xref: /openbmc/linux/sound/atmel/ac97c.c (revision 4da722ca)
1 /*
2  * Driver for Atmel AC97C
3  *
4  * Copyright (C) 2005-2009 Atmel Corporation
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 as published by
8  * the Free Software Foundation.
9  */
10 #include <linux/clk.h>
11 #include <linux/delay.h>
12 #include <linux/bitmap.h>
13 #include <linux/device.h>
14 #include <linux/atmel_pdc.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/mutex.h>
20 #include <linux/gpio.h>
21 #include <linux/types.h>
22 #include <linux/io.h>
23 #include <linux/of.h>
24 #include <linux/of_gpio.h>
25 #include <linux/of_device.h>
26 
27 #include <sound/core.h>
28 #include <sound/initval.h>
29 #include <sound/pcm.h>
30 #include <sound/pcm_params.h>
31 #include <sound/ac97_codec.h>
32 #include <sound/atmel-ac97c.h>
33 #include <sound/memalloc.h>
34 
35 #include "ac97c.h"
36 
37 /* Serialize access to opened variable */
38 static DEFINE_MUTEX(opened_mutex);
39 
40 struct atmel_ac97c {
41 	struct clk			*pclk;
42 	struct platform_device		*pdev;
43 
44 	struct snd_pcm_substream	*playback_substream;
45 	struct snd_pcm_substream	*capture_substream;
46 	struct snd_card			*card;
47 	struct snd_pcm			*pcm;
48 	struct snd_ac97			*ac97;
49 	struct snd_ac97_bus		*ac97_bus;
50 
51 	u64				cur_format;
52 	unsigned int			cur_rate;
53 	int				playback_period, capture_period;
54 	/* Serialize access to opened variable */
55 	spinlock_t			lock;
56 	void __iomem			*regs;
57 	int				irq;
58 	int				opened;
59 	int				reset_pin;
60 };
61 
62 #define get_chip(card) ((struct atmel_ac97c *)(card)->private_data)
63 
64 #define ac97c_writel(chip, reg, val)			\
65 	__raw_writel((val), (chip)->regs + AC97C_##reg)
66 #define ac97c_readl(chip, reg)				\
67 	__raw_readl((chip)->regs + AC97C_##reg)
68 
69 static struct snd_pcm_hardware atmel_ac97c_hw = {
70 	.info			= (SNDRV_PCM_INFO_MMAP
71 				  | SNDRV_PCM_INFO_MMAP_VALID
72 				  | SNDRV_PCM_INFO_INTERLEAVED
73 				  | SNDRV_PCM_INFO_BLOCK_TRANSFER
74 				  | SNDRV_PCM_INFO_JOINT_DUPLEX
75 				  | SNDRV_PCM_INFO_RESUME
76 				  | SNDRV_PCM_INFO_PAUSE),
77 	.formats		= (SNDRV_PCM_FMTBIT_S16_BE
78 				  | SNDRV_PCM_FMTBIT_S16_LE),
79 	.rates			= (SNDRV_PCM_RATE_CONTINUOUS),
80 	.rate_min		= 4000,
81 	.rate_max		= 48000,
82 	.channels_min		= 1,
83 	.channels_max		= 2,
84 	.buffer_bytes_max	= 2 * 2 * 64 * 2048,
85 	.period_bytes_min	= 4096,
86 	.period_bytes_max	= 4096,
87 	.periods_min		= 6,
88 	.periods_max		= 64,
89 };
90 
91 static int atmel_ac97c_playback_open(struct snd_pcm_substream *substream)
92 {
93 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
94 	struct snd_pcm_runtime *runtime = substream->runtime;
95 
96 	mutex_lock(&opened_mutex);
97 	chip->opened++;
98 	runtime->hw = atmel_ac97c_hw;
99 	if (chip->cur_rate) {
100 		runtime->hw.rate_min = chip->cur_rate;
101 		runtime->hw.rate_max = chip->cur_rate;
102 	}
103 	if (chip->cur_format)
104 		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
105 	mutex_unlock(&opened_mutex);
106 	chip->playback_substream = substream;
107 	return 0;
108 }
109 
110 static int atmel_ac97c_capture_open(struct snd_pcm_substream *substream)
111 {
112 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
113 	struct snd_pcm_runtime *runtime = substream->runtime;
114 
115 	mutex_lock(&opened_mutex);
116 	chip->opened++;
117 	runtime->hw = atmel_ac97c_hw;
118 	if (chip->cur_rate) {
119 		runtime->hw.rate_min = chip->cur_rate;
120 		runtime->hw.rate_max = chip->cur_rate;
121 	}
122 	if (chip->cur_format)
123 		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
124 	mutex_unlock(&opened_mutex);
125 	chip->capture_substream = substream;
126 	return 0;
127 }
128 
129 static int atmel_ac97c_playback_close(struct snd_pcm_substream *substream)
130 {
131 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
132 
133 	mutex_lock(&opened_mutex);
134 	chip->opened--;
135 	if (!chip->opened) {
136 		chip->cur_rate = 0;
137 		chip->cur_format = 0;
138 	}
139 	mutex_unlock(&opened_mutex);
140 
141 	chip->playback_substream = NULL;
142 
143 	return 0;
144 }
145 
146 static int atmel_ac97c_capture_close(struct snd_pcm_substream *substream)
147 {
148 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
149 
150 	mutex_lock(&opened_mutex);
151 	chip->opened--;
152 	if (!chip->opened) {
153 		chip->cur_rate = 0;
154 		chip->cur_format = 0;
155 	}
156 	mutex_unlock(&opened_mutex);
157 
158 	chip->capture_substream = NULL;
159 
160 	return 0;
161 }
162 
163 static int atmel_ac97c_playback_hw_params(struct snd_pcm_substream *substream,
164 		struct snd_pcm_hw_params *hw_params)
165 {
166 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
167 	int retval;
168 
169 	retval = snd_pcm_lib_malloc_pages(substream,
170 					params_buffer_bytes(hw_params));
171 	if (retval < 0)
172 		return retval;
173 
174 	/* Set restrictions to params. */
175 	mutex_lock(&opened_mutex);
176 	chip->cur_rate = params_rate(hw_params);
177 	chip->cur_format = params_format(hw_params);
178 	mutex_unlock(&opened_mutex);
179 
180 	return retval;
181 }
182 
183 static int atmel_ac97c_capture_hw_params(struct snd_pcm_substream *substream,
184 		struct snd_pcm_hw_params *hw_params)
185 {
186 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
187 	int retval;
188 
189 	retval = snd_pcm_lib_malloc_pages(substream,
190 					params_buffer_bytes(hw_params));
191 	if (retval < 0)
192 		return retval;
193 
194 	/* Set restrictions to params. */
195 	mutex_lock(&opened_mutex);
196 	chip->cur_rate = params_rate(hw_params);
197 	chip->cur_format = params_format(hw_params);
198 	mutex_unlock(&opened_mutex);
199 
200 	return retval;
201 }
202 
203 static int atmel_ac97c_playback_prepare(struct snd_pcm_substream *substream)
204 {
205 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
206 	struct snd_pcm_runtime *runtime = substream->runtime;
207 	int block_size = frames_to_bytes(runtime, runtime->period_size);
208 	unsigned long word = ac97c_readl(chip, OCA);
209 	int retval;
210 
211 	chip->playback_period = 0;
212 	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
213 
214 	/* assign channels to AC97C channel A */
215 	switch (runtime->channels) {
216 	case 1:
217 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
218 		break;
219 	case 2:
220 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
221 			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
222 		break;
223 	default:
224 		/* TODO: support more than two channels */
225 		return -EINVAL;
226 	}
227 	ac97c_writel(chip, OCA, word);
228 
229 	/* configure sample format and size */
230 	word = ac97c_readl(chip, CAMR);
231 	if (chip->opened <= 1)
232 		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
233 	else
234 		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
235 
236 	switch (runtime->format) {
237 	case SNDRV_PCM_FORMAT_S16_LE:
238 		break;
239 	case SNDRV_PCM_FORMAT_S16_BE: /* fall through */
240 		word &= ~(AC97C_CMR_CEM_LITTLE);
241 		break;
242 	default:
243 		word = ac97c_readl(chip, OCA);
244 		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
245 		ac97c_writel(chip, OCA, word);
246 		return -EINVAL;
247 	}
248 
249 	/* Enable underrun interrupt on channel A */
250 	word |= AC97C_CSR_UNRUN;
251 
252 	ac97c_writel(chip, CAMR, word);
253 
254 	/* Enable channel A event interrupt */
255 	word = ac97c_readl(chip, IMR);
256 	word |= AC97C_SR_CAEVT;
257 	ac97c_writel(chip, IER, word);
258 
259 	/* set variable rate if needed */
260 	if (runtime->rate != 48000) {
261 		word = ac97c_readl(chip, MR);
262 		word |= AC97C_MR_VRA;
263 		ac97c_writel(chip, MR, word);
264 	} else {
265 		word = ac97c_readl(chip, MR);
266 		word &= ~(AC97C_MR_VRA);
267 		ac97c_writel(chip, MR, word);
268 	}
269 
270 	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_FRONT_DAC_RATE,
271 			runtime->rate);
272 	if (retval)
273 		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
274 				runtime->rate);
275 
276 	/* Initialize and start the PDC */
277 	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_TPR);
278 	writel(block_size / 2, chip->regs + ATMEL_PDC_TCR);
279 	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_TNPR);
280 	writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
281 
282 	return retval;
283 }
284 
285 static int atmel_ac97c_capture_prepare(struct snd_pcm_substream *substream)
286 {
287 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
288 	struct snd_pcm_runtime *runtime = substream->runtime;
289 	int block_size = frames_to_bytes(runtime, runtime->period_size);
290 	unsigned long word = ac97c_readl(chip, ICA);
291 	int retval;
292 
293 	chip->capture_period = 0;
294 	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
295 
296 	/* assign channels to AC97C channel A */
297 	switch (runtime->channels) {
298 	case 1:
299 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
300 		break;
301 	case 2:
302 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
303 			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
304 		break;
305 	default:
306 		/* TODO: support more than two channels */
307 		return -EINVAL;
308 	}
309 	ac97c_writel(chip, ICA, word);
310 
311 	/* configure sample format and size */
312 	word = ac97c_readl(chip, CAMR);
313 	if (chip->opened <= 1)
314 		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
315 	else
316 		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
317 
318 	switch (runtime->format) {
319 	case SNDRV_PCM_FORMAT_S16_LE:
320 		break;
321 	case SNDRV_PCM_FORMAT_S16_BE: /* fall through */
322 		word &= ~(AC97C_CMR_CEM_LITTLE);
323 		break;
324 	default:
325 		word = ac97c_readl(chip, ICA);
326 		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
327 		ac97c_writel(chip, ICA, word);
328 		return -EINVAL;
329 	}
330 
331 	/* Enable overrun interrupt on channel A */
332 	word |= AC97C_CSR_OVRUN;
333 
334 	ac97c_writel(chip, CAMR, word);
335 
336 	/* Enable channel A event interrupt */
337 	word = ac97c_readl(chip, IMR);
338 	word |= AC97C_SR_CAEVT;
339 	ac97c_writel(chip, IER, word);
340 
341 	/* set variable rate if needed */
342 	if (runtime->rate != 48000) {
343 		word = ac97c_readl(chip, MR);
344 		word |= AC97C_MR_VRA;
345 		ac97c_writel(chip, MR, word);
346 	} else {
347 		word = ac97c_readl(chip, MR);
348 		word &= ~(AC97C_MR_VRA);
349 		ac97c_writel(chip, MR, word);
350 	}
351 
352 	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_LR_ADC_RATE,
353 			runtime->rate);
354 	if (retval)
355 		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
356 				runtime->rate);
357 
358 	/* Initialize and start the PDC */
359 	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_RPR);
360 	writel(block_size / 2, chip->regs + ATMEL_PDC_RCR);
361 	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_RNPR);
362 	writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
363 
364 	return retval;
365 }
366 
367 static int
368 atmel_ac97c_playback_trigger(struct snd_pcm_substream *substream, int cmd)
369 {
370 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
371 	unsigned long camr, ptcr = 0;
372 
373 	camr = ac97c_readl(chip, CAMR);
374 
375 	switch (cmd) {
376 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: /* fall through */
377 	case SNDRV_PCM_TRIGGER_RESUME: /* fall through */
378 	case SNDRV_PCM_TRIGGER_START:
379 		ptcr = ATMEL_PDC_TXTEN;
380 		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDTX;
381 		break;
382 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH: /* fall through */
383 	case SNDRV_PCM_TRIGGER_SUSPEND: /* fall through */
384 	case SNDRV_PCM_TRIGGER_STOP:
385 		ptcr |= ATMEL_PDC_TXTDIS;
386 		if (chip->opened <= 1)
387 			camr &= ~AC97C_CMR_CENA;
388 		break;
389 	default:
390 		return -EINVAL;
391 	}
392 
393 	ac97c_writel(chip, CAMR, camr);
394 	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
395 	return 0;
396 }
397 
398 static int
399 atmel_ac97c_capture_trigger(struct snd_pcm_substream *substream, int cmd)
400 {
401 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
402 	unsigned long camr, ptcr = 0;
403 
404 	camr = ac97c_readl(chip, CAMR);
405 	ptcr = readl(chip->regs + ATMEL_PDC_PTSR);
406 
407 	switch (cmd) {
408 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: /* fall through */
409 	case SNDRV_PCM_TRIGGER_RESUME: /* fall through */
410 	case SNDRV_PCM_TRIGGER_START:
411 		ptcr = ATMEL_PDC_RXTEN;
412 		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDRX;
413 		break;
414 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH: /* fall through */
415 	case SNDRV_PCM_TRIGGER_SUSPEND: /* fall through */
416 	case SNDRV_PCM_TRIGGER_STOP:
417 		ptcr |= ATMEL_PDC_RXTDIS;
418 		if (chip->opened <= 1)
419 			camr &= ~AC97C_CMR_CENA;
420 		break;
421 	default:
422 		return -EINVAL;
423 	}
424 
425 	ac97c_writel(chip, CAMR, camr);
426 	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
427 	return 0;
428 }
429 
430 static snd_pcm_uframes_t
431 atmel_ac97c_playback_pointer(struct snd_pcm_substream *substream)
432 {
433 	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
434 	struct snd_pcm_runtime	*runtime = substream->runtime;
435 	snd_pcm_uframes_t	frames;
436 	unsigned long		bytes;
437 
438 	bytes = readl(chip->regs + ATMEL_PDC_TPR);
439 	bytes -= runtime->dma_addr;
440 
441 	frames = bytes_to_frames(runtime, bytes);
442 	if (frames >= runtime->buffer_size)
443 		frames -= runtime->buffer_size;
444 	return frames;
445 }
446 
447 static snd_pcm_uframes_t
448 atmel_ac97c_capture_pointer(struct snd_pcm_substream *substream)
449 {
450 	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
451 	struct snd_pcm_runtime	*runtime = substream->runtime;
452 	snd_pcm_uframes_t	frames;
453 	unsigned long		bytes;
454 
455 	bytes = readl(chip->regs + ATMEL_PDC_RPR);
456 	bytes -= runtime->dma_addr;
457 
458 	frames = bytes_to_frames(runtime, bytes);
459 	if (frames >= runtime->buffer_size)
460 		frames -= runtime->buffer_size;
461 	return frames;
462 }
463 
464 static struct snd_pcm_ops atmel_ac97_playback_ops = {
465 	.open		= atmel_ac97c_playback_open,
466 	.close		= atmel_ac97c_playback_close,
467 	.ioctl		= snd_pcm_lib_ioctl,
468 	.hw_params	= atmel_ac97c_playback_hw_params,
469 	.hw_free	= snd_pcm_lib_free_pages,
470 	.prepare	= atmel_ac97c_playback_prepare,
471 	.trigger	= atmel_ac97c_playback_trigger,
472 	.pointer	= atmel_ac97c_playback_pointer,
473 };
474 
475 static struct snd_pcm_ops atmel_ac97_capture_ops = {
476 	.open		= atmel_ac97c_capture_open,
477 	.close		= atmel_ac97c_capture_close,
478 	.ioctl		= snd_pcm_lib_ioctl,
479 	.hw_params	= atmel_ac97c_capture_hw_params,
480 	.hw_free	= snd_pcm_lib_free_pages,
481 	.prepare	= atmel_ac97c_capture_prepare,
482 	.trigger	= atmel_ac97c_capture_trigger,
483 	.pointer	= atmel_ac97c_capture_pointer,
484 };
485 
486 static irqreturn_t atmel_ac97c_interrupt(int irq, void *dev)
487 {
488 	struct atmel_ac97c	*chip  = (struct atmel_ac97c *)dev;
489 	irqreturn_t		retval = IRQ_NONE;
490 	u32			sr     = ac97c_readl(chip, SR);
491 	u32			casr   = ac97c_readl(chip, CASR);
492 	u32			cosr   = ac97c_readl(chip, COSR);
493 	u32			camr   = ac97c_readl(chip, CAMR);
494 
495 	if (sr & AC97C_SR_CAEVT) {
496 		struct snd_pcm_runtime *runtime;
497 		int offset, next_period, block_size;
498 		dev_dbg(&chip->pdev->dev, "channel A event%s%s%s%s%s%s\n",
499 				casr & AC97C_CSR_OVRUN   ? " OVRUN"   : "",
500 				casr & AC97C_CSR_RXRDY   ? " RXRDY"   : "",
501 				casr & AC97C_CSR_UNRUN   ? " UNRUN"   : "",
502 				casr & AC97C_CSR_TXEMPTY ? " TXEMPTY" : "",
503 				casr & AC97C_CSR_TXRDY   ? " TXRDY"   : "",
504 				!casr                    ? " NONE"    : "");
505 		if ((casr & camr) & AC97C_CSR_ENDTX) {
506 			runtime = chip->playback_substream->runtime;
507 			block_size = frames_to_bytes(runtime, runtime->period_size);
508 			chip->playback_period++;
509 
510 			if (chip->playback_period == runtime->periods)
511 				chip->playback_period = 0;
512 			next_period = chip->playback_period + 1;
513 			if (next_period == runtime->periods)
514 				next_period = 0;
515 
516 			offset = block_size * next_period;
517 
518 			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_TNPR);
519 			writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
520 
521 			snd_pcm_period_elapsed(chip->playback_substream);
522 		}
523 		if ((casr & camr) & AC97C_CSR_ENDRX) {
524 			runtime = chip->capture_substream->runtime;
525 			block_size = frames_to_bytes(runtime, runtime->period_size);
526 			chip->capture_period++;
527 
528 			if (chip->capture_period == runtime->periods)
529 				chip->capture_period = 0;
530 			next_period = chip->capture_period + 1;
531 			if (next_period == runtime->periods)
532 				next_period = 0;
533 
534 			offset = block_size * next_period;
535 
536 			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_RNPR);
537 			writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
538 			snd_pcm_period_elapsed(chip->capture_substream);
539 		}
540 		retval = IRQ_HANDLED;
541 	}
542 
543 	if (sr & AC97C_SR_COEVT) {
544 		dev_info(&chip->pdev->dev, "codec channel event%s%s%s%s%s\n",
545 				cosr & AC97C_CSR_OVRUN   ? " OVRUN"   : "",
546 				cosr & AC97C_CSR_RXRDY   ? " RXRDY"   : "",
547 				cosr & AC97C_CSR_TXEMPTY ? " TXEMPTY" : "",
548 				cosr & AC97C_CSR_TXRDY   ? " TXRDY"   : "",
549 				!cosr                    ? " NONE"    : "");
550 		retval = IRQ_HANDLED;
551 	}
552 
553 	if (retval == IRQ_NONE) {
554 		dev_err(&chip->pdev->dev, "spurious interrupt sr 0x%08x "
555 				"casr 0x%08x cosr 0x%08x\n", sr, casr, cosr);
556 	}
557 
558 	return retval;
559 }
560 
561 static struct ac97_pcm at91_ac97_pcm_defs[] = {
562 	/* Playback */
563 	{
564 		.exclusive = 1,
565 		.r = { {
566 			.slots = ((1 << AC97_SLOT_PCM_LEFT)
567 				  | (1 << AC97_SLOT_PCM_RIGHT)),
568 		} },
569 	},
570 	/* PCM in */
571 	{
572 		.stream = 1,
573 		.exclusive = 1,
574 		.r = { {
575 			.slots = ((1 << AC97_SLOT_PCM_LEFT)
576 					| (1 << AC97_SLOT_PCM_RIGHT)),
577 		} }
578 	},
579 	/* Mic in */
580 	{
581 		.stream = 1,
582 		.exclusive = 1,
583 		.r = { {
584 			.slots = (1<<AC97_SLOT_MIC),
585 		} }
586 	},
587 };
588 
589 static int atmel_ac97c_pcm_new(struct atmel_ac97c *chip)
590 {
591 	struct snd_pcm		*pcm;
592 	struct snd_pcm_hardware	hw = atmel_ac97c_hw;
593 	int			retval;
594 
595 	retval = snd_ac97_pcm_assign(chip->ac97_bus,
596 				     ARRAY_SIZE(at91_ac97_pcm_defs),
597 				     at91_ac97_pcm_defs);
598 	if (retval)
599 		return retval;
600 
601 	retval = snd_pcm_new(chip->card, chip->card->shortname, 0, 1, 1, &pcm);
602 	if (retval)
603 		return retval;
604 
605 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &atmel_ac97_capture_ops);
606 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &atmel_ac97_playback_ops);
607 
608 	retval = snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
609 			&chip->pdev->dev, hw.periods_min * hw.period_bytes_min,
610 			hw.buffer_bytes_max);
611 	if (retval)
612 		return retval;
613 
614 	pcm->private_data = chip;
615 	pcm->info_flags = 0;
616 	strcpy(pcm->name, chip->card->shortname);
617 	chip->pcm = pcm;
618 
619 	return 0;
620 }
621 
622 static int atmel_ac97c_mixer_new(struct atmel_ac97c *chip)
623 {
624 	struct snd_ac97_template template;
625 	memset(&template, 0, sizeof(template));
626 	template.private_data = chip;
627 	return snd_ac97_mixer(chip->ac97_bus, &template, &chip->ac97);
628 }
629 
630 static void atmel_ac97c_write(struct snd_ac97 *ac97, unsigned short reg,
631 		unsigned short val)
632 {
633 	struct atmel_ac97c *chip = get_chip(ac97);
634 	unsigned long word;
635 	int timeout = 40;
636 
637 	word = (reg & 0x7f) << 16 | val;
638 
639 	do {
640 		if (ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) {
641 			ac97c_writel(chip, COTHR, word);
642 			return;
643 		}
644 		udelay(1);
645 	} while (--timeout);
646 
647 	dev_dbg(&chip->pdev->dev, "codec write timeout\n");
648 }
649 
650 static unsigned short atmel_ac97c_read(struct snd_ac97 *ac97,
651 		unsigned short reg)
652 {
653 	struct atmel_ac97c *chip = get_chip(ac97);
654 	unsigned long word;
655 	int timeout = 40;
656 	int write = 10;
657 
658 	word = (0x80 | (reg & 0x7f)) << 16;
659 
660 	if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0)
661 		ac97c_readl(chip, CORHR);
662 
663 retry_write:
664 	timeout = 40;
665 
666 	do {
667 		if ((ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) != 0) {
668 			ac97c_writel(chip, COTHR, word);
669 			goto read_reg;
670 		}
671 		udelay(10);
672 	} while (--timeout);
673 
674 	if (!--write)
675 		goto timed_out;
676 	goto retry_write;
677 
678 read_reg:
679 	do {
680 		if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0) {
681 			unsigned short val = ac97c_readl(chip, CORHR);
682 			return val;
683 		}
684 		udelay(10);
685 	} while (--timeout);
686 
687 	if (!--write)
688 		goto timed_out;
689 	goto retry_write;
690 
691 timed_out:
692 	dev_dbg(&chip->pdev->dev, "codec read timeout\n");
693 	return 0xffff;
694 }
695 
696 static void atmel_ac97c_reset(struct atmel_ac97c *chip)
697 {
698 	ac97c_writel(chip, MR,   0);
699 	ac97c_writel(chip, MR,   AC97C_MR_ENA);
700 	ac97c_writel(chip, CAMR, 0);
701 	ac97c_writel(chip, COMR, 0);
702 
703 	if (gpio_is_valid(chip->reset_pin)) {
704 		gpio_set_value(chip->reset_pin, 0);
705 		/* AC97 v2.2 specifications says minimum 1 us. */
706 		udelay(2);
707 		gpio_set_value(chip->reset_pin, 1);
708 	} else {
709 		ac97c_writel(chip, MR, AC97C_MR_WRST | AC97C_MR_ENA);
710 		udelay(2);
711 		ac97c_writel(chip, MR, AC97C_MR_ENA);
712 	}
713 }
714 
715 #ifdef CONFIG_OF
716 static const struct of_device_id atmel_ac97c_dt_ids[] = {
717 	{ .compatible = "atmel,at91sam9263-ac97c", },
718 	{ }
719 };
720 MODULE_DEVICE_TABLE(of, atmel_ac97c_dt_ids);
721 
722 static struct ac97c_platform_data *atmel_ac97c_probe_dt(struct device *dev)
723 {
724 	struct ac97c_platform_data *pdata;
725 	struct device_node *node = dev->of_node;
726 
727 	if (!node) {
728 		dev_err(dev, "Device does not have associated DT data\n");
729 		return ERR_PTR(-EINVAL);
730 	}
731 
732 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
733 	if (!pdata)
734 		return ERR_PTR(-ENOMEM);
735 
736 	pdata->reset_pin = of_get_named_gpio(dev->of_node, "ac97-gpios", 2);
737 
738 	return pdata;
739 }
740 #else
741 static struct ac97c_platform_data *atmel_ac97c_probe_dt(struct device *dev)
742 {
743 	dev_err(dev, "no platform data defined\n");
744 	return ERR_PTR(-ENXIO);
745 }
746 #endif
747 
748 static int atmel_ac97c_probe(struct platform_device *pdev)
749 {
750 	struct snd_card			*card;
751 	struct atmel_ac97c		*chip;
752 	struct resource			*regs;
753 	struct ac97c_platform_data	*pdata;
754 	struct clk			*pclk;
755 	static struct snd_ac97_bus_ops	ops = {
756 		.write	= atmel_ac97c_write,
757 		.read	= atmel_ac97c_read,
758 	};
759 	int				retval;
760 	int				irq;
761 
762 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
763 	if (!regs) {
764 		dev_dbg(&pdev->dev, "no memory resource\n");
765 		return -ENXIO;
766 	}
767 
768 	pdata = dev_get_platdata(&pdev->dev);
769 	if (!pdata) {
770 		pdata = atmel_ac97c_probe_dt(&pdev->dev);
771 		if (IS_ERR(pdata))
772 			return PTR_ERR(pdata);
773 	}
774 
775 	irq = platform_get_irq(pdev, 0);
776 	if (irq < 0) {
777 		dev_dbg(&pdev->dev, "could not get irq: %d\n", irq);
778 		return irq;
779 	}
780 
781 	pclk = clk_get(&pdev->dev, "ac97_clk");
782 	if (IS_ERR(pclk)) {
783 		dev_dbg(&pdev->dev, "no peripheral clock\n");
784 		return PTR_ERR(pclk);
785 	}
786 	clk_prepare_enable(pclk);
787 
788 	retval = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1,
789 			      SNDRV_DEFAULT_STR1, THIS_MODULE,
790 			      sizeof(struct atmel_ac97c), &card);
791 	if (retval) {
792 		dev_dbg(&pdev->dev, "could not create sound card device\n");
793 		goto err_snd_card_new;
794 	}
795 
796 	chip = get_chip(card);
797 
798 	retval = request_irq(irq, atmel_ac97c_interrupt, 0, "AC97C", chip);
799 	if (retval) {
800 		dev_dbg(&pdev->dev, "unable to request irq %d\n", irq);
801 		goto err_request_irq;
802 	}
803 	chip->irq = irq;
804 
805 	spin_lock_init(&chip->lock);
806 
807 	strcpy(card->driver, "Atmel AC97C");
808 	strcpy(card->shortname, "Atmel AC97C");
809 	sprintf(card->longname, "Atmel AC97 controller");
810 
811 	chip->card = card;
812 	chip->pclk = pclk;
813 	chip->pdev = pdev;
814 	chip->regs = ioremap(regs->start, resource_size(regs));
815 
816 	if (!chip->regs) {
817 		dev_dbg(&pdev->dev, "could not remap register memory\n");
818 		retval = -ENOMEM;
819 		goto err_ioremap;
820 	}
821 
822 	if (gpio_is_valid(pdata->reset_pin)) {
823 		if (gpio_request(pdata->reset_pin, "reset_pin")) {
824 			dev_dbg(&pdev->dev, "reset pin not available\n");
825 			chip->reset_pin = -ENODEV;
826 		} else {
827 			gpio_direction_output(pdata->reset_pin, 1);
828 			chip->reset_pin = pdata->reset_pin;
829 		}
830 	} else {
831 		chip->reset_pin = -EINVAL;
832 	}
833 
834 	atmel_ac97c_reset(chip);
835 
836 	/* Enable overrun interrupt from codec channel */
837 	ac97c_writel(chip, COMR, AC97C_CSR_OVRUN);
838 	ac97c_writel(chip, IER, ac97c_readl(chip, IMR) | AC97C_SR_COEVT);
839 
840 	retval = snd_ac97_bus(card, 0, &ops, chip, &chip->ac97_bus);
841 	if (retval) {
842 		dev_dbg(&pdev->dev, "could not register on ac97 bus\n");
843 		goto err_ac97_bus;
844 	}
845 
846 	retval = atmel_ac97c_mixer_new(chip);
847 	if (retval) {
848 		dev_dbg(&pdev->dev, "could not register ac97 mixer\n");
849 		goto err_ac97_bus;
850 	}
851 
852 	retval = atmel_ac97c_pcm_new(chip);
853 	if (retval) {
854 		dev_dbg(&pdev->dev, "could not register ac97 pcm device\n");
855 		goto err_ac97_bus;
856 	}
857 
858 	retval = snd_card_register(card);
859 	if (retval) {
860 		dev_dbg(&pdev->dev, "could not register sound card\n");
861 		goto err_ac97_bus;
862 	}
863 
864 	platform_set_drvdata(pdev, card);
865 
866 	dev_info(&pdev->dev, "Atmel AC97 controller at 0x%p, irq = %d\n",
867 			chip->regs, irq);
868 
869 	return 0;
870 
871 err_ac97_bus:
872 	if (gpio_is_valid(chip->reset_pin))
873 		gpio_free(chip->reset_pin);
874 
875 	iounmap(chip->regs);
876 err_ioremap:
877 	free_irq(irq, chip);
878 err_request_irq:
879 	snd_card_free(card);
880 err_snd_card_new:
881 	clk_disable_unprepare(pclk);
882 	clk_put(pclk);
883 	return retval;
884 }
885 
886 #ifdef CONFIG_PM_SLEEP
887 static int atmel_ac97c_suspend(struct device *pdev)
888 {
889 	struct snd_card *card = dev_get_drvdata(pdev);
890 	struct atmel_ac97c *chip = card->private_data;
891 
892 	clk_disable_unprepare(chip->pclk);
893 	return 0;
894 }
895 
896 static int atmel_ac97c_resume(struct device *pdev)
897 {
898 	struct snd_card *card = dev_get_drvdata(pdev);
899 	struct atmel_ac97c *chip = card->private_data;
900 
901 	clk_prepare_enable(chip->pclk);
902 	return 0;
903 }
904 
905 static SIMPLE_DEV_PM_OPS(atmel_ac97c_pm, atmel_ac97c_suspend, atmel_ac97c_resume);
906 #define ATMEL_AC97C_PM_OPS	&atmel_ac97c_pm
907 #else
908 #define ATMEL_AC97C_PM_OPS	NULL
909 #endif
910 
911 static int atmel_ac97c_remove(struct platform_device *pdev)
912 {
913 	struct snd_card *card = platform_get_drvdata(pdev);
914 	struct atmel_ac97c *chip = get_chip(card);
915 
916 	if (gpio_is_valid(chip->reset_pin))
917 		gpio_free(chip->reset_pin);
918 
919 	ac97c_writel(chip, CAMR, 0);
920 	ac97c_writel(chip, COMR, 0);
921 	ac97c_writel(chip, MR,   0);
922 
923 	clk_disable_unprepare(chip->pclk);
924 	clk_put(chip->pclk);
925 	iounmap(chip->regs);
926 	free_irq(chip->irq, chip);
927 
928 	snd_card_free(card);
929 
930 	return 0;
931 }
932 
933 static struct platform_driver atmel_ac97c_driver = {
934 	.probe		= atmel_ac97c_probe,
935 	.remove		= atmel_ac97c_remove,
936 	.driver		= {
937 		.name	= "atmel_ac97c",
938 		.pm	= ATMEL_AC97C_PM_OPS,
939 		.of_match_table = of_match_ptr(atmel_ac97c_dt_ids),
940 	},
941 };
942 module_platform_driver(atmel_ac97c_driver);
943 
944 MODULE_LICENSE("GPL");
945 MODULE_DESCRIPTION("Driver for Atmel AC97 controller");
946 MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
947