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Date:   Thu,  8 Jul 2021 02:08:15 +0000
Message-Id: <20210708020815.3489365-1-lerobert@google.com>
Mime-Version: 1.0
Subject: [Patch v2] ALSA: compress: allow to leave draining state when pausing
 in draining
From:   Robert Lee <lerobert@google.com>
To:     vkoul@kernel.org, perex@perex.cz, tiwai@suse.com
Cc:     alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org,
        carterhsu@google.com, zxinhui@google.com, bubblefang@google.com,
        Robert Lee <lerobert@google.com>
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Precedence: bulk

When compress offload pauses in draining state, not all platforms
need to keep in draining state. Some platforms may call drain or
partial drain again when resume from pause in draining, so it needs
to wake up from snd_compress_wait_for_drain() in this case.

Call API snd_compr_leave_draining_in_pause(), if the platform
doesn't need to keep in draining state when pause in draining
state.

Signed-off-by: Robert Lee <lerobert@google.com>
---
 include/sound/compress_driver.h | 14 ++++++++++++++
 sound/core/compress_offload.c   |  8 +++++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/include/sound/compress_driver.h b/include/sound/compress_driver.h
index 277087f635f3..e16524a93a14 100644
--- a/include/sound/compress_driver.h
+++ b/include/sound/compress_driver.h
@@ -145,6 +145,7 @@ struct snd_compr_ops {
  * @lock: device lock
  * @device: device id
  * @use_pause_in_draining: allow pause in draining, true when set
+ * @leave_draining_in_pause: leave draining state when pausing in draining
  */
 struct snd_compr {
 	const char *name;
@@ -156,6 +157,7 @@ struct snd_compr {
 	struct mutex lock;
 	int device;
 	bool use_pause_in_draining;
+	bool leave_draining_in_pause;
 #ifdef CONFIG_SND_VERBOSE_PROCFS
 	/* private: */
 	char id[64];
@@ -182,6 +184,18 @@ static inline void snd_compr_use_pause_in_draining(struct snd_compr_stream *subs
 	substream->device->use_pause_in_draining = true;
 }
 
+/**
+ * snd_compr_leave_draining_in_pause - Leave draining state when pause in draining
+ * @substream: compress substream to set
+ *
+ * In some platform, we need to leave draining state when we use pause in draining.
+ * Add API to allow leave draining state.
+ */
+static inline void snd_compr_leave_draining_in_pause(struct snd_compr_stream *substream)
+{
+	substream->device->leave_draining_in_pause = true;
+}
+
 /* dsp driver callback apis
  * For playback: driver should call snd_compress_fragment_elapsed() to let the
  * framework know that a fragment has been consumed from the ring buffer
diff --git a/sound/core/compress_offload.c b/sound/core/compress_offload.c
index 21ce4c056a92..c6e5c8f072d7 100644
--- a/sound/core/compress_offload.c
+++ b/sound/core/compress_offload.c
@@ -719,8 +719,14 @@ static int snd_compr_pause(struct snd_compr_stream *stream)
 		if (!stream->device->use_pause_in_draining)
 			return -EPERM;
 		retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
-		if (!retval)
+		if (!retval) {
+			if (stream->device->leave_draining_in_pause) {
+				stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
+				wake_up(&stream->runtime->sleep);
+				break;
+			}
 			stream->pause_in_draining = true;
+		}
 		break;
 	default:
 		return -EPERM;
-- 
2.32.0.93.g670b81a890-goog