2 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
3 * Universal interface for Audio Codec '97
5 * For more details look to AC '97 component specification revision 2.2
6 * by Intel Corporation (http://developer.intel.com) and to datasheets
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 #include <sound/driver.h>
27 #include <linux/delay.h>
28 #include <linux/init.h>
29 #include <linux/slab.h>
30 #include <linux/mutex.h>
32 #include <sound/core.h>
33 #include <sound/pcm.h>
34 #include <sound/control.h>
35 #include <sound/ac97_codec.h>
36 #include <sound/asoundef.h>
38 #include "ac97_local.h"
44 static unsigned char rate_reg_tables[2][4][9] = {
48 /* 3&4 front, 7&8 rear, 6&9 center/lfe */
49 AC97_PCM_FRONT_DAC_RATE, /* slot 3 */
50 AC97_PCM_FRONT_DAC_RATE, /* slot 4 */
52 AC97_PCM_LFE_DAC_RATE, /* slot 6 */
53 AC97_PCM_SURR_DAC_RATE, /* slot 7 */
54 AC97_PCM_SURR_DAC_RATE, /* slot 8 */
55 AC97_PCM_LFE_DAC_RATE, /* slot 9 */
60 /* 7&8 front, 6&9 rear, 10&11 center/lfe */
64 AC97_PCM_SURR_DAC_RATE, /* slot 6 */
65 AC97_PCM_FRONT_DAC_RATE, /* slot 7 */
66 AC97_PCM_FRONT_DAC_RATE, /* slot 8 */
67 AC97_PCM_SURR_DAC_RATE, /* slot 9 */
68 AC97_PCM_LFE_DAC_RATE, /* slot 10 */
69 AC97_PCM_LFE_DAC_RATE, /* slot 11 */
72 /* 6&9 front, 10&11 rear, 3&4 center/lfe */
73 AC97_PCM_LFE_DAC_RATE, /* slot 3 */
74 AC97_PCM_LFE_DAC_RATE, /* slot 4 */
76 AC97_PCM_FRONT_DAC_RATE, /* slot 6 */
79 AC97_PCM_FRONT_DAC_RATE, /* slot 9 */
80 AC97_PCM_SURR_DAC_RATE, /* slot 10 */
81 AC97_PCM_SURR_DAC_RATE, /* slot 11 */
84 /* 10&11 front, 3&4 rear, 7&8 center/lfe */
85 AC97_PCM_SURR_DAC_RATE, /* slot 3 */
86 AC97_PCM_SURR_DAC_RATE, /* slot 4 */
89 AC97_PCM_LFE_DAC_RATE, /* slot 7 */
90 AC97_PCM_LFE_DAC_RATE, /* slot 8 */
92 AC97_PCM_FRONT_DAC_RATE, /* slot 10 */
93 AC97_PCM_FRONT_DAC_RATE, /* slot 11 */
99 /* 3&4 front, 7&8 front (t+1) */
100 AC97_PCM_FRONT_DAC_RATE, /* slot 3 */
101 AC97_PCM_FRONT_DAC_RATE, /* slot 4 */
104 AC97_PCM_FRONT_DAC_RATE, /* slot 7 */
105 AC97_PCM_FRONT_DAC_RATE, /* slot 8 */
111 /* not specified in the specification */
146 /* FIXME: more various mappings for ADC? */
147 static unsigned char rate_cregs[9] = {
148 AC97_PCM_LR_ADC_RATE, /* 3 */
149 AC97_PCM_LR_ADC_RATE, /* 4 */
151 AC97_PCM_MIC_ADC_RATE, /* 6 */
159 static unsigned char get_slot_reg(struct ac97_pcm *pcm, unsigned short cidx,
160 unsigned short slot, int dbl)
167 return AC97_SPDIF; /* pseudo register */
168 if (pcm->stream == SNDRV_PCM_STREAM_PLAYBACK)
169 return rate_reg_tables[dbl][pcm->r[dbl].rate_table[cidx]][slot - 3];
171 return rate_cregs[slot - 3];
174 static int set_spdif_rate(struct snd_ac97 *ac97, unsigned short rate)
176 unsigned short old, bits, reg, mask;
179 if (! (ac97->ext_id & AC97_EI_SPDIF))
182 /* TODO: double rate support */
183 if (ac97->flags & AC97_CS_SPDIF) {
185 case 48000: bits = 0; break;
186 case 44100: bits = 1 << AC97_SC_SPSR_SHIFT; break;
187 default: /* invalid - disable output */
188 snd_ac97_update_bits(ac97, AC97_EXTENDED_STATUS, AC97_EA_SPDIF, 0);
191 reg = AC97_CSR_SPDIF;
192 mask = 1 << AC97_SC_SPSR_SHIFT;
194 if (ac97->id == AC97_ID_CM9739 && rate != 48000) {
195 snd_ac97_update_bits(ac97, AC97_EXTENDED_STATUS, AC97_EA_SPDIF, 0);
199 case 44100: bits = AC97_SC_SPSR_44K; break;
200 case 48000: bits = AC97_SC_SPSR_48K; break;
201 case 32000: bits = AC97_SC_SPSR_32K; break;
202 default: /* invalid - disable output */
203 snd_ac97_update_bits(ac97, AC97_EXTENDED_STATUS, AC97_EA_SPDIF, 0);
207 mask = AC97_SC_SPSR_MASK;
210 mutex_lock(&ac97->reg_mutex);
211 old = snd_ac97_read(ac97, reg) & mask;
213 snd_ac97_update_bits_nolock(ac97, AC97_EXTENDED_STATUS, AC97_EA_SPDIF, 0);
214 snd_ac97_update_bits_nolock(ac97, reg, mask, bits);
215 /* update the internal spdif bits */
216 sbits = ac97->spdif_status;
217 if (sbits & IEC958_AES0_PROFESSIONAL) {
218 sbits &= ~IEC958_AES0_PRO_FS;
220 case 44100: sbits |= IEC958_AES0_PRO_FS_44100; break;
221 case 48000: sbits |= IEC958_AES0_PRO_FS_48000; break;
222 case 32000: sbits |= IEC958_AES0_PRO_FS_32000; break;
225 sbits &= ~(IEC958_AES3_CON_FS << 24);
227 case 44100: sbits |= IEC958_AES3_CON_FS_44100<<24; break;
228 case 48000: sbits |= IEC958_AES3_CON_FS_48000<<24; break;
229 case 32000: sbits |= IEC958_AES3_CON_FS_32000<<24; break;
232 ac97->spdif_status = sbits;
234 snd_ac97_update_bits_nolock(ac97, AC97_EXTENDED_STATUS, AC97_EA_SPDIF, AC97_EA_SPDIF);
235 mutex_unlock(&ac97->reg_mutex);
240 * snd_ac97_set_rate - change the rate of the given input/output.
241 * @ac97: the ac97 instance
242 * @reg: the register to change
243 * @rate: the sample rate to set
245 * Changes the rate of the given input/output on the codec.
246 * If the codec doesn't support VAR, the rate must be 48000 (except
249 * The valid registers are AC97_PMC_MIC_ADC_RATE,
250 * AC97_PCM_FRONT_DAC_RATE, AC97_PCM_LR_ADC_RATE.
251 * AC97_PCM_SURR_DAC_RATE and AC97_PCM_LFE_DAC_RATE are accepted
252 * if the codec supports them.
253 * AC97_SPDIF is accepted as a pseudo register to modify the SPDIF
256 * Returns zero if successful, or a negative error code on failure.
258 int snd_ac97_set_rate(struct snd_ac97 *ac97, int reg, unsigned int rate)
265 if (!(ac97->flags & AC97_DOUBLE_RATE))
267 if (reg != AC97_PCM_FRONT_DAC_RATE)
271 snd_ac97_update_power(ac97, reg, 1);
273 case AC97_PCM_MIC_ADC_RATE:
274 if ((ac97->regs[AC97_EXTENDED_STATUS] & AC97_EA_VRM) == 0) /* MIC VRA */
278 case AC97_PCM_FRONT_DAC_RATE:
279 case AC97_PCM_LR_ADC_RATE:
280 if ((ac97->regs[AC97_EXTENDED_STATUS] & AC97_EA_VRA) == 0) /* VRA */
281 if (rate != 48000 && rate != 96000)
284 case AC97_PCM_SURR_DAC_RATE:
285 if (! (ac97->scaps & AC97_SCAP_SURROUND_DAC))
288 case AC97_PCM_LFE_DAC_RATE:
289 if (! (ac97->scaps & AC97_SCAP_CENTER_LFE_DAC))
294 return set_spdif_rate(ac97, rate);
300 tmp = (rate * ac97->bus->clock) / 48000;
303 if ((ac97->ext_id & AC97_EI_DRA) && reg == AC97_PCM_FRONT_DAC_RATE)
304 snd_ac97_update_bits(ac97, AC97_EXTENDED_STATUS,
305 AC97_EA_DRA, dbl ? AC97_EA_DRA : 0);
306 snd_ac97_update(ac97, reg, tmp & 0xffff);
307 snd_ac97_read(ac97, reg);
308 if ((ac97->ext_id & AC97_EI_DRA) && reg == AC97_PCM_FRONT_DAC_RATE) {
309 /* Intel controllers require double rate data to be put in
312 snd_ac97_update_bits(ac97, AC97_GENERAL_PURPOSE,
314 dbl ? AC97_GP_DRSS_78 : 0);
315 snd_ac97_read(ac97, AC97_GENERAL_PURPOSE);
320 EXPORT_SYMBOL(snd_ac97_set_rate);
322 static unsigned short get_pslots(struct snd_ac97 *ac97, unsigned char *rate_table, unsigned short *spdif_slots)
324 if (!ac97_is_audio(ac97))
326 if (ac97_is_rev22(ac97) || ac97_can_amap(ac97)) {
327 unsigned short slots = 0;
328 if (ac97_is_rev22(ac97)) {
329 /* Note: it's simply emulation of AMAP behaviour */
331 es = ac97->regs[AC97_EXTENDED_ID] &= ~AC97_EI_DACS_SLOT_MASK;
332 switch (ac97->addr) {
334 case 2: es |= (1<<AC97_EI_DACS_SLOT_SHIFT); break;
335 case 3: es |= (2<<AC97_EI_DACS_SLOT_SHIFT); break;
337 snd_ac97_write_cache(ac97, AC97_EXTENDED_ID, es);
339 switch (ac97->addr) {
341 slots |= (1<<AC97_SLOT_PCM_LEFT)|(1<<AC97_SLOT_PCM_RIGHT);
342 if (ac97->scaps & AC97_SCAP_SURROUND_DAC)
343 slots |= (1<<AC97_SLOT_PCM_SLEFT)|(1<<AC97_SLOT_PCM_SRIGHT);
344 if (ac97->scaps & AC97_SCAP_CENTER_LFE_DAC)
345 slots |= (1<<AC97_SLOT_PCM_CENTER)|(1<<AC97_SLOT_LFE);
346 if (ac97->ext_id & AC97_EI_SPDIF) {
347 if (!(ac97->scaps & AC97_SCAP_SURROUND_DAC))
348 *spdif_slots = (1<<AC97_SLOT_SPDIF_LEFT)|(1<<AC97_SLOT_SPDIF_RIGHT);
349 else if (!(ac97->scaps & AC97_SCAP_CENTER_LFE_DAC))
350 *spdif_slots = (1<<AC97_SLOT_SPDIF_LEFT1)|(1<<AC97_SLOT_SPDIF_RIGHT1);
352 *spdif_slots = (1<<AC97_SLOT_SPDIF_LEFT2)|(1<<AC97_SLOT_SPDIF_RIGHT2);
358 slots |= (1<<AC97_SLOT_PCM_SLEFT)|(1<<AC97_SLOT_PCM_SRIGHT);
359 if (ac97->scaps & AC97_SCAP_SURROUND_DAC)
360 slots |= (1<<AC97_SLOT_PCM_CENTER)|(1<<AC97_SLOT_LFE);
361 if (ac97->ext_id & AC97_EI_SPDIF) {
362 if (!(ac97->scaps & AC97_SCAP_SURROUND_DAC))
363 *spdif_slots = (1<<AC97_SLOT_SPDIF_LEFT1)|(1<<AC97_SLOT_SPDIF_RIGHT1);
365 *spdif_slots = (1<<AC97_SLOT_SPDIF_LEFT2)|(1<<AC97_SLOT_SPDIF_RIGHT2);
370 slots |= (1<<AC97_SLOT_PCM_CENTER)|(1<<AC97_SLOT_LFE);
371 if (ac97->ext_id & AC97_EI_SPDIF)
372 *spdif_slots = (1<<AC97_SLOT_SPDIF_LEFT2)|(1<<AC97_SLOT_SPDIF_RIGHT2);
378 unsigned short slots;
379 slots = (1<<AC97_SLOT_PCM_LEFT)|(1<<AC97_SLOT_PCM_RIGHT);
380 if (ac97->scaps & AC97_SCAP_SURROUND_DAC)
381 slots |= (1<<AC97_SLOT_PCM_SLEFT)|(1<<AC97_SLOT_PCM_SRIGHT);
382 if (ac97->scaps & AC97_SCAP_CENTER_LFE_DAC)
383 slots |= (1<<AC97_SLOT_PCM_CENTER)|(1<<AC97_SLOT_LFE);
384 if (ac97->ext_id & AC97_EI_SPDIF) {
385 if (!(ac97->scaps & AC97_SCAP_SURROUND_DAC))
386 *spdif_slots = (1<<AC97_SLOT_SPDIF_LEFT)|(1<<AC97_SLOT_SPDIF_RIGHT);
387 else if (!(ac97->scaps & AC97_SCAP_CENTER_LFE_DAC))
388 *spdif_slots = (1<<AC97_SLOT_SPDIF_LEFT1)|(1<<AC97_SLOT_SPDIF_RIGHT1);
390 *spdif_slots = (1<<AC97_SLOT_SPDIF_LEFT2)|(1<<AC97_SLOT_SPDIF_RIGHT2);
397 static unsigned short get_cslots(struct snd_ac97 *ac97)
399 unsigned short slots;
401 if (!ac97_is_audio(ac97))
403 slots = (1<<AC97_SLOT_PCM_LEFT)|(1<<AC97_SLOT_PCM_RIGHT);
404 slots |= (1<<AC97_SLOT_MIC);
408 static unsigned int get_rates(struct ac97_pcm *pcm, unsigned int cidx, unsigned short slots, int dbl)
411 unsigned int rates = ~0;
414 for (i = 3; i < 12; i++) {
415 if (!(slots & (1 << i)))
417 reg = get_slot_reg(pcm, cidx, i, dbl);
419 case AC97_PCM_FRONT_DAC_RATE: idx = AC97_RATES_FRONT_DAC; break;
420 case AC97_PCM_SURR_DAC_RATE: idx = AC97_RATES_SURR_DAC; break;
421 case AC97_PCM_LFE_DAC_RATE: idx = AC97_RATES_LFE_DAC; break;
422 case AC97_PCM_LR_ADC_RATE: idx = AC97_RATES_ADC; break;
423 case AC97_PCM_MIC_ADC_RATE: idx = AC97_RATES_MIC_ADC; break;
424 default: idx = AC97_RATES_SPDIF; break;
426 rates &= pcm->r[dbl].codec[cidx]->rates[idx];
429 rates &= ~(SNDRV_PCM_RATE_64000 | SNDRV_PCM_RATE_88200 |
430 SNDRV_PCM_RATE_96000);
435 * snd_ac97_pcm_assign - assign AC97 slots to given PCM streams
436 * @bus: the ac97 bus instance
437 * @pcms_count: count of PCMs to be assigned
438 * @pcms: PCMs to be assigned
440 * It assigns available AC97 slots for given PCMs. If none or only
441 * some slots are available, pcm->xxx.slots and pcm->xxx.rslots[] members
442 * are reduced and might be zero.
444 int snd_ac97_pcm_assign(struct snd_ac97_bus *bus,
445 unsigned short pcms_count,
446 const struct ac97_pcm *pcms)
449 const struct ac97_pcm *pcm;
450 struct ac97_pcm *rpcms, *rpcm;
451 unsigned short avail_slots[2][4];
452 unsigned char rate_table[2][4];
453 unsigned short tmp, slots;
454 unsigned short spdif_slots[4];
456 struct snd_ac97 *codec;
458 rpcms = kcalloc(pcms_count, sizeof(struct ac97_pcm), GFP_KERNEL);
461 memset(avail_slots, 0, sizeof(avail_slots));
462 memset(rate_table, 0, sizeof(rate_table));
463 memset(spdif_slots, 0, sizeof(spdif_slots));
464 for (i = 0; i < 4; i++) {
465 codec = bus->codec[i];
468 avail_slots[0][i] = get_pslots(codec, &rate_table[0][i], &spdif_slots[i]);
469 avail_slots[1][i] = get_cslots(codec);
470 if (!(codec->scaps & AC97_SCAP_INDEP_SDIN)) {
471 for (j = 0; j < i; j++) {
473 avail_slots[1][i] &= ~avail_slots[1][j];
477 /* first step - exclusive devices */
478 for (i = 0; i < pcms_count; i++) {
481 /* low-level driver thinks that it's more clever */
482 if (pcm->copy_flag) {
486 rpcm->stream = pcm->stream;
487 rpcm->exclusive = pcm->exclusive;
488 rpcm->spdif = pcm->spdif;
489 rpcm->private_value = pcm->private_value;
492 slots = pcm->r[0].slots;
493 for (j = 0; j < 4 && slots; j++) {
497 if (pcm->spdif && pcm->stream == 0)
498 tmp = spdif_slots[j];
500 tmp = avail_slots[pcm->stream][j];
501 if (pcm->exclusive) {
502 /* exclusive access */
504 for (k = 0; k < i; k++) {
505 if (rpcm->stream == rpcms[k].stream)
506 tmp &= ~rpcms[k].r[0].rslots[j];
509 /* non-exclusive access */
510 tmp &= pcm->r[0].slots;
513 rpcm->r[0].rslots[j] = tmp;
514 rpcm->r[0].codec[j] = bus->codec[j];
515 rpcm->r[0].rate_table[j] = rate_table[pcm->stream][j];
517 rates = SNDRV_PCM_RATE_48000;
519 rates = get_rates(rpcm, j, tmp, 0);
521 avail_slots[pcm->stream][j] &= ~tmp;
524 rpcm->r[0].slots |= tmp;
525 rpcm->rates &= rates;
527 /* for double rate, we check the first codec only */
528 if (pcm->stream == SNDRV_PCM_STREAM_PLAYBACK &&
529 bus->codec[0] && (bus->codec[0]->flags & AC97_DOUBLE_RATE) &&
530 rate_table[pcm->stream][0] == 0) {
531 tmp = (1<<AC97_SLOT_PCM_LEFT) | (1<<AC97_SLOT_PCM_RIGHT) |
532 (1<<AC97_SLOT_PCM_LEFT_0) | (1<<AC97_SLOT_PCM_RIGHT_0);
533 if ((tmp & pcm->r[1].slots) == tmp) {
534 rpcm->r[1].slots = tmp;
535 rpcm->r[1].rslots[0] = tmp;
536 rpcm->r[1].rate_table[0] = 0;
537 rpcm->r[1].codec[0] = bus->codec[0];
539 avail_slots[pcm->stream][0] &= ~tmp;
541 rates = SNDRV_PCM_RATE_96000;
543 rates = get_rates(rpcm, 0, tmp, 1);
544 rpcm->rates |= rates;
547 if (rpcm->rates == ~0)
548 rpcm->rates = 0; /* not used */
550 bus->pcms_count = pcms_count;
555 EXPORT_SYMBOL(snd_ac97_pcm_assign);
558 * snd_ac97_pcm_open - opens the given AC97 pcm
559 * @pcm: the ac97 pcm instance
560 * @rate: rate in Hz, if codec does not support VRA, this value must be 48000Hz
561 * @cfg: output stream characteristics
562 * @slots: a subset of allocated slots (snd_ac97_pcm_assign) for this pcm
564 * It locks the specified slots and sets the given rate to AC97 registers.
566 int snd_ac97_pcm_open(struct ac97_pcm *pcm, unsigned int rate,
567 enum ac97_pcm_cfg cfg, unsigned short slots)
569 struct snd_ac97_bus *bus;
570 int i, cidx, r, ok_flag;
571 unsigned int reg_ok[4] = {0,0,0,0};
577 if (cfg == AC97_PCM_CFG_SPDIF) {
579 for (cidx = 0; cidx < 4; cidx++)
580 if (bus->codec[cidx] && (bus->codec[cidx]->ext_id & AC97_EI_SPDIF)) {
581 err = set_spdif_rate(bus->codec[cidx], rate);
586 spin_lock_irq(&pcm->bus->bus_lock);
587 for (i = 3; i < 12; i++) {
588 if (!(slots & (1 << i)))
591 for (cidx = 0; cidx < 4; cidx++) {
592 if (bus->used_slots[pcm->stream][cidx] & (1 << i)) {
593 spin_unlock_irq(&pcm->bus->bus_lock);
597 if (pcm->r[r].rslots[cidx] & (1 << i)) {
598 bus->used_slots[pcm->stream][cidx] |= (1 << i);
603 spin_unlock_irq(&pcm->bus->bus_lock);
604 snd_printk(KERN_ERR "cannot find configuration for AC97 slot %i\n", i);
610 spin_unlock_irq(&pcm->bus->bus_lock);
611 for (i = 3; i < 12; i++) {
612 if (!(slots & (1 << i)))
614 for (cidx = 0; cidx < 4; cidx++) {
615 if (pcm->r[r].rslots[cidx] & (1 << i)) {
616 reg = get_slot_reg(pcm, cidx, i, r);
618 snd_printk(KERN_ERR "invalid AC97 slot %i?\n", i);
621 if (reg_ok[cidx] & (1 << (reg - AC97_PCM_FRONT_DAC_RATE)))
623 //printk(KERN_DEBUG "setting ac97 reg 0x%x to rate %d\n", reg, rate);
624 err = snd_ac97_set_rate(pcm->r[r].codec[cidx], reg, rate);
626 snd_printk(KERN_ERR "error in snd_ac97_set_rate: cidx=%d, reg=0x%x, rate=%d, err=%d\n", cidx, reg, rate, err);
628 reg_ok[cidx] |= (1 << (reg - AC97_PCM_FRONT_DAC_RATE));
637 snd_ac97_pcm_close(pcm);
641 EXPORT_SYMBOL(snd_ac97_pcm_open);
644 * snd_ac97_pcm_close - closes the given AC97 pcm
645 * @pcm: the ac97 pcm instance
647 * It frees the locked AC97 slots.
649 int snd_ac97_pcm_close(struct ac97_pcm *pcm)
651 struct snd_ac97_bus *bus;
652 unsigned short slots = pcm->aslots;
655 #ifdef CONFIG_SND_AC97_POWER_SAVE
656 int r = pcm->cur_dbl;
657 for (i = 3; i < 12; i++) {
658 if (!(slots & (1 << i)))
660 for (cidx = 0; cidx < 4; cidx++) {
661 if (pcm->r[r].rslots[cidx] & (1 << i)) {
662 int reg = get_slot_reg(pcm, cidx, i, r);
663 snd_ac97_update_power(pcm->r[r].codec[cidx],
671 spin_lock_irq(&pcm->bus->bus_lock);
672 for (i = 3; i < 12; i++) {
673 if (!(slots & (1 << i)))
675 for (cidx = 0; cidx < 4; cidx++)
676 bus->used_slots[pcm->stream][cidx] &= ~(1 << i);
680 spin_unlock_irq(&pcm->bus->bus_lock);
684 EXPORT_SYMBOL(snd_ac97_pcm_close);
686 static int double_rate_hw_constraint_rate(struct snd_pcm_hw_params *params,
687 struct snd_pcm_hw_rule *rule)
689 struct snd_interval *channels = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
690 if (channels->min > 2) {
691 static const struct snd_interval single_rates = {
695 struct snd_interval *rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
696 return snd_interval_refine(rate, &single_rates);
701 static int double_rate_hw_constraint_channels(struct snd_pcm_hw_params *params,
702 struct snd_pcm_hw_rule *rule)
704 struct snd_interval *rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
705 if (rate->min > 48000) {
706 static const struct snd_interval double_rate_channels = {
710 struct snd_interval *channels = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
711 return snd_interval_refine(channels, &double_rate_channels);
717 * snd_ac97_pcm_double_rate_rules - set double rate constraints
718 * @runtime: the runtime of the ac97 front playback pcm
720 * Installs the hardware constraint rules to prevent using double rates and
721 * more than two channels at the same time.
723 int snd_ac97_pcm_double_rate_rules(struct snd_pcm_runtime *runtime)
727 err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
728 double_rate_hw_constraint_rate, NULL,
729 SNDRV_PCM_HW_PARAM_CHANNELS, -1);
732 err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
733 double_rate_hw_constraint_channels, NULL,
734 SNDRV_PCM_HW_PARAM_RATE, -1);
738 EXPORT_SYMBOL(snd_ac97_pcm_double_rate_rules);