linux-stable/sound/firewire/amdtp.h
Clemens Ladisch 92b862c7d6 ALSA: firewire-lib: optimize packet flushing
Trying to flush completed packets is pointless when the pointer
callback was called from the packet completion callback; avoid it.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2012-05-14 10:43:43 +02:00

150 lines
4.2 KiB
C

#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"
/**
* enum cip_out_flags - describes details of the streaming protocol
* @CIP_NONBLOCKING: In non-blocking mode, each packet contains
* sample_rate/8000 samples, with rounding up or down to adjust
* for clock skew and left-over fractional samples. This should
* be used if supported by the device.
*/
enum cip_out_flags {
CIP_NONBLOCKING = 0,
};
/**
* enum cip_sfc - a stream's sample rate
*/
enum cip_sfc {
CIP_SFC_32000 = 0,
CIP_SFC_44100 = 1,
CIP_SFC_48000 = 2,
CIP_SFC_88200 = 3,
CIP_SFC_96000 = 4,
CIP_SFC_176400 = 5,
CIP_SFC_192000 = 6,
};
#define AMDTP_OUT_PCM_FORMAT_BITS (SNDRV_PCM_FMTBIT_S16 | \
SNDRV_PCM_FMTBIT_S32)
struct fw_unit;
struct fw_iso_context;
struct snd_pcm_substream;
struct amdtp_out_stream {
struct fw_unit *unit;
enum cip_out_flags flags;
struct fw_iso_context *context;
struct mutex mutex;
enum cip_sfc sfc;
unsigned int data_block_quadlets;
unsigned int pcm_channels;
unsigned int midi_ports;
void (*transfer_samples)(struct amdtp_out_stream *s,
struct snd_pcm_substream *pcm,
__be32 *buffer, unsigned int frames);
unsigned int syt_interval;
unsigned int source_node_id_field;
struct iso_packets_buffer buffer;
struct snd_pcm_substream *pcm;
struct tasklet_struct period_tasklet;
int packet_index;
unsigned int data_block_counter;
unsigned int data_block_state;
unsigned int last_syt_offset;
unsigned int syt_offset_state;
unsigned int pcm_buffer_pointer;
unsigned int pcm_period_pointer;
bool pointer_flush;
};
int amdtp_out_stream_init(struct amdtp_out_stream *s, struct fw_unit *unit,
enum cip_out_flags flags);
void amdtp_out_stream_destroy(struct amdtp_out_stream *s);
void amdtp_out_stream_set_rate(struct amdtp_out_stream *s, unsigned int rate);
unsigned int amdtp_out_stream_get_max_payload(struct amdtp_out_stream *s);
int amdtp_out_stream_start(struct amdtp_out_stream *s, int channel, int speed);
void amdtp_out_stream_update(struct amdtp_out_stream *s);
void amdtp_out_stream_stop(struct amdtp_out_stream *s);
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);
unsigned long amdtp_out_stream_pcm_pointer(struct amdtp_out_stream *s);
void amdtp_out_stream_pcm_abort(struct amdtp_out_stream *s);
/**
* amdtp_out_stream_set_pcm - configure format of PCM samples
* @s: the AMDTP output stream to be configured
* @pcm_channels: the number of PCM samples in each data block, to be encoded
* as AM824 multi-bit linear audio
*
* This function must not be called while the stream is running.
*/
static inline void amdtp_out_stream_set_pcm(struct amdtp_out_stream *s,
unsigned int pcm_channels)
{
s->pcm_channels = pcm_channels;
}
/**
* amdtp_out_stream_set_midi - configure format of MIDI data
* @s: the AMDTP output stream to be configured
* @midi_ports: the number of MIDI ports (i.e., MPX-MIDI Data Channels)
*
* This function must not be called while the stream is running.
*/
static inline void amdtp_out_stream_set_midi(struct amdtp_out_stream *s,
unsigned int midi_ports)
{
s->midi_ports = midi_ports;
}
/**
* amdtp_out_streaming_error - check for streaming error
* @s: the AMDTP output stream
*
* If this function returns true, the stream's packet queue has stopped due to
* an asynchronous error.
*/
static inline bool amdtp_out_streaming_error(struct amdtp_out_stream *s)
{
return s->packet_index < 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
*
* Call this function on a running isochronous stream to enable the actual
* transmission of PCM data. This function should be called from the PCM
* device's .trigger callback.
*/
static inline void amdtp_out_stream_pcm_trigger(struct amdtp_out_stream *s,
struct snd_pcm_substream *pcm)
{
ACCESS_ONCE(s->pcm) = pcm;
}
static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
{
return sfc & 1;
}
#endif