Merge branch 'topic/pcm-jiffies-check' into for-linus

* topic/pcm-jiffies-check:
  ALSA: pcm - A helper function to compose PCM stream name for debug prints
  ALSA: pcm - Fix update of runtime->hw_ptr_interrupt
  ALSA: pcm - Fix a typo in hw_ptr update check
  ALSA: PCM midlevel: lower jiffies check margin using runtime->delay value
  ALSA: PCM midlevel: Do not update hw_ptr_jiffies when hw_ptr is not changed
  ALSA: PCM midlevel: introduce mask for xrun_debug() macro
  ALSA: PCM midlevel: improve fifo_size handling

include/sound/asound.h

@@ -255,6 +255,7 @@ typedef int __bitwise snd_pcm_subformat_t;
 #define SNDRV_PCM_INFO_HALF_DUPLEX	0x00100000	/* only half duplex */
 #define SNDRV_PCM_INFO_JOINT_DUPLEX	0x00200000	/* playback and capture stream are somewhat correlated */
 #define SNDRV_PCM_INFO_SYNC_START	0x00400000	/* pcm support some kind of sync go */
+#define SNDRV_PCM_INFO_FIFO_IN_FRAMES	0x80000000	/* internal kernel flag - FIFO size is in frames */
 
 typedef int __bitwise snd_pcm_state_t;
 #define	SNDRV_PCM_STATE_OPEN		((__force snd_pcm_state_t) 0) /* stream is open */

include/sound/pcm.h

@@ -98,6 +98,7 @@ struct snd_pcm_ops {
 #define SNDRV_PCM_IOCTL1_INFO		1
 #define SNDRV_PCM_IOCTL1_CHANNEL_INFO	2
 #define SNDRV_PCM_IOCTL1_GSTATE		3
+#define SNDRV_PCM_IOCTL1_FIFO_SIZE	4
 
 #define SNDRV_PCM_TRIGGER_STOP		0
 #define SNDRV_PCM_TRIGGER_START		1

sound/core/pcm_lib.c

@@ -127,24 +127,37 @@ void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_ufram
 }
 
 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
-#define xrun_debug(substream)	((substream)->pstr->xrun_debug)
+#define xrun_debug(substream, mask)	((substream)->pstr->xrun_debug & (mask))
 #else
-#define xrun_debug(substream)	0
+#define xrun_debug(substream, mask)	0
 #endif
 
-#define dump_stack_on_xrun(substream) do {	\
-		if (xrun_debug(substream) > 1)	\
-			dump_stack();		\
+#define dump_stack_on_xrun(substream) do {		\
+		if (xrun_debug(substream, 2))		\
+			dump_stack();			\
 	} while (0)
 
+static void pcm_debug_name(struct snd_pcm_substream *substream,
+			   char *name, size_t len)
+{
+	snprintf(name, len, "pcmC%dD%d%c:%d",
+		 substream->pcm->card->number,
+		 substream->pcm->device,
+		 substream->stream ? 'c' : 'p',
+		 substream->number);
+}
+
 static void xrun(struct snd_pcm_substream *substream)
 {
+	struct snd_pcm_runtime *runtime = substream->runtime;
+
+	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
+		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 	snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
-	if (xrun_debug(substream)) {
-		snd_printd(KERN_DEBUG "XRUN: pcmC%dD%d%c\n",
-			   substream->pcm->card->number,
-			   substream->pcm->device,
-			   substream->stream ? 'c' : 'p');
+	if (xrun_debug(substream, 1)) {
+		char name[16];
+		pcm_debug_name(substream, name, sizeof(name));
+		snd_printd(KERN_DEBUG "XRUN: %s\n", name);
 		dump_stack_on_xrun(substream);
 	}
 }
@@ -155,16 +168,16 @@ snd_pcm_update_hw_ptr_pos(struct snd_pcm_substream *substream,
 {
 	snd_pcm_uframes_t pos;
 
-	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
-		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 	pos = substream->ops->pointer(substream);
 	if (pos == SNDRV_PCM_POS_XRUN)
 		return pos; /* XRUN */
 	if (pos >= runtime->buffer_size) {
 		if (printk_ratelimit()) {
-			snd_printd(KERN_ERR  "BUG: stream = %i, pos = 0x%lx, "
+			char name[16];
+			pcm_debug_name(substream, name, sizeof(name));
+			snd_printd(KERN_ERR  "BUG: %s, pos = 0x%lx, "
 				   "buffer size = 0x%lx, period size = 0x%lx\n",
-				   substream->stream, pos, runtime->buffer_size,
+				   name, pos, runtime->buffer_size,
 				   runtime->period_size);
 		}
 		pos = 0;
@@ -198,7 +211,7 @@ static int snd_pcm_update_hw_ptr_post(struct snd_pcm_substream *substream,
 
 #define hw_ptr_error(substream, fmt, args...)				\
 	do {								\
-		if (xrun_debug(substream)) {				\
+		if (xrun_debug(substream, 1)) {				\
 			if (printk_ratelimit()) {			\
 				snd_printd("PCM: " fmt, ##args);	\
 			}						\
@@ -252,7 +265,7 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream)
 	}
 
 	/* Do jiffies check only in xrun_debug mode */
-	if (!xrun_debug(substream))
+	if (!xrun_debug(substream, 4))
 		goto no_jiffies_check;
 
 	/* Skip the jiffies check for hardwares with BATCH flag.
@@ -262,6 +275,9 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream)
 	if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
 		goto no_jiffies_check;
 	hdelta = new_hw_ptr - old_hw_ptr;
+	if (hdelta < runtime->delay)
+		goto no_jiffies_check;
+	hdelta -= runtime->delay;
 	jdelta = jiffies - runtime->hw_ptr_jiffies;
 	if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
 		delta = jdelta /
@@ -295,14 +311,20 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream)
 		hw_ptr_interrupt =
 			new_hw_ptr - new_hw_ptr % runtime->period_size;
 	}
+	runtime->hw_ptr_interrupt = hw_ptr_interrupt;
+
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 	    runtime->silence_size > 0)
 		snd_pcm_playback_silence(substream, new_hw_ptr);
 
+	if (runtime->status->hw_ptr == new_hw_ptr)
+		return 0;
+
 	runtime->hw_ptr_base = hw_base;
 	runtime->status->hw_ptr = new_hw_ptr;
 	runtime->hw_ptr_jiffies = jiffies;
-	runtime->hw_ptr_interrupt = hw_ptr_interrupt;
+	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
+		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 
 	return snd_pcm_update_hw_ptr_post(substream, runtime);
 }
@@ -343,8 +365,12 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 		new_hw_ptr = hw_base + pos;
 	}
 	/* Do jiffies check only in xrun_debug mode */
-	if (xrun_debug(substream) &&
-	    ((delta * HZ) / runtime->rate) > jdelta + HZ/100) {
+	if (!xrun_debug(substream, 4))
+		goto no_jiffies_check;
+	if (delta < runtime->delay)
+		goto no_jiffies_check;
+	delta -= runtime->delay;
+	if (((delta * HZ) / runtime->rate) > jdelta + HZ/100) {
 		hw_ptr_error(substream,
 			     "hw_ptr skipping! "
 			     "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu)\n",
@@ -353,13 +379,19 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 			     ((delta * HZ) / runtime->rate));
 		return 0;
 	}
+ no_jiffies_check:
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 	    runtime->silence_size > 0)
 		snd_pcm_playback_silence(substream, new_hw_ptr);
 
+	if (runtime->status->hw_ptr == new_hw_ptr)
+		return 0;
+
 	runtime->hw_ptr_base = hw_base;
 	runtime->status->hw_ptr = new_hw_ptr;
 	runtime->hw_ptr_jiffies = jiffies;
+	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
+		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 
 	return snd_pcm_update_hw_ptr_post(substream, runtime);
 }
@@ -1525,6 +1557,23 @@ static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
 	return 0;
 }
 
+static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
+				       void *arg)
+{
+	struct snd_pcm_hw_params *params = arg;
+	snd_pcm_format_t format;
+	int channels, width;
+
+	params->fifo_size = substream->runtime->hw.fifo_size;
+	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
+		format = params_format(params);
+		channels = params_channels(params);
+		width = snd_pcm_format_physical_width(format);
+		params->fifo_size /= width * channels;
+	}
+	return 0;
+}
+
 /**
  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
  * @substream: the pcm substream instance
@@ -1546,6 +1595,8 @@ int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
 		return snd_pcm_lib_ioctl_reset(substream, arg);
 	case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
 		return snd_pcm_lib_ioctl_channel_info(substream, arg);
+	case SNDRV_PCM_IOCTL1_FIFO_SIZE:
+		return snd_pcm_lib_ioctl_fifo_size(substream, arg);
 	}
 	return -ENXIO;
 }

sound/core/pcm_native.c

@@ -312,9 +312,18 @@ int snd_pcm_hw_refine(struct snd_pcm_substream *substream,
 
 	hw = &substream->runtime->hw;
 	if (!params->info)
-		params->info = hw->info;
-	if (!params->fifo_size)
-		params->fifo_size = hw->fifo_size;
+		params->info = hw->info & ~SNDRV_PCM_INFO_FIFO_IN_FRAMES;
+	if (!params->fifo_size) {
+		if (snd_mask_min(&params->masks[SNDRV_PCM_HW_PARAM_FORMAT]) ==
+		    snd_mask_max(&params->masks[SNDRV_PCM_HW_PARAM_FORMAT]) &&
+                    snd_mask_min(&params->masks[SNDRV_PCM_HW_PARAM_CHANNELS]) ==
+                    snd_mask_max(&params->masks[SNDRV_PCM_HW_PARAM_CHANNELS])) {
+			changed = substream->ops->ioctl(substream,
+					SNDRV_PCM_IOCTL1_FIFO_SIZE, params);
+			if (params < 0)
+				return changed;
+		}
+	}
 	params->rmask = 0;
 	return 0;
 }