diff options
Diffstat (limited to 'sound/pci/hda/hda_intel.c')
| -rw-r--r-- | sound/pci/hda/hda_intel.c | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c index 8fd250d8ed7..d96a14e1fa9 100644 --- a/sound/pci/hda/hda_intel.c +++ b/sound/pci/hda/hda_intel.c @@ -47,6 +47,9 @@ #include <linux/reboot.h> #include <linux/io.h> #include <linux/pm_runtime.h> +#include <linux/clocksource.h> +#include <linux/time.h> + #ifdef CONFIG_X86 /* for snoop control */ #include <asm/pgtable.h> @@ -419,6 +422,9 @@ struct azx_dev { unsigned int insufficient :1; unsigned int wc_marked:1; unsigned int no_period_wakeup:1; + + struct timecounter azx_tc; + struct cyclecounter azx_cc; }; /* CORB/RIRB */ @@ -1749,6 +1755,64 @@ static inline void azx_release_device(struct azx_dev *azx_dev) azx_dev->opened = 0; } +static cycle_t azx_cc_read(const struct cyclecounter *cc) +{ + struct azx_dev *azx_dev = container_of(cc, struct azx_dev, azx_cc); + struct snd_pcm_substream *substream = azx_dev->substream; + struct azx_pcm *apcm = snd_pcm_substream_chip(substream); + struct azx *chip = apcm->chip; + + return azx_readl(chip, WALLCLK); +} + +static void azx_timecounter_init(struct snd_pcm_substream *substream, + bool force, cycle_t last) +{ + struct azx_dev *azx_dev = get_azx_dev(substream); + struct timecounter *tc = &azx_dev->azx_tc; + struct cyclecounter *cc = &azx_dev->azx_cc; + u64 nsec; + + cc->read = azx_cc_read; + cc->mask = CLOCKSOURCE_MASK(32); + + /* + * Converting from 24 MHz to ns means applying a 125/3 factor. + * To avoid any saturation issues in intermediate operations, + * the 125 factor is applied first. The division is applied + * last after reading the timecounter value. + * Applying the 1/3 factor as part of the multiplication + * requires at least 20 bits for a decent precision, however + * overflows occur after about 4 hours or less, not a option. + */ + + cc->mult = 125; /* saturation after 195 years */ + cc->shift = 0; + + nsec = 0; /* audio time is elapsed time since trigger */ + timecounter_init(tc, cc, nsec); + if (force) + /* + * force timecounter to use predefined value, + * used for synchronized starts + */ + tc->cycle_last = last; +} + +static int azx_get_wallclock_tstamp(struct snd_pcm_substream *substream, + struct timespec *ts) +{ + struct azx_dev *azx_dev = get_azx_dev(substream); + u64 nsec; + + nsec = timecounter_read(&azx_dev->azx_tc); + nsec = div_u64(nsec, 3); /* can be optimized */ + + *ts = ns_to_timespec(nsec); + + return 0; +} + static struct snd_pcm_hardware azx_pcm_hw = { .info = (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED | @@ -1758,6 +1822,7 @@ static struct snd_pcm_hardware azx_pcm_hw = { /* SNDRV_PCM_INFO_RESUME |*/ SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_SYNC_START | + SNDRV_PCM_INFO_HAS_WALL_CLOCK | SNDRV_PCM_INFO_NO_PERIOD_WAKEUP), .formats = SNDRV_PCM_FMTBIT_S16_LE, .rates = SNDRV_PCM_RATE_48000, @@ -1797,6 +1862,12 @@ static int azx_pcm_open(struct snd_pcm_substream *substream) runtime->hw.rates = hinfo->rates; snd_pcm_limit_hw_rates(runtime); snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS); + + /* avoid wrap-around with wall-clock */ + snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_TIME, + 20, + 178000000); + if (chip->align_buffer_size) /* constrain buffer sizes to be multiple of 128 bytes. This is more efficient in terms of memory @@ -1836,6 +1907,12 @@ static int azx_pcm_open(struct snd_pcm_substream *substream) mutex_unlock(&chip->open_mutex); return -EINVAL; } + + /* disable WALLCLOCK timestamps for capture streams + until we figure out how to handle digital inputs */ + if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) + runtime->hw.info &= ~SNDRV_PCM_INFO_HAS_WALL_CLOCK; + spin_lock_irqsave(&chip->reg_lock, flags); azx_dev->substream = substream; azx_dev->running = 0; @@ -2072,6 +2149,22 @@ static int azx_pcm_trigger(struct snd_pcm_substream *substream, int cmd) azx_readl(chip, OLD_SSYNC) & ~sbits); else azx_writel(chip, SSYNC, azx_readl(chip, SSYNC) & ~sbits); + if (start) { + azx_timecounter_init(substream, 0, 0); + if (nsync > 1) { + cycle_t cycle_last; + + /* same start cycle for master and group */ + azx_dev = get_azx_dev(substream); + cycle_last = azx_dev->azx_tc.cycle_last; + + snd_pcm_group_for_each_entry(s, substream) { + if (s->pcm->card != substream->pcm->card) + continue; + azx_timecounter_init(s, 1, cycle_last); + } + } + } spin_unlock(&chip->reg_lock); return 0; } @@ -2306,6 +2399,7 @@ static struct snd_pcm_ops azx_pcm_ops = { .prepare = azx_pcm_prepare, .trigger = azx_pcm_trigger, .pointer = azx_pcm_pointer, + .wall_clock = azx_get_wallclock_tstamp, .mmap = azx_pcm_mmap, .page = snd_pcm_sgbuf_ops_page, }; |