LXR linux/sound/firewire/amdtp-stream.h

   1#ifndef SOUND_FIREWIRE_AMDTP_H_INCLUDED
   2#define SOUND_FIREWIRE_AMDTP_H_INCLUDED
   3
   4#include <linux/err.h>
   5#include <linux/interrupt.h>
   6#include <linux/mutex.h>
   7#include <linux/sched.h>
   8#include <sound/asound.h>
   9#include "packets-buffer.h"
  10
  11/**
  12 * enum cip_flags - describes details of the streaming protocol
  13 * @CIP_NONBLOCKING: In non-blocking mode, each packet contains
  14 *      sample_rate/8000 samples, with rounding up or down to adjust
  15 *      for clock skew and left-over fractional samples.  This should
  16 *      be used if supported by the device.
  17 * @CIP_BLOCKING: In blocking mode, each packet contains either zero or
  18 *      SYT_INTERVAL samples, with these two types alternating so that
  19 *      the overall sample rate comes out right.
  20 * @CIP_EMPTY_WITH_TAG0: Only for in-stream. Empty in-packets have TAG0.
  21 * @CIP_DBC_IS_END_EVENT: Only for in-stream. The value of dbc in an in-packet
  22 *      corresponds to the end of event in the packet. Out of IEC 61883.
  23 * @CIP_WRONG_DBS: Only for in-stream. The value of dbs is wrong in in-packets.
  24 *      The value of data_block_quadlets is used instead of reported value.
  25 * @CIP_SKIP_DBC_ZERO_CHECK: Only for in-stream.  Packets with zero in dbc is
  26 *      skipped for detecting discontinuity.
  27 * @CIP_EMPTY_HAS_WRONG_DBC: Only for in-stream. The value of dbc in empty
  28 *      packet is wrong but the others are correct.
  29 * @CIP_JUMBO_PAYLOAD: Only for in-stream. The number of data blocks in an
  30 *      packet is larger than IEC 61883-6 defines. Current implementation
  31 *      allows 5 times as large as IEC 61883-6 defines.
  32 */
  33enum cip_flags {
  34        CIP_NONBLOCKING         = 0x00,
  35        CIP_BLOCKING            = 0x01,
  36        CIP_EMPTY_WITH_TAG0     = 0x02,
  37        CIP_DBC_IS_END_EVENT    = 0x04,
  38        CIP_WRONG_DBS           = 0x08,
  39        CIP_SKIP_DBC_ZERO_CHECK = 0x10,
  40        CIP_EMPTY_HAS_WRONG_DBC = 0x20,
  41        CIP_JUMBO_PAYLOAD       = 0x40,
  42};
  43
  44/**
  45 * enum cip_sfc - supported Sampling Frequency Codes (SFCs)
  46 * @CIP_SFC_32000:   32,000 data blocks
  47 * @CIP_SFC_44100:   44,100 data blocks
  48 * @CIP_SFC_48000:   48,000 data blocks
  49 * @CIP_SFC_88200:   88,200 data blocks
  50 * @CIP_SFC_96000:   96,000 data blocks
  51 * @CIP_SFC_176400: 176,400 data blocks
  52 * @CIP_SFC_192000: 192,000 data blocks
  53 * @CIP_SFC_COUNT: the number of supported SFCs
  54 *
  55 * These values are used to show nominal Sampling Frequency Code in
  56 * Format Dependent Field (FDF) of AMDTP packet header. In IEC 61883-6:2002,
  57 * this code means the number of events per second. Actually the code
  58 * represents the number of data blocks transferred per second in an AMDTP
  59 * stream.
  60 *
  61 * In IEC 61883-6:2005, some extensions were added to support more types of
  62 * data such as 'One Bit LInear Audio', therefore the meaning of SFC became
  63 * different depending on the types.
  64 *
  65 * Currently our implementation is compatible with IEC 61883-6:2002.
  66 */
  67enum cip_sfc {
  68        CIP_SFC_32000  = 0,
  69        CIP_SFC_44100  = 1,
  70        CIP_SFC_48000  = 2,
  71        CIP_SFC_88200  = 3,
  72        CIP_SFC_96000  = 4,
  73        CIP_SFC_176400 = 5,
  74        CIP_SFC_192000 = 6,
  75        CIP_SFC_COUNT
  76};
  77
  78struct fw_unit;
  79struct fw_iso_context;
  80struct snd_pcm_substream;
  81struct snd_pcm_runtime;
  82
  83enum amdtp_stream_direction {
  84        AMDTP_OUT_STREAM = 0,
  85        AMDTP_IN_STREAM
  86};
  87
  88struct amdtp_stream;
  89typedef unsigned int (*amdtp_stream_process_data_blocks_t)(
  90                                                struct amdtp_stream *s,
  91                                                __be32 *buffer,
  92                                                unsigned int data_blocks,
  93                                                unsigned int *syt);
  94struct amdtp_stream {
  95        struct fw_unit *unit;
  96        enum cip_flags flags;
  97        enum amdtp_stream_direction direction;
  98        struct mutex mutex;
  99
 100        /* For packet processing. */
 101        struct fw_iso_context *context;
 102        struct iso_packets_buffer buffer;
 103        int packet_index;
 104
 105        /* For CIP headers. */
 106        unsigned int source_node_id_field;
 107        unsigned int data_block_quadlets;
 108        unsigned int data_block_counter;
 109        unsigned int fmt;
 110        unsigned int fdf;
 111        /* quirk: fixed interval of dbc between previos/current packets. */
 112        unsigned int tx_dbc_interval;
 113        /* quirk: indicate the value of dbc field in a first packet. */
 114        unsigned int tx_first_dbc;
 115
 116        /* Internal flags. */
 117        enum cip_sfc sfc;
 118        unsigned int syt_interval;
 119        unsigned int transfer_delay;
 120        unsigned int data_block_state;
 121        unsigned int last_syt_offset;
 122        unsigned int syt_offset_state;
 123
 124        /* For a PCM substream processing. */
 125        struct snd_pcm_substream *pcm;
 126        struct tasklet_struct period_tasklet;
 127        unsigned int pcm_buffer_pointer;
 128        unsigned int pcm_period_pointer;
 129
 130        /* To wait for first packet. */
 131        bool callbacked;
 132        wait_queue_head_t callback_wait;
 133
 134        /* For backends to process data blocks. */
 135        void *protocol;
 136        amdtp_stream_process_data_blocks_t process_data_blocks;
 137};
 138
 139int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
 140                      enum amdtp_stream_direction dir, enum cip_flags flags,
 141                      unsigned int fmt,
 142                      amdtp_stream_process_data_blocks_t process_data_blocks,
 143                      unsigned int protocol_size);
 144void amdtp_stream_destroy(struct amdtp_stream *s);
 145
 146int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
 147                                unsigned int data_block_quadlets);
 148unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
 149
 150int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
 151void amdtp_stream_update(struct amdtp_stream *s);
 152void amdtp_stream_stop(struct amdtp_stream *s);
 153
 154int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
 155                                        struct snd_pcm_runtime *runtime);
 156
 157void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
 158unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
 159void amdtp_stream_pcm_abort(struct amdtp_stream *s);
 160
 161extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
 162extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
 163
 164/**
 165 * amdtp_stream_running - check stream is running or not
 166 * @s: the AMDTP stream
 167 *
 168 * If this function returns true, the stream is running.
 169 */
 170static inline bool amdtp_stream_running(struct amdtp_stream *s)
 171{
 172        return !IS_ERR(s->context);
 173}
 174
 175/**
 176 * amdtp_streaming_error - check for streaming error
 177 * @s: the AMDTP stream
 178 *
 179 * If this function returns true, the stream's packet queue has stopped due to
 180 * an asynchronous error.
 181 */
 182static inline bool amdtp_streaming_error(struct amdtp_stream *s)
 183{
 184        return s->packet_index < 0;
 185}
 186
 187/**
 188 * amdtp_stream_pcm_running - check PCM substream is running or not
 189 * @s: the AMDTP stream
 190 *
 191 * If this function returns true, PCM substream in the AMDTP stream is running.
 192 */
 193static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
 194{
 195        return !!s->pcm;
 196}
 197
 198/**
 199 * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
 200 * @s: the AMDTP stream
 201 * @pcm: the PCM device to be started, or %NULL to stop the current device
 202 *
 203 * Call this function on a running isochronous stream to enable the actual
 204 * transmission of PCM data.  This function should be called from the PCM
 205 * device's .trigger callback.
 206 */
 207static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
 208                                            struct snd_pcm_substream *pcm)
 209{
 210        ACCESS_ONCE(s->pcm) = pcm;
 211}
 212
 213static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
 214{
 215        return sfc & 1;
 216}
 217
 218/**
 219 * amdtp_stream_wait_callback - sleep till callbacked or timeout
 220 * @s: the AMDTP stream
 221 * @timeout: msec till timeout
 222 *
 223 * If this function return false, the AMDTP stream should be stopped.
 224 */
 225static inline bool amdtp_stream_wait_callback(struct amdtp_stream *s,
 226                                              unsigned int timeout)
 227{
 228        return wait_event_timeout(s->callback_wait,
 229                                  s->callbacked == true,
 230                                  msecs_to_jiffies(timeout)) > 0;
 231}
 232
 233#endif
 234