ALSA: bcm2835: don't use magic numbers on audio start/stop workqueue

The bcm2835 driver uses a workqueue to defer PCM playback start
and stop. Commands are passed to the function as magic numbers
so is more readable to use macro constants.

Also, while being there change the generic name "x" to "cmd"
for the var used to pass the start/stop commands.

Signed-off-by: Javier Martinez Canillas <[email protected]>

sound/arm/bcm2835-vchiq.c

@@ -38,6 +38,9 @@
 
 /* ---- Private Constants and Types ------------------------------------------ */
 
+#define BCM2835_AUDIO_STOP           0
+#define BCM2835_AUDIO_START          1
+
 /* Logging macros (for remapping to other logging mechanisms, i.e., printf) */
 #ifdef AUDIO_DEBUG_ENABLE
 	#define LOG_ERR( fmt, arg... )   pr_err( "%s:%d " fmt, __func__, __LINE__, ##arg)
@@ -75,23 +78,23 @@ static int bcm2835_audio_start_worker(bcm2835_alsa_stream_t * alsa_stream);
 typedef struct {
 	struct work_struct my_work;
 	bcm2835_alsa_stream_t *alsa_stream;
-	int x;
+	int cmd;
 } my_work_t;
 
 static void my_wq_function(struct work_struct *work)
 {
 	my_work_t *w = (my_work_t *) work;
 	int ret = -9;
-	LOG_DBG(" .. IN %p:%d\n", w->alsa_stream, w->x);
-	switch (w->x) {
-	case 1:
+	LOG_DBG(" .. IN %p:%d\n", w->alsa_stream, w->cmd);
+	switch (w->cmd) {
+	case BCM2835_AUDIO_START:
 		ret = bcm2835_audio_start_worker(w->alsa_stream);
 		break;
-	case 2:
+	case BCM2835_AUDIO_STOP:
 		ret = bcm2835_audio_stop_worker(w->alsa_stream);
 		break;
 	default:
-		LOG_ERR(" Unexpected work: %p:%d\n", w->alsa_stream, w->x);
+		LOG_ERR(" Unexpected work: %p:%d\n", w->alsa_stream, w->cmd);
 		break;
 	}
 	kfree((void *)work);
@@ -108,7 +111,7 @@ int bcm2835_audio_start(bcm2835_alsa_stream_t * alsa_stream)
 		if (work) {
 			INIT_WORK((struct work_struct *)work, my_wq_function);
 			work->alsa_stream = alsa_stream;
-			work->x = 1;
+			work->cmd = BCM2835_AUDIO_START;
 			if (queue_work
 			    (alsa_stream->my_wq, (struct work_struct *)work))
 				ret = 0;
@@ -129,7 +132,7 @@ int bcm2835_audio_stop(bcm2835_alsa_stream_t * alsa_stream)
 		if (work) {
 			INIT_WORK((struct work_struct *)work, my_wq_function);
 			work->alsa_stream = alsa_stream;
-			work->x = 2;
+			work->cmd = BCM2835_AUDIO_STOP;
 			if (queue_work
 			    (alsa_stream->my_wq, (struct work_struct *)work))
 				ret = 0;