From 6fd1b9225de1b09cd8dd79e1ccba8d84b4e94036 Mon Sep 17 00:00:00 2001 From: Andrey Golovko Date: Thu, 13 Aug 2026 19:40:00 +0300 Subject: [PATCH] ASoC: sdw_utils: prepare the stream again when resuming A peripheral loses its Data Port configuration when the controller is power-gated during system suspend, so the ports have to be prepared again before the stream can be enabled. That happens on its own when userspace calls snd_pcm_prepare() after SNDRV_PCM_STATE_SUSPENDED, but an application is also allowed to restart the stream with SNDRV_PCM_IOCTL_RESUME on a card that advertises SNDRV_PCM_INFO_RESUME, as the AMD ACP platforms do. That path only reaches the trigger callback, sdw_enable_stream() writes the channels of ports that were never prepared, and playback silently produces nothing: the PCM keeps running, no error is reported anywhere, and the speakers stay quiet until the stream is torn down and set up again. Prepare the stream on SNDRV_PCM_TRIGGER_RESUME, before enabling it. The SoundWire core expects exactly this: sdw_prepare_stream() accepts a disabled stream and then reapplies the bus parameters without recomputing them, which it documents as the resume case. Signed-off-by: Andrey Golovko Link: https://patch.msgid.link/20260813194000.10412-2-andrey.golovko@gmail.com Signed-off-by: Mark Brown --- sound/soc/sdw_utils/soc_sdw_utils.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/sound/soc/sdw_utils/soc_sdw_utils.c b/sound/soc/sdw_utils/soc_sdw_utils.c index 8a07ba2a29e5a..3e091e78d8c25 100644 --- a/sound/soc/sdw_utils/soc_sdw_utils.c +++ b/sound/soc/sdw_utils/soc_sdw_utils.c @@ -1510,9 +1510,24 @@ int asoc_sdw_trigger(struct snd_pcm_substream *substream, int cmd) } switch (cmd) { + case SNDRV_PCM_TRIGGER_RESUME: + /* + * The peripherals lose their port configuration when the + * controller is power-gated during system suspend, and an + * application that restarts the stream with + * SNDRV_PCM_IOCTL_RESUME - which platforms advertising + * SNDRV_PCM_INFO_RESUME allow - never goes through + * .prepare() again. Prepare the stream here so that the + * ports are reprogrammed before they are enabled; + * sdw_prepare_stream() reapplies the parameters without + * recomputing them when the stream is disabled. + */ + ret = sdw_prepare_stream(sdw_stream); + if (ret) + break; + fallthrough; case SNDRV_PCM_TRIGGER_START: case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: - case SNDRV_PCM_TRIGGER_RESUME: ret = sdw_enable_stream(sdw_stream); break; -- 2.53.0