Commit dd905a61 authored by Ben Gardner's avatar Ben Gardner Committed by Wolfram Sang
Browse files

misc: eeprom: at24: use device_property_*() functions instead of of_get_property() 



Allow the at24 driver to get configuration information from both OF and
ACPI by using the more generic device_property functions.
This change was inspired by the at25.c driver.

I have a custom board with a ST M24C02 EEPROM attached to an I2C bus.
With the following ACPI construct, this patch instantiates a working
instance of the driver.

Device (EEP0) {
 Name (_HID, "PRP0001")
 Name (_DSD, Package () {
  ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
  Package () {
   Package () {"compatible", Package () {"st,24c02"}},
   Package () {"pagesize", 16},
  },
 })
 Name (_CRS, ResourceTemplate () {
  I2cSerialBus (
   0x0057, ControllerInitiated, 400000,
   AddressingMode7Bit, "\\_SB.PCI0.I2C3", 0x00,
   ResourceConsumer,,)
 })
}

Signed-off-by: default avatarBen Gardner <gardner.ben@gmail.com>
Reviewed-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent 465b2c4a

drivers/misc/eeprom/at24.c

+19 −26
Original line number Diff line number Diff line
@@ -19,7 +19,7 @@ 
#include <linux/log2.h>

#include <linux/bitops.h>

#include <linux/jiffies.h>

#include <linux/of.h>

#include <linux/property.h>

#include <linux/acpi.h>

#include <linux/i2c.h>

#include <linux/nvmem-provider.h>
@@ -562,26 +562,26 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count) 
	return 0;

}



#ifdef CONFIG_OF

static void at24_get_ofdata(struct i2c_client *client,

			    struct at24_platform_data *chip)

static void at24_get_pdata(struct device *dev, struct at24_platform_data *chip)

{

	const __be32 *val;

	struct device_node *node = client->dev.of_node;

	int err;

	u32 val;



	if (node) {

		if (of_get_property(node, "read-only", NULL))

	if (device_property_present(dev, "read-only"))

		chip->flags |= AT24_FLAG_READONLY;

		val = of_get_property(node, "pagesize", NULL);

		if (val)

			chip->page_size = be32_to_cpup(val);



	err = device_property_read_u32(dev, "pagesize", &val);

	if (!err) {

		chip->page_size = val;

	} else {

		/*

		 * This is slow, but we can't know all eeproms, so we better

		 * play safe. Specifying custom eeprom-types via platform_data

		 * is recommended anyhow.

		 */

		chip->page_size = 1;

	}

}

#else

static void at24_get_ofdata(struct i2c_client *client,

			    struct at24_platform_data *chip)

{ }

#endif /* CONFIG_OF */



static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)

{
@@ -613,15 +613,8 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) 
		chip.byte_len = BIT(magic & AT24_BITMASK(AT24_SIZE_BYTELEN));

		magic >>= AT24_SIZE_BYTELEN;

		chip.flags = magic & AT24_BITMASK(AT24_SIZE_FLAGS);

		/*

		 * This is slow, but we can't know all eeproms, so we better

		 * play safe. Specifying custom eeprom-types via platform_data

		 * is recommended anyhow.

		 */

		chip.page_size = 1;



		/* update chipdata if OF is present */

		at24_get_ofdata(client, &chip);

		at24_get_pdata(&client->dev, &chip);



		chip.setup = NULL;

		chip.context = NULL;

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