From 4b755999d6e0c1d988fb448289abb6c226cd8c36 Mon Sep 17 00:00:00 2001 From: Michael Hanselmann Date: Sun, 30 Jul 2006 03:04:19 -0700 Subject: [PATCH] powermac: More powermac backlight fixes This patch fixes several problems: - The legacy backlight value might be set at interrupt time. Introduced a worker to prevent it from directly calling the backlight code. - via-pmu allows the backlight to be grabbed, in which case we need to prevent other kernel code from changing the brightness. - Don't send PMU requests in via-pmu-backlight when the machine is about to sleep or waking up. - More Kconfig fixes. Signed-off-by: Michael Hanselmann Cc: Benjamin Herrenschmidt Cc: "Antonino A. Daplas" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/powerpc/platforms/powermac/backlight.c | 58 +++++++++++++++++++++++++++-- 1 file changed, 55 insertions(+), 3 deletions(-) (limited to 'arch/powerpc/platforms/powermac') diff --git a/arch/powerpc/platforms/powermac/backlight.c b/arch/powerpc/platforms/powermac/backlight.c index 74eed6b74cd..d6641549105 100644 --- a/arch/powerpc/platforms/powermac/backlight.c +++ b/arch/powerpc/platforms/powermac/backlight.c @@ -10,19 +10,32 @@ #include #include #include +#include +#include +#include #include #include #define OLD_BACKLIGHT_MAX 15 static void pmac_backlight_key_worker(void *data); +static void pmac_backlight_set_legacy_worker(void *data); + static DECLARE_WORK(pmac_backlight_key_work, pmac_backlight_key_worker, NULL); +static DECLARE_WORK(pmac_backlight_set_legacy_work, pmac_backlight_set_legacy_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 +/* Although these variables are used in interrupt context, it makes no sense to + * protect them. No user is able to produce enough key events per second and * notice the errors that might happen. */ static int pmac_backlight_key_queued; +static int pmac_backlight_set_legacy_queued; + +/* The via-pmu code allows the backlight to be grabbed, in which case the + * in-kernel control of the brightness needs to be disabled. This should + * only be used by really old PowerBooks. + */ +static atomic_t kernel_backlight_disabled = ATOMIC_INIT(0); /* Protect the pmac_backlight variable */ DEFINE_MUTEX(pmac_backlight_mutex); @@ -82,6 +95,9 @@ int pmac_backlight_curve_lookup(struct fb_info *info, int value) static void pmac_backlight_key_worker(void *data) { + if (atomic_read(&kernel_backlight_disabled)) + return; + mutex_lock(&pmac_backlight_mutex); if (pmac_backlight) { struct backlight_properties *props; @@ -107,8 +123,12 @@ static void pmac_backlight_key_worker(void *data) mutex_unlock(&pmac_backlight_mutex); } +/* This function is called in interrupt context */ void pmac_backlight_key(int direction) { + if (atomic_read(&kernel_backlight_disabled)) + return; + /* we can receive multiple interrupts here, but the scheduled work * will run only once, with the last value */ @@ -116,7 +136,7 @@ void pmac_backlight_key(int direction) schedule_work(&pmac_backlight_key_work); } -int pmac_backlight_set_legacy_brightness(int brightness) +static int __pmac_backlight_set_legacy_brightness(int brightness) { int error = -ENXIO; @@ -145,6 +165,28 @@ int pmac_backlight_set_legacy_brightness(int brightness) return error; } +static void pmac_backlight_set_legacy_worker(void *data) +{ + if (atomic_read(&kernel_backlight_disabled)) + return; + + __pmac_backlight_set_legacy_brightness(pmac_backlight_set_legacy_queued); +} + +/* This function is called in interrupt context */ +void pmac_backlight_set_legacy_brightness_pmu(int brightness) { + if (atomic_read(&kernel_backlight_disabled)) + return; + + pmac_backlight_set_legacy_queued = brightness; + schedule_work(&pmac_backlight_set_legacy_work); +} + +int pmac_backlight_set_legacy_brightness(int brightness) +{ + return __pmac_backlight_set_legacy_brightness(brightness); +} + int pmac_backlight_get_legacy_brightness() { int result = -ENXIO; @@ -167,6 +209,16 @@ int pmac_backlight_get_legacy_brightness() return result; } +void pmac_backlight_disable() +{ + atomic_inc(&kernel_backlight_disabled); +} + +void pmac_backlight_enable() +{ + atomic_dec(&kernel_backlight_disabled); +} + EXPORT_SYMBOL_GPL(pmac_backlight); EXPORT_SYMBOL_GPL(pmac_backlight_mutex); EXPORT_SYMBOL_GPL(pmac_has_backlight_type); -- cgit v1.2.3