[PATCH 1/5] hwmon: (tmp102) Use devm_add_action to register cleanup function

Guenter Roeck
2016-06-24T00:28:46Z

By registering a cleanup function with devm_add_action(), we can
simplify the error path in the probe function and drop the remove
function entirely.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
drivers/hwmon/tmp102.c | 54 ++++++++++++++++++--------------------------------
1 file changed, 19 insertions(+), 35 deletions(-)

diff --git a/drivers/hwmon/tmp102.c b/drivers/hwmon/tmp102.c
index f1e96fd7f445..befd06b6f3a5 100644
--- a/drivers/hwmon/tmp102.c
+++ b/drivers/hwmon/tmp102.c
@@ -52,7 +52,6 @@

struct tmp102 {
struct i2c_client *client;
- struct device *hwmon_dev;
struct mutex lock;
u16 config_orig;
unsigned long last_update;
@@ -173,6 +172,15 @@ static const struct thermal_zone_of_device_ops tmp102_of_thermal_ops = {
.get_temp = tmp102_read_temp,
};

+static void tmp102_restore_config(void *data)
+{
+ struct tmp102 *tmp102 = data;
+ struct i2c_client *client = tmp102->client;
+
+ i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
+ tmp102->config_orig);
+}
+
static int tmp102_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@@ -201,66 +209,43 @@ static int tmp102_probe(struct i2c_client *client,
return status;
}
tmp102->config_orig = status;
+
+ devm_add_action(dev, tmp102_restore_config, tmp102);
+
status = i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
TMP102_CONFIG);
if (status < 0) {
dev_err(dev, "error writing config register\n");
- goto fail_restore_config;
+ return status;
}
status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
if (status < 0) {
dev_err(dev, "error reading config register\n");
- goto fail_restore_config;
+ return status;
}
status &= ~TMP102_CONFIG_RD_ONLY;
if (status != TMP102_CONFIG) {
dev_err(dev, "config settings did not stick\n");
- status = -ENODEV;
- goto fail_restore_config;
+ return -ENODEV;
}
tmp102->last_update = jiffies;
/* Mark that we are not ready with data until conversion is complete */
tmp102->first_time = true;
mutex_init(&tmp102->lock);

- hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
- tmp102, tmp102_groups);
+ hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+ tmp102,
+ tmp102_groups);
if (IS_ERR(hwmon_dev)) {
dev_dbg(dev, "unable to register hwmon device\n");
- status = PTR_ERR(hwmon_dev);
- goto fail_restore_config;
+ return PTR_ERR(hwmon_dev);
}
- tmp102->hwmon_dev = hwmon_dev;
devm_thermal_zone_of_sensor_register(hwmon_dev, 0, hwmon_dev,
&tmp102_of_thermal_ops);

dev_info(dev, "initialized\n");

return 0;
-
-fail_restore_config:
- i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
- tmp102->config_orig);
- return status;
-}
-
-static int tmp102_remove(struct i2c_client *client)
-{
- struct tmp102 *tmp102 = i2c_get_clientdata(client);
-
- hwmon_device_unregister(tmp102->hwmon_dev);
-
- /* Stop monitoring if device was stopped originally */
- if (tmp102->config_orig & TMP102_CONF_SD) {
- int config;
-
- config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
- if (config >= 0)
- i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
- config | TMP102_CONF_SD);
- }
-
- return 0;
}

#ifdef CONFIG_PM_SLEEP
@@ -303,7 +288,6 @@ static struct i2c_driver tmp102_driver = {
.driver.name = DRIVER_NAME,
.driver.pm = &tmp102_dev_pm_ops,
.probe = tmp102_probe,
- .remove = tmp102_remove,
.id_table = tmp102_id,
};

--
2.5.0