ALSA: firewire: introduce amdtp_out_stream_running()

Introduce the helper function amdtp_out_stream_running().  This makes
many checks in amdtp.c clearer and frees the device drivers from having
to track this with a separate variable.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

sound/firewire/amdtp.c

@@ -59,7 +59,7 @@ EXPORT_SYMBOL(amdtp_out_stream_init);
  */
 void amdtp_out_stream_destroy(struct amdtp_out_stream *s)
 {
-	WARN_ON(!IS_ERR(s->context));
+	WARN_ON(amdtp_out_stream_running(s));
 	mutex_destroy(&s->mutex);
 	fw_unit_put(s->unit);
 }
@@ -89,7 +89,7 @@ void amdtp_out_stream_set_rate(struct amdtp_out_stream *s, unsigned int rate)
 	};
 	unsigned int sfc;
 
-	if (WARN_ON(!IS_ERR(s->context)))
+	if (WARN_ON(amdtp_out_stream_running(s)))
 		return;
 
 	for (sfc = 0; sfc < ARRAY_SIZE(rate_info); ++sfc)
@@ -145,7 +145,7 @@ static void amdtp_write_s32(struct amdtp_out_stream *s,
 void amdtp_out_stream_set_pcm_format(struct amdtp_out_stream *s,
 				     snd_pcm_format_t format)
 {
-	if (WARN_ON(!IS_ERR(s->context)))
+	if (WARN_ON(amdtp_out_stream_running(s)))
 		return;
 
 	switch (format) {
@@ -481,7 +481,7 @@ int amdtp_out_stream_start(struct amdtp_out_stream *s, int channel, int speed)
 
 	mutex_lock(&s->mutex);
 
-	if (WARN_ON(!IS_ERR(s->context) ||
+	if (WARN_ON(amdtp_out_stream_running(s) ||
 		    (!s->pcm_channels && !s->midi_ports))) {
 		err = -EBADFD;
 		goto err_unlock;
@@ -577,7 +577,7 @@ void amdtp_out_stream_stop(struct amdtp_out_stream *s)
 {
 	mutex_lock(&s->mutex);
 
-	if (IS_ERR(s->context)) {
+	if (!amdtp_out_stream_running(s)) {
 		mutex_unlock(&s->mutex);
 		return;
 	}

sound/firewire/amdtp.h

@@ -1,6 +1,7 @@
 #ifndef SOUND_FIREWIRE_AMDTP_H_INCLUDED
 #define SOUND_FIREWIRE_AMDTP_H_INCLUDED
 
+#include <linux/err.h>
 #include <linux/interrupt.h>
 #include <linux/mutex.h>
 #include "packets-buffer.h"
@@ -92,6 +93,11 @@ void amdtp_out_stream_pcm_prepare(struct amdtp_out_stream *s);
 unsigned long amdtp_out_stream_pcm_pointer(struct amdtp_out_stream *s);
 void amdtp_out_stream_pcm_abort(struct amdtp_out_stream *s);
 
+static inline bool amdtp_out_stream_running(struct amdtp_out_stream *s)
+{
+	return !IS_ERR(s->context);
+}
+
 /**
  * amdtp_out_stream_set_pcm - configure format of PCM samples
  * @s: the AMDTP output stream to be configured

sound/firewire/dice.c

@@ -246,7 +246,6 @@ struct dice {
 	int dev_lock_count; /* > 0 driver, < 0 userspace */
 	bool dev_lock_changed;
 	bool global_enabled;
-	bool stream_running;
 	wait_queue_head_t hwdep_wait;
 	u32 notification_bits;
 	struct snd_pcm_substream *pcm;
@@ -654,7 +653,7 @@ static int dice_stream_start_packets(struct dice *dice)
 {
 	int err;
 
-	if (dice->stream_running)
+	if (amdtp_out_stream_running(&dice->stream))
 		return 0;
 
 	err = amdtp_out_stream_start(&dice->stream, dice->resources.channel,
@@ -668,8 +667,6 @@ static int dice_stream_start_packets(struct dice *dice)
 		return err;
 	}
 
-	dice->stream_running = true;
-
 	return 0;
 }
 
@@ -712,14 +709,10 @@ static int dice_stream_start(struct dice *dice)
 
 static void dice_stream_stop_packets(struct dice *dice)
 {
-	if (!dice->stream_running)
-		return;
-
-	dice_enable_clear(dice);
-
-	amdtp_out_stream_stop(&dice->stream);
-
-	dice->stream_running = false;
+	if (amdtp_out_stream_running(&dice->stream)) {
+		dice_enable_clear(dice);
+		amdtp_out_stream_stop(&dice->stream);
+	}
 }
 
 static void dice_stream_stop(struct dice *dice)

sound/firewire/speakers.c

@@ -53,7 +53,6 @@ struct fwspk {
 	struct mutex mutex;
 	struct cmp_connection connection;
 	struct amdtp_out_stream stream;
-	bool stream_running;
 	bool mute;
 	s16 volume[6];
 	s16 volume_min;
@@ -189,10 +188,9 @@ static int fwspk_close(struct snd_pcm_substream *substream)
 
 static void fwspk_stop_stream(struct fwspk *fwspk)
 {
-	if (fwspk->stream_running) {
+	if (amdtp_out_stream_running(&fwspk->stream)) {
 		amdtp_out_stream_stop(&fwspk->stream);
 		cmp_connection_break(&fwspk->connection);
-		fwspk->stream_running = false;
 	}
 }
 
@@ -286,7 +284,7 @@ static int fwspk_prepare(struct snd_pcm_substream *substream)
 	if (amdtp_out_streaming_error(&fwspk->stream))
 		fwspk_stop_stream(fwspk);
 
-	if (!fwspk->stream_running) {
+	if (!amdtp_out_stream_running(&fwspk->stream)) {
 		err = cmp_connection_establish(&fwspk->connection,
 			amdtp_out_stream_get_max_payload(&fwspk->stream));
 		if (err < 0)
@@ -297,8 +295,6 @@ static int fwspk_prepare(struct snd_pcm_substream *substream)
 					fwspk->connection.speed);
 		if (err < 0)
 			goto err_connection;
-
-		fwspk->stream_running = true;
 	}
 
 	mutex_unlock(&fwspk->mutex);