sound/oss/uart6850.c

   1 /*
   2  * sound/uart6850.c
   3  *
   4  *
   5  * Copyright (C) by Hannu Savolainen 1993-1997
   6  *
   7  * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
   8  * Version 2 (June 1991). See the "COPYING" file distributed with this software
   9  * for more info.
  10  * Extended by Alan Cox for Red Hat Software. Now a loadable MIDI driver.
  11  * 28/4/97 - (C) Copyright Alan Cox. Released under the GPL version 2.
  12  *
  13  * Alan Cox:            Updated for new modular code. Removed snd_* irq handling. Now
  14  *                      uses native linux resources
  15  * Christoph Hellwig:   Adapted to module_init/module_exit
  16  * Jeff Garzik:         Made it work again, in theory
  17  *                      FIXME: If the request_irq() succeeds, the probe succeeds. Ug.
  18  *
  19  *      Status: Testing required (no shit -jgarzik)
  20  *
  21  *
  22  */
  23
  24 #include <linux/init.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/module.h>
  27 #include <linux/spinlock.h>
  28 /* Mon Nov 22 22:38:35 MET 1993 marco@driq.home.usn.nl:
  29  *      added 6850 support, used with COVOX SoundMaster II and custom cards.
  30  */
  31
  32 #include "sound_config.h"
  33
  34 static int uart6850_base = 0x330;
  35
  36 static int *uart6850_osp;
  37
  38 #define DATAPORT   (uart6850_base)
  39 #define COMDPORT   (uart6850_base+1)
  40 #define STATPORT   (uart6850_base+1)
  41
  42 static int uart6850_status(void)
  43 {
  44         return inb(STATPORT);
  45 }
  46
  47 #define input_avail()           (uart6850_status()&INPUT_AVAIL)
  48 #define output_ready()          (uart6850_status()&OUTPUT_READY)
  49
  50 static void uart6850_cmd(unsigned char cmd)
  51 {
  52         outb(cmd, COMDPORT);
  53 }
  54
  55 static int uart6850_read(void)
  56 {
  57         return inb(DATAPORT);
  58 }
  59
  60 static void uart6850_write(unsigned char byte)
  61 {
  62         outb(byte, DATAPORT);
  63 }
  64
  65 #define OUTPUT_READY    0x02    /* Mask for data ready Bit */
  66 #define INPUT_AVAIL     0x01    /* Mask for Data Send Ready Bit */
  67
  68 #define UART_RESET      0x95
  69 #define UART_MODE_ON    0x03
  70
  71 static int uart6850_opened;
  72 static int uart6850_irq;
  73 static int uart6850_detected;
  74 static int my_dev;
  75 static DEFINE_SPINLOCK(lock);
  76
  77 static void (*midi_input_intr) (int dev, unsigned char data);
  78 static void poll_uart6850(unsigned long dummy);
  79
  80
  81 static DEFINE_TIMER(uart6850_timer, poll_uart6850, 0, 0);
  82
  83 static void uart6850_input_loop(void)
  84 {
  85         int count = 10;
  86
  87         while (count)
  88         {
  89                 /*
  90                  * Not timed out
  91                  */
  92                 if (input_avail())
  93                 {
  94                         unsigned char c = uart6850_read();
  95                         count = 100;
  96                         if (uart6850_opened & OPEN_READ)
  97                                 midi_input_intr(my_dev, c);
  98                 }
  99                 else
 100                 {
 101                         while (!input_avail() && count)
 102                                 count--;
 103                 }
 104         }
 105 }
 106
 107 static irqreturn_t m6850intr(int irq, void *dev_id, struct pt_regs *dummy)
 108 {
 109         if (input_avail())
 110                 uart6850_input_loop();
 111         return IRQ_HANDLED;
 112 }
 113
 114 /*
 115  *      It looks like there is no input interrupts in the UART mode. Let's try
 116  *      polling.
 117  */
 118
 119 static void poll_uart6850(unsigned long dummy)
 120 {
 121         unsigned long flags;
 122
 123         if (!(uart6850_opened & OPEN_READ))
 124                 return;         /* Device has been closed */
 125
 126         spin_lock_irqsave(&lock,flags);
 127         if (input_avail())
 128                 uart6850_input_loop();
 129
 130         uart6850_timer.expires = 1 + jiffies;
 131         add_timer(&uart6850_timer);
 132
 133         /*
 134          *      Come back later
 135          */
 136
 137         spin_unlock_irqrestore(&lock,flags);
 138 }
 139
 140 static int uart6850_open(int dev, int mode,
 141               void            (*input) (int dev, unsigned char data),
 142               void            (*output) (int dev)
 143 )
 144 {
 145         if (uart6850_opened)
 146         {
 147 /*                printk("Midi6850: Midi busy\n");*/
 148                   return -EBUSY;
 149         };
 150
 151         uart6850_cmd(UART_RESET);
 152         uart6850_input_loop();
 153         midi_input_intr = input;
 154         uart6850_opened = mode;
 155         poll_uart6850(0);       /*
 156                                  * Enable input polling
 157                                  */
 158
 159         return 0;
 160 }
 161
 162 static void uart6850_close(int dev)
 163 {
 164         uart6850_cmd(UART_MODE_ON);
 165         del_timer(&uart6850_timer);
 166         uart6850_opened = 0;
 167 }
 168
 169 static int uart6850_out(int dev, unsigned char midi_byte)
 170 {
 171         int timeout;
 172         unsigned long flags;
 173
 174         /*
 175          * Test for input since pending input seems to block the output.
 176          */
 177
 178         spin_lock_irqsave(&lock,flags);
 179
 180         if (input_avail())
 181                 uart6850_input_loop();
 182
 183         spin_unlock_irqrestore(&lock,flags);
 184
 185         /*
 186          * Sometimes it takes about 13000 loops before the output becomes ready
 187          * (After reset). Normally it takes just about 10 loops.
 188          */
 189
 190         for (timeout = 30000; timeout > 0 && !output_ready(); timeout--);       /*
 191                                                                                  * Wait
 192                                                                                  */
 193         if (!output_ready())
 194         {
 195                 printk(KERN_WARNING "Midi6850: Timeout\n");
 196                 return 0;
 197         }
 198         uart6850_write(midi_byte);
 199         return 1;
 200 }
 201
 202 static inline int uart6850_command(int dev, unsigned char *midi_byte)
 203 {
 204         return 1;
 205 }
 206
 207 static inline int uart6850_start_read(int dev)
 208 {
 209         return 0;
 210 }
 211
 212 static inline int uart6850_end_read(int dev)
 213 {
 214         return 0;
 215 }
 216
 217 static inline void uart6850_kick(int dev)
 218 {
 219 }
 220
 221 static inline int uart6850_buffer_status(int dev)
 222 {
 223         return 0;               /*
 224                                  * No data in buffers
 225                                  */
 226 }
 227
 228 #define MIDI_SYNTH_NAME "6850 UART Midi"
 229 #define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT
 230 #include "midi_synth.h"
 231
 232 static struct midi_operations uart6850_operations =
 233 {
 234         .owner          = THIS_MODULE,
 235         .info           = {"6850 UART", 0, 0, SNDCARD_UART6850},
 236         .converter      = &std_midi_synth,
 237         .in_info        = {0},
 238         .open           = uart6850_open,
 239         .close          = uart6850_close,
 240         .outputc        = uart6850_out,
 241         .start_read     = uart6850_start_read,
 242         .end_read       = uart6850_end_read,
 243         .kick           = uart6850_kick,
 244         .command        = uart6850_command,
 245         .buffer_status  = uart6850_buffer_status
 246 };
 247
 248
 249 static void __init attach_uart6850(struct address_info *hw_config)
 250 {
 251         int ok, timeout;
 252         unsigned long   flags;
 253
 254         if (!uart6850_detected)
 255                 return;
 256
 257         if ((my_dev = sound_alloc_mididev()) == -1)
 258         {
 259                 printk(KERN_INFO "uart6850: Too many midi devices detected\n");
 260                 return;
 261         }
 262         uart6850_base = hw_config->io_base;
 263         uart6850_osp = hw_config->osp;
 264         uart6850_irq = hw_config->irq;
 265
 266         spin_lock_irqsave(&lock,flags);
 267
 268         for (timeout = 30000; timeout > 0 && !output_ready(); timeout--);       /*
 269                                                                                  * Wait
 270                                                                                  */
 271         uart6850_cmd(UART_MODE_ON);
 272         ok = 1;
 273         spin_unlock_irqrestore(&lock,flags);
 274
 275         conf_printf("6850 Midi Interface", hw_config);
 276
 277         std_midi_synth.midi_dev = my_dev;
 278         hw_config->slots[4] = my_dev;
 279         midi_devs[my_dev] = &uart6850_operations;
 280         sequencer_init();
 281 }
 282
 283 static inline int reset_uart6850(void)
 284 {
 285         uart6850_read();
 286         return 1;               /*
 287                                  * OK
 288                                  */
 289 }
 290
 291 static int __init probe_uart6850(struct address_info *hw_config)
 292 {
 293         int ok;
 294
 295         uart6850_osp = hw_config->osp;
 296         uart6850_base = hw_config->io_base;
 297         uart6850_irq = hw_config->irq;
 298
 299         if (request_irq(uart6850_irq, m6850intr, 0, "MIDI6850", NULL) < 0)
 300                 return 0;
 301
 302         ok = reset_uart6850();
 303         uart6850_detected = ok;
 304         return ok;
 305 }
 306
 307 static void __exit unload_uart6850(struct address_info *hw_config)
 308 {
 309         free_irq(hw_config->irq, NULL);
 310         sound_unload_mididev(hw_config->slots[4]);
 311 }
 312
 313 static struct address_info cfg_mpu;
 314
 315 static int __initdata io = -1;
 316 static int __initdata irq = -1;
 317
 318 module_param(io, int, 0);
 319 module_param(irq, int, 0);
 320
 321 static int __init init_uart6850(void)
 322 {
 323         cfg_mpu.io_base = io;
 324         cfg_mpu.irq = irq;
 325
 326         if (cfg_mpu.io_base == -1 || cfg_mpu.irq == -1) {
 327                 printk(KERN_INFO "uart6850: irq and io must be set.\n");
 328                 return -EINVAL;
 329         }
 330
 331         if (probe_uart6850(&cfg_mpu))
 332                 return -ENODEV;
 333         attach_uart6850(&cfg_mpu);
 334
 335         return 0;
 336 }
 337
 338 static void __exit cleanup_uart6850(void)
 339 {
 340         unload_uart6850(&cfg_mpu);
 341 }
 342
 343 module_init(init_uart6850);
 344 module_exit(cleanup_uart6850);
 345
 346 #ifndef MODULE
 347 static int __init setup_uart6850(char *str)
 348 {
 349         /* io, irq */
 350         int ints[3];
 351
 352         str = get_options(str, ARRAY_SIZE(ints), ints);
 353
 354         io = ints[1];
 355         irq = ints[2];
 356
 357         return 1;
 358 }
 359 __setup("uart6850=", setup_uart6850);
 360 #endif
 361 MODULE_LICENSE("GPL");