On Mon, Sep 28, 2015 at 11:01:34AM +0200, Arnaud Pouliquen wrote:
few questions/remarks BR, Arnaud
+static void hdmi_codec_abort(struct device *dev) +{
- struct hdmi_codec_priv *hcp = dev_get_drvdata(dev);
- dev_dbg(dev, "%s()\n", __func__);
- mutex_lock(&hcp->current_stream_lock);
- if (hcp->current_stream && hcp->current_stream->runtime &&
snd_pcm_running(hcp->current_stream)) {dev_info(dev, "HDMI audio playback aborted\n");snd_pcm_stream_lock_irq(hcp->current_stream);snd_pcm_stop(hcp->current_stream, SNDRV_PCM_STATE_DISCONNECTED);snd_pcm_stream_unlock_irq(hcp->current_stream);- }
- mutex_unlock(&hcp->current_stream_lock);
+}
Does driver should stop the stream in case of unplug? This could generate unexpected behavior at application level. Perhaps should be better if this part is managed in DRM driver. if HDMI master, I2S bus should be maintained ON to consume the audio stream until application action.
If it does, that's really horrid.
Firstly, do you expect your video playback to stop just because you've unplugged the TV? Maybe you've got a dumb HDMI switch, and you've switched from one input to another to momentarily check something on another input - should the video playback suddenly end up with its audio path being dumped on the floor because of that?
Also, as I've said before, there's hardware out there where the SPDIF audio output is routed to more than just the HDMI interface, and the capabilities of HDMI really don't apply in that situation - you may have an AV receiver connected to the SPDIF output which is able to accept much more than the basic audio that most TVs accept. Having stuff restricted to the union of the abilities is far too restrictive. Stopping the audio output because the TV went away in this case is also plain idiotic.
SPDIF is something that can be routed to multiple devices simultaneously, and there's no capability or connection reporting involved in it. Imposing the status of one "SPDIF listener" on the entire audio system is unreasonable.
+static int hdmi_codec_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,struct snd_soc_dai *dai)+{
- struct hdmi_codec_priv *hcp = snd_soc_dai_get_drvdata(dai);
- struct hdmi_codec_params hp = {
.iec = {.status = { 0 },.subcode = { 0 },.pad = 0,.dig_subframe = { 0 },}- };
- int ret;
- dev_dbg(dai->dev, "%s() width %d rate %d channels %d\n", __func__,
params_width(params), params_rate(params),params_channels(params));- ret = snd_pcm_create_iec958_consumer_hw_params(params, hp.iec.status,
sizeof(hp.iec.status));Tell me if i am wrong, but in case of SPDIF format, IEC status is managed by cpu_dai not by the codec.
Correct. I2S needs the IEC958 status programmed into the HDMI interface though, because HDMI is basically SPDIF.