diff options
Diffstat (limited to 'drivers/misc/eeprom/eeprom_93xx46.c')
| -rw-r--r-- | drivers/misc/eeprom/eeprom_93xx46.c | 345 |
1 files changed, 188 insertions, 157 deletions
diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c index 94cc035aa841..9cae6f530679 100644 --- a/drivers/misc/eeprom/eeprom_93xx46.c +++ b/drivers/misc/eeprom/eeprom_93xx46.c @@ -1,26 +1,46 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Driver for 93xx46 EEPROMs * * (C) 2011 DENX Software Engineering, Anatolij Gustschin <agust@denx.de> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. */ +#include <linux/array_size.h> +#include <linux/bits.h> #include <linux/delay.h> #include <linux/device.h> #include <linux/gpio/consumer.h> -#include <linux/kernel.h> +#include <linux/kstrtox.h> +#include <linux/log2.h> +#include <linux/mod_devicetable.h> #include <linux/module.h> #include <linux/mutex.h> -#include <linux/of.h> -#include <linux/of_device.h> -#include <linux/of_gpio.h> +#include <linux/property.h> #include <linux/slab.h> #include <linux/spi/spi.h> +#include <linux/string_choices.h> + #include <linux/nvmem-provider.h> -#include <linux/eeprom_93xx46.h> + +struct eeprom_93xx46_platform_data { + unsigned char flags; +#define EE_ADDR8 0x01 /* 8 bit addr. cfg */ +#define EE_ADDR16 0x02 /* 16 bit addr. cfg */ +#define EE_READONLY 0x08 /* forbid writing */ +#define EE_SIZE1K 0x10 /* 1 kb of data, that is a 93xx46 */ +#define EE_SIZE2K 0x20 /* 2 kb of data, that is a 93xx56 */ +#define EE_SIZE4K 0x40 /* 4 kb of data, that is a 93xx66 */ + + unsigned int quirks; +/* Single word read transfers only; no sequential read. */ +#define EEPROM_93XX46_QUIRK_SINGLE_WORD_READ (1 << 0) +/* Instructions such as EWEN are (addrlen + 2) in length. */ +#define EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH (1 << 1) +/* Add extra cycle after address during a read */ +#define EEPROM_93XX46_QUIRK_EXTRA_READ_CYCLE BIT(2) + + struct gpio_desc *select; +}; #define OP_START 0x4 #define OP_WRITE (OP_START | 0x1) @@ -31,13 +51,32 @@ struct eeprom_93xx46_devtype_data { unsigned int quirks; + unsigned char flags; +}; + +static const struct eeprom_93xx46_devtype_data at93c46_data = { + .flags = EE_SIZE1K, +}; + +static const struct eeprom_93xx46_devtype_data at93c56_data = { + .flags = EE_SIZE2K, +}; + +static const struct eeprom_93xx46_devtype_data at93c66_data = { + .flags = EE_SIZE4K, }; static const struct eeprom_93xx46_devtype_data atmel_at93c46d_data = { + .flags = EE_SIZE1K, .quirks = EEPROM_93XX46_QUIRK_SINGLE_WORD_READ | EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH, }; +static const struct eeprom_93xx46_devtype_data microchip_93lc46b_data = { + .flags = EE_SIZE1K, + .quirks = EEPROM_93XX46_QUIRK_EXTRA_READ_CYCLE, +}; + struct eeprom_93xx46_dev { struct spi_device *spi; struct eeprom_93xx46_platform_data *pdata; @@ -58,12 +97,18 @@ static inline bool has_quirk_instruction_length(struct eeprom_93xx46_dev *edev) return edev->pdata->quirks & EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH; } +static inline bool has_quirk_extra_read_cycle(struct eeprom_93xx46_dev *edev) +{ + return edev->pdata->quirks & EEPROM_93XX46_QUIRK_EXTRA_READ_CYCLE; +} + static int eeprom_93xx46_read(void *priv, unsigned int off, void *val, size_t count) { struct eeprom_93xx46_dev *edev = priv; char *buf = val; int err = 0; + int bits; if (unlikely(off >= edev->size)) return 0; @@ -74,24 +119,23 @@ static int eeprom_93xx46_read(void *priv, unsigned int off, mutex_lock(&edev->lock); - if (edev->pdata->prepare) - edev->pdata->prepare(edev); + gpiod_set_value_cansleep(edev->pdata->select, 1); + + /* The opcode in front of the address is three bits. */ + bits = edev->addrlen + 3; while (count) { struct spi_message m; - struct spi_transfer t[2] = { { 0 } }; + struct spi_transfer t[2] = {}; u16 cmd_addr = OP_READ << edev->addrlen; size_t nbytes = count; - int bits; - if (edev->addrlen == 7) { - cmd_addr |= off & 0x7f; - bits = 10; + if (edev->pdata->flags & EE_ADDR8) { + cmd_addr |= off; if (has_quirk_single_word_read(edev)) nbytes = 1; } else { - cmd_addr |= (off >> 1) & 0x3f; - bits = 9; + cmd_addr |= (off >> 1); if (has_quirk_single_word_read(edev)) nbytes = 2; } @@ -99,25 +143,28 @@ static int eeprom_93xx46_read(void *priv, unsigned int off, dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n", cmd_addr, edev->spi->max_speed_hz); - spi_message_init(&m); + if (has_quirk_extra_read_cycle(edev)) { + cmd_addr <<= 1; + bits += 1; + } t[0].tx_buf = (char *)&cmd_addr; t[0].len = 2; t[0].bits_per_word = bits; - spi_message_add_tail(&t[0], &m); t[1].rx_buf = buf; t[1].len = count; t[1].bits_per_word = 8; - spi_message_add_tail(&t[1], &m); + + spi_message_init_with_transfers(&m, t, ARRAY_SIZE(t)); err = spi_sync(edev->spi, &m); /* have to wait at least Tcsl ns */ ndelay(250); if (err) { - dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n", - nbytes, (int)off, err); + dev_err(&edev->spi->dev, "read %zu bytes at %u: err. %d\n", + nbytes, off, err); break; } @@ -126,8 +173,7 @@ static int eeprom_93xx46_read(void *priv, unsigned int off, count -= nbytes; } - if (edev->pdata->finish) - edev->pdata->finish(edev); + gpiod_set_value_cansleep(edev->pdata->select, 0); mutex_unlock(&edev->lock); @@ -137,49 +183,45 @@ static int eeprom_93xx46_read(void *priv, unsigned int off, static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on) { struct spi_message m; - struct spi_transfer t; + struct spi_transfer t = {}; int bits, ret; u16 cmd_addr; + /* The opcode in front of the address is three bits. */ + bits = edev->addrlen + 3; + cmd_addr = OP_START << edev->addrlen; - if (edev->addrlen == 7) { + if (edev->pdata->flags & EE_ADDR8) cmd_addr |= (is_on ? ADDR_EWEN : ADDR_EWDS) << 1; - bits = 10; - } else { + else cmd_addr |= (is_on ? ADDR_EWEN : ADDR_EWDS); - bits = 9; - } if (has_quirk_instruction_length(edev)) { cmd_addr <<= 2; bits += 2; } - dev_dbg(&edev->spi->dev, "ew%s cmd 0x%04x, %d bits\n", - is_on ? "en" : "ds", cmd_addr, bits); - - spi_message_init(&m); - memset(&t, 0, sizeof(t)); + dev_dbg(&edev->spi->dev, "ew %s cmd 0x%04x, %d bits\n", + str_enable_disable(is_on), cmd_addr, bits); t.tx_buf = &cmd_addr; t.len = 2; t.bits_per_word = bits; - spi_message_add_tail(&t, &m); + + spi_message_init_with_transfers(&m, &t, 1); mutex_lock(&edev->lock); - if (edev->pdata->prepare) - edev->pdata->prepare(edev); + gpiod_set_value_cansleep(edev->pdata->select, 1); ret = spi_sync(edev->spi, &m); /* have to wait at least Tcsl ns */ ndelay(250); if (ret) - dev_err(&edev->spi->dev, "erase/write %sable error %d\n", - is_on ? "en" : "dis", ret); + dev_err(&edev->spi->dev, "erase/write %s error %d\n", + str_enable_disable(is_on), ret); - if (edev->pdata->finish) - edev->pdata->finish(edev); + gpiod_set_value_cansleep(edev->pdata->select, 0); mutex_unlock(&edev->lock); return ret; @@ -187,39 +229,40 @@ static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on) static ssize_t eeprom_93xx46_write_word(struct eeprom_93xx46_dev *edev, - const char *buf, unsigned off) + const char *buf, unsigned int off) { struct spi_message m; - struct spi_transfer t[2]; + struct spi_transfer t[2] = {}; int bits, data_len, ret; u16 cmd_addr; + if (unlikely(off >= edev->size)) + return -EINVAL; + + /* The opcode in front of the address is three bits. */ + bits = edev->addrlen + 3; + cmd_addr = OP_WRITE << edev->addrlen; - if (edev->addrlen == 7) { - cmd_addr |= off & 0x7f; - bits = 10; + if (edev->pdata->flags & EE_ADDR8) { + cmd_addr |= off; data_len = 1; } else { - cmd_addr |= (off >> 1) & 0x3f; - bits = 9; + cmd_addr |= (off >> 1); data_len = 2; } dev_dbg(&edev->spi->dev, "write cmd 0x%x\n", cmd_addr); - spi_message_init(&m); - memset(t, 0, sizeof(t)); - t[0].tx_buf = (char *)&cmd_addr; t[0].len = 2; t[0].bits_per_word = bits; - spi_message_add_tail(&t[0], &m); t[1].tx_buf = buf; t[1].len = data_len; t[1].bits_per_word = 8; - spi_message_add_tail(&t[1], &m); + + spi_message_init_with_transfers(&m, t, ARRAY_SIZE(t)); ret = spi_sync(edev->spi, &m); /* have to wait program cycle time Twc ms */ @@ -232,7 +275,8 @@ static int eeprom_93xx46_write(void *priv, unsigned int off, { struct eeprom_93xx46_dev *edev = priv; char *buf = val; - int i, ret, step = 1; + int ret, step = 1; + unsigned int i; if (unlikely(off >= edev->size)) return -EFBIG; @@ -242,7 +286,7 @@ static int eeprom_93xx46_write(void *priv, unsigned int off, return count; /* only write even number of bytes on 16-bit devices */ - if (edev->addrlen == 6) { + if (edev->pdata->flags & EE_ADDR16) { step = 2; count &= ~1; } @@ -254,20 +298,17 @@ static int eeprom_93xx46_write(void *priv, unsigned int off, mutex_lock(&edev->lock); - if (edev->pdata->prepare) - edev->pdata->prepare(edev); + gpiod_set_value_cansleep(edev->pdata->select, 1); for (i = 0; i < count; i += step) { ret = eeprom_93xx46_write_word(edev, &buf[i], off + i); if (ret) { - dev_err(&edev->spi->dev, "write failed at %d: %d\n", - (int)off + i, ret); + dev_err(&edev->spi->dev, "write failed at %u: %d\n", off + i, ret); break; } } - if (edev->pdata->finish) - edev->pdata->finish(edev); + gpiod_set_value_cansleep(edev->pdata->select, 0); mutex_unlock(&edev->lock); @@ -278,20 +319,19 @@ static int eeprom_93xx46_write(void *priv, unsigned int off, static int eeprom_93xx46_eral(struct eeprom_93xx46_dev *edev) { - struct eeprom_93xx46_platform_data *pd = edev->pdata; struct spi_message m; - struct spi_transfer t; + struct spi_transfer t = {}; int bits, ret; u16 cmd_addr; + /* The opcode in front of the address is three bits. */ + bits = edev->addrlen + 3; + cmd_addr = OP_START << edev->addrlen; - if (edev->addrlen == 7) { + if (edev->pdata->flags & EE_ADDR8) cmd_addr |= ADDR_ERAL << 1; - bits = 10; - } else { + else cmd_addr |= ADDR_ERAL; - bits = 9; - } if (has_quirk_instruction_length(edev)) { cmd_addr <<= 2; @@ -300,18 +340,15 @@ static int eeprom_93xx46_eral(struct eeprom_93xx46_dev *edev) dev_dbg(&edev->spi->dev, "eral cmd 0x%04x, %d bits\n", cmd_addr, bits); - spi_message_init(&m); - memset(&t, 0, sizeof(t)); - t.tx_buf = &cmd_addr; t.len = 2; t.bits_per_word = bits; - spi_message_add_tail(&t, &m); + + spi_message_init_with_transfers(&m, &t, 1); mutex_lock(&edev->lock); - if (edev->pdata->prepare) - edev->pdata->prepare(edev); + gpiod_set_value_cansleep(edev->pdata->select, 1); ret = spi_sync(edev->spi, &m); if (ret) @@ -319,21 +356,23 @@ static int eeprom_93xx46_eral(struct eeprom_93xx46_dev *edev) /* have to wait erase cycle time Tec ms */ mdelay(6); - if (pd->finish) - pd->finish(edev); + gpiod_set_value_cansleep(edev->pdata->select, 0); mutex_unlock(&edev->lock); return ret; } -static ssize_t eeprom_93xx46_store_erase(struct device *dev, - struct device_attribute *attr, - const char *buf, size_t count) +static ssize_t erase_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) { struct eeprom_93xx46_dev *edev = dev_get_drvdata(dev); - int erase = 0, ret; + bool erase; + int ret; + + ret = kstrtobool(buf, &erase); + if (ret) + return ret; - sscanf(buf, "%d", &erase); if (erase) { ret = eeprom_93xx46_ew(edev, 1); if (ret) @@ -347,47 +386,50 @@ static ssize_t eeprom_93xx46_store_erase(struct device *dev, } return count; } -static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase); - -static void select_assert(void *context) -{ - struct eeprom_93xx46_dev *edev = context; - - gpiod_set_value_cansleep(edev->pdata->select, 1); -} - -static void select_deassert(void *context) -{ - struct eeprom_93xx46_dev *edev = context; - - gpiod_set_value_cansleep(edev->pdata->select, 0); -} +static DEVICE_ATTR_WO(erase); static const struct of_device_id eeprom_93xx46_of_table[] = { - { .compatible = "eeprom-93xx46", }, + { .compatible = "eeprom-93xx46", .data = &at93c46_data, }, + { .compatible = "atmel,at93c46", .data = &at93c46_data, }, { .compatible = "atmel,at93c46d", .data = &atmel_at93c46d_data, }, + { .compatible = "atmel,at93c56", .data = &at93c56_data, }, + { .compatible = "atmel,at93c66", .data = &at93c66_data, }, + { .compatible = "microchip,93lc46b", .data = µchip_93lc46b_data, }, {} }; MODULE_DEVICE_TABLE(of, eeprom_93xx46_of_table); -static int eeprom_93xx46_probe_dt(struct spi_device *spi) +static const struct spi_device_id eeprom_93xx46_spi_ids[] = { + { .name = "eeprom-93xx46", + .driver_data = (kernel_ulong_t)&at93c46_data, }, + { .name = "at93c46", + .driver_data = (kernel_ulong_t)&at93c46_data, }, + { .name = "at93c46d", + .driver_data = (kernel_ulong_t)&atmel_at93c46d_data, }, + { .name = "at93c56", + .driver_data = (kernel_ulong_t)&at93c56_data, }, + { .name = "at93c66", + .driver_data = (kernel_ulong_t)&at93c66_data, }, + { .name = "93lc46b", + .driver_data = (kernel_ulong_t)µchip_93lc46b_data, }, + {} +}; +MODULE_DEVICE_TABLE(spi, eeprom_93xx46_spi_ids); + +static int eeprom_93xx46_probe_fw(struct device *dev) { - const struct of_device_id *of_id = - of_match_device(eeprom_93xx46_of_table, &spi->dev); - struct device_node *np = spi->dev.of_node; + const struct eeprom_93xx46_devtype_data *data; struct eeprom_93xx46_platform_data *pd; u32 tmp; - int gpio; - enum of_gpio_flags of_flags; int ret; - pd = devm_kzalloc(&spi->dev, sizeof(*pd), GFP_KERNEL); + pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL); if (!pd) return -ENOMEM; - ret = of_property_read_u32(np, "data-size", &tmp); + ret = device_property_read_u32(dev, "data-size", &tmp); if (ret < 0) { - dev_err(&spi->dev, "data-size property not found\n"); + dev_err(dev, "data-size property not found\n"); return ret; } @@ -396,37 +438,25 @@ static int eeprom_93xx46_probe_dt(struct spi_device *spi) } else if (tmp == 16) { pd->flags |= EE_ADDR16; } else { - dev_err(&spi->dev, "invalid data-size (%d)\n", tmp); + dev_err(dev, "invalid data-size (%d)\n", tmp); return -EINVAL; } - if (of_property_read_bool(np, "read-only")) + if (device_property_read_bool(dev, "read-only")) pd->flags |= EE_READONLY; - gpio = of_get_named_gpio_flags(np, "select-gpios", 0, &of_flags); - if (gpio_is_valid(gpio)) { - unsigned long flags = - of_flags == OF_GPIO_ACTIVE_LOW ? GPIOF_ACTIVE_LOW : 0; - - ret = devm_gpio_request_one(&spi->dev, gpio, flags, - "eeprom_93xx46_select"); - if (ret) - return ret; - - pd->select = gpio_to_desc(gpio); - pd->prepare = select_assert; - pd->finish = select_deassert; - - gpiod_direction_output(pd->select, 0); - } - - if (of_id->data) { - const struct eeprom_93xx46_devtype_data *data = of_id->data; + pd->select = devm_gpiod_get_optional(dev, "select", GPIOD_OUT_LOW); + if (IS_ERR(pd->select)) + return PTR_ERR(pd->select); + gpiod_set_consumer_name(pd->select, "93xx46 EEPROMs OE"); + data = spi_get_device_match_data(to_spi_device(dev)); + if (data) { pd->quirks = data->quirks; + pd->flags |= data->flags; } - spi->dev.platform_data = pd; + dev->platform_data = pd; return 0; } @@ -435,13 +465,12 @@ static int eeprom_93xx46_probe(struct spi_device *spi) { struct eeprom_93xx46_platform_data *pd; struct eeprom_93xx46_dev *edev; + struct device *dev = &spi->dev; int err; - if (spi->dev.of_node) { - err = eeprom_93xx46_probe_dt(spi); - if (err < 0) - return err; - } + err = eeprom_93xx46_probe_fw(dev); + if (err < 0) + return err; pd = spi->dev.platform_data; if (!pd) { @@ -449,18 +478,28 @@ static int eeprom_93xx46_probe(struct spi_device *spi) return -ENODEV; } - edev = kzalloc(sizeof(*edev), GFP_KERNEL); + edev = devm_kzalloc(&spi->dev, sizeof(*edev), GFP_KERNEL); if (!edev) return -ENOMEM; + if (pd->flags & EE_SIZE1K) + edev->size = 128; + else if (pd->flags & EE_SIZE2K) + edev->size = 256; + else if (pd->flags & EE_SIZE4K) + edev->size = 512; + else { + dev_err(&spi->dev, "unspecified size\n"); + return -EINVAL; + } + if (pd->flags & EE_ADDR8) - edev->addrlen = 7; + edev->addrlen = ilog2(edev->size); else if (pd->flags & EE_ADDR16) - edev->addrlen = 6; + edev->addrlen = ilog2(edev->size) - 1; else { dev_err(&spi->dev, "unspecified address type\n"); - err = -EINVAL; - goto fail; + return -EINVAL; } mutex_init(&edev->lock); @@ -468,7 +507,7 @@ static int eeprom_93xx46_probe(struct spi_device *spi) edev->spi = spi; edev->pdata = pd; - edev->size = 128; + edev->nvmem_config.type = NVMEM_TYPE_EEPROM; edev->nvmem_config.name = dev_name(&spi->dev); edev->nvmem_config.dev = &spi->dev; edev->nvmem_config.read_only = pd->flags & EE_READONLY; @@ -483,14 +522,13 @@ static int eeprom_93xx46_probe(struct spi_device *spi) edev->nvmem_config.word_size = 1; edev->nvmem_config.size = edev->size; - edev->nvmem = nvmem_register(&edev->nvmem_config); - if (IS_ERR(edev->nvmem)) { - err = PTR_ERR(edev->nvmem); - goto fail; - } + edev->nvmem = devm_nvmem_register(&spi->dev, &edev->nvmem_config); + if (IS_ERR(edev->nvmem)) + return PTR_ERR(edev->nvmem); - dev_info(&spi->dev, "%d-bit eeprom %s\n", + dev_info(&spi->dev, "%d-bit eeprom containing %d bytes %s\n", (pd->flags & EE_ADDR8) ? 8 : 16, + edev->size, (pd->flags & EE_READONLY) ? "(readonly)" : ""); if (!(pd->flags & EE_READONLY)) { @@ -500,31 +538,24 @@ static int eeprom_93xx46_probe(struct spi_device *spi) spi_set_drvdata(spi, edev); return 0; -fail: - kfree(edev); - return err; } -static int eeprom_93xx46_remove(struct spi_device *spi) +static void eeprom_93xx46_remove(struct spi_device *spi) { struct eeprom_93xx46_dev *edev = spi_get_drvdata(spi); - nvmem_unregister(edev->nvmem); - if (!(edev->pdata->flags & EE_READONLY)) device_remove_file(&spi->dev, &dev_attr_erase); - - kfree(edev); - return 0; } static struct spi_driver eeprom_93xx46_driver = { .driver = { .name = "93xx46", - .of_match_table = of_match_ptr(eeprom_93xx46_of_table), + .of_match_table = eeprom_93xx46_of_table, }, .probe = eeprom_93xx46_probe, .remove = eeprom_93xx46_remove, + .id_table = eeprom_93xx46_spi_ids, }; module_spi_driver(eeprom_93xx46_driver); |
