ALSA: pcm: Improved XRUN handling for indirect PCM helpers

As PCM ack callback may handle the XRUN situation gracefully now,
change the indirect PCM helpers to give a proper error (-EPIPE).
Also, change the pointer callback helpers to deal with the XRUN error
properly, too.

This requires the PCM core change by the commit 8c721c53dda5
("ALSA: usb-audio: Fix recursive locking at XRUN during syncing").

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Takashi Iwai <[e-mail]>

include/sound/pcm-indirect.h

···
 		if (diff < -(snd_pcm_sframes_t) (runtime->boundary / 2))
 			diff += runtime->boundary;
 		if (diff < 0)
-			return -EINVAL;
+			return -EPIPE;
 		rec->sw_ready += (int)frames_to_bytes(runtime, diff);
 		rec->appl_ptr = appl_ptr;
 	}
···
 				  struct snd_pcm_indirect *rec, unsigned int ptr)
 {
 	int bytes = ptr - rec->hw_io;
+	int err;
+
 	if (bytes < 0)
 		bytes += rec->hw_buffer_size;
 	rec->hw_io = ptr;
···
 	rec->sw_io += bytes;
 	if (rec->sw_io >= rec->sw_buffer_size)
 		rec->sw_io -= rec->sw_buffer_size;
-	if (substream->ops->ack)
-		substream->ops->ack(substream);
+	if (substream->ops->ack) {
+		err = substream->ops->ack(substream);
+		if (err == -EPIPE)
+			return SNDRV_PCM_POS_XRUN;
+	}
 	return bytes_to_frames(substream->runtime, rec->sw_io);
 }
 
···
 		if (diff < -(snd_pcm_sframes_t) (runtime->boundary / 2))
 			diff += runtime->boundary;
 		if (diff < 0)
-			return -EINVAL;
+			return -EPIPE;
 		rec->sw_ready -= frames_to_bytes(runtime, diff);
 		rec->appl_ptr = appl_ptr;
 	}
···
 {
 	int qsize;
 	int bytes = ptr - rec->hw_io;
+	int err;
+
 	if (bytes < 0)
 		bytes += rec->hw_buffer_size;
 	rec->hw_io = ptr;
···
 	rec->sw_io += bytes;
 	if (rec->sw_io >= rec->sw_buffer_size)
 		rec->sw_io -= rec->sw_buffer_size;
-	if (substream->ops->ack)
-		substream->ops->ack(substream);
+	if (substream->ops->ack) {
+		err = substream->ops->ack(substream);
+		if (err == -EPIPE)
+			return SNDRV_PCM_POS_XRUN;
+	}
 	return bytes_to_frames(substream->runtime, rec->sw_io);
 }