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: The value of dbc in an packet corresponds to the end
  22 * 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 * @CIP_HEADER_WITHOUT_EOH: Only for in-stream. CIP Header doesn't include
  33 *      valid EOH.
  34 * @CIP_NO_HEADERS: a lack of headers in packets
  35 */
  36enum cip_flags {
  37        CIP_NONBLOCKING         = 0x00,
  38        CIP_BLOCKING            = 0x01,
  39        CIP_EMPTY_WITH_TAG0     = 0x02,
  40        CIP_DBC_IS_END_EVENT    = 0x04,
  41        CIP_WRONG_DBS           = 0x08,
  42        CIP_SKIP_DBC_ZERO_CHECK = 0x10,
  43        CIP_EMPTY_HAS_WRONG_DBC = 0x20,
  44        CIP_JUMBO_PAYLOAD       = 0x40,
  45        CIP_HEADER_WITHOUT_EOH  = 0x80,
  46        CIP_NO_HEADER           = 0x100,
  47};
  48
  49/**
  50 * enum cip_sfc - supported Sampling Frequency Codes (SFCs)
  51 * @CIP_SFC_32000:   32,000 data blocks
  52 * @CIP_SFC_44100:   44,100 data blocks
  53 * @CIP_SFC_48000:   48,000 data blocks
  54 * @CIP_SFC_88200:   88,200 data blocks
  55 * @CIP_SFC_96000:   96,000 data blocks
  56 * @CIP_SFC_176400: 176,400 data blocks
  57 * @CIP_SFC_192000: 192,000 data blocks
  58 * @CIP_SFC_COUNT: the number of supported SFCs
  59 *
  60 * These values are used to show nominal Sampling Frequency Code in
  61 * Format Dependent Field (FDF) of AMDTP packet header. In IEC 61883-6:2002,
  62 * this code means the number of events per second. Actually the code
  63 * represents the number of data blocks transferred per second in an AMDTP
  64 * stream.
  65 *
  66 * In IEC 61883-6:2005, some extensions were added to support more types of
  67 * data such as 'One Bit LInear Audio', therefore the meaning of SFC became
  68 * different depending on the types.
  69 *
  70 * Currently our implementation is compatible with IEC 61883-6:2002.
  71 */
  72enum cip_sfc {
  73        CIP_SFC_32000  = 0,
  74        CIP_SFC_44100  = 1,
  75        CIP_SFC_48000  = 2,
  76        CIP_SFC_88200  = 3,
  77        CIP_SFC_96000  = 4,
  78        CIP_SFC_176400 = 5,
  79        CIP_SFC_192000 = 6,
  80        CIP_SFC_COUNT
  81};
  82
  83struct fw_unit;
  84struct fw_iso_context;
  85struct snd_pcm_substream;
  86struct snd_pcm_runtime;
  87
  88enum amdtp_stream_direction {
  89        AMDTP_OUT_STREAM = 0,
  90        AMDTP_IN_STREAM
  91};
  92
  93struct amdtp_stream;
  94typedef unsigned int (*amdtp_stream_process_data_blocks_t)(
  95                                                struct amdtp_stream *s,
  96                                                __be32 *buffer,
  97                                                unsigned int data_blocks,
  98                                                unsigned int *syt);
  99struct amdtp_stream {
 100        struct fw_unit *unit;
 101        enum cip_flags flags;
 102        enum amdtp_stream_direction direction;
 103        struct mutex mutex;
 104
 105        /* For packet processing. */
 106        struct fw_iso_context *context;
 107        struct iso_packets_buffer buffer;
 108        int packet_index;
 109        int tag;
 110        int (*handle_packet)(struct amdtp_stream *s,
 111                        unsigned int payload_quadlets, unsigned int cycle,
 112                        unsigned int index);
 113        unsigned int max_payload_length;
 114
 115        /* For CIP headers. */
 116        unsigned int source_node_id_field;
 117        unsigned int data_block_quadlets;
 118        unsigned int data_block_counter;
 119        unsigned int sph;
 120        unsigned int fmt;
 121        unsigned int fdf;
 122        /* quirk: fixed interval of dbc between previos/current packets. */
 123        unsigned int tx_dbc_interval;
 124        /* quirk: indicate the value of dbc field in a first packet. */
 125        unsigned int tx_first_dbc;
 126
 127        /* Internal flags. */
 128        enum cip_sfc sfc;
 129        unsigned int syt_interval;
 130        unsigned int transfer_delay;
 131        unsigned int data_block_state;
 132        unsigned int last_syt_offset;
 133        unsigned int syt_offset_state;
 134
 135        /* For a PCM substream processing. */
 136        struct snd_pcm_substream *pcm;
 137        struct tasklet_struct period_tasklet;
 138        snd_pcm_uframes_t pcm_buffer_pointer;
 139        unsigned int pcm_period_pointer;
 140
 141        /* To wait for first packet. */
 142        bool callbacked;
 143        wait_queue_head_t callback_wait;
 144        u32 start_cycle;
 145
 146        /* For backends to process data blocks. */
 147        void *protocol;
 148        amdtp_stream_process_data_blocks_t process_data_blocks;
 149};
 150
 151int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
 152                      enum amdtp_stream_direction dir, enum cip_flags flags,
 153                      unsigned int fmt,
 154                      amdtp_stream_process_data_blocks_t process_data_blocks,
 155                      unsigned int protocol_size);
 156void amdtp_stream_destroy(struct amdtp_stream *s);
 157
 158int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
 159                                unsigned int data_block_quadlets);
 160unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
 161
 162int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
 163void amdtp_stream_update(struct amdtp_stream *s);
 164void amdtp_stream_stop(struct amdtp_stream *s);
 165
 166int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
 167                                        struct snd_pcm_runtime *runtime);
 168
 169void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
 170unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
 171int amdtp_stream_pcm_ack(struct amdtp_stream *s);
 172void amdtp_stream_pcm_abort(struct amdtp_stream *s);
 173
 174extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
 175extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
 176
 177/**
 178 * amdtp_stream_running - check stream is running or not
 179 * @s: the AMDTP stream
 180 *
 181 * If this function returns true, the stream is running.
 182 */
 183static inline bool amdtp_stream_running(struct amdtp_stream *s)
 184{
 185        return !IS_ERR(s->context);
 186}
 187
 188/**
 189 * amdtp_streaming_error - check for streaming error
 190 * @s: the AMDTP stream
 191 *
 192 * If this function returns true, the stream's packet queue has stopped due to
 193 * an asynchronous error.
 194 */
 195static inline bool amdtp_streaming_error(struct amdtp_stream *s)
 196{
 197        return s->packet_index < 0;
 198}
 199
 200/**
 201 * amdtp_stream_pcm_running - check PCM substream is running or not
 202 * @s: the AMDTP stream
 203 *
 204 * If this function returns true, PCM substream in the AMDTP stream is running.
 205 */
 206static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
 207{
 208        return !!s->pcm;
 209}
 210
 211/**
 212 * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
 213 * @s: the AMDTP stream
 214 * @pcm: the PCM device to be started, or %NULL to stop the current device
 215 *
 216 * Call this function on a running isochronous stream to enable the actual
 217 * transmission of PCM data.  This function should be called from the PCM
 218 * device's .trigger callback.
 219 */
 220static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
 221                                            struct snd_pcm_substream *pcm)
 222{
 223        ACCESS_ONCE(s->pcm) = pcm;
 224}
 225
 226static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
 227{
 228        return sfc & 1;
 229}
 230
 231/**
 232 * amdtp_stream_wait_callback - sleep till callbacked or timeout
 233 * @s: the AMDTP stream
 234 * @timeout: msec till timeout
 235 *
 236 * If this function return false, the AMDTP stream should be stopped.
 237 */
 238static inline bool amdtp_stream_wait_callback(struct amdtp_stream *s,
 239                                              unsigned int timeout)
 240{
 241        return wait_event_timeout(s->callback_wait,
 242                                  s->callbacked == true,
 243                                  msecs_to_jiffies(timeout)) > 0;
 244}
 245
 246#endif
 247