != SPI_NBITS_QUAD && + xfer->tx_nbits != SPI_NBITS_OCTAL) return -EINVAL; if ((xfer->tx_nbits == SPI_NBITS_DUAL) && - !(spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD))) + !(spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL))) return -EINVAL; if ((xfer->tx_nbits == SPI_NBITS_QUAD) && - !(spi->mode & SPI_TX_QUAD)) + !(spi->mode & (SPI_TX_QUAD | SPI_TX_OCTAL))) + return -EINVAL; + if ((xfer->tx_nbits == SPI_NBITS_OCTAL) && + !(spi->mode & SPI_TX_OCTAL)) return -EINVAL; } - /* check transfer rx_nbits */ + /* Check transfer rx_nbits */ if (xfer->rx_buf) { + if (spi->mode & SPI_NO_RX) + return -EINVAL; if (xfer->rx_nbits != SPI_NBITS_SINGLE && xfer->rx_nbits != SPI_NBITS_DUAL && - xfer->rx_nbits != SPI_NBITS_QUAD) + xfer->rx_nbits != SPI_NBITS_QUAD && + xfer->rx_nbits != SPI_NBITS_OCTAL) return -EINVAL; if ((xfer->rx_nbits == SPI_NBITS_DUAL) && - !(spi->mode & (SPI_RX_DUAL | SPI_RX_QUAD))) + !(spi->mode & (SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL))) return -EINVAL; if ((xfer->rx_nbits == SPI_NBITS_QUAD) && - !(spi->mode & SPI_RX_QUAD)) + !(spi->mode & (SPI_RX_QUAD | SPI_RX_OCTAL))) + return -EINVAL; + if ((xfer->rx_nbits == SPI_NBITS_OCTAL) && + !(spi->mode & SPI_RX_OCTAL)) + return -EINVAL; + } + + if (_spi_xfer_word_delay_update(xfer, spi)) + return -EINVAL; + + /* Make sure controller supports required offload features. */ + if (xfer->offload_flags) { + if (!message->offload) + return -EINVAL; + + if (xfer->offload_flags & ~message->offload->xfer_flags) return -EINVAL; } } @@ -3038,9 +4179,186 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message) return 0; } +/* + * spi_split_transfers - generic handling of transfer splitting + * @msg: the message to split + * + * Under certain conditions, a SPI controller may not support arbitrary + * transfer sizes or other features required by a peripheral. This function + * will split the transfers in the message into smaller transfers that are + * supported by the controller. + * + * Controllers with special requirements not covered here can also split + * transfers in the optimize_message() callback. + * + * Context: can sleep + * Return: zero on success, else a negative error code + */ +static int spi_split_transfers(struct spi_message *msg) +{ + struct spi_controller *ctlr = msg->spi->controller; + struct spi_transfer *xfer; + int ret; + + /* + * If an SPI controller does not support toggling the CS line on each + * transfer (indicated by the SPI_CS_WORD flag) or we are using a GPIO + * for the CS line, we can emulate the CS-per-word hardware function by + * splitting transfers into one-word transfers and ensuring that + * cs_change is set for each transfer. + */ + if ((msg->spi->mode & SPI_CS_WORD) && + (!(ctlr->mode_bits & SPI_CS_WORD) || spi_is_csgpiod(msg->spi))) { + ret = spi_split_transfers_maxwords(ctlr, msg, 1); + if (ret) + return ret; + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + /* Don't change cs_change on the last entry in the list */ + if (list_is_last(&xfer->transfer_list, &msg->transfers)) + break; + + xfer->cs_change = 1; + } + } else { + ret = spi_split_transfers_maxsize(ctlr, msg, + spi_max_transfer_size(msg->spi)); + if (ret) + return ret; + } + + return 0; +} + +/* + * __spi_optimize_message - shared implementation for spi_optimize_message() + * and spi_maybe_optimize_message() + * @spi: the device that will be used for the message + * @msg: the message to optimize + * + * Peripheral drivers will call spi_optimize_message() and the spi core will + * call spi_maybe_optimize_message() instead of calling this directly. + * + * It is not valid to call this on a message that has already been optimized. + * + * Return: zero on success, else a negative error code + */ +static int __spi_optimize_message(struct spi_device *spi, + struct spi_message *msg) +{ + struct spi_controller *ctlr = spi->controller; + int ret; + + ret = __spi_validate(spi, msg); + if (ret) + return ret; + + ret = spi_split_transfers(msg); + if (ret) + return ret; + + if (ctlr->optimize_message) { + ret = ctlr->optimize_message(msg); + if (ret) { + spi_res_release(ctlr, msg); + return ret; + } + } + + msg->optimized = true; + + return 0; +} + +/* + * spi_maybe_optimize_message - optimize message if it isn't already pre-optimized + * @spi: the device that will be used for the message + * @msg: the message to optimize + * Return: zero on success, else a negative error code + */ +static int spi_maybe_optimize_message(struct spi_device *spi, + struct spi_message *msg) +{ + if (spi->controller->defer_optimize_message) { + msg->spi = spi; + return 0; + } + + if (msg->pre_optimized) + return 0; + + return __spi_optimize_message(spi, msg); +} + +/** + * spi_optimize_message - do any one-time validation and setup for a SPI message + * @spi: the device that will be used for the message + * @msg: the message to optimize + * + * Peripheral drivers that reuse the same message repeatedly may call this to + * perform as much message prep as possible once, rather than repeating it each + * time a message transfer is performed to improve throughput and reduce CPU + * usage. + * + * Once a message has been optimized, it cannot be modified with the exception + * of updating the contents of any xfer->tx_buf (the pointer can't be changed, + * only the data in the memory it points to). + * + * Calls to this function must be balanced with calls to spi_unoptimize_message() + * to avoid leaking resources. + * + * Context: can sleep + * Return: zero on success, else a negative error code + */ +int spi_optimize_message(struct spi_device *spi, struct spi_message *msg) +{ + int ret; + + /* + * Pre-optimization is not supported and optimization is deferred e.g. + * when using spi-mux. + */ + if (spi->controller->defer_optimize_message) + return 0; + + ret = __spi_optimize_message(spi, msg); + if (ret) + return ret; + + /* + * This flag indicates that the peripheral driver called spi_optimize_message() + * and therefore we shouldn't unoptimize message automatically when finalizing + * the message but rather wait until spi_unoptimize_message() is called + * by the peripheral driver. + */ + msg->pre_optimized = true; + + return 0; +} +EXPORT_SYMBOL_GPL(spi_optimize_message); + +/** + * spi_unoptimize_message - releases any resources allocated by spi_optimize_message() + * @msg: the message to unoptimize + * + * Calls to this function must be balanced with calls to spi_optimize_message(). + * + * Context: can sleep + */ +void spi_unoptimize_message(struct spi_message *msg) +{ + if (msg->spi->controller->defer_optimize_message) + return; + + __spi_unoptimize_message(msg); + msg->pre_optimized = false; +} +EXPORT_SYMBOL_GPL(spi_unoptimize_message); + static int __spi_async(struct spi_device *spi, struct spi_message *message) { struct spi_controller *ctlr = spi->controller; + struct spi_transfer *xfer; /* * Some controllers do not support doing regular SPI transfers. Return @@ -3049,21 +4367,54 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message) if (!ctlr->transfer) return -ENOTSUPP; - message->spi = spi; - - SPI_STATISTICS_INCREMENT_FIELD(&ctlr->statistics, spi_async); - SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_async); + SPI_STATISTICS_INCREMENT_FIELD(ctlr->pcpu_statistics, spi_async); + SPI_STATISTICS_INCREMENT_FIELD(spi->pcpu_statistics, spi_async); trace_spi_message_submit(message); + if (!ctlr->ptp_sts_supported) { + list_for_each_entry(xfer, &message->transfers, transfer_list) { + xfer->ptp_sts_word_pre = 0; + ptp_read_system_prets(xfer->ptp_sts); + } + } + return ctlr->transfer(spi, message); } +static void devm_spi_unoptimize_message(void *msg) +{ + spi_unoptimize_message(msg); +} + +/** + * devm_spi_optimize_message - managed version of spi_optimize_message() + * @dev: the device that manages @msg (usually @spi->dev) + * @spi: the device that will be used for the message + * @msg: the message to optimize + * Return: zero on success, else a negative error code + * + * spi_unoptimize_message() will automatically be called when the device is + * removed. + */ +int devm_spi_optimize_message(struct device *dev, struct spi_device *spi, + struct spi_message *msg) +{ + int ret; + + ret = spi_optimize_message(spi, msg); + if (ret) + return ret; + + return devm_add_action_or_reset(dev, devm_spi_unoptimize_message, msg); +} +EXPORT_SYMBOL_GPL(devm_spi_optimize_message); + /** * spi_async - asynchronous SPI transfer * @spi: device with which data will be exchanged * @message: describes the data transfers, including completion callback - * Context: any (irqs may be blocked, etc) + * Context: any (IRQs may be blocked, etc) * * This call may be used in_irq and other contexts which can't sleep, * as well as from task contexts which can sleep. @@ -3096,8 +4447,8 @@ int spi_async(struct spi_device *spi, struct spi_message *message) int ret; unsigned long flags; - ret = __spi_validate(spi, message); - if (ret != 0) + ret = spi_maybe_optimize_message(spi, message); + if (ret) return ret; spin_lock_irqsave(&ctlr->bus_lock_spinlock, flags); @@ -3113,61 +4464,41 @@ int spi_async(struct spi_device *spi, struct spi_message *message) } EXPORT_SYMBOL_GPL(spi_async); -/** - * spi_async_locked - version of spi_async with exclusive bus usage - * @spi: device with which data will be exchanged - * @message: describes the data transfers, including completion callback - * Context: any (irqs may be blocked, etc) - * - * This call may be used in_irq and other contexts which can't sleep, - * as well as from task contexts which can sleep. - * - * The completion callback is invoked in a context which can't sleep. - * Before that invocation, the value of message->status is undefined. - * When the callback is issued, message->status holds either zero (to - * indicate complete success) or a negative error code. After that - * callback returns, the driver which issued the transfer request may - * deallocate the associated memory; it's no longer in use by any SPI - * core or controller driver code. - * - * Note that although all messages to a spi_device are handled in - * FIFO order, messages may go to different devices in other orders. - * Some device might be higher priority, or have various "hard" access - * time requirements, for example. - * - * On detection of any fault during the transfer, processing of - * the entire message is aborted, and the device is deselected. - * Until returning from the associated message completion callback, - * no other spi_message queued to that device will be processed. - * (This rule applies equally to all the synchronous transfer calls, - * which are wrappers around this core asynchronous primitive.) - * - * Return: zero on success, else a negative error code. - */ -int spi_async_locked(struct spi_device *spi, struct spi_message *message) +static void __spi_transfer_message_noqueue(struct spi_controller *ctlr, struct spi_message *msg) { - struct spi_controller *ctlr = spi->controller; + bool was_busy; int ret; - unsigned long flags; - - ret = __spi_validate(spi, message); - if (ret != 0) - return ret; - spin_lock_irqsave(&ctlr->bus_lock_spinlock, flags); + mutex_lock(&ctlr->io_mutex); - ret = __spi_async(spi, message); + was_busy = ctlr->busy; - spin_unlock_irqrestore(&ctlr->bus_lock_spinlock, flags); + ctlr->cur_msg = msg; + ret = __spi_pump_transfer_message(ctlr, msg, was_busy); + if (ret) + dev_err(&ctlr->dev, "noqueue transfer failed\n"); + ctlr->cur_msg = NULL; + ctlr->fallback = false; - return ret; + if (!was_busy) { + kfree(ctlr->dummy_rx); + ctlr->dummy_rx = NULL; + kfree(ctlr->dummy_tx); + ctlr->dummy_tx = NULL; + if (ctlr->unprepare_transfer_hardware && + ctlr->unprepare_transfer_hardware(ctlr)) + dev_err(&ctlr->dev, + "failed to unprepare transfer hardware\n"); + spi_idle_runtime_pm(ctlr); + } + mutex_unlock(&ctlr->io_mutex); } -EXPORT_SYMBOL_GPL(spi_async_locked); /*-------------------------------------------------------------------------*/ -/* Utility methods for SPI protocol drivers, layered on +/* + * Utility methods for SPI protocol drivers, layered on * top of the core. Some other utility methods are defined as * inline functions. */ @@ -3180,54 +4511,62 @@ static void spi_complete(void *arg) static int __spi_sync(struct spi_device *spi, struct spi_message *message) { DECLARE_COMPLETION_ONSTACK(done); + unsigned long flags; int status; struct spi_controller *ctlr = spi->controller; - unsigned long flags; - status = __spi_validate(spi, message); - if (status != 0) - return status; + if (__spi_check_suspended(ctlr)) { + dev_warn_once(&spi->dev, "Attempted to sync while suspend\n"); + return -ESHUTDOWN; + } - message->complete = spi_complete; - message->context = &done; - message->spi = spi; + status = spi_maybe_optimize_message(spi, message); + if (status) + return status; - SPI_STATISTICS_INCREMENT_FIELD(&ctlr->statistics, spi_sync); - SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_sync); + SPI_STATISTICS_INCREMENT_FIELD(ctlr->pcpu_statistics, spi_sync); + SPI_STATISTICS_INCREMENT_FIELD(spi->pcpu_statistics, spi_sync); - /* If we're not using the legacy transfer method then we will - * try to transfer in the calling context so special case. - * This code would be less tricky if we could remove the - * support for driver implemented message queues. + /* + * Checking queue_empty here only guarantees async/sync message + * ordering when coming from the same context. It does not need to + * guard against reentrancy from a different context. The io_mutex + * will catch those cases. */ - if (ctlr->transfer == spi_queued_transfer) { - spin_lock_irqsave(&ctlr->bus_lock_spinlock, flags); + if (READ_ONCE(ctlr->queue_empty) && !ctlr->must_async) { + message->actual_length = 0; + message->status = -EINPROGRESS; trace_spi_message_submit(message); - status = __spi_queued_transfer(spi, message, false); + SPI_STATISTICS_INCREMENT_FIELD(ctlr->pcpu_statistics, spi_sync_immediate); + SPI_STATISTICS_INCREMENT_FIELD(spi->pcpu_statistics, spi_sync_immediate); - spin_unlock_irqrestore(&ctlr->bus_lock_spinlock, flags); - } else { - status = spi_async_locked(spi, message); + __spi_transfer_message_noqueue(ctlr, message); + + return message->status; } - if (status == 0) { - /* Push out the messages in the calling context if we - * can. - */ - if (ctlr->transfer == spi_queued_transfer) { - SPI_STATISTICS_INCREMENT_FIELD(&ctlr->statistics, - spi_sync_immediate); - SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, - spi_sync_immediate); - __spi_pump_messages(ctlr, false); - } + /* + * There are messages in the async queue that could have originated + * from the same context, so we need to preserve ordering. + * Therefor we send the message to the async queue and wait until they + * are completed. + */ + message->complete = spi_complete; + message->context = &done; + + spin_lock_irqsave(&ctlr->bus_lock_spinlock, flags); + status = __spi_async(spi, message); + spin_unlock_irqrestore(&ctlr->bus_lock_spinlock, flags); + if (status == 0) { wait_for_completion(&done); status = message->status; } + message->complete = NULL; message->context = NULL; + return status; } @@ -3288,7 +4627,7 @@ EXPORT_SYMBOL_GPL(spi_sync_locked); /** * spi_bus_lock - obtain a lock for exclusive SPI bus usage - * @ctlr: SPI bus master that should be locked for exclusive bus access + * @ctlr: SPI bus controller that should be locked for exclusive bus access * Context: can sleep * * This call may only be used from a context that may sleep. The sleep @@ -3311,7 +4650,7 @@ int spi_bus_lock(struct spi_controller *ctlr) ctlr->bus_lock_flag = 1; spin_unlock_irqrestore(&ctlr->bus_lock_spinlock, flags); - /* mutex remains locked until spi_bus_unlock is called */ + /* Mutex remains locked until spi_bus_unlock() is called */ return 0; } @@ -3319,7 +4658,7 @@ EXPORT_SYMBOL_GPL(spi_bus_lock); /** * spi_bus_unlock - release the lock for exclusive SPI bus usage - * @ctlr: SPI bus master that was locked for exclusive bus access + * @ctlr: SPI bus controller that was locked for exclusive bus access * Context: can sleep * * This call may only be used from a context that may sleep. The sleep @@ -3340,7 +4679,7 @@ int spi_bus_unlock(struct spi_controller *ctlr) } EXPORT_SYMBOL_GPL(spi_bus_unlock); -/* portable code must never pass more than 32 bytes */ +/* Portable code must never pass more than 32 bytes */ #define SPI_BUFSIZ max(32, SMP_CACHE_BYTES) static u8 *buf; @@ -3348,9 +4687,9 @@ static u8 *buf; /** * spi_write_then_read - SPI synchronous write followed by read * @spi: device with which data will be exchanged - * @txbuf: data to be written (need not be dma-safe) + * @txbuf: data to be written (need not be DMA-safe) * @n_tx: size of txbuf, in bytes - * @rxbuf: buffer into which data will be read (need not be dma-safe) + * @rxbuf: buffer into which data will be read (need not be DMA-safe) * @n_rx: size of rxbuf, in bytes * Context: can sleep * @@ -3359,10 +4698,9 @@ static u8 *buf; * is zero for success, else a negative errno status code. * This call may only be used from a context that may sleep. * - * Parameters to this routine are always copied using a small buffer; - * portable code should never use this for more than 32 bytes. + * Parameters to this routine are always copied using a small buffer. * Performance-sensitive or bulk transfer code should instead use - * spi_{async,sync}() calls with dma-safe buffers. + * spi_{async,sync}() calls with DMA-safe buffers. * * Return: zero on success, else a negative error code. */ @@ -3377,7 +4715,8 @@ int spi_write_then_read(struct spi_device *spi, struct spi_transfer x[2]; u8 *local_buf; - /* Use preallocated DMA-safe buffer if we can. We can't avoid + /* + * Use preallocated DMA-safe buffer if we can. We can't avoid * copying here, (as a pure convenience thing), but we can * keep heap costs out of the hot path unless someone else is * using the pre-allocated buffer or the transfer is too large. @@ -3406,7 +4745,7 @@ int spi_write_then_read(struct spi_device *spi, x[0].tx_buf = local_buf; x[1].rx_buf = local_buf + n_tx; - /* do the i/o */ + /* Do the I/O */ status = spi_sync(spi, &message); if (status == 0) memcpy(rxbuf, x[1].rx_buf, n_rx); @@ -3422,42 +4761,27 @@ EXPORT_SYMBOL_GPL(spi_write_then_read); /*-------------------------------------------------------------------------*/ -#if IS_ENABLED(CONFIG_OF) -static int __spi_of_device_match(struct device *dev, void *data) +#if IS_ENABLED(CONFIG_OF_DYNAMIC) +/* Must call put_device() when done with returned spi_device device */ +static struct spi_device *of_find_spi_device_by_node(struct device_node *node) { - return dev->of_node == data; -} + struct device *dev = bus_find_device_by_of_node(&spi_bus_type, node); -/* must call put_device() when done with returned spi_device device */ -struct spi_device *of_find_spi_device_by_node(struct device_node *node) -{ - struct device *dev = bus_find_device(&spi_bus_type, NULL, node, - __spi_of_device_match); return dev ? to_spi_device(dev) : NULL; } -EXPORT_SYMBOL_GPL(of_find_spi_device_by_node); -#endif /* IS_ENABLED(CONFIG_OF) */ -#if IS_ENABLED(CONFIG_OF_DYNAMIC) -static int __spi_of_controller_match(struct device *dev, const void *data) -{ - return dev->of_node == data; -} - -/* the spi controllers are not using spi_bus, so we find it with another way */ +/* The spi controllers are not using spi_bus, so we find it with another way */ static struct spi_controller *of_find_spi_controller_by_node(struct device_node *node) { struct device *dev; - dev = class_find_device(&spi_master_class, NULL, node, - __spi_of_controller_match); + dev = class_find_device_by_of_node(&spi_controller_class, node); if (!dev && IS_ENABLED(CONFIG_SPI_SLAVE)) - dev = class_find_device(&spi_slave_class, NULL, node, - __spi_of_controller_match); + dev = class_find_device_by_of_node(&spi_target_class, node); if (!dev) return NULL; - /* reference got in class_find_device */ + /* Reference got in class_find_device */ return container_of(dev, struct spi_controller, dev); } @@ -3472,13 +4796,18 @@ static int of_spi_notify(struct notifier_block *nb, unsigned long action, case OF_RECONFIG_CHANGE_ADD: ctlr = of_find_spi_controller_by_node(rd->dn->parent); if (ctlr == NULL) - return NOTIFY_OK; /* not for us */ + return NOTIFY_OK; /* Not for us */ if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) { put_device(&ctlr->dev); return NOTIFY_OK; } + /* + * Clear the flag before adding the device so that fw_devlink + * doesn't skip adding consumers to this device. + */ + rd->dn->fwnode.flags &= ~FWNODE_FLAG_NOT_DEVICE; spi = of_register_spi_device(ctlr, rd->dn); put_device(&ctlr->dev); @@ -3491,19 +4820,19 @@ static int of_spi_notify(struct notifier_block *nb, unsigned long action, break; case OF_RECONFIG_CHANGE_REMOVE: - /* already depopulated? */ + /* Already depopulated? */ if (!of_node_check_flag(rd->dn, OF_POPULATED)) return NOTIFY_OK; - /* find our device by node */ + /* Find our device by node */ spi = of_find_spi_device_by_node(rd->dn); if (spi == NULL) - return NOTIFY_OK; /* no? not meant for us */ + return NOTIFY_OK; /* No? not meant for us */ - /* unregister takes one ref away */ + /* Unregister takes one ref away */ spi_unregister_device(spi); - /* and put the reference of the find */ + /* And put the reference of the find */ put_device(&spi->dev); break; } @@ -3521,36 +4850,31 @@ extern struct notifier_block spi_of_notifier; #if IS_ENABLED(CONFIG_ACPI) static int spi_acpi_controller_match(struct device *dev, const void *data) { - return ACPI_COMPANION(dev->parent) == data; -} - -static int spi_acpi_device_match(struct device *dev, void *data) -{ - return ACPI_COMPANION(dev) == data; + return device_match_acpi_dev(dev->parent, data); } -static struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_device *adev) +struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_device *adev) { struct device *dev; - dev = class_find_device(&spi_master_class, NULL, adev, + dev = class_find_device(&spi_controller_class, NULL, adev, spi_acpi_controller_match); if (!dev && IS_ENABLED(CONFIG_SPI_SLAVE)) - dev = class_find_device(&spi_slave_class, NULL, adev, + dev = class_find_device(&spi_target_class, NULL, adev, spi_acpi_controller_match); if (!dev) return NULL; return container_of(dev, struct spi_controller, dev); } +EXPORT_SYMBOL_GPL(acpi_spi_find_controller_by_adev); static struct spi_device *acpi_spi_find_device_by_adev(struct acpi_device *adev) { struct device *dev; - dev = bus_find_device(&spi_bus_type, NULL, adev, spi_acpi_device_match); - - return dev ? to_spi_device(dev) : NULL; + dev = bus_find_device_by_acpi_dev(&spi_bus_type, adev); + return to_spi_device(dev); } static int acpi_spi_notify(struct notifier_block *nb, unsigned long value, @@ -3562,7 +4886,7 @@ static int acpi_spi_notify(struct notifier_block *nb, unsigned long value, switch (value) { case ACPI_RECONFIG_DEVICE_ADD: - ctlr = acpi_spi_find_controller_by_adev(adev->parent); + ctlr = acpi_spi_find_controller_by_adev(acpi_dev_parent(adev)); if (!ctlr) break; @@ -3606,12 +4930,12 @@ static int __init spi_init(void) if (status < 0) goto err1; - status = class_register(&spi_master_class); + status = class_register(&spi_controller_class); if (status < 0) goto err2; if (IS_ENABLED(CONFIG_SPI_SLAVE)) { - status = class_register(&spi_slave_class); + status = class_register(&spi_target_class); if (status < 0) goto err3; } @@ -3624,7 +4948,7 @@ static int __init spi_init(void) return 0; err3: - class_unregister(&spi_master_class); + class_unregister(&spi_controller_class); err2: bus_unregister(&spi_bus_type); err1: @@ -3634,12 +4958,12 @@ err0: return status; } -/* board_info is normally registered in arch_initcall(), - * but even essential drivers wait till later +/* + * A board_info is normally registered in arch_initcall(), + * but even essential drivers wait till later. * - * REVISIT only boardinfo really needs static linking. the rest (device and - * driver registration) _could_ be dynamically linked (modular) ... costs + * REVISIT only boardinfo really needs static linking. The rest (device and + * driver registration) _could_ be dynamically linked (modular) ... Costs * include needing to have boardinfo data structures be much more public. */ postcore_initcall(spi_init); - |