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  */
  33 enum 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  */
  67 enum 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
  78 struct fw_unit;
  79 struct fw_iso_context;
  80 struct snd_pcm_substream;
  81 struct snd_pcm_runtime;
  82
  83 enum amdtp_stream_direction {
  84         AMDTP_OUT_STREAM = 0,
  85         AMDTP_IN_STREAM
  86 };
  87
  88 struct amdtp_stream;
  89 typedef 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);
  94 struct 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         snd_pcm_uframes_t 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
 139 int 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);
 144 void amdtp_stream_destroy(struct amdtp_stream *s);
 145
 146 int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
 147                                 unsigned int data_block_quadlets);
 148 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
 149
 150 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
 151 void amdtp_stream_update(struct amdtp_stream *s);
 152 void amdtp_stream_stop(struct amdtp_stream *s);
 153
 154 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
 155                                         struct snd_pcm_runtime *runtime);
 156
 157 void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
 158 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
 159 void amdtp_stream_pcm_abort(struct amdtp_stream *s);
 160
 161 extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
 162 extern 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  */
 170 static 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  */
 182 static 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  */
 193 static 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  */
 207 static 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
 213 static 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  */
 225 static 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