xref: /openbmc/linux/sound/arm/aaci.c (revision 0da2c47a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/sound/arm/aaci.c - ARM PrimeCell AACI PL041 driver
4  *
5  *  Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
6  *
7  *  Documentation: ARM DDI 0173B
8  */
9 #include <linux/module.h>
10 #include <linux/delay.h>
11 #include <linux/init.h>
12 #include <linux/ioport.h>
13 #include <linux/device.h>
14 #include <linux/spinlock.h>
15 #include <linux/interrupt.h>
16 #include <linux/err.h>
17 #include <linux/amba/bus.h>
18 #include <linux/io.h>
19 
20 #include <sound/core.h>
21 #include <sound/initval.h>
22 #include <sound/ac97_codec.h>
23 #include <sound/pcm.h>
24 #include <sound/pcm_params.h>
25 
26 #include "aaci.h"
27 
28 #define DRIVER_NAME	"aaci-pl041"
29 
30 #define FRAME_PERIOD_US	21
31 
32 /*
33  * PM support is not complete.  Turn it off.
34  */
35 #undef CONFIG_PM
36 
37 static void aaci_ac97_select_codec(struct aaci *aaci, struct snd_ac97 *ac97)
38 {
39 	u32 v, maincr = aaci->maincr | MAINCR_SCRA(ac97->num);
40 
41 	/*
42 	 * Ensure that the slot 1/2 RX registers are empty.
43 	 */
44 	v = readl(aaci->base + AACI_SLFR);
45 	if (v & SLFR_2RXV)
46 		readl(aaci->base + AACI_SL2RX);
47 	if (v & SLFR_1RXV)
48 		readl(aaci->base + AACI_SL1RX);
49 
50 	if (maincr != readl(aaci->base + AACI_MAINCR)) {
51 		writel(maincr, aaci->base + AACI_MAINCR);
52 		readl(aaci->base + AACI_MAINCR);
53 		udelay(1);
54 	}
55 }
56 
57 /*
58  * P29:
59  *  The recommended use of programming the external codec through slot 1
60  *  and slot 2 data is to use the channels during setup routines and the
61  *  slot register at any other time.  The data written into slot 1, slot 2
62  *  and slot 12 registers is transmitted only when their corresponding
63  *  SI1TxEn, SI2TxEn and SI12TxEn bits are set in the AACI_MAINCR
64  *  register.
65  */
66 static void aaci_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
67 			    unsigned short val)
68 {
69 	struct aaci *aaci = ac97->private_data;
70 	int timeout;
71 	u32 v;
72 
73 	if (ac97->num >= 4)
74 		return;
75 
76 	mutex_lock(&aaci->ac97_sem);
77 
78 	aaci_ac97_select_codec(aaci, ac97);
79 
80 	/*
81 	 * P54: You must ensure that AACI_SL2TX is always written
82 	 * to, if required, before data is written to AACI_SL1TX.
83 	 */
84 	writel(val << 4, aaci->base + AACI_SL2TX);
85 	writel(reg << 12, aaci->base + AACI_SL1TX);
86 
87 	/* Initially, wait one frame period */
88 	udelay(FRAME_PERIOD_US);
89 
90 	/* And then wait an additional eight frame periods for it to be sent */
91 	timeout = FRAME_PERIOD_US * 8;
92 	do {
93 		udelay(1);
94 		v = readl(aaci->base + AACI_SLFR);
95 	} while ((v & (SLFR_1TXB|SLFR_2TXB)) && --timeout);
96 
97 	if (v & (SLFR_1TXB|SLFR_2TXB))
98 		dev_err(&aaci->dev->dev,
99 			"timeout waiting for write to complete\n");
100 
101 	mutex_unlock(&aaci->ac97_sem);
102 }
103 
104 /*
105  * Read an AC'97 register.
106  */
107 static unsigned short aaci_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
108 {
109 	struct aaci *aaci = ac97->private_data;
110 	int timeout, retries = 10;
111 	u32 v;
112 
113 	if (ac97->num >= 4)
114 		return ~0;
115 
116 	mutex_lock(&aaci->ac97_sem);
117 
118 	aaci_ac97_select_codec(aaci, ac97);
119 
120 	/*
121 	 * Write the register address to slot 1.
122 	 */
123 	writel((reg << 12) | (1 << 19), aaci->base + AACI_SL1TX);
124 
125 	/* Initially, wait one frame period */
126 	udelay(FRAME_PERIOD_US);
127 
128 	/* And then wait an additional eight frame periods for it to be sent */
129 	timeout = FRAME_PERIOD_US * 8;
130 	do {
131 		udelay(1);
132 		v = readl(aaci->base + AACI_SLFR);
133 	} while ((v & SLFR_1TXB) && --timeout);
134 
135 	if (v & SLFR_1TXB) {
136 		dev_err(&aaci->dev->dev, "timeout on slot 1 TX busy\n");
137 		v = ~0;
138 		goto out;
139 	}
140 
141 	/* Now wait for the response frame */
142 	udelay(FRAME_PERIOD_US);
143 
144 	/* And then wait an additional eight frame periods for data */
145 	timeout = FRAME_PERIOD_US * 8;
146 	do {
147 		udelay(1);
148 		cond_resched();
149 		v = readl(aaci->base + AACI_SLFR) & (SLFR_1RXV|SLFR_2RXV);
150 	} while ((v != (SLFR_1RXV|SLFR_2RXV)) && --timeout);
151 
152 	if (v != (SLFR_1RXV|SLFR_2RXV)) {
153 		dev_err(&aaci->dev->dev, "timeout on RX valid\n");
154 		v = ~0;
155 		goto out;
156 	}
157 
158 	do {
159 		v = readl(aaci->base + AACI_SL1RX) >> 12;
160 		if (v == reg) {
161 			v = readl(aaci->base + AACI_SL2RX) >> 4;
162 			break;
163 		} else if (--retries) {
164 			dev_warn(&aaci->dev->dev,
165 				 "ac97 read back fail.  retry\n");
166 			continue;
167 		} else {
168 			dev_warn(&aaci->dev->dev,
169 				"wrong ac97 register read back (%x != %x)\n",
170 				v, reg);
171 			v = ~0;
172 		}
173 	} while (retries);
174  out:
175 	mutex_unlock(&aaci->ac97_sem);
176 	return v;
177 }
178 
179 static inline void
180 aaci_chan_wait_ready(struct aaci_runtime *aacirun, unsigned long mask)
181 {
182 	u32 val;
183 	int timeout = 5000;
184 
185 	do {
186 		udelay(1);
187 		val = readl(aacirun->base + AACI_SR);
188 	} while (val & mask && timeout--);
189 }
190 
191 
192 
193 /*
194  * Interrupt support.
195  */
196 static void aaci_fifo_irq(struct aaci *aaci, int channel, u32 mask)
197 {
198 	if (mask & ISR_ORINTR) {
199 		dev_warn(&aaci->dev->dev, "RX overrun on chan %d\n", channel);
200 		writel(ICLR_RXOEC1 << channel, aaci->base + AACI_INTCLR);
201 	}
202 
203 	if (mask & ISR_RXTOINTR) {
204 		dev_warn(&aaci->dev->dev, "RX timeout on chan %d\n", channel);
205 		writel(ICLR_RXTOFEC1 << channel, aaci->base + AACI_INTCLR);
206 	}
207 
208 	if (mask & ISR_RXINTR) {
209 		struct aaci_runtime *aacirun = &aaci->capture;
210 		bool period_elapsed = false;
211 		void *ptr;
212 
213 		if (!aacirun->substream || !aacirun->start) {
214 			dev_warn(&aaci->dev->dev, "RX interrupt???\n");
215 			writel(0, aacirun->base + AACI_IE);
216 			return;
217 		}
218 
219 		spin_lock(&aacirun->lock);
220 
221 		ptr = aacirun->ptr;
222 		do {
223 			unsigned int len = aacirun->fifo_bytes;
224 			u32 val;
225 
226 			if (aacirun->bytes <= 0) {
227 				aacirun->bytes += aacirun->period;
228 				period_elapsed = true;
229 			}
230 			if (!(aacirun->cr & CR_EN))
231 				break;
232 
233 			val = readl(aacirun->base + AACI_SR);
234 			if (!(val & SR_RXHF))
235 				break;
236 			if (!(val & SR_RXFF))
237 				len >>= 1;
238 
239 			aacirun->bytes -= len;
240 
241 			/* reading 16 bytes at a time */
242 			for( ; len > 0; len -= 16) {
243 				asm(
244 					"ldmia	%1, {r0, r1, r2, r3}\n\t"
245 					"stmia	%0!, {r0, r1, r2, r3}"
246 					: "+r" (ptr)
247 					: "r" (aacirun->fifo)
248 					: "r0", "r1", "r2", "r3", "cc");
249 
250 				if (ptr >= aacirun->end)
251 					ptr = aacirun->start;
252 			}
253 		} while(1);
254 
255 		aacirun->ptr = ptr;
256 
257 		spin_unlock(&aacirun->lock);
258 
259 		if (period_elapsed)
260 			snd_pcm_period_elapsed(aacirun->substream);
261 	}
262 
263 	if (mask & ISR_URINTR) {
264 		dev_dbg(&aaci->dev->dev, "TX underrun on chan %d\n", channel);
265 		writel(ICLR_TXUEC1 << channel, aaci->base + AACI_INTCLR);
266 	}
267 
268 	if (mask & ISR_TXINTR) {
269 		struct aaci_runtime *aacirun = &aaci->playback;
270 		bool period_elapsed = false;
271 		void *ptr;
272 
273 		if (!aacirun->substream || !aacirun->start) {
274 			dev_warn(&aaci->dev->dev, "TX interrupt???\n");
275 			writel(0, aacirun->base + AACI_IE);
276 			return;
277 		}
278 
279 		spin_lock(&aacirun->lock);
280 
281 		ptr = aacirun->ptr;
282 		do {
283 			unsigned int len = aacirun->fifo_bytes;
284 			u32 val;
285 
286 			if (aacirun->bytes <= 0) {
287 				aacirun->bytes += aacirun->period;
288 				period_elapsed = true;
289 			}
290 			if (!(aacirun->cr & CR_EN))
291 				break;
292 
293 			val = readl(aacirun->base + AACI_SR);
294 			if (!(val & SR_TXHE))
295 				break;
296 			if (!(val & SR_TXFE))
297 				len >>= 1;
298 
299 			aacirun->bytes -= len;
300 
301 			/* writing 16 bytes at a time */
302 			for ( ; len > 0; len -= 16) {
303 				asm(
304 					"ldmia	%0!, {r0, r1, r2, r3}\n\t"
305 					"stmia	%1, {r0, r1, r2, r3}"
306 					: "+r" (ptr)
307 					: "r" (aacirun->fifo)
308 					: "r0", "r1", "r2", "r3", "cc");
309 
310 				if (ptr >= aacirun->end)
311 					ptr = aacirun->start;
312 			}
313 		} while (1);
314 
315 		aacirun->ptr = ptr;
316 
317 		spin_unlock(&aacirun->lock);
318 
319 		if (period_elapsed)
320 			snd_pcm_period_elapsed(aacirun->substream);
321 	}
322 }
323 
324 static irqreturn_t aaci_irq(int irq, void *devid)
325 {
326 	struct aaci *aaci = devid;
327 	u32 mask;
328 	int i;
329 
330 	mask = readl(aaci->base + AACI_ALLINTS);
331 	if (mask) {
332 		u32 m = mask;
333 		for (i = 0; i < 4; i++, m >>= 7) {
334 			if (m & 0x7f) {
335 				aaci_fifo_irq(aaci, i, m);
336 			}
337 		}
338 	}
339 
340 	return mask ? IRQ_HANDLED : IRQ_NONE;
341 }
342 
343 
344 
345 /*
346  * ALSA support.
347  */
348 static const struct snd_pcm_hardware aaci_hw_info = {
349 	.info			= SNDRV_PCM_INFO_MMAP |
350 				  SNDRV_PCM_INFO_MMAP_VALID |
351 				  SNDRV_PCM_INFO_INTERLEAVED |
352 				  SNDRV_PCM_INFO_BLOCK_TRANSFER |
353 				  SNDRV_PCM_INFO_RESUME,
354 
355 	/*
356 	 * ALSA doesn't support 18-bit or 20-bit packed into 32-bit
357 	 * words.  It also doesn't support 12-bit at all.
358 	 */
359 	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
360 
361 	/* rates are setup from the AC'97 codec */
362 	.channels_min		= 2,
363 	.channels_max		= 2,
364 	.buffer_bytes_max	= 64 * 1024,
365 	.period_bytes_min	= 256,
366 	.period_bytes_max	= PAGE_SIZE,
367 	.periods_min		= 4,
368 	.periods_max		= PAGE_SIZE / 16,
369 };
370 
371 /*
372  * We can support two and four channel audio.  Unfortunately
373  * six channel audio requires a non-standard channel ordering:
374  *   2 -> FL(3), FR(4)
375  *   4 -> FL(3), FR(4), SL(7), SR(8)
376  *   6 -> FL(3), FR(4), SL(7), SR(8), C(6), LFE(9) (required)
377  *        FL(3), FR(4), C(6), SL(7), SR(8), LFE(9) (actual)
378  * This requires an ALSA configuration file to correct.
379  */
380 static int aaci_rule_channels(struct snd_pcm_hw_params *p,
381 	struct snd_pcm_hw_rule *rule)
382 {
383 	static unsigned int channel_list[] = { 2, 4, 6 };
384 	struct aaci *aaci = rule->private;
385 	unsigned int mask = 1 << 0, slots;
386 
387 	/* pcms[0] is the our 5.1 PCM instance. */
388 	slots = aaci->ac97_bus->pcms[0].r[0].slots;
389 	if (slots & (1 << AC97_SLOT_PCM_SLEFT)) {
390 		mask |= 1 << 1;
391 		if (slots & (1 << AC97_SLOT_LFE))
392 			mask |= 1 << 2;
393 	}
394 
395 	return snd_interval_list(hw_param_interval(p, rule->var),
396 				 ARRAY_SIZE(channel_list), channel_list, mask);
397 }
398 
399 static int aaci_pcm_open(struct snd_pcm_substream *substream)
400 {
401 	struct snd_pcm_runtime *runtime = substream->runtime;
402 	struct aaci *aaci = substream->private_data;
403 	struct aaci_runtime *aacirun;
404 	int ret = 0;
405 
406 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
407 		aacirun = &aaci->playback;
408 	} else {
409 		aacirun = &aaci->capture;
410 	}
411 
412 	aacirun->substream = substream;
413 	runtime->private_data = aacirun;
414 	runtime->hw = aaci_hw_info;
415 	runtime->hw.rates = aacirun->pcm->rates;
416 	snd_pcm_limit_hw_rates(runtime);
417 
418 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
419 		runtime->hw.channels_max = 6;
420 
421 		/* Add rule describing channel dependency. */
422 		ret = snd_pcm_hw_rule_add(substream->runtime, 0,
423 					  SNDRV_PCM_HW_PARAM_CHANNELS,
424 					  aaci_rule_channels, aaci,
425 					  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
426 		if (ret)
427 			return ret;
428 
429 		if (aacirun->pcm->r[1].slots)
430 			snd_ac97_pcm_double_rate_rules(runtime);
431 	}
432 
433 	/*
434 	 * ALSA wants the byte-size of the FIFOs.  As we only support
435 	 * 16-bit samples, this is twice the FIFO depth irrespective
436 	 * of whether it's in compact mode or not.
437 	 */
438 	runtime->hw.fifo_size = aaci->fifo_depth * 2;
439 
440 	mutex_lock(&aaci->irq_lock);
441 	if (!aaci->users++) {
442 		ret = request_irq(aaci->dev->irq[0], aaci_irq,
443 			   IRQF_SHARED, DRIVER_NAME, aaci);
444 		if (ret != 0)
445 			aaci->users--;
446 	}
447 	mutex_unlock(&aaci->irq_lock);
448 
449 	return ret;
450 }
451 
452 
453 /*
454  * Common ALSA stuff
455  */
456 static int aaci_pcm_close(struct snd_pcm_substream *substream)
457 {
458 	struct aaci *aaci = substream->private_data;
459 	struct aaci_runtime *aacirun = substream->runtime->private_data;
460 
461 	WARN_ON(aacirun->cr & CR_EN);
462 
463 	aacirun->substream = NULL;
464 
465 	mutex_lock(&aaci->irq_lock);
466 	if (!--aaci->users)
467 		free_irq(aaci->dev->irq[0], aaci);
468 	mutex_unlock(&aaci->irq_lock);
469 
470 	return 0;
471 }
472 
473 static int aaci_pcm_hw_free(struct snd_pcm_substream *substream)
474 {
475 	struct aaci_runtime *aacirun = substream->runtime->private_data;
476 
477 	/*
478 	 * This must not be called with the device enabled.
479 	 */
480 	WARN_ON(aacirun->cr & CR_EN);
481 
482 	if (aacirun->pcm_open)
483 		snd_ac97_pcm_close(aacirun->pcm);
484 	aacirun->pcm_open = 0;
485 
486 	return 0;
487 }
488 
489 /* Channel to slot mask */
490 static const u32 channels_to_slotmask[] = {
491 	[2] = CR_SL3 | CR_SL4,
492 	[4] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8,
493 	[6] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8 | CR_SL6 | CR_SL9,
494 };
495 
496 static int aaci_pcm_hw_params(struct snd_pcm_substream *substream,
497 			      struct snd_pcm_hw_params *params)
498 {
499 	struct aaci_runtime *aacirun = substream->runtime->private_data;
500 	struct aaci *aaci = substream->private_data;
501 	unsigned int channels = params_channels(params);
502 	unsigned int rate = params_rate(params);
503 	int dbl = rate > 48000;
504 	int err;
505 
506 	aaci_pcm_hw_free(substream);
507 	if (aacirun->pcm_open) {
508 		snd_ac97_pcm_close(aacirun->pcm);
509 		aacirun->pcm_open = 0;
510 	}
511 
512 	/* channels is already limited to 2, 4, or 6 by aaci_rule_channels */
513 	if (dbl && channels != 2)
514 		return -EINVAL;
515 
516 	err = snd_ac97_pcm_open(aacirun->pcm, rate, channels,
517 				aacirun->pcm->r[dbl].slots);
518 
519 	aacirun->pcm_open = err == 0;
520 	aacirun->cr = CR_FEN | CR_COMPACT | CR_SZ16;
521 	aacirun->cr |= channels_to_slotmask[channels + dbl * 2];
522 
523 	/*
524 	 * fifo_bytes is the number of bytes we transfer to/from
525 	 * the FIFO, including padding.  So that's x4.  As we're
526 	 * in compact mode, the FIFO is half the size.
527 	 */
528 	aacirun->fifo_bytes = aaci->fifo_depth * 4 / 2;
529 
530 	return err;
531 }
532 
533 static int aaci_pcm_prepare(struct snd_pcm_substream *substream)
534 {
535 	struct snd_pcm_runtime *runtime = substream->runtime;
536 	struct aaci_runtime *aacirun = runtime->private_data;
537 
538 	aacirun->period	= snd_pcm_lib_period_bytes(substream);
539 	aacirun->start	= runtime->dma_area;
540 	aacirun->end	= aacirun->start + snd_pcm_lib_buffer_bytes(substream);
541 	aacirun->ptr	= aacirun->start;
542 	aacirun->bytes	= aacirun->period;
543 
544 	return 0;
545 }
546 
547 static snd_pcm_uframes_t aaci_pcm_pointer(struct snd_pcm_substream *substream)
548 {
549 	struct snd_pcm_runtime *runtime = substream->runtime;
550 	struct aaci_runtime *aacirun = runtime->private_data;
551 	ssize_t bytes = aacirun->ptr - aacirun->start;
552 
553 	return bytes_to_frames(runtime, bytes);
554 }
555 
556 
557 /*
558  * Playback specific ALSA stuff
559  */
560 static void aaci_pcm_playback_stop(struct aaci_runtime *aacirun)
561 {
562 	u32 ie;
563 
564 	ie = readl(aacirun->base + AACI_IE);
565 	ie &= ~(IE_URIE|IE_TXIE);
566 	writel(ie, aacirun->base + AACI_IE);
567 	aacirun->cr &= ~CR_EN;
568 	aaci_chan_wait_ready(aacirun, SR_TXB);
569 	writel(aacirun->cr, aacirun->base + AACI_TXCR);
570 }
571 
572 static void aaci_pcm_playback_start(struct aaci_runtime *aacirun)
573 {
574 	u32 ie;
575 
576 	aaci_chan_wait_ready(aacirun, SR_TXB);
577 	aacirun->cr |= CR_EN;
578 
579 	ie = readl(aacirun->base + AACI_IE);
580 	ie |= IE_URIE | IE_TXIE;
581 	writel(ie, aacirun->base + AACI_IE);
582 	writel(aacirun->cr, aacirun->base + AACI_TXCR);
583 }
584 
585 static int aaci_pcm_playback_trigger(struct snd_pcm_substream *substream, int cmd)
586 {
587 	struct aaci_runtime *aacirun = substream->runtime->private_data;
588 	unsigned long flags;
589 	int ret = 0;
590 
591 	spin_lock_irqsave(&aacirun->lock, flags);
592 
593 	switch (cmd) {
594 	case SNDRV_PCM_TRIGGER_START:
595 		aaci_pcm_playback_start(aacirun);
596 		break;
597 
598 	case SNDRV_PCM_TRIGGER_RESUME:
599 		aaci_pcm_playback_start(aacirun);
600 		break;
601 
602 	case SNDRV_PCM_TRIGGER_STOP:
603 		aaci_pcm_playback_stop(aacirun);
604 		break;
605 
606 	case SNDRV_PCM_TRIGGER_SUSPEND:
607 		aaci_pcm_playback_stop(aacirun);
608 		break;
609 
610 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
611 		break;
612 
613 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
614 		break;
615 
616 	default:
617 		ret = -EINVAL;
618 	}
619 
620 	spin_unlock_irqrestore(&aacirun->lock, flags);
621 
622 	return ret;
623 }
624 
625 static const struct snd_pcm_ops aaci_playback_ops = {
626 	.open		= aaci_pcm_open,
627 	.close		= aaci_pcm_close,
628 	.hw_params	= aaci_pcm_hw_params,
629 	.hw_free	= aaci_pcm_hw_free,
630 	.prepare	= aaci_pcm_prepare,
631 	.trigger	= aaci_pcm_playback_trigger,
632 	.pointer	= aaci_pcm_pointer,
633 };
634 
635 static void aaci_pcm_capture_stop(struct aaci_runtime *aacirun)
636 {
637 	u32 ie;
638 
639 	aaci_chan_wait_ready(aacirun, SR_RXB);
640 
641 	ie = readl(aacirun->base + AACI_IE);
642 	ie &= ~(IE_ORIE | IE_RXIE);
643 	writel(ie, aacirun->base+AACI_IE);
644 
645 	aacirun->cr &= ~CR_EN;
646 
647 	writel(aacirun->cr, aacirun->base + AACI_RXCR);
648 }
649 
650 static void aaci_pcm_capture_start(struct aaci_runtime *aacirun)
651 {
652 	u32 ie;
653 
654 	aaci_chan_wait_ready(aacirun, SR_RXB);
655 
656 #ifdef DEBUG
657 	/* RX Timeout value: bits 28:17 in RXCR */
658 	aacirun->cr |= 0xf << 17;
659 #endif
660 
661 	aacirun->cr |= CR_EN;
662 	writel(aacirun->cr, aacirun->base + AACI_RXCR);
663 
664 	ie = readl(aacirun->base + AACI_IE);
665 	ie |= IE_ORIE |IE_RXIE; // overrun and rx interrupt -- half full
666 	writel(ie, aacirun->base + AACI_IE);
667 }
668 
669 static int aaci_pcm_capture_trigger(struct snd_pcm_substream *substream, int cmd)
670 {
671 	struct aaci_runtime *aacirun = substream->runtime->private_data;
672 	unsigned long flags;
673 	int ret = 0;
674 
675 	spin_lock_irqsave(&aacirun->lock, flags);
676 
677 	switch (cmd) {
678 	case SNDRV_PCM_TRIGGER_START:
679 		aaci_pcm_capture_start(aacirun);
680 		break;
681 
682 	case SNDRV_PCM_TRIGGER_RESUME:
683 		aaci_pcm_capture_start(aacirun);
684 		break;
685 
686 	case SNDRV_PCM_TRIGGER_STOP:
687 		aaci_pcm_capture_stop(aacirun);
688 		break;
689 
690 	case SNDRV_PCM_TRIGGER_SUSPEND:
691 		aaci_pcm_capture_stop(aacirun);
692 		break;
693 
694 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
695 		break;
696 
697 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
698 		break;
699 
700 	default:
701 		ret = -EINVAL;
702 	}
703 
704 	spin_unlock_irqrestore(&aacirun->lock, flags);
705 
706 	return ret;
707 }
708 
709 static int aaci_pcm_capture_prepare(struct snd_pcm_substream *substream)
710 {
711 	struct snd_pcm_runtime *runtime = substream->runtime;
712 	struct aaci *aaci = substream->private_data;
713 
714 	aaci_pcm_prepare(substream);
715 
716 	/* allow changing of sample rate */
717 	aaci_ac97_write(aaci->ac97, AC97_EXTENDED_STATUS, 0x0001); /* VRA */
718 	aaci_ac97_write(aaci->ac97, AC97_PCM_LR_ADC_RATE, runtime->rate);
719 	aaci_ac97_write(aaci->ac97, AC97_PCM_MIC_ADC_RATE, runtime->rate);
720 
721 	/* Record select: Mic: 0, Aux: 3, Line: 4 */
722 	aaci_ac97_write(aaci->ac97, AC97_REC_SEL, 0x0404);
723 
724 	return 0;
725 }
726 
727 static const struct snd_pcm_ops aaci_capture_ops = {
728 	.open		= aaci_pcm_open,
729 	.close		= aaci_pcm_close,
730 	.hw_params	= aaci_pcm_hw_params,
731 	.hw_free	= aaci_pcm_hw_free,
732 	.prepare	= aaci_pcm_capture_prepare,
733 	.trigger	= aaci_pcm_capture_trigger,
734 	.pointer	= aaci_pcm_pointer,
735 };
736 
737 /*
738  * Power Management.
739  */
740 #ifdef CONFIG_PM
741 static int aaci_do_suspend(struct snd_card *card)
742 {
743 	struct aaci *aaci = card->private_data;
744 	snd_power_change_state(card, SNDRV_CTL_POWER_D3cold);
745 	return 0;
746 }
747 
748 static int aaci_do_resume(struct snd_card *card)
749 {
750 	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
751 	return 0;
752 }
753 
754 static int aaci_suspend(struct device *dev)
755 {
756 	struct snd_card *card = dev_get_drvdata(dev);
757 	return card ? aaci_do_suspend(card) : 0;
758 }
759 
760 static int aaci_resume(struct device *dev)
761 {
762 	struct snd_card *card = dev_get_drvdata(dev);
763 	return card ? aaci_do_resume(card) : 0;
764 }
765 
766 static SIMPLE_DEV_PM_OPS(aaci_dev_pm_ops, aaci_suspend, aaci_resume);
767 #define AACI_DEV_PM_OPS (&aaci_dev_pm_ops)
768 #else
769 #define AACI_DEV_PM_OPS NULL
770 #endif
771 
772 
773 static const struct ac97_pcm ac97_defs[] = {
774 	[0] = {	/* Front PCM */
775 		.exclusive = 1,
776 		.r = {
777 			[0] = {
778 				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
779 					  (1 << AC97_SLOT_PCM_RIGHT) |
780 					  (1 << AC97_SLOT_PCM_CENTER) |
781 					  (1 << AC97_SLOT_PCM_SLEFT) |
782 					  (1 << AC97_SLOT_PCM_SRIGHT) |
783 					  (1 << AC97_SLOT_LFE),
784 			},
785 			[1] = {
786 				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
787 					  (1 << AC97_SLOT_PCM_RIGHT) |
788 					  (1 << AC97_SLOT_PCM_LEFT_0) |
789 					  (1 << AC97_SLOT_PCM_RIGHT_0),
790 			},
791 		},
792 	},
793 	[1] = {	/* PCM in */
794 		.stream = 1,
795 		.exclusive = 1,
796 		.r = {
797 			[0] = {
798 				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
799 					  (1 << AC97_SLOT_PCM_RIGHT),
800 			},
801 		},
802 	},
803 	[2] = {	/* Mic in */
804 		.stream = 1,
805 		.exclusive = 1,
806 		.r = {
807 			[0] = {
808 				.slots	= (1 << AC97_SLOT_MIC),
809 			},
810 		},
811 	}
812 };
813 
814 static const struct snd_ac97_bus_ops aaci_bus_ops = {
815 	.write	= aaci_ac97_write,
816 	.read	= aaci_ac97_read,
817 };
818 
819 static int aaci_probe_ac97(struct aaci *aaci)
820 {
821 	struct snd_ac97_template ac97_template;
822 	struct snd_ac97_bus *ac97_bus;
823 	struct snd_ac97 *ac97;
824 	int ret;
825 
826 	/*
827 	 * Assert AACIRESET for 2us
828 	 */
829 	writel(0, aaci->base + AACI_RESET);
830 	udelay(2);
831 	writel(RESET_NRST, aaci->base + AACI_RESET);
832 
833 	/*
834 	 * Give the AC'97 codec more than enough time
835 	 * to wake up. (42us = ~2 frames at 48kHz.)
836 	 */
837 	udelay(FRAME_PERIOD_US * 2);
838 
839 	ret = snd_ac97_bus(aaci->card, 0, &aaci_bus_ops, aaci, &ac97_bus);
840 	if (ret)
841 		goto out;
842 
843 	ac97_bus->clock = 48000;
844 	aaci->ac97_bus = ac97_bus;
845 
846 	memset(&ac97_template, 0, sizeof(struct snd_ac97_template));
847 	ac97_template.private_data = aaci;
848 	ac97_template.num = 0;
849 	ac97_template.scaps = AC97_SCAP_SKIP_MODEM;
850 
851 	ret = snd_ac97_mixer(ac97_bus, &ac97_template, &ac97);
852 	if (ret)
853 		goto out;
854 	aaci->ac97 = ac97;
855 
856 	/*
857 	 * Disable AC97 PC Beep input on audio codecs.
858 	 */
859 	if (ac97_is_audio(ac97))
860 		snd_ac97_write_cache(ac97, AC97_PC_BEEP, 0x801e);
861 
862 	ret = snd_ac97_pcm_assign(ac97_bus, ARRAY_SIZE(ac97_defs), ac97_defs);
863 	if (ret)
864 		goto out;
865 
866 	aaci->playback.pcm = &ac97_bus->pcms[0];
867 	aaci->capture.pcm  = &ac97_bus->pcms[1];
868 
869  out:
870 	return ret;
871 }
872 
873 static void aaci_free_card(struct snd_card *card)
874 {
875 	struct aaci *aaci = card->private_data;
876 
877 	iounmap(aaci->base);
878 }
879 
880 static struct aaci *aaci_init_card(struct amba_device *dev)
881 {
882 	struct aaci *aaci;
883 	struct snd_card *card;
884 	int err;
885 
886 	err = snd_card_new(&dev->dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
887 			   THIS_MODULE, sizeof(struct aaci), &card);
888 	if (err < 0)
889 		return NULL;
890 
891 	card->private_free = aaci_free_card;
892 
893 	strlcpy(card->driver, DRIVER_NAME, sizeof(card->driver));
894 	strlcpy(card->shortname, "ARM AC'97 Interface", sizeof(card->shortname));
895 	snprintf(card->longname, sizeof(card->longname),
896 		 "%s PL%03x rev%u at 0x%08llx, irq %d",
897 		 card->shortname, amba_part(dev), amba_rev(dev),
898 		 (unsigned long long)dev->res.start, dev->irq[0]);
899 
900 	aaci = card->private_data;
901 	mutex_init(&aaci->ac97_sem);
902 	mutex_init(&aaci->irq_lock);
903 	aaci->card = card;
904 	aaci->dev = dev;
905 
906 	/* Set MAINCR to allow slot 1 and 2 data IO */
907 	aaci->maincr = MAINCR_IE | MAINCR_SL1RXEN | MAINCR_SL1TXEN |
908 		       MAINCR_SL2RXEN | MAINCR_SL2TXEN;
909 
910 	return aaci;
911 }
912 
913 static int aaci_init_pcm(struct aaci *aaci)
914 {
915 	struct snd_pcm *pcm;
916 	int ret;
917 
918 	ret = snd_pcm_new(aaci->card, "AACI AC'97", 0, 1, 1, &pcm);
919 	if (ret == 0) {
920 		aaci->pcm = pcm;
921 		pcm->private_data = aaci;
922 		pcm->info_flags = 0;
923 
924 		strlcpy(pcm->name, DRIVER_NAME, sizeof(pcm->name));
925 
926 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &aaci_playback_ops);
927 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &aaci_capture_ops);
928 		snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
929 					       aaci->card->dev,
930 					       0, 64 * 1024);
931 	}
932 
933 	return ret;
934 }
935 
936 static unsigned int aaci_size_fifo(struct aaci *aaci)
937 {
938 	struct aaci_runtime *aacirun = &aaci->playback;
939 	int i;
940 
941 	/*
942 	 * Enable the channel, but don't assign it to any slots, so
943 	 * it won't empty onto the AC'97 link.
944 	 */
945 	writel(CR_FEN | CR_SZ16 | CR_EN, aacirun->base + AACI_TXCR);
946 
947 	for (i = 0; !(readl(aacirun->base + AACI_SR) & SR_TXFF) && i < 4096; i++)
948 		writel(0, aacirun->fifo);
949 
950 	writel(0, aacirun->base + AACI_TXCR);
951 
952 	/*
953 	 * Re-initialise the AACI after the FIFO depth test, to
954 	 * ensure that the FIFOs are empty.  Unfortunately, merely
955 	 * disabling the channel doesn't clear the FIFO.
956 	 */
957 	writel(aaci->maincr & ~MAINCR_IE, aaci->base + AACI_MAINCR);
958 	readl(aaci->base + AACI_MAINCR);
959 	udelay(1);
960 	writel(aaci->maincr, aaci->base + AACI_MAINCR);
961 
962 	/*
963 	 * If we hit 4096 entries, we failed.  Go back to the specified
964 	 * fifo depth.
965 	 */
966 	if (i == 4096)
967 		i = 8;
968 
969 	return i;
970 }
971 
972 static int aaci_probe(struct amba_device *dev,
973 		      const struct amba_id *id)
974 {
975 	struct aaci *aaci;
976 	int ret, i;
977 
978 	ret = amba_request_regions(dev, NULL);
979 	if (ret)
980 		return ret;
981 
982 	aaci = aaci_init_card(dev);
983 	if (!aaci) {
984 		ret = -ENOMEM;
985 		goto out;
986 	}
987 
988 	aaci->base = ioremap(dev->res.start, resource_size(&dev->res));
989 	if (!aaci->base) {
990 		ret = -ENOMEM;
991 		goto out;
992 	}
993 
994 	/*
995 	 * Playback uses AACI channel 0
996 	 */
997 	spin_lock_init(&aaci->playback.lock);
998 	aaci->playback.base = aaci->base + AACI_CSCH1;
999 	aaci->playback.fifo = aaci->base + AACI_DR1;
1000 
1001 	/*
1002 	 * Capture uses AACI channel 0
1003 	 */
1004 	spin_lock_init(&aaci->capture.lock);
1005 	aaci->capture.base = aaci->base + AACI_CSCH1;
1006 	aaci->capture.fifo = aaci->base + AACI_DR1;
1007 
1008 	for (i = 0; i < 4; i++) {
1009 		void __iomem *base = aaci->base + i * 0x14;
1010 
1011 		writel(0, base + AACI_IE);
1012 		writel(0, base + AACI_TXCR);
1013 		writel(0, base + AACI_RXCR);
1014 	}
1015 
1016 	writel(0x1fff, aaci->base + AACI_INTCLR);
1017 	writel(aaci->maincr, aaci->base + AACI_MAINCR);
1018 	/*
1019 	 * Fix: ac97 read back fail errors by reading
1020 	 * from any arbitrary aaci register.
1021 	 */
1022 	readl(aaci->base + AACI_CSCH1);
1023 	ret = aaci_probe_ac97(aaci);
1024 	if (ret)
1025 		goto out;
1026 
1027 	/*
1028 	 * Size the FIFOs (must be multiple of 16).
1029 	 * This is the number of entries in the FIFO.
1030 	 */
1031 	aaci->fifo_depth = aaci_size_fifo(aaci);
1032 	if (aaci->fifo_depth & 15) {
1033 		printk(KERN_WARNING "AACI: FIFO depth %d not supported\n",
1034 		       aaci->fifo_depth);
1035 		ret = -ENODEV;
1036 		goto out;
1037 	}
1038 
1039 	ret = aaci_init_pcm(aaci);
1040 	if (ret)
1041 		goto out;
1042 
1043 	ret = snd_card_register(aaci->card);
1044 	if (ret == 0) {
1045 		dev_info(&dev->dev, "%s\n", aaci->card->longname);
1046 		dev_info(&dev->dev, "FIFO %u entries\n", aaci->fifo_depth);
1047 		amba_set_drvdata(dev, aaci->card);
1048 		return ret;
1049 	}
1050 
1051  out:
1052 	if (aaci)
1053 		snd_card_free(aaci->card);
1054 	amba_release_regions(dev);
1055 	return ret;
1056 }
1057 
1058 static int aaci_remove(struct amba_device *dev)
1059 {
1060 	struct snd_card *card = amba_get_drvdata(dev);
1061 
1062 	if (card) {
1063 		struct aaci *aaci = card->private_data;
1064 		writel(0, aaci->base + AACI_MAINCR);
1065 
1066 		snd_card_free(card);
1067 		amba_release_regions(dev);
1068 	}
1069 
1070 	return 0;
1071 }
1072 
1073 static struct amba_id aaci_ids[] = {
1074 	{
1075 		.id	= 0x00041041,
1076 		.mask	= 0x000fffff,
1077 	},
1078 	{ 0, 0 },
1079 };
1080 
1081 MODULE_DEVICE_TABLE(amba, aaci_ids);
1082 
1083 static struct amba_driver aaci_driver = {
1084 	.drv		= {
1085 		.name	= DRIVER_NAME,
1086 		.pm	= AACI_DEV_PM_OPS,
1087 	},
1088 	.probe		= aaci_probe,
1089 	.remove		= aaci_remove,
1090 	.id_table	= aaci_ids,
1091 };
1092 
1093 module_amba_driver(aaci_driver);
1094 
1095 MODULE_LICENSE("GPL");
1096 MODULE_DESCRIPTION("ARM PrimeCell PL041 Advanced Audio CODEC Interface driver");
1097