target/linux/s3c24xx/patches-2.6.26/1206-From-3a32be40f78404d5f1185f0b3d6b5632381cb33f-Mon-Se.patch

   1 From 8279b4e4862b148b10e7d4d2967ac92eaae0f129 Mon Sep 17 00:00:00 2001
   2 From: Holger Freyther <zecke@openmoko.org>
   3 Date: Fri, 25 Jul 2008 23:06:18 +0100
   4 Subject: [PATCH] From 3a32be40f78404d5f1185f0b3d6b5632381cb33f Mon Sep 17 00:00:00 2001
   5  Subject: [PATCH] [neo1973 leds] Move from mutex to spinlock because we may not use mutexes
   6      The led triggers may call set_brightness from atomic contexts. As
   7      mutex_lock calls might_sleep and sleeping is not allowed in atomic contexts
   8      we have to switch to spinlocks here.
   9
  10 Signed-Off-By: Holger Freyther <zecke@openmoko.org>
  11 ---
  12  drivers/leds/leds-neo1973-gta02.c |   10 +++++-----
  13  1 files changed, 5 insertions(+), 5 deletions(-)
  14
  15 diff --git a/drivers/leds/leds-neo1973-gta02.c b/drivers/leds/leds-neo1973-gta02.c
  16 index 952ad69..8fe817b 100644
  17 --- a/drivers/leds/leds-neo1973-gta02.c
  18 +++ b/drivers/leds/leds-neo1973-gta02.c
  19 @@ -27,7 +27,7 @@
  20
  21  struct gta02_led_priv
  22  {
  23 -       struct mutex mutex;
  24 +       spinlock_t lock;
  25         struct led_classdev cdev;
  26         struct s3c2410_pwm pwm;
  27         unsigned int gpio;
  28 @@ -53,6 +53,7 @@ static inline struct gta02_led_bundle *to_bundle(struct led_classdev *led_cdev)
  29  static void gta02led_set(struct led_classdev *led_cdev,
  30                 enum led_brightness value)
  31  {
  32 +       unsigned long flags;
  33         struct gta02_led_priv *lp = to_priv(led_cdev);
  34
  35         /*
  36 @@ -60,7 +61,7 @@ static void gta02led_set(struct led_classdev *led_cdev,
  37          * value == 128 -> 50% duty cycle (medium power)
  38          * value == 0 -> 0% duty cycle (zero power)
  39          */
  40 -       mutex_lock(&lp->mutex);
  41 +       spin_lock_irqsave(&lp->lock, flags);
  42
  43         if (lp->has_pwm) {
  44                 s3c2410_pwm_duty_cycle(value, &lp->pwm);
  45 @@ -68,7 +69,7 @@ static void gta02led_set(struct led_classdev *led_cdev,
  46                 neo1973_gpb_setpin(lp->gpio, value ? 1 : 0);
  47         }
  48
  49 -       mutex_unlock(&lp->mutex);
  50 +       spin_unlock_irqrestore(&lp->lock, flags);
  51  }
  52
  53  #ifdef CONFIG_PM
  54 @@ -170,7 +171,7 @@ static int __init gta02led_probe(struct platform_device *pdev)
  55                         break;
  56                 }
  57
  58 -               mutex_init(&lp->mutex);
  59 +               spin_lock_init(&lp->lock);
  60                 rc = led_classdev_register(&pdev->dev, &lp->cdev);
  61         }
  62
  63 @@ -192,7 +193,6 @@ static int gta02led_remove(struct platform_device *pdev)
  64                         gta02led_set(&lp->cdev, 0);
  65
  66                 led_classdev_unregister(&lp->cdev);
  67 -               mutex_destroy(&lp->mutex);
  68         }
  69
  70         platform_set_drvdata(pdev, NULL);
  71 --
  72 1.5.6.3
  73