ASoC: Intel: avs: Update stream status in a separate thread

Function snd_pcm_period_elapsed() is part of sequence servicing HDAudio
stream IRQs. It's called under Global Interrupt Enable (GIE) disabled -
no HDAudio interrupts will be raised. At the same time, the function may
end up calling __snd_pcm_xrun() or snd_pcm_drain_done(). On the
avs-driver side, this translates to IPCs and as GIE is disabled, these
will never complete successfully.

Improve system stability by scheduling stream-IRQ handling in a separate
thread.

Signed-off-by: Amadeusz Sławiński <[email protected]>
Reviewed-by: Cezary Rojewski <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>

Author: Amadeusz Sławiński

sound/soc/intel/avs/core.c

@@ -28,6 +28,7 @@
 #include "avs.h"
 #include "cldma.h"
 #include "messages.h"
+#include "pcm.h"
 
 static u32 pgctl_mask = AZX_PGCTL_LSRMD_MASK;
 module_param(pgctl_mask, uint, 0444);
@@ -247,7 +248,7 @@ static void hdac_stream_update_pos(struct hdac_stream *stream, u64 buffer_size)
 static void hdac_update_stream(struct hdac_bus *bus, struct hdac_stream *stream)
 {
 	if (stream->substream) {
-		snd_pcm_period_elapsed(stream->substream);
+		avs_period_elapsed(stream->substream);
 	} else if (stream->cstream) {
 		u64 buffer_size = stream->cstream->runtime->buffer_size;
 

sound/soc/intel/avs/pcm.c

@@ -16,6 +16,7 @@
 #include <sound/soc-component.h>
 #include "avs.h"
 #include "path.h"
+#include "pcm.h"
 #include "topology.h"
 #include "../../codecs/hda.h"
 
@@ -30,6 +31,7 @@ struct avs_dma_data {
 		struct hdac_ext_stream *host_stream;
 	};
 
+	struct work_struct period_elapsed_work;
 	struct snd_pcm_substream *substream;
 };
 
@@ -56,6 +58,22 @@ avs_dai_find_path_template(struct snd_soc_dai *dai, bool is_fe, int direction)
 	return dw->priv;
 }
 
+static void avs_period_elapsed_work(struct work_struct *work)
+{
+	struct avs_dma_data *data = container_of(work, struct avs_dma_data, period_elapsed_work);
+
+	snd_pcm_period_elapsed(data->substream);
+}
+
+void avs_period_elapsed(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
+	struct snd_soc_dai *dai = snd_soc_rtd_to_cpu(rtd, 0);
+	struct avs_dma_data *data = snd_soc_dai_get_dma_data(dai, substream);
+
+	schedule_work(&data->period_elapsed_work);
+}
+
 static int avs_dai_startup(struct snd_pcm_substream *substream, struct snd_soc_dai *dai)
 {
 	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
@@ -77,6 +95,7 @@ static int avs_dai_startup(struct snd_pcm_substream *substream, struct snd_soc_d
 	data->substream = substream;
 	data->template = template;
 	data->adev = adev;
+	INIT_WORK(&data->period_elapsed_work, avs_period_elapsed_work);
 	snd_soc_dai_set_dma_data(dai, substream, data);
 
 	if (rtd->dai_link->ignore_suspend)

sound/soc/intel/avs/pcm.h

@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright(c) 2024 Intel Corporation
+ *
+ * Authors: Cezary Rojewski <[email protected]>
+ *          Amadeusz Slawinski <[email protected]>
+ */
+
+#ifndef __SOUND_SOC_INTEL_AVS_PCM_H
+#define __SOUND_SOC_INTEL_AVS_PCM_H
+
+#include <sound/pcm.h>
+
+void avs_period_elapsed(struct snd_pcm_substream *substream);
+
+#endif