xref: /openbmc/linux/sound/isa/sb/sb8_main.c (revision 275876e2)
1 /*
2  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
3  *                   Uros Bizjak <uros@kss-loka.si>
4  *
5  *  Routines for control of 8-bit SoundBlaster cards and clones
6  *  Please note: I don't have access to old SB8 soundcards.
7  *
8  *
9  *   This program is free software; you can redistribute it and/or modify
10  *   it under the terms of the GNU General Public License as published by
11  *   the Free Software Foundation; either version 2 of the License, or
12  *   (at your option) any later version.
13  *
14  *   This program is distributed in the hope that it will be useful,
15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  *   GNU General Public License for more details.
18  *
19  *   You should have received a copy of the GNU General Public License
20  *   along with this program; if not, write to the Free Software
21  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
22  *
23  * --
24  *
25  * Thu Apr 29 20:36:17 BST 1999 George David Morrison <gdm@gedamo.demon.co.uk>
26  *   DSP can't respond to commands whilst in "high speed" mode. Caused
27  *   glitching during playback. Fixed.
28  *
29  * Wed Jul 12 22:02:55 CEST 2000 Uros Bizjak <uros@kss-loka.si>
30  *   Cleaned up and rewrote lowlevel routines.
31  */
32 
33 #include <asm/io.h>
34 #include <asm/dma.h>
35 #include <linux/init.h>
36 #include <linux/time.h>
37 #include <linux/module.h>
38 #include <sound/core.h>
39 #include <sound/sb.h>
40 
41 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Uros Bizjak <uros@kss-loka.si>");
42 MODULE_DESCRIPTION("Routines for control of 8-bit SoundBlaster cards and clones");
43 MODULE_LICENSE("GPL");
44 
45 #define SB8_CLOCK	1000000
46 #define SB8_DEN(v)	((SB8_CLOCK + (v) / 2) / (v))
47 #define SB8_RATE(v)	(SB8_CLOCK / SB8_DEN(v))
48 
49 static struct snd_ratnum clock = {
50 	.num = SB8_CLOCK,
51 	.den_min = 1,
52 	.den_max = 256,
53 	.den_step = 1,
54 };
55 
56 static struct snd_pcm_hw_constraint_ratnums hw_constraints_clock = {
57 	.nrats = 1,
58 	.rats = &clock,
59 };
60 
61 static struct snd_ratnum stereo_clocks[] = {
62 	{
63 		.num = SB8_CLOCK,
64 		.den_min = SB8_DEN(22050),
65 		.den_max = SB8_DEN(22050),
66 		.den_step = 1,
67 	},
68 	{
69 		.num = SB8_CLOCK,
70 		.den_min = SB8_DEN(11025),
71 		.den_max = SB8_DEN(11025),
72 		.den_step = 1,
73 	}
74 };
75 
76 static int snd_sb8_hw_constraint_rate_channels(struct snd_pcm_hw_params *params,
77 					       struct snd_pcm_hw_rule *rule)
78 {
79 	struct snd_interval *c = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
80 	if (c->min > 1) {
81 	  	unsigned int num = 0, den = 0;
82 		int err = snd_interval_ratnum(hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE),
83 					  2, stereo_clocks, &num, &den);
84 		if (err >= 0 && den) {
85 			params->rate_num = num;
86 			params->rate_den = den;
87 		}
88 		return err;
89 	}
90 	return 0;
91 }
92 
93 static int snd_sb8_hw_constraint_channels_rate(struct snd_pcm_hw_params *params,
94 					       struct snd_pcm_hw_rule *rule)
95 {
96 	struct snd_interval *r = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
97 	if (r->min > SB8_RATE(22050) || r->max <= SB8_RATE(11025)) {
98 		struct snd_interval t = { .min = 1, .max = 1 };
99 		return snd_interval_refine(hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS), &t);
100 	}
101 	return 0;
102 }
103 
104 static int snd_sb8_playback_prepare(struct snd_pcm_substream *substream)
105 {
106 	unsigned long flags;
107 	struct snd_sb *chip = snd_pcm_substream_chip(substream);
108 	struct snd_pcm_runtime *runtime = substream->runtime;
109 	unsigned int mixreg, rate, size, count;
110 	unsigned char format;
111 	unsigned char stereo = runtime->channels > 1;
112 	int dma;
113 
114 	rate = runtime->rate;
115 	switch (chip->hardware) {
116 	case SB_HW_JAZZ16:
117 		if (runtime->format == SNDRV_PCM_FORMAT_S16_LE) {
118 			if (chip->mode & SB_MODE_CAPTURE_16)
119 				return -EBUSY;
120 			else
121 				chip->mode |= SB_MODE_PLAYBACK_16;
122 		}
123 		chip->playback_format = SB_DSP_LO_OUTPUT_AUTO;
124 		break;
125 	case SB_HW_PRO:
126 		if (runtime->channels > 1) {
127 			if (snd_BUG_ON(rate != SB8_RATE(11025) &&
128 				       rate != SB8_RATE(22050)))
129 				return -EINVAL;
130 			chip->playback_format = SB_DSP_HI_OUTPUT_AUTO;
131 			break;
132 		}
133 		/* fallthru */
134 	case SB_HW_201:
135 		if (rate > 23000) {
136 			chip->playback_format = SB_DSP_HI_OUTPUT_AUTO;
137 			break;
138 		}
139 		/* fallthru */
140 	case SB_HW_20:
141 		chip->playback_format = SB_DSP_LO_OUTPUT_AUTO;
142 		break;
143 	case SB_HW_10:
144 		chip->playback_format = SB_DSP_OUTPUT;
145 		break;
146 	default:
147 		return -EINVAL;
148 	}
149 	if (chip->mode & SB_MODE_PLAYBACK_16) {
150 		format = stereo ? SB_DSP_STEREO_16BIT : SB_DSP_MONO_16BIT;
151 		dma = chip->dma16;
152 	} else {
153 		format = stereo ? SB_DSP_STEREO_8BIT : SB_DSP_MONO_8BIT;
154 		chip->mode |= SB_MODE_PLAYBACK_8;
155 		dma = chip->dma8;
156 	}
157 	size = chip->p_dma_size = snd_pcm_lib_buffer_bytes(substream);
158 	count = chip->p_period_size = snd_pcm_lib_period_bytes(substream);
159 	spin_lock_irqsave(&chip->reg_lock, flags);
160 	snd_sbdsp_command(chip, SB_DSP_SPEAKER_ON);
161 	if (chip->hardware == SB_HW_JAZZ16)
162 		snd_sbdsp_command(chip, format);
163 	else if (stereo) {
164 		/* set playback stereo mode */
165 		spin_lock(&chip->mixer_lock);
166 		mixreg = snd_sbmixer_read(chip, SB_DSP_STEREO_SW);
167 		snd_sbmixer_write(chip, SB_DSP_STEREO_SW, mixreg | 0x02);
168 		spin_unlock(&chip->mixer_lock);
169 
170 		/* Soundblaster hardware programming reference guide, 3-23 */
171 		snd_sbdsp_command(chip, SB_DSP_DMA8_EXIT);
172 		runtime->dma_area[0] = 0x80;
173 		snd_dma_program(dma, runtime->dma_addr, 1, DMA_MODE_WRITE);
174 		/* force interrupt */
175 		snd_sbdsp_command(chip, SB_DSP_OUTPUT);
176 		snd_sbdsp_command(chip, 0);
177 		snd_sbdsp_command(chip, 0);
178 	}
179 	snd_sbdsp_command(chip, SB_DSP_SAMPLE_RATE);
180 	if (stereo) {
181 		snd_sbdsp_command(chip, 256 - runtime->rate_den / 2);
182 		spin_lock(&chip->mixer_lock);
183 		/* save output filter status and turn it off */
184 		mixreg = snd_sbmixer_read(chip, SB_DSP_PLAYBACK_FILT);
185 		snd_sbmixer_write(chip, SB_DSP_PLAYBACK_FILT, mixreg | 0x20);
186 		spin_unlock(&chip->mixer_lock);
187 		/* just use force_mode16 for temporary storate... */
188 		chip->force_mode16 = mixreg;
189 	} else {
190 		snd_sbdsp_command(chip, 256 - runtime->rate_den);
191 	}
192 	if (chip->playback_format != SB_DSP_OUTPUT) {
193 		if (chip->mode & SB_MODE_PLAYBACK_16)
194 			count /= 2;
195 		count--;
196 		snd_sbdsp_command(chip, SB_DSP_BLOCK_SIZE);
197 		snd_sbdsp_command(chip, count & 0xff);
198 		snd_sbdsp_command(chip, count >> 8);
199 	}
200 	spin_unlock_irqrestore(&chip->reg_lock, flags);
201 	snd_dma_program(dma, runtime->dma_addr,
202 			size, DMA_MODE_WRITE | DMA_AUTOINIT);
203 	return 0;
204 }
205 
206 static int snd_sb8_playback_trigger(struct snd_pcm_substream *substream,
207 				    int cmd)
208 {
209 	unsigned long flags;
210 	struct snd_sb *chip = snd_pcm_substream_chip(substream);
211 	unsigned int count;
212 
213 	spin_lock_irqsave(&chip->reg_lock, flags);
214 	switch (cmd) {
215 	case SNDRV_PCM_TRIGGER_START:
216 		snd_sbdsp_command(chip, chip->playback_format);
217 		if (chip->playback_format == SB_DSP_OUTPUT) {
218 			count = chip->p_period_size - 1;
219 			snd_sbdsp_command(chip, count & 0xff);
220 			snd_sbdsp_command(chip, count >> 8);
221 		}
222 		break;
223 	case SNDRV_PCM_TRIGGER_STOP:
224 		if (chip->playback_format == SB_DSP_HI_OUTPUT_AUTO) {
225 			struct snd_pcm_runtime *runtime = substream->runtime;
226 			snd_sbdsp_reset(chip);
227 			if (runtime->channels > 1) {
228 				spin_lock(&chip->mixer_lock);
229 				/* restore output filter and set hardware to mono mode */
230 				snd_sbmixer_write(chip, SB_DSP_STEREO_SW, chip->force_mode16 & ~0x02);
231 				spin_unlock(&chip->mixer_lock);
232 			}
233 		} else {
234 			snd_sbdsp_command(chip, SB_DSP_DMA8_OFF);
235 		}
236 		snd_sbdsp_command(chip, SB_DSP_SPEAKER_OFF);
237 	}
238 	spin_unlock_irqrestore(&chip->reg_lock, flags);
239 	return 0;
240 }
241 
242 static int snd_sb8_hw_params(struct snd_pcm_substream *substream,
243 			     struct snd_pcm_hw_params *hw_params)
244 {
245 	return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params));
246 }
247 
248 static int snd_sb8_hw_free(struct snd_pcm_substream *substream)
249 {
250 	snd_pcm_lib_free_pages(substream);
251 	return 0;
252 }
253 
254 static int snd_sb8_capture_prepare(struct snd_pcm_substream *substream)
255 {
256 	unsigned long flags;
257 	struct snd_sb *chip = snd_pcm_substream_chip(substream);
258 	struct snd_pcm_runtime *runtime = substream->runtime;
259 	unsigned int mixreg, rate, size, count;
260 	unsigned char format;
261 	unsigned char stereo = runtime->channels > 1;
262 	int dma;
263 
264 	rate = runtime->rate;
265 	switch (chip->hardware) {
266 	case SB_HW_JAZZ16:
267 		if (runtime->format == SNDRV_PCM_FORMAT_S16_LE) {
268 			if (chip->mode & SB_MODE_PLAYBACK_16)
269 				return -EBUSY;
270 			else
271 				chip->mode |= SB_MODE_CAPTURE_16;
272 		}
273 		chip->capture_format = SB_DSP_LO_INPUT_AUTO;
274 		break;
275 	case SB_HW_PRO:
276 		if (runtime->channels > 1) {
277 			if (snd_BUG_ON(rate != SB8_RATE(11025) &&
278 				       rate != SB8_RATE(22050)))
279 				return -EINVAL;
280 			chip->capture_format = SB_DSP_HI_INPUT_AUTO;
281 			break;
282 		}
283 		chip->capture_format = (rate > 23000) ? SB_DSP_HI_INPUT_AUTO : SB_DSP_LO_INPUT_AUTO;
284 		break;
285 	case SB_HW_201:
286 		if (rate > 13000) {
287 			chip->capture_format = SB_DSP_HI_INPUT_AUTO;
288 			break;
289 		}
290 		/* fallthru */
291 	case SB_HW_20:
292 		chip->capture_format = SB_DSP_LO_INPUT_AUTO;
293 		break;
294 	case SB_HW_10:
295 		chip->capture_format = SB_DSP_INPUT;
296 		break;
297 	default:
298 		return -EINVAL;
299 	}
300 	if (chip->mode & SB_MODE_CAPTURE_16) {
301 		format = stereo ? SB_DSP_STEREO_16BIT : SB_DSP_MONO_16BIT;
302 		dma = chip->dma16;
303 	} else {
304 		format = stereo ? SB_DSP_STEREO_8BIT : SB_DSP_MONO_8BIT;
305 		chip->mode |= SB_MODE_CAPTURE_8;
306 		dma = chip->dma8;
307 	}
308 	size = chip->c_dma_size = snd_pcm_lib_buffer_bytes(substream);
309 	count = chip->c_period_size = snd_pcm_lib_period_bytes(substream);
310 	spin_lock_irqsave(&chip->reg_lock, flags);
311 	snd_sbdsp_command(chip, SB_DSP_SPEAKER_OFF);
312 	if (chip->hardware == SB_HW_JAZZ16)
313 		snd_sbdsp_command(chip, format);
314 	else if (stereo)
315 		snd_sbdsp_command(chip, SB_DSP_STEREO_8BIT);
316 	snd_sbdsp_command(chip, SB_DSP_SAMPLE_RATE);
317 	if (stereo) {
318 		snd_sbdsp_command(chip, 256 - runtime->rate_den / 2);
319 		spin_lock(&chip->mixer_lock);
320 		/* save input filter status and turn it off */
321 		mixreg = snd_sbmixer_read(chip, SB_DSP_CAPTURE_FILT);
322 		snd_sbmixer_write(chip, SB_DSP_CAPTURE_FILT, mixreg | 0x20);
323 		spin_unlock(&chip->mixer_lock);
324 		/* just use force_mode16 for temporary storate... */
325 		chip->force_mode16 = mixreg;
326 	} else {
327 		snd_sbdsp_command(chip, 256 - runtime->rate_den);
328 	}
329 	if (chip->capture_format != SB_DSP_INPUT) {
330 		if (chip->mode & SB_MODE_PLAYBACK_16)
331 			count /= 2;
332 		count--;
333 		snd_sbdsp_command(chip, SB_DSP_BLOCK_SIZE);
334 		snd_sbdsp_command(chip, count & 0xff);
335 		snd_sbdsp_command(chip, count >> 8);
336 	}
337 	spin_unlock_irqrestore(&chip->reg_lock, flags);
338 	snd_dma_program(dma, runtime->dma_addr,
339 			size, DMA_MODE_READ | DMA_AUTOINIT);
340 	return 0;
341 }
342 
343 static int snd_sb8_capture_trigger(struct snd_pcm_substream *substream,
344 				   int cmd)
345 {
346 	unsigned long flags;
347 	struct snd_sb *chip = snd_pcm_substream_chip(substream);
348 	unsigned int count;
349 
350 	spin_lock_irqsave(&chip->reg_lock, flags);
351 	switch (cmd) {
352 	case SNDRV_PCM_TRIGGER_START:
353 		snd_sbdsp_command(chip, chip->capture_format);
354 		if (chip->capture_format == SB_DSP_INPUT) {
355 			count = chip->c_period_size - 1;
356 			snd_sbdsp_command(chip, count & 0xff);
357 			snd_sbdsp_command(chip, count >> 8);
358 		}
359 		break;
360 	case SNDRV_PCM_TRIGGER_STOP:
361 		if (chip->capture_format == SB_DSP_HI_INPUT_AUTO) {
362 			struct snd_pcm_runtime *runtime = substream->runtime;
363 			snd_sbdsp_reset(chip);
364 			if (runtime->channels > 1) {
365 				/* restore input filter status */
366 				spin_lock(&chip->mixer_lock);
367 				snd_sbmixer_write(chip, SB_DSP_CAPTURE_FILT, chip->force_mode16);
368 				spin_unlock(&chip->mixer_lock);
369 				/* set hardware to mono mode */
370 				snd_sbdsp_command(chip, SB_DSP_MONO_8BIT);
371 			}
372 		} else {
373 			snd_sbdsp_command(chip, SB_DSP_DMA8_OFF);
374 		}
375 		snd_sbdsp_command(chip, SB_DSP_SPEAKER_OFF);
376 	}
377 	spin_unlock_irqrestore(&chip->reg_lock, flags);
378 	return 0;
379 }
380 
381 irqreturn_t snd_sb8dsp_interrupt(struct snd_sb *chip)
382 {
383 	struct snd_pcm_substream *substream;
384 	struct snd_pcm_runtime *runtime;
385 
386 	snd_sb_ack_8bit(chip);
387 	switch (chip->mode) {
388 	case SB_MODE_PLAYBACK_16:	/* ok.. playback is active */
389 		if (chip->hardware != SB_HW_JAZZ16)
390 			break;
391 		/* fallthru */
392 	case SB_MODE_PLAYBACK_8:
393 		substream = chip->playback_substream;
394 		runtime = substream->runtime;
395 		if (chip->playback_format == SB_DSP_OUTPUT)
396 		    	snd_sb8_playback_trigger(substream, SNDRV_PCM_TRIGGER_START);
397 		snd_pcm_period_elapsed(substream);
398 		break;
399 	case SB_MODE_CAPTURE_16:
400 		if (chip->hardware != SB_HW_JAZZ16)
401 			break;
402 		/* fallthru */
403 	case SB_MODE_CAPTURE_8:
404 		substream = chip->capture_substream;
405 		runtime = substream->runtime;
406 		if (chip->capture_format == SB_DSP_INPUT)
407 		    	snd_sb8_capture_trigger(substream, SNDRV_PCM_TRIGGER_START);
408 		snd_pcm_period_elapsed(substream);
409 		break;
410 	}
411 	return IRQ_HANDLED;
412 }
413 
414 static snd_pcm_uframes_t snd_sb8_playback_pointer(struct snd_pcm_substream *substream)
415 {
416 	struct snd_sb *chip = snd_pcm_substream_chip(substream);
417 	size_t ptr;
418 	int dma;
419 
420 	if (chip->mode & SB_MODE_PLAYBACK_8)
421 		dma = chip->dma8;
422 	else if (chip->mode & SB_MODE_PLAYBACK_16)
423 		dma = chip->dma16;
424 	else
425 		return 0;
426 	ptr = snd_dma_pointer(dma, chip->p_dma_size);
427 	return bytes_to_frames(substream->runtime, ptr);
428 }
429 
430 static snd_pcm_uframes_t snd_sb8_capture_pointer(struct snd_pcm_substream *substream)
431 {
432 	struct snd_sb *chip = snd_pcm_substream_chip(substream);
433 	size_t ptr;
434 	int dma;
435 
436 	if (chip->mode & SB_MODE_CAPTURE_8)
437 		dma = chip->dma8;
438 	else if (chip->mode & SB_MODE_CAPTURE_16)
439 		dma = chip->dma16;
440 	else
441 		return 0;
442 	ptr = snd_dma_pointer(dma, chip->c_dma_size);
443 	return bytes_to_frames(substream->runtime, ptr);
444 }
445 
446 /*
447 
448  */
449 
450 static struct snd_pcm_hardware snd_sb8_playback =
451 {
452 	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
453 				 SNDRV_PCM_INFO_MMAP_VALID),
454 	.formats =		 SNDRV_PCM_FMTBIT_U8,
455 	.rates =		(SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000 |
456 				 SNDRV_PCM_RATE_11025 | SNDRV_PCM_RATE_22050),
457 	.rate_min =		4000,
458 	.rate_max =		23000,
459 	.channels_min =		1,
460 	.channels_max =		1,
461 	.buffer_bytes_max =	65536,
462 	.period_bytes_min =	64,
463 	.period_bytes_max =	65536,
464 	.periods_min =		1,
465 	.periods_max =		1024,
466 	.fifo_size =		0,
467 };
468 
469 static struct snd_pcm_hardware snd_sb8_capture =
470 {
471 	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
472 				 SNDRV_PCM_INFO_MMAP_VALID),
473 	.formats =		SNDRV_PCM_FMTBIT_U8,
474 	.rates =		(SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000 |
475 				 SNDRV_PCM_RATE_11025),
476 	.rate_min =		4000,
477 	.rate_max =		13000,
478 	.channels_min =		1,
479 	.channels_max =		1,
480 	.buffer_bytes_max =	65536,
481 	.period_bytes_min =	64,
482 	.period_bytes_max =	65536,
483 	.periods_min =		1,
484 	.periods_max =		1024,
485 	.fifo_size =		0,
486 };
487 
488 /*
489  *
490  */
491 
492 static int snd_sb8_open(struct snd_pcm_substream *substream)
493 {
494 	struct snd_sb *chip = snd_pcm_substream_chip(substream);
495 	struct snd_pcm_runtime *runtime = substream->runtime;
496 	unsigned long flags;
497 
498 	spin_lock_irqsave(&chip->open_lock, flags);
499 	if (chip->open) {
500 		spin_unlock_irqrestore(&chip->open_lock, flags);
501 		return -EAGAIN;
502 	}
503 	chip->open |= SB_OPEN_PCM;
504 	spin_unlock_irqrestore(&chip->open_lock, flags);
505 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
506 		chip->playback_substream = substream;
507 		runtime->hw = snd_sb8_playback;
508 	} else {
509 		chip->capture_substream = substream;
510 		runtime->hw = snd_sb8_capture;
511 	}
512 	switch (chip->hardware) {
513 	case SB_HW_JAZZ16:
514 		if (chip->dma16 == 5 || chip->dma16 == 7)
515 			runtime->hw.formats |= SNDRV_PCM_FMTBIT_S16_LE;
516 		runtime->hw.rates |= SNDRV_PCM_RATE_8000_48000;
517 		runtime->hw.rate_min = 4000;
518 		runtime->hw.rate_max = 50000;
519 		runtime->hw.channels_max = 2;
520 		break;
521 	case SB_HW_PRO:
522 		runtime->hw.rate_max = 44100;
523 		runtime->hw.channels_max = 2;
524 		snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
525 				    snd_sb8_hw_constraint_rate_channels, NULL,
526 				    SNDRV_PCM_HW_PARAM_CHANNELS,
527 				    SNDRV_PCM_HW_PARAM_RATE, -1);
528 		snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
529 				     snd_sb8_hw_constraint_channels_rate, NULL,
530 				     SNDRV_PCM_HW_PARAM_RATE, -1);
531 		break;
532 	case SB_HW_201:
533 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
534 			runtime->hw.rate_max = 44100;
535 		} else {
536 			runtime->hw.rate_max = 15000;
537 		}
538 	default:
539 		break;
540 	}
541 	snd_pcm_hw_constraint_ratnums(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
542 				      &hw_constraints_clock);
543 	if (chip->dma8 > 3 || chip->dma16 >= 0) {
544 		snd_pcm_hw_constraint_step(runtime, 0,
545 					   SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 2);
546 		snd_pcm_hw_constraint_step(runtime, 0,
547 					   SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 2);
548 		runtime->hw.buffer_bytes_max = 128 * 1024 * 1024;
549 		runtime->hw.period_bytes_max = 128 * 1024 * 1024;
550 	}
551 	return 0;
552 }
553 
554 static int snd_sb8_close(struct snd_pcm_substream *substream)
555 {
556 	unsigned long flags;
557 	struct snd_sb *chip = snd_pcm_substream_chip(substream);
558 
559 	chip->playback_substream = NULL;
560 	chip->capture_substream = NULL;
561 	spin_lock_irqsave(&chip->open_lock, flags);
562 	chip->open &= ~SB_OPEN_PCM;
563 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
564 		chip->mode &= ~SB_MODE_PLAYBACK;
565 	else
566 		chip->mode &= ~SB_MODE_CAPTURE;
567 	spin_unlock_irqrestore(&chip->open_lock, flags);
568 	return 0;
569 }
570 
571 /*
572  *  Initialization part
573  */
574 
575 static struct snd_pcm_ops snd_sb8_playback_ops = {
576 	.open =			snd_sb8_open,
577 	.close =		snd_sb8_close,
578 	.ioctl =		snd_pcm_lib_ioctl,
579 	.hw_params =		snd_sb8_hw_params,
580 	.hw_free =		snd_sb8_hw_free,
581 	.prepare =		snd_sb8_playback_prepare,
582 	.trigger =		snd_sb8_playback_trigger,
583 	.pointer =		snd_sb8_playback_pointer,
584 };
585 
586 static struct snd_pcm_ops snd_sb8_capture_ops = {
587 	.open =			snd_sb8_open,
588 	.close =		snd_sb8_close,
589 	.ioctl =		snd_pcm_lib_ioctl,
590 	.hw_params =		snd_sb8_hw_params,
591 	.hw_free =		snd_sb8_hw_free,
592 	.prepare =		snd_sb8_capture_prepare,
593 	.trigger =		snd_sb8_capture_trigger,
594 	.pointer =		snd_sb8_capture_pointer,
595 };
596 
597 int snd_sb8dsp_pcm(struct snd_sb *chip, int device, struct snd_pcm ** rpcm)
598 {
599 	struct snd_card *card = chip->card;
600 	struct snd_pcm *pcm;
601 	int err;
602 	size_t max_prealloc = 64 * 1024;
603 
604 	if (rpcm)
605 		*rpcm = NULL;
606 	if ((err = snd_pcm_new(card, "SB8 DSP", device, 1, 1, &pcm)) < 0)
607 		return err;
608 	sprintf(pcm->name, "DSP v%i.%i", chip->version >> 8, chip->version & 0xff);
609 	pcm->info_flags = SNDRV_PCM_INFO_HALF_DUPLEX;
610 	pcm->private_data = chip;
611 
612 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_sb8_playback_ops);
613 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_sb8_capture_ops);
614 
615 	if (chip->dma8 > 3 || chip->dma16 >= 0)
616 		max_prealloc = 128 * 1024;
617 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
618 					      snd_dma_isa_data(),
619 					      64*1024, max_prealloc);
620 
621 	if (rpcm)
622 		*rpcm = pcm;
623 	return 0;
624 }
625 
626 EXPORT_SYMBOL(snd_sb8dsp_pcm);
627 EXPORT_SYMBOL(snd_sb8dsp_interrupt);
628   /* sb8_midi.c */
629 EXPORT_SYMBOL(snd_sb8dsp_midi_interrupt);
630 EXPORT_SYMBOL(snd_sb8dsp_midi);
631 
632 /*
633  *  INIT part
634  */
635 
636 static int __init alsa_sb8_init(void)
637 {
638 	return 0;
639 }
640 
641 static void __exit alsa_sb8_exit(void)
642 {
643 }
644 
645 module_init(alsa_sb8_init)
646 module_exit(alsa_sb8_exit)
647