sound/oss/uart401.c

   1 /*
   2  * sound/uart401.c
   3  *
   4  * MPU-401 UART driver (formerly uart401_midi.c)
   5  *
   6  *
   7  * Copyright (C) by Hannu Savolainen 1993-1997
   8  *
   9  * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
  10  * Version 2 (June 1991). See the "COPYING" file distributed with this software
  11  * for more info.
  12  *
  13  * Changes:
  14  *      Alan Cox                Reformatted, removed sound_mem usage, use normal Linux
  15  *                              interrupt allocation. Protect against bogus unload
  16  *                              Fixed to allow IRQ > 15
  17  *      Christoph Hellwig       Adapted to module_init/module_exit
  18  *      Arnaldo C. de Melo      got rid of check_region
  19  *
  20  * Status:
  21  *              Untested
  22  */
  23
  24 #include <linux/init.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/module.h>
  27 #include <linux/spinlock.h>
  28 #include "sound_config.h"
  29
  30 #include "mpu401.h"
  31
  32 typedef struct uart401_devc
  33 {
  34         int             base;
  35         int             irq;
  36         int            *osp;
  37         void            (*midi_input_intr) (int dev, unsigned char data);
  38         int             opened, disabled;
  39         volatile unsigned char input_byte;
  40         int             my_dev;
  41         int             share_irq;
  42         spinlock_t      lock;
  43 }
  44 uart401_devc;
  45
  46 #define DATAPORT   (devc->base)
  47 #define COMDPORT   (devc->base+1)
  48 #define STATPORT   (devc->base+1)
  49
  50 static int uart401_status(uart401_devc * devc)
  51 {
  52         return inb(STATPORT);
  53 }
  54
  55 #define input_avail(devc) (!(uart401_status(devc)&INPUT_AVAIL))
  56 #define output_ready(devc)      (!(uart401_status(devc)&OUTPUT_READY))
  57
  58 static void uart401_cmd(uart401_devc * devc, unsigned char cmd)
  59 {
  60         outb((cmd), COMDPORT);
  61 }
  62
  63 static int uart401_read(uart401_devc * devc)
  64 {
  65         return inb(DATAPORT);
  66 }
  67
  68 static void uart401_write(uart401_devc * devc, unsigned char byte)
  69 {
  70         outb((byte), DATAPORT);
  71 }
  72
  73 #define OUTPUT_READY    0x40
  74 #define INPUT_AVAIL     0x80
  75 #define MPU_ACK         0xFE
  76 #define MPU_RESET       0xFF
  77 #define UART_MODE_ON    0x3F
  78
  79 static int      reset_uart401(uart401_devc * devc);
  80 static void     enter_uart_mode(uart401_devc * devc);
  81
  82 static void uart401_input_loop(uart401_devc * devc)
  83 {
  84         int work_limit=30000;
  85
  86         while (input_avail(devc) && --work_limit)
  87         {
  88                 unsigned char   c = uart401_read(devc);
  89
  90                 if (c == MPU_ACK)
  91                         devc->input_byte = c;
  92                 else if (devc->opened & OPEN_READ && devc->midi_input_intr)
  93                         devc->midi_input_intr(devc->my_dev, c);
  94         }
  95         if(work_limit==0)
  96                 printk(KERN_WARNING "Too much work in interrupt on uart401 (0x%X). UART jabbering ??\n", devc->base);
  97 }
  98
  99 void uart401intr(int irq, void *dev_id, struct pt_regs *dummy)
 100 {
 101         uart401_devc *devc = dev_id;
 102
 103         if (devc == NULL)
 104         {
 105                 printk(KERN_ERR "uart401: bad devc\n");
 106                 return;
 107         }
 108
 109         if (input_avail(devc))
 110                 uart401_input_loop(devc);
 111 }
 112
 113 static int
 114 uart401_open(int dev, int mode,
 115              void            (*input) (int dev, unsigned char data),
 116              void            (*output) (int dev)
 117 )
 118 {
 119         uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
 120
 121         if (devc->opened)
 122                 return -EBUSY;
 123
 124         /* Flush the UART */
 125
 126         while (input_avail(devc))
 127                 uart401_read(devc);
 128
 129         devc->midi_input_intr = input;
 130         devc->opened = mode;
 131         enter_uart_mode(devc);
 132         devc->disabled = 0;
 133
 134         return 0;
 135 }
 136
 137 static void uart401_close(int dev)
 138 {
 139         uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
 140
 141         reset_uart401(devc);
 142         devc->opened = 0;
 143 }
 144
 145 static int uart401_out(int dev, unsigned char midi_byte)
 146 {
 147         int timeout;
 148         unsigned long flags;
 149         uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
 150
 151         if (devc->disabled)
 152                 return 1;
 153         /*
 154          * Test for input since pending input seems to block the output.
 155          */
 156
 157         spin_lock_irqsave(&devc->lock,flags);
 158         if (input_avail(devc))
 159                 uart401_input_loop(devc);
 160
 161         spin_unlock_irqrestore(&devc->lock,flags);
 162
 163         /*
 164          * Sometimes it takes about 13000 loops before the output becomes ready
 165          * (After reset). Normally it takes just about 10 loops.
 166          */
 167
 168         for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
 169
 170         if (!output_ready(devc))
 171         {
 172                   printk(KERN_WARNING "uart401: Timeout - Device not responding\n");
 173                   devc->disabled = 1;
 174                   reset_uart401(devc);
 175                   enter_uart_mode(devc);
 176                   return 1;
 177         }
 178         uart401_write(devc, midi_byte);
 179         return 1;
 180 }
 181
 182 static inline int uart401_start_read(int dev)
 183 {
 184         return 0;
 185 }
 186
 187 static inline int uart401_end_read(int dev)
 188 {
 189         return 0;
 190 }
 191
 192 static inline void uart401_kick(int dev)
 193 {
 194 }
 195
 196 static inline int uart401_buffer_status(int dev)
 197 {
 198         return 0;
 199 }
 200
 201 #define MIDI_SYNTH_NAME "MPU-401 UART"
 202 #define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT
 203 #include "midi_synth.h"
 204
 205 static const struct midi_operations uart401_operations =
 206 {
 207         owner:          THIS_MODULE,
 208         info:           {"MPU-401 (UART) MIDI", 0, 0, SNDCARD_MPU401},
 209         converter:      &std_midi_synth,
 210         in_info:        {0},
 211         open:           uart401_open,
 212         close:          uart401_close,
 213         outputc:        uart401_out,
 214         start_read:     uart401_start_read,
 215         end_read:       uart401_end_read,
 216         kick:           uart401_kick,
 217         buffer_status:  uart401_buffer_status,
 218 };
 219
 220 static void enter_uart_mode(uart401_devc * devc)
 221 {
 222         int ok, timeout;
 223         unsigned long flags;
 224
 225         spin_lock_irqsave(&devc->lock,flags);
 226         for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
 227
 228         devc->input_byte = 0;
 229         uart401_cmd(devc, UART_MODE_ON);
 230
 231         ok = 0;
 232         for (timeout = 50000; timeout > 0 && !ok; timeout--)
 233                 if (devc->input_byte == MPU_ACK)
 234                         ok = 1;
 235                 else if (input_avail(devc))
 236                         if (uart401_read(devc) == MPU_ACK)
 237                                 ok = 1;
 238
 239         spin_unlock_irqrestore(&devc->lock,flags);
 240 }
 241
 242 static int reset_uart401(uart401_devc * devc)
 243 {
 244         int ok, timeout, n;
 245
 246         /*
 247          * Send the RESET command. Try again if no success at the first time.
 248          */
 249
 250         ok = 0;
 251
 252         for (n = 0; n < 2 && !ok; n++)
 253         {
 254                 for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
 255                 devc->input_byte = 0;
 256                 uart401_cmd(devc, MPU_RESET);
 257
 258                 /*
 259                  * Wait at least 25 msec. This method is not accurate so let's make the
 260                  * loop bit longer. Cannot sleep since this is called during boot.
 261                  */
 262
 263                 for (timeout = 50000; timeout > 0 && !ok; timeout--)
 264                 {
 265                         if (devc->input_byte == MPU_ACK)        /* Interrupt */
 266                                 ok = 1;
 267                         else if (input_avail(devc))
 268                         {
 269                                 if (uart401_read(devc) == MPU_ACK)
 270                                         ok = 1;
 271                         }
 272                 }
 273         }
 274
 275
 276         if (ok)
 277         {
 278                 DEB(printk("Reset UART401 OK\n"));
 279         }
 280         else
 281                 DDB(printk("Reset UART401 failed - No hardware detected.\n"));
 282
 283         if (ok)
 284                 uart401_input_loop(devc);       /*
 285                                                  * Flush input before enabling interrupts
 286                                                  */
 287
 288         return ok;
 289 }
 290
 291 int probe_uart401(struct address_info *hw_config, struct module *owner)
 292 {
 293         uart401_devc *devc;
 294         char *name = "MPU-401 (UART) MIDI";
 295         int ok = 0;
 296         unsigned long flags;
 297
 298         DDB(printk("Entered probe_uart401()\n"));
 299
 300         /* Default to "not found" */
 301         hw_config->slots[4] = -1;
 302
 303         if (!request_region(hw_config->io_base, 4, "MPU-401 UART")) {
 304                 printk(KERN_INFO "uart401: could not request_region(%d, 4)\n", hw_config->io_base);
 305                 return 0;
 306         }
 307
 308         devc = kmalloc(sizeof(uart401_devc), GFP_KERNEL);
 309         if (!devc) {
 310                 printk(KERN_WARNING "uart401: Can't allocate memory\n");
 311                 goto cleanup_region;
 312         }
 313
 314         devc->base = hw_config->io_base;
 315         devc->irq = hw_config->irq;
 316         devc->osp = hw_config->osp;
 317         devc->midi_input_intr = NULL;
 318         devc->opened = 0;
 319         devc->input_byte = 0;
 320         devc->my_dev = 0;
 321         devc->share_irq = 0;
 322         spin_lock_init(&devc->lock);
 323
 324         spin_lock_irqsave(&devc->lock,flags);
 325         ok = reset_uart401(devc);
 326         spin_unlock_irqrestore(&devc->lock,flags);
 327
 328         if (!ok)
 329                 goto cleanup_devc;
 330
 331         if (hw_config->name)
 332                 name = hw_config->name;
 333
 334         if (devc->irq < 0) {
 335                 devc->share_irq = 1;
 336                 devc->irq *= -1;
 337         } else
 338                 devc->share_irq = 0;
 339
 340         if (!devc->share_irq)
 341                 if (request_irq(devc->irq, uart401intr, 0, "MPU-401 UART", devc) < 0) {
 342                         printk(KERN_WARNING "uart401: Failed to allocate IRQ%d\n", devc->irq);
 343                         devc->share_irq = 1;
 344                 }
 345         devc->my_dev = sound_alloc_mididev();
 346         enter_uart_mode(devc);
 347
 348         if (devc->my_dev == -1) {
 349                 printk(KERN_INFO "uart401: Too many midi devices detected\n");
 350                 goto cleanup_irq;
 351         }
 352         conf_printf(name, hw_config);
 353         midi_devs[devc->my_dev] = kmalloc(sizeof(struct midi_operations), GFP_KERNEL);
 354         if (!midi_devs[devc->my_dev]) {
 355                 printk(KERN_ERR "uart401: Failed to allocate memory\n");
 356                 goto cleanup_unload_mididev;
 357         }
 358         memcpy(midi_devs[devc->my_dev], &uart401_operations, sizeof(struct midi_operations));
 359
 360         if (owner)
 361                 midi_devs[devc->my_dev]->owner = owner;
 362
 363         midi_devs[devc->my_dev]->devc = devc;
 364         midi_devs[devc->my_dev]->converter = kmalloc(sizeof(struct synth_operations), GFP_KERNEL);
 365         if (!midi_devs[devc->my_dev]->converter) {
 366                 printk(KERN_WARNING "uart401: Failed to allocate memory\n");
 367                 goto cleanup_midi_devs;
 368         }
 369         memcpy(midi_devs[devc->my_dev]->converter, &std_midi_synth, sizeof(struct synth_operations));
 370         strcpy(midi_devs[devc->my_dev]->info.name, name);
 371         midi_devs[devc->my_dev]->converter->id = "UART401";
 372         midi_devs[devc->my_dev]->converter->midi_dev = devc->my_dev;
 373
 374         if (owner)
 375                 midi_devs[devc->my_dev]->converter->owner = owner;
 376
 377         hw_config->slots[4] = devc->my_dev;
 378         sequencer_init();
 379         devc->opened = 0;
 380         return 1;
 381 cleanup_midi_devs:
 382         kfree(midi_devs[devc->my_dev]);
 383 cleanup_unload_mididev:
 384         sound_unload_mididev(devc->my_dev);
 385 cleanup_irq:
 386         if (!devc->share_irq)
 387                 free_irq(devc->irq, devc);
 388 cleanup_devc:
 389         kfree(devc);
 390 cleanup_region:
 391         release_region(hw_config->io_base, 4);
 392         return 0;
 393 }
 394
 395 void unload_uart401(struct address_info *hw_config)
 396 {
 397         uart401_devc *devc;
 398         int n=hw_config->slots[4];
 399
 400         /* Not set up */
 401         if(n==-1 || midi_devs[n]==NULL)
 402                 return;
 403
 404         /* Not allocated (erm ??) */
 405
 406         devc = midi_devs[hw_config->slots[4]]->devc;
 407         if (devc == NULL)
 408                 return;
 409
 410         reset_uart401(devc);
 411         release_region(hw_config->io_base, 4);
 412
 413         if (!devc->share_irq)
 414                 free_irq(devc->irq, devc);
 415         if (devc)
 416         {
 417                 kfree(midi_devs[devc->my_dev]->converter);
 418                 kfree(midi_devs[devc->my_dev]);
 419                 kfree(devc);
 420                 devc = NULL;
 421         }
 422         /* This kills midi_devs[x] */
 423         sound_unload_mididev(hw_config->slots[4]);
 424 }
 425
 426 EXPORT_SYMBOL(probe_uart401);
 427 EXPORT_SYMBOL(unload_uart401);
 428 EXPORT_SYMBOL(uart401intr);
 429
 430 static struct address_info cfg_mpu;
 431
 432 static int __initdata io = -1;
 433 static int __initdata irq = -1;
 434
 435 MODULE_PARM(io, "i");
 436 MODULE_PARM(irq, "i");
 437
 438
 439 static int __init init_uart401(void)
 440 {
 441         cfg_mpu.irq = irq;
 442         cfg_mpu.io_base = io;
 443
 444         /* Can be loaded either for module use or to provide functions
 445            to others */
 446         if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1) {
 447                 printk(KERN_INFO "MPU-401 UART driver Copyright (C) Hannu Savolainen 1993-1997");
 448                 if (!probe_uart401(&cfg_mpu, THIS_MODULE))
 449                         return -ENODEV;
 450         }
 451
 452         return 0;
 453 }
 454
 455 static void __exit cleanup_uart401(void)
 456 {
 457         if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1)
 458                 unload_uart401(&cfg_mpu);
 459 }
 460
 461 module_init(init_uart401);
 462 module_exit(cleanup_uart401);
 463
 464 #ifndef MODULE
 465 static int __init setup_uart401(char *str)
 466 {
 467         /* io, irq */
 468         int ints[3];
 469
 470         str = get_options(str, ARRAY_SIZE(ints), ints);
 471
 472         io = ints[1];
 473         irq = ints[2];
 474
 475         return 1;
 476 }
 477
 478 __setup("uart401=", setup_uart401);
 479 #endif
 480 MODULE_LICENSE("GPL");