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  */
  39 enum cip_flags {
  40         CIP_NONBLOCKING         = 0x00,
  41         CIP_BLOCKING            = 0x01,
  42         CIP_EMPTY_WITH_TAG0     = 0x02,
  43         CIP_DBC_IS_END_EVENT    = 0x04,
  44         CIP_WRONG_DBS           = 0x08,
  45         CIP_SKIP_DBC_ZERO_CHECK = 0x10,
  46         CIP_EMPTY_HAS_WRONG_DBC = 0x20,
  47         CIP_JUMBO_PAYLOAD       = 0x40,
  48         CIP_HEADER_WITHOUT_EOH  = 0x80,
  49         CIP_NO_HEADER           = 0x100,
  50         CIP_UNALIGHED_DBC       = 0x200,
  51 };
  52
  53 /**
  54  * enum cip_sfc - supported Sampling Frequency Codes (SFCs)
  55  * @CIP_SFC_32000:   32,000 data blocks
  56  * @CIP_SFC_44100:   44,100 data blocks
  57  * @CIP_SFC_48000:   48,000 data blocks
  58  * @CIP_SFC_88200:   88,200 data blocks
  59  * @CIP_SFC_96000:   96,000 data blocks
  60  * @CIP_SFC_176400: 176,400 data blocks
  61  * @CIP_SFC_192000: 192,000 data blocks
  62  * @CIP_SFC_COUNT: the number of supported SFCs
  63  *
  64  * These values are used to show nominal Sampling Frequency Code in
  65  * Format Dependent Field (FDF) of AMDTP packet header. In IEC 61883-6:2002,
  66  * this code means the number of events per second. Actually the code
  67  * represents the number of data blocks transferred per second in an AMDTP
  68  * stream.
  69  *
  70  * In IEC 61883-6:2005, some extensions were added to support more types of
  71  * data such as 'One Bit LInear Audio', therefore the meaning of SFC became
  72  * different depending on the types.
  73  *
  74  * Currently our implementation is compatible with IEC 61883-6:2002.
  75  */
  76 enum cip_sfc {
  77         CIP_SFC_32000  = 0,
  78         CIP_SFC_44100  = 1,
  79         CIP_SFC_48000  = 2,
  80         CIP_SFC_88200  = 3,
  81         CIP_SFC_96000  = 4,
  82         CIP_SFC_176400 = 5,
  83         CIP_SFC_192000 = 6,
  84         CIP_SFC_COUNT
  85 };
  86
  87 struct fw_unit;
  88 struct fw_iso_context;
  89 struct snd_pcm_substream;
  90 struct snd_pcm_runtime;
  91
  92 enum amdtp_stream_direction {
  93         AMDTP_OUT_STREAM = 0,
  94         AMDTP_IN_STREAM
  95 };
  96
  97 struct pkt_desc {
  98         u32 cycle;
  99         u32 syt;
 100         unsigned int data_blocks;
 101         unsigned int data_block_counter;
 102         __be32 *ctx_payload;
 103 };
 104
 105 struct amdtp_stream;
 106 typedef unsigned int (*amdtp_stream_process_ctx_payloads_t)(
 107                                                 struct amdtp_stream *s,
 108                                                 const struct pkt_desc *desc,
 109                                                 unsigned int packets,
 110                                                 struct snd_pcm_substream *pcm);
 111 struct amdtp_stream {
 112         struct fw_unit *unit;
 113         enum cip_flags flags;
 114         enum amdtp_stream_direction direction;
 115         struct mutex mutex;
 116
 117         /* For packet processing. */
 118         struct fw_iso_context *context;
 119         struct iso_packets_buffer buffer;
 120         unsigned int queue_size;
 121         int packet_index;
 122         struct pkt_desc *pkt_descs;
 123         int tag;
 124         union {
 125                 struct {
 126                         unsigned int ctx_header_size;
 127
 128                         // limit for payload of iso packet.
 129                         unsigned int max_ctx_payload_length;
 130
 131                         // For quirks of CIP headers.
 132                         // Fixed interval of dbc between previos/current
 133                         // packets.
 134                         unsigned int dbc_interval;
 135                 } tx;
 136                 struct {
 137                         // To calculate CIP data blocks and tstamp.
 138                         unsigned int transfer_delay;
 139                         unsigned int data_block_state;
 140                         unsigned int last_syt_offset;
 141                         unsigned int syt_offset_state;
 142
 143                         // To generate CIP header.
 144                         unsigned int fdf;
 145                         int syt_override;
 146
 147                         // To generate constant hardware IRQ.
 148                         unsigned int event_count;
 149                         unsigned int events_per_period;
 150                 } rx;
 151         } ctx_data;
 152
 153         /* For CIP headers. */
 154         unsigned int source_node_id_field;
 155         unsigned int data_block_quadlets;
 156         unsigned int data_block_counter;
 157         unsigned int sph;
 158         unsigned int fmt;
 159
 160         /* Internal flags. */
 161         enum cip_sfc sfc;
 162         unsigned int syt_interval;
 163
 164         /* For a PCM substream processing. */
 165         struct snd_pcm_substream *pcm;
 166         struct tasklet_struct period_tasklet;
 167         snd_pcm_uframes_t pcm_buffer_pointer;
 168         unsigned int pcm_period_pointer;
 169
 170         /* To wait for first packet. */
 171         bool callbacked;
 172         wait_queue_head_t callback_wait;
 173         u32 start_cycle;
 174
 175         /* For backends to process data blocks. */
 176         void *protocol;
 177         amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
 178
 179         // For domain.
 180         int channel;
 181         int speed;
 182         struct list_head list;
 183 };
 184
 185 int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
 186                       enum amdtp_stream_direction dir, enum cip_flags flags,
 187                       unsigned int fmt,
 188                       amdtp_stream_process_ctx_payloads_t process_ctx_payloads,
 189                       unsigned int protocol_size);
 190 void amdtp_stream_destroy(struct amdtp_stream *s);
 191
 192 int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
 193                                 unsigned int data_block_quadlets);
 194 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
 195
 196 void amdtp_stream_update(struct amdtp_stream *s);
 197
 198 int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
 199                                         struct snd_pcm_runtime *runtime);
 200
 201 void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
 202 void amdtp_stream_pcm_abort(struct amdtp_stream *s);
 203
 204 extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
 205 extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
 206
 207 /**
 208  * amdtp_stream_running - check stream is running or not
 209  * @s: the AMDTP stream
 210  *
 211  * If this function returns true, the stream is running.
 212  */
 213 static inline bool amdtp_stream_running(struct amdtp_stream *s)
 214 {
 215         return !IS_ERR(s->context);
 216 }
 217
 218 /**
 219  * amdtp_streaming_error - check for streaming error
 220  * @s: the AMDTP stream
 221  *
 222  * If this function returns true, the stream's packet queue has stopped due to
 223  * an asynchronous error.
 224  */
 225 static inline bool amdtp_streaming_error(struct amdtp_stream *s)
 226 {
 227         return s->packet_index < 0;
 228 }
 229
 230 /**
 231  * amdtp_stream_pcm_running - check PCM substream is running or not
 232  * @s: the AMDTP stream
 233  *
 234  * If this function returns true, PCM substream in the AMDTP stream is running.
 235  */
 236 static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
 237 {
 238         return !!s->pcm;
 239 }
 240
 241 /**
 242  * amdtp_stream_pcm_trigger - start/stop playback from a PCM device
 243  * @s: the AMDTP stream
 244  * @pcm: the PCM device to be started, or %NULL to stop the current device
 245  *
 246  * Call this function on a running isochronous stream to enable the actual
 247  * transmission of PCM data.  This function should be called from the PCM
 248  * device's .trigger callback.
 249  */
 250 static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
 251                                             struct snd_pcm_substream *pcm)
 252 {
 253         WRITE_ONCE(s->pcm, pcm);
 254 }
 255
 256 static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
 257 {
 258         return sfc & 1;
 259 }
 260
 261 /**
 262  * amdtp_stream_wait_callback - sleep till callbacked or timeout
 263  * @s: the AMDTP stream
 264  * @timeout: msec till timeout
 265  *
 266  * If this function return false, the AMDTP stream should be stopped.
 267  */
 268 static inline bool amdtp_stream_wait_callback(struct amdtp_stream *s,
 269                                               unsigned int timeout)
 270 {
 271         return wait_event_timeout(s->callback_wait,
 272                                   s->callbacked == true,
 273                                   msecs_to_jiffies(timeout)) > 0;
 274 }
 275
 276 struct amdtp_domain {
 277         struct list_head streams;
 278
 279         unsigned int events_per_period;
 280         unsigned int events_per_buffer;
 281
 282         struct amdtp_stream *irq_target;
 283 };
 284
 285 int amdtp_domain_init(struct amdtp_domain *d);
 286 void amdtp_domain_destroy(struct amdtp_domain *d);
 287
 288 int amdtp_domain_add_stream(struct amdtp_domain *d, struct amdtp_stream *s,
 289                             int channel, int speed);
 290
 291 int amdtp_domain_start(struct amdtp_domain *d, unsigned int ir_delay_cycle);
 292 void amdtp_domain_stop(struct amdtp_domain *d);
 293
 294 static inline int amdtp_domain_set_events_per_period(struct amdtp_domain *d,
 295                                                 unsigned int events_per_period,
 296                                                 unsigned int events_per_buffer)
 297 {
 298         d->events_per_period = events_per_period;
 299         d->events_per_buffer = events_per_buffer;
 300
 301         return 0;
 302 }
 303
 304 unsigned long amdtp_domain_stream_pcm_pointer(struct amdtp_domain *d,
 305                                               struct amdtp_stream *s);
 306 int amdtp_domain_stream_pcm_ack(struct amdtp_domain *d, struct amdtp_stream *s);
 307
 308 #endif