ALSA: pcm: Introduce protocol version field to sw_params
For controlling the new fields more strictly, add sw_params.proto
field indicating the protocol version of the user-space. User-space
should fill the SNDRV_PCM_VERSION value it's built with, then kernel
can know whether the new fields should be evaluated or not.
And now tstamp_type field is evaluated only when the valid value is
set there. This avoids the wrong override of tstamp_type to zero,
which is SNDRV_PCM_TSTAMP_TYPE_GETTIMEOFDAY.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 81dedc3..8cd2f93 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -543,7 +543,8 @@
if (params->tstamp_mode > SNDRV_PCM_TSTAMP_LAST)
return -EINVAL;
- if (params->tstamp_type > SNDRV_PCM_TSTAMP_TYPE_LAST)
+ if (params->proto >= SNDRV_PROTOCOL_VERSION(2, 0, 12) &&
+ params->tstamp_type > SNDRV_PCM_TSTAMP_TYPE_LAST)
return -EINVAL;
if (params->avail_min == 0)
return -EINVAL;
@@ -559,7 +560,8 @@
err = 0;
snd_pcm_stream_lock_irq(substream);
runtime->tstamp_mode = params->tstamp_mode;
- runtime->tstamp_type = params->tstamp_type;
+ if (params->proto >= SNDRV_PROTOCOL_VERSION(2, 0, 12))
+ runtime->tstamp_type = params->tstamp_type;
runtime->period_step = params->period_step;
runtime->control->avail_min = params->avail_min;
runtime->start_threshold = params->start_threshold;