5.15-stable review patch. If anyone has any objections, please let me know.
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From: Marek Behún kabel@kernel.org
[ Upstream commit 730094577e0c37e1bc40be37cbd41f71b0a8a2a4 ]
The tty LED trigger uses the obsolete LED_ON & LED_OFF constants when setting LED brightness. This is bad because the LED_ON constant is equal to 1, and so when activating the tty LED trigger on a LED class device with max_brightness greater than 1, the LED is dimmer than it can be (when max_brightness is 255, the LED is very dimm indeed; some devices translate 1/255 to 0, so the LED is OFF all the time).
Instead of directly setting brightness to a specific value, use the led_blink_set_oneshot() function from LED core to configure the blink. This function takes the current configured brightness as blink brightness if not zero, and max brightness otherwise.
This also changes the behavior of the TTY LED trigger. Previously if rx/tx stats kept changing, the LED was ON all the time they kept changing. With this patch the LED will blink on TTY activity.
Fixes: fd4a641ac88f ("leds: trigger: implement a tty trigger") Signed-off-by: Marek Behún kabel@kernel.org Link: https://lore.kernel.org/r/20230802090753.13611-1-kabel@kernel.org Signed-off-by: Lee Jones lee@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/leds/trigger/ledtrig-tty.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/drivers/leds/trigger/ledtrig-tty.c b/drivers/leds/trigger/ledtrig-tty.c index f62db7e520b52..8ae0d2d284aff 100644 --- a/drivers/leds/trigger/ledtrig-tty.c +++ b/drivers/leds/trigger/ledtrig-tty.c @@ -7,6 +7,8 @@ #include <linux/tty.h> #include <uapi/linux/serial.h>
+#define LEDTRIG_TTY_INTERVAL 50 + struct ledtrig_tty_data { struct led_classdev *led_cdev; struct delayed_work dwork; @@ -122,17 +124,19 @@ static void ledtrig_tty_work(struct work_struct *work)
if (icount.rx != trigger_data->rx || icount.tx != trigger_data->tx) { - led_set_brightness_sync(trigger_data->led_cdev, LED_ON); + unsigned long interval = LEDTRIG_TTY_INTERVAL; + + led_blink_set_oneshot(trigger_data->led_cdev, &interval, + &interval, 0);
trigger_data->rx = icount.rx; trigger_data->tx = icount.tx; - } else { - led_set_brightness_sync(trigger_data->led_cdev, LED_OFF); }
out: mutex_unlock(&trigger_data->mutex); - schedule_delayed_work(&trigger_data->dwork, msecs_to_jiffies(100)); + schedule_delayed_work(&trigger_data->dwork, + msecs_to_jiffies(LEDTRIG_TTY_INTERVAL * 2)); }
static struct attribute *ledtrig_tty_attrs[] = {