Re: [PATCH] hwmon: g762: handle cleanup with devm_add_action

From: Guenter Roeck
Date: Wed Feb 28 2018 - 09:46:06 EST


On 02/28/2018 07:51 AM, Peng Hao wrote:
Simplify code and use devm_add_action() to handle cleanup.

Signed-off-by: Peng Hao <peng.hao2@xxxxxxxxxx>

Excellent idea. Some suggestions for improvements below.

---
drivers/hwmon/g762.c | 30 ++++++++++++++----------------
1 file changed, 14 insertions(+), 16 deletions(-)

diff --git a/drivers/hwmon/g762.c b/drivers/hwmon/g762.c
index 6d1208b..48e60d8 100644
--- a/drivers/hwmon/g762.c
+++ b/drivers/hwmon/g762.c
@@ -128,7 +128,6 @@ enum g762_regs {
G762_REG_FAN_CMD2_GEAR_MODE_1)) >> 2))
struct g762_data {
- struct device *hwmon_dev;
struct i2c_client *client;
struct clk *clk;
@@ -1051,9 +1050,17 @@ static inline int g762_fan_init(struct device *dev)
data->fan_cmd1);
}
+static void g762_remove(void *data)
+{
+ struct g762_data *g762 = data;
+ struct i2c_client *client = g762->client;
+
+ g762_of_clock_disable(client);
+}

You could instead just modify the arguments of g762_of_clock_disable()
and call it directly.

static int g762_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
+ struct device *hwmon_dev;
struct g762_data *data;
int ret;
@@ -1086,10 +1093,12 @@ static int g762_probe(struct i2c_client *client, const struct i2c_device_id *id)
if (ret)
goto clock_dis;
- data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
- data, g762_groups);
- if (IS_ERR(data->hwmon_dev)) {
- ret = PTR_ERR(data->hwmon_dev);
+ devm_add_action(dev, g762_remove, data);

Move this into g762_of_clock_enable(), just before the return, and the
dummy cleanup function can be dropped. You can then also drop the clock_dis:
label amd instead return immediately on errors.

+
+ hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+ data, g762_groups);
+ if (IS_ERR(hwmon_dev)) {
+ ret = PTR_ERR(hwmon_dev);
goto clock_dis;

Either case this would now be wrong since the cleanup is handled automatically.
This can be changed to
return PTR_ERR_OR_ZERO(hwmon_dev);

}
@@ -1101,23 +1110,12 @@ static int g762_probe(struct i2c_client *client, const struct i2c_device_id *id)
return ret;
}
-static int g762_remove(struct i2c_client *client)
-{
- struct g762_data *data = i2c_get_clientdata(client);
-
- hwmon_device_unregister(data->hwmon_dev);
- g762_of_clock_disable(client);
-
- return 0;
-}
-
static struct i2c_driver g762_driver = {
.driver = {
.name = DRVNAME,
.of_match_table = of_match_ptr(g762_dt_match),
},
.probe = g762_probe,
- .remove = g762_remove,
.id_table = g762_id,
};