xref: /openbmc/linux/sound/arm/aaci.c (revision 4800cd83)
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 		void *ptr;
214 
215 		if (!aacirun->substream || !aacirun->start) {
216 			dev_warn(&aaci->dev->dev, "RX interrupt???\n");
217 			writel(0, aacirun->base + AACI_IE);
218 			return;
219 		}
220 
221 		spin_lock(&aacirun->lock);
222 
223 		ptr = aacirun->ptr;
224 		do {
225 			unsigned int len = aacirun->fifosz;
226 			u32 val;
227 
228 			if (aacirun->bytes <= 0) {
229 				aacirun->bytes += aacirun->period;
230 				aacirun->ptr = ptr;
231 				spin_unlock(&aacirun->lock);
232 				snd_pcm_period_elapsed(aacirun->substream);
233 				spin_lock(&aacirun->lock);
234 			}
235 			if (!(aacirun->cr & CR_EN))
236 				break;
237 
238 			val = readl(aacirun->base + AACI_SR);
239 			if (!(val & SR_RXHF))
240 				break;
241 			if (!(val & SR_RXFF))
242 				len >>= 1;
243 
244 			aacirun->bytes -= len;
245 
246 			/* reading 16 bytes at a time */
247 			for( ; len > 0; len -= 16) {
248 				asm(
249 					"ldmia	%1, {r0, r1, r2, r3}\n\t"
250 					"stmia	%0!, {r0, r1, r2, r3}"
251 					: "+r" (ptr)
252 					: "r" (aacirun->fifo)
253 					: "r0", "r1", "r2", "r3", "cc");
254 
255 				if (ptr >= aacirun->end)
256 					ptr = aacirun->start;
257 			}
258 		} while(1);
259 
260 		aacirun->ptr = ptr;
261 
262 		spin_unlock(&aacirun->lock);
263 	}
264 
265 	if (mask & ISR_URINTR) {
266 		dev_dbg(&aaci->dev->dev, "TX underrun on chan %d\n", channel);
267 		writel(ICLR_TXUEC1 << channel, aaci->base + AACI_INTCLR);
268 	}
269 
270 	if (mask & ISR_TXINTR) {
271 		struct aaci_runtime *aacirun = &aaci->playback;
272 		void *ptr;
273 
274 		if (!aacirun->substream || !aacirun->start) {
275 			dev_warn(&aaci->dev->dev, "TX interrupt???\n");
276 			writel(0, aacirun->base + AACI_IE);
277 			return;
278 		}
279 
280 		spin_lock(&aacirun->lock);
281 
282 		ptr = aacirun->ptr;
283 		do {
284 			unsigned int len = aacirun->fifosz;
285 			u32 val;
286 
287 			if (aacirun->bytes <= 0) {
288 				aacirun->bytes += aacirun->period;
289 				aacirun->ptr = ptr;
290 				spin_unlock(&aacirun->lock);
291 				snd_pcm_period_elapsed(aacirun->substream);
292 				spin_lock(&aacirun->lock);
293 			}
294 			if (!(aacirun->cr & CR_EN))
295 				break;
296 
297 			val = readl(aacirun->base + AACI_SR);
298 			if (!(val & SR_TXHE))
299 				break;
300 			if (!(val & SR_TXFE))
301 				len >>= 1;
302 
303 			aacirun->bytes -= len;
304 
305 			/* writing 16 bytes at a time */
306 			for ( ; len > 0; len -= 16) {
307 				asm(
308 					"ldmia	%0!, {r0, r1, r2, r3}\n\t"
309 					"stmia	%1, {r0, r1, r2, r3}"
310 					: "+r" (ptr)
311 					: "r" (aacirun->fifo)
312 					: "r0", "r1", "r2", "r3", "cc");
313 
314 				if (ptr >= aacirun->end)
315 					ptr = aacirun->start;
316 			}
317 		} while (1);
318 
319 		aacirun->ptr = ptr;
320 
321 		spin_unlock(&aacirun->lock);
322 	}
323 }
324 
325 static irqreturn_t aaci_irq(int irq, void *devid)
326 {
327 	struct aaci *aaci = devid;
328 	u32 mask;
329 	int i;
330 
331 	mask = readl(aaci->base + AACI_ALLINTS);
332 	if (mask) {
333 		u32 m = mask;
334 		for (i = 0; i < 4; i++, m >>= 7) {
335 			if (m & 0x7f) {
336 				aaci_fifo_irq(aaci, i, m);
337 			}
338 		}
339 	}
340 
341 	return mask ? IRQ_HANDLED : IRQ_NONE;
342 }
343 
344 
345 
346 /*
347  * ALSA support.
348  */
349 static struct snd_pcm_hardware aaci_hw_info = {
350 	.info			= SNDRV_PCM_INFO_MMAP |
351 				  SNDRV_PCM_INFO_MMAP_VALID |
352 				  SNDRV_PCM_INFO_INTERLEAVED |
353 				  SNDRV_PCM_INFO_BLOCK_TRANSFER |
354 				  SNDRV_PCM_INFO_RESUME,
355 
356 	/*
357 	 * ALSA doesn't support 18-bit or 20-bit packed into 32-bit
358 	 * words.  It also doesn't support 12-bit at all.
359 	 */
360 	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
361 
362 	/* rates are setup from the AC'97 codec */
363 	.channels_min		= 2,
364 	.channels_max		= 6,
365 	.buffer_bytes_max	= 64 * 1024,
366 	.period_bytes_min	= 256,
367 	.period_bytes_max	= PAGE_SIZE,
368 	.periods_min		= 4,
369 	.periods_max		= PAGE_SIZE / 16,
370 };
371 
372 static int __aaci_pcm_open(struct aaci *aaci,
373 			   struct snd_pcm_substream *substream,
374 			   struct aaci_runtime *aacirun)
375 {
376 	struct snd_pcm_runtime *runtime = substream->runtime;
377 	int ret;
378 
379 	aacirun->substream = substream;
380 	runtime->private_data = aacirun;
381 	runtime->hw = aaci_hw_info;
382 	runtime->hw.rates = aacirun->pcm->rates;
383 	snd_pcm_limit_hw_rates(runtime);
384 
385 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
386 	    aacirun->pcm->r[1].slots)
387 		snd_ac97_pcm_double_rate_rules(runtime);
388 
389 	/*
390 	 * FIXME: ALSA specifies fifo_size in bytes.  If we're in normal
391 	 * mode, each 32-bit word contains one sample.  If we're in
392 	 * compact mode, each 32-bit word contains two samples, effectively
393 	 * halving the FIFO size.  However, we don't know for sure which
394 	 * we'll be using at this point.  We set this to the lower limit.
395 	 */
396 	runtime->hw.fifo_size = aaci->fifosize * 2;
397 
398 	ret = request_irq(aaci->dev->irq[0], aaci_irq, IRQF_SHARED|IRQF_DISABLED,
399 			  DRIVER_NAME, aaci);
400 	if (ret)
401 		goto out;
402 
403 	return 0;
404 
405  out:
406 	return ret;
407 }
408 
409 
410 /*
411  * Common ALSA stuff
412  */
413 static int aaci_pcm_close(struct snd_pcm_substream *substream)
414 {
415 	struct aaci *aaci = substream->private_data;
416 	struct aaci_runtime *aacirun = substream->runtime->private_data;
417 
418 	WARN_ON(aacirun->cr & CR_EN);
419 
420 	aacirun->substream = NULL;
421 	free_irq(aaci->dev->irq[0], aaci);
422 
423 	return 0;
424 }
425 
426 static int aaci_pcm_hw_free(struct snd_pcm_substream *substream)
427 {
428 	struct aaci_runtime *aacirun = substream->runtime->private_data;
429 
430 	/*
431 	 * This must not be called with the device enabled.
432 	 */
433 	WARN_ON(aacirun->cr & CR_EN);
434 
435 	if (aacirun->pcm_open)
436 		snd_ac97_pcm_close(aacirun->pcm);
437 	aacirun->pcm_open = 0;
438 
439 	/*
440 	 * Clear out the DMA and any allocated buffers.
441 	 */
442 	snd_pcm_lib_free_pages(substream);
443 
444 	return 0;
445 }
446 
447 static int aaci_pcm_hw_params(struct snd_pcm_substream *substream,
448 			      struct aaci_runtime *aacirun,
449 			      struct snd_pcm_hw_params *params)
450 {
451 	int err;
452 	struct aaci *aaci = substream->private_data;
453 
454 	aaci_pcm_hw_free(substream);
455 	if (aacirun->pcm_open) {
456 		snd_ac97_pcm_close(aacirun->pcm);
457 		aacirun->pcm_open = 0;
458 	}
459 
460 	err = snd_pcm_lib_malloc_pages(substream,
461 				       params_buffer_bytes(params));
462 	if (err >= 0) {
463 		unsigned int rate = params_rate(params);
464 		int dbl = rate > 48000;
465 
466 		err = snd_ac97_pcm_open(aacirun->pcm, rate,
467 					params_channels(params),
468 					aacirun->pcm->r[dbl].slots);
469 
470 		aacirun->pcm_open = err == 0;
471 		aacirun->cr = CR_FEN | CR_COMPACT | CR_SZ16;
472 		aacirun->fifosz = aaci->fifosize * 4;
473 
474 		if (aacirun->cr & CR_COMPACT)
475 			aacirun->fifosz >>= 1;
476 	}
477 
478 	return err;
479 }
480 
481 static int aaci_pcm_prepare(struct snd_pcm_substream *substream)
482 {
483 	struct snd_pcm_runtime *runtime = substream->runtime;
484 	struct aaci_runtime *aacirun = runtime->private_data;
485 
486 	aacirun->start	= runtime->dma_area;
487 	aacirun->end	= aacirun->start + snd_pcm_lib_buffer_bytes(substream);
488 	aacirun->ptr	= aacirun->start;
489 	aacirun->period	=
490 	aacirun->bytes	= frames_to_bytes(runtime, runtime->period_size);
491 
492 	return 0;
493 }
494 
495 static snd_pcm_uframes_t aaci_pcm_pointer(struct snd_pcm_substream *substream)
496 {
497 	struct snd_pcm_runtime *runtime = substream->runtime;
498 	struct aaci_runtime *aacirun = runtime->private_data;
499 	ssize_t bytes = aacirun->ptr - aacirun->start;
500 
501 	return bytes_to_frames(runtime, bytes);
502 }
503 
504 
505 /*
506  * Playback specific ALSA stuff
507  */
508 static const u32 channels_to_txmask[] = {
509 	[2] = CR_SL3 | CR_SL4,
510 	[4] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8,
511 	[6] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8 | CR_SL6 | CR_SL9,
512 };
513 
514 /*
515  * We can support two and four channel audio.  Unfortunately
516  * six channel audio requires a non-standard channel ordering:
517  *   2 -> FL(3), FR(4)
518  *   4 -> FL(3), FR(4), SL(7), SR(8)
519  *   6 -> FL(3), FR(4), SL(7), SR(8), C(6), LFE(9) (required)
520  *        FL(3), FR(4), C(6), SL(7), SR(8), LFE(9) (actual)
521  * This requires an ALSA configuration file to correct.
522  */
523 static unsigned int channel_list[] = { 2, 4, 6 };
524 
525 static int
526 aaci_rule_channels(struct snd_pcm_hw_params *p, struct snd_pcm_hw_rule *rule)
527 {
528 	struct aaci *aaci = rule->private;
529 	unsigned int chan_mask = 1 << 0, slots;
530 
531 	/*
532 	 * pcms[0] is the our 5.1 PCM instance.
533 	 */
534 	slots = aaci->ac97_bus->pcms[0].r[0].slots;
535 	if (slots & (1 << AC97_SLOT_PCM_SLEFT)) {
536 		chan_mask |= 1 << 1;
537 		if (slots & (1 << AC97_SLOT_LFE))
538 			chan_mask |= 1 << 2;
539 	}
540 
541 	return snd_interval_list(hw_param_interval(p, rule->var),
542 				 ARRAY_SIZE(channel_list), channel_list,
543 				 chan_mask);
544 }
545 
546 static int aaci_pcm_open(struct snd_pcm_substream *substream)
547 {
548 	struct aaci *aaci = substream->private_data;
549 	int ret;
550 
551 	/*
552 	 * Add rule describing channel dependency.
553 	 */
554 	ret = snd_pcm_hw_rule_add(substream->runtime, 0,
555 				  SNDRV_PCM_HW_PARAM_CHANNELS,
556 				  aaci_rule_channels, aaci,
557 				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
558 	if (ret)
559 		return ret;
560 
561 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
562 		ret = __aaci_pcm_open(aaci, substream, &aaci->playback);
563 	} else {
564 		ret = __aaci_pcm_open(aaci, substream, &aaci->capture);
565 	}
566 	return ret;
567 }
568 
569 static int aaci_pcm_playback_hw_params(struct snd_pcm_substream *substream,
570 				       struct snd_pcm_hw_params *params)
571 {
572 	struct aaci_runtime *aacirun = substream->runtime->private_data;
573 	unsigned int channels = params_channels(params);
574 	int ret;
575 
576 	WARN_ON(channels >= ARRAY_SIZE(channels_to_txmask) ||
577 		!channels_to_txmask[channels]);
578 
579 	ret = aaci_pcm_hw_params(substream, aacirun, params);
580 
581 	/*
582 	 * Enable FIFO, compact mode, 16 bits per sample.
583 	 * FIXME: double rate slots?
584 	 */
585 	if (ret >= 0)
586 		aacirun->cr |= channels_to_txmask[channels];
587 
588 	return ret;
589 }
590 
591 static void aaci_pcm_playback_stop(struct aaci_runtime *aacirun)
592 {
593 	u32 ie;
594 
595 	ie = readl(aacirun->base + AACI_IE);
596 	ie &= ~(IE_URIE|IE_TXIE);
597 	writel(ie, aacirun->base + AACI_IE);
598 	aacirun->cr &= ~CR_EN;
599 	aaci_chan_wait_ready(aacirun, SR_TXB);
600 	writel(aacirun->cr, aacirun->base + AACI_TXCR);
601 }
602 
603 static void aaci_pcm_playback_start(struct aaci_runtime *aacirun)
604 {
605 	u32 ie;
606 
607 	aaci_chan_wait_ready(aacirun, SR_TXB);
608 	aacirun->cr |= CR_EN;
609 
610 	ie = readl(aacirun->base + AACI_IE);
611 	ie |= IE_URIE | IE_TXIE;
612 	writel(ie, aacirun->base + AACI_IE);
613 	writel(aacirun->cr, aacirun->base + AACI_TXCR);
614 }
615 
616 static int aaci_pcm_playback_trigger(struct snd_pcm_substream *substream, int cmd)
617 {
618 	struct aaci_runtime *aacirun = substream->runtime->private_data;
619 	unsigned long flags;
620 	int ret = 0;
621 
622 	spin_lock_irqsave(&aacirun->lock, flags);
623 
624 	switch (cmd) {
625 	case SNDRV_PCM_TRIGGER_START:
626 		aaci_pcm_playback_start(aacirun);
627 		break;
628 
629 	case SNDRV_PCM_TRIGGER_RESUME:
630 		aaci_pcm_playback_start(aacirun);
631 		break;
632 
633 	case SNDRV_PCM_TRIGGER_STOP:
634 		aaci_pcm_playback_stop(aacirun);
635 		break;
636 
637 	case SNDRV_PCM_TRIGGER_SUSPEND:
638 		aaci_pcm_playback_stop(aacirun);
639 		break;
640 
641 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
642 		break;
643 
644 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
645 		break;
646 
647 	default:
648 		ret = -EINVAL;
649 	}
650 
651 	spin_unlock_irqrestore(&aacirun->lock, flags);
652 
653 	return ret;
654 }
655 
656 static struct snd_pcm_ops aaci_playback_ops = {
657 	.open		= aaci_pcm_open,
658 	.close		= aaci_pcm_close,
659 	.ioctl		= snd_pcm_lib_ioctl,
660 	.hw_params	= aaci_pcm_playback_hw_params,
661 	.hw_free	= aaci_pcm_hw_free,
662 	.prepare	= aaci_pcm_prepare,
663 	.trigger	= aaci_pcm_playback_trigger,
664 	.pointer	= aaci_pcm_pointer,
665 };
666 
667 static int aaci_pcm_capture_hw_params(struct snd_pcm_substream *substream,
668 				      struct snd_pcm_hw_params *params)
669 {
670 	struct aaci_runtime *aacirun = substream->runtime->private_data;
671 	int ret;
672 
673 	ret = aaci_pcm_hw_params(substream, aacirun, params);
674 	if (ret >= 0)
675 		/* Line in record: slot 3 and 4 */
676 		aacirun->cr |= CR_SL3 | CR_SL4;
677 
678 	return ret;
679 }
680 
681 static void aaci_pcm_capture_stop(struct aaci_runtime *aacirun)
682 {
683 	u32 ie;
684 
685 	aaci_chan_wait_ready(aacirun, SR_RXB);
686 
687 	ie = readl(aacirun->base + AACI_IE);
688 	ie &= ~(IE_ORIE | IE_RXIE);
689 	writel(ie, aacirun->base+AACI_IE);
690 
691 	aacirun->cr &= ~CR_EN;
692 
693 	writel(aacirun->cr, aacirun->base + AACI_RXCR);
694 }
695 
696 static void aaci_pcm_capture_start(struct aaci_runtime *aacirun)
697 {
698 	u32 ie;
699 
700 	aaci_chan_wait_ready(aacirun, SR_RXB);
701 
702 #ifdef DEBUG
703 	/* RX Timeout value: bits 28:17 in RXCR */
704 	aacirun->cr |= 0xf << 17;
705 #endif
706 
707 	aacirun->cr |= CR_EN;
708 	writel(aacirun->cr, aacirun->base + AACI_RXCR);
709 
710 	ie = readl(aacirun->base + AACI_IE);
711 	ie |= IE_ORIE |IE_RXIE; // overrun and rx interrupt -- half full
712 	writel(ie, aacirun->base + AACI_IE);
713 }
714 
715 static int aaci_pcm_capture_trigger(struct snd_pcm_substream *substream, int cmd)
716 {
717 	struct aaci_runtime *aacirun = substream->runtime->private_data;
718 	unsigned long flags;
719 	int ret = 0;
720 
721 	spin_lock_irqsave(&aacirun->lock, flags);
722 
723 	switch (cmd) {
724 	case SNDRV_PCM_TRIGGER_START:
725 		aaci_pcm_capture_start(aacirun);
726 		break;
727 
728 	case SNDRV_PCM_TRIGGER_RESUME:
729 		aaci_pcm_capture_start(aacirun);
730 		break;
731 
732 	case SNDRV_PCM_TRIGGER_STOP:
733 		aaci_pcm_capture_stop(aacirun);
734 		break;
735 
736 	case SNDRV_PCM_TRIGGER_SUSPEND:
737 		aaci_pcm_capture_stop(aacirun);
738 		break;
739 
740 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
741 		break;
742 
743 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
744 		break;
745 
746 	default:
747 		ret = -EINVAL;
748 	}
749 
750 	spin_unlock_irqrestore(&aacirun->lock, flags);
751 
752 	return ret;
753 }
754 
755 static int aaci_pcm_capture_prepare(struct snd_pcm_substream *substream)
756 {
757 	struct snd_pcm_runtime *runtime = substream->runtime;
758 	struct aaci *aaci = substream->private_data;
759 
760 	aaci_pcm_prepare(substream);
761 
762 	/* allow changing of sample rate */
763 	aaci_ac97_write(aaci->ac97, AC97_EXTENDED_STATUS, 0x0001); /* VRA */
764 	aaci_ac97_write(aaci->ac97, AC97_PCM_LR_ADC_RATE, runtime->rate);
765 	aaci_ac97_write(aaci->ac97, AC97_PCM_MIC_ADC_RATE, runtime->rate);
766 
767 	/* Record select: Mic: 0, Aux: 3, Line: 4 */
768 	aaci_ac97_write(aaci->ac97, AC97_REC_SEL, 0x0404);
769 
770 	return 0;
771 }
772 
773 static struct snd_pcm_ops aaci_capture_ops = {
774 	.open		= aaci_pcm_open,
775 	.close		= aaci_pcm_close,
776 	.ioctl		= snd_pcm_lib_ioctl,
777 	.hw_params	= aaci_pcm_capture_hw_params,
778 	.hw_free	= aaci_pcm_hw_free,
779 	.prepare	= aaci_pcm_capture_prepare,
780 	.trigger	= aaci_pcm_capture_trigger,
781 	.pointer	= aaci_pcm_pointer,
782 };
783 
784 /*
785  * Power Management.
786  */
787 #ifdef CONFIG_PM
788 static int aaci_do_suspend(struct snd_card *card, unsigned int state)
789 {
790 	struct aaci *aaci = card->private_data;
791 	snd_power_change_state(card, SNDRV_CTL_POWER_D3cold);
792 	snd_pcm_suspend_all(aaci->pcm);
793 	return 0;
794 }
795 
796 static int aaci_do_resume(struct snd_card *card, unsigned int state)
797 {
798 	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
799 	return 0;
800 }
801 
802 static int aaci_suspend(struct amba_device *dev, pm_message_t state)
803 {
804 	struct snd_card *card = amba_get_drvdata(dev);
805 	return card ? aaci_do_suspend(card) : 0;
806 }
807 
808 static int aaci_resume(struct amba_device *dev)
809 {
810 	struct snd_card *card = amba_get_drvdata(dev);
811 	return card ? aaci_do_resume(card) : 0;
812 }
813 #else
814 #define aaci_do_suspend		NULL
815 #define aaci_do_resume		NULL
816 #define aaci_suspend		NULL
817 #define aaci_resume		NULL
818 #endif
819 
820 
821 static struct ac97_pcm ac97_defs[] __devinitdata = {
822 	[0] = {	/* Front PCM */
823 		.exclusive = 1,
824 		.r = {
825 			[0] = {
826 				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
827 					  (1 << AC97_SLOT_PCM_RIGHT) |
828 					  (1 << AC97_SLOT_PCM_CENTER) |
829 					  (1 << AC97_SLOT_PCM_SLEFT) |
830 					  (1 << AC97_SLOT_PCM_SRIGHT) |
831 					  (1 << AC97_SLOT_LFE),
832 			},
833 			[1] = {
834 				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
835 					  (1 << AC97_SLOT_PCM_RIGHT) |
836 					  (1 << AC97_SLOT_PCM_LEFT_0) |
837 					  (1 << AC97_SLOT_PCM_RIGHT_0),
838 			},
839 		},
840 	},
841 	[1] = {	/* PCM in */
842 		.stream = 1,
843 		.exclusive = 1,
844 		.r = {
845 			[0] = {
846 				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
847 					  (1 << AC97_SLOT_PCM_RIGHT),
848 			},
849 		},
850 	},
851 	[2] = {	/* Mic in */
852 		.stream = 1,
853 		.exclusive = 1,
854 		.r = {
855 			[0] = {
856 				.slots	= (1 << AC97_SLOT_MIC),
857 			},
858 		},
859 	}
860 };
861 
862 static struct snd_ac97_bus_ops aaci_bus_ops = {
863 	.write	= aaci_ac97_write,
864 	.read	= aaci_ac97_read,
865 };
866 
867 static int __devinit aaci_probe_ac97(struct aaci *aaci)
868 {
869 	struct snd_ac97_template ac97_template;
870 	struct snd_ac97_bus *ac97_bus;
871 	struct snd_ac97 *ac97;
872 	int ret;
873 
874 	/*
875 	 * Assert AACIRESET for 2us
876 	 */
877 	writel(0, aaci->base + AACI_RESET);
878 	udelay(2);
879 	writel(RESET_NRST, aaci->base + AACI_RESET);
880 
881 	/*
882 	 * Give the AC'97 codec more than enough time
883 	 * to wake up. (42us = ~2 frames at 48kHz.)
884 	 */
885 	udelay(FRAME_PERIOD_US * 2);
886 
887 	ret = snd_ac97_bus(aaci->card, 0, &aaci_bus_ops, aaci, &ac97_bus);
888 	if (ret)
889 		goto out;
890 
891 	ac97_bus->clock = 48000;
892 	aaci->ac97_bus = ac97_bus;
893 
894 	memset(&ac97_template, 0, sizeof(struct snd_ac97_template));
895 	ac97_template.private_data = aaci;
896 	ac97_template.num = 0;
897 	ac97_template.scaps = AC97_SCAP_SKIP_MODEM;
898 
899 	ret = snd_ac97_mixer(ac97_bus, &ac97_template, &ac97);
900 	if (ret)
901 		goto out;
902 	aaci->ac97 = ac97;
903 
904 	/*
905 	 * Disable AC97 PC Beep input on audio codecs.
906 	 */
907 	if (ac97_is_audio(ac97))
908 		snd_ac97_write_cache(ac97, AC97_PC_BEEP, 0x801e);
909 
910 	ret = snd_ac97_pcm_assign(ac97_bus, ARRAY_SIZE(ac97_defs), ac97_defs);
911 	if (ret)
912 		goto out;
913 
914 	aaci->playback.pcm = &ac97_bus->pcms[0];
915 	aaci->capture.pcm  = &ac97_bus->pcms[1];
916 
917  out:
918 	return ret;
919 }
920 
921 static void aaci_free_card(struct snd_card *card)
922 {
923 	struct aaci *aaci = card->private_data;
924 	if (aaci->base)
925 		iounmap(aaci->base);
926 }
927 
928 static struct aaci * __devinit aaci_init_card(struct amba_device *dev)
929 {
930 	struct aaci *aaci;
931 	struct snd_card *card;
932 	int err;
933 
934 	err = snd_card_create(SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
935 			      THIS_MODULE, sizeof(struct aaci), &card);
936 	if (err < 0)
937 		return NULL;
938 
939 	card->private_free = aaci_free_card;
940 
941 	strlcpy(card->driver, DRIVER_NAME, sizeof(card->driver));
942 	strlcpy(card->shortname, "ARM AC'97 Interface", sizeof(card->shortname));
943 	snprintf(card->longname, sizeof(card->longname),
944 		 "%s at 0x%016llx, irq %d",
945 		 card->shortname, (unsigned long long)dev->res.start,
946 		 dev->irq[0]);
947 
948 	aaci = card->private_data;
949 	mutex_init(&aaci->ac97_sem);
950 	aaci->card = card;
951 	aaci->dev = dev;
952 
953 	/* Set MAINCR to allow slot 1 and 2 data IO */
954 	aaci->maincr = MAINCR_IE | MAINCR_SL1RXEN | MAINCR_SL1TXEN |
955 		       MAINCR_SL2RXEN | MAINCR_SL2TXEN;
956 
957 	return aaci;
958 }
959 
960 static int __devinit aaci_init_pcm(struct aaci *aaci)
961 {
962 	struct snd_pcm *pcm;
963 	int ret;
964 
965 	ret = snd_pcm_new(aaci->card, "AACI AC'97", 0, 1, 1, &pcm);
966 	if (ret == 0) {
967 		aaci->pcm = pcm;
968 		pcm->private_data = aaci;
969 		pcm->info_flags = 0;
970 
971 		strlcpy(pcm->name, DRIVER_NAME, sizeof(pcm->name));
972 
973 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &aaci_playback_ops);
974 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &aaci_capture_ops);
975 		snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
976 						      NULL, 0, 64 * 1024);
977 	}
978 
979 	return ret;
980 }
981 
982 static unsigned int __devinit aaci_size_fifo(struct aaci *aaci)
983 {
984 	struct aaci_runtime *aacirun = &aaci->playback;
985 	int i;
986 
987 	writel(CR_FEN | CR_SZ16 | CR_EN, aacirun->base + AACI_TXCR);
988 
989 	for (i = 0; !(readl(aacirun->base + AACI_SR) & SR_TXFF) && i < 4096; i++)
990 		writel(0, aacirun->fifo);
991 
992 	writel(0, aacirun->base + AACI_TXCR);
993 
994 	/*
995 	 * Re-initialise the AACI after the FIFO depth test, to
996 	 * ensure that the FIFOs are empty.  Unfortunately, merely
997 	 * disabling the channel doesn't clear the FIFO.
998 	 */
999 	writel(aaci->maincr & ~MAINCR_IE, aaci->base + AACI_MAINCR);
1000 	readl(aaci->base + AACI_MAINCR);
1001 	udelay(1);
1002 	writel(aaci->maincr, aaci->base + AACI_MAINCR);
1003 
1004 	/*
1005 	 * If we hit 4096, we failed.  Go back to the specified
1006 	 * fifo depth.
1007 	 */
1008 	if (i == 4096)
1009 		i = 8;
1010 
1011 	return i;
1012 }
1013 
1014 static int __devinit aaci_probe(struct amba_device *dev, struct amba_id *id)
1015 {
1016 	struct aaci *aaci;
1017 	int ret, i;
1018 
1019 	ret = amba_request_regions(dev, NULL);
1020 	if (ret)
1021 		return ret;
1022 
1023 	aaci = aaci_init_card(dev);
1024 	if (!aaci) {
1025 		ret = -ENOMEM;
1026 		goto out;
1027 	}
1028 
1029 	aaci->base = ioremap(dev->res.start, resource_size(&dev->res));
1030 	if (!aaci->base) {
1031 		ret = -ENOMEM;
1032 		goto out;
1033 	}
1034 
1035 	/*
1036 	 * Playback uses AACI channel 0
1037 	 */
1038 	spin_lock_init(&aaci->playback.lock);
1039 	aaci->playback.base = aaci->base + AACI_CSCH1;
1040 	aaci->playback.fifo = aaci->base + AACI_DR1;
1041 
1042 	/*
1043 	 * Capture uses AACI channel 0
1044 	 */
1045 	spin_lock_init(&aaci->capture.lock);
1046 	aaci->capture.base = aaci->base + AACI_CSCH1;
1047 	aaci->capture.fifo = aaci->base + AACI_DR1;
1048 
1049 	for (i = 0; i < 4; i++) {
1050 		void __iomem *base = aaci->base + i * 0x14;
1051 
1052 		writel(0, base + AACI_IE);
1053 		writel(0, base + AACI_TXCR);
1054 		writel(0, base + AACI_RXCR);
1055 	}
1056 
1057 	writel(0x1fff, aaci->base + AACI_INTCLR);
1058 	writel(aaci->maincr, aaci->base + AACI_MAINCR);
1059 	/*
1060 	 * Fix: ac97 read back fail errors by reading
1061 	 * from any arbitrary aaci register.
1062 	 */
1063 	readl(aaci->base + AACI_CSCH1);
1064 	ret = aaci_probe_ac97(aaci);
1065 	if (ret)
1066 		goto out;
1067 
1068 	/*
1069 	 * Size the FIFOs (must be multiple of 16).
1070 	 */
1071 	aaci->fifosize = aaci_size_fifo(aaci);
1072 	if (aaci->fifosize & 15) {
1073 		printk(KERN_WARNING "AACI: fifosize = %d not supported\n",
1074 		       aaci->fifosize);
1075 		ret = -ENODEV;
1076 		goto out;
1077 	}
1078 
1079 	ret = aaci_init_pcm(aaci);
1080 	if (ret)
1081 		goto out;
1082 
1083 	snd_card_set_dev(aaci->card, &dev->dev);
1084 
1085 	ret = snd_card_register(aaci->card);
1086 	if (ret == 0) {
1087 		dev_info(&dev->dev, "%s, fifo %d\n", aaci->card->longname,
1088 			 aaci->fifosize);
1089 		amba_set_drvdata(dev, aaci->card);
1090 		return ret;
1091 	}
1092 
1093  out:
1094 	if (aaci)
1095 		snd_card_free(aaci->card);
1096 	amba_release_regions(dev);
1097 	return ret;
1098 }
1099 
1100 static int __devexit aaci_remove(struct amba_device *dev)
1101 {
1102 	struct snd_card *card = amba_get_drvdata(dev);
1103 
1104 	amba_set_drvdata(dev, NULL);
1105 
1106 	if (card) {
1107 		struct aaci *aaci = card->private_data;
1108 		writel(0, aaci->base + AACI_MAINCR);
1109 
1110 		snd_card_free(card);
1111 		amba_release_regions(dev);
1112 	}
1113 
1114 	return 0;
1115 }
1116 
1117 static struct amba_id aaci_ids[] = {
1118 	{
1119 		.id	= 0x00041041,
1120 		.mask	= 0x000fffff,
1121 	},
1122 	{ 0, 0 },
1123 };
1124 
1125 static struct amba_driver aaci_driver = {
1126 	.drv		= {
1127 		.name	= DRIVER_NAME,
1128 	},
1129 	.probe		= aaci_probe,
1130 	.remove		= __devexit_p(aaci_remove),
1131 	.suspend	= aaci_suspend,
1132 	.resume		= aaci_resume,
1133 	.id_table	= aaci_ids,
1134 };
1135 
1136 static int __init aaci_init(void)
1137 {
1138 	return amba_driver_register(&aaci_driver);
1139 }
1140 
1141 static void __exit aaci_exit(void)
1142 {
1143 	amba_driver_unregister(&aaci_driver);
1144 }
1145 
1146 module_init(aaci_init);
1147 module_exit(aaci_exit);
1148 
1149 MODULE_LICENSE("GPL");
1150 MODULE_DESCRIPTION("ARM PrimeCell PL041 Advanced Audio CODEC Interface driver");
1151