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/slab.h>
28 #include <linux/spinlock.h>
29 #include "sound_config.h"
30
31 #include "mpu401.h"
32
33 typedef struct uart401_devc
34 {
35 int base;
36 int irq;
37 int *osp;
38 void (*midi_input_intr) (int dev, unsigned char data);
39 int opened, disabled;
40 volatile unsigned char input_byte;
41 int my_dev;
42 int share_irq;
43 spinlock_t lock;
44 }
45 uart401_devc;
46
47 #define DATAPORT (devc->base)
48 #define COMDPORT (devc->base+1)
49 #define STATPORT (devc->base+1)
50
uart401_status(uart401_devc * devc)51 static int uart401_status(uart401_devc * devc)
52 {
53 return inb(STATPORT);
54 }
55
56 #define input_avail(devc) (!(uart401_status(devc)&INPUT_AVAIL))
57 #define output_ready(devc) (!(uart401_status(devc)&OUTPUT_READY))
58
uart401_cmd(uart401_devc * devc,unsigned char cmd)59 static void uart401_cmd(uart401_devc * devc, unsigned char cmd)
60 {
61 outb((cmd), COMDPORT);
62 }
63
uart401_read(uart401_devc * devc)64 static int uart401_read(uart401_devc * devc)
65 {
66 return inb(DATAPORT);
67 }
68
uart401_write(uart401_devc * devc,unsigned char byte)69 static void uart401_write(uart401_devc * devc, unsigned char byte)
70 {
71 outb((byte), DATAPORT);
72 }
73
74 #define OUTPUT_READY 0x40
75 #define INPUT_AVAIL 0x80
76 #define MPU_ACK 0xFE
77 #define MPU_RESET 0xFF
78 #define UART_MODE_ON 0x3F
79
80 static int reset_uart401(uart401_devc * devc);
81 static void enter_uart_mode(uart401_devc * devc);
82
uart401_input_loop(uart401_devc * devc)83 static void uart401_input_loop(uart401_devc * devc)
84 {
85 int work_limit=30000;
86
87 while (input_avail(devc) && --work_limit)
88 {
89 unsigned char c = uart401_read(devc);
90
91 if (c == MPU_ACK)
92 devc->input_byte = c;
93 else if (devc->opened & OPEN_READ && devc->midi_input_intr)
94 devc->midi_input_intr(devc->my_dev, c);
95 }
96 if(work_limit==0)
97 printk(KERN_WARNING "Too much work in interrupt on uart401 (0x%X). UART jabbering ??\n", devc->base);
98 }
99
uart401intr(int irq,void * dev_id)100 irqreturn_t uart401intr(int irq, void *dev_id)
101 {
102 uart401_devc *devc = dev_id;
103
104 if (devc == NULL)
105 {
106 printk(KERN_ERR "uart401: bad devc\n");
107 return IRQ_NONE;
108 }
109
110 if (input_avail(devc))
111 uart401_input_loop(devc);
112 return IRQ_HANDLED;
113 }
114
115 static int
uart401_open(int dev,int mode,void (* input)(int dev,unsigned char data),void (* output)(int dev))116 uart401_open(int dev, int mode,
117 void (*input) (int dev, unsigned char data),
118 void (*output) (int dev)
119 )
120 {
121 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
122
123 if (devc->opened)
124 return -EBUSY;
125
126 /* Flush the UART */
127
128 while (input_avail(devc))
129 uart401_read(devc);
130
131 devc->midi_input_intr = input;
132 devc->opened = mode;
133 enter_uart_mode(devc);
134 devc->disabled = 0;
135
136 return 0;
137 }
138
uart401_close(int dev)139 static void uart401_close(int dev)
140 {
141 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
142
143 reset_uart401(devc);
144 devc->opened = 0;
145 }
146
uart401_out(int dev,unsigned char midi_byte)147 static int uart401_out(int dev, unsigned char midi_byte)
148 {
149 int timeout;
150 unsigned long flags;
151 uart401_devc *devc = (uart401_devc *) midi_devs[dev]->devc;
152
153 if (devc->disabled)
154 return 1;
155 /*
156 * Test for input since pending input seems to block the output.
157 */
158
159 spin_lock_irqsave(&devc->lock,flags);
160 if (input_avail(devc))
161 uart401_input_loop(devc);
162
163 spin_unlock_irqrestore(&devc->lock,flags);
164
165 /*
166 * Sometimes it takes about 13000 loops before the output becomes ready
167 * (After reset). Normally it takes just about 10 loops.
168 */
169
170 for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
171
172 if (!output_ready(devc))
173 {
174 printk(KERN_WARNING "uart401: Timeout - Device not responding\n");
175 devc->disabled = 1;
176 reset_uart401(devc);
177 enter_uart_mode(devc);
178 return 1;
179 }
180 uart401_write(devc, midi_byte);
181 return 1;
182 }
183
uart401_start_read(int dev)184 static inline int uart401_start_read(int dev)
185 {
186 return 0;
187 }
188
uart401_end_read(int dev)189 static inline int uart401_end_read(int dev)
190 {
191 return 0;
192 }
193
uart401_kick(int dev)194 static inline void uart401_kick(int dev)
195 {
196 }
197
uart401_buffer_status(int dev)198 static inline int uart401_buffer_status(int dev)
199 {
200 return 0;
201 }
202
203 #define MIDI_SYNTH_NAME "MPU-401 UART"
204 #define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT
205 #include "midi_synth.h"
206
207 static const struct midi_operations uart401_operations =
208 {
209 .owner = THIS_MODULE,
210 .info = {"MPU-401 (UART) MIDI", 0, 0, SNDCARD_MPU401},
211 .converter = &std_midi_synth,
212 .in_info = {0},
213 .open = uart401_open,
214 .close = uart401_close,
215 .outputc = uart401_out,
216 .start_read = uart401_start_read,
217 .end_read = uart401_end_read,
218 .kick = uart401_kick,
219 .buffer_status = uart401_buffer_status,
220 };
221
enter_uart_mode(uart401_devc * devc)222 static void enter_uart_mode(uart401_devc * devc)
223 {
224 int ok, timeout;
225 unsigned long flags;
226
227 spin_lock_irqsave(&devc->lock,flags);
228 for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
229
230 devc->input_byte = 0;
231 uart401_cmd(devc, UART_MODE_ON);
232
233 ok = 0;
234 for (timeout = 50000; timeout > 0 && !ok; timeout--)
235 if (devc->input_byte == MPU_ACK)
236 ok = 1;
237 else if (input_avail(devc))
238 if (uart401_read(devc) == MPU_ACK)
239 ok = 1;
240
241 spin_unlock_irqrestore(&devc->lock,flags);
242 }
243
reset_uart401(uart401_devc * devc)244 static int reset_uart401(uart401_devc * devc)
245 {
246 int ok, timeout, n;
247
248 /*
249 * Send the RESET command. Try again if no success at the first time.
250 */
251
252 ok = 0;
253
254 for (n = 0; n < 2 && !ok; n++)
255 {
256 for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);
257 devc->input_byte = 0;
258 uart401_cmd(devc, MPU_RESET);
259
260 /*
261 * Wait at least 25 msec. This method is not accurate so let's make the
262 * loop bit longer. Cannot sleep since this is called during boot.
263 */
264
265 for (timeout = 50000; timeout > 0 && !ok; timeout--)
266 {
267 if (devc->input_byte == MPU_ACK) /* Interrupt */
268 ok = 1;
269 else if (input_avail(devc))
270 {
271 if (uart401_read(devc) == MPU_ACK)
272 ok = 1;
273 }
274 }
275 }
276
277
278 if (ok)
279 {
280 DEB(printk("Reset UART401 OK\n"));
281 }
282 else
283 DDB(printk("Reset UART401 failed - No hardware detected.\n"));
284
285 if (ok)
286 uart401_input_loop(devc); /*
287 * Flush input before enabling interrupts
288 */
289
290 return ok;
291 }
292
probe_uart401(struct address_info * hw_config,struct module * owner)293 int probe_uart401(struct address_info *hw_config, struct module *owner)
294 {
295 uart401_devc *devc;
296 char *name = "MPU-401 (UART) MIDI";
297 int ok = 0;
298 unsigned long flags;
299
300 DDB(printk("Entered probe_uart401()\n"));
301
302 /* Default to "not found" */
303 hw_config->slots[4] = -1;
304
305 if (!request_region(hw_config->io_base, 4, "MPU-401 UART")) {
306 printk(KERN_INFO "uart401: could not request_region(%d, 4)\n", hw_config->io_base);
307 return 0;
308 }
309
310 devc = kmalloc(sizeof(uart401_devc), GFP_KERNEL);
311 if (!devc) {
312 printk(KERN_WARNING "uart401: Can't allocate memory\n");
313 goto cleanup_region;
314 }
315
316 devc->base = hw_config->io_base;
317 devc->irq = hw_config->irq;
318 devc->osp = hw_config->osp;
319 devc->midi_input_intr = NULL;
320 devc->opened = 0;
321 devc->input_byte = 0;
322 devc->my_dev = 0;
323 devc->share_irq = 0;
324 spin_lock_init(&devc->lock);
325
326 spin_lock_irqsave(&devc->lock,flags);
327 ok = reset_uart401(devc);
328 spin_unlock_irqrestore(&devc->lock,flags);
329
330 if (!ok)
331 goto cleanup_devc;
332
333 if (hw_config->name)
334 name = hw_config->name;
335
336 if (devc->irq < 0) {
337 devc->share_irq = 1;
338 devc->irq *= -1;
339 } else
340 devc->share_irq = 0;
341
342 if (!devc->share_irq)
343 if (request_irq(devc->irq, uart401intr, 0, "MPU-401 UART", devc) < 0) {
344 printk(KERN_WARNING "uart401: Failed to allocate IRQ%d\n", devc->irq);
345 devc->share_irq = 1;
346 }
347 devc->my_dev = sound_alloc_mididev();
348 enter_uart_mode(devc);
349
350 if (devc->my_dev == -1) {
351 printk(KERN_INFO "uart401: Too many midi devices detected\n");
352 goto cleanup_irq;
353 }
354 conf_printf(name, hw_config);
355 midi_devs[devc->my_dev] = kmemdup(&uart401_operations,
356 sizeof(struct midi_operations),
357 GFP_KERNEL);
358 if (!midi_devs[devc->my_dev]) {
359 printk(KERN_ERR "uart401: Failed to allocate memory\n");
360 goto cleanup_unload_mididev;
361 }
362
363 if (owner)
364 midi_devs[devc->my_dev]->owner = owner;
365
366 midi_devs[devc->my_dev]->devc = devc;
367 midi_devs[devc->my_dev]->converter = kmemdup(&std_midi_synth,
368 sizeof(struct synth_operations),
369 GFP_KERNEL);
370
371 if (!midi_devs[devc->my_dev]->converter) {
372 printk(KERN_WARNING "uart401: Failed to allocate memory\n");
373 goto cleanup_midi_devs;
374 }
375 strcpy(midi_devs[devc->my_dev]->info.name, name);
376 midi_devs[devc->my_dev]->converter->id = "UART401";
377 midi_devs[devc->my_dev]->converter->midi_dev = devc->my_dev;
378
379 if (owner)
380 midi_devs[devc->my_dev]->converter->owner = owner;
381
382 hw_config->slots[4] = devc->my_dev;
383 sequencer_init();
384 devc->opened = 0;
385 return 1;
386 cleanup_midi_devs:
387 kfree(midi_devs[devc->my_dev]);
388 cleanup_unload_mididev:
389 sound_unload_mididev(devc->my_dev);
390 cleanup_irq:
391 if (!devc->share_irq)
392 free_irq(devc->irq, devc);
393 cleanup_devc:
394 kfree(devc);
395 cleanup_region:
396 release_region(hw_config->io_base, 4);
397 return 0;
398 }
399
unload_uart401(struct address_info * hw_config)400 void unload_uart401(struct address_info *hw_config)
401 {
402 uart401_devc *devc;
403 int n=hw_config->slots[4];
404
405 /* Not set up */
406 if(n==-1 || midi_devs[n]==NULL)
407 return;
408
409 /* Not allocated (erm ??) */
410
411 devc = midi_devs[hw_config->slots[4]]->devc;
412 if (devc == NULL)
413 return;
414
415 reset_uart401(devc);
416 release_region(hw_config->io_base, 4);
417
418 if (!devc->share_irq)
419 free_irq(devc->irq, devc);
420 if (devc)
421 {
422 kfree(midi_devs[devc->my_dev]->converter);
423 kfree(midi_devs[devc->my_dev]);
424 kfree(devc);
425 devc = NULL;
426 }
427 /* This kills midi_devs[x] */
428 sound_unload_mididev(hw_config->slots[4]);
429 }
430
431 EXPORT_SYMBOL(probe_uart401);
432 EXPORT_SYMBOL(unload_uart401);
433 EXPORT_SYMBOL(uart401intr);
434
435 static struct address_info cfg_mpu;
436
437 static int io = -1;
438 static int irq = -1;
439
440 module_param(io, int, 0444);
441 module_param(irq, int, 0444);
442
443
init_uart401(void)444 static int __init init_uart401(void)
445 {
446 cfg_mpu.irq = irq;
447 cfg_mpu.io_base = io;
448
449 /* Can be loaded either for module use or to provide functions
450 to others */
451 if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1) {
452 printk(KERN_INFO "MPU-401 UART driver Copyright (C) Hannu Savolainen 1993-1997");
453 if (!probe_uart401(&cfg_mpu, THIS_MODULE))
454 return -ENODEV;
455 }
456
457 return 0;
458 }
459
cleanup_uart401(void)460 static void __exit cleanup_uart401(void)
461 {
462 if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1)
463 unload_uart401(&cfg_mpu);
464 }
465
466 module_init(init_uart401);
467 module_exit(cleanup_uart401);
468
469 #ifndef MODULE
setup_uart401(char * str)470 static int __init setup_uart401(char *str)
471 {
472 /* io, irq */
473 int ints[3];
474
475 str = get_options(str, ARRAY_SIZE(ints), ints);
476
477 io = ints[1];
478 irq = ints[2];
479
480 return 1;
481 }
482
483 __setup("uart401=", setup_uart401);
484 #endif
485 MODULE_LICENSE("GPL");
486