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