diff options
Diffstat (limited to 'drivers/spi/spi.c')
| -rw-r--r-- | drivers/spi/spi.c | 90 |
1 files changed, 80 insertions, 10 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 47eff8012a77..b30f03a99dfd 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -702,6 +702,7 @@ static int spi_map_buf(struct spi_master *master, struct device *dev, enum dma_data_direction dir) { const bool vmalloced_buf = is_vmalloc_addr(buf); + unsigned int max_seg_size = dma_get_max_seg_size(dev); int desc_len; int sgs; struct page *vm_page; @@ -710,10 +711,10 @@ static int spi_map_buf(struct spi_master *master, struct device *dev, int i, ret; if (vmalloced_buf) { - desc_len = PAGE_SIZE; + desc_len = min_t(int, max_seg_size, PAGE_SIZE); sgs = DIV_ROUND_UP(len + offset_in_page(buf), desc_len); } else { - desc_len = master->max_dma_len; + desc_len = min_t(int, max_seg_size, master->max_dma_len); sgs = DIV_ROUND_UP(len, desc_len); } @@ -739,7 +740,6 @@ static int spi_map_buf(struct spi_master *master, struct device *dev, sg_set_buf(&sgt->sgl[i], sg_buf, min); } - buf += min; len -= min; } @@ -1047,6 +1047,7 @@ EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); * __spi_pump_messages - function which processes spi message queue * @master: master to process queue for * @in_kthread: true if we are in the context of the message pump thread + * @bus_locked: true if the bus mutex is held when calling this function * * 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 @@ -1056,7 +1057,8 @@ EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); * inside spi_sync(); the queue extraction handling at the top of the * function should deal with this safely. */ -static void __spi_pump_messages(struct spi_master *master, bool in_kthread) +static void __spi_pump_messages(struct spi_master *master, bool in_kthread, + bool bus_locked) { unsigned long flags; bool was_busy = false; @@ -1152,6 +1154,9 @@ static void __spi_pump_messages(struct spi_master *master, bool in_kthread) } } + if (!bus_locked) + mutex_lock(&master->bus_lock_mutex); + trace_spi_message_start(master->cur_msg); if (master->prepare_message) { @@ -1161,7 +1166,7 @@ static void __spi_pump_messages(struct spi_master *master, bool in_kthread) "failed to prepare message: %d\n", ret); master->cur_msg->status = ret; spi_finalize_current_message(master); - return; + goto out; } master->cur_msg_prepared = true; } @@ -1170,15 +1175,23 @@ static void __spi_pump_messages(struct spi_master *master, bool in_kthread) if (ret) { master->cur_msg->status = ret; spi_finalize_current_message(master); - return; + goto out; } ret = master->transfer_one_message(master, master->cur_msg); if (ret) { dev_err(&master->dev, "failed to transfer one message from queue\n"); - return; + goto out; } + +out: + if (!bus_locked) + mutex_unlock(&master->bus_lock_mutex); + + /* Prod the scheduler in case transfer_one() was busy waiting */ + if (!ret) + cond_resched(); } /** @@ -1190,7 +1203,7 @@ static void spi_pump_messages(struct kthread_work *work) struct spi_master *master = container_of(work, struct spi_master, pump_messages); - __spi_pump_messages(master, true); + __spi_pump_messages(master, true, false); } static int spi_init_queue(struct spi_master *master) @@ -1581,13 +1594,30 @@ static void of_register_spi_devices(struct spi_master *master) { } static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) { struct spi_device *spi = data; + struct spi_master *master = spi->master; if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { struct acpi_resource_spi_serialbus *sb; sb = &ares->data.spi_serial_bus; if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_SPI) { - spi->chip_select = sb->device_selection; + /* + * ACPI DeviceSelection numbering is handled by the + * host controller driver in Windows and can vary + * from driver to driver. In Linux we always expect + * 0 .. max - 1 so we need to ask the driver to + * translate between the two schemes. + */ + if (master->fw_translate_cs) { + int cs = master->fw_translate_cs(master, + sb->device_selection); + if (cs < 0) + return cs; + spi->chip_select = cs; + } else { + spi->chip_select = sb->device_selection; + } + spi->max_speed_hz = sb->connection_speed; if (sb->clock_phase == ACPI_SPI_SECOND_PHASE) @@ -2351,6 +2381,46 @@ int spi_async_locked(struct spi_device *spi, struct spi_message *message) EXPORT_SYMBOL_GPL(spi_async_locked); +int spi_flash_read(struct spi_device *spi, + struct spi_flash_read_message *msg) + +{ + struct spi_master *master = spi->master; + int ret; + + if ((msg->opcode_nbits == SPI_NBITS_DUAL || + msg->addr_nbits == SPI_NBITS_DUAL) && + !(spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD))) + return -EINVAL; + if ((msg->opcode_nbits == SPI_NBITS_QUAD || + msg->addr_nbits == SPI_NBITS_QUAD) && + !(spi->mode & SPI_TX_QUAD)) + return -EINVAL; + if (msg->data_nbits == SPI_NBITS_DUAL && + !(spi->mode & (SPI_RX_DUAL | SPI_RX_QUAD))) + return -EINVAL; + if (msg->data_nbits == SPI_NBITS_QUAD && + !(spi->mode & SPI_RX_QUAD)) + return -EINVAL; + + if (master->auto_runtime_pm) { + ret = pm_runtime_get_sync(master->dev.parent); + if (ret < 0) { + dev_err(&master->dev, "Failed to power device: %d\n", + ret); + return ret; + } + } + mutex_lock(&master->bus_lock_mutex); + ret = master->spi_flash_read(spi, msg); + mutex_unlock(&master->bus_lock_mutex); + if (master->auto_runtime_pm) + pm_runtime_put(master->dev.parent); + + return ret; +} +EXPORT_SYMBOL_GPL(spi_flash_read); + /*-------------------------------------------------------------------------*/ /* Utility methods for SPI master protocol drivers, layered on @@ -2414,7 +2484,7 @@ static int __spi_sync(struct spi_device *spi, struct spi_message *message, spi_sync_immediate); SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_sync_immediate); - __spi_pump_messages(master, false); + __spi_pump_messages(master, false, bus_locked); } wait_for_completion(&done); |