LXR linux/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 */
  37enum 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 */
  73enum 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
  84struct fw_unit;
  85struct fw_iso_context;
  86struct snd_pcm_substream;
  87struct snd_pcm_runtime;
  88
  89enum amdtp_stream_direction {
  90        AMDTP_OUT_STREAM = 0,
  91        AMDTP_IN_STREAM
  92};
  93
  94struct amdtp_stream;
  95typedef 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);
 100struct 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
 152int 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);
 157void amdtp_stream_destroy(struct amdtp_stream *s);
 158
 159int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
 160                                unsigned int data_block_quadlets);
 161unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
 162
 163int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);
 164void amdtp_stream_update(struct amdtp_stream *s);
 165void amdtp_stream_stop(struct amdtp_stream *s);
 166
 167int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
 168                                        struct snd_pcm_runtime *runtime);
 169
 170void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
 171unsigned long amdtp_stream_pcm_pointer(struct amdtp_stream *s);
 172int amdtp_stream_pcm_ack(struct amdtp_stream *s);
 173void amdtp_stream_pcm_abort(struct amdtp_stream *s);
 174
 175extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
 176extern 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 */
 184static 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 */
 196static 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 */
 207static 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 */
 221static 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
 227static 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 */
 239static 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
 248