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  * @CIP_UNALIGHED_DBC: Only for in-stream. The value of dbc is not alighed to
  37  *      the value of current SYT_INTERVAL; e.g. initial value is not zero.
  38  * @CIP_UNAWARE_SYT: For outgoing packet, the value in SYT field of CIP is 0xffff.
  39  *      For incoming packet, the value in SYT field of CIP is not handled.
  40  * @CIP_DBC_IS_PAYLOAD_QUADLETS: Available for incoming packet, and only effective with
  41  *      CIP_DBC_IS_END_EVENT flag. The value of dbc field is the number of accumulated quadlets
  42  *      in CIP payload, instead of the number of accumulated data blocks.
  43  */
  44 enum cip_flags {
  45         CIP_NONBLOCKING         = 0x00,
  46         CIP_BLOCKING            = 0x01,
  47         CIP_EMPTY_WITH_TAG0     = 0x02,
  48         CIP_DBC_IS_END_EVENT    = 0x04,
  49         CIP_WRONG_DBS           = 0x08,
  50         CIP_SKIP_DBC_ZERO_CHECK = 0x10,
  51         CIP_EMPTY_HAS_WRONG_DBC = 0x20,
  52         CIP_JUMBO_PAYLOAD       = 0x40,
  53         CIP_HEADER_WITHOUT_EOH  = 0x80,
  54         CIP_NO_HEADER           = 0x100,
  55         CIP_UNALIGHED_DBC       = 0x200,
  56         CIP_UNAWARE_SYT         = 0x400,
  57         CIP_DBC_IS_PAYLOAD_QUADLETS = 0x800,
  58 };
  59
  60 /**
  61  * enum cip_sfc - supported Sampling Frequency Codes (SFCs)
  62  * @CIP_SFC_32000:   32,000 data blocks
  63  * @CIP_SFC_44100:   44,100 data blocks
  64  * @CIP_SFC_48000:   48,000 data blocks
  65  * @CIP_SFC_88200:   88,200 data blocks
  66  * @CIP_SFC_96000:   96,000 data blocks
  67  * @CIP_SFC_176400: 176,400 data blocks
  68  * @CIP_SFC_192000: 192,000 data blocks
  69  * @CIP_SFC_COUNT: the number of supported SFCs
  70  *
  71  * These values are used to show nominal Sampling Frequency Code in
  72  * Format Dependent Field (FDF) of AMDTP packet header. In IEC 61883-6:2002,
  73  * this code means the number of events per second. Actually the code
  74  * represents the number of data blocks transferred per second in an AMDTP
  75  * stream.
  76  *
  77  * In IEC 61883-6:2005, some extensions were added to support more types of
  78  * data such as 'One Bit LInear Audio', therefore the meaning of SFC became
  79  * different depending on the types.
  80  *
  81  * Currently our implementation is compatible with IEC 61883-6:2002.
  82  */
  83 enum cip_sfc {
  84         CIP_SFC_32000  = 0,
  85         CIP_SFC_44100  = 1,
  86         CIP_SFC_48000  = 2,
  87         CIP_SFC_88200  = 3,
  88         CIP_SFC_96000  = 4,
  89         CIP_SFC_176400 = 5,
  90         CIP_SFC_192000 = 6,
  91         CIP_SFC_COUNT
  92 };
  93
  94 struct fw_unit;
  95 struct fw_iso_context;
  96 struct snd_pcm_substream;
  97 struct snd_pcm_runtime;
  98
  99 enum amdtp_stream_direction {
 100         AMDTP_OUT_STREAM = 0,
 101         AMDTP_IN_STREAM
 102 };
 103
 104 struct pkt_desc {
 105         u32 cycle;
 106         u32 syt;
 107         unsigned int data_blocks;
 108         unsigned int data_block_counter;
 109         __be32 *ctx_payload;
 110         struct list_head link;
 111 };
 112
 113 struct amdtp_stream;
 114 typedef void (*amdtp_stream_process_ctx_payloads_t)(struct amdtp_stream *s,
 115                                                     const struct pkt_desc *desc,
 116                                                     unsigned int count,
 117                                                     struct snd_pcm_substream *pcm);
 118
 119 struct amdtp_domain;
 120 struct amdtp_stream {
 121         struct fw_unit *unit;
 122         // The combination of cip_flags enumeration-constants.
 123         unsigned int flags;
 124         enum amdtp_stream_direction direction;
 125         struct mutex mutex;
 126
 127         /* For packet processing. */
 128         struct fw_iso_context *context;
 129         struct iso_packets_buffer buffer;
 130         unsigned int queue_size;
 131         int packet_index;
 132         struct pkt_desc *packet_descs;
 133         struct list_head packet_descs_list;
 134         struct pkt_desc *packet_descs_cursor;
 135         int tag;
 136         union {
 137                 struct {
 138                         unsigned int ctx_header_size;
 139
 140                         // limit for payload of iso packet.
 141                         unsigned int max_ctx_payload_length;
 142
 143                         // For quirks of CIP headers.
 144                         // Fixed interval of dbc between previos/current
 145                         // packets.
 146                         unsigned int dbc_interval;
 147
 148                         // The device starts multiplexing events to the packet.
 149                         bool event_starts;
 150
 151                         struct {
 152                                 struct seq_desc *descs;
 153                                 unsigned int size;
 154                                 unsigned int pos;
 155                         } cache;
 156                 } tx;
 157                 struct {
 158                         // To generate CIP header.
 159                         unsigned int fdf;
 160
 161                         // To generate constant hardware IRQ.
 162                         unsigned int event_count;
 163
 164                         // To calculate CIP data blocks and tstamp.
 165                         struct {
 166                                 struct seq_desc *descs;
 167                                 unsigned int size;
 168                                 unsigned int pos;
 169                         } seq;
 170
 171                         unsigned int data_block_state;
 172                         unsigned int syt_offset_state;
 173                         unsigned int last_syt_offset;
 174
 175                         struct amdtp_stream *replay_target;
 176                         unsigned int cache_pos;
 177                 } rx;
 178         } ctx_data;
 179
 180         /* For CIP headers. */
 181         unsigned int source_node_id_field;
 182         unsigned int data_block_quadlets;
 183         unsigned int data_block_counter;
 184         unsigned int sph;
 185         unsigned int fmt;
 186
 187         // Internal flags.
 188         unsigned int transfer_delay;
 189         enum cip_sfc sfc;
 190         unsigned int syt_interval;
 191
 192         /* For a PCM substream processing. */
 193         struct snd_pcm_substream *pcm;
 194         struct work_struct period_work;
 195         snd_pcm_uframes_t pcm_buffer_pointer;
 196         unsigned int pcm_period_pointer;
 197         unsigned int pcm_frame_multiplier;
 198
 199         // To start processing content of packets at the same cycle in several contexts for
 200         // each direction.
 201         bool ready_processing;
 202         wait_queue_head_t ready_wait;
 203         unsigned int next_cycle;
 204
 205         /* For backends to process data blocks. */
 206         void *protocol;
 207         amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
 208
 209         // For domain.
 210         int channel;
 211         int speed;
 212         struct list_head list;
 213         struct amdtp_domain *domain;
 214 };
 215
 216 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
 217                       enum amdtp_stream_direction dir, unsigned int flags,
 218                       unsigned int fmt,
 219                       amdtp_stream_process_ctx_payloads_t process_ctx_payloads,
 220                       unsigned int protocol_size);
 221 void amdtp_stream_destroy(struct amdtp_stream *s);
 222
 223 int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
 224                                 unsigned int data_block_quadlets, unsigned int pcm_frame_multiplier);
 225 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
 226
 227 void amdtp_stream_update(struct amdtp_stream *s);
 228
 229 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
 230                                         struct snd_pcm_runtime *runtime);
 231
 232 void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
 233 void amdtp_stream_pcm_abort(struct amdtp_stream *s);
 234
 235 extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
 236 extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
 237
 238 /**
 239  * amdtp_stream_running - check stream is running or not
 240  * @s: the AMDTP stream
 241  *
 242  * If this function returns true, the stream is running.
 243  */
 244 static inline bool amdtp_stream_running(struct amdtp_stream *s)
 245 {
 246         return !IS_ERR(s->context);
 247 }
 248
 249 /**
 250  * amdtp_streaming_error - check for streaming error
 251  * @s: the AMDTP stream
 252  *
 253  * If this function returns true, the stream's packet queue has stopped due to
 254  * an asynchronous error.
 255  */
 256 static inline bool amdtp_streaming_error(struct amdtp_stream *s)
 257 {
 258         return s->packet_index < 0;
 259 }
 260
 261 /**
 262  * amdtp_stream_pcm_running - check PCM substream is running or not
 263  * @s: the AMDTP stream
 264  *
 265  * If this function returns true, PCM substream in the AMDTP stream is running.
 266  */
 267 static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
 268 {
 269         return !!s->pcm;
 270 }
 271
 272 /**
 273  * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
 274  * @s: the AMDTP stream
 275  * @pcm: the PCM device to be started, or %NULL to stop the current device
 276  *
 277  * Call this function on a running isochronous stream to enable the actual
 278  * transmission of PCM data.  This function should be called from the PCM
 279  * device's .trigger callback.
 280  */
 281 static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
 282                                             struct snd_pcm_substream *pcm)
 283 {
 284         WRITE_ONCE(s->pcm, pcm);
 285 }
 286
 287 /**
 288  * amdtp_stream_next_packet_desc - retrieve next descriptor for amdtp packet.
 289  * @s: the AMDTP stream
 290  * @desc: the descriptor of packet
 291  *
 292  * This macro computes next descriptor so that the list of descriptors behaves circular queue.
 293  */
 294 #define amdtp_stream_next_packet_desc(s, desc) \
 295         list_next_entry_circular(desc, &s->packet_descs_list, link)
 296
 297 static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
 298 {
 299         return sfc & 1;
 300 }
 301
 302 struct seq_desc {
 303         unsigned int syt_offset;
 304         unsigned int data_blocks;
 305 };
 306
 307 struct amdtp_domain {
 308         struct list_head streams;
 309
 310         unsigned int events_per_period;
 311         unsigned int events_per_buffer;
 312
 313         struct amdtp_stream *irq_target;
 314
 315         struct {
 316                 unsigned int tx_init_skip;
 317                 unsigned int tx_start;
 318                 unsigned int rx_start;
 319         } processing_cycle;
 320
 321         struct {
 322                 bool enable:1;
 323                 bool on_the_fly:1;
 324         } replay;
 325 };
 326
 327 int amdtp_domain_init(struct amdtp_domain *d);
 328 void amdtp_domain_destroy(struct amdtp_domain *d);
 329
 330 int amdtp_domain_add_stream(struct amdtp_domain *d, struct amdtp_stream *s,
 331                             int channel, int speed);
 332
 333 int amdtp_domain_start(struct amdtp_domain *d, unsigned int tx_init_skip_cycles, bool replay_seq,
 334                        bool replay_on_the_fly);
 335 void amdtp_domain_stop(struct amdtp_domain *d);
 336
 337 static inline int amdtp_domain_set_events_per_period(struct amdtp_domain *d,
 338                                                 unsigned int events_per_period,
 339                                                 unsigned int events_per_buffer)
 340 {
 341         d->events_per_period = events_per_period;
 342         d->events_per_buffer = events_per_buffer;
 343
 344         return 0;
 345 }
 346
 347 unsigned long amdtp_domain_stream_pcm_pointer(struct amdtp_domain *d,
 348                                               struct amdtp_stream *s);
 349 int amdtp_domain_stream_pcm_ack(struct amdtp_domain *d, struct amdtp_stream *s);
 350
 351 /**
 352  * amdtp_domain_wait_ready - sleep till being ready to process packets or timeout
 353  * @d: the AMDTP domain
 354  * @timeout_ms: msec till timeout
 355  *
 356  * If this function return false, the AMDTP domain should be stopped.
 357  */
 358 static inline bool amdtp_domain_wait_ready(struct amdtp_domain *d, unsigned int timeout_ms)
 359 {
 360         struct amdtp_stream *s;
 361
 362         list_for_each_entry(s, &d->streams, list) {
 363                 unsigned int j = msecs_to_jiffies(timeout_ms);
 364
 365                 if (wait_event_interruptible_timeout(s->ready_wait, s->ready_processing, j) <= 0)
 366                         return false;
 367         }
 368
 369         return true;
 370 }
 371
 372 #endif