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path: root/drivers/misc/eeprom/at24.c
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Diffstat (limited to 'drivers/misc/eeprom/at24.c')
-rw-r--r--drivers/misc/eeprom/at24.c43
1 files changed, 37 insertions, 6 deletions
diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index 559b0b3c16c..ab1ad41786d 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -20,6 +20,7 @@
#include <linux/log2.h>
#include <linux/bitops.h>
#include <linux/jiffies.h>
+#include <linux/of.h>
#include <linux/i2c.h>
#include <linux/i2c/at24.h>
@@ -457,6 +458,27 @@ static ssize_t at24_macc_write(struct memory_accessor *macc, const char *buf,
/*-------------------------------------------------------------------------*/
+#ifdef CONFIG_OF
+static void at24_get_ofdata(struct i2c_client *client,
+ struct at24_platform_data *chip)
+{
+ const __be32 *val;
+ struct device_node *node = client->dev.of_node;
+
+ 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 = be32_to_cpup(val);
+ }
+}
+#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)
{
struct at24_platform_data chip;
@@ -485,6 +507,9 @@ 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;
}
@@ -492,6 +517,11 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
if (!is_power_of_2(chip.byte_len))
dev_warn(&client->dev,
"byte_len looks suspicious (no power of 2)!\n");
+ if (!chip.page_size) {
+ dev_err(&client->dev, "page_size must not be 0!\n");
+ err = -EINVAL;
+ goto err_out;
+ }
if (!is_power_of_2(chip.page_size))
dev_warn(&client->dev,
"page_size looks suspicious (no power of 2)!\n");
@@ -597,19 +627,15 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
i2c_set_clientdata(client, at24);
- dev_info(&client->dev, "%zu byte %s EEPROM %s\n",
+ dev_info(&client->dev, "%zu byte %s EEPROM, %s, %u bytes/write\n",
at24->bin.size, client->name,
- writable ? "(writable)" : "(read-only)");
+ writable ? "writable" : "read-only", at24->write_max);
if (use_smbus == I2C_SMBUS_WORD_DATA ||
use_smbus == I2C_SMBUS_BYTE_DATA) {
dev_notice(&client->dev, "Falling back to %s reads, "
"performance will suffer\n", use_smbus ==
I2C_SMBUS_WORD_DATA ? "word" : "byte");
}
- dev_dbg(&client->dev,
- "page_size %d, num_addresses %d, write_max %d, use_smbus %d\n",
- chip.page_size, num_addresses,
- at24->write_max, use_smbus);
/* export data to kernel code */
if (chip.setup)
@@ -660,6 +686,11 @@ static struct i2c_driver at24_driver = {
static int __init at24_init(void)
{
+ if (!io_limit) {
+ pr_err("at24: io_limit must not be 0!\n");
+ return -EINVAL;
+ }
+
io_limit = rounddown_pow_of_two(io_limit);
return i2c_add_driver(&at24_driver);
}