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  */
  36 enum 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  */
  72 enum 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
  83 struct fw_unit;
  84 struct fw_iso_context;
  85 struct snd_pcm_substream;
  86 struct snd_pcm_runtime;
  87
  88 enum amdtp_stream_direction {
  89         AMDTP_OUT_STREAM = 0,
  90         AMDTP_IN_STREAM
  91 };
  92
  93 struct amdtp_stream;
  94 typedef 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);
  99 struct 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
 151 int 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);
 156 void amdtp_stream_destroy(struct amdtp_stream *s);
 157
 158 int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
 159                                 unsigned int data_block_quadlets);
 160 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
 161
 162 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
 163 void amdtp_stream_update(struct amdtp_stream *s);
 164 void amdtp_stream_stop(struct amdtp_stream *s);
 165
 166 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
 167                                         struct snd_pcm_runtime *runtime);
 168
 169 void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
 170 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
 171 int amdtp_stream_pcm_ack(struct amdtp_stream *s);
 172 void amdtp_stream_pcm_abort(struct amdtp_stream *s);
 173
 174 extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
 175 extern 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  */
 183 static 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  */
 195 static 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  */
 206 static 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  */
 220 static 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
 226 static 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  */
 238 static 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