xref: /linux/sound/atmel/ac97c.c (revision 3213486f2e442831e324cc6201a2f9e924ecc235)
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/gpio/consumer.h>
16 #include <linux/init.h>
17 #include <linux/interrupt.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/mutex.h>
21 #include <linux/types.h>
22 #include <linux/io.h>
23 #include <linux/of.h>
24 #include <linux/of_device.h>
25 
26 #include <sound/core.h>
27 #include <sound/initval.h>
28 #include <sound/pcm.h>
29 #include <sound/pcm_params.h>
30 #include <sound/ac97_codec.h>
31 #include <sound/memalloc.h>
32 
33 #include "ac97c.h"
34 
35 /* Serialize access to opened variable */
36 static DEFINE_MUTEX(opened_mutex);
37 
38 struct atmel_ac97c {
39 	struct clk			*pclk;
40 	struct platform_device		*pdev;
41 
42 	struct snd_pcm_substream	*playback_substream;
43 	struct snd_pcm_substream	*capture_substream;
44 	struct snd_card			*card;
45 	struct snd_pcm			*pcm;
46 	struct snd_ac97			*ac97;
47 	struct snd_ac97_bus		*ac97_bus;
48 
49 	u64				cur_format;
50 	unsigned int			cur_rate;
51 	int				playback_period, capture_period;
52 	/* Serialize access to opened variable */
53 	spinlock_t			lock;
54 	void __iomem			*regs;
55 	int				irq;
56 	int				opened;
57 	struct gpio_desc		*reset_pin;
58 };
59 
60 #define get_chip(card) ((struct atmel_ac97c *)(card)->private_data)
61 
62 #define ac97c_writel(chip, reg, val)			\
63 	__raw_writel((val), (chip)->regs + AC97C_##reg)
64 #define ac97c_readl(chip, reg)				\
65 	__raw_readl((chip)->regs + AC97C_##reg)
66 
67 static const struct snd_pcm_hardware atmel_ac97c_hw = {
68 	.info			= (SNDRV_PCM_INFO_MMAP
69 				  | SNDRV_PCM_INFO_MMAP_VALID
70 				  | SNDRV_PCM_INFO_INTERLEAVED
71 				  | SNDRV_PCM_INFO_BLOCK_TRANSFER
72 				  | SNDRV_PCM_INFO_JOINT_DUPLEX
73 				  | SNDRV_PCM_INFO_RESUME
74 				  | SNDRV_PCM_INFO_PAUSE),
75 	.formats		= (SNDRV_PCM_FMTBIT_S16_BE
76 				  | SNDRV_PCM_FMTBIT_S16_LE),
77 	.rates			= (SNDRV_PCM_RATE_CONTINUOUS),
78 	.rate_min		= 4000,
79 	.rate_max		= 48000,
80 	.channels_min		= 1,
81 	.channels_max		= 2,
82 	.buffer_bytes_max	= 2 * 2 * 64 * 2048,
83 	.period_bytes_min	= 4096,
84 	.period_bytes_max	= 4096,
85 	.periods_min		= 6,
86 	.periods_max		= 64,
87 };
88 
89 static int atmel_ac97c_playback_open(struct snd_pcm_substream *substream)
90 {
91 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
92 	struct snd_pcm_runtime *runtime = substream->runtime;
93 
94 	mutex_lock(&opened_mutex);
95 	chip->opened++;
96 	runtime->hw = atmel_ac97c_hw;
97 	if (chip->cur_rate) {
98 		runtime->hw.rate_min = chip->cur_rate;
99 		runtime->hw.rate_max = chip->cur_rate;
100 	}
101 	if (chip->cur_format)
102 		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
103 	mutex_unlock(&opened_mutex);
104 	chip->playback_substream = substream;
105 	return 0;
106 }
107 
108 static int atmel_ac97c_capture_open(struct snd_pcm_substream *substream)
109 {
110 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
111 	struct snd_pcm_runtime *runtime = substream->runtime;
112 
113 	mutex_lock(&opened_mutex);
114 	chip->opened++;
115 	runtime->hw = atmel_ac97c_hw;
116 	if (chip->cur_rate) {
117 		runtime->hw.rate_min = chip->cur_rate;
118 		runtime->hw.rate_max = chip->cur_rate;
119 	}
120 	if (chip->cur_format)
121 		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
122 	mutex_unlock(&opened_mutex);
123 	chip->capture_substream = substream;
124 	return 0;
125 }
126 
127 static int atmel_ac97c_playback_close(struct snd_pcm_substream *substream)
128 {
129 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
130 
131 	mutex_lock(&opened_mutex);
132 	chip->opened--;
133 	if (!chip->opened) {
134 		chip->cur_rate = 0;
135 		chip->cur_format = 0;
136 	}
137 	mutex_unlock(&opened_mutex);
138 
139 	chip->playback_substream = NULL;
140 
141 	return 0;
142 }
143 
144 static int atmel_ac97c_capture_close(struct snd_pcm_substream *substream)
145 {
146 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
147 
148 	mutex_lock(&opened_mutex);
149 	chip->opened--;
150 	if (!chip->opened) {
151 		chip->cur_rate = 0;
152 		chip->cur_format = 0;
153 	}
154 	mutex_unlock(&opened_mutex);
155 
156 	chip->capture_substream = NULL;
157 
158 	return 0;
159 }
160 
161 static int atmel_ac97c_playback_hw_params(struct snd_pcm_substream *substream,
162 		struct snd_pcm_hw_params *hw_params)
163 {
164 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
165 	int retval;
166 
167 	retval = snd_pcm_lib_malloc_pages(substream,
168 					params_buffer_bytes(hw_params));
169 	if (retval < 0)
170 		return retval;
171 
172 	/* Set restrictions to params. */
173 	mutex_lock(&opened_mutex);
174 	chip->cur_rate = params_rate(hw_params);
175 	chip->cur_format = params_format(hw_params);
176 	mutex_unlock(&opened_mutex);
177 
178 	return retval;
179 }
180 
181 static int atmel_ac97c_capture_hw_params(struct snd_pcm_substream *substream,
182 		struct snd_pcm_hw_params *hw_params)
183 {
184 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
185 	int retval;
186 
187 	retval = snd_pcm_lib_malloc_pages(substream,
188 					params_buffer_bytes(hw_params));
189 	if (retval < 0)
190 		return retval;
191 
192 	/* Set restrictions to params. */
193 	mutex_lock(&opened_mutex);
194 	chip->cur_rate = params_rate(hw_params);
195 	chip->cur_format = params_format(hw_params);
196 	mutex_unlock(&opened_mutex);
197 
198 	return retval;
199 }
200 
201 static int atmel_ac97c_playback_prepare(struct snd_pcm_substream *substream)
202 {
203 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
204 	struct snd_pcm_runtime *runtime = substream->runtime;
205 	int block_size = frames_to_bytes(runtime, runtime->period_size);
206 	unsigned long word = ac97c_readl(chip, OCA);
207 	int retval;
208 
209 	chip->playback_period = 0;
210 	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
211 
212 	/* assign channels to AC97C channel A */
213 	switch (runtime->channels) {
214 	case 1:
215 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
216 		break;
217 	case 2:
218 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
219 			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
220 		break;
221 	default:
222 		/* TODO: support more than two channels */
223 		return -EINVAL;
224 	}
225 	ac97c_writel(chip, OCA, word);
226 
227 	/* configure sample format and size */
228 	word = ac97c_readl(chip, CAMR);
229 	if (chip->opened <= 1)
230 		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
231 	else
232 		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
233 
234 	switch (runtime->format) {
235 	case SNDRV_PCM_FORMAT_S16_LE:
236 		break;
237 	case SNDRV_PCM_FORMAT_S16_BE: /* fall through */
238 		word &= ~(AC97C_CMR_CEM_LITTLE);
239 		break;
240 	default:
241 		word = ac97c_readl(chip, OCA);
242 		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
243 		ac97c_writel(chip, OCA, word);
244 		return -EINVAL;
245 	}
246 
247 	/* Enable underrun interrupt on channel A */
248 	word |= AC97C_CSR_UNRUN;
249 
250 	ac97c_writel(chip, CAMR, word);
251 
252 	/* Enable channel A event interrupt */
253 	word = ac97c_readl(chip, IMR);
254 	word |= AC97C_SR_CAEVT;
255 	ac97c_writel(chip, IER, word);
256 
257 	/* set variable rate if needed */
258 	if (runtime->rate != 48000) {
259 		word = ac97c_readl(chip, MR);
260 		word |= AC97C_MR_VRA;
261 		ac97c_writel(chip, MR, word);
262 	} else {
263 		word = ac97c_readl(chip, MR);
264 		word &= ~(AC97C_MR_VRA);
265 		ac97c_writel(chip, MR, word);
266 	}
267 
268 	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_FRONT_DAC_RATE,
269 			runtime->rate);
270 	if (retval)
271 		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
272 				runtime->rate);
273 
274 	/* Initialize and start the PDC */
275 	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_TPR);
276 	writel(block_size / 2, chip->regs + ATMEL_PDC_TCR);
277 	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_TNPR);
278 	writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
279 
280 	return retval;
281 }
282 
283 static int atmel_ac97c_capture_prepare(struct snd_pcm_substream *substream)
284 {
285 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
286 	struct snd_pcm_runtime *runtime = substream->runtime;
287 	int block_size = frames_to_bytes(runtime, runtime->period_size);
288 	unsigned long word = ac97c_readl(chip, ICA);
289 	int retval;
290 
291 	chip->capture_period = 0;
292 	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
293 
294 	/* assign channels to AC97C channel A */
295 	switch (runtime->channels) {
296 	case 1:
297 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
298 		break;
299 	case 2:
300 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
301 			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
302 		break;
303 	default:
304 		/* TODO: support more than two channels */
305 		return -EINVAL;
306 	}
307 	ac97c_writel(chip, ICA, word);
308 
309 	/* configure sample format and size */
310 	word = ac97c_readl(chip, CAMR);
311 	if (chip->opened <= 1)
312 		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
313 	else
314 		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
315 
316 	switch (runtime->format) {
317 	case SNDRV_PCM_FORMAT_S16_LE:
318 		break;
319 	case SNDRV_PCM_FORMAT_S16_BE: /* fall through */
320 		word &= ~(AC97C_CMR_CEM_LITTLE);
321 		break;
322 	default:
323 		word = ac97c_readl(chip, ICA);
324 		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
325 		ac97c_writel(chip, ICA, word);
326 		return -EINVAL;
327 	}
328 
329 	/* Enable overrun interrupt on channel A */
330 	word |= AC97C_CSR_OVRUN;
331 
332 	ac97c_writel(chip, CAMR, word);
333 
334 	/* Enable channel A event interrupt */
335 	word = ac97c_readl(chip, IMR);
336 	word |= AC97C_SR_CAEVT;
337 	ac97c_writel(chip, IER, word);
338 
339 	/* set variable rate if needed */
340 	if (runtime->rate != 48000) {
341 		word = ac97c_readl(chip, MR);
342 		word |= AC97C_MR_VRA;
343 		ac97c_writel(chip, MR, word);
344 	} else {
345 		word = ac97c_readl(chip, MR);
346 		word &= ~(AC97C_MR_VRA);
347 		ac97c_writel(chip, MR, word);
348 	}
349 
350 	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_LR_ADC_RATE,
351 			runtime->rate);
352 	if (retval)
353 		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
354 				runtime->rate);
355 
356 	/* Initialize and start the PDC */
357 	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_RPR);
358 	writel(block_size / 2, chip->regs + ATMEL_PDC_RCR);
359 	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_RNPR);
360 	writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
361 
362 	return retval;
363 }
364 
365 static int
366 atmel_ac97c_playback_trigger(struct snd_pcm_substream *substream, int cmd)
367 {
368 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
369 	unsigned long camr, ptcr = 0;
370 
371 	camr = ac97c_readl(chip, CAMR);
372 
373 	switch (cmd) {
374 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: /* fall through */
375 	case SNDRV_PCM_TRIGGER_RESUME: /* fall through */
376 	case SNDRV_PCM_TRIGGER_START:
377 		ptcr = ATMEL_PDC_TXTEN;
378 		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDTX;
379 		break;
380 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH: /* fall through */
381 	case SNDRV_PCM_TRIGGER_SUSPEND: /* fall through */
382 	case SNDRV_PCM_TRIGGER_STOP:
383 		ptcr |= ATMEL_PDC_TXTDIS;
384 		if (chip->opened <= 1)
385 			camr &= ~AC97C_CMR_CENA;
386 		break;
387 	default:
388 		return -EINVAL;
389 	}
390 
391 	ac97c_writel(chip, CAMR, camr);
392 	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
393 	return 0;
394 }
395 
396 static int
397 atmel_ac97c_capture_trigger(struct snd_pcm_substream *substream, int cmd)
398 {
399 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
400 	unsigned long camr, ptcr = 0;
401 
402 	camr = ac97c_readl(chip, CAMR);
403 	ptcr = readl(chip->regs + ATMEL_PDC_PTSR);
404 
405 	switch (cmd) {
406 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: /* fall through */
407 	case SNDRV_PCM_TRIGGER_RESUME: /* fall through */
408 	case SNDRV_PCM_TRIGGER_START:
409 		ptcr = ATMEL_PDC_RXTEN;
410 		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDRX;
411 		break;
412 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH: /* fall through */
413 	case SNDRV_PCM_TRIGGER_SUSPEND: /* fall through */
414 	case SNDRV_PCM_TRIGGER_STOP:
415 		ptcr |= ATMEL_PDC_RXTDIS;
416 		if (chip->opened <= 1)
417 			camr &= ~AC97C_CMR_CENA;
418 		break;
419 	default:
420 		return -EINVAL;
421 	}
422 
423 	ac97c_writel(chip, CAMR, camr);
424 	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
425 	return 0;
426 }
427 
428 static snd_pcm_uframes_t
429 atmel_ac97c_playback_pointer(struct snd_pcm_substream *substream)
430 {
431 	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
432 	struct snd_pcm_runtime	*runtime = substream->runtime;
433 	snd_pcm_uframes_t	frames;
434 	unsigned long		bytes;
435 
436 	bytes = readl(chip->regs + ATMEL_PDC_TPR);
437 	bytes -= runtime->dma_addr;
438 
439 	frames = bytes_to_frames(runtime, bytes);
440 	if (frames >= runtime->buffer_size)
441 		frames -= runtime->buffer_size;
442 	return frames;
443 }
444 
445 static snd_pcm_uframes_t
446 atmel_ac97c_capture_pointer(struct snd_pcm_substream *substream)
447 {
448 	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
449 	struct snd_pcm_runtime	*runtime = substream->runtime;
450 	snd_pcm_uframes_t	frames;
451 	unsigned long		bytes;
452 
453 	bytes = readl(chip->regs + ATMEL_PDC_RPR);
454 	bytes -= runtime->dma_addr;
455 
456 	frames = bytes_to_frames(runtime, bytes);
457 	if (frames >= runtime->buffer_size)
458 		frames -= runtime->buffer_size;
459 	return frames;
460 }
461 
462 static const struct snd_pcm_ops atmel_ac97_playback_ops = {
463 	.open		= atmel_ac97c_playback_open,
464 	.close		= atmel_ac97c_playback_close,
465 	.ioctl		= snd_pcm_lib_ioctl,
466 	.hw_params	= atmel_ac97c_playback_hw_params,
467 	.hw_free	= snd_pcm_lib_free_pages,
468 	.prepare	= atmel_ac97c_playback_prepare,
469 	.trigger	= atmel_ac97c_playback_trigger,
470 	.pointer	= atmel_ac97c_playback_pointer,
471 };
472 
473 static const struct snd_pcm_ops atmel_ac97_capture_ops = {
474 	.open		= atmel_ac97c_capture_open,
475 	.close		= atmel_ac97c_capture_close,
476 	.ioctl		= snd_pcm_lib_ioctl,
477 	.hw_params	= atmel_ac97c_capture_hw_params,
478 	.hw_free	= snd_pcm_lib_free_pages,
479 	.prepare	= atmel_ac97c_capture_prepare,
480 	.trigger	= atmel_ac97c_capture_trigger,
481 	.pointer	= atmel_ac97c_capture_pointer,
482 };
483 
484 static irqreturn_t atmel_ac97c_interrupt(int irq, void *dev)
485 {
486 	struct atmel_ac97c	*chip  = (struct atmel_ac97c *)dev;
487 	irqreturn_t		retval = IRQ_NONE;
488 	u32			sr     = ac97c_readl(chip, SR);
489 	u32			casr   = ac97c_readl(chip, CASR);
490 	u32			cosr   = ac97c_readl(chip, COSR);
491 	u32			camr   = ac97c_readl(chip, CAMR);
492 
493 	if (sr & AC97C_SR_CAEVT) {
494 		struct snd_pcm_runtime *runtime;
495 		int offset, next_period, block_size;
496 		dev_dbg(&chip->pdev->dev, "channel A event%s%s%s%s%s%s\n",
497 				casr & AC97C_CSR_OVRUN   ? " OVRUN"   : "",
498 				casr & AC97C_CSR_RXRDY   ? " RXRDY"   : "",
499 				casr & AC97C_CSR_UNRUN   ? " UNRUN"   : "",
500 				casr & AC97C_CSR_TXEMPTY ? " TXEMPTY" : "",
501 				casr & AC97C_CSR_TXRDY   ? " TXRDY"   : "",
502 				!casr                    ? " NONE"    : "");
503 		if ((casr & camr) & AC97C_CSR_ENDTX) {
504 			runtime = chip->playback_substream->runtime;
505 			block_size = frames_to_bytes(runtime, runtime->period_size);
506 			chip->playback_period++;
507 
508 			if (chip->playback_period == runtime->periods)
509 				chip->playback_period = 0;
510 			next_period = chip->playback_period + 1;
511 			if (next_period == runtime->periods)
512 				next_period = 0;
513 
514 			offset = block_size * next_period;
515 
516 			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_TNPR);
517 			writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
518 
519 			snd_pcm_period_elapsed(chip->playback_substream);
520 		}
521 		if ((casr & camr) & AC97C_CSR_ENDRX) {
522 			runtime = chip->capture_substream->runtime;
523 			block_size = frames_to_bytes(runtime, runtime->period_size);
524 			chip->capture_period++;
525 
526 			if (chip->capture_period == runtime->periods)
527 				chip->capture_period = 0;
528 			next_period = chip->capture_period + 1;
529 			if (next_period == runtime->periods)
530 				next_period = 0;
531 
532 			offset = block_size * next_period;
533 
534 			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_RNPR);
535 			writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
536 			snd_pcm_period_elapsed(chip->capture_substream);
537 		}
538 		retval = IRQ_HANDLED;
539 	}
540 
541 	if (sr & AC97C_SR_COEVT) {
542 		dev_info(&chip->pdev->dev, "codec channel event%s%s%s%s%s\n",
543 				cosr & AC97C_CSR_OVRUN   ? " OVRUN"   : "",
544 				cosr & AC97C_CSR_RXRDY   ? " RXRDY"   : "",
545 				cosr & AC97C_CSR_TXEMPTY ? " TXEMPTY" : "",
546 				cosr & AC97C_CSR_TXRDY   ? " TXRDY"   : "",
547 				!cosr                    ? " NONE"    : "");
548 		retval = IRQ_HANDLED;
549 	}
550 
551 	if (retval == IRQ_NONE) {
552 		dev_err(&chip->pdev->dev, "spurious interrupt sr 0x%08x "
553 				"casr 0x%08x cosr 0x%08x\n", sr, casr, cosr);
554 	}
555 
556 	return retval;
557 }
558 
559 static const struct ac97_pcm at91_ac97_pcm_defs[] = {
560 	/* Playback */
561 	{
562 		.exclusive = 1,
563 		.r = { {
564 			.slots = ((1 << AC97_SLOT_PCM_LEFT)
565 				  | (1 << AC97_SLOT_PCM_RIGHT)),
566 		} },
567 	},
568 	/* PCM in */
569 	{
570 		.stream = 1,
571 		.exclusive = 1,
572 		.r = { {
573 			.slots = ((1 << AC97_SLOT_PCM_LEFT)
574 					| (1 << AC97_SLOT_PCM_RIGHT)),
575 		} }
576 	},
577 	/* Mic in */
578 	{
579 		.stream = 1,
580 		.exclusive = 1,
581 		.r = { {
582 			.slots = (1<<AC97_SLOT_MIC),
583 		} }
584 	},
585 };
586 
587 static int atmel_ac97c_pcm_new(struct atmel_ac97c *chip)
588 {
589 	struct snd_pcm		*pcm;
590 	struct snd_pcm_hardware	hw = atmel_ac97c_hw;
591 	int			retval;
592 
593 	retval = snd_ac97_pcm_assign(chip->ac97_bus,
594 				     ARRAY_SIZE(at91_ac97_pcm_defs),
595 				     at91_ac97_pcm_defs);
596 	if (retval)
597 		return retval;
598 
599 	retval = snd_pcm_new(chip->card, chip->card->shortname, 0, 1, 1, &pcm);
600 	if (retval)
601 		return retval;
602 
603 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &atmel_ac97_capture_ops);
604 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &atmel_ac97_playback_ops);
605 
606 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
607 			&chip->pdev->dev, hw.periods_min * hw.period_bytes_min,
608 			hw.buffer_bytes_max);
609 
610 	pcm->private_data = chip;
611 	pcm->info_flags = 0;
612 	strcpy(pcm->name, chip->card->shortname);
613 	chip->pcm = pcm;
614 
615 	return 0;
616 }
617 
618 static int atmel_ac97c_mixer_new(struct atmel_ac97c *chip)
619 {
620 	struct snd_ac97_template template;
621 	memset(&template, 0, sizeof(template));
622 	template.private_data = chip;
623 	return snd_ac97_mixer(chip->ac97_bus, &template, &chip->ac97);
624 }
625 
626 static void atmel_ac97c_write(struct snd_ac97 *ac97, unsigned short reg,
627 		unsigned short val)
628 {
629 	struct atmel_ac97c *chip = get_chip(ac97);
630 	unsigned long word;
631 	int timeout = 40;
632 
633 	word = (reg & 0x7f) << 16 | val;
634 
635 	do {
636 		if (ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) {
637 			ac97c_writel(chip, COTHR, word);
638 			return;
639 		}
640 		udelay(1);
641 	} while (--timeout);
642 
643 	dev_dbg(&chip->pdev->dev, "codec write timeout\n");
644 }
645 
646 static unsigned short atmel_ac97c_read(struct snd_ac97 *ac97,
647 		unsigned short reg)
648 {
649 	struct atmel_ac97c *chip = get_chip(ac97);
650 	unsigned long word;
651 	int timeout = 40;
652 	int write = 10;
653 
654 	word = (0x80 | (reg & 0x7f)) << 16;
655 
656 	if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0)
657 		ac97c_readl(chip, CORHR);
658 
659 retry_write:
660 	timeout = 40;
661 
662 	do {
663 		if ((ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) != 0) {
664 			ac97c_writel(chip, COTHR, word);
665 			goto read_reg;
666 		}
667 		udelay(10);
668 	} while (--timeout);
669 
670 	if (!--write)
671 		goto timed_out;
672 	goto retry_write;
673 
674 read_reg:
675 	do {
676 		if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0) {
677 			unsigned short val = ac97c_readl(chip, CORHR);
678 			return val;
679 		}
680 		udelay(10);
681 	} while (--timeout);
682 
683 	if (!--write)
684 		goto timed_out;
685 	goto retry_write;
686 
687 timed_out:
688 	dev_dbg(&chip->pdev->dev, "codec read timeout\n");
689 	return 0xffff;
690 }
691 
692 static void atmel_ac97c_reset(struct atmel_ac97c *chip)
693 {
694 	ac97c_writel(chip, MR,   0);
695 	ac97c_writel(chip, MR,   AC97C_MR_ENA);
696 	ac97c_writel(chip, CAMR, 0);
697 	ac97c_writel(chip, COMR, 0);
698 
699 	if (!IS_ERR(chip->reset_pin)) {
700 		gpiod_set_value(chip->reset_pin, 0);
701 		/* AC97 v2.2 specifications says minimum 1 us. */
702 		udelay(2);
703 		gpiod_set_value(chip->reset_pin, 1);
704 	} else {
705 		ac97c_writel(chip, MR, AC97C_MR_WRST | AC97C_MR_ENA);
706 		udelay(2);
707 		ac97c_writel(chip, MR, AC97C_MR_ENA);
708 	}
709 }
710 
711 static const struct of_device_id atmel_ac97c_dt_ids[] = {
712 	{ .compatible = "atmel,at91sam9263-ac97c", },
713 	{ }
714 };
715 MODULE_DEVICE_TABLE(of, atmel_ac97c_dt_ids);
716 
717 static int atmel_ac97c_probe(struct platform_device *pdev)
718 {
719 	struct device			*dev = &pdev->dev;
720 	struct snd_card			*card;
721 	struct atmel_ac97c		*chip;
722 	struct resource			*regs;
723 	struct clk			*pclk;
724 	static struct snd_ac97_bus_ops	ops = {
725 		.write	= atmel_ac97c_write,
726 		.read	= atmel_ac97c_read,
727 	};
728 	int				retval;
729 	int				irq;
730 
731 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
732 	if (!regs) {
733 		dev_dbg(&pdev->dev, "no memory resource\n");
734 		return -ENXIO;
735 	}
736 
737 	irq = platform_get_irq(pdev, 0);
738 	if (irq < 0) {
739 		dev_dbg(&pdev->dev, "could not get irq: %d\n", irq);
740 		return irq;
741 	}
742 
743 	pclk = clk_get(&pdev->dev, "ac97_clk");
744 	if (IS_ERR(pclk)) {
745 		dev_dbg(&pdev->dev, "no peripheral clock\n");
746 		return PTR_ERR(pclk);
747 	}
748 	retval = clk_prepare_enable(pclk);
749 	if (retval)
750 		goto err_prepare_enable;
751 
752 	retval = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1,
753 			      SNDRV_DEFAULT_STR1, THIS_MODULE,
754 			      sizeof(struct atmel_ac97c), &card);
755 	if (retval) {
756 		dev_dbg(&pdev->dev, "could not create sound card device\n");
757 		goto err_snd_card_new;
758 	}
759 
760 	chip = get_chip(card);
761 
762 	retval = request_irq(irq, atmel_ac97c_interrupt, 0, "AC97C", chip);
763 	if (retval) {
764 		dev_dbg(&pdev->dev, "unable to request irq %d\n", irq);
765 		goto err_request_irq;
766 	}
767 	chip->irq = irq;
768 
769 	spin_lock_init(&chip->lock);
770 
771 	strcpy(card->driver, "Atmel AC97C");
772 	strcpy(card->shortname, "Atmel AC97C");
773 	sprintf(card->longname, "Atmel AC97 controller");
774 
775 	chip->card = card;
776 	chip->pclk = pclk;
777 	chip->pdev = pdev;
778 	chip->regs = ioremap(regs->start, resource_size(regs));
779 
780 	if (!chip->regs) {
781 		dev_dbg(&pdev->dev, "could not remap register memory\n");
782 		retval = -ENOMEM;
783 		goto err_ioremap;
784 	}
785 
786 	chip->reset_pin = devm_gpiod_get_index(dev, "ac97", 2, GPIOD_OUT_HIGH);
787 	if (IS_ERR(chip->reset_pin))
788 		dev_dbg(dev, "reset pin not available\n");
789 
790 	atmel_ac97c_reset(chip);
791 
792 	/* Enable overrun interrupt from codec channel */
793 	ac97c_writel(chip, COMR, AC97C_CSR_OVRUN);
794 	ac97c_writel(chip, IER, ac97c_readl(chip, IMR) | AC97C_SR_COEVT);
795 
796 	retval = snd_ac97_bus(card, 0, &ops, chip, &chip->ac97_bus);
797 	if (retval) {
798 		dev_dbg(&pdev->dev, "could not register on ac97 bus\n");
799 		goto err_ac97_bus;
800 	}
801 
802 	retval = atmel_ac97c_mixer_new(chip);
803 	if (retval) {
804 		dev_dbg(&pdev->dev, "could not register ac97 mixer\n");
805 		goto err_ac97_bus;
806 	}
807 
808 	retval = atmel_ac97c_pcm_new(chip);
809 	if (retval) {
810 		dev_dbg(&pdev->dev, "could not register ac97 pcm device\n");
811 		goto err_ac97_bus;
812 	}
813 
814 	retval = snd_card_register(card);
815 	if (retval) {
816 		dev_dbg(&pdev->dev, "could not register sound card\n");
817 		goto err_ac97_bus;
818 	}
819 
820 	platform_set_drvdata(pdev, card);
821 
822 	dev_info(&pdev->dev, "Atmel AC97 controller at 0x%p, irq = %d\n",
823 			chip->regs, irq);
824 
825 	return 0;
826 
827 err_ac97_bus:
828 	iounmap(chip->regs);
829 err_ioremap:
830 	free_irq(irq, chip);
831 err_request_irq:
832 	snd_card_free(card);
833 err_snd_card_new:
834 	clk_disable_unprepare(pclk);
835 err_prepare_enable:
836 	clk_put(pclk);
837 	return retval;
838 }
839 
840 #ifdef CONFIG_PM_SLEEP
841 static int atmel_ac97c_suspend(struct device *pdev)
842 {
843 	struct snd_card *card = dev_get_drvdata(pdev);
844 	struct atmel_ac97c *chip = card->private_data;
845 
846 	clk_disable_unprepare(chip->pclk);
847 	return 0;
848 }
849 
850 static int atmel_ac97c_resume(struct device *pdev)
851 {
852 	struct snd_card *card = dev_get_drvdata(pdev);
853 	struct atmel_ac97c *chip = card->private_data;
854 	int ret = clk_prepare_enable(chip->pclk);
855 
856 	return ret;
857 }
858 
859 static SIMPLE_DEV_PM_OPS(atmel_ac97c_pm, atmel_ac97c_suspend, atmel_ac97c_resume);
860 #define ATMEL_AC97C_PM_OPS	&atmel_ac97c_pm
861 #else
862 #define ATMEL_AC97C_PM_OPS	NULL
863 #endif
864 
865 static int atmel_ac97c_remove(struct platform_device *pdev)
866 {
867 	struct snd_card *card = platform_get_drvdata(pdev);
868 	struct atmel_ac97c *chip = get_chip(card);
869 
870 	ac97c_writel(chip, CAMR, 0);
871 	ac97c_writel(chip, COMR, 0);
872 	ac97c_writel(chip, MR,   0);
873 
874 	clk_disable_unprepare(chip->pclk);
875 	clk_put(chip->pclk);
876 	iounmap(chip->regs);
877 	free_irq(chip->irq, chip);
878 
879 	snd_card_free(card);
880 
881 	return 0;
882 }
883 
884 static struct platform_driver atmel_ac97c_driver = {
885 	.probe		= atmel_ac97c_probe,
886 	.remove		= atmel_ac97c_remove,
887 	.driver		= {
888 		.name	= "atmel_ac97c",
889 		.pm	= ATMEL_AC97C_PM_OPS,
890 		.of_match_table = atmel_ac97c_dt_ids,
891 	},
892 };
893 module_platform_driver(atmel_ac97c_driver);
894 
895 MODULE_LICENSE("GPL");
896 MODULE_DESCRIPTION("Driver for Atmel AC97 controller");
897 MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
898