redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity

bq20z75: Add i2c retry mechanism

Browse source 
With the support of platform data, now adding support for option i2c
retries on read/write failures. Ths is specified through the optional
platform data.

Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
This commit is contained in:
Rhyland Klein 2011-02-28 16:55:29 -08:00 committed by Anton Vorontsov
parent bb87910160
commit ff28fcef1b
2 changed files with 33 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

37
drivers/power/bq20z75.c
View file

@ -156,30 +156,55 @@ struct bq20z75_info {
static int bq20z75_read_word_data(struct i2c_client *client, u8 address)
{
s32 ret;
struct bq20z75_info *bq20z75_device = i2c_get_clientdata(client);
s32 ret = 0;
int retries = 1;
if (bq20z75_device->pdata)
retries = max(bq20z75_device->pdata->i2c_retry_count + 1, 1);
while (retries > 0) {
ret = i2c_smbus_read_word_data(client, address);
if (ret >= 0)
break;
retries--;
}
ret = i2c_smbus_read_word_data(client, address);
if (ret < 0) {
dev_err(&client->dev,
dev_warn(&client->dev,
"%s: i2c read at address 0x%x failed\n",
__func__, address);
return ret;
}
return le16_to_cpu(ret);
}
static int bq20z75_write_word_data(struct i2c_client *client, u8 address,
u16 value)
{
s32 ret;
struct bq20z75_info *bq20z75_device = i2c_get_clientdata(client);
s32 ret = 0;
int retries = 1;
if (bq20z75_device->pdata)
retries = max(bq20z75_device->pdata->i2c_retry_count + 1, 1);
while (retries > 0) {
ret = i2c_smbus_write_word_data(client, address,
le16_to_cpu(value));
if (ret >= 0)
break;
retries--;
}
ret = i2c_smbus_write_word_data(client, address, le16_to_cpu(value));
if (ret < 0) {
dev_err(&client->dev,
dev_warn(&client->dev,
"%s: i2c write to address 0x%x failed\n",
__func__, address);
return ret;
}
return 0;
}

2
include/linux/power/bq20z75.h
View file

@ -28,10 +28,12 @@
* struct bq20z75_platform_data - platform data for bq20z75 devices
* @battery_detect: GPIO which is used to detect battery presence
* @battery_detect_present: gpio state when battery is present (0 / 1)
* @i2c_retry_count: # of times to retry on i2c IO failure
*/
struct bq20z75_platform_data {
int battery_detect;
int battery_detect_present;
int i2c_retry_count;
};
#endif