git.openwrt.org Git - openwrt/staging/xback.git/blob

   1 From d33d1214a1ddf9e7e4d14c62637518252927f0be Mon Sep 17 00:00:00 2001
   2 From: Lee Jones <lee@kernel.org>
   3 Date: Wed, 12 Jun 2024 16:36:40 +0100
   4 Subject: [PATCH] leds: core: Omit set_brightness error message for a LED
   5  supporting hw trigger only
   6
   7 If both set_brightness functions return -ENOTSUPP, then the LED doesn't
   8 support setting a fixed brightness value, and the error message isn't
   9 helpful. This can be the case e.g. for LEDs supporting a specific hw
  10 trigger only.
  11
  12 Pinched the subject line and commit message from Heiner:
  13 Link: https://lore.kernel.org/all/44177e37-9512-4044-8991-bb23b184bf37@gmail.com/
  14
  15 Reworked the function to provide Heiner's required semantics whilst
  16 simultaneously increasing readability and flow.
  17
  18 Cc: Pavel Machek <pavel@ucw.cz>
  19 Cc: linux-leds@vger.kernel.org
  20 Suggested-by: Heiner Kallweit <hkallweit1@gmail.com>
  21 Reviewed-by: Heiner Kallweit <hkallweit1@gmail.com>
  22 Signed-off-by: Lee Jones <lee@kernel.org>
  23 ---
  24  drivers/leds/led-core.c | 19 +++++++++++++------
  25  1 file changed, 13 insertions(+), 6 deletions(-)
  26
  27 --- a/drivers/leds/led-core.c
  28 +++ b/drivers/leds/led-core.c
  29 @@ -122,15 +122,22 @@ static void led_timer_function(struct ti
  30  static void set_brightness_delayed_set_brightness(struct led_classdev *led_cdev,
  31                                                   unsigned int value)
  32  {
  33 -       int ret = 0;
  34 +       int ret;
  35
  36         ret = __led_set_brightness(led_cdev, value);
  37 -       if (ret == -ENOTSUPP)
  38 +       if (ret == -ENOTSUPP) {
  39                 ret = __led_set_brightness_blocking(led_cdev, value);
  40 -       if (ret < 0 &&
  41 -           /* LED HW might have been unplugged, therefore don't warn */
  42 -           !(ret == -ENODEV && (led_cdev->flags & LED_UNREGISTERING) &&
  43 -           (led_cdev->flags & LED_HW_PLUGGABLE)))
  44 +               if (ret == -ENOTSUPP)
  45 +                       /* No back-end support to set a fixed brightness value */
  46 +                       return;
  47 +       }
  48 +
  49 +       /* LED HW might have been unplugged, therefore don't warn */
  50 +       if (ret == -ENODEV && led_cdev->flags & LED_UNREGISTERING &&
  51 +           led_cdev->flags & LED_HW_PLUGGABLE)
  52 +               return;
  53 +
  54 +       if (ret < 0)
  55                 dev_err(led_cdev->dev,
  56                         "Setting an LED's brightness failed (%d)\n", ret);
  57  }