1 /*
2 * sound/oss/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
uart401_status(uart401_devc * devc)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
uart401_cmd(uart401_devc * devc,unsigned char cmd)58 static void uart401_cmd(uart401_devc * devc, unsigned char cmd)
59 {
60 outb((cmd), COMDPORT);
61 }
62
uart401_read(uart401_devc * devc)63 static int uart401_read(uart401_devc * devc)
64 {
65 return inb(DATAPORT);
66 }
67
uart401_write(uart401_devc * devc,unsigned char byte)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
uart401_input_loop(uart401_devc * devc)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
uart401intr(int irq,void * dev_id)99 irqreturn_t uart401intr(int irq, void *dev_id)
100 {
101 uart401_devc *devc = dev_id;
102
103 if (devc == NULL)
104 {
105 printk(KERN_ERR "uart401: bad devc\n");
106 return IRQ_NONE;
107 }
108
109 if (input_avail(devc))
110 uart401_input_loop(devc);
111 return IRQ_HANDLED;
112 }
113
114 static int
uart401_open(int dev,int mode,void (* input)(int dev,unsigned char data),void (* output)(int dev))115 uart401_open(int dev, int mode,
116 void (*input) (int dev, unsigned char data),
117 void (*output) (int dev)
118 )
119 {
120 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
121
122 if (devc->opened)
123 return -EBUSY;
124
125 /* Flush the UART */
126
127 while (input_avail(devc))
128 uart401_read(devc);
129
130 devc->midi_input_intr = input;
131 devc->opened = mode;
132 enter_uart_mode(devc);
133 devc->disabled = 0;
134
135 return 0;
136 }
137
uart401_close(int dev)138 static void uart401_close(int dev)
139 {
140 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
141
142 reset_uart401(devc);
143 devc->opened = 0;
144 }
145
uart401_out(int dev,unsigned char midi_byte)146 static int uart401_out(int dev, unsigned char midi_byte)
147 {
148 int timeout;
149 unsigned long flags;
150 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
151
152 if (devc->disabled)
153 return 1;
154 /*
155 * Test for input since pending input seems to block the output.
156 */
157
158 spin_lock_irqsave(&devc->lock,flags);
159 if (input_avail(devc))
160 uart401_input_loop(devc);
161
162 spin_unlock_irqrestore(&devc->lock,flags);
163
164 /*
165 * Sometimes it takes about 13000 loops before the output becomes ready
166 * (After reset). Normally it takes just about 10 loops.
167 */
168
169 for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
170
171 if (!output_ready(devc))
172 {
173 printk(KERN_WARNING "uart401: Timeout - Device not responding\n");
174 devc->disabled = 1;
175 reset_uart401(devc);
176 enter_uart_mode(devc);
177 return 1;
178 }
179 uart401_write(devc, midi_byte);
180 return 1;
181 }
182
uart401_start_read(int dev)183 static inline int uart401_start_read(int dev)
184 {
185 return 0;
186 }
187
uart401_end_read(int dev)188 static inline int uart401_end_read(int dev)
189 {
190 return 0;
191 }
192
uart401_kick(int dev)193 static inline void uart401_kick(int dev)
194 {
195 }
196
uart401_buffer_status(int dev)197 static inline int uart401_buffer_status(int dev)
198 {
199 return 0;
200 }
201
202 #define MIDI_SYNTH_NAME "MPU-401 UART"
203 #define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT
204 #include "midi_synth.h"
205
206 static const struct midi_operations uart401_operations =
207 {
208 .owner = THIS_MODULE,
209 .info = {"MPU-401 (UART) MIDI", 0, 0, SNDCARD_MPU401},
210 .converter = &std_midi_synth,
211 .in_info = {0},
212 .open = uart401_open,
213 .close = uart401_close,
214 .outputc = uart401_out,
215 .start_read = uart401_start_read,
216 .end_read = uart401_end_read,
217 .kick = uart401_kick,
218 .buffer_status = uart401_buffer_status,
219 };
220
enter_uart_mode(uart401_devc * devc)221 static void enter_uart_mode(uart401_devc * devc)
222 {
223 int ok, timeout;
224 unsigned long flags;
225
226 spin_lock_irqsave(&devc->lock,flags);
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 spin_unlock_irqrestore(&devc->lock,flags);
241 }
242
reset_uart401(uart401_devc * devc)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
probe_uart401(struct address_info * hw_config,struct module * owner)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 spin_lock_init(&devc->lock);
324
325 spin_lock_irqsave(&devc->lock,flags);
326 ok = reset_uart401(devc);
327 spin_unlock_irqrestore(&devc->lock,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 midi_devs[devc->my_dev] = kmalloc(sizeof(struct midi_operations), GFP_KERNEL);
355 if (!midi_devs[devc->my_dev]) {
356 printk(KERN_ERR "uart401: Failed to allocate memory\n");
357 goto cleanup_unload_mididev;
358 }
359 memcpy(midi_devs[devc->my_dev], &uart401_operations, sizeof(struct midi_operations));
360
361 if (owner)
362 midi_devs[devc->my_dev]->owner = owner;
363
364 midi_devs[devc->my_dev]->devc = devc;
365 midi_devs[devc->my_dev]->converter = kmalloc(sizeof(struct synth_operations), GFP_KERNEL);
366 if (!midi_devs[devc->my_dev]->converter) {
367 printk(KERN_WARNING "uart401: Failed to allocate memory\n");
368 goto cleanup_midi_devs;
369 }
370 memcpy(midi_devs[devc->my_dev]->converter, &std_midi_synth, sizeof(struct synth_operations));
371 strcpy(midi_devs[devc->my_dev]->info.name, name);
372 midi_devs[devc->my_dev]->converter->id = "UART401";
373 midi_devs[devc->my_dev]->converter->midi_dev = devc->my_dev;
374
375 if (owner)
376 midi_devs[devc->my_dev]->converter->owner = owner;
377
378 hw_config->slots[4] = devc->my_dev;
379 sequencer_init();
380 devc->opened = 0;
381 return 1;
382 cleanup_midi_devs:
383 kfree(midi_devs[devc->my_dev]);
384 cleanup_unload_mididev:
385 sound_unload_mididev(devc->my_dev);
386 cleanup_irq:
387 if (!devc->share_irq)
388 free_irq(devc->irq, devc);
389 cleanup_devc:
390 kfree(devc);
391 cleanup_region:
392 release_region(hw_config->io_base, 4);
393 return 0;
394 }
395
unload_uart401(struct address_info * hw_config)396 void unload_uart401(struct address_info *hw_config)
397 {
398 uart401_devc *devc;
399 int n=hw_config->slots[4];
400
401 /* Not set up */
402 if(n==-1 || midi_devs[n]==NULL)
403 return;
404
405 /* Not allocated (erm ??) */
406
407 devc = midi_devs[hw_config->slots[4]]->devc;
408 if (devc == NULL)
409 return;
410
411 reset_uart401(devc);
412 release_region(hw_config->io_base, 4);
413
414 if (!devc->share_irq)
415 free_irq(devc->irq, devc);
416 if (devc)
417 {
418 kfree(midi_devs[devc->my_dev]->converter);
419 kfree(midi_devs[devc->my_dev]);
420 kfree(devc);
421 devc = NULL;
422 }
423 /* This kills midi_devs[x] */
424 sound_unload_mididev(hw_config->slots[4]);
425 }
426
427 EXPORT_SYMBOL(probe_uart401);
428 EXPORT_SYMBOL(unload_uart401);
429 EXPORT_SYMBOL(uart401intr);
430
431 static struct address_info cfg_mpu;
432
433 static int io = -1;
434 static int irq = -1;
435
436 module_param(io, int, 0444);
437 module_param(irq, int, 0444);
438
439
init_uart401(void)440 static int __init init_uart401(void)
441 {
442 cfg_mpu.irq = irq;
443 cfg_mpu.io_base = io;
444
445 /* Can be loaded either for module use or to provide functions
446 to others */
447 if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1) {
448 printk(KERN_INFO "MPU-401 UART driver Copyright (C) Hannu Savolainen 1993-1997");
449 if (!probe_uart401(&cfg_mpu, THIS_MODULE))
450 return -ENODEV;
451 }
452
453 return 0;
454 }
455
cleanup_uart401(void)456 static void __exit cleanup_uart401(void)
457 {
458 if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1)
459 unload_uart401(&cfg_mpu);
460 }
461
462 module_init(init_uart401);
463 module_exit(cleanup_uart401);
464
465 #ifndef MODULE
setup_uart401(char * str)466 static int __init setup_uart401(char *str)
467 {
468 /* io, irq */
469 int ints[3];
470
471 str = get_options(str, ARRAY_SIZE(ints), ints);
472
473 io = ints[1];
474 irq = ints[2];
475
476 return 1;
477 }
478
479 __setup("uart401=", setup_uart401);
480 #endif
481 MODULE_LICENSE("GPL");
482