ALSA: Fix invalid jiffies check after pause

The hw_ptr_jiffies has to be reset properly to avoid the invalid
check of jiffies delta in snd_pcm_update_hw_ptr*() functions.
Especailly this patch fixes the bogus jiffies check after the puase
and resume.

This patch is a modified version of the original patch by Jaroslav.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index a2a792c..3eea98a 100644 (file)
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -1478,7 +1478,6 @@ static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
                runtime->status->hw_ptr %= runtime->buffer_size;
        else
                runtime->status->hw_ptr = 0;
-       runtime->hw_ptr_jiffies = jiffies;
        snd_pcm_stream_unlock_irqrestore(substream, flags);
        return 0;
 }

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index fc6f98e..b5da656 100644 (file)
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -848,6 +848,7 @@ static void snd_pcm_post_start(struct snd_pcm_substream *substream, int state)
 {
        struct snd_pcm_runtime *runtime = substream->runtime;
        snd_pcm_trigger_tstamp(substream);
+       runtime->hw_ptr_jiffies = jiffies;
        runtime->status->state = state;
        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
            runtime->silence_size > 0)
@@ -961,6 +962,11 @@ static int snd_pcm_do_pause(struct snd_pcm_substream *substream, int push)
 {
        if (substream->runtime->trigger_master != substream)
                return 0;
+       /* The jiffies check in snd_pcm_update_hw_ptr*() is done by
+        * a delta betwen the current jiffies, this gives a large enough
+        * delta, effectively to skip the check once.
+        */
+       substream->runtime->hw_ptr_jiffies = jiffies - HZ * 1000;
        return substream->ops->trigger(substream,
                                       push ? SNDRV_PCM_TRIGGER_PAUSE_PUSH :
                                              SNDRV_PCM_TRIGGER_PAUSE_RELEASE);