misc: at25: Parse dt settings

This adds dt support to the at25 eeprom driver.

Signed-off-by: Alexandre Pereira da Silva <aletes.xgr@gmail.com>
Tested-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Alexandre Pereira da Silva 2012-06-14 09:59:23 -03:00 committed by Greg Kroah-Hartman
parent 98dcd59dd0
commit 002176db81
2 changed files with 66 additions and 16 deletions

View File

@ -0,0 +1,21 @@
Atmel AT25 eeprom
Required properties:
- compatible : "atmel,at25".
- reg : chip select number
- spi-max-frequency : max spi frequency to use
- 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>;
at25,byte-len = <0x8000>;
at25,addr-mode = <2>;
at25,page-size = <64>;
};

View File

@ -19,7 +19,7 @@
#include <linux/spi/spi.h>
#include <linux/spi/eeprom.h>
#include <linux/of.h>
/*
* NOTE: this is an *EEPROM* driver. The vagaries of product naming
@ -305,25 +305,54 @@ static ssize_t at25_mem_write(struct memory_accessor *mem, const char *buf,
static int at25_probe(struct spi_device *spi)
{
struct at25_data *at25 = NULL;
const struct spi_eeprom *chip;
struct spi_eeprom chip;
struct device_node *np = spi->dev.of_node;
int err;
int sr;
int addrlen;
/* Chip description */
chip = spi->dev.platform_data;
if (!chip) {
dev_dbg(&spi->dev, "no chip description\n");
err = -ENODEV;
goto fail;
}
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");
goto fail;
}
chip.page_size = (u16)val;
} else {
dev_dbg(&spi->dev, "no chip description\n");
err = -ENODEV;
goto fail;
}
} else
chip = *(struct spi_eeprom *)spi->dev.platform_data;
/* For now we only support 8/16/24 bit addressing */
if (chip->flags & EE_ADDR1)
if (chip.flags & EE_ADDR1)
addrlen = 1;
else if (chip->flags & EE_ADDR2)
else if (chip.flags & EE_ADDR2)
addrlen = 2;
else if (chip->flags & EE_ADDR3)
else if (chip.flags & EE_ADDR3)
addrlen = 3;
else {
dev_dbg(&spi->dev, "unsupported address type\n");
@ -348,7 +377,7 @@ static int at25_probe(struct spi_device *spi)
}
mutex_init(&at25->lock);
at25->chip = *chip;
at25->chip = chip;
at25->spi = spi_dev_get(spi);
dev_set_drvdata(&spi->dev, at25);
at25->addrlen = addrlen;
@ -369,7 +398,7 @@ static int at25_probe(struct spi_device *spi)
at25->mem.read = at25_mem_read;
at25->bin.size = at25->chip.byte_len;
if (!(chip->flags & EE_READONLY)) {
if (!(chip.flags & EE_READONLY)) {
at25->bin.write = at25_bin_write;
at25->bin.attr.mode |= S_IWUSR;
at25->mem.write = at25_mem_write;
@ -379,8 +408,8 @@ static int at25_probe(struct spi_device *spi)
if (err)
goto fail;
if (chip->setup)
chip->setup(&at25->mem, chip->context);
if (chip.setup)
chip.setup(&at25->mem, chip.context);
dev_info(&spi->dev, "%Zd %s %s eeprom%s, pagesize %u\n",
(at25->bin.size < 1024)
@ -388,7 +417,7 @@ static int at25_probe(struct spi_device *spi)
: (at25->bin.size / 1024),
(at25->bin.size < 1024) ? "Byte" : "KByte",
at25->chip.name,
(chip->flags & EE_READONLY) ? " (readonly)" : "",
(chip.flags & EE_READONLY) ? " (readonly)" : "",
at25->chip.page_size);
return 0;
fail: