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 struct timer_list uart6850_timer =
  82                 TIMER_INITIALIZER(poll_uart6850, 0, 0);
  83
  84 static void uart6850_input_loop(void)
  85 {
  86         int count = 10;
  87
  88         while (count)
  89         {
  90                 /*
  91                  * Not timed out
  92                  */
  93                 if (input_avail())
  94                 {
  95                         unsigned char c = uart6850_read();
  96                         count = 100;
  97                         if (uart6850_opened & OPEN_READ)
  98                                 midi_input_intr(my_dev, c);
  99                 }
 100                 else
 101                 {
 102                         while (!input_avail() && count)
 103                                 count--;
 104                 }
 105         }
 106 }
 107
 108 static irqreturn_t m6850intr(int irq, void *dev_id, struct pt_regs *dummy)
 109 {
 110         if (input_avail())
 111                 uart6850_input_loop();
 112         return IRQ_HANDLED;
 113 }
 114
 115 /*
 116  *      It looks like there is no input interrupts in the UART mode. Let's try
 117  *      polling.
 118  */
 119
 120 static void poll_uart6850(unsigned long dummy)
 121 {
 122         unsigned long flags;
 123
 124         if (!(uart6850_opened & OPEN_READ))
 125                 return;         /* Device has been closed */
 126
 127         spin_lock_irqsave(&lock,flags);
 128         if (input_avail())
 129                 uart6850_input_loop();
 130
 131         uart6850_timer.expires = 1 + jiffies;
 132         add_timer(&uart6850_timer);
 133
 134         /*
 135          *      Come back later
 136          */
 137
 138         spin_unlock_irqrestore(&lock,flags);
 139 }
 140
 141 static int uart6850_open(int dev, int mode,
 142               void            (*input) (int dev, unsigned char data),
 143               void            (*output) (int dev)
 144 )
 145 {
 146         if (uart6850_opened)
 147         {
 148 /*                printk("Midi6850: Midi busy\n");*/
 149                   return -EBUSY;
 150         };
 151
 152         uart6850_cmd(UART_RESET);
 153         uart6850_input_loop();
 154         midi_input_intr = input;
 155         uart6850_opened = mode;
 156         poll_uart6850(0);       /*
 157                                  * Enable input polling
 158                                  */
 159
 160         return 0;
 161 }
 162
 163 static void uart6850_close(int dev)
 164 {
 165         uart6850_cmd(UART_MODE_ON);
 166         del_timer(&uart6850_timer);
 167         uart6850_opened = 0;
 168 }
 169
 170 static int uart6850_out(int dev, unsigned char midi_byte)
 171 {
 172         int timeout;
 173         unsigned long flags;
 174
 175         /*
 176          * Test for input since pending input seems to block the output.
 177          */
 178
 179         spin_lock_irqsave(&lock,flags);
 180
 181         if (input_avail())
 182                 uart6850_input_loop();
 183
 184         spin_unlock_irqrestore(&lock,flags);
 185
 186         /*
 187          * Sometimes it takes about 13000 loops before the output becomes ready
 188          * (After reset). Normally it takes just about 10 loops.
 189          */
 190
 191         for (timeout = 30000; timeout > 0 && !output_ready(); timeout--);       /*
 192                                                                                  * Wait
 193                                                                                  */
 194         if (!output_ready())
 195         {
 196                 printk(KERN_WARNING "Midi6850: Timeout\n");
 197                 return 0;
 198         }
 199         uart6850_write(midi_byte);
 200         return 1;
 201 }
 202
 203 static inline int uart6850_command(int dev, unsigned char *midi_byte)
 204 {
 205         return 1;
 206 }
 207
 208 static inline int uart6850_start_read(int dev)
 209 {
 210         return 0;
 211 }
 212
 213 static inline int uart6850_end_read(int dev)
 214 {
 215         return 0;
 216 }
 217
 218 static inline void uart6850_kick(int dev)
 219 {
 220 }
 221
 222 static inline int uart6850_buffer_status(int dev)
 223 {
 224         return 0;               /*
 225                                  * No data in buffers
 226                                  */
 227 }
 228
 229 #define MIDI_SYNTH_NAME "6850 UART Midi"
 230 #define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT
 231 #include "midi_synth.h"
 232
 233 static struct midi_operations uart6850_operations =
 234 {
 235         .owner          = THIS_MODULE,
 236         .info           = {"6850 UART", 0, 0, SNDCARD_UART6850},
 237         .converter      = &std_midi_synth,
 238         .in_info        = {0},
 239         .open           = uart6850_open,
 240         .close          = uart6850_close,
 241         .outputc        = uart6850_out,
 242         .start_read     = uart6850_start_read,
 243         .end_read       = uart6850_end_read,
 244         .kick           = uart6850_kick,
 245         .command        = uart6850_command,
 246         .buffer_status  = uart6850_buffer_status
 247 };
 248
 249
 250 static void __init attach_uart6850(struct address_info *hw_config)
 251 {
 252         int ok, timeout;
 253         unsigned long   flags;
 254
 255         if (!uart6850_detected)
 256                 return;
 257
 258         if ((my_dev = sound_alloc_mididev()) == -1)
 259         {
 260                 printk(KERN_INFO "uart6850: Too many midi devices detected\n");
 261                 return;
 262         }
 263         uart6850_base = hw_config->io_base;
 264         uart6850_osp = hw_config->osp;
 265         uart6850_irq = hw_config->irq;
 266
 267         spin_lock_irqsave(&lock,flags);
 268
 269         for (timeout = 30000; timeout > 0 && !output_ready(); timeout--);       /*
 270                                                                                  * Wait
 271                                                                                  */
 272         uart6850_cmd(UART_MODE_ON);
 273         ok = 1;
 274         spin_unlock_irqrestore(&lock,flags);
 275
 276         conf_printf("6850 Midi Interface", hw_config);
 277
 278         std_midi_synth.midi_dev = my_dev;
 279         hw_config->slots[4] = my_dev;
 280         midi_devs[my_dev] = &uart6850_operations;
 281         sequencer_init();
 282 }
 283
 284 static inline int reset_uart6850(void)
 285 {
 286         uart6850_read();
 287         return 1;               /*
 288                                  * OK
 289                                  */
 290 }
 291
 292 static int __init probe_uart6850(struct address_info *hw_config)
 293 {
 294         int ok;
 295
 296         uart6850_osp = hw_config->osp;
 297         uart6850_base = hw_config->io_base;
 298         uart6850_irq = hw_config->irq;
 299
 300         if (request_irq(uart6850_irq, m6850intr, 0, "MIDI6850", NULL) < 0)
 301                 return 0;
 302
 303         ok = reset_uart6850();
 304         uart6850_detected = ok;
 305         return ok;
 306 }
 307
 308 static void __exit unload_uart6850(struct address_info *hw_config)
 309 {
 310         free_irq(hw_config->irq, NULL);
 311         sound_unload_mididev(hw_config->slots[4]);
 312 }
 313
 314 static struct address_info cfg_mpu;
 315
 316 static int __initdata io = -1;
 317 static int __initdata irq = -1;
 318
 319 module_param(io, int, 0);
 320 module_param(irq, int, 0);
 321
 322 static int __init init_uart6850(void)
 323 {
 324         cfg_mpu.io_base = io;
 325         cfg_mpu.irq = irq;
 326
 327         if (cfg_mpu.io_base == -1 || cfg_mpu.irq == -1) {
 328                 printk(KERN_INFO "uart6850: irq and io must be set.\n");
 329                 return -EINVAL;
 330         }
 331
 332         if (probe_uart6850(&cfg_mpu))
 333                 return -ENODEV;
 334         attach_uart6850(&cfg_mpu);
 335
 336         return 0;
 337 }
 338
 339 static void __exit cleanup_uart6850(void)
 340 {
 341         unload_uart6850(&cfg_mpu);
 342 }
 343
 344 module_init(init_uart6850);
 345 module_exit(cleanup_uart6850);
 346
 347 #ifndef MODULE
 348 static int __init setup_uart6850(char *str)
 349 {
 350         /* io, irq */
 351         int ints[3];
 352
 353         str = get_options(str, ARRAY_SIZE(ints), ints);
 354
 355         io = ints[1];
 356         irq = ints[2];
 357
 358         return 1;
 359 }
 360 __setup("uart6850=", setup_uart6850);
 361 #endif
 362 MODULE_LICENSE("GPL");