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
31typedef 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}
42uart401_devc;
43
44#define	DATAPORT   (devc->base)
45#define	COMDPORT   (devc->base+1)
46#define	STATPORT   (devc->base+1)
47
48static 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
56static void uart401_cmd(uart401_devc * devc, unsigned char cmd)
57{
58	outb((cmd), COMDPORT);
59}
60
61static int uart401_read(uart401_devc * devc)
62{
63	return inb(DATAPORT);
64}
65
66static 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
77static int      reset_uart401(uart401_devc * devc);
78static void     enter_uart_mode(uart401_devc * devc);
79
80static 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
97void 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
111static int
112uart401_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
135static 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
143static 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
182static inline int uart401_start_read(int dev)
183{
184	return 0;
185}
186
187static inline int uart401_end_read(int dev)
188{
189	return 0;
190}
191
192static inline void uart401_kick(int dev)
193{
194}
195
196static 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
205static const 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
220static 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
243static 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
292int 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	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;
382cleanup_midi_devs:
383	kfree(midi_devs[devc->my_dev]);
384cleanup_unload_mididev:
385	sound_unload_mididev(devc->my_dev);
386cleanup_irq:
387	if (!devc->share_irq)
388		free_irq(devc->irq, devc);
389cleanup_devc:
390	kfree(devc);
391cleanup_region:
392	release_region(hw_config->io_base, 4);
393	return 0;
394}
395
396void 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
427EXPORT_SYMBOL(probe_uart401);
428EXPORT_SYMBOL(unload_uart401);
429EXPORT_SYMBOL(uart401intr);
430
431static struct address_info cfg_mpu;
432
433static int __initdata io = -1;
434static int __initdata irq = -1;
435
436MODULE_PARM(io, "i");
437MODULE_PARM(irq, "i");
438
439
440static 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
456static void __exit cleanup_uart401(void)
457{
458	if (cfg_mpu.io_base != -1 && cfg_mpu.irq != -1)
459		unload_uart401(&cfg_mpu);
460}
461
462module_init(init_uart401);
463module_exit(cleanup_uart401);
464
465#ifndef MODULE
466static 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
481MODULE_LICENSE("GPL");
482