From c631d03c6873b9e17906556e84fcafc42f26a7c2 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 3 Sep 2009 15:59:26 +0200 Subject: [PATCH] ALSA: dummy - Support high-res timer mode Allow snd-dummy driver to use high-res timer as its timing source instead of the system timer. The new module option "hrtimer" is added to turn on/off the high-res timer support. It can be switched even dynamically via sysfs. Signed-off-by: Takashi Iwai --- sound/drivers/dummy.c | 413 ++++++++++++++++++++++++++++-------------- 1 file changed, 272 insertions(+), 141 deletions(-) diff --git a/sound/drivers/dummy.c b/sound/drivers/dummy.c index 54239d2e0997..f387d53e5039 100644 --- a/sound/drivers/dummy.c +++ b/sound/drivers/dummy.c @@ -25,6 +25,8 @@ #include #include #include +#include +#include #include #include #include @@ -148,6 +150,9 @@ static int enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0}; static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1}; static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8}; //static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2}; +#ifdef CONFIG_HIGH_RES_TIMERS +static int hrtimer = 1; +#endif module_param_array(index, int, NULL, 0444); MODULE_PARM_DESC(index, "Index value for dummy soundcard."); @@ -161,6 +166,10 @@ module_param_array(pcm_substreams, int, NULL, 0444); MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-16) for dummy driver."); //module_param_array(midi_devs, int, NULL, 0444); //MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver."); +#ifdef CONFIG_HIGH_RES_TIMERS +module_param(hrtimer, bool, 0644); +MODULE_PARM_DESC(hrtimer, "Use hrtimer as the timer source."); +#endif static struct platform_device *devices[SNDRV_CARDS]; @@ -171,16 +180,29 @@ static struct platform_device *devices[SNDRV_CARDS]; #define MIXER_ADDR_CD 4 #define MIXER_ADDR_LAST 4 +struct dummy_timer_ops { + int (*create)(struct snd_pcm_substream *); + void (*free)(struct snd_pcm_substream *); + int (*prepare)(struct snd_pcm_substream *); + int (*start)(struct snd_pcm_substream *); + int (*stop)(struct snd_pcm_substream *); + snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *); +}; + struct snd_dummy { struct snd_card *card; struct snd_pcm *pcm; spinlock_t mixer_lock; int mixer_volume[MIXER_ADDR_LAST+1][2]; int capture_source[MIXER_ADDR_LAST+1][2]; + const struct dummy_timer_ops *timer_ops; }; -struct snd_dummy_pcm { - struct snd_dummy *dummy; +/* + * system timer interface + */ + +struct dummy_systimer_pcm { spinlock_t lock; struct timer_list timer; unsigned int pcm_buffer_size; @@ -192,46 +214,29 @@ struct snd_dummy_pcm { struct snd_pcm_substream *substream; }; - -static inline void snd_card_dummy_pcm_timer_start(struct snd_dummy_pcm *dpcm) +static int dummy_systimer_start(struct snd_pcm_substream *substream) { + struct dummy_systimer_pcm *dpcm = substream->runtime->private_data; + spin_lock(&dpcm->lock); dpcm->timer.expires = 1 + jiffies; add_timer(&dpcm->timer); + spin_unlock(&dpcm->lock); + return 0; } -static inline void snd_card_dummy_pcm_timer_stop(struct snd_dummy_pcm *dpcm) -{ - del_timer(&dpcm->timer); -} - -static int snd_card_dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd) +static int dummy_systimer_stop(struct snd_pcm_substream *substream) { - struct snd_pcm_runtime *runtime = substream->runtime; - struct snd_dummy_pcm *dpcm = runtime->private_data; - int err = 0; - + struct dummy_systimer_pcm *dpcm = substream->runtime->private_data; spin_lock(&dpcm->lock); - switch (cmd) { - case SNDRV_PCM_TRIGGER_START: - case SNDRV_PCM_TRIGGER_RESUME: - snd_card_dummy_pcm_timer_start(dpcm); - break; - case SNDRV_PCM_TRIGGER_STOP: - case SNDRV_PCM_TRIGGER_SUSPEND: - snd_card_dummy_pcm_timer_stop(dpcm); - break; - default: - err = -EINVAL; - break; - } + del_timer(&dpcm->timer); spin_unlock(&dpcm->lock); return 0; } -static int snd_card_dummy_pcm_prepare(struct snd_pcm_substream *substream) +static int dummy_systimer_prepare(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; - struct snd_dummy_pcm *dpcm = runtime->private_data; + struct dummy_systimer_pcm *dpcm = runtime->private_data; int bps; bps = snd_pcm_format_width(runtime->format) * runtime->rate * @@ -247,15 +252,12 @@ static int snd_card_dummy_pcm_prepare(struct snd_pcm_substream *substream) dpcm->pcm_irq_pos = 0; dpcm->pcm_buf_pos = 0; - snd_pcm_format_set_silence(runtime->format, runtime->dma_area, - bytes_to_samples(runtime, runtime->dma_bytes)); - return 0; } -static void snd_card_dummy_pcm_timer_function(unsigned long data) +static void dummy_systimer_callback(unsigned long data) { - struct snd_dummy_pcm *dpcm = (struct snd_dummy_pcm *)data; + struct dummy_systimer_pcm *dpcm = (struct dummy_systimer_pcm *)data; unsigned long flags; spin_lock_irqsave(&dpcm->lock, flags); @@ -272,36 +274,212 @@ static void snd_card_dummy_pcm_timer_function(unsigned long data) spin_unlock_irqrestore(&dpcm->lock, flags); } -static snd_pcm_uframes_t snd_card_dummy_pcm_pointer(struct snd_pcm_substream *substream) +static snd_pcm_uframes_t +dummy_systimer_pointer(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; - struct snd_dummy_pcm *dpcm = runtime->private_data; + struct dummy_systimer_pcm *dpcm = runtime->private_data; return bytes_to_frames(runtime, dpcm->pcm_buf_pos / dpcm->pcm_hz); } -static struct snd_pcm_hardware snd_card_dummy_playback = +static int dummy_systimer_create(struct snd_pcm_substream *substream) { - .info = (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED | - SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_MMAP_VALID), - .formats = USE_FORMATS, - .rates = USE_RATE, - .rate_min = USE_RATE_MIN, - .rate_max = USE_RATE_MAX, - .channels_min = USE_CHANNELS_MIN, - .channels_max = USE_CHANNELS_MAX, - .buffer_bytes_max = MAX_BUFFER_SIZE, - .period_bytes_min = 64, - .period_bytes_max = MAX_PERIOD_SIZE, - .periods_min = USE_PERIODS_MIN, - .periods_max = USE_PERIODS_MAX, - .fifo_size = 0, + struct dummy_systimer_pcm *dpcm; + + dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL); + if (!dpcm) + return -ENOMEM; + substream->runtime->private_data = dpcm; + init_timer(&dpcm->timer); + dpcm->timer.data = (unsigned long) dpcm; + dpcm->timer.function = dummy_systimer_callback; + spin_lock_init(&dpcm->lock); + dpcm->substream = substream; + return 0; +} + +static void dummy_systimer_free(struct snd_pcm_substream *substream) +{ + kfree(substream->runtime->private_data); +} + +static struct dummy_timer_ops dummy_systimer_ops = { + .create = dummy_systimer_create, + .free = dummy_systimer_free, + .prepare = dummy_systimer_prepare, + .start = dummy_systimer_start, + .stop = dummy_systimer_stop, + .pointer = dummy_systimer_pointer, +}; + +#ifdef CONFIG_HIGH_RES_TIMERS +/* + * hrtimer interface + */ + +struct dummy_hrtimer_pcm { + ktime_t base_time; + ktime_t period_time; + atomic_t running; + struct hrtimer timer; + struct tasklet_struct tasklet; + struct snd_pcm_substream *substream; +}; + +static void dummy_hrtimer_pcm_elapsed(unsigned long priv) +{ + struct dummy_hrtimer_pcm *dpcm = (struct dummy_hrtimer_pcm *)priv; + if (atomic_read(&dpcm->running)) + snd_pcm_period_elapsed(dpcm->substream); +} + +static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer) +{ + struct dummy_hrtimer_pcm *dpcm; + + dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer); + if (!atomic_read(&dpcm->running)) + return HRTIMER_NORESTART; + tasklet_schedule(&dpcm->tasklet); + hrtimer_forward_now(timer, dpcm->period_time); + return HRTIMER_RESTART; +} + +static int dummy_hrtimer_start(struct snd_pcm_substream *substream) +{ + struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data; + + dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer); + hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL); + atomic_set(&dpcm->running, 1); + return 0; +} + +static int dummy_hrtimer_stop(struct snd_pcm_substream *substream) +{ + struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data; + + atomic_set(&dpcm->running, 0); + hrtimer_cancel(&dpcm->timer); + return 0; +} + +static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm) +{ + tasklet_kill(&dpcm->tasklet); +} + +static snd_pcm_uframes_t +dummy_hrtimer_pointer(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct dummy_hrtimer_pcm *dpcm = runtime->private_data; + u64 delta; + u32 pos; + + delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer), + dpcm->base_time); + delta = div_u64(delta * runtime->rate + 999999, 1000000); + div_u64_rem(delta, runtime->buffer_size, &pos); + return pos; +} + +static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct dummy_hrtimer_pcm *dpcm = runtime->private_data; + unsigned int period, rate; + long sec; + unsigned long nsecs; + + dummy_hrtimer_sync(dpcm); + period = runtime->period_size; + rate = runtime->rate; + sec = period / rate; + period %= rate; + nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate); + dpcm->period_time = ktime_set(sec, nsecs); + + return 0; +} + +static int dummy_hrtimer_create(struct snd_pcm_substream *substream) +{ + struct dummy_hrtimer_pcm *dpcm; + + dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL); + if (!dpcm) + return -ENOMEM; + substream->runtime->private_data = dpcm; + hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + dpcm->timer.function = dummy_hrtimer_callback; + dpcm->substream = substream; + atomic_set(&dpcm->running, 0); + tasklet_init(&dpcm->tasklet, dummy_hrtimer_pcm_elapsed, + (unsigned long)dpcm); + return 0; +} + +static void dummy_hrtimer_free(struct snd_pcm_substream *substream) +{ + struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data; + dummy_hrtimer_sync(dpcm); + kfree(dpcm); +} + +static struct dummy_timer_ops dummy_hrtimer_ops = { + .create = dummy_hrtimer_create, + .free = dummy_hrtimer_free, + .prepare = dummy_hrtimer_prepare, + .start = dummy_hrtimer_start, + .stop = dummy_hrtimer_stop, + .pointer = dummy_hrtimer_pointer, }; -static struct snd_pcm_hardware snd_card_dummy_capture = +#endif /* CONFIG_HIGH_RES_TIMERS */ + +/* + * PCM interface + */ + +static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd) +{ + struct snd_dummy *dummy = snd_pcm_substream_chip(substream); + + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_RESUME: + return dummy->timer_ops->start(substream); + case SNDRV_PCM_TRIGGER_STOP: + case SNDRV_PCM_TRIGGER_SUSPEND: + return dummy->timer_ops->stop(substream); + } + return -EINVAL; +} + +static int dummy_pcm_prepare(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct snd_dummy *dummy = snd_pcm_substream_chip(substream); + + snd_pcm_format_set_silence(runtime->format, runtime->dma_area, + bytes_to_samples(runtime, runtime->dma_bytes)); + return dummy->timer_ops->prepare(substream); +} + +static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream) { - .info = (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED | - SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_MMAP_VALID), + struct snd_dummy *dummy = snd_pcm_substream_chip(substream); + + return dummy->timer_ops->pointer(substream); +} + +static struct snd_pcm_hardware dummy_pcm_hardware = { + .info = (SNDRV_PCM_INFO_MMAP | + SNDRV_PCM_INFO_INTERLEAVED | + SNDRV_PCM_INFO_RESUME | + SNDRV_PCM_INFO_MMAP_VALID), .formats = USE_FORMATS, .rates = USE_RATE, .rate_min = USE_RATE_MIN, @@ -316,117 +494,70 @@ static struct snd_pcm_hardware snd_card_dummy_capture = .fifo_size = 0, }; -static void snd_card_dummy_runtime_free(struct snd_pcm_runtime *runtime) -{ - kfree(runtime->private_data); -} - -static int snd_card_dummy_hw_params(struct snd_pcm_substream *substream, - struct snd_pcm_hw_params *hw_params) +static int dummy_pcm_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *hw_params) { - return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params)); + return snd_pcm_lib_malloc_pages(substream, + params_buffer_bytes(hw_params)); } -static int snd_card_dummy_hw_free(struct snd_pcm_substream *substream) +static int dummy_pcm_hw_free(struct snd_pcm_substream *substream) { return snd_pcm_lib_free_pages(substream); } -static struct snd_dummy_pcm *new_pcm_stream(struct snd_pcm_substream *substream) -{ - struct snd_dummy_pcm *dpcm; - - dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL); - if (! dpcm) - return dpcm; - init_timer(&dpcm->timer); - dpcm->timer.data = (unsigned long) dpcm; - dpcm->timer.function = snd_card_dummy_pcm_timer_function; - spin_lock_init(&dpcm->lock); - dpcm->substream = substream; - return dpcm; -} - -static int snd_card_dummy_playback_open(struct snd_pcm_substream *substream) +static int dummy_pcm_open(struct snd_pcm_substream *substream) { + struct snd_dummy *dummy = snd_pcm_substream_chip(substream); struct snd_pcm_runtime *runtime = substream->runtime; - struct snd_dummy_pcm *dpcm; int err; - if ((dpcm = new_pcm_stream(substream)) == NULL) - return -ENOMEM; - runtime->private_data = dpcm; - /* makes the infrastructure responsible for freeing dpcm */ - runtime->private_free = snd_card_dummy_runtime_free; - runtime->hw = snd_card_dummy_playback; - if (substream->pcm->device & 1) { - runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED; - runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED; - } - if (substream->pcm->device & 2) - runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID); - err = add_playback_constraints(runtime); + dummy->timer_ops = &dummy_systimer_ops; +#ifdef CONFIG_HIGH_RES_TIMERS + if (hrtimer) + dummy->timer_ops = &dummy_hrtimer_ops; +#endif + + err = dummy->timer_ops->create(substream); if (err < 0) return err; - return 0; -} - -static int snd_card_dummy_capture_open(struct snd_pcm_substream *substream) -{ - struct snd_pcm_runtime *runtime = substream->runtime; - struct snd_dummy_pcm *dpcm; - int err; - - if ((dpcm = new_pcm_stream(substream)) == NULL) - return -ENOMEM; - runtime->private_data = dpcm; - /* makes the infrastructure responsible for freeing dpcm */ - runtime->private_free = snd_card_dummy_runtime_free; - runtime->hw = snd_card_dummy_capture; - if (substream->pcm->device == 1) { + runtime->hw = dummy_pcm_hardware; + if (substream->pcm->device & 1) { runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED; runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED; } if (substream->pcm->device & 2) - runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID); - err = add_capture_constraints(runtime); - if (err < 0) + runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP | + SNDRV_PCM_INFO_MMAP_VALID); + + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + err = add_playback_constraints(substream->runtime); + else + err = add_capture_constraints(substream->runtime); + if (err < 0) { + dummy->timer_ops->free(substream); return err; - - return 0; -} - -static int snd_card_dummy_playback_close(struct snd_pcm_substream *substream) -{ + } return 0; } -static int snd_card_dummy_capture_close(struct snd_pcm_substream *substream) +static int dummy_pcm_close(struct snd_pcm_substream *substream) { + struct snd_dummy *dummy = snd_pcm_substream_chip(substream); + dummy->timer_ops->free(substream); return 0; } -static struct snd_pcm_ops snd_card_dummy_playback_ops = { - .open = snd_card_dummy_playback_open, - .close = snd_card_dummy_playback_close, - .ioctl = snd_pcm_lib_ioctl, - .hw_params = snd_card_dummy_hw_params, - .hw_free = snd_card_dummy_hw_free, - .prepare = snd_card_dummy_pcm_prepare, - .trigger = snd_card_dummy_pcm_trigger, - .pointer = snd_card_dummy_pcm_pointer, -}; - -static struct snd_pcm_ops snd_card_dummy_capture_ops = { - .open = snd_card_dummy_capture_open, - .close = snd_card_dummy_capture_close, - .ioctl = snd_pcm_lib_ioctl, - .hw_params = snd_card_dummy_hw_params, - .hw_free = snd_card_dummy_hw_free, - .prepare = snd_card_dummy_pcm_prepare, - .trigger = snd_card_dummy_pcm_trigger, - .pointer = snd_card_dummy_pcm_pointer, +static struct snd_pcm_ops dummy_pcm_ops = { + .open = dummy_pcm_open, + .close = dummy_pcm_close, + .ioctl = snd_pcm_lib_ioctl, + .hw_params = dummy_pcm_hw_params, + .hw_free = dummy_pcm_hw_free, + .prepare = dummy_pcm_prepare, + .trigger = dummy_pcm_trigger, + .pointer = dummy_pcm_pointer, }; static int __devinit snd_card_dummy_pcm(struct snd_dummy *dummy, int device, @@ -440,8 +571,8 @@ static int __devinit snd_card_dummy_pcm(struct snd_dummy *dummy, int device, if (err < 0) return err; dummy->pcm = pcm; - snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_card_dummy_playback_ops); - snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_card_dummy_capture_ops); + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &dummy_pcm_ops); + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &dummy_pcm_ops); pcm->private_data = dummy; pcm->info_flags = 0; strcpy(pcm->name, "Dummy PCM"); -- 2.30.2