Re: [PATCH 1/2] hwmon: (asus_atk0110) Replace deprecated device register call

From: Guenter Roeck
Date: Thu May 31 2018 - 10:27:31 EST


Hi Bastian,

On 05/31/2018 07:01 AM, Bastian Germann wrote:
Make the asus_atk0110 driver use hwmon_device_register_with_groups instead
of the deprecated hwmon_device_register.
Construct the expected attribute_group array from the sensor list which
contains all needed attributes.

Signed-off-by: Bastian Germann <bastiangermann@xxxxxxxxxxx>
---
drivers/hwmon/asus_atk0110.c | 71 +++++++++++++++++++++++++++++-------
1 file changed, 58 insertions(+), 13 deletions(-)

diff --git a/drivers/hwmon/asus_atk0110.c b/drivers/hwmon/asus_atk0110.c
index 975c43d446f8..8a35fb27ff50 100644
--- a/drivers/hwmon/asus_atk0110.c
+++ b/drivers/hwmon/asus_atk0110.c
@@ -125,6 +125,7 @@ struct atk_data {
int temperature_count;
int fan_count;
struct list_head sensor_list;
+ const struct attribute_group **attr_groups;
struct {
struct dentry *root;
@@ -1242,27 +1243,67 @@ static void atk_free_sensors(struct atk_data *data)
}
}
+static int atk_init_attribute_groups(struct atk_data *data)
+{
+ struct atk_sensor_data *s;
+ struct attribute **attrs;
+ struct attribute_group *group;
+ const struct attribute_group **groups;
+ int i = 0;
+ int len = (data->voltage_count + data->temperature_count
+ + data->fan_count) * 4 + 1;
+
+ attrs = kcalloc(len, sizeof(struct attribute *), GFP_KERNEL);

Please use devm_kcalloc().

+ if (!attrs)
+ return -ENOMEM;
+
+ list_for_each_entry(s, &data->sensor_list, list) {
+ attrs[i++] = &s->input_attr.attr;
+ attrs[i++] = &s->label_attr.attr;
+ attrs[i++] = &s->limit1_attr.attr;
+ attrs[i++] = &s->limit2_attr.attr;
+ }
+ attrs[i] = NULL;
+
+ group = kzalloc(sizeof(*group), GFP_KERNEL);

devm_kzalloc()

+ if (!group)
+ goto cleanup;
+ group->attrs = attrs;
+
+ groups = kcalloc(2, sizeof(struct attribute_group *), GFP_KERNEL);

devm_kcalloc()

+ if (!groups) {
+ kfree(group);
+ goto cleanup;
+ }
+ groups[0] = group;
+ groups[1] = NULL;

kcalloc() clears the allocated memory, so this is unnecessary. However,
I would suggest to make group and groups part of struct atk_sensor_data.
The size is static, and the fields will always be needed, so dynamic
allocation doesn't buy anything except overhead.

+ data->attr_groups = groups;
+ > + return 0;
+cleanup:
+ kfree(attrs);

then you won't need the kfree() calls.

The same should be done with the existing calls of kzalloc(),
but that should be a separate patch.

+ return -ENOMEM;
+}
+
+static void atk_free_attribute_groups(struct atk_data *data)
+{
+ kfree(data->attr_groups[0]->attrs);
+ kfree(data->attr_groups[0]);
+ kfree(data->attr_groups);
+}
+
static int atk_register_hwmon(struct atk_data *data)
{
struct device *dev = &data->acpi_dev->dev;
- int err;
dev_dbg(dev, "registering hwmon device\n");
- data->hwmon_dev = hwmon_device_register(dev);
+ data->hwmon_dev = hwmon_device_register_with_groups(dev, "atk0110",
+ data,
+ data->attr_groups);
if (IS_ERR(data->hwmon_dev))
return PTR_ERR(data->hwmon_dev);
- dev_dbg(dev, "populating sysfs directory\n");
- err = atk_create_files(data);
- if (err)
- goto remove;
-
return 0;
-remove:
- /* Cleanup the registered files */
- atk_remove_files(data);
- hwmon_device_unregister(data->hwmon_dev);
- return err;
}
static int atk_probe_if(struct atk_data *data)
@@ -1397,6 +1438,9 @@ static int atk_add(struct acpi_device *device)
goto out;
}
+ err = atk_init_attribute_groups(data);
+ if (err)
+ goto out;
err = atk_register_hwmon(data);
if (err)
goto cleanup;
@@ -1407,6 +1451,7 @@ static int atk_add(struct acpi_device *device)
return 0;
cleanup:
atk_free_sensors(data);
+ atk_free_attribute_groups(data);
out:
if (data->disable_ec)
atk_ec_ctl(data, 0);
@@ -1423,9 +1468,9 @@ static int atk_remove(struct acpi_device *device)
atk_debugfs_cleanup(data);
- atk_remove_files(data);

You should also remove the no longer needed functions as well as the
name attribute.

atk_free_sensors(data);
hwmon_device_unregister(data->hwmon_dev);
+ atk_free_attribute_groups(data);
if (data->disable_ec) {
if (atk_ec_ctl(data, 0))