xref: /linux/sound/arm/aaci.c (revision 4e0ae876f77bc01a7e77724dea57b4b82bd53244)
1 /*
2  *  linux/sound/arm/aaci.c - ARM PrimeCell AACI PL041 driver
3  *
4  *  Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  *  Documentation: ARM DDI 0173B
11  */
12 #include <linux/module.h>
13 #include <linux/delay.h>
14 #include <linux/init.h>
15 #include <linux/ioport.h>
16 #include <linux/device.h>
17 #include <linux/spinlock.h>
18 #include <linux/interrupt.h>
19 #include <linux/err.h>
20 #include <linux/amba/bus.h>
21 #include <linux/io.h>
22 
23 #include <sound/core.h>
24 #include <sound/initval.h>
25 #include <sound/ac97_codec.h>
26 #include <sound/pcm.h>
27 #include <sound/pcm_params.h>
28 
29 #include "aaci.h"
30 
31 #define DRIVER_NAME	"aaci-pl041"
32 
33 #define FRAME_PERIOD_US	21
34 
35 /*
36  * PM support is not complete.  Turn it off.
37  */
38 #undef CONFIG_PM
39 
40 static void aaci_ac97_select_codec(struct aaci *aaci, struct snd_ac97 *ac97)
41 {
42 	u32 v, maincr = aaci->maincr | MAINCR_SCRA(ac97->num);
43 
44 	/*
45 	 * Ensure that the slot 1/2 RX registers are empty.
46 	 */
47 	v = readl(aaci->base + AACI_SLFR);
48 	if (v & SLFR_2RXV)
49 		readl(aaci->base + AACI_SL2RX);
50 	if (v & SLFR_1RXV)
51 		readl(aaci->base + AACI_SL1RX);
52 
53 	if (maincr != readl(aaci->base + AACI_MAINCR)) {
54 		writel(maincr, aaci->base + AACI_MAINCR);
55 		readl(aaci->base + AACI_MAINCR);
56 		udelay(1);
57 	}
58 }
59 
60 /*
61  * P29:
62  *  The recommended use of programming the external codec through slot 1
63  *  and slot 2 data is to use the channels during setup routines and the
64  *  slot register at any other time.  The data written into slot 1, slot 2
65  *  and slot 12 registers is transmitted only when their corresponding
66  *  SI1TxEn, SI2TxEn and SI12TxEn bits are set in the AACI_MAINCR
67  *  register.
68  */
69 static void aaci_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
70 			    unsigned short val)
71 {
72 	struct aaci *aaci = ac97->private_data;
73 	int timeout;
74 	u32 v;
75 
76 	if (ac97->num >= 4)
77 		return;
78 
79 	mutex_lock(&aaci->ac97_sem);
80 
81 	aaci_ac97_select_codec(aaci, ac97);
82 
83 	/*
84 	 * P54: You must ensure that AACI_SL2TX is always written
85 	 * to, if required, before data is written to AACI_SL1TX.
86 	 */
87 	writel(val << 4, aaci->base + AACI_SL2TX);
88 	writel(reg << 12, aaci->base + AACI_SL1TX);
89 
90 	/* Initially, wait one frame period */
91 	udelay(FRAME_PERIOD_US);
92 
93 	/* And then wait an additional eight frame periods for it to be sent */
94 	timeout = FRAME_PERIOD_US * 8;
95 	do {
96 		udelay(1);
97 		v = readl(aaci->base + AACI_SLFR);
98 	} while ((v & (SLFR_1TXB|SLFR_2TXB)) && --timeout);
99 
100 	if (v & (SLFR_1TXB|SLFR_2TXB))
101 		dev_err(&aaci->dev->dev,
102 			"timeout waiting for write to complete\n");
103 
104 	mutex_unlock(&aaci->ac97_sem);
105 }
106 
107 /*
108  * Read an AC'97 register.
109  */
110 static unsigned short aaci_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
111 {
112 	struct aaci *aaci = ac97->private_data;
113 	int timeout, retries = 10;
114 	u32 v;
115 
116 	if (ac97->num >= 4)
117 		return ~0;
118 
119 	mutex_lock(&aaci->ac97_sem);
120 
121 	aaci_ac97_select_codec(aaci, ac97);
122 
123 	/*
124 	 * Write the register address to slot 1.
125 	 */
126 	writel((reg << 12) | (1 << 19), aaci->base + AACI_SL1TX);
127 
128 	/* Initially, wait one frame period */
129 	udelay(FRAME_PERIOD_US);
130 
131 	/* And then wait an additional eight frame periods for it to be sent */
132 	timeout = FRAME_PERIOD_US * 8;
133 	do {
134 		udelay(1);
135 		v = readl(aaci->base + AACI_SLFR);
136 	} while ((v & SLFR_1TXB) && --timeout);
137 
138 	if (v & SLFR_1TXB) {
139 		dev_err(&aaci->dev->dev, "timeout on slot 1 TX busy\n");
140 		v = ~0;
141 		goto out;
142 	}
143 
144 	/* Now wait for the response frame */
145 	udelay(FRAME_PERIOD_US);
146 
147 	/* And then wait an additional eight frame periods for data */
148 	timeout = FRAME_PERIOD_US * 8;
149 	do {
150 		udelay(1);
151 		cond_resched();
152 		v = readl(aaci->base + AACI_SLFR) & (SLFR_1RXV|SLFR_2RXV);
153 	} while ((v != (SLFR_1RXV|SLFR_2RXV)) && --timeout);
154 
155 	if (v != (SLFR_1RXV|SLFR_2RXV)) {
156 		dev_err(&aaci->dev->dev, "timeout on RX valid\n");
157 		v = ~0;
158 		goto out;
159 	}
160 
161 	do {
162 		v = readl(aaci->base + AACI_SL1RX) >> 12;
163 		if (v == reg) {
164 			v = readl(aaci->base + AACI_SL2RX) >> 4;
165 			break;
166 		} else if (--retries) {
167 			dev_warn(&aaci->dev->dev,
168 				 "ac97 read back fail.  retry\n");
169 			continue;
170 		} else {
171 			dev_warn(&aaci->dev->dev,
172 				"wrong ac97 register read back (%x != %x)\n",
173 				v, reg);
174 			v = ~0;
175 		}
176 	} while (retries);
177  out:
178 	mutex_unlock(&aaci->ac97_sem);
179 	return v;
180 }
181 
182 static inline void
183 aaci_chan_wait_ready(struct aaci_runtime *aacirun, unsigned long mask)
184 {
185 	u32 val;
186 	int timeout = 5000;
187 
188 	do {
189 		udelay(1);
190 		val = readl(aacirun->base + AACI_SR);
191 	} while (val & mask && timeout--);
192 }
193 
194 
195 
196 /*
197  * Interrupt support.
198  */
199 static void aaci_fifo_irq(struct aaci *aaci, int channel, u32 mask)
200 {
201 	if (mask & ISR_ORINTR) {
202 		dev_warn(&aaci->dev->dev, "RX overrun on chan %d\n", channel);
203 		writel(ICLR_RXOEC1 << channel, aaci->base + AACI_INTCLR);
204 	}
205 
206 	if (mask & ISR_RXTOINTR) {
207 		dev_warn(&aaci->dev->dev, "RX timeout on chan %d\n", channel);
208 		writel(ICLR_RXTOFEC1 << channel, aaci->base + AACI_INTCLR);
209 	}
210 
211 	if (mask & ISR_RXINTR) {
212 		struct aaci_runtime *aacirun = &aaci->capture;
213 		bool period_elapsed = false;
214 		void *ptr;
215 
216 		if (!aacirun->substream || !aacirun->start) {
217 			dev_warn(&aaci->dev->dev, "RX interrupt???\n");
218 			writel(0, aacirun->base + AACI_IE);
219 			return;
220 		}
221 
222 		spin_lock(&aacirun->lock);
223 
224 		ptr = aacirun->ptr;
225 		do {
226 			unsigned int len = aacirun->fifo_bytes;
227 			u32 val;
228 
229 			if (aacirun->bytes <= 0) {
230 				aacirun->bytes += aacirun->period;
231 				period_elapsed = true;
232 			}
233 			if (!(aacirun->cr & CR_EN))
234 				break;
235 
236 			val = readl(aacirun->base + AACI_SR);
237 			if (!(val & SR_RXHF))
238 				break;
239 			if (!(val & SR_RXFF))
240 				len >>= 1;
241 
242 			aacirun->bytes -= len;
243 
244 			/* reading 16 bytes at a time */
245 			for( ; len > 0; len -= 16) {
246 				asm(
247 					"ldmia	%1, {r0, r1, r2, r3}\n\t"
248 					"stmia	%0!, {r0, r1, r2, r3}"
249 					: "+r" (ptr)
250 					: "r" (aacirun->fifo)
251 					: "r0", "r1", "r2", "r3", "cc");
252 
253 				if (ptr >= aacirun->end)
254 					ptr = aacirun->start;
255 			}
256 		} while(1);
257 
258 		aacirun->ptr = ptr;
259 
260 		spin_unlock(&aacirun->lock);
261 
262 		if (period_elapsed)
263 			snd_pcm_period_elapsed(aacirun->substream);
264 	}
265 
266 	if (mask & ISR_URINTR) {
267 		dev_dbg(&aaci->dev->dev, "TX underrun on chan %d\n", channel);
268 		writel(ICLR_TXUEC1 << channel, aaci->base + AACI_INTCLR);
269 	}
270 
271 	if (mask & ISR_TXINTR) {
272 		struct aaci_runtime *aacirun = &aaci->playback;
273 		bool period_elapsed = false;
274 		void *ptr;
275 
276 		if (!aacirun->substream || !aacirun->start) {
277 			dev_warn(&aaci->dev->dev, "TX interrupt???\n");
278 			writel(0, aacirun->base + AACI_IE);
279 			return;
280 		}
281 
282 		spin_lock(&aacirun->lock);
283 
284 		ptr = aacirun->ptr;
285 		do {
286 			unsigned int len = aacirun->fifo_bytes;
287 			u32 val;
288 
289 			if (aacirun->bytes <= 0) {
290 				aacirun->bytes += aacirun->period;
291 				period_elapsed = true;
292 			}
293 			if (!(aacirun->cr & CR_EN))
294 				break;
295 
296 			val = readl(aacirun->base + AACI_SR);
297 			if (!(val & SR_TXHE))
298 				break;
299 			if (!(val & SR_TXFE))
300 				len >>= 1;
301 
302 			aacirun->bytes -= len;
303 
304 			/* writing 16 bytes at a time */
305 			for ( ; len > 0; len -= 16) {
306 				asm(
307 					"ldmia	%0!, {r0, r1, r2, r3}\n\t"
308 					"stmia	%1, {r0, r1, r2, r3}"
309 					: "+r" (ptr)
310 					: "r" (aacirun->fifo)
311 					: "r0", "r1", "r2", "r3", "cc");
312 
313 				if (ptr >= aacirun->end)
314 					ptr = aacirun->start;
315 			}
316 		} while (1);
317 
318 		aacirun->ptr = ptr;
319 
320 		spin_unlock(&aacirun->lock);
321 
322 		if (period_elapsed)
323 			snd_pcm_period_elapsed(aacirun->substream);
324 	}
325 }
326 
327 static irqreturn_t aaci_irq(int irq, void *devid)
328 {
329 	struct aaci *aaci = devid;
330 	u32 mask;
331 	int i;
332 
333 	mask = readl(aaci->base + AACI_ALLINTS);
334 	if (mask) {
335 		u32 m = mask;
336 		for (i = 0; i < 4; i++, m >>= 7) {
337 			if (m & 0x7f) {
338 				aaci_fifo_irq(aaci, i, m);
339 			}
340 		}
341 	}
342 
343 	return mask ? IRQ_HANDLED : IRQ_NONE;
344 }
345 
346 
347 
348 /*
349  * ALSA support.
350  */
351 static const struct snd_pcm_hardware aaci_hw_info = {
352 	.info			= SNDRV_PCM_INFO_MMAP |
353 				  SNDRV_PCM_INFO_MMAP_VALID |
354 				  SNDRV_PCM_INFO_INTERLEAVED |
355 				  SNDRV_PCM_INFO_BLOCK_TRANSFER |
356 				  SNDRV_PCM_INFO_RESUME,
357 
358 	/*
359 	 * ALSA doesn't support 18-bit or 20-bit packed into 32-bit
360 	 * words.  It also doesn't support 12-bit at all.
361 	 */
362 	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
363 
364 	/* rates are setup from the AC'97 codec */
365 	.channels_min		= 2,
366 	.channels_max		= 2,
367 	.buffer_bytes_max	= 64 * 1024,
368 	.period_bytes_min	= 256,
369 	.period_bytes_max	= PAGE_SIZE,
370 	.periods_min		= 4,
371 	.periods_max		= PAGE_SIZE / 16,
372 };
373 
374 /*
375  * We can support two and four channel audio.  Unfortunately
376  * six channel audio requires a non-standard channel ordering:
377  *   2 -> FL(3), FR(4)
378  *   4 -> FL(3), FR(4), SL(7), SR(8)
379  *   6 -> FL(3), FR(4), SL(7), SR(8), C(6), LFE(9) (required)
380  *        FL(3), FR(4), C(6), SL(7), SR(8), LFE(9) (actual)
381  * This requires an ALSA configuration file to correct.
382  */
383 static int aaci_rule_channels(struct snd_pcm_hw_params *p,
384 	struct snd_pcm_hw_rule *rule)
385 {
386 	static unsigned int channel_list[] = { 2, 4, 6 };
387 	struct aaci *aaci = rule->private;
388 	unsigned int mask = 1 << 0, slots;
389 
390 	/* pcms[0] is the our 5.1 PCM instance. */
391 	slots = aaci->ac97_bus->pcms[0].r[0].slots;
392 	if (slots & (1 << AC97_SLOT_PCM_SLEFT)) {
393 		mask |= 1 << 1;
394 		if (slots & (1 << AC97_SLOT_LFE))
395 			mask |= 1 << 2;
396 	}
397 
398 	return snd_interval_list(hw_param_interval(p, rule->var),
399 				 ARRAY_SIZE(channel_list), channel_list, mask);
400 }
401 
402 static int aaci_pcm_open(struct snd_pcm_substream *substream)
403 {
404 	struct snd_pcm_runtime *runtime = substream->runtime;
405 	struct aaci *aaci = substream->private_data;
406 	struct aaci_runtime *aacirun;
407 	int ret = 0;
408 
409 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
410 		aacirun = &aaci->playback;
411 	} else {
412 		aacirun = &aaci->capture;
413 	}
414 
415 	aacirun->substream = substream;
416 	runtime->private_data = aacirun;
417 	runtime->hw = aaci_hw_info;
418 	runtime->hw.rates = aacirun->pcm->rates;
419 	snd_pcm_limit_hw_rates(runtime);
420 
421 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
422 		runtime->hw.channels_max = 6;
423 
424 		/* Add rule describing channel dependency. */
425 		ret = snd_pcm_hw_rule_add(substream->runtime, 0,
426 					  SNDRV_PCM_HW_PARAM_CHANNELS,
427 					  aaci_rule_channels, aaci,
428 					  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
429 		if (ret)
430 			return ret;
431 
432 		if (aacirun->pcm->r[1].slots)
433 			snd_ac97_pcm_double_rate_rules(runtime);
434 	}
435 
436 	/*
437 	 * ALSA wants the byte-size of the FIFOs.  As we only support
438 	 * 16-bit samples, this is twice the FIFO depth irrespective
439 	 * of whether it's in compact mode or not.
440 	 */
441 	runtime->hw.fifo_size = aaci->fifo_depth * 2;
442 
443 	mutex_lock(&aaci->irq_lock);
444 	if (!aaci->users++) {
445 		ret = request_irq(aaci->dev->irq[0], aaci_irq,
446 			   IRQF_SHARED, DRIVER_NAME, aaci);
447 		if (ret != 0)
448 			aaci->users--;
449 	}
450 	mutex_unlock(&aaci->irq_lock);
451 
452 	return ret;
453 }
454 
455 
456 /*
457  * Common ALSA stuff
458  */
459 static int aaci_pcm_close(struct snd_pcm_substream *substream)
460 {
461 	struct aaci *aaci = substream->private_data;
462 	struct aaci_runtime *aacirun = substream->runtime->private_data;
463 
464 	WARN_ON(aacirun->cr & CR_EN);
465 
466 	aacirun->substream = NULL;
467 
468 	mutex_lock(&aaci->irq_lock);
469 	if (!--aaci->users)
470 		free_irq(aaci->dev->irq[0], aaci);
471 	mutex_unlock(&aaci->irq_lock);
472 
473 	return 0;
474 }
475 
476 static int aaci_pcm_hw_free(struct snd_pcm_substream *substream)
477 {
478 	struct aaci_runtime *aacirun = substream->runtime->private_data;
479 
480 	/*
481 	 * This must not be called with the device enabled.
482 	 */
483 	WARN_ON(aacirun->cr & CR_EN);
484 
485 	if (aacirun->pcm_open)
486 		snd_ac97_pcm_close(aacirun->pcm);
487 	aacirun->pcm_open = 0;
488 
489 	/*
490 	 * Clear out the DMA and any allocated buffers.
491 	 */
492 	snd_pcm_lib_free_pages(substream);
493 
494 	return 0;
495 }
496 
497 /* Channel to slot mask */
498 static const u32 channels_to_slotmask[] = {
499 	[2] = CR_SL3 | CR_SL4,
500 	[4] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8,
501 	[6] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8 | CR_SL6 | CR_SL9,
502 };
503 
504 static int aaci_pcm_hw_params(struct snd_pcm_substream *substream,
505 			      struct snd_pcm_hw_params *params)
506 {
507 	struct aaci_runtime *aacirun = substream->runtime->private_data;
508 	unsigned int channels = params_channels(params);
509 	unsigned int rate = params_rate(params);
510 	int dbl = rate > 48000;
511 	int err;
512 
513 	aaci_pcm_hw_free(substream);
514 	if (aacirun->pcm_open) {
515 		snd_ac97_pcm_close(aacirun->pcm);
516 		aacirun->pcm_open = 0;
517 	}
518 
519 	/* channels is already limited to 2, 4, or 6 by aaci_rule_channels */
520 	if (dbl && channels != 2)
521 		return -EINVAL;
522 
523 	err = snd_pcm_lib_malloc_pages(substream,
524 				       params_buffer_bytes(params));
525 	if (err >= 0) {
526 		struct aaci *aaci = substream->private_data;
527 
528 		err = snd_ac97_pcm_open(aacirun->pcm, rate, channels,
529 					aacirun->pcm->r[dbl].slots);
530 
531 		aacirun->pcm_open = err == 0;
532 		aacirun->cr = CR_FEN | CR_COMPACT | CR_SZ16;
533 		aacirun->cr |= channels_to_slotmask[channels + dbl * 2];
534 
535 		/*
536 		 * fifo_bytes is the number of bytes we transfer to/from
537 		 * the FIFO, including padding.  So that's x4.  As we're
538 		 * in compact mode, the FIFO is half the size.
539 		 */
540 		aacirun->fifo_bytes = aaci->fifo_depth * 4 / 2;
541 	}
542 
543 	return err;
544 }
545 
546 static int aaci_pcm_prepare(struct snd_pcm_substream *substream)
547 {
548 	struct snd_pcm_runtime *runtime = substream->runtime;
549 	struct aaci_runtime *aacirun = runtime->private_data;
550 
551 	aacirun->period	= snd_pcm_lib_period_bytes(substream);
552 	aacirun->start	= runtime->dma_area;
553 	aacirun->end	= aacirun->start + snd_pcm_lib_buffer_bytes(substream);
554 	aacirun->ptr	= aacirun->start;
555 	aacirun->bytes	= aacirun->period;
556 
557 	return 0;
558 }
559 
560 static snd_pcm_uframes_t aaci_pcm_pointer(struct snd_pcm_substream *substream)
561 {
562 	struct snd_pcm_runtime *runtime = substream->runtime;
563 	struct aaci_runtime *aacirun = runtime->private_data;
564 	ssize_t bytes = aacirun->ptr - aacirun->start;
565 
566 	return bytes_to_frames(runtime, bytes);
567 }
568 
569 
570 /*
571  * Playback specific ALSA stuff
572  */
573 static void aaci_pcm_playback_stop(struct aaci_runtime *aacirun)
574 {
575 	u32 ie;
576 
577 	ie = readl(aacirun->base + AACI_IE);
578 	ie &= ~(IE_URIE|IE_TXIE);
579 	writel(ie, aacirun->base + AACI_IE);
580 	aacirun->cr &= ~CR_EN;
581 	aaci_chan_wait_ready(aacirun, SR_TXB);
582 	writel(aacirun->cr, aacirun->base + AACI_TXCR);
583 }
584 
585 static void aaci_pcm_playback_start(struct aaci_runtime *aacirun)
586 {
587 	u32 ie;
588 
589 	aaci_chan_wait_ready(aacirun, SR_TXB);
590 	aacirun->cr |= CR_EN;
591 
592 	ie = readl(aacirun->base + AACI_IE);
593 	ie |= IE_URIE | IE_TXIE;
594 	writel(ie, aacirun->base + AACI_IE);
595 	writel(aacirun->cr, aacirun->base + AACI_TXCR);
596 }
597 
598 static int aaci_pcm_playback_trigger(struct snd_pcm_substream *substream, int cmd)
599 {
600 	struct aaci_runtime *aacirun = substream->runtime->private_data;
601 	unsigned long flags;
602 	int ret = 0;
603 
604 	spin_lock_irqsave(&aacirun->lock, flags);
605 
606 	switch (cmd) {
607 	case SNDRV_PCM_TRIGGER_START:
608 		aaci_pcm_playback_start(aacirun);
609 		break;
610 
611 	case SNDRV_PCM_TRIGGER_RESUME:
612 		aaci_pcm_playback_start(aacirun);
613 		break;
614 
615 	case SNDRV_PCM_TRIGGER_STOP:
616 		aaci_pcm_playback_stop(aacirun);
617 		break;
618 
619 	case SNDRV_PCM_TRIGGER_SUSPEND:
620 		aaci_pcm_playback_stop(aacirun);
621 		break;
622 
623 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
624 		break;
625 
626 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
627 		break;
628 
629 	default:
630 		ret = -EINVAL;
631 	}
632 
633 	spin_unlock_irqrestore(&aacirun->lock, flags);
634 
635 	return ret;
636 }
637 
638 static const struct snd_pcm_ops aaci_playback_ops = {
639 	.open		= aaci_pcm_open,
640 	.close		= aaci_pcm_close,
641 	.ioctl		= snd_pcm_lib_ioctl,
642 	.hw_params	= aaci_pcm_hw_params,
643 	.hw_free	= aaci_pcm_hw_free,
644 	.prepare	= aaci_pcm_prepare,
645 	.trigger	= aaci_pcm_playback_trigger,
646 	.pointer	= aaci_pcm_pointer,
647 };
648 
649 static void aaci_pcm_capture_stop(struct aaci_runtime *aacirun)
650 {
651 	u32 ie;
652 
653 	aaci_chan_wait_ready(aacirun, SR_RXB);
654 
655 	ie = readl(aacirun->base + AACI_IE);
656 	ie &= ~(IE_ORIE | IE_RXIE);
657 	writel(ie, aacirun->base+AACI_IE);
658 
659 	aacirun->cr &= ~CR_EN;
660 
661 	writel(aacirun->cr, aacirun->base + AACI_RXCR);
662 }
663 
664 static void aaci_pcm_capture_start(struct aaci_runtime *aacirun)
665 {
666 	u32 ie;
667 
668 	aaci_chan_wait_ready(aacirun, SR_RXB);
669 
670 #ifdef DEBUG
671 	/* RX Timeout value: bits 28:17 in RXCR */
672 	aacirun->cr |= 0xf << 17;
673 #endif
674 
675 	aacirun->cr |= CR_EN;
676 	writel(aacirun->cr, aacirun->base + AACI_RXCR);
677 
678 	ie = readl(aacirun->base + AACI_IE);
679 	ie |= IE_ORIE |IE_RXIE; // overrun and rx interrupt -- half full
680 	writel(ie, aacirun->base + AACI_IE);
681 }
682 
683 static int aaci_pcm_capture_trigger(struct snd_pcm_substream *substream, int cmd)
684 {
685 	struct aaci_runtime *aacirun = substream->runtime->private_data;
686 	unsigned long flags;
687 	int ret = 0;
688 
689 	spin_lock_irqsave(&aacirun->lock, flags);
690 
691 	switch (cmd) {
692 	case SNDRV_PCM_TRIGGER_START:
693 		aaci_pcm_capture_start(aacirun);
694 		break;
695 
696 	case SNDRV_PCM_TRIGGER_RESUME:
697 		aaci_pcm_capture_start(aacirun);
698 		break;
699 
700 	case SNDRV_PCM_TRIGGER_STOP:
701 		aaci_pcm_capture_stop(aacirun);
702 		break;
703 
704 	case SNDRV_PCM_TRIGGER_SUSPEND:
705 		aaci_pcm_capture_stop(aacirun);
706 		break;
707 
708 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
709 		break;
710 
711 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
712 		break;
713 
714 	default:
715 		ret = -EINVAL;
716 	}
717 
718 	spin_unlock_irqrestore(&aacirun->lock, flags);
719 
720 	return ret;
721 }
722 
723 static int aaci_pcm_capture_prepare(struct snd_pcm_substream *substream)
724 {
725 	struct snd_pcm_runtime *runtime = substream->runtime;
726 	struct aaci *aaci = substream->private_data;
727 
728 	aaci_pcm_prepare(substream);
729 
730 	/* allow changing of sample rate */
731 	aaci_ac97_write(aaci->ac97, AC97_EXTENDED_STATUS, 0x0001); /* VRA */
732 	aaci_ac97_write(aaci->ac97, AC97_PCM_LR_ADC_RATE, runtime->rate);
733 	aaci_ac97_write(aaci->ac97, AC97_PCM_MIC_ADC_RATE, runtime->rate);
734 
735 	/* Record select: Mic: 0, Aux: 3, Line: 4 */
736 	aaci_ac97_write(aaci->ac97, AC97_REC_SEL, 0x0404);
737 
738 	return 0;
739 }
740 
741 static const struct snd_pcm_ops aaci_capture_ops = {
742 	.open		= aaci_pcm_open,
743 	.close		= aaci_pcm_close,
744 	.ioctl		= snd_pcm_lib_ioctl,
745 	.hw_params	= aaci_pcm_hw_params,
746 	.hw_free	= aaci_pcm_hw_free,
747 	.prepare	= aaci_pcm_capture_prepare,
748 	.trigger	= aaci_pcm_capture_trigger,
749 	.pointer	= aaci_pcm_pointer,
750 };
751 
752 /*
753  * Power Management.
754  */
755 #ifdef CONFIG_PM
756 static int aaci_do_suspend(struct snd_card *card)
757 {
758 	struct aaci *aaci = card->private_data;
759 	snd_power_change_state(card, SNDRV_CTL_POWER_D3cold);
760 	return 0;
761 }
762 
763 static int aaci_do_resume(struct snd_card *card)
764 {
765 	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
766 	return 0;
767 }
768 
769 static int aaci_suspend(struct device *dev)
770 {
771 	struct snd_card *card = dev_get_drvdata(dev);
772 	return card ? aaci_do_suspend(card) : 0;
773 }
774 
775 static int aaci_resume(struct device *dev)
776 {
777 	struct snd_card *card = dev_get_drvdata(dev);
778 	return card ? aaci_do_resume(card) : 0;
779 }
780 
781 static SIMPLE_DEV_PM_OPS(aaci_dev_pm_ops, aaci_suspend, aaci_resume);
782 #define AACI_DEV_PM_OPS (&aaci_dev_pm_ops)
783 #else
784 #define AACI_DEV_PM_OPS NULL
785 #endif
786 
787 
788 static const struct ac97_pcm ac97_defs[] = {
789 	[0] = {	/* Front PCM */
790 		.exclusive = 1,
791 		.r = {
792 			[0] = {
793 				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
794 					  (1 << AC97_SLOT_PCM_RIGHT) |
795 					  (1 << AC97_SLOT_PCM_CENTER) |
796 					  (1 << AC97_SLOT_PCM_SLEFT) |
797 					  (1 << AC97_SLOT_PCM_SRIGHT) |
798 					  (1 << AC97_SLOT_LFE),
799 			},
800 			[1] = {
801 				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
802 					  (1 << AC97_SLOT_PCM_RIGHT) |
803 					  (1 << AC97_SLOT_PCM_LEFT_0) |
804 					  (1 << AC97_SLOT_PCM_RIGHT_0),
805 			},
806 		},
807 	},
808 	[1] = {	/* PCM in */
809 		.stream = 1,
810 		.exclusive = 1,
811 		.r = {
812 			[0] = {
813 				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
814 					  (1 << AC97_SLOT_PCM_RIGHT),
815 			},
816 		},
817 	},
818 	[2] = {	/* Mic in */
819 		.stream = 1,
820 		.exclusive = 1,
821 		.r = {
822 			[0] = {
823 				.slots	= (1 << AC97_SLOT_MIC),
824 			},
825 		},
826 	}
827 };
828 
829 static struct snd_ac97_bus_ops aaci_bus_ops = {
830 	.write	= aaci_ac97_write,
831 	.read	= aaci_ac97_read,
832 };
833 
834 static int aaci_probe_ac97(struct aaci *aaci)
835 {
836 	struct snd_ac97_template ac97_template;
837 	struct snd_ac97_bus *ac97_bus;
838 	struct snd_ac97 *ac97;
839 	int ret;
840 
841 	/*
842 	 * Assert AACIRESET for 2us
843 	 */
844 	writel(0, aaci->base + AACI_RESET);
845 	udelay(2);
846 	writel(RESET_NRST, aaci->base + AACI_RESET);
847 
848 	/*
849 	 * Give the AC'97 codec more than enough time
850 	 * to wake up. (42us = ~2 frames at 48kHz.)
851 	 */
852 	udelay(FRAME_PERIOD_US * 2);
853 
854 	ret = snd_ac97_bus(aaci->card, 0, &aaci_bus_ops, aaci, &ac97_bus);
855 	if (ret)
856 		goto out;
857 
858 	ac97_bus->clock = 48000;
859 	aaci->ac97_bus = ac97_bus;
860 
861 	memset(&ac97_template, 0, sizeof(struct snd_ac97_template));
862 	ac97_template.private_data = aaci;
863 	ac97_template.num = 0;
864 	ac97_template.scaps = AC97_SCAP_SKIP_MODEM;
865 
866 	ret = snd_ac97_mixer(ac97_bus, &ac97_template, &ac97);
867 	if (ret)
868 		goto out;
869 	aaci->ac97 = ac97;
870 
871 	/*
872 	 * Disable AC97 PC Beep input on audio codecs.
873 	 */
874 	if (ac97_is_audio(ac97))
875 		snd_ac97_write_cache(ac97, AC97_PC_BEEP, 0x801e);
876 
877 	ret = snd_ac97_pcm_assign(ac97_bus, ARRAY_SIZE(ac97_defs), ac97_defs);
878 	if (ret)
879 		goto out;
880 
881 	aaci->playback.pcm = &ac97_bus->pcms[0];
882 	aaci->capture.pcm  = &ac97_bus->pcms[1];
883 
884  out:
885 	return ret;
886 }
887 
888 static void aaci_free_card(struct snd_card *card)
889 {
890 	struct aaci *aaci = card->private_data;
891 
892 	iounmap(aaci->base);
893 }
894 
895 static struct aaci *aaci_init_card(struct amba_device *dev)
896 {
897 	struct aaci *aaci;
898 	struct snd_card *card;
899 	int err;
900 
901 	err = snd_card_new(&dev->dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
902 			   THIS_MODULE, sizeof(struct aaci), &card);
903 	if (err < 0)
904 		return NULL;
905 
906 	card->private_free = aaci_free_card;
907 
908 	strlcpy(card->driver, DRIVER_NAME, sizeof(card->driver));
909 	strlcpy(card->shortname, "ARM AC'97 Interface", sizeof(card->shortname));
910 	snprintf(card->longname, sizeof(card->longname),
911 		 "%s PL%03x rev%u at 0x%08llx, irq %d",
912 		 card->shortname, amba_part(dev), amba_rev(dev),
913 		 (unsigned long long)dev->res.start, dev->irq[0]);
914 
915 	aaci = card->private_data;
916 	mutex_init(&aaci->ac97_sem);
917 	mutex_init(&aaci->irq_lock);
918 	aaci->card = card;
919 	aaci->dev = dev;
920 
921 	/* Set MAINCR to allow slot 1 and 2 data IO */
922 	aaci->maincr = MAINCR_IE | MAINCR_SL1RXEN | MAINCR_SL1TXEN |
923 		       MAINCR_SL2RXEN | MAINCR_SL2TXEN;
924 
925 	return aaci;
926 }
927 
928 static int aaci_init_pcm(struct aaci *aaci)
929 {
930 	struct snd_pcm *pcm;
931 	int ret;
932 
933 	ret = snd_pcm_new(aaci->card, "AACI AC'97", 0, 1, 1, &pcm);
934 	if (ret == 0) {
935 		aaci->pcm = pcm;
936 		pcm->private_data = aaci;
937 		pcm->info_flags = 0;
938 
939 		strlcpy(pcm->name, DRIVER_NAME, sizeof(pcm->name));
940 
941 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &aaci_playback_ops);
942 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &aaci_capture_ops);
943 		snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
944 						      aaci->card->dev,
945 						      0, 64 * 1024);
946 	}
947 
948 	return ret;
949 }
950 
951 static unsigned int aaci_size_fifo(struct aaci *aaci)
952 {
953 	struct aaci_runtime *aacirun = &aaci->playback;
954 	int i;
955 
956 	/*
957 	 * Enable the channel, but don't assign it to any slots, so
958 	 * it won't empty onto the AC'97 link.
959 	 */
960 	writel(CR_FEN | CR_SZ16 | CR_EN, aacirun->base + AACI_TXCR);
961 
962 	for (i = 0; !(readl(aacirun->base + AACI_SR) & SR_TXFF) && i < 4096; i++)
963 		writel(0, aacirun->fifo);
964 
965 	writel(0, aacirun->base + AACI_TXCR);
966 
967 	/*
968 	 * Re-initialise the AACI after the FIFO depth test, to
969 	 * ensure that the FIFOs are empty.  Unfortunately, merely
970 	 * disabling the channel doesn't clear the FIFO.
971 	 */
972 	writel(aaci->maincr & ~MAINCR_IE, aaci->base + AACI_MAINCR);
973 	readl(aaci->base + AACI_MAINCR);
974 	udelay(1);
975 	writel(aaci->maincr, aaci->base + AACI_MAINCR);
976 
977 	/*
978 	 * If we hit 4096 entries, we failed.  Go back to the specified
979 	 * fifo depth.
980 	 */
981 	if (i == 4096)
982 		i = 8;
983 
984 	return i;
985 }
986 
987 static int aaci_probe(struct amba_device *dev,
988 		      const struct amba_id *id)
989 {
990 	struct aaci *aaci;
991 	int ret, i;
992 
993 	ret = amba_request_regions(dev, NULL);
994 	if (ret)
995 		return ret;
996 
997 	aaci = aaci_init_card(dev);
998 	if (!aaci) {
999 		ret = -ENOMEM;
1000 		goto out;
1001 	}
1002 
1003 	aaci->base = ioremap(dev->res.start, resource_size(&dev->res));
1004 	if (!aaci->base) {
1005 		ret = -ENOMEM;
1006 		goto out;
1007 	}
1008 
1009 	/*
1010 	 * Playback uses AACI channel 0
1011 	 */
1012 	spin_lock_init(&aaci->playback.lock);
1013 	aaci->playback.base = aaci->base + AACI_CSCH1;
1014 	aaci->playback.fifo = aaci->base + AACI_DR1;
1015 
1016 	/*
1017 	 * Capture uses AACI channel 0
1018 	 */
1019 	spin_lock_init(&aaci->capture.lock);
1020 	aaci->capture.base = aaci->base + AACI_CSCH1;
1021 	aaci->capture.fifo = aaci->base + AACI_DR1;
1022 
1023 	for (i = 0; i < 4; i++) {
1024 		void __iomem *base = aaci->base + i * 0x14;
1025 
1026 		writel(0, base + AACI_IE);
1027 		writel(0, base + AACI_TXCR);
1028 		writel(0, base + AACI_RXCR);
1029 	}
1030 
1031 	writel(0x1fff, aaci->base + AACI_INTCLR);
1032 	writel(aaci->maincr, aaci->base + AACI_MAINCR);
1033 	/*
1034 	 * Fix: ac97 read back fail errors by reading
1035 	 * from any arbitrary aaci register.
1036 	 */
1037 	readl(aaci->base + AACI_CSCH1);
1038 	ret = aaci_probe_ac97(aaci);
1039 	if (ret)
1040 		goto out;
1041 
1042 	/*
1043 	 * Size the FIFOs (must be multiple of 16).
1044 	 * This is the number of entries in the FIFO.
1045 	 */
1046 	aaci->fifo_depth = aaci_size_fifo(aaci);
1047 	if (aaci->fifo_depth & 15) {
1048 		printk(KERN_WARNING "AACI: FIFO depth %d not supported\n",
1049 		       aaci->fifo_depth);
1050 		ret = -ENODEV;
1051 		goto out;
1052 	}
1053 
1054 	ret = aaci_init_pcm(aaci);
1055 	if (ret)
1056 		goto out;
1057 
1058 	ret = snd_card_register(aaci->card);
1059 	if (ret == 0) {
1060 		dev_info(&dev->dev, "%s\n", aaci->card->longname);
1061 		dev_info(&dev->dev, "FIFO %u entries\n", aaci->fifo_depth);
1062 		amba_set_drvdata(dev, aaci->card);
1063 		return ret;
1064 	}
1065 
1066  out:
1067 	if (aaci)
1068 		snd_card_free(aaci->card);
1069 	amba_release_regions(dev);
1070 	return ret;
1071 }
1072 
1073 static int aaci_remove(struct amba_device *dev)
1074 {
1075 	struct snd_card *card = amba_get_drvdata(dev);
1076 
1077 	if (card) {
1078 		struct aaci *aaci = card->private_data;
1079 		writel(0, aaci->base + AACI_MAINCR);
1080 
1081 		snd_card_free(card);
1082 		amba_release_regions(dev);
1083 	}
1084 
1085 	return 0;
1086 }
1087 
1088 static struct amba_id aaci_ids[] = {
1089 	{
1090 		.id	= 0x00041041,
1091 		.mask	= 0x000fffff,
1092 	},
1093 	{ 0, 0 },
1094 };
1095 
1096 MODULE_DEVICE_TABLE(amba, aaci_ids);
1097 
1098 static struct amba_driver aaci_driver = {
1099 	.drv		= {
1100 		.name	= DRIVER_NAME,
1101 		.pm	= AACI_DEV_PM_OPS,
1102 	},
1103 	.probe		= aaci_probe,
1104 	.remove		= aaci_remove,
1105 	.id_table	= aaci_ids,
1106 };
1107 
1108 module_amba_driver(aaci_driver);
1109 
1110 MODULE_LICENSE("GPL");
1111 MODULE_DESCRIPTION("ARM PrimeCell PL041 Advanced Audio CODEC Interface driver");
1112