950-0398-staging-bcm2835-audio-Drop-useless-running-flag-and-.patch

From e8a202b4d06a07ba42b91a1dd3c2d9e9cedff32d Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Tue, 4 Sep 2018 17:58:37 +0200
Subject: [PATCH] staging: bcm2835-audio: Drop useless running flag and
 check

commit 02f2376321d75e78117f39ff81f215254ee6b4ef upstream.

The running flag of alsa_stream is basically useless.  The running
state is strictly controlled in ALSA PCM core side, hence the check in
PCM trigger and close callbacks are superfluous.

Also, the prefill ack at trigger start became superfluous nowadays
with the ALSA PCM core update.

Let's rip them off.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 .../vc04_services/bcm2835-audio/bcm2835-pcm.c | 46 ++++---------------
 .../vc04_services/bcm2835-audio/bcm2835.h     |  1 -
 2 files changed, 8 insertions(+), 39 deletions(-)

--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
@@ -187,19 +187,6 @@ static int snd_bcm2835_playback_close(st
 
 	audio_info("Alsa close\n");
 
-	/*
-	 * Call stop if it's still running. This happens when app
-	 * is force killed and we don't get a stop trigger.
-	 */
-	if (alsa_stream->running) {
-		int err;
-
-		err = bcm2835_audio_stop(alsa_stream);
-		alsa_stream->running = 0;
-		if (err)
-			audio_error(" Failed to STOP alsa device\n");
-	}
-
 	alsa_stream->period_size = 0;
 	alsa_stream->buffer_size = 0;
 
@@ -324,27 +311,13 @@ static int snd_bcm2835_pcm_trigger(struc
 
 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_START:
-		audio_debug("bcm2835_AUDIO_TRIGGER_START running=%d\n",
-			alsa_stream->running);
-		if (!alsa_stream->running) {
-			err = bcm2835_audio_start(alsa_stream);
-			if (!err) {
-				alsa_stream->pcm_indirect.hw_io =
-					alsa_stream->pcm_indirect.hw_data =
-					bytes_to_frames(runtime,
-					alsa_stream->pos);
-				substream->ops->ack(substream);
-				alsa_stream->running = 1;
-				alsa_stream->draining = 1;
-			} else {
-				audio_error(" Failed to START alsa device (%d)\n", err);
-			}
-		}
+		err = bcm2835_audio_start(alsa_stream);
+		if (!err)
+			alsa_stream->draining = 1;
+		else
+			audio_error(" Failed to START alsa device (%d)\n", err);
 		break;
 	case SNDRV_PCM_TRIGGER_STOP:
-		audio_debug
-			("bcm2835_AUDIO_TRIGGER_STOP running=%d draining=%d\n",
-			alsa_stream->running, runtime->status->state == SNDRV_PCM_STATE_DRAINING);
 		if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
 			audio_info("DRAINING\n");
 			alsa_stream->draining = 1;
@@ -352,12 +325,9 @@ static int snd_bcm2835_pcm_trigger(struc
 			audio_info("DROPPING\n");
 			alsa_stream->draining = 0;
 		}
-		if (alsa_stream->running) {
-			err = bcm2835_audio_stop(alsa_stream);
-			if (err != 0)
-				audio_error(" Failed to STOP alsa device (%d)\n", err);
-			alsa_stream->running = 0;
-		}
+		err = bcm2835_audio_stop(alsa_stream);
+		if (err != 0)
+			audio_error(" Failed to STOP alsa device (%d)\n", err);
 		break;
 	default:
 		err = -EINVAL;
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835.h
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835.h
@@ -121,7 +121,6 @@ struct bcm2835_alsa_stream {
 
 	spinlock_t lock;
 
-	int running;
 	int draining;
 
 	int channels;