leds: triggers: add device attribute support

As many triggers use device attributes, add support for these in
led_trigger_set which allows simplifying the drivers accordingly.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
This commit is contained in:
Uwe Kleine-König 2018-07-02 22:05:22 +02:00 committed by Jacek Anaszewski
parent 2282e125a4
commit a7e7a31563
2 changed files with 23 additions and 0 deletions

View file

@ -127,6 +127,7 @@ int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig)
led_stop_software_blink(led_cdev);
if (led_cdev->trigger->deactivate)
led_cdev->trigger->deactivate(led_cdev);
device_remove_groups(led_cdev->dev, led_cdev->trigger->groups);
led_cdev->trigger = NULL;
led_set_brightness(led_cdev, LED_OFF);
}
@ -143,6 +144,12 @@ int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig)
if (ret)
goto err_activate;
ret = device_add_groups(led_cdev->dev, trig->groups);
if (ret) {
dev_err(led_cdev->dev, "Failed to add trigger attributes\n");
goto err_add_groups;
}
}
if (event) {
@ -156,7 +163,12 @@ int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig)
return 0;
err_add_groups:
if (trig->deactivate)
trig->deactivate(led_cdev);
err_activate:
led_cdev->trigger = NULL;
write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags);
list_del(&led_cdev->trig_list);

View file

@ -262,8 +262,19 @@ struct led_trigger {
/* Link to next registered trigger */
struct list_head next_trig;
const struct attribute_group **groups;
};
/*
* Currently the attributes in struct led_trigger::groups are added directly to
* the LED device. As this might change in the future, the following
* macros abstract getting the LED device and its trigger_data from the dev
* parameter passed to the attribute accessor functions.
*/
#define led_trigger_get_led(dev) ((struct led_classdev *)dev_get_drvdata((dev)))
#define led_trigger_get_drvdata(dev) (led_get_trigger_data(led_trigger_get_led(dev)))
ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count);
ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,