linux/sound/firewire/amdtp.h
Clemens Ladisch ec00f5e444 ALSA: firewire-lib, firewire-speakers: handle packet queueing errors
Add an AMDTP stream error state that occurs when we fail to queue
another packet.  In this case, the stream is stopped, and the error can
be reported when the application tries to restart the PCM stream.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-03-15 08:42:30 +01:00

170 lines
4.6 KiB
C

#ifndef SOUND_FIREWIRE_AMDTP_H_INCLUDED
#define SOUND_FIREWIRE_AMDTP_H_INCLUDED
#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;
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;
};
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_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_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
*
* 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;
}
/**
* amdtp_out_stream_pcm_pointer - get the PCM buffer position
* @s: the AMDTP output stream that transports the PCM data
*
* Returns the current buffer position, in frames.
*/
static inline unsigned long
amdtp_out_stream_pcm_pointer(struct amdtp_out_stream *s)
{
return ACCESS_ONCE(s->pcm_buffer_pointer);
}
static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
{
return sfc & 1;
}
#endif