diff options
| -rw-r--r-- | Documentation/devicetree/bindings/misc/at25.txt | 34 | ||||
| -rw-r--r-- | drivers/misc/eeprom/at25.c | 83 |
2 files changed, 82 insertions, 35 deletions
diff --git a/Documentation/devicetree/bindings/misc/at25.txt b/Documentation/devicetree/bindings/misc/at25.txt index ab3c327929d..1d3447165c3 100644 --- a/Documentation/devicetree/bindings/misc/at25.txt +++ b/Documentation/devicetree/bindings/misc/at25.txt @@ -1,21 +1,35 @@ -Atmel AT25 eeprom +EEPROMs (SPI) compatible with Atmel at25. Required properties: - compatible : "atmel,at25". - reg : chip select number - spi-max-frequency : max spi frequency to use +- pagesize : size of the eeprom page +- size : total eeprom size in bytes +- address-width : number of address bits (one of 8, 16, or 24) +Optional properties: +- spi-cpha : SPI shifted clock phase, as per spi-bus bindings. +- spi-cpol : SPI inverse clock polarity, as per spi-bus bindings. +- read-only : this parameter-less property disables writes to the eeprom + +Obsolete legacy properties are can be used in place of "size", "pagesize", +"address-width", and "read-only": - at25,byte-len : total eeprom size in bytes - at25,addr-mode : addr-mode flags, as defined in include/linux/spi/eeprom.h - at25,page-size : size of the eeprom page -Examples: -at25@0 { - compatible = "atmel,at25"; - reg = <0> - spi-max-frequency = <5000000>; +Additional compatible properties are also allowed. + +Example: + at25@0 { + compatible = "atmel,at25", "st,m95256"; + reg = <0> + spi-max-frequency = <5000000>; + spi-cpha; + spi-cpol; - at25,byte-len = <0x8000>; - at25,addr-mode = <2>; - at25,page-size = <64>; -}; + pagesize = <64>; + size = <32768>; + address-width = <16>; + }; diff --git a/drivers/misc/eeprom/at25.c b/drivers/misc/eeprom/at25.c index 25003d6ceb5..4ed93dd5411 100644 --- a/drivers/misc/eeprom/at25.c +++ b/drivers/misc/eeprom/at25.c @@ -302,6 +302,61 @@ static ssize_t at25_mem_write(struct memory_accessor *mem, const char *buf, /*-------------------------------------------------------------------------*/ +static int at25_np_to_chip(struct device *dev, + struct device_node *np, + struct spi_eeprom *chip) +{ + u32 val; + + memset(chip, 0, sizeof(*chip)); + strncpy(chip->name, np->name, sizeof(chip->name)); + + if (of_property_read_u32(np, "size", &val) == 0 || + of_property_read_u32(np, "at25,byte-len", &val) == 0) { + chip->byte_len = val; + } else { + dev_err(dev, "Error: missing \"size\" property\n"); + return -ENODEV; + } + + if (of_property_read_u32(np, "pagesize", &val) == 0 || + of_property_read_u32(np, "at25,page-size", &val) == 0) { + chip->page_size = (u16)val; + } else { + dev_err(dev, "Error: missing \"pagesize\" property\n"); + return -ENODEV; + } + + if (of_property_read_u32(np, "at25,addr-mode", &val) == 0) { + chip->flags = (u16)val; + } else { + if (of_property_read_u32(np, "address-width", &val)) { + dev_err(dev, + "Error: missing \"address-width\" property\n"); + return -ENODEV; + } + switch (val) { + case 8: + chip->flags |= EE_ADDR1; + break; + case 16: + chip->flags |= EE_ADDR2; + break; + case 24: + chip->flags |= EE_ADDR3; + break; + default: + dev_err(dev, + "Error: bad \"address-width\" property: %u\n", + val); + return -ENODEV; + } + if (of_find_property(np, "read-only", NULL)) + chip->flags |= EE_READONLY; + } + return 0; +} + static int at25_probe(struct spi_device *spi) { struct at25_data *at25 = NULL; @@ -314,33 +369,11 @@ static int at25_probe(struct spi_device *spi) /* Chip description */ if (!spi->dev.platform_data) { if (np) { - u32 val; - - memset(&chip, 0, sizeof(chip)); - strncpy(chip.name, np->name, 10); - - err = of_property_read_u32(np, "at25,byte-len", &val); - if (err) { - dev_dbg(&spi->dev, "invalid chip dt description\n"); - goto fail; - } - chip.byte_len = val; - - err = of_property_read_u32(np, "at25,addr-mode", &val); - if (err) { - dev_dbg(&spi->dev, "invalid chip dt description\n"); - goto fail; - } - chip.flags = (u16)val; - - err = of_property_read_u32(np, "at25,page-size", &val); - if (err) { - dev_dbg(&spi->dev, "invalid chip dt description\n"); + err = at25_np_to_chip(&spi->dev, np, &chip); + if (err) goto fail; - } - chip.page_size = (u16)val; } else { - dev_dbg(&spi->dev, "no chip description\n"); + dev_err(&spi->dev, "Error: no chip description\n"); err = -ENODEV; goto fail; } |