1 /*
2 * sound/oss/uart6850.c
3 *
4 *
5 * Copyright (C) by Hannu Savolainen 1993-1997
6 *
7 * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
8 * Version 2 (June 1991). See the "COPYING" file distributed with this software
9 * for more info.
10 * Extended by Alan Cox for Red Hat Software. Now a loadable MIDI driver.
11 * 28/4/97 - (C) Copyright Alan Cox. Released under the GPL version 2.
12 *
13 * Alan Cox: Updated for new modular code. Removed snd_* irq handling. Now
14 * uses native linux resources
15 * Christoph Hellwig: Adapted to module_init/module_exit
16 * Jeff Garzik: Made it work again, in theory
17 * FIXME: If the request_irq() succeeds, the probe succeeds. Ug.
18 *
19 * Status: Testing required (no shit -jgarzik)
20 *
21 *
22 */
23
24 #include <linux/init.h>
25 #include <linux/interrupt.h>
26 #include <linux/module.h>
27 #include <linux/spinlock.h>
28 /* Mon Nov 22 22:38:35 MET 1993 marco@driq.home.usn.nl:
29 * added 6850 support, used with COVOX SoundMaster II and custom cards.
30 */
31
32 #include "sound_config.h"
33
34 static int uart6850_base = 0x330;
35
36 static int *uart6850_osp;
37
38 #define DATAPORT (uart6850_base)
39 #define COMDPORT (uart6850_base+1)
40 #define STATPORT (uart6850_base+1)
41
uart6850_status(void)42 static int uart6850_status(void)
43 {
44 return inb(STATPORT);
45 }
46
47 #define input_avail() (uart6850_status()&INPUT_AVAIL)
48 #define output_ready() (uart6850_status()&OUTPUT_READY)
49
uart6850_cmd(unsigned char cmd)50 static void uart6850_cmd(unsigned char cmd)
51 {
52 outb(cmd, COMDPORT);
53 }
54
uart6850_read(void)55 static int uart6850_read(void)
56 {
57 return inb(DATAPORT);
58 }
59
uart6850_write(unsigned char byte)60 static void uart6850_write(unsigned char byte)
61 {
62 outb(byte, DATAPORT);
63 }
64
65 #define OUTPUT_READY 0x02 /* Mask for data ready Bit */
66 #define INPUT_AVAIL 0x01 /* Mask for Data Send Ready Bit */
67
68 #define UART_RESET 0x95
69 #define UART_MODE_ON 0x03
70
71 static int uart6850_opened;
72 static int uart6850_irq;
73 static int uart6850_detected;
74 static int my_dev;
75 static DEFINE_SPINLOCK(lock);
76
77 static void (*midi_input_intr) (int dev, unsigned char data);
78 static void poll_uart6850(unsigned long dummy);
79
80
81 static DEFINE_TIMER(uart6850_timer, poll_uart6850, 0, 0);
82
uart6850_input_loop(void)83 static void uart6850_input_loop(void)
84 {
85 int count = 10;
86
87 while (count)
88 {
89 /*
90 * Not timed out
91 */
92 if (input_avail())
93 {
94 unsigned char c = uart6850_read();
95 count = 100;
96 if (uart6850_opened & OPEN_READ)
97 midi_input_intr(my_dev, c);
98 }
99 else
100 {
101 while (!input_avail() && count)
102 count--;
103 }
104 }
105 }
106
m6850intr(int irq,void * dev_id)107 static irqreturn_t m6850intr(int irq, void *dev_id)
108 {
109 if (input_avail())
110 uart6850_input_loop();
111 return IRQ_HANDLED;
112 }
113
114 /*
115 * It looks like there is no input interrupts in the UART mode. Let's try
116 * polling.
117 */
118
poll_uart6850(unsigned long dummy)119 static void poll_uart6850(unsigned long dummy)
120 {
121 unsigned long flags;
122
123 if (!(uart6850_opened & OPEN_READ))
124 return; /* Device has been closed */
125
126 spin_lock_irqsave(&lock,flags);
127 if (input_avail())
128 uart6850_input_loop();
129
130 uart6850_timer.expires = 1 + jiffies;
131 add_timer(&uart6850_timer);
132
133 /*
134 * Come back later
135 */
136
137 spin_unlock_irqrestore(&lock,flags);
138 }
139
uart6850_open(int dev,int mode,void (* input)(int dev,unsigned char data),void (* output)(int dev))140 static int uart6850_open(int dev, int mode,
141 void (*input) (int dev, unsigned char data),
142 void (*output) (int dev)
143 )
144 {
145 if (uart6850_opened)
146 {
147 /* printk("Midi6850: Midi busy\n");*/
148 return -EBUSY;
149 };
150
151 uart6850_cmd(UART_RESET);
152 uart6850_input_loop();
153 midi_input_intr = input;
154 uart6850_opened = mode;
155 poll_uart6850(0); /*
156 * Enable input polling
157 */
158
159 return 0;
160 }
161
uart6850_close(int dev)162 static void uart6850_close(int dev)
163 {
164 uart6850_cmd(UART_MODE_ON);
165 del_timer(&uart6850_timer);
166 uart6850_opened = 0;
167 }
168
uart6850_out(int dev,unsigned char midi_byte)169 static int uart6850_out(int dev, unsigned char midi_byte)
170 {
171 int timeout;
172 unsigned long flags;
173
174 /*
175 * Test for input since pending input seems to block the output.
176 */
177
178 spin_lock_irqsave(&lock,flags);
179
180 if (input_avail())
181 uart6850_input_loop();
182
183 spin_unlock_irqrestore(&lock,flags);
184
185 /*
186 * Sometimes it takes about 13000 loops before the output becomes ready
187 * (After reset). Normally it takes just about 10 loops.
188 */
189
190 for (timeout = 30000; timeout > 0 && !output_ready(); timeout--); /*
191 * Wait
192 */
193 if (!output_ready())
194 {
195 printk(KERN_WARNING "Midi6850: Timeout\n");
196 return 0;
197 }
198 uart6850_write(midi_byte);
199 return 1;
200 }
201
uart6850_command(int dev,unsigned char * midi_byte)202 static inline int uart6850_command(int dev, unsigned char *midi_byte)
203 {
204 return 1;
205 }
206
uart6850_start_read(int dev)207 static inline int uart6850_start_read(int dev)
208 {
209 return 0;
210 }
211
uart6850_end_read(int dev)212 static inline int uart6850_end_read(int dev)
213 {
214 return 0;
215 }
216
uart6850_kick(int dev)217 static inline void uart6850_kick(int dev)
218 {
219 }
220
uart6850_buffer_status(int dev)221 static inline int uart6850_buffer_status(int dev)
222 {
223 return 0; /*
224 * No data in buffers
225 */
226 }
227
228 #define MIDI_SYNTH_NAME "6850 UART Midi"
229 #define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT
230 #include "midi_synth.h"
231
232 static struct midi_operations uart6850_operations =
233 {
234 .owner = THIS_MODULE,
235 .info = {"6850 UART", 0, 0, SNDCARD_UART6850},
236 .converter = &std_midi_synth,
237 .in_info = {0},
238 .open = uart6850_open,
239 .close = uart6850_close,
240 .outputc = uart6850_out,
241 .start_read = uart6850_start_read,
242 .end_read = uart6850_end_read,
243 .kick = uart6850_kick,
244 .command = uart6850_command,
245 .buffer_status = uart6850_buffer_status
246 };
247
248
attach_uart6850(struct address_info * hw_config)249 static void __init attach_uart6850(struct address_info *hw_config)
250 {
251 int ok, timeout;
252 unsigned long flags;
253
254 if (!uart6850_detected)
255 return;
256
257 if ((my_dev = sound_alloc_mididev()) == -1)
258 {
259 printk(KERN_INFO "uart6850: Too many midi devices detected\n");
260 return;
261 }
262 uart6850_base = hw_config->io_base;
263 uart6850_osp = hw_config->osp;
264 uart6850_irq = hw_config->irq;
265
266 spin_lock_irqsave(&lock,flags);
267
268 for (timeout = 30000; timeout > 0 && !output_ready(); timeout--); /*
269 * Wait
270 */
271 uart6850_cmd(UART_MODE_ON);
272 ok = 1;
273 spin_unlock_irqrestore(&lock,flags);
274
275 conf_printf("6850 Midi Interface", hw_config);
276
277 std_midi_synth.midi_dev = my_dev;
278 hw_config->slots[4] = my_dev;
279 midi_devs[my_dev] = &uart6850_operations;
280 sequencer_init();
281 }
282
reset_uart6850(void)283 static inline int reset_uart6850(void)
284 {
285 uart6850_read();
286 return 1; /*
287 * OK
288 */
289 }
290
probe_uart6850(struct address_info * hw_config)291 static int __init probe_uart6850(struct address_info *hw_config)
292 {
293 int ok;
294
295 uart6850_osp = hw_config->osp;
296 uart6850_base = hw_config->io_base;
297 uart6850_irq = hw_config->irq;
298
299 if (request_irq(uart6850_irq, m6850intr, 0, "MIDI6850", NULL) < 0)
300 return 0;
301
302 ok = reset_uart6850();
303 uart6850_detected = ok;
304 return ok;
305 }
306
unload_uart6850(struct address_info * hw_config)307 static void __exit unload_uart6850(struct address_info *hw_config)
308 {
309 free_irq(hw_config->irq, NULL);
310 sound_unload_mididev(hw_config->slots[4]);
311 }
312
313 static struct address_info cfg_mpu;
314
315 static int __initdata io = -1;
316 static int __initdata irq = -1;
317
318 module_param(io, int, 0);
319 module_param(irq, int, 0);
320
init_uart6850(void)321 static int __init init_uart6850(void)
322 {
323 cfg_mpu.io_base = io;
324 cfg_mpu.irq = irq;
325
326 if (cfg_mpu.io_base == -1 || cfg_mpu.irq == -1) {
327 printk(KERN_INFO "uart6850: irq and io must be set.\n");
328 return -EINVAL;
329 }
330
331 if (probe_uart6850(&cfg_mpu))
332 return -ENODEV;
333 attach_uart6850(&cfg_mpu);
334
335 return 0;
336 }
337
cleanup_uart6850(void)338 static void __exit cleanup_uart6850(void)
339 {
340 unload_uart6850(&cfg_mpu);
341 }
342
343 module_init(init_uart6850);
344 module_exit(cleanup_uart6850);
345
346 #ifndef MODULE
setup_uart6850(char * str)347 static int __init setup_uart6850(char *str)
348 {
349 /* io, irq */
350 int ints[3];
351
352 str = get_options(str, ARRAY_SIZE(ints), ints);
353
354 io = ints[1];
355 irq = ints[2];
356
357 return 1;
358 }
359 __setup("uart6850=", setup_uart6850);
360 #endif
361 MODULE_LICENSE("GPL");
362