diff options
author | Michael Hanselmann <linux-kernel@hansmi.ch> | 2006-07-10 04:44:45 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-07-10 13:24:20 -0700 |
commit | e01af0384f54023b4548b7742952da2ffcafd4cd (patch) | |
tree | 6ffd14821a0a1fedbf4430c5df7fa60822f4809f /arch/powerpc | |
parent | 58d383a6222d66be9483598c51bae34e7d3c2c37 (diff) |
[PATCH] powermac: Combined fixes for backlight code
This patch fixes several problems:
- pmac_backlight_key() is called under interrupt context, and therefore
can't use mutexes or semaphores, so defer the backlight level for
later, as it's not critical (original code by Aristeu S. Rozanski F.
<aris@valeta.org>).
- Add exports for functions that might be called from modules
- Fix Kconfig depdencies on PMAC_BACKLIGHT.
- Fix locking issues on calls from inside the driver (reported by
Aristeu S. Rozanski F., too)
- Fix wrong calculation of backlight values in some of the drivers
- Replace pmac_backlight_key_up/down by inline functions
[akpm@osdl.org: fix function prototypes]
Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch>
Acked-by: Aristeu S. Rozanski F. <aris@valeta.org>
Acked-by: Rene Nussbaumer <linux-kernel@killerfox.forkbomb.ch>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/powerpc')
-rw-r--r-- | arch/powerpc/platforms/powermac/backlight.c | 31 |
1 files changed, 22 insertions, 9 deletions
diff --git a/arch/powerpc/platforms/powermac/backlight.c b/arch/powerpc/platforms/powermac/backlight.c index 69f65e215a5c..74eed6b74cd6 100644 --- a/arch/powerpc/platforms/powermac/backlight.c +++ b/arch/powerpc/platforms/powermac/backlight.c @@ -15,6 +15,15 @@ #define OLD_BACKLIGHT_MAX 15 +static void pmac_backlight_key_worker(void *data); +static DECLARE_WORK(pmac_backlight_key_work, pmac_backlight_key_worker, NULL); + +/* Although this variable is used in interrupt context, it makes no sense to + * protect it. No user is able to produce enough key events per second and + * notice the errors that might happen. + */ +static int pmac_backlight_key_queued; + /* Protect the pmac_backlight variable */ DEFINE_MUTEX(pmac_backlight_mutex); @@ -71,7 +80,7 @@ int pmac_backlight_curve_lookup(struct fb_info *info, int value) return level; } -static void pmac_backlight_key(int direction) +static void pmac_backlight_key_worker(void *data) { mutex_lock(&pmac_backlight_mutex); if (pmac_backlight) { @@ -82,7 +91,8 @@ static void pmac_backlight_key(int direction) props = pmac_backlight->props; brightness = props->brightness + - ((direction?-1:1) * (props->max_brightness / 15)); + ((pmac_backlight_key_queued?-1:1) * + (props->max_brightness / 15)); if (brightness < 0) brightness = 0; @@ -97,14 +107,13 @@ static void pmac_backlight_key(int direction) mutex_unlock(&pmac_backlight_mutex); } -void pmac_backlight_key_up() +void pmac_backlight_key(int direction) { - pmac_backlight_key(0); -} - -void pmac_backlight_key_down() -{ - pmac_backlight_key(1); + /* we can receive multiple interrupts here, but the scheduled work + * will run only once, with the last value + */ + pmac_backlight_key_queued = direction; + schedule_work(&pmac_backlight_key_work); } int pmac_backlight_set_legacy_brightness(int brightness) @@ -157,3 +166,7 @@ int pmac_backlight_get_legacy_brightness() return result; } + +EXPORT_SYMBOL_GPL(pmac_backlight); +EXPORT_SYMBOL_GPL(pmac_backlight_mutex); +EXPORT_SYMBOL_GPL(pmac_has_backlight_type); |