sound/firewire/tascam/tascam-transaction.c

   1 /*
   2  * tascam-transaction.c - a part of driver for TASCAM FireWire series
   3  *
   4  * Copyright (c) 2015 Takashi Sakamoto
   5  *
   6  * Licensed under the terms of the GNU General Public License, version 2.
   7  */
   8
   9 #include "tascam.h"
  10
  11 /*
  12  * When return minus value, given argument is not MIDI status.
  13  * When return 0, given argument is a beginning of system exclusive.
  14  * When return the others, given argument is MIDI data.
  15  */
  16 static inline int calculate_message_bytes(u8 status)
  17 {
  18         switch (status) {
  19         case 0xf6:      /* Tune request. */
  20         case 0xf8:      /* Timing clock. */
  21         case 0xfa:      /* Start. */
  22         case 0xfb:      /* Continue. */
  23         case 0xfc:      /* Stop. */
  24         case 0xfe:      /* Active sensing. */
  25         case 0xff:      /* System reset. */
  26                 return 1;
  27         case 0xf1:      /* MIDI time code quarter frame. */
  28         case 0xf3:      /* Song select. */
  29                 return 2;
  30         case 0xf2:      /* Song position pointer. */
  31                 return 3;
  32         case 0xf0:      /* Exclusive. */
  33                 return 0;
  34         case 0xf7:      /* End of exclusive. */
  35                 break;
  36         case 0xf4:      /* Undefined. */
  37         case 0xf5:      /* Undefined. */
  38         case 0xf9:      /* Undefined. */
  39         case 0xfd:      /* Undefined. */
  40                 break;
  41         default:
  42                 switch (status & 0xf0) {
  43                 case 0x80:      /* Note on. */
  44                 case 0x90:      /* Note off. */
  45                 case 0xa0:      /* Polyphonic key pressure. */
  46                 case 0xb0:      /* Control change and Mode change. */
  47                 case 0xe0:      /* Pitch bend change. */
  48                         return 3;
  49                 case 0xc0:      /* Program change. */
  50                 case 0xd0:      /* Channel pressure. */
  51                         return 2;
  52                 default:
  53                 break;
  54                 }
  55         break;
  56         }
  57
  58         return -EINVAL;
  59 }
  60
  61 static int fill_message(struct snd_fw_async_midi_port *port,
  62                         struct snd_rawmidi_substream *substream)
  63 {
  64         int i, len, consume;
  65         u8 *label, *msg;
  66         u8 status;
  67
  68         /* The first byte is used for label, the rest for MIDI bytes. */
  69         label = port->buf;
  70         msg = port->buf + 1;
  71
  72         consume = snd_rawmidi_transmit_peek(substream, msg, 3);
  73         if (consume == 0)
  74                 return 0;
  75
  76         /* On exclusive message. */
  77         if (port->on_sysex) {
  78                 /* Seek the end of exclusives. */
  79                 for (i = 0; i < consume; ++i) {
  80                         if (msg[i] == 0xf7) {
  81                                 port->on_sysex = false;
  82                                 break;
  83                         }
  84                 }
  85
  86                 /* At the end of exclusive message, use label 0x07. */
  87                 if (!port->on_sysex) {
  88                         consume = i + 1;
  89                         *label = (substream->number << 4) | 0x07;
  90                 /* During exclusive message, use label 0x04. */
  91                 } else if (consume == 3) {
  92                         *label = (substream->number << 4) | 0x04;
  93                 /* We need to fill whole 3 bytes. Go to next change. */
  94                 } else {
  95                         return 0;
  96                 }
  97
  98                 len = consume;
  99         } else {
 100                 /* The beginning of exclusives. */
 101                 if (msg[0] == 0xf0) {
 102                         /* Transfer it in next chance in another condition. */
 103                         port->on_sysex = true;
 104                         return 0;
 105                 } else {
 106                         /* On running-status. */
 107                         if ((msg[0] & 0x80) != 0x80)
 108                                 status = port->running_status;
 109                         else
 110                                 status = msg[0];
 111
 112                         /* Calculate consume bytes. */
 113                         len = calculate_message_bytes(status);
 114                         if (len <= 0)
 115                                 return 0;
 116
 117                         /* On running-status. */
 118                         if ((msg[0] & 0x80) != 0x80) {
 119                                 /* Enough MIDI bytes were not retrieved. */
 120                                 if (consume < len - 1)
 121                                         return 0;
 122                                 consume = len - 1;
 123
 124                                 msg[2] = msg[1];
 125                                 msg[1] = msg[0];
 126                                 msg[0] = port->running_status;
 127                         } else {
 128                                 /* Enough MIDI bytes were not retrieved. */
 129                                 if (consume < len)
 130                                         return 0;
 131                                 consume = len;
 132
 133                                 port->running_status = msg[0];
 134                         }
 135                 }
 136
 137                 *label = (substream->number << 4) | (msg[0] >> 4);
 138         }
 139
 140         if (len > 0 && len < 3)
 141                 memset(msg + len, 0, 3 - len);
 142
 143         return consume;
 144 }
 145
 146 static void async_midi_port_callback(struct fw_card *card, int rcode,
 147                                      void *data, size_t length,
 148                                      void *callback_data)
 149 {
 150         struct snd_fw_async_midi_port *port = callback_data;
 151         struct snd_rawmidi_substream *substream = READ_ONCE(port->substream);
 152
 153         /* This port is closed. */
 154         if (substream == NULL)
 155                 return;
 156
 157         if (rcode == RCODE_COMPLETE)
 158                 snd_rawmidi_transmit_ack(substream, port->consume_bytes);
 159         else if (!rcode_is_permanent_error(rcode))
 160                 /* To start next transaction immediately for recovery. */
 161                 port->next_ktime = 0;
 162         else
 163                 /* Don't continue processing. */
 164                 port->error = true;
 165
 166         port->idling = true;
 167
 168         if (!snd_rawmidi_transmit_empty(substream))
 169                 schedule_work(&port->work);
 170 }
 171
 172 static void midi_port_work(struct work_struct *work)
 173 {
 174         struct snd_fw_async_midi_port *port =
 175                         container_of(work, struct snd_fw_async_midi_port, work);
 176         struct snd_rawmidi_substream *substream = READ_ONCE(port->substream);
 177         int generation;
 178
 179         /* Under transacting or error state. */
 180         if (!port->idling || port->error)
 181                 return;
 182
 183         /* Nothing to do. */
 184         if (substream == NULL || snd_rawmidi_transmit_empty(substream))
 185                 return;
 186
 187         /* Do it in next chance. */
 188         if (ktime_after(port->next_ktime, ktime_get())) {
 189                 schedule_work(&port->work);
 190                 return;
 191         }
 192
 193         /*
 194          * Fill the buffer. The callee must use snd_rawmidi_transmit_peek().
 195          * Later, snd_rawmidi_transmit_ack() is called.
 196          */
 197         memset(port->buf, 0, 4);
 198         port->consume_bytes = fill_message(port, substream);
 199         if (port->consume_bytes <= 0) {
 200                 /* Do it in next chance, immediately. */
 201                 if (port->consume_bytes == 0) {
 202                         port->next_ktime = 0;
 203                         schedule_work(&port->work);
 204                 } else {
 205                         /* Fatal error. */
 206                         port->error = true;
 207                 }
 208                 return;
 209         }
 210
 211         /* Set interval to next transaction. */
 212         port->next_ktime = ktime_add_ns(ktime_get(),
 213                                 port->consume_bytes * 8 * NSEC_PER_SEC / 31250);
 214
 215         /* Start this transaction. */
 216         port->idling = false;
 217
 218         /*
 219          * In Linux FireWire core, when generation is updated with memory
 220          * barrier, node id has already been updated. In this module, After
 221          * this smp_rmb(), load/store instructions to memory are completed.
 222          * Thus, both of generation and node id are available with recent
 223          * values. This is a light-serialization solution to handle bus reset
 224          * events on IEEE 1394 bus.
 225          */
 226         generation = port->parent->generation;
 227         smp_rmb();
 228
 229         fw_send_request(port->parent->card, &port->transaction,
 230                         TCODE_WRITE_QUADLET_REQUEST,
 231                         port->parent->node_id, generation,
 232                         port->parent->max_speed,
 233                         TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_RX_QUAD,
 234                         port->buf, 4, async_midi_port_callback,
 235                         port);
 236 }
 237
 238 void snd_fw_async_midi_port_init(struct snd_fw_async_midi_port *port)
 239 {
 240         port->idling = true;
 241         port->error = false;
 242         port->running_status = 0;
 243         port->on_sysex = false;
 244 }
 245
 246 static void handle_midi_tx(struct fw_card *card, struct fw_request *request,
 247                            int tcode, int destination, int source,
 248                            int generation, unsigned long long offset,
 249                            void *data, size_t length, void *callback_data)
 250 {
 251         struct snd_tscm *tscm = callback_data;
 252         u32 *buf = (u32 *)data;
 253         unsigned int messages;
 254         unsigned int i;
 255         unsigned int port;
 256         struct snd_rawmidi_substream *substream;
 257         u8 *b;
 258         int bytes;
 259
 260         if (offset != tscm->async_handler.offset)
 261                 goto end;
 262
 263         messages = length / 8;
 264         for (i = 0; i < messages; i++) {
 265                 b = (u8 *)(buf + i * 2);
 266
 267                 port = b[0] >> 4;
 268                 /* TODO: support virtual MIDI ports. */
 269                 if (port >= tscm->spec->midi_capture_ports)
 270                         goto end;
 271
 272                 /* Assume the message length. */
 273                 bytes = calculate_message_bytes(b[1]);
 274                 /* On MIDI data or exclusives. */
 275                 if (bytes <= 0) {
 276                         /* Seek the end of exclusives. */
 277                         for (bytes = 1; bytes < 4; bytes++) {
 278                                 if (b[bytes] == 0xf7)
 279                                         break;
 280                         }
 281                         if (bytes == 4)
 282                                 bytes = 3;
 283                 }
 284
 285                 substream = READ_ONCE(tscm->tx_midi_substreams[port]);
 286                 if (substream != NULL)
 287                         snd_rawmidi_receive(substream, b + 1, bytes);
 288         }
 289 end:
 290         fw_send_response(card, request, RCODE_COMPLETE);
 291 }
 292
 293 int snd_tscm_transaction_register(struct snd_tscm *tscm)
 294 {
 295         static const struct fw_address_region resp_register_region = {
 296                 .start  = 0xffffe0000000ull,
 297                 .end    = 0xffffe000ffffull,
 298         };
 299         unsigned int i;
 300         int err;
 301
 302         /*
 303          * Usually, two quadlets are transferred by one transaction. The first
 304          * quadlet has MIDI messages, the rest includes timestamp.
 305          * Sometimes, 8 set of the data is transferred by a block transaction.
 306          */
 307         tscm->async_handler.length = 8 * 8;
 308         tscm->async_handler.address_callback = handle_midi_tx;
 309         tscm->async_handler.callback_data = tscm;
 310
 311         err = fw_core_add_address_handler(&tscm->async_handler,
 312                                           &resp_register_region);
 313         if (err < 0)
 314                 return err;
 315
 316         err = snd_tscm_transaction_reregister(tscm);
 317         if (err < 0)
 318                 goto error;
 319
 320         for (i = 0; i < TSCM_MIDI_OUT_PORT_MAX; i++) {
 321                 tscm->out_ports[i].parent = fw_parent_device(tscm->unit);
 322                 tscm->out_ports[i].next_ktime = 0;
 323                 INIT_WORK(&tscm->out_ports[i].work, midi_port_work);
 324         }
 325
 326         return err;
 327 error:
 328         fw_core_remove_address_handler(&tscm->async_handler);
 329         tscm->async_handler.callback_data = NULL;
 330         return err;
 331 }
 332
 333 /* At bus reset, these registers are cleared. */
 334 int snd_tscm_transaction_reregister(struct snd_tscm *tscm)
 335 {
 336         struct fw_device *device = fw_parent_device(tscm->unit);
 337         __be32 reg;
 338         int err;
 339
 340         /* Register messaging address. Block transaction is not allowed. */
 341         reg = cpu_to_be32((device->card->node_id << 16) |
 342                           (tscm->async_handler.offset >> 32));
 343         err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 344                                  TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ADDR_HI,
 345                                  &reg, sizeof(reg), 0);
 346         if (err < 0)
 347                 return err;
 348
 349         reg = cpu_to_be32(tscm->async_handler.offset);
 350         err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 351                                  TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ADDR_LO,
 352                                  &reg, sizeof(reg), 0);
 353         if (err < 0)
 354                 return err;
 355
 356         /* Turn on messaging. */
 357         reg = cpu_to_be32(0x00000001);
 358         err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 359                                   TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ON,
 360                                   &reg, sizeof(reg), 0);
 361         if (err < 0)
 362                 return err;
 363
 364         /* Turn on FireWire LED. */
 365         reg = cpu_to_be32(0x0001008e);
 366         return snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 367                                   TSCM_ADDR_BASE + TSCM_OFFSET_LED_POWER,
 368                                   &reg, sizeof(reg), 0);
 369 }
 370
 371 void snd_tscm_transaction_unregister(struct snd_tscm *tscm)
 372 {
 373         __be32 reg;
 374
 375         if (tscm->async_handler.callback_data == NULL)
 376                 return;
 377
 378         /* Turn off FireWire LED. */
 379         reg = cpu_to_be32(0x0000008e);
 380         snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 381                            TSCM_ADDR_BASE + TSCM_OFFSET_LED_POWER,
 382                            &reg, sizeof(reg), 0);
 383
 384         /* Turn off messaging. */
 385         reg = cpu_to_be32(0x00000000);
 386         snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 387                            TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ON,
 388                            &reg, sizeof(reg), 0);
 389
 390         /* Unregister the address. */
 391         snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 392                            TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ADDR_HI,
 393                            &reg, sizeof(reg), 0);
 394         snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
 395                            TSCM_ADDR_BASE + TSCM_OFFSET_MIDI_TX_ADDR_LO,
 396                            &reg, sizeof(reg), 0);
 397
 398         fw_core_remove_address_handler(&tscm->async_handler);
 399         tscm->async_handler.callback_data = NULL;
 400 }