diff options
| -rw-r--r-- | drivers/misc/eeprom/eeprom_93xx46.c | 126 | ||||
| -rw-r--r-- | include/linux/eeprom_93xx46.h | 6 |
2 files changed, 97 insertions, 35 deletions
diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c index f0c30b366218..a3c3136abf3e 100644 --- a/drivers/misc/eeprom/eeprom_93xx46.c +++ b/drivers/misc/eeprom/eeprom_93xx46.c @@ -27,6 +27,15 @@ #define ADDR_ERAL 0x20 #define ADDR_EWEN 0x30 +struct eeprom_93xx46_devtype_data { + unsigned int quirks; +}; + +static const struct eeprom_93xx46_devtype_data atmel_at93c46d_data = { + .quirks = EEPROM_93XX46_QUIRK_SINGLE_WORD_READ | + EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH, +}; + struct eeprom_93xx46_dev { struct spi_device *spi; struct eeprom_93xx46_platform_data *pdata; @@ -35,6 +44,16 @@ struct eeprom_93xx46_dev { int addrlen; }; +static inline bool has_quirk_single_word_read(struct eeprom_93xx46_dev *edev) +{ + return edev->pdata->quirks & EEPROM_93XX46_QUIRK_SINGLE_WORD_READ; +} + +static inline bool has_quirk_instruction_length(struct eeprom_93xx46_dev *edev) +{ + return edev->pdata->quirks & EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH; +} + static ssize_t eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, @@ -42,58 +61,73 @@ eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj, { struct eeprom_93xx46_dev *edev; struct device *dev; - struct spi_message m; - struct spi_transfer t[2]; - int bits, ret; - u16 cmd_addr; + ssize_t ret = 0; dev = kobj_to_dev(kobj); edev = dev_get_drvdata(dev); - cmd_addr = OP_READ << edev->addrlen; + mutex_lock(&edev->lock); - if (edev->addrlen == 7) { - cmd_addr |= off & 0x7f; - bits = 10; - } else { - cmd_addr |= (off >> 1) & 0x3f; - bits = 9; - } + if (edev->pdata->prepare) + edev->pdata->prepare(edev); - dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n", - cmd_addr, edev->spi->max_speed_hz); + while (count) { + struct spi_message m; + struct spi_transfer t[2] = { { 0 } }; + u16 cmd_addr = OP_READ << edev->addrlen; + size_t nbytes = count; + int bits; + int err; + + if (edev->addrlen == 7) { + cmd_addr |= off & 0x7f; + bits = 10; + if (has_quirk_single_word_read(edev)) + nbytes = 1; + } else { + cmd_addr |= (off >> 1) & 0x3f; + bits = 9; + if (has_quirk_single_word_read(edev)) + nbytes = 2; + } - spi_message_init(&m); - memset(t, 0, sizeof(t)); + dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n", + cmd_addr, edev->spi->max_speed_hz); - t[0].tx_buf = (char *)&cmd_addr; - t[0].len = 2; - t[0].bits_per_word = bits; - spi_message_add_tail(&t[0], &m); + spi_message_init(&m); - t[1].rx_buf = buf; - t[1].len = count; - t[1].bits_per_word = 8; - spi_message_add_tail(&t[1], &m); + t[0].tx_buf = (char *)&cmd_addr; + t[0].len = 2; + t[0].bits_per_word = bits; + spi_message_add_tail(&t[0], &m); - mutex_lock(&edev->lock); + t[1].rx_buf = buf; + t[1].len = count; + t[1].bits_per_word = 8; + spi_message_add_tail(&t[1], &m); - if (edev->pdata->prepare) - edev->pdata->prepare(edev); + err = spi_sync(edev->spi, &m); + /* have to wait at least Tcsl ns */ + ndelay(250); - ret = spi_sync(edev->spi, &m); - /* have to wait at least Tcsl ns */ - ndelay(250); - if (ret) { - dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n", - count, (int)off, ret); + if (err) { + dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n", + nbytes, (int)off, err); + ret = err; + break; + } + + buf += nbytes; + off += nbytes; + count -= nbytes; + ret += nbytes; } if (edev->pdata->finish) edev->pdata->finish(edev); mutex_unlock(&edev->lock); - return ret ? : count; + return ret; } static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on) @@ -112,7 +146,13 @@ static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on) bits = 9; } - dev_dbg(&edev->spi->dev, "ew cmd 0x%04x\n", cmd_addr); + 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)); @@ -247,6 +287,13 @@ static int eeprom_93xx46_eral(struct eeprom_93xx46_dev *edev) bits = 9; } + if (has_quirk_instruction_length(edev)) { + cmd_addr <<= 2; + bits += 2; + } + + dev_dbg(&edev->spi->dev, "eral cmd 0x%04x, %d bits\n", cmd_addr, bits); + spi_message_init(&m); memset(&t, 0, sizeof(t)); @@ -298,12 +345,15 @@ static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase); static const struct of_device_id eeprom_93xx46_of_table[] = { { .compatible = "eeprom-93xx46", }, + { .compatible = "atmel,at93c46d", .data = &atmel_at93c46d_data, }, {} }; MODULE_DEVICE_TABLE(of, eeprom_93xx46_of_table); static int eeprom_93xx46_probe_dt(struct spi_device *spi) { + const struct of_device_id *of_id = + of_match_device(eeprom_93xx46_of_table, &spi->dev); struct device_node *np = spi->dev.of_node; struct eeprom_93xx46_platform_data *pd; u32 tmp; @@ -331,6 +381,12 @@ static int eeprom_93xx46_probe_dt(struct spi_device *spi) if (of_property_read_bool(np, "read-only")) pd->flags |= EE_READONLY; + if (of_id->data) { + const struct eeprom_93xx46_devtype_data *data = of_id->data; + + pd->quirks = data->quirks; + } + spi->dev.platform_data = pd; return 0; diff --git a/include/linux/eeprom_93xx46.h b/include/linux/eeprom_93xx46.h index 06791811e49d..92fa4c37ac1f 100644 --- a/include/linux/eeprom_93xx46.h +++ b/include/linux/eeprom_93xx46.h @@ -9,6 +9,12 @@ struct eeprom_93xx46_platform_data { #define EE_ADDR16 0x02 /* 16 bit addr. cfg */ #define EE_READONLY 0x08 /* forbid writing */ + 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) + /* * optional hooks to control additional logic * before and after spi transfer. |