From 232892fb14265b07b7a50061f36aaa5a6b81fb9d Mon Sep 17 00:00:00 2001 From: Jerome Anand Date: Wed, 25 Jan 2017 04:27:53 +0530 Subject: [PATCH] ALSA: x86: hdmi: continue playback even when display resolution changes When the display resolution changes, the drm disables the display pipes due to which audio rendering stops. At this time, we need to ensure the existing audio pointers and buffers are cleared out so that the playback can restarted once the display pipe is enabled with a different N/CTS values Signed-off-by: Pierre-Louis Bossart Signed-off-by: Jerome Anand Signed-off-by: Takashi Iwai --- sound/x86/intel_hdmi_audio.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/sound/x86/intel_hdmi_audio.c b/sound/x86/intel_hdmi_audio.c index b69521aa2ed1..f30155446117 100644 --- a/sound/x86/intel_hdmi_audio.c +++ b/sound/x86/intel_hdmi_audio.c @@ -43,6 +43,7 @@ static DEFINE_MUTEX(had_mutex); static int hdmi_card_index = SNDRV_DEFAULT_IDX1; static char *hdmi_card_id = SNDRV_DEFAULT_STR1; static struct snd_intelhad *had_data; +static int underrun_count; module_param_named(index, hdmi_card_index, int, 0444); MODULE_PARM_DESC(index, @@ -1052,6 +1053,7 @@ static int snd_intelhad_open(struct snd_pcm_substream *substream) intelhaddata = snd_pcm_substream_chip(substream); had_stream = intelhaddata->private_data; runtime = substream->runtime; + underrun_count = 0; pm_runtime_get(intelhaddata->dev); @@ -1445,10 +1447,23 @@ static snd_pcm_uframes_t snd_intelhad_pcm_pointer( buf_id = intelhaddata->curr_buf % 4; had_read_register(AUD_BUF_A_LENGTH + (buf_id * HAD_REG_WIDTH), &t); - if (t == 0) { - pr_debug("discovered buffer done for buf %d\n", buf_id); - /* had_process_buffer_done(intelhaddata); */ + + if ((t == 0) || (t == ((u32)-1L))) { + underrun_count++; + pr_debug("discovered buffer done for buf %d, count = %d\n", + buf_id, underrun_count); + + if (underrun_count > (HAD_MIN_PERIODS/2)) { + pr_debug("assume audio_codec_reset, underrun = %d - do xrun\n", + underrun_count); + underrun_count = 0; + return SNDRV_PCM_POS_XRUN; + } + } else { + /* Reset Counter */ + underrun_count = 0; } + t = intelhaddata->buf_info[buf_id].buf_size - t; if (intelhaddata->stream_info.buffer_rendered) -- 2.20.1