sound/firewire/tascam/tascam-transaction.c

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This source file includes following definitions.
calculate_message_bytes
fill_message
async_midi_port_callback
midi_port_work
snd_fw_async_midi_port_init
handle_midi_tx
snd_tscm_transaction_register
snd_tscm_transaction_reregister
snd_tscm_transaction_unregister
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * tascam-transaction.c - a part of driver for TASCAM FireWire series
   4  *
   5  * Copyright (c) 2015 Takashi Sakamoto
   6  */
   7 
   8 #include "tascam.h"
   9 
  10 /*
  11  * When return minus value, given argument is not MIDI status.
  12  * When return 0, given argument is a beginning of system exclusive.
  13  * When return the others, given argument is MIDI data.
  14  */
  15 static inline int calculate_message_bytes(u8 status)
  16 {
  17         switch (status) {
  18         case 0xf6:      /* Tune request. */
  19         case 0xf8:      /* Timing clock. */
  20         case 0xfa:      /* Start. */
  21         case 0xfb:      /* Continue. */
  22         case 0xfc:      /* Stop. */
  23         case 0xfe:      /* Active sensing. */
  24         case 0xff:      /* System reset. */
  25                 return 1;
  26         case 0xf1:      /* MIDI time code quarter frame. */
  27         case 0xf3:      /* Song select. */
  28                 return 2;
  29         case 0xf2:      /* Song position pointer. */
  30                 return 3;
  31         case 0xf0:      /* Exclusive. */
  32                 return 0;
  33         case 0xf7:      /* End of exclusive. */
  34                 break;
  35         case 0xf4:      /* Undefined. */
  36         case 0xf5:      /* Undefined. */
  37         case 0xf9:      /* Undefined. */
  38         case 0xfd:      /* Undefined. */
  39                 break;
  40         default:
  41                 switch (status & 0xf0) {
  42                 case 0x80:      /* Note on. */
  43                 case 0x90:      /* Note off. */
  44                 case 0xa0:      /* Polyphonic key pressure. */
  45                 case 0xb0:      /* Control change and Mode change. */
  46                 case 0xe0:      /* Pitch bend change. */
  47                         return 3;
  48                 case 0xc0:      /* Program change. */
  49                 case 0xd0:      /* Channel pressure. */
  50                         return 2;
  51                 default:
  52                 break;
  53                 }
  54         break;
  55         }
  56 
  57         return -EINVAL;
  58 }
  59 
  60 static int fill_message(struct snd_fw_async_midi_port *port,
  61                         struct snd_rawmidi_substream *substream)
  62 {
  63         int i, len, consume;
  64         u8 *label, *msg;
  65         u8 status;
  66 
  67         /* The first byte is used for label, the rest for MIDI bytes. */
  68         label = port->buf;
  69         msg = port->buf + 1;
  70 
  71         consume = snd_rawmidi_transmit_peek(substream, msg, 3);
  72         if (consume == 0)
  73                 return 0;
  74 
  75         /* On exclusive message. */
  76         if (port->on_sysex) {
  77                 /* Seek the end of exclusives. */
  78                 for (i = 0; i < consume; ++i) {
  79                         if (msg[i] == 0xf7) {
  80                                 port->on_sysex = false;
  81                                 break;
  82                         }
  83                 }
  84 
  85                 /* At the end of exclusive message, use label 0x07. */
  86                 if (!port->on_sysex) {
  87                         consume = i + 1;
  88                         *label = (substream->number << 4) | 0x07;
  89                 /* During exclusive message, use label 0x04. */
  90                 } else if (consume == 3) {
  91                         *label = (substream->number << 4) | 0x04;
  92                 /* We need to fill whole 3 bytes. Go to next change. */
  93                 } else {
  94                         return 0;
  95                 }
  96 
  97                 len = consume;
  98         } else {
  99                 /* The beginning of exclusives. */
 100                 if (msg[0] == 0xf0) {
 101                         /* Transfer it in next chance in another condition. */
 102                         port->on_sysex = true;
 103                         return 0;
 104                 } else {
 105                         /* On running-status. */
 106                         if ((msg[0] & 0x80) != 0x80)
 107                                 status = port->running_status;
 108                         else
 109                                 status = msg[0];
 110 
 111                         /* Calculate consume bytes. */
 112                         len = calculate_message_bytes(status);
 113                         if (len <= 0)
 114                                 return 0;
 115 
 116                         /* On running-status. */
 117                         if ((msg[0] & 0x80) != 0x80) {
 118                                 /* Enough MIDI bytes were not retrieved. */
 119                                 if (consume < len - 1)
 120                                         return 0;
 121                                 consume = len - 1;
 122 
 123                                 msg[2] = msg[1];
 124                                 msg[1] = msg[0];
 125                                 msg[0] = port->running_status;
 126                         } else {
 127                                 /* Enough MIDI bytes were not retrieved. */
 128                                 if (consume < len)
 129                                         return 0;
 130                                 consume = len;
 131 
 132                                 port->running_status = msg[0];
 133                         }
 134                 }
 135 
 136                 *label = (substream->number << 4) | (msg[0] >> 4);
 137         }
 138 
 139         if (len > 0 && len < 3)
 140                 memset(msg + len, 0, 3 - len);
 141 
 142         return consume;
 143 }
 144 
 145 static void async_midi_port_callback(struct fw_card *card, int rcode,
 146                                      void *data, size_t length,
 147                                      void *callback_data)
 148 {
 149         struct snd_fw_async_midi_port *port = callback_data;
 150         struct snd_rawmidi_substream *substream = READ_ONCE(port->substream);
 151 
 152         /* This port is closed. */
 153         if (substream == NULL)
 154                 return;
 155 
 156         if (rcode == RCODE_COMPLETE)
 157                 snd_rawmidi_transmit_ack(substream, port->consume_bytes);
 158         else if (!rcode_is_permanent_error(rcode))
 159                 /* To start next transaction immediately for recovery. */
 160                 port->next_ktime = 0;
 161         else
 162                 /* Don't continue processing. */
 163                 port->error = true;
 164 
 165         port->idling = true;
 166 
 167         if (!snd_rawmidi_transmit_empty(substream))
 168                 schedule_work(&port->work);
 169 }
 170 
 171 static void midi_port_work(struct work_struct *work)
 172 {
 173         struct snd_fw_async_midi_port *port =
 174                         container_of(work, struct snd_fw_async_midi_port, work);
 175         struct snd_rawmidi_substream *substream = READ_ONCE(port->substream);
 176         int generation;
 177 
 178         /* Under transacting or error state. */
 179         if (!port->idling || port->error)
 180                 return;
 181 
 182         /* Nothing to do. */
 183         if (substream == NULL || snd_rawmidi_transmit_empty(substream))
 184                 return;
 185 
 186         /* Do it in next chance. */
 187         if (ktime_after(port->next_ktime, ktime_get())) {
 188                 schedule_work(&port->work);
 189                 return;
 190         }
 191 
 192         /*
 193          * Fill the buffer. The callee must use snd_rawmidi_transmit_peek().
 194          * Later, snd_rawmidi_transmit_ack() is called.
 195          */
 196         memset(port->buf, 0, 4);
 197         port->consume_bytes = fill_message(port, substream);
 198         if (port->consume_bytes <= 0) {
 199                 /* Do it in next chance, immediately. */
 200                 if (port->consume_bytes == 0) {
 201                         port->next_ktime = 0;
 202                         schedule_work(&port->work);
 203                 } else {
 204                         /* Fatal error. */
 205                         port->error = true;
 206                 }
 207                 return;
 208         }
 209 
 210         /* Set interval to next transaction. */
 211         port->next_ktime = ktime_add_ns(ktime_get(),
 212                                 port->consume_bytes * 8 * NSEC_PER_SEC / 31250);
 213 
 214         /* Start this transaction. */
 215         port->idling = false;
 216 
 217         /*
 218          * In Linux FireWire core, when generation is updated with memory
 219          * barrier, node id has already been updated. In this module, After
 220          * this smp_rmb(), load/store instructions to memory are completed.
 221          * Thus, both of generation and node id are available with recent
 222          * values. This is a light-serialization solution to handle bus reset
 223          * events on IEEE 1394 bus.
 224          */
 225         generation = port->parent->generation;
 226         smp_rmb();
 227 
 228         fw_send_request(port->parent->card, &port->transaction,
 229                         TCODE_WRITE_QUADLET_REQUEST,
 230                         port->parent->node_id, generation,
 231                         port->parent->max_speed,
 232                         TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_RX_QUAD,
 233                         port->buf, 4, async_midi_port_callback,
 234                         port);
 235 }
 236 
 237 void snd_fw_async_midi_port_init(struct snd_fw_async_midi_port *port)
 238 {
 239         port->idling = true;
 240         port->error = false;
 241         port->running_status = 0;
 242         port->on_sysex = false;
 243 }
 244 
 245 static void handle_midi_tx(struct fw_card *card, struct fw_request *request,
 246                            int tcode, int destination, int source,
 247                            int generation, unsigned long long offset,
 248                            void *data, size_t length, void *callback_data)
 249 {
 250         struct snd_tscm *tscm = callback_data;
 251         u32 *buf = (u32 *)data;
 252         unsigned int messages;
 253         unsigned int i;
 254         unsigned int port;
 255         struct snd_rawmidi_substream *substream;
 256         u8 *b;
 257         int bytes;
 258 
 259         if (offset != tscm->async_handler.offset)
 260                 goto end;
 261 
 262         messages = length / 8;
 263         for (i = 0; i < messages; i++) {
 264                 b = (u8 *)(buf + i * 2);
 265 
 266                 port = b[0] >> 4;
 267                 /* TODO: support virtual MIDI ports. */
 268                 if (port >= tscm->spec->midi_capture_ports)
 269                         goto end;
 270 
 271                 /* Assume the message length. */
 272                 bytes = calculate_message_bytes(b[1]);
 273                 /* On MIDI data or exclusives. */
 274                 if (bytes <= 0) {
 275                         /* Seek the end of exclusives. */
 276                         for (bytes = 1; bytes < 4; bytes++) {
 277                                 if (b[bytes] == 0xf7)
 278                                         break;
 279                         }
 280                         if (bytes == 4)
 281                                 bytes = 3;
 282                 }
 283 
 284                 substream = READ_ONCE(tscm->tx_midi_substreams[port]);
 285                 if (substream != NULL)
 286                         snd_rawmidi_receive(substream, b + 1, bytes);
 287         }
 288 end:
 289         fw_send_response(card, request, RCODE_COMPLETE);
 290 }
 291 
 292 int snd_tscm_transaction_register(struct snd_tscm *tscm)
 293 {
 294         static const struct fw_address_region resp_register_region = {
 295                 .start  = 0xffffe0000000ull,
 296                 .end    = 0xffffe000ffffull,
 297         };
 298         unsigned int i;
 299         int err;
 300 
 301         /*
 302          * Usually, two quadlets are transferred by one transaction. The first
 303          * quadlet has MIDI messages, the rest includes timestamp.
 304          * Sometimes, 8 set of the data is transferred by a block transaction.
 305          */
 306         tscm->async_handler.length = 8 * 8;
 307         tscm->async_handler.address_callback = handle_midi_tx;
 308         tscm->async_handler.callback_data = tscm;
 309 
 310         err = fw_core_add_address_handler(&tscm->async_handler,
 311                                           &resp_register_region);
 312         if (err < 0)
 313                 return err;
 314 
 315         err = snd_tscm_transaction_reregister(tscm);
 316         if (err < 0)
 317                 goto error;
 318 
 319         for (i = 0; i < TSCM_MIDI_OUT_PORT_MAX; i++) {
 320                 tscm->out_ports[i].parent = fw_parent_device(tscm->unit);
 321                 tscm->out_ports[i].next_ktime = 0;
 322                 INIT_WORK(&tscm->out_ports[i].work, midi_port_work);
 323         }
 324 
 325         return err;
 326 error:
 327         fw_core_remove_address_handler(&tscm->async_handler);
 328         tscm->async_handler.callback_data = NULL;
 329         return err;
 330 }
 331 
 332 /* At bus reset, these registers are cleared. */
 333 int snd_tscm_transaction_reregister(struct snd_tscm *tscm)
 334 {
 335         struct fw_device *device = fw_parent_device(tscm->unit);
 336         __be32 reg;
 337         int err;
 338 
 339         /* Register messaging address. Block transaction is not allowed. */
 340         reg = cpu_to_be32((device->card->node_id << 16) |
 341                           (tscm->async_handler.offset >> 32));
 342         err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 343                                  TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ADDR_HI,
 344                                  &reg, sizeof(reg), 0);
 345         if (err < 0)
 346                 return err;
 347 
 348         reg = cpu_to_be32(tscm->async_handler.offset);
 349         err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 350                                  TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ADDR_LO,
 351                                  &reg, sizeof(reg), 0);
 352         if (err < 0)
 353                 return err;
 354 
 355         /* Turn on messaging. */
 356         reg = cpu_to_be32(0x00000001);
 357         err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 358                                   TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ON,
 359                                   &reg, sizeof(reg), 0);
 360         if (err < 0)
 361                 return err;
 362 
 363         /* Turn on FireWire LED. */
 364         reg = cpu_to_be32(0x0001008e);
 365         return snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 366                                   TSCM_ADDR_BASE + TSCM_OFFSET_LED_POWER,
 367                                   &reg, sizeof(reg), 0);
 368 }
 369 
 370 void snd_tscm_transaction_unregister(struct snd_tscm *tscm)
 371 {
 372         __be32 reg;
 373 
 374         if (tscm->async_handler.callback_data == NULL)
 375                 return;
 376 
 377         /* Turn off FireWire LED. */
 378         reg = cpu_to_be32(0x0000008e);
 379         snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 380                            TSCM_ADDR_BASE + TSCM_OFFSET_LED_POWER,
 381                            &reg, sizeof(reg), 0);
 382 
 383         /* Turn off messaging. */
 384         reg = cpu_to_be32(0x00000000);
 385         snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 386                            TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ON,
 387                            &reg, sizeof(reg), 0);
 388 
 389         /* Unregister the address. */
 390         snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 391                            TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ADDR_HI,
 392                            &reg, sizeof(reg), 0);
 393         snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 394                            TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ADDR_LO,
 395                            &reg, sizeof(reg), 0);
 396 
 397         fw_core_remove_address_handler(&tscm->async_handler);
 398         tscm->async_handler.callback_data = NULL;
 399 }
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root/sound/firewire/tascam/tascam-transaction.c

DEFINITIONS
