@@ -711,6 +711,24 @@ static int configure_endpoint(struct snd_usb_substream *subs)
return ret;
}
+static int snd_usb_pcm_change_state(struct snd_usb_substream *subs, int state)
+{
+ int ret;
+
+ if (!subs->str_pd)
+ return 0;
+
+ ret = snd_usb_power_domain_set(subs->stream->chip, subs->str_pd, state);
+ if (ret < 0) {
+ dev_err(&subs->dev->dev,
+ "Cannot change Power Domain ID: %d to state: %d. Err: %d\n",
+ subs->str_pd->pd_id, state, ret);
+ return ret;
+ }
+
+ return 0;
+}
+
/*
* hw_params callback
*
@@ -755,16 +773,22 @@ static int snd_usb_hw_params(struct snd_pcm_substream *substream,
ret = snd_usb_lock_shutdown(subs->stream->chip);
if (ret < 0)
return ret;
+
ret = set_format(subs, fmt);
- snd_usb_unlock_shutdown(subs->stream->chip);
if (ret < 0)
- return ret;
+ goto unlock;
+
+ ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D0);
+ if (ret < 0)
+ goto unlock;
subs->interface = fmt->iface;
subs->altset_idx = fmt->altset_idx;
subs->need_setup_ep = true;
- return 0;
+ unlock:
+ snd_usb_unlock_shutdown(subs->stream->chip);
+ return ret;
}
/*
@@ -1265,6 +1289,7 @@ static int snd_usb_pcm_close(struct snd_pcm_substream *substream)
int direction = substream->stream;
struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
struct snd_usb_substream *subs = &as->substream[direction];
+ int ret;
stop_endpoints(subs, true);
@@ -1273,7 +1298,10 @@ static int snd_usb_pcm_close(struct snd_pcm_substream *substream)
!snd_usb_lock_shutdown(subs->stream->chip)) {
usb_set_interface(subs->dev, subs->interface, 0);
subs->interface = -1;
+ ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D1);
snd_usb_unlock_shutdown(subs->stream->chip);
+ if (ret < 0)
+ return ret;
}
subs->pcm_substream = NULL;
@@ -110,8 +110,12 @@ static void snd_usb_init_substream(struct snd_usb_stream *as,
if (fp->channels > subs->channels_max)
subs->channels_max = fp->channels;
- if (pd)
+ if (pd) {
subs->str_pd = pd;
+ /* Initialize Power Domain to idle status D1 */
+ snd_usb_power_domain_set(subs->stream->chip, pd,
+ UAC3_PD_STATE_D1);
+ }
snd_usb_preallocate_buffer(subs);
}
Make use of UAC3 Power Domains associated to an Audio Streaming path within the PCM's logic. This means, when there is no audio being transferred (pcm is closed), the host will set the Power Domain associated to that substream to state D1. When audio is being transferred (from hw_params onwards), the Power Domain will be set to D0 state. This is the way the host lets the device now which Terminal is going to be actively used and it is for the device to manage its own internal resources on that UAC3 Power Domain. Signed-off-by: Jorge Sanjuan <jorge.sanjuan@codethink.co.uk> --- sound/usb/pcm.c | 34 +++++++++++++++++++++++++++++++--- sound/usb/stream.c | 6 +++++- 2 files changed, 36 insertions(+), 4 deletions(-)