ALSA: firewire-lib: taskletize the snd_pcm_period_elapsed() call
The following patch might introduce this call chain:
PCM .pointer callback
+ fw_iso_context_flush_completions
+ packet callback
+ snd_pcm_period_elapsed
+ PCM .pointer callback
Recursive calls to the pointer callback are not possible due to the PCM
group locking, so avoid this by moving the period notification into
a separate tasklet.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/firewire/amdtp.h b/sound/firewire/amdtp.h
index 537a9cb..4987f82 100644
--- a/sound/firewire/amdtp.h
+++ b/sound/firewire/amdtp.h
@@ -1,6 +1,7 @@
#ifndef SOUND_FIREWIRE_AMDTP_H_INCLUDED
#define SOUND_FIREWIRE_AMDTP_H_INCLUDED
+#include <linux/interrupt.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include "packets-buffer.h"
@@ -55,6 +56,7 @@
struct iso_packets_buffer buffer;
struct snd_pcm_substream *pcm;
+ struct tasklet_struct period_tasklet;
int packet_index;
unsigned int data_block_counter;
@@ -81,6 +83,7 @@
void amdtp_out_stream_set_pcm_format(struct amdtp_out_stream *s,
snd_pcm_format_t format);
+void amdtp_out_stream_pcm_prepare(struct amdtp_out_stream *s);
void amdtp_out_stream_pcm_abort(struct amdtp_out_stream *s);
/**
@@ -123,18 +126,6 @@
}
/**
- * amdtp_out_stream_pcm_prepare - prepare PCM device for running
- * @s: the AMDTP output stream
- *
- * This function should be called from the PCM device's .prepare callback.
- */
-static inline void amdtp_out_stream_pcm_prepare(struct amdtp_out_stream *s)
-{
- s->pcm_buffer_pointer = 0;
- s->pcm_period_pointer = 0;
-}
-
-/**
* amdtp_out_stream_pcm_trigger - start/stop playback from a PCM device
* @s: the AMDTP output stream
* @pcm: the PCM device to be started, or %NULL to stop the current device