sound/firewire/amdtp-stream.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef SOUND_FIREWIRE_AMDTP_H_INCLUDED
   3 #define SOUND_FIREWIRE_AMDTP_H_INCLUDED
   4
   5 #include <linux/err.h>
   6 #include <linux/interrupt.h>
   7 #include <linux/mutex.h>
   8 #include <linux/sched.h>
   9 #include <sound/asound.h>
  10 #include "packets-buffer.h"
  11
  12 /**
  13  * enum cip_flags - describes details of the streaming protocol
  14  * @CIP_NONBLOCKING: In non-blocking mode, each packet contains
  15  *      sample_rate/8000 samples, with rounding up or down to adjust
  16  *      for clock skew and left-over fractional samples.  This should
  17  *      be used if supported by the device.
  18  * @CIP_BLOCKING: In blocking mode, each packet contains either zero or
  19  *      SYT_INTERVAL samples, with these two types alternating so that
  20  *      the overall sample rate comes out right.
  21  * @CIP_EMPTY_WITH_TAG0: Only for in-stream. Empty in-packets have TAG0.
  22  * @CIP_DBC_IS_END_EVENT: The value of dbc in an packet corresponds to the end
  23  * of event in the packet. Out of IEC 61883.
  24  * @CIP_WRONG_DBS: Only for in-stream. The value of dbs is wrong in in-packets.
  25  *      The value of data_block_quadlets is used instead of reported value.
  26  * @CIP_SKIP_DBC_ZERO_CHECK: Only for in-stream.  Packets with zero in dbc is
  27  *      skipped for detecting discontinuity.
  28  * @CIP_EMPTY_HAS_WRONG_DBC: Only for in-stream. The value of dbc in empty
  29  *      packet is wrong but the others are correct.
  30  * @CIP_JUMBO_PAYLOAD: Only for in-stream. The number of data blocks in an
  31  *      packet is larger than IEC 61883-6 defines. Current implementation
  32  *      allows 5 times as large as IEC 61883-6 defines.
  33  * @CIP_HEADER_WITHOUT_EOH: Only for in-stream. CIP Header doesn't include
  34  *      valid EOH.
  35  * @CIP_NO_HEADERS: a lack of headers in packets
  36  */
  37 enum cip_flags {
  38         CIP_NONBLOCKING         = 0x00,
  39         CIP_BLOCKING            = 0x01,
  40         CIP_EMPTY_WITH_TAG0     = 0x02,
  41         CIP_DBC_IS_END_EVENT    = 0x04,
  42         CIP_WRONG_DBS           = 0x08,
  43         CIP_SKIP_DBC_ZERO_CHECK = 0x10,
  44         CIP_EMPTY_HAS_WRONG_DBC = 0x20,
  45         CIP_JUMBO_PAYLOAD       = 0x40,
  46         CIP_HEADER_WITHOUT_EOH  = 0x80,
  47         CIP_NO_HEADER           = 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         int tag;
 111         int (*handle_packet)(struct amdtp_stream *s,
 112                         unsigned int payload_quadlets, unsigned int cycle,
 113                         unsigned int index);
 114         unsigned int max_payload_length;
 115
 116         /* For CIP headers. */
 117         unsigned int source_node_id_field;
 118         unsigned int data_block_quadlets;
 119         unsigned int data_block_counter;
 120         unsigned int sph;
 121         unsigned int fmt;
 122         unsigned int fdf;
 123         /* quirk: fixed interval of dbc between previos/current packets. */
 124         unsigned int tx_dbc_interval;
 125         /* quirk: indicate the value of dbc field in a first packet. */
 126         unsigned int tx_first_dbc;
 127
 128         /* Internal flags. */
 129         enum cip_sfc sfc;
 130         unsigned int syt_interval;
 131         unsigned int transfer_delay;
 132         unsigned int data_block_state;
 133         unsigned int last_syt_offset;
 134         unsigned int syt_offset_state;
 135
 136         /* For a PCM substream processing. */
 137         struct snd_pcm_substream *pcm;
 138         struct tasklet_struct period_tasklet;
 139         snd_pcm_uframes_t pcm_buffer_pointer;
 140         unsigned int pcm_period_pointer;
 141
 142         /* To wait for first packet. */
 143         bool callbacked;
 144         wait_queue_head_t callback_wait;
 145         u32 start_cycle;
 146
 147         /* For backends to process data blocks. */
 148         void *protocol;
 149         amdtp_stream_process_data_blocks_t process_data_blocks;
 150 };
 151
 152 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
 153                       enum amdtp_stream_direction dir, enum cip_flags flags,
 154                       unsigned int fmt,
 155                       amdtp_stream_process_data_blocks_t process_data_blocks,
 156                       unsigned int protocol_size);
 157 void amdtp_stream_destroy(struct amdtp_stream *s);
 158
 159 int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
 160                                 unsigned int data_block_quadlets);
 161 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
 162
 163 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
 164 void amdtp_stream_update(struct amdtp_stream *s);
 165 void amdtp_stream_stop(struct amdtp_stream *s);
 166
 167 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
 168                                         struct snd_pcm_runtime *runtime);
 169
 170 void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
 171 unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
 172 int amdtp_stream_pcm_ack(struct amdtp_stream *s);
 173 void amdtp_stream_pcm_abort(struct amdtp_stream *s);
 174
 175 extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
 176 extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
 177
 178 /**
 179  * amdtp_stream_running - check stream is running or not
 180  * @s: the AMDTP stream
 181  *
 182  * If this function returns true, the stream is running.
 183  */
 184 static inline bool amdtp_stream_running(struct amdtp_stream *s)
 185 {
 186         return !IS_ERR(s->context);
 187 }
 188
 189 /**
 190  * amdtp_streaming_error - check for streaming error
 191  * @s: the AMDTP stream
 192  *
 193  * If this function returns true, the stream's packet queue has stopped due to
 194  * an asynchronous error.
 195  */
 196 static inline bool amdtp_streaming_error(struct amdtp_stream *s)
 197 {
 198         return s->packet_index < 0;
 199 }
 200
 201 /**
 202  * amdtp_stream_pcm_running - check PCM substream is running or not
 203  * @s: the AMDTP stream
 204  *
 205  * If this function returns true, PCM substream in the AMDTP stream is running.
 206  */
 207 static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
 208 {
 209         return !!s->pcm;
 210 }
 211
 212 /**
 213  * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
 214  * @s: the AMDTP stream
 215  * @pcm: the PCM device to be started, or %NULL to stop the current device
 216  *
 217  * Call this function on a running isochronous stream to enable the actual
 218  * transmission of PCM data.  This function should be called from the PCM
 219  * device's .trigger callback.
 220  */
 221 static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
 222                                             struct snd_pcm_substream *pcm)
 223 {
 224         WRITE_ONCE(s->pcm, pcm);
 225 }
 226
 227 static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
 228 {
 229         return sfc & 1;
 230 }
 231
 232 /**
 233  * amdtp_stream_wait_callback - sleep till callbacked or timeout
 234  * @s: the AMDTP stream
 235  * @timeout: msec till timeout
 236  *
 237  * If this function return false, the AMDTP stream should be stopped.
 238  */
 239 static inline bool amdtp_stream_wait_callback(struct amdtp_stream *s,
 240                                               unsigned int timeout)
 241 {
 242         return wait_event_timeout(s->callback_wait,
 243                                   s->callbacked == true,
 244                                   msecs_to_jiffies(timeout)) > 0;
 245 }
 246
 247 #endif