aboutsummaryrefslogtreecommitdiff
path: root/sound/oss/uart6850.c
blob: 501d3e654a67ba2e66849fad9cddb3945752bb50 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
/*
 * sound/oss/uart6850.c
 *
 *
 * Copyright (C) by Hannu Savolainen 1993-1997
 *
 * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
 * Version 2 (June 1991). See the "COPYING" file distributed with this software
 * for more info.
 * Extended by Alan Cox for Red Hat Software. Now a loadable MIDI driver.
 * 28/4/97 - (C) Copyright Alan Cox. Released under the GPL version 2.
 *
 * Alan Cox:		Updated for new modular code. Removed snd_* irq handling. Now
 *			uses native linux resources
 * Christoph Hellwig:	Adapted to module_init/module_exit
 * Jeff Garzik:		Made it work again, in theory
 *			FIXME: If the request_irq() succeeds, the probe succeeds. Ug.
 *
 *	Status: Testing required (no shit -jgarzik)
 *
 *
 */

#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/spinlock.h>
/* Mon Nov 22 22:38:35 MET 1993 marco@driq.home.usn.nl:
 *      added 6850 support, used with COVOX SoundMaster II and custom cards.
 */

#include "sound_config.h"

static int uart6850_base = 0x330;

static int *uart6850_osp;

#define	DATAPORT   (uart6850_base)
#define	COMDPORT   (uart6850_base+1)
#define	STATPORT   (uart6850_base+1)

static int uart6850_status(void)
{
	return inb(STATPORT);
}

#define input_avail()		(uart6850_status()&INPUT_AVAIL)
#define output_ready()		(uart6850_status()&OUTPUT_READY)

static void uart6850_cmd(unsigned char cmd)
{
	outb(cmd, COMDPORT);
}

static int uart6850_read(void)
{
	return inb(DATAPORT);
}

static void uart6850_write(unsigned char byte)
{
	outb(byte, DATAPORT);
}

#define	OUTPUT_READY	0x02	/* Mask for data ready Bit */
#define	INPUT_AVAIL	0x01	/* Mask for Data Send Ready Bit */

#define	UART_RESET	0x95
#define	UART_MODE_ON	0x03

static int uart6850_opened;
static int uart6850_irq;
static int uart6850_detected;
static int my_dev;
static DEFINE_SPINLOCK(lock);

static void (*midi_input_intr) (int dev, unsigned char data);
static void poll_uart6850(unsigned long dummy);


static DEFINE_TIMER(uart6850_timer, poll_uart6850, 0, 0);

static void uart6850_input_loop(void)
{
	int count = 10;

	while (count)
	{
		/*
		 * Not timed out
		 */
		if (input_avail())
		{
			unsigned char c = uart6850_read();
			count = 100;
			if (uart6850_opened & OPEN_READ)
				midi_input_intr(my_dev, c);
		}
		else
		{
			while (!input_avail() && count)
				count--;
		}
	}
}

static irqreturn_t m6850intr(int irq, void *dev_id, struct pt_regs *dummy)
{
	if (input_avail())
		uart6850_input_loop();
	return IRQ_HANDLED;
}

/*
 *	It looks like there is no input interrupts in the UART mode. Let's try
 *	polling.
 */

static void poll_uart6850(unsigned long dummy)
{
	unsigned long flags;

	if (!(uart6850_opened & OPEN_READ))
		return;		/* Device has been closed */

	spin_lock_irqsave(&lock,flags);
	if (input_avail())
		uart6850_input_loop();

	uart6850_timer.expires = 1 + jiffies;
	add_timer(&uart6850_timer);
	
	/*
	 *	Come back later
	 */

	spin_unlock_irqrestore(&lock,flags);
}

static int uart6850_open(int dev, int mode,
	      void            (*input) (int dev, unsigned char data),
	      void            (*output) (int dev)
)
{
	if (uart6850_opened)
	{
/*		  printk("Midi6850: Midi busy\n");*/
		  return -EBUSY;
	};

	uart6850_cmd(UART_RESET);
	uart6850_input_loop();
	midi_input_intr = input;
	uart6850_opened = mode;
	poll_uart6850(0);	/*
				 * Enable input polling
				 */

	return 0;
}

static void uart6850_close(int dev)
{
	uart6850_cmd(UART_MODE_ON);
	del_timer(&uart6850_timer);
	uart6850_opened = 0;
}

static int uart6850_out(int dev, unsigned char midi_byte)
{
	int timeout;
	unsigned long flags;

	/*
	 * Test for input since pending input seems to block the output.
	 */

	spin_lock_irqsave(&lock,flags);

	if (input_avail())
		uart6850_input_loop();

	spin_unlock_irqrestore(&lock,flags);

	/*
	 * Sometimes it takes about 13000 loops before the output becomes ready
	 * (After reset). Normally it takes just about 10 loops.
	 */

	for (timeout = 30000; timeout > 0 && !output_ready(); timeout--);	/*
										 * Wait
										 */
	if (!output_ready())
	{
		printk(KERN_WARNING "Midi6850: Timeout\n");
		return 0;
	}
	uart6850_write(midi_byte);
	return 1;
}

static inline int uart6850_command(int dev, unsigned char *midi_byte)
{
	return 1;
}

static inline int uart6850_start_read(int dev)
{
	return 0;
}

static inline int uart6850_end_read(int dev)
{
	return 0;
}

static inline void uart6850_kick(int dev)
{
}

static inline int uart6850_buffer_status(int dev)
{
	return 0;		/*
				 * No data in buffers
				 */
}

#define MIDI_SYNTH_NAME	"6850 UART Midi"
#define MIDI_SYNTH_CAPS	SYNTH_CAP_INPUT
#include "midi_synth.h"

static struct midi_operations uart6850_operations =
{
	.owner		= THIS_MODULE,
	.info		= {"6850 UART", 0, 0, SNDCARD_UART6850},
	.converter	= &std_midi_synth,
	.in_info	= {0},
	.open		= uart6850_open,
	.close		= uart6850_close,
	.outputc	= uart6850_out,
	.start_read	= uart6850_start_read,
	.end_read	= uart6850_end_read,
	.kick		= uart6850_kick,
	.command	= uart6850_command,
	.buffer_status	= uart6850_buffer_status
};


static void __init attach_uart6850(struct address_info *hw_config)
{
	int ok, timeout;
	unsigned long   flags;

	if (!uart6850_detected)
		return;

	if ((my_dev = sound_alloc_mididev()) == -1)
	{
		printk(KERN_INFO "uart6850: Too many midi devices detected\n");
		return;
	}
	uart6850_base = hw_config->io_base;
	uart6850_osp = hw_config->osp;
	uart6850_irq = hw_config->irq;

	spin_lock_irqsave(&lock,flags);

	for (timeout = 30000; timeout > 0 && !output_ready(); timeout--);	/*
										 * Wait
										 */
	uart6850_cmd(UART_MODE_ON);
	ok = 1;
	spin_unlock_irqrestore(&lock,flags);

	conf_printf("6850 Midi Interface", hw_config);

	std_midi_synth.midi_dev = my_dev;
	hw_config->slots[4] = my_dev;
	midi_devs[my_dev] = &uart6850_operations;
	sequencer_init();
}

static inline int reset_uart6850(void)
{
	uart6850_read();
	return 1;		/*
				 * OK
				 */
}

static int __init probe_uart6850(struct address_info *hw_config)
{
	int ok;

	uart6850_osp = hw_config->osp;
	uart6850_base = hw_config->io_base;
	uart6850_irq = hw_config->irq;

	if (request_irq(uart6850_irq, m6850intr, 0, "MIDI6850", NULL) < 0)
		return 0;

	ok = reset_uart6850();
	uart6850_detected = ok;
	return ok;
}

static void __exit unload_uart6850(struct address_info *hw_config)
{
	free_irq(hw_config->irq, NULL);
	sound_unload_mididev(hw_config->slots[4]);
}

static struct address_info cfg_mpu;

static int __initdata io = -1;
static int __initdata irq = -1;

module_param(io, int, 0);
module_param(irq, int, 0);

static int __init init_uart6850(void)
{
	cfg_mpu.io_base = io;
	cfg_mpu.irq = irq;

	if (cfg_mpu.io_base == -1 || cfg_mpu.irq == -1) {
		printk(KERN_INFO "uart6850: irq and io must be set.\n");
		return -EINVAL;
	}

	if (probe_uart6850(&cfg_mpu))
		return -ENODEV;
	attach_uart6850(&cfg_mpu);

	return 0;
}

static void __exit cleanup_uart6850(void)
{
	unload_uart6850(&cfg_mpu);
}

module_init(init_uart6850);
module_exit(cleanup_uart6850);

#ifndef MODULE
static int __init setup_uart6850(char *str)
{
	/* io, irq */
	int ints[3];
	
	str = get_options(str, ARRAY_SIZE(ints), ints);
	
	io = ints[1];
	irq = ints[2];

	return 1;
}
__setup("uart6850=", setup_uart6850);
#endif
MODULE_LICENSE("GPL");