X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=sound%2Fdrivers%2Fpcsp%2Fpcsp_lib.c;h=e341f3f83b6a8ee2e1abd619a9014dadc19afd5b;hb=42619d35c7af2f88cad56425fe3981f1f65ff0bd;hp=7ad4a1534b2bf7e7099c6442950f7a20a58f99dd;hpb=8033c6e9736c29cce5f0d0abbca9a44dffb20c39;p=linux-2.6-omap-h63xx.git diff --git a/sound/drivers/pcsp/pcsp_lib.c b/sound/drivers/pcsp/pcsp_lib.c index 7ad4a1534b2..e341f3f83b6 100644 --- a/sound/drivers/pcsp/pcsp_lib.c +++ b/sound/drivers/pcsp/pcsp_lib.c @@ -9,7 +9,6 @@ #include #include #include -#include #include #include "pcsp.h" @@ -20,34 +19,8 @@ MODULE_PARM_DESC(nforce_wa, "Apply NForce chipset workaround " #define DMIX_WANTS_S16 1 -static void pcsp_start_timer(unsigned long dummy) -{ - hrtimer_start(&pcsp_chip.timer, ktime_set(0, 0), HRTIMER_MODE_REL); -} - -/* - * We need the hrtimer_start as a tasklet to avoid - * the nasty locking problem. :( - * The problem: - * - The timer handler is called with the cpu_base->lock - * already held by hrtimer code. - * - snd_pcm_period_elapsed() takes the - * substream->self_group.lock. - * So far so good. - * But the snd_pcsp_trigger() is called with the - * substream->self_group.lock held, and it calls - * hrtimer_start(), which takes the cpu_base->lock. - * You see the problem. We have the code pathes - * which take two locks in a reverse order. This - * can deadlock and the lock validator complains. - * The only solution I could find was to move the - * hrtimer_start() into a tasklet. -stsp - */ -static DECLARE_TASKLET(pcsp_start_timer_tasklet, pcsp_start_timer, 0); - enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle) { - unsigned long flags; unsigned char timer_cnt, val; int fmt_size, periods_elapsed; u64 ns; @@ -66,9 +39,7 @@ enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle) return HRTIMER_RESTART; } - /* hrtimer calls us from both hardirq and softirq contexts, - * so irqsave :( */ - spin_lock_irqsave(&chip->substream_lock, flags); + spin_lock_irq(&chip->substream_lock); /* Takashi Iwai says regarding this extra lock: If the irq handler handles some data on the DMA buffer, it should @@ -139,7 +110,7 @@ enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle) chip->period_ptr %= buffer_bytes; } - spin_unlock_irqrestore(&chip->substream_lock, flags); + spin_unlock_irq(&chip->substream_lock); if (!atomic_read(&chip->timer_active)) return HRTIMER_NORESTART; @@ -153,7 +124,7 @@ enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle) exit_nr_unlock2: snd_pcm_stream_unlock(substream); exit_nr_unlock1: - spin_unlock_irqrestore(&chip->substream_lock, flags); + spin_unlock_irq(&chip->substream_lock); return HRTIMER_NORESTART; } @@ -174,7 +145,7 @@ static void pcsp_start_playing(struct snd_pcsp *chip) atomic_set(&chip->timer_active, 1); chip->thalf = 0; - tasklet_schedule(&pcsp_start_timer_tasklet); + hrtimer_start(&pcsp_chip.timer, ktime_set(0, 0), HRTIMER_MODE_REL); } static void pcsp_stop_playing(struct snd_pcsp *chip)