2017-12-01 18:04:46

by Sven Van Asbroeck

[permalink] [raw]
Subject: [PATCH] eeprom: at24: fix I2C device selection for runtime PM

From: Sakari Ailus <[email protected]>

The at24 driver creates dummy I2C devices to access offsets in the chip
that are outside the area supported using a single I2C address. It is not
meaningful to use runtime PM to such devices; the system firmware (ACPI)
does not know about these devices nor runtime PM was enabled for them.
Always use the real device instead of the dummy ones.

Fixes: 98e8201039af ("eeprom: at24: enable runtime pm support")
Signed-off-by: Sakari Ailus <[email protected]>
Tested-by: Sven Van Asbroeck on a 24AA16/24LC16B <[email protected]>
[Bartosz: rebased on top of previous fixes for 4.15, tweaked the
commit message]
[Sven: fixed Bartosz's rebase]
Signed-off-by: Sven Van Asbroeck <[email protected]>
Signed-off-by: Bartosz Golaszewski <[email protected]>
---
drivers/misc/eeprom/at24.c | 24 ++++++++++--------------
1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index e0b4b36..07b6b61 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -561,18 +561,16 @@ static ssize_t at24_eeprom_write_i2c(struct at24_data *at24, const char *buf,
static int at24_read(void *priv, unsigned int off, void *val, size_t count)
{
struct at24_data *at24 = priv;
- struct i2c_client *client;
+ struct device *dev = &at24->client[0]->dev;
char *buf = val;
int ret;

if (unlikely(!count))
return count;

- client = at24_translate_offset(at24, &off);
-
- ret = pm_runtime_get_sync(&client->dev);
+ ret = pm_runtime_get_sync(dev);
if (ret < 0) {
- pm_runtime_put_noidle(&client->dev);
+ pm_runtime_put_noidle(dev);
return ret;
}

@@ -588,7 +586,7 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count)
status = at24->read_func(at24, buf, off, count);
if (status < 0) {
mutex_unlock(&at24->lock);
- pm_runtime_put(&client->dev);
+ pm_runtime_put(dev);
return status;
}
buf += status;
@@ -598,7 +596,7 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count)

mutex_unlock(&at24->lock);

- pm_runtime_put(&client->dev);
+ pm_runtime_put(dev);

return 0;
}
@@ -606,18 +604,16 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count)
static int at24_write(void *priv, unsigned int off, void *val, size_t count)
{
struct at24_data *at24 = priv;
- struct i2c_client *client;
+ struct device *dev = &at24->client[0]->dev;
char *buf = val;
int ret;

if (unlikely(!count))
return -EINVAL;

- client = at24_translate_offset(at24, &off);
-
- ret = pm_runtime_get_sync(&client->dev);
+ ret = pm_runtime_get_sync(dev);
if (ret < 0) {
- pm_runtime_put_noidle(&client->dev);
+ pm_runtime_put_noidle(dev);
return ret;
}

@@ -633,7 +629,7 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count)
status = at24->write_func(at24, buf, off, count);
if (status < 0) {
mutex_unlock(&at24->lock);
- pm_runtime_put(&client->dev);
+ pm_runtime_put(dev);
return status;
}
buf += status;
@@ -643,7 +639,7 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count)

mutex_unlock(&at24->lock);

- pm_runtime_put(&client->dev);
+ pm_runtime_put(dev);

return 0;
}
--
1.9.1


2017-12-01 18:35:56

by Sven Van Asbroeck

[permalink] [raw]
Subject: Re: [PATCH] eeprom: at24: fix I2C device selection for runtime PM

I'm not sure what happened here, but the patch is against the wrong tree.
I will fix and resend the patch, and mark it clearly as [PATCH v2].