sound/drivers/mpu401/mpu401_uart.c

   1 /*
   2  *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
   3  *  Routines for control of MPU-401 in UART mode
   4  *
   5  *  MPU-401 supports UART mode which is not capable generate transmit
   6  *  interrupts thus output is done via polling. Also, if irq < 0, then
   7  *  input is done also via polling. Do not expect good performance.
   8  *
   9  *
  10  *   This program is free software; you can redistribute it and/or modify
  11  *   it under the terms of the GNU General Public License as published by
  12  *   the Free Software Foundation; either version 2 of the License, or
  13  *   (at your option) any later version.
  14  *
  15  *   This program is distributed in the hope that it will be useful,
  16  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  *   GNU General Public License for more details.
  19  *
  20  *   You should have received a copy of the GNU General Public License
  21  *   along with this program; if not, write to the Free Software
  22  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  23  *
  24  *   13-03-2003:
  25  *      Added support for different kind of hardware I/O. Build in choices
  26  *      are port and mmio. For other kind of I/O, set mpu->read and
  27  *      mpu->write to your own I/O functions.
  28  *
  29  */
  30
  31 #include <sound/driver.h>
  32 #include <asm/io.h>
  33 #include <linux/delay.h>
  34 #include <linux/init.h>
  35 #include <linux/slab.h>
  36 #include <linux/ioport.h>
  37 #include <linux/interrupt.h>
  38 #include <linux/errno.h>
  39 #include <sound/core.h>
  40 #include <sound/mpu401.h>
  41
  42 MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
  43 MODULE_DESCRIPTION("Routines for control of MPU-401 in UART mode");
  44 MODULE_LICENSE("GPL");
  45
  46 static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu);
  47 static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu);
  48
  49 /*
  50
  51  */
  52
  53 #define snd_mpu401_input_avail(mpu)     (!(mpu->read(mpu, MPU401C(mpu)) & 0x80))
  54 #define snd_mpu401_output_ready(mpu)    (!(mpu->read(mpu, MPU401C(mpu)) & 0x40))
  55
  56 #define MPU401_RESET            0xff
  57 #define MPU401_ENTER_UART       0x3f
  58 #define MPU401_ACK              0xfe
  59
  60 /* Build in lowlevel io */
  61 static void mpu401_write_port(struct snd_mpu401 *mpu, unsigned char data, unsigned long addr)
  62 {
  63         outb(data, addr);
  64 }
  65
  66 static unsigned char mpu401_read_port(struct snd_mpu401 *mpu, unsigned long addr)
  67 {
  68         return inb(addr);
  69 }
  70
  71 static void mpu401_write_mmio(struct snd_mpu401 *mpu, unsigned char data, unsigned long addr)
  72 {
  73         writeb(data, (void __iomem *)addr);
  74 }
  75
  76 static unsigned char mpu401_read_mmio(struct snd_mpu401 *mpu, unsigned long addr)
  77 {
  78         return readb((void __iomem *)addr);
  79 }
  80 /*  */
  81
  82 static void snd_mpu401_uart_clear_rx(struct snd_mpu401 *mpu)
  83 {
  84         int timeout = 100000;
  85         for (; timeout > 0 && snd_mpu401_input_avail(mpu); timeout--)
  86                 mpu->read(mpu, MPU401D(mpu));
  87 #ifdef CONFIG_SND_DEBUG
  88         if (timeout <= 0)
  89                 snd_printk("cmd: clear rx timeout (status = 0x%x)\n", mpu->read(mpu, MPU401C(mpu)));
  90 #endif
  91 }
  92
  93 static void _snd_mpu401_uart_interrupt(struct snd_mpu401 *mpu)
  94 {
  95         spin_lock(&mpu->input_lock);
  96         if (test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode)) {
  97                 snd_mpu401_uart_input_read(mpu);
  98         } else {
  99                 snd_mpu401_uart_clear_rx(mpu);
 100         }
 101         spin_unlock(&mpu->input_lock);
 102         /* ok. for better Tx performance try do some output when input is done */
 103         if (test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode) &&
 104             test_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode)) {
 105                 spin_lock(&mpu->output_lock);
 106                 snd_mpu401_uart_output_write(mpu);
 107                 spin_unlock(&mpu->output_lock);
 108         }
 109 }
 110
 111 /**
 112  * snd_mpu401_uart_interrupt - generic MPU401-UART interrupt handler
 113  * @irq: the irq number
 114  * @dev_id: mpu401 instance
 115  * @regs: the reigster
 116  *
 117  * Processes the interrupt for MPU401-UART i/o.
 118  */
 119 irqreturn_t snd_mpu401_uart_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 120 {
 121         struct snd_mpu401 *mpu = dev_id;
 122
 123         if (mpu == NULL)
 124                 return IRQ_NONE;
 125         _snd_mpu401_uart_interrupt(mpu);
 126         return IRQ_HANDLED;
 127 }
 128
 129 /*
 130  * timer callback
 131  * reprogram the timer and call the interrupt job
 132  */
 133 static void snd_mpu401_uart_timer(unsigned long data)
 134 {
 135         struct snd_mpu401 *mpu = (struct snd_mpu401 *)data;
 136         unsigned long flags;
 137
 138         spin_lock_irqsave(&mpu->timer_lock, flags);
 139         /*mpu->mode |= MPU401_MODE_TIMER;*/
 140         mpu->timer.expires = 1 + jiffies;
 141         add_timer(&mpu->timer);
 142         spin_unlock_irqrestore(&mpu->timer_lock, flags);
 143         if (mpu->rmidi)
 144                 _snd_mpu401_uart_interrupt(mpu);
 145 }
 146
 147 /*
 148  * initialize the timer callback if not programmed yet
 149  */
 150 static void snd_mpu401_uart_add_timer (struct snd_mpu401 *mpu, int input)
 151 {
 152         unsigned long flags;
 153
 154         spin_lock_irqsave (&mpu->timer_lock, flags);
 155         if (mpu->timer_invoked == 0) {
 156                 init_timer(&mpu->timer);
 157                 mpu->timer.data = (unsigned long)mpu;
 158                 mpu->timer.function = snd_mpu401_uart_timer;
 159                 mpu->timer.expires = 1 + jiffies;
 160                 add_timer(&mpu->timer);
 161         }
 162         mpu->timer_invoked |= input ? MPU401_MODE_INPUT_TIMER : MPU401_MODE_OUTPUT_TIMER;
 163         spin_unlock_irqrestore (&mpu->timer_lock, flags);
 164 }
 165
 166 /*
 167  * remove the timer callback if still active
 168  */
 169 static void snd_mpu401_uart_remove_timer (struct snd_mpu401 *mpu, int input)
 170 {
 171         unsigned long flags;
 172
 173         spin_lock_irqsave (&mpu->timer_lock, flags);
 174         if (mpu->timer_invoked) {
 175                 mpu->timer_invoked &= input ? ~MPU401_MODE_INPUT_TIMER : ~MPU401_MODE_OUTPUT_TIMER;
 176                 if (! mpu->timer_invoked)
 177                         del_timer(&mpu->timer);
 178         }
 179         spin_unlock_irqrestore (&mpu->timer_lock, flags);
 180 }
 181
 182 /*
 183
 184  */
 185
 186 static void snd_mpu401_uart_cmd(struct snd_mpu401 * mpu, unsigned char cmd, int ack)
 187 {
 188         unsigned long flags;
 189         int timeout, ok;
 190
 191         spin_lock_irqsave(&mpu->input_lock, flags);
 192         if (mpu->hardware != MPU401_HW_TRID4DWAVE) {
 193                 mpu->write(mpu, 0x00, MPU401D(mpu));
 194                 /*snd_mpu401_uart_clear_rx(mpu);*/
 195         }
 196         /* ok. standard MPU-401 initialization */
 197         if (mpu->hardware != MPU401_HW_SB) {
 198                 for (timeout = 1000; timeout > 0 && !snd_mpu401_output_ready(mpu); timeout--)
 199                         udelay(10);
 200 #ifdef CONFIG_SND_DEBUG
 201                 if (!timeout)
 202                         snd_printk("cmd: tx timeout (status = 0x%x)\n", mpu->read(mpu, MPU401C(mpu)));
 203 #endif
 204         }
 205         mpu->write(mpu, cmd, MPU401C(mpu));
 206         if (ack) {
 207                 ok = 0;
 208                 timeout = 10000;
 209                 while (!ok && timeout-- > 0) {
 210                         if (snd_mpu401_input_avail(mpu)) {
 211                                 if (mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
 212                                         ok = 1;
 213                         }
 214                 }
 215                 if (!ok && mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
 216                         ok = 1;
 217         } else {
 218                 ok = 1;
 219         }
 220         spin_unlock_irqrestore(&mpu->input_lock, flags);
 221         if (! ok)
 222                 snd_printk("cmd: 0x%x failed at 0x%lx (status = 0x%x, data = 0x%x)\n", cmd, mpu->port, mpu->read(mpu, MPU401C(mpu)), mpu->read(mpu, MPU401D(mpu)));
 223         // snd_printk("cmd: 0x%x at 0x%lx (status = 0x%x, data = 0x%x)\n", cmd, mpu->port, mpu->read(mpu, MPU401C(mpu)), mpu->read(mpu, MPU401D(mpu)));
 224 }
 225
 226 /*
 227  * input/output open/close - protected by open_mutex in rawmidi.c
 228  */
 229 static int snd_mpu401_uart_input_open(struct snd_rawmidi_substream *substream)
 230 {
 231         struct snd_mpu401 *mpu;
 232         int err;
 233
 234         mpu = substream->rmidi->private_data;
 235         if (mpu->open_input && (err = mpu->open_input(mpu)) < 0)
 236                 return err;
 237         if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode)) {
 238                 snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1);
 239                 snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 1);
 240         }
 241         mpu->substream_input = substream;
 242         set_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
 243         return 0;
 244 }
 245
 246 static int snd_mpu401_uart_output_open(struct snd_rawmidi_substream *substream)
 247 {
 248         struct snd_mpu401 *mpu;
 249         int err;
 250
 251         mpu = substream->rmidi->private_data;
 252         if (mpu->open_output && (err = mpu->open_output(mpu)) < 0)
 253                 return err;
 254         if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode)) {
 255                 snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1);
 256                 snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 1);
 257         }
 258         mpu->substream_output = substream;
 259         set_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
 260         return 0;
 261 }
 262
 263 static int snd_mpu401_uart_input_close(struct snd_rawmidi_substream *substream)
 264 {
 265         struct snd_mpu401 *mpu;
 266
 267         mpu = substream->rmidi->private_data;
 268         clear_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
 269         mpu->substream_input = NULL;
 270         if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode))
 271                 snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
 272         if (mpu->close_input)
 273                 mpu->close_input(mpu);
 274         return 0;
 275 }
 276
 277 static int snd_mpu401_uart_output_close(struct snd_rawmidi_substream *substream)
 278 {
 279         struct snd_mpu401 *mpu;
 280
 281         mpu = substream->rmidi->private_data;
 282         clear_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
 283         mpu->substream_output = NULL;
 284         if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode))
 285                 snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
 286         if (mpu->close_output)
 287                 mpu->close_output(mpu);
 288         return 0;
 289 }
 290
 291 /*
 292  * trigger input callback
 293  */
 294 static void snd_mpu401_uart_input_trigger(struct snd_rawmidi_substream *substream, int up)
 295 {
 296         unsigned long flags;
 297         struct snd_mpu401 *mpu;
 298         int max = 64;
 299
 300         mpu = substream->rmidi->private_data;
 301         if (up) {
 302                 if (! test_and_set_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode)) {
 303                         /* first time - flush FIFO */
 304                         while (max-- > 0)
 305                                 mpu->read(mpu, MPU401D(mpu));
 306                         if (mpu->irq < 0)
 307                                 snd_mpu401_uart_add_timer(mpu, 1);
 308                 }
 309
 310                 /* read data in advance */
 311                 spin_lock_irqsave(&mpu->input_lock, flags);
 312                 snd_mpu401_uart_input_read(mpu);
 313                 spin_unlock_irqrestore(&mpu->input_lock, flags);
 314         } else {
 315                 if (mpu->irq < 0)
 316                         snd_mpu401_uart_remove_timer(mpu, 1);
 317                 clear_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode);
 318         }
 319 }
 320
 321 /*
 322  * transfer input pending data
 323  * call with input_lock spinlock held
 324  */
 325 static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu)
 326 {
 327         int max = 128;
 328         unsigned char byte;
 329
 330         while (max-- > 0) {
 331                 if (snd_mpu401_input_avail(mpu)) {
 332                         byte = mpu->read(mpu, MPU401D(mpu));
 333                         if (test_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode))
 334                                 snd_rawmidi_receive(mpu->substream_input, &byte, 1);
 335                 } else {
 336                         break; /* input not available */
 337                 }
 338         }
 339 }
 340
 341 /*
 342  *  Tx FIFO sizes:
 343  *    CS4237B                   - 16 bytes
 344  *    AudioDrive ES1688         - 12 bytes
 345  *    S3 SonicVibes             -  8 bytes
 346  *    SoundBlaster AWE 64       -  2 bytes (ugly hardware)
 347  */
 348
 349 /*
 350  * write output pending bytes
 351  * call with output_lock spinlock held
 352  */
 353 static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu)
 354 {
 355         unsigned char byte;
 356         int max = 256, timeout;
 357
 358         do {
 359                 if (snd_rawmidi_transmit_peek(mpu->substream_output, &byte, 1) == 1) {
 360                         for (timeout = 100; timeout > 0; timeout--) {
 361                                 if (snd_mpu401_output_ready(mpu)) {
 362                                         mpu->write(mpu, byte, MPU401D(mpu));
 363                                         snd_rawmidi_transmit_ack(mpu->substream_output, 1);
 364                                         break;
 365                                 }
 366                         }
 367                         if (timeout == 0)
 368                                 break;  /* Tx FIFO full - try again later */
 369                 } else {
 370                         snd_mpu401_uart_remove_timer (mpu, 0);
 371                         break;  /* no other data - leave the tx loop */
 372                 }
 373         } while (--max > 0);
 374 }
 375
 376 /*
 377  * output trigger callback
 378  */
 379 static void snd_mpu401_uart_output_trigger(struct snd_rawmidi_substream *substream, int up)
 380 {
 381         unsigned long flags;
 382         struct snd_mpu401 *mpu;
 383
 384         mpu = substream->rmidi->private_data;
 385         if (up) {
 386                 set_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);
 387
 388                 /* try to add the timer at each output trigger,
 389                  * since the output timer might have been removed in
 390                  * snd_mpu401_uart_output_write().
 391                  */
 392                 snd_mpu401_uart_add_timer(mpu, 0);
 393
 394                 /* output pending data */
 395                 spin_lock_irqsave(&mpu->output_lock, flags);
 396                 snd_mpu401_uart_output_write(mpu);
 397                 spin_unlock_irqrestore(&mpu->output_lock, flags);
 398         } else {
 399                 snd_mpu401_uart_remove_timer(mpu, 0);
 400                 clear_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);
 401         }
 402 }
 403
 404 /*
 405
 406  */
 407
 408 static struct snd_rawmidi_ops snd_mpu401_uart_output =
 409 {
 410         .open =         snd_mpu401_uart_output_open,
 411         .close =        snd_mpu401_uart_output_close,
 412         .trigger =      snd_mpu401_uart_output_trigger,
 413 };
 414
 415 static struct snd_rawmidi_ops snd_mpu401_uart_input =
 416 {
 417         .open =         snd_mpu401_uart_input_open,
 418         .close =        snd_mpu401_uart_input_close,
 419         .trigger =      snd_mpu401_uart_input_trigger,
 420 };
 421
 422 static void snd_mpu401_uart_free(struct snd_rawmidi *rmidi)
 423 {
 424         struct snd_mpu401 *mpu = rmidi->private_data;
 425         if (mpu->irq_flags && mpu->irq >= 0)
 426                 free_irq(mpu->irq, (void *) mpu);
 427         release_and_free_resource(mpu->res);
 428         kfree(mpu);
 429 }
 430
 431 /**
 432  * snd_mpu401_uart_new - create an MPU401-UART instance
 433  * @card: the card instance
 434  * @device: the device index, zero-based
 435  * @hardware: the hardware type, MPU401_HW_XXXX
 436  * @port: the base address of MPU401 port
 437  * @integrated: non-zero if the port was already reserved by the chip
 438  * @irq: the irq number, -1 if no interrupt for mpu
 439  * @irq_flags: the irq request flags (SA_XXX), 0 if irq was already reserved.
 440  * @rrawmidi: the pointer to store the new rawmidi instance
 441  *
 442  * Creates a new MPU-401 instance.
 443  *
 444  * Note that the rawmidi instance is returned on the rrawmidi argument,
 445  * not the mpu401 instance itself.  To access to the mpu401 instance,
 446  * cast from rawmidi->private_data (with struct snd_mpu401 magic-cast).
 447  *
 448  * Returns zero if successful, or a negative error code.
 449  */
 450 int snd_mpu401_uart_new(struct snd_card *card, int device,
 451                         unsigned short hardware,
 452                         unsigned long port, int integrated,
 453                         int irq, int irq_flags,
 454                         struct snd_rawmidi ** rrawmidi)
 455 {
 456         struct snd_mpu401 *mpu;
 457         struct snd_rawmidi *rmidi;
 458         int err;
 459
 460         if (rrawmidi)
 461                 *rrawmidi = NULL;
 462         if ((err = snd_rawmidi_new(card, "MPU-401U", device, 1, 1, &rmidi)) < 0)
 463                 return err;
 464         mpu = kzalloc(sizeof(*mpu), GFP_KERNEL);
 465         if (mpu == NULL) {
 466                 snd_printk(KERN_ERR "mpu401_uart: cannot allocate\n");
 467                 snd_device_free(card, rmidi);
 468                 return -ENOMEM;
 469         }
 470         rmidi->private_data = mpu;
 471         rmidi->private_free = snd_mpu401_uart_free;
 472         spin_lock_init(&mpu->input_lock);
 473         spin_lock_init(&mpu->output_lock);
 474         spin_lock_init(&mpu->timer_lock);
 475         mpu->hardware = hardware;
 476         if (!integrated) {
 477                 int res_size = hardware == MPU401_HW_PC98II ? 4 : 2;
 478                 if ((mpu->res = request_region(port, res_size, "MPU401 UART")) == NULL) {
 479                         snd_printk(KERN_ERR "mpu401_uart: unable to grab port 0x%lx size %d\n", port, res_size);
 480                         snd_device_free(card, rmidi);
 481                         return -EBUSY;
 482                 }
 483         }
 484         switch (hardware) {
 485         case MPU401_HW_AUREAL:
 486                 mpu->write = mpu401_write_mmio;
 487                 mpu->read = mpu401_read_mmio;
 488                 break;
 489         default:
 490                 mpu->write = mpu401_write_port;
 491                 mpu->read = mpu401_read_port;
 492                 break;
 493         }
 494         mpu->port = port;
 495         if (hardware == MPU401_HW_PC98II)
 496                 mpu->cport = port + 2;
 497         else
 498                 mpu->cport = port + 1;
 499         if (irq >= 0 && irq_flags) {
 500                 if (request_irq(irq, snd_mpu401_uart_interrupt, irq_flags, "MPU401 UART", (void *) mpu)) {
 501                         snd_printk(KERN_ERR "mpu401_uart: unable to grab IRQ %d\n", irq);
 502                         snd_device_free(card, rmidi);
 503                         return -EBUSY;
 504                 }
 505         }
 506         mpu->irq = irq;
 507         mpu->irq_flags = irq_flags;
 508         if (card->shortname[0])
 509                 snprintf(rmidi->name, sizeof(rmidi->name), "%s MIDI", card->shortname);
 510         else
 511                 sprintf(rmidi->name, "MPU-401 MIDI %d-%d", card->number, device);
 512         snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_mpu401_uart_output);
 513         snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_mpu401_uart_input);
 514         rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT |
 515                              SNDRV_RAWMIDI_INFO_INPUT |
 516                              SNDRV_RAWMIDI_INFO_DUPLEX;
 517         mpu->rmidi = rmidi;
 518         if (rrawmidi)
 519                 *rrawmidi = rmidi;
 520         return 0;
 521 }
 522
 523 EXPORT_SYMBOL(snd_mpu401_uart_interrupt);
 524 EXPORT_SYMBOL(snd_mpu401_uart_new);
 525
 526 /*
 527  *  INIT part
 528  */
 529
 530 static int __init alsa_mpu401_uart_init(void)
 531 {
 532         return 0;
 533 }
 534
 535 static void __exit alsa_mpu401_uart_exit(void)
 536 {
 537 }
 538
 539 module_init(alsa_mpu401_uart_init)
 540 module_exit(alsa_mpu401_uart_exit)