diff options
| author | Dmitry Rokosov <ddrokosov@salutedevices.com> | 2024-09-04 01:39:30 +0300 |
|---|---|---|
| committer | Lee Jones <lee@kernel.org> | 2024-11-06 08:11:19 +0000 |
| commit | 32360bf6a5d4016669c3545e7b0ec939937f5331 (patch) | |
| tree | 4c98d0520190b9ca0ac53a0d602b05b571b957ed /drivers/leds | |
| parent | 64dd44a658065ab5595bbfe2cb4d8fd30c9e34a2 (diff) | |
leds: Introduce ordered workqueue for LEDs events instead of system_wq
This allows to setup ordered workqueue for LEDs events. This may be
useful, because default 'system_wq' does not guarantee execution order
of each work_struct, thus for several brightness update requests (for
multiple LEDs), real brightness switch could be in random order.
Yes, for sysfs-based LEDs we have flush_work() call inside
brightness_store() operation, but it's blocking call, so userspace
caller can be blocked at a long time, which means LEDs animation stream
can be broken.
Ordered workqueue has the same behaviour as system_wq + flush_work(),
but all scheduled works are async and userspace caller is not blocked,
which it better for userspace animation scheduling.
Signed-off-by: Alexey Romanov <avromanov@salutedevices.com>
Signed-off-by: Dmitry Rokosov <ddrokosov@salutedevices.com>
Link: https://lore.kernel.org/r/20240903223936.21292-1-ddrokosov@salutedevices.com
[Lee: Couple of style fix-ups]
Signed-off-by: Lee Jones <lee@kernel.org>
Diffstat (limited to 'drivers/leds')
| -rw-r--r-- | drivers/leds/led-class.c | 12 | ||||
| -rw-r--r-- | drivers/leds/led-core.c | 6 |
2 files changed, 14 insertions, 4 deletions
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index 06b97fd49ad9..83e512df47dc 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -25,6 +25,8 @@ static DEFINE_MUTEX(leds_lookup_lock); static LIST_HEAD(leds_lookup_list); +static struct workqueue_struct *leds_wq; + static ssize_t brightness_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -57,7 +59,6 @@ static ssize_t brightness_store(struct device *dev, if (state == LED_OFF) led_trigger_remove(led_cdev); led_set_brightness(led_cdev, state); - flush_work(&led_cdev->set_brightness_work); ret = size; unlock: @@ -549,6 +550,8 @@ int led_classdev_register_ext(struct device *parent, led_update_brightness(led_cdev); + led_cdev->wq = leds_wq; + led_init_core(led_cdev); #ifdef CONFIG_LEDS_TRIGGERS @@ -667,12 +670,19 @@ EXPORT_SYMBOL_GPL(devm_led_classdev_unregister); static int __init leds_init(void) { + leds_wq = alloc_ordered_workqueue("leds", 0); + if (!leds_wq) { + pr_err("Failed to create LEDs ordered workqueue\n"); + return -ENOMEM; + } + return class_register(&leds_class); } static void __exit leds_exit(void) { class_unregister(&leds_class); + destroy_workqueue(leds_wq); } subsys_initcall(leds_init); diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c index 001c290bc07b..f6c46d2e5276 100644 --- a/drivers/leds/led-core.c +++ b/drivers/leds/led-core.c @@ -273,7 +273,7 @@ void led_blink_set_nosleep(struct led_classdev *led_cdev, unsigned long delay_on led_cdev->delayed_delay_on = delay_on; led_cdev->delayed_delay_off = delay_off; set_bit(LED_SET_BLINK, &led_cdev->work_flags); - schedule_work(&led_cdev->set_brightness_work); + queue_work(led_cdev->wq, &led_cdev->set_brightness_work); return; } @@ -304,7 +304,7 @@ void led_set_brightness(struct led_classdev *led_cdev, unsigned int brightness) */ if (!brightness) { set_bit(LED_BLINK_DISABLE, &led_cdev->work_flags); - schedule_work(&led_cdev->set_brightness_work); + queue_work(led_cdev->wq, &led_cdev->set_brightness_work); } else { set_bit(LED_BLINK_BRIGHTNESS_CHANGE, &led_cdev->work_flags); @@ -340,7 +340,7 @@ void led_set_brightness_nopm(struct led_classdev *led_cdev, unsigned int value) set_bit(LED_SET_BRIGHTNESS_OFF, &led_cdev->work_flags); } - schedule_work(&led_cdev->set_brightness_work); + queue_work(led_cdev->wq, &led_cdev->set_brightness_work); } EXPORT_SYMBOL_GPL(led_set_brightness_nopm); |