ANDROID: ALSA: compress: add vendor hook to support pause in draining

Add a hook to query from vendor's compress driver if it is support pause
in draining and if the platform need to keep in draining state.

Bug: 184020292
Bug: 178992384

Change-Id: Id2e2ff72d7ee66fc633473ec109ed3d8a2baaeff
Signed-off-by: Robert Lee <lerobert@google.com>

drivers/android/vendor_hooks.c

@@ -71,6 +71,7 @@
 #include <trace/hooks/usb.h>
 #include <trace/hooks/ipv6.h>
 #include <trace/hooks/sound.h>
+#include <trace/hooks/snd_compr.h>
 
 /*
  * Export tracepoints that act as a bare tracehook (ie: have no trace event
@@ -360,3 +361,4 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_usb_dev_suspend);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_usb_dev_resume);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_ipv6_gen_linklocal_addr);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_sound_usb_support_cpu_suspend);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_snd_compr_use_pause_in_drain);

include/trace/hooks/snd_compr.h

@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM snd_compr
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH trace/hooks
+
+#if !defined(_TRACE_HOOK_SND_COMPR_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_HOOK_SND_COMPR_H
+
+#include <linux/tracepoint.h>
+#include <trace/hooks/vendor_hooks.h>
+/*
+ * Following tracepoints are not exported in tracefs and provide a
+ * mechanism for vendor modules to hook and extend functionality
+ */
+
+DECLARE_HOOK(android_vh_snd_compr_use_pause_in_drain,
+	TP_PROTO(bool *use_pause_in_drain, bool *leave_draining),
+	TP_ARGS(use_pause_in_drain, leave_draining));
+
+#endif /* _TRACE_HOOK_SND_COMPR_H */
+/* This part must be outside protection */
+#include <trace/define_trace.h>
+

sound/core/compress_offload.c

@@ -33,6 +33,10 @@
 #include <sound/compress_offload.h>
 #include <sound/compress_driver.h>
 
+#ifndef __GENKSYMS__
+#include <trace/hooks/snd_compr.h>
+#endif
+
 /* struct snd_compr_codec_caps overflows the ioctl bit size for some
  * architectures, so we need to disable the relevant ioctls.
  */
@@ -708,6 +712,20 @@ snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
 static int snd_compr_pause(struct snd_compr_stream *stream)
 {
 	int retval;
+	bool use_pause_in_drain = false;
+	bool leave_draining_state = false;
+
+	trace_android_vh_snd_compr_use_pause_in_drain(&use_pause_in_drain,
+				&leave_draining_state);
+
+	if (use_pause_in_drain && stream->runtime->state == SNDRV_PCM_STATE_DRAINING) {
+		retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
+		if (!retval && leave_draining_state) {
+			stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
+			wake_up(&stream->runtime->sleep);
+		}
+		return retval;
+	}
 
 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 		return -EPERM;
@@ -720,6 +738,14 @@ static int snd_compr_pause(struct snd_compr_stream *stream)
 static int snd_compr_resume(struct snd_compr_stream *stream)
 {
 	int retval;
+	bool use_pause_in_drain = false;
+	bool leave_draining_state = false;
+
+	trace_android_vh_snd_compr_use_pause_in_drain(&use_pause_in_drain,
+				&leave_draining_state);
+
+	if (use_pause_in_drain && stream->runtime->state == SNDRV_PCM_STATE_DRAINING)
+		return stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
 
 	if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
 		return -EPERM;