[RFC] misc/at24: add experimental OF support for the generic eeprom driver

Wolfram Sang
2009-10-08T14:04:32Z

As Anton introduced archdata support, I wondered if this is a suitable way to
handle the platform_data/devicetree_property-dualism (at least for some
drivers).

If considered suitable, I would document the bindings properly. I really think
that pagesize deserves its own property as it is specific to the hardware and I
have seen devices with equal name and still having different pagesizes. Not too
sure about 'read-only' though, I just copied it from flash-partitions :)

Tested on a phyCORE-MPC5200-IO and build-tested on x86.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Anton Vorontsov <avorontsov@ru.mvista.com>
---
drivers/misc/eeprom/at24.c | 25 +++++++++++++++++++++++++
1 files changed, 25 insertions(+), 0 deletions(-)

diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index db39f4a..4e543e6 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -22,6 +22,9 @@
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/i2c/at24.h>
+#ifdef CONFIG_OF_I2C
+#include <linux/of.h>
+#endif

/*
* I2C EEPROMs from most vendors are inexpensive and mostly interchangeable.
@@ -414,6 +417,25 @@ static ssize_t at24_macc_write(struct memory_accessor *macc, const char *buf,
return at24_write(at24, buf, offset, count);
}

+#ifdef CONFIG_OF_I2C
+static void at24_get_ofdata(struct i2c_client *client, struct at24_platform_data *chip)
+{
+ const u32 *val;
+ struct device_node *node = dev_archdata_get_node(&client->dev.archdata);
+
+ if (node) {
+ if (of_get_property(node, "read-only", NULL))
+ chip->flags |= AT24_FLAG_READONLY;
+ val = of_get_property(node, "pagesize", NULL);
+ if (val)
+ chip->page_size = *val;
+ }
+}
+#else
+static void at24_get_ofdata(struct i2c_client *client, struct at24_platform_data *chip)
+{ }
+#endif
+
/*-------------------------------------------------------------------------*/

static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
@@ -444,6 +466,9 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
*/
chip.page_size = 1;

+ /* update chipdata if OF is present */
+ at24_get_ofdata(client, &chip);
+
chip.setup = NULL;
chip.context = NULL;
}
--
1.6.3.3