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_SYNC_TO_DEVICE: In sync to device mode, time stamp in out packets is
  21  *      generated by in packets. Defaultly this driver generates timestamp.
  22  * @CIP_EMPTY_WITH_TAG0: Only for in-stream. Empty in-packets have TAG0.
  23  * @CIP_DBC_IS_END_EVENT: Only for in-stream. The value of dbc in an in-packet
  24  *      corresponds to the end of event in the packet. Out of IEC 61883.
  25  * @CIP_WRONG_DBS: Only for in-stream. The value of dbs is wrong in in-packets.
  26  *      The value of data_block_quadlets is used instead of reported value.
  27  * @CIP_SKIP_DBC_ZERO_CHECK: Only for in-stream.  Packets with zero in dbc is
  28  *      skipped for detecting discontinuity.
  29  * @CIP_SKIP_INIT_DBC_CHECK: Only for in-stream. The value of dbc in first
  30  *      packet is not continuous from an initial value.
  31  * @CIP_EMPTY_HAS_WRONG_DBC: Only for in-stream. The value of dbc in empty
  32  *      packet is wrong but the others are correct.
  33  * @CIP_JUMBO_PAYLOAD: Only for in-stream. The number of data blocks in an
  34  *      packet is larger than IEC 61883-6 defines. Current implementation
  35  *      allows 5 times as large as IEC 61883-6 defines.
  36  */
  37 enum cip_flags {
  38         CIP_NONBLOCKING         = 0x00,
  39         CIP_BLOCKING            = 0x01,
  40         CIP_SYNC_TO_DEVICE      = 0x02,
  41         CIP_EMPTY_WITH_TAG0     = 0x04,
  42         CIP_DBC_IS_END_EVENT    = 0x08,
  43         CIP_WRONG_DBS           = 0x10,
  44         CIP_SKIP_DBC_ZERO_CHECK = 0x20,
  45         CIP_SKIP_INIT_DBC_CHECK = 0x40,
  46         CIP_EMPTY_HAS_WRONG_DBC = 0x80,
  47         CIP_JUMBO_PAYLOAD       = 0x100,
  48 };
  49
  50 /**
  51  * enum cip_sfc - supported Sampling Frequency Codes (SFCs)
  52  * @CIP_SFC_32000:   32,000 data blocks
  53  * @CIP_SFC_44100:   44,100 data blocks
  54  * @CIP_SFC_48000:   48,000 data blocks
  55  * @CIP_SFC_88200:   88,200 data blocks
  56  * @CIP_SFC_96000:   96,000 data blocks
  57  * @CIP_SFC_176400: 176,400 data blocks
  58  * @CIP_SFC_192000: 192,000 data blocks
  59  * @CIP_SFC_COUNT: the number of supported SFCs
  60  *
  61  * These values are used to show nominal Sampling Frequency Code in
  62  * Format Dependent Field (FDF) of AMDTP packet header. In IEC 61883-6:2002,
  63  * this code means the number of events per second. Actually the code
  64  * represents the number of data blocks transferred per second in an AMDTP
  65  * stream.
  66  *
  67  * In IEC 61883-6:2005, some extensions were added to support more types of
  68  * data such as 'One Bit LInear Audio', therefore the meaning of SFC became
  69  * different depending on the types.
  70  *
  71  * Currently our implementation is compatible with IEC 61883-6:2002.
  72  */
  73 enum cip_sfc {
  74         CIP_SFC_32000  = 0,
  75         CIP_SFC_44100  = 1,
  76         CIP_SFC_48000  = 2,
  77         CIP_SFC_88200  = 3,
  78         CIP_SFC_96000  = 4,
  79         CIP_SFC_176400 = 5,
  80         CIP_SFC_192000 = 6,
  81         CIP_SFC_COUNT
  82 };
  83
  84 struct fw_unit;
  85 struct fw_iso_context;
  86 struct snd_pcm_substream;
  87 struct snd_pcm_runtime;
  88
  89 enum amdtp_stream_direction {
  90         AMDTP_OUT_STREAM = 0,
  91         AMDTP_IN_STREAM
  92 };
  93
  94 struct amdtp_stream;
  95 typedef unsigned int (*amdtp_stream_process_data_blocks_t)(
  96                                                 struct amdtp_stream *s,
  97                                                 __be32 *buffer,
  98                                                 unsigned int data_blocks,
  99                                                 unsigned int *syt);
 100 struct amdtp_stream {
 101         struct fw_unit *unit;
 102         enum cip_flags flags;
 103         enum amdtp_stream_direction direction;
 104         struct mutex mutex;
 105
 106         /* For packet processing. */
 107         struct fw_iso_context *context;
 108         struct iso_packets_buffer buffer;
 109         int packet_index;
 110
 111         /* For CIP headers. */
 112         unsigned int source_node_id_field;
 113         unsigned int data_block_quadlets;
 114         unsigned int data_block_counter;
 115         unsigned int fmt;
 116         unsigned int fdf;
 117         /* quirk: fixed interval of dbc between previos/current packets. */
 118         unsigned int tx_dbc_interval;
 119         /* quirk: indicate the value of dbc field in a first packet. */
 120         unsigned int tx_first_dbc;
 121
 122         /* Internal flags. */
 123         enum cip_sfc sfc;
 124         unsigned int syt_interval;
 125         unsigned int transfer_delay;
 126         unsigned int data_block_state;
 127         unsigned int last_syt_offset;
 128         unsigned int syt_offset_state;
 129
 130         /* For a PCM substream processing. */
 131         struct snd_pcm_substream *pcm;
 132         struct tasklet_struct period_tasklet;
 133         unsigned int pcm_buffer_pointer;
 134         unsigned int pcm_period_pointer;
 135         bool pointer_flush;
 136
 137         /* To wait for first packet. */
 138         bool callbacked;
 139         wait_queue_head_t callback_wait;
 140         struct amdtp_stream *sync_slave;
 141
 142         /* For backends to process data blocks. */
 143         void *protocol;
 144         amdtp_stream_process_data_blocks_t process_data_blocks;
 145 };
 146
 147 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
 148                       enum amdtp_stream_direction dir, enum cip_flags flags,
 149                       unsigned int fmt,
 150                       amdtp_stream_process_data_blocks_t process_data_blocks,
 151                       unsigned int protocol_size);
 152 void amdtp_stream_destroy(struct amdtp_stream *s);
 153
 154 int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
 155                                 unsigned int data_block_quadlets);
 156 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
 157
 158 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
 159 void amdtp_stream_update(struct amdtp_stream *s);
 160 void amdtp_stream_stop(struct amdtp_stream *s);
 161
 162 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
 163                                         struct snd_pcm_runtime *runtime);
 164
 165 void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
 166 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
 167 void amdtp_stream_pcm_abort(struct amdtp_stream *s);
 168
 169 extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
 170 extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
 171
 172 /**
 173  * amdtp_stream_running - check stream is running or not
 174  * @s: the AMDTP stream
 175  *
 176  * If this function returns true, the stream is running.
 177  */
 178 static inline bool amdtp_stream_running(struct amdtp_stream *s)
 179 {
 180         return !IS_ERR(s->context);
 181 }
 182
 183 /**
 184  * amdtp_streaming_error - check for streaming error
 185  * @s: the AMDTP stream
 186  *
 187  * If this function returns true, the stream's packet queue has stopped due to
 188  * an asynchronous error.
 189  */
 190 static inline bool amdtp_streaming_error(struct amdtp_stream *s)
 191 {
 192         return s->packet_index < 0;
 193 }
 194
 195 /**
 196  * amdtp_stream_pcm_running - check PCM substream is running or not
 197  * @s: the AMDTP stream
 198  *
 199  * If this function returns true, PCM substream in the AMDTP stream is running.
 200  */
 201 static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
 202 {
 203         return !!s->pcm;
 204 }
 205
 206 /**
 207  * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
 208  * @s: the AMDTP stream
 209  * @pcm: the PCM device to be started, or %NULL to stop the current device
 210  *
 211  * Call this function on a running isochronous stream to enable the actual
 212  * transmission of PCM data.  This function should be called from the PCM
 213  * device's .trigger callback.
 214  */
 215 static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
 216                                             struct snd_pcm_substream *pcm)
 217 {
 218         ACCESS_ONCE(s->pcm) = pcm;
 219 }
 220
 221 static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
 222 {
 223         return sfc & 1;
 224 }
 225
 226 static inline void amdtp_stream_set_sync(enum cip_flags sync_mode,
 227                                          struct amdtp_stream *master,
 228                                          struct amdtp_stream *slave)
 229 {
 230         if (sync_mode == CIP_SYNC_TO_DEVICE) {
 231                 master->flags |= CIP_SYNC_TO_DEVICE;
 232                 slave->flags |= CIP_SYNC_TO_DEVICE;
 233                 master->sync_slave = slave;
 234         } else {
 235                 master->flags &= ~CIP_SYNC_TO_DEVICE;
 236                 slave->flags &= ~CIP_SYNC_TO_DEVICE;
 237                 master->sync_slave = NULL;
 238         }
 239
 240         slave->sync_slave = NULL;
 241 }
 242
 243 /**
 244  * amdtp_stream_wait_callback - sleep till callbacked or timeout
 245  * @s: the AMDTP stream
 246  * @timeout: msec till timeout
 247  *
 248  * If this function return false, the AMDTP stream should be stopped.
 249  */
 250 static inline bool amdtp_stream_wait_callback(struct amdtp_stream *s,
 251                                               unsigned int timeout)
 252 {
 253         return wait_event_timeout(s->callback_wait,
 254                                   s->callbacked == true,
 255                                   msecs_to_jiffies(timeout)) > 0;
 256 }
 257
 258 #endif