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/module.h>
26
27 #include "sound_config.h"
28
29 #include "mpu401.h"
30
31 typedef struct uart401_devc
32 {
33 int base;
34 int irq;
35 int *osp;
36 void (*midi_input_intr) (int dev, unsigned char data);
37 int opened, disabled;
38 volatile unsigned char input_byte;
39 int my_dev;
40 int share_irq;
41 }
42 uart401_devc;
43
44 #define DATAPORT (devc->base)
45 #define COMDPORT (devc->base+1)
46 #define STATPORT (devc->base+1)
47
48 static int uart401_status(uart401_devc * devc)
49 {
50 return inb(STATPORT);
51 }
52
53 #define input_avail(devc) (!(uart401_status(devc)&INPUT_AVAIL))
54 #define output_ready(devc) (!(uart401_status(devc)&OUTPUT_READY))
55
56 static void uart401_cmd(uart401_devc * devc, unsigned char cmd)
57 {
58 outb((cmd), COMDPORT);
59 }
60
61 static int uart401_read(uart401_devc * devc)
62 {
63 return inb(DATAPORT);
64 }
65
66 static void uart401_write(uart401_devc * devc, unsigned char byte)
67 {
68 outb((byte), DATAPORT);
69 }
70
71 #define OUTPUT_READY 0x40
72 #define INPUT_AVAIL 0x80
73 #define MPU_ACK 0xFE
74 #define MPU_RESET 0xFF
75 #define UART_MODE_ON 0x3F
76
77 static int reset_uart401(uart401_devc * devc);
78 static void enter_uart_mode(uart401_devc * devc);
79
80 static void uart401_input_loop(uart401_devc * devc)
81 {
82 int work_limit=30000;
83
84 while (input_avail(devc) && --work_limit)
85 {
86 unsigned char c = uart401_read(devc);
87
88 if (c == MPU_ACK)
89 devc->input_byte = c;
90 else if (devc->opened & OPEN_READ && devc->midi_input_intr)
91 devc->midi_input_intr(devc->my_dev, c);
92 }
93 if(work_limit==0)
94 printk(KERN_WARNING "Too much work in interrupt on uart401 (0x%X). UART jabbering ??\n", devc->base);
95 }
96
97 void uart401intr(int irq, void *dev_id, struct pt_regs *dummy)
98 {
99 uart401_devc *devc = dev_id;
100
101 if (devc == NULL)
102 {
103 printk(KERN_ERR "uart401: bad devc\n");
104 return;
105 }
106
107 if (input_avail(devc))
108 uart401_input_loop(devc);
109 }
110
111 static int
112 uart401_open(int dev, int mode,
113 void (*input) (int dev, unsigned char data),
114 void (*output) (int dev)
115 )
116 {
117 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
118
119 if (devc->opened)
120 return -EBUSY;
121
122 /* Flush the UART */
123
124 while (input_avail(devc))
125 uart401_read(devc);
126
127 devc->midi_input_intr = input;
128 devc->opened = mode;
129 enter_uart_mode(devc);
130 devc->disabled = 0;
131
132 return 0;
133 }
134
135 static void uart401_close(int dev)
136 {
137 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
138
139 reset_uart401(devc);
140 devc->opened = 0;
141 }
142
143 static int uart401_out(int dev, unsigned char midi_byte)
144 {
145 int timeout;
146 unsigned long flags;
147 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
148
149 if (devc->disabled)
150 return 1;
151 /*
152 * Test for input since pending input seems to block the output.
153 */
154
155 save_flags(flags);
156 cli();
157
158 if (input_avail(devc))
159 uart401_input_loop(devc);
160
161 restore_flags(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 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 save_flags(flags);
226 cli();
227 for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
228
229 devc->input_byte = 0;
230 uart401_cmd(devc, UART_MODE_ON);
231
232 ok = 0;
233 for (timeout = 50000; timeout > 0 && !ok; timeout--)
234 if (devc->input_byte == MPU_ACK)
235 ok = 1;
236 else if (input_avail(devc))
237 if (uart401_read(devc) == MPU_ACK)
238 ok = 1;
239
240 restore_flags(flags);
241 }
242
243 static int reset_uart401(uart401_devc * devc)
244 {
245 int ok, timeout, n;
246
247 /*
248 * Send the RESET command. Try again if no success at the first time.
249 */
250
251 ok = 0;
252
253 for (n = 0; n < 2 && !ok; n++)
254 {
255 for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
256 devc->input_byte = 0;
257 uart401_cmd(devc, MPU_RESET);
258
259 /*
260 * Wait at least 25 msec. This method is not accurate so let's make the
261 * loop bit longer. Cannot sleep since this is called during boot.
262 */
263
264 for (timeout = 50000; timeout > 0 && !ok; timeout--)
265 {
266 if (devc->input_byte == MPU_ACK) /* Interrupt */
267 ok = 1;
268 else if (input_avail(devc))
269 {
270 if (uart401_read(devc) == MPU_ACK)
271 ok = 1;
272 }
273 }
274 }
275
276
277 if (ok)
278 {
279 DEB(printk("Reset UART401 OK\n"));
280 }
281 else
282 DDB(printk("Reset UART401 failed - No hardware detected.\n"));
283
284 if (ok)
285 uart401_input_loop(devc); /*
286 * Flush input before enabling interrupts
287 */
288
289 return ok;
290 }
291
292 int probe_uart401(struct address_info *hw_config, struct module *owner)
293 {
294 uart401_devc *devc;
295 char *name = "MPU-401 (UART) MIDI";
296 int ok = 0;
297 unsigned long flags;
298
299 DDB(printk("Entered probe_uart401()\n"));
300
301 /* Default to "not found" */
302 hw_config->slots[4] = -1;
303
304 if (!request_region(hw_config->io_base, 4, "MPU-401 UART")) {
305 printk(KERN_INFO "uart401: could not request_region(%d, 4)\n", hw_config->io_base);
306 return 0;
307 }
308
309 devc = kmalloc(sizeof(uart401_devc), GFP_KERNEL);
310 if (!devc) {
311 printk(KERN_WARNING "uart401: Can't allocate memory\n");
312 goto cleanup_region;
313 }
314
315 devc->base = hw_config->io_base;
316 devc->irq = hw_config->irq;
317 devc->osp = hw_config->osp;
318 devc->midi_input_intr = NULL;
319 devc->opened = 0;
320 devc->input_byte = 0;
321 devc->my_dev = 0;
322 devc->share_irq = 0;
323
324 save_flags(flags);
325 cli();
326 ok = reset_uart401(devc);
327 restore_flags(flags);
328
329 if (!ok)
330 goto cleanup_devc;
331
332 if (hw_config->name)
333 name = hw_config->name;
334
335 if (devc->irq < 0) {
336 devc->share_irq = 1;
337 devc->irq *= -1;
338 } else
339 devc->share_irq = 0;
340
341 if (!devc->share_irq)
342 if (request_irq(devc->irq, uart401intr, 0, "MPU-401 UART", devc) < 0) {
343 printk(KERN_WARNING "uart401: Failed to allocate IRQ%d\n", devc->irq);
344 devc->share_irq = 1;
345 }
346 devc->my_dev = sound_alloc_mididev();
347 enter_uart_mode(devc);
348
349 if (devc->my_dev == -1) {
350 printk(KERN_INFO "uart401: Too many midi devices detected\n");
351 goto cleanup_irq;
352 }
353 conf_printf(name, hw_config);
354 std_midi_synth.midi_dev = devc->my_dev;
355 midi_devs[devc->my_dev] = kmalloc(sizeof(struct midi_operations), GFP_KERNEL);
356 if (!midi_devs[devc->my_dev]) {
357 printk(KERN_ERR "uart401: Failed to allocate memory\n");
358 goto cleanup_unload_mididev;
359 }
360 memcpy(midi_devs[devc->my_dev], &uart401_operations, sizeof(struct midi_operations));
361
362 if (owner)
363 midi_devs[devc->my_dev]->owner = owner;
364
365 midi_devs[devc->my_dev]->devc = devc;
366 midi_devs[devc->my_dev]->converter = kmalloc(sizeof(struct synth_operations), GFP_KERNEL);
367 if (!midi_devs[devc->my_dev]->converter) {
368 printk(KERN_WARNING "uart401: Failed to allocate memory\n");
369 goto cleanup_midi_devs;
370 }
371 memcpy(midi_devs[devc->my_dev]->converter, &std_midi_synth, sizeof(struct synth_operations));
372 strcpy(midi_devs[devc->my_dev]->info.name, name);
373 midi_devs[devc->my_dev]->converter->id = "UART401";
374 hw_config->slots[4] = devc->my_dev;
375 sequencer_init();
376 devc->opened = 0;
377 return 1;
378 cleanup_midi_devs:
379 kfree(midi_devs[devc->my_dev]);
380 cleanup_unload_mididev:
381 sound_unload_mididev(devc->my_dev);
382 cleanup_irq:
383 if (!devc->share_irq)
384 free_irq(devc->irq, devc);
385 cleanup_devc:
386 kfree(devc);
387 cleanup_region:
388 release_region(hw_config->io_base, 4);
389 return 0;
390 }
391
392 void unload_uart401(struct address_info *hw_config)
393 {
394 uart401_devc *devc;
395 int n=hw_config->slots[4];
396
397 /* Not set up */
398 if(n==-1 || midi_devs[n]==NULL)
399 return;
400
401 /* Not allocated (erm ??) */
402
403 devc = midi_devs[hw_config->slots[4]]->devc;
404 if (devc == NULL)
405 return;
406
407 reset_uart401(devc);
408 release_region(hw_config->io_base, 4);
409
410 if (!devc->share_irq)
411 free_irq(devc->irq, devc);
412 if (devc)
413 {
414 kfree(midi_devs[devc->my_dev]->converter);
415 kfree(midi_devs[devc->my_dev]);
416 kfree(devc);
417 devc = NULL;
418 }
419 /* This kills midi_devs[x] */
420 sound_unload_mididev(hw_config->slots[4]);
421 }
422
423 EXPORT_SYMBOL(probe_uart401);
424 EXPORT_SYMBOL(unload_uart401);
425 EXPORT_SYMBOL(uart401intr);
426
427 static struct address_info cfg_mpu;
428
429 static int __initdata io = -1;
430 static int __initdata irq = -1;
431
432 MODULE_PARM(io, "i");
433 MODULE_PARM(irq, "i");
434
435
436 static int __init init_uart401(void)
437 {
438 cfg_mpu.irq = irq;
439 cfg_mpu.io_base = io;
440
441 /* Can be loaded either for module use or to provide functions
442 to others */
443 if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1) {
444 printk(KERN_INFO "MPU-401 UART driver Copyright (C) Hannu Savolainen 1993-1997");
445 if (!probe_uart401(&cfg_mpu, THIS_MODULE))
446 return -ENODEV;
447 }
448
449 return 0;
450 }
451
452 static void __exit cleanup_uart401(void)
453 {
454 if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1)
455 unload_uart401(&cfg_mpu);
456 }
457
458 module_init(init_uart401);
459 module_exit(cleanup_uart401);
460
461 #ifndef MODULE
462 static int __init setup_uart401(char *str)
463 {
464 /* io, irq */
465 int ints[3];
466
467 str = get_options(str, ARRAY_SIZE(ints), ints);
468
469 io = ints[1];
470 irq = ints[2];
471
472 return 1;
473 }
474
475 __setup("uart401=", setup_uart401);
476 #endif
477
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