xref: /openbmc/linux/sound/atmel/ac97c.c (revision 67bf4745)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for Atmel AC97C
4  *
5  * Copyright (C) 2005-2009 Atmel Corporation
6  */
7 #include <linux/clk.h>
8 #include <linux/delay.h>
9 #include <linux/bitmap.h>
10 #include <linux/device.h>
11 #include <linux/atmel_pdc.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 #include <linux/mutex.h>
18 #include <linux/types.h>
19 #include <linux/io.h>
20 #include <linux/of.h>
21 #include <linux/of_device.h>
22 
23 #include <sound/core.h>
24 #include <sound/initval.h>
25 #include <sound/pcm.h>
26 #include <sound/pcm_params.h>
27 #include <sound/ac97_codec.h>
28 #include <sound/memalloc.h>
29 
30 #include "ac97c.h"
31 
32 /* Serialize access to opened variable */
33 static DEFINE_MUTEX(opened_mutex);
34 
35 struct atmel_ac97c {
36 	struct clk			*pclk;
37 	struct platform_device		*pdev;
38 
39 	struct snd_pcm_substream	*playback_substream;
40 	struct snd_pcm_substream	*capture_substream;
41 	struct snd_card			*card;
42 	struct snd_pcm			*pcm;
43 	struct snd_ac97			*ac97;
44 	struct snd_ac97_bus		*ac97_bus;
45 
46 	u64				cur_format;
47 	unsigned int			cur_rate;
48 	int				playback_period, capture_period;
49 	/* Serialize access to opened variable */
50 	spinlock_t			lock;
51 	void __iomem			*regs;
52 	int				irq;
53 	int				opened;
54 	struct gpio_desc		*reset_pin;
55 };
56 
57 #define get_chip(card) ((struct atmel_ac97c *)(card)->private_data)
58 
59 #define ac97c_writel(chip, reg, val)			\
60 	__raw_writel((val), (chip)->regs + AC97C_##reg)
61 #define ac97c_readl(chip, reg)				\
62 	__raw_readl((chip)->regs + AC97C_##reg)
63 
64 static const struct snd_pcm_hardware atmel_ac97c_hw = {
65 	.info			= (SNDRV_PCM_INFO_MMAP
66 				  | SNDRV_PCM_INFO_MMAP_VALID
67 				  | SNDRV_PCM_INFO_INTERLEAVED
68 				  | SNDRV_PCM_INFO_BLOCK_TRANSFER
69 				  | SNDRV_PCM_INFO_JOINT_DUPLEX
70 				  | SNDRV_PCM_INFO_RESUME
71 				  | SNDRV_PCM_INFO_PAUSE),
72 	.formats		= (SNDRV_PCM_FMTBIT_S16_BE
73 				  | SNDRV_PCM_FMTBIT_S16_LE),
74 	.rates			= (SNDRV_PCM_RATE_CONTINUOUS),
75 	.rate_min		= 4000,
76 	.rate_max		= 48000,
77 	.channels_min		= 1,
78 	.channels_max		= 2,
79 	.buffer_bytes_max	= 2 * 2 * 64 * 2048,
80 	.period_bytes_min	= 4096,
81 	.period_bytes_max	= 4096,
82 	.periods_min		= 6,
83 	.periods_max		= 64,
84 };
85 
86 static int atmel_ac97c_playback_open(struct snd_pcm_substream *substream)
87 {
88 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
89 	struct snd_pcm_runtime *runtime = substream->runtime;
90 
91 	mutex_lock(&opened_mutex);
92 	chip->opened++;
93 	runtime->hw = atmel_ac97c_hw;
94 	if (chip->cur_rate) {
95 		runtime->hw.rate_min = chip->cur_rate;
96 		runtime->hw.rate_max = chip->cur_rate;
97 	}
98 	if (chip->cur_format)
99 		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
100 	mutex_unlock(&opened_mutex);
101 	chip->playback_substream = substream;
102 	return 0;
103 }
104 
105 static int atmel_ac97c_capture_open(struct snd_pcm_substream *substream)
106 {
107 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
108 	struct snd_pcm_runtime *runtime = substream->runtime;
109 
110 	mutex_lock(&opened_mutex);
111 	chip->opened++;
112 	runtime->hw = atmel_ac97c_hw;
113 	if (chip->cur_rate) {
114 		runtime->hw.rate_min = chip->cur_rate;
115 		runtime->hw.rate_max = chip->cur_rate;
116 	}
117 	if (chip->cur_format)
118 		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
119 	mutex_unlock(&opened_mutex);
120 	chip->capture_substream = substream;
121 	return 0;
122 }
123 
124 static int atmel_ac97c_playback_close(struct snd_pcm_substream *substream)
125 {
126 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
127 
128 	mutex_lock(&opened_mutex);
129 	chip->opened--;
130 	if (!chip->opened) {
131 		chip->cur_rate = 0;
132 		chip->cur_format = 0;
133 	}
134 	mutex_unlock(&opened_mutex);
135 
136 	chip->playback_substream = NULL;
137 
138 	return 0;
139 }
140 
141 static int atmel_ac97c_capture_close(struct snd_pcm_substream *substream)
142 {
143 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
144 
145 	mutex_lock(&opened_mutex);
146 	chip->opened--;
147 	if (!chip->opened) {
148 		chip->cur_rate = 0;
149 		chip->cur_format = 0;
150 	}
151 	mutex_unlock(&opened_mutex);
152 
153 	chip->capture_substream = NULL;
154 
155 	return 0;
156 }
157 
158 static int atmel_ac97c_playback_hw_params(struct snd_pcm_substream *substream,
159 		struct snd_pcm_hw_params *hw_params)
160 {
161 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
162 	int retval;
163 
164 	retval = snd_pcm_lib_malloc_pages(substream,
165 					params_buffer_bytes(hw_params));
166 	if (retval < 0)
167 		return retval;
168 
169 	/* Set restrictions to params. */
170 	mutex_lock(&opened_mutex);
171 	chip->cur_rate = params_rate(hw_params);
172 	chip->cur_format = params_format(hw_params);
173 	mutex_unlock(&opened_mutex);
174 
175 	return retval;
176 }
177 
178 static int atmel_ac97c_capture_hw_params(struct snd_pcm_substream *substream,
179 		struct snd_pcm_hw_params *hw_params)
180 {
181 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
182 	int retval;
183 
184 	retval = snd_pcm_lib_malloc_pages(substream,
185 					params_buffer_bytes(hw_params));
186 	if (retval < 0)
187 		return retval;
188 
189 	/* Set restrictions to params. */
190 	mutex_lock(&opened_mutex);
191 	chip->cur_rate = params_rate(hw_params);
192 	chip->cur_format = params_format(hw_params);
193 	mutex_unlock(&opened_mutex);
194 
195 	return retval;
196 }
197 
198 static int atmel_ac97c_playback_prepare(struct snd_pcm_substream *substream)
199 {
200 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
201 	struct snd_pcm_runtime *runtime = substream->runtime;
202 	int block_size = frames_to_bytes(runtime, runtime->period_size);
203 	unsigned long word = ac97c_readl(chip, OCA);
204 	int retval;
205 
206 	chip->playback_period = 0;
207 	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
208 
209 	/* assign channels to AC97C channel A */
210 	switch (runtime->channels) {
211 	case 1:
212 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
213 		break;
214 	case 2:
215 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
216 			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
217 		break;
218 	default:
219 		/* TODO: support more than two channels */
220 		return -EINVAL;
221 	}
222 	ac97c_writel(chip, OCA, word);
223 
224 	/* configure sample format and size */
225 	word = ac97c_readl(chip, CAMR);
226 	if (chip->opened <= 1)
227 		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
228 	else
229 		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
230 
231 	switch (runtime->format) {
232 	case SNDRV_PCM_FORMAT_S16_LE:
233 		break;
234 	case SNDRV_PCM_FORMAT_S16_BE: /* fall through */
235 		word &= ~(AC97C_CMR_CEM_LITTLE);
236 		break;
237 	default:
238 		word = ac97c_readl(chip, OCA);
239 		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
240 		ac97c_writel(chip, OCA, word);
241 		return -EINVAL;
242 	}
243 
244 	/* Enable underrun interrupt on channel A */
245 	word |= AC97C_CSR_UNRUN;
246 
247 	ac97c_writel(chip, CAMR, word);
248 
249 	/* Enable channel A event interrupt */
250 	word = ac97c_readl(chip, IMR);
251 	word |= AC97C_SR_CAEVT;
252 	ac97c_writel(chip, IER, word);
253 
254 	/* set variable rate if needed */
255 	if (runtime->rate != 48000) {
256 		word = ac97c_readl(chip, MR);
257 		word |= AC97C_MR_VRA;
258 		ac97c_writel(chip, MR, word);
259 	} else {
260 		word = ac97c_readl(chip, MR);
261 		word &= ~(AC97C_MR_VRA);
262 		ac97c_writel(chip, MR, word);
263 	}
264 
265 	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_FRONT_DAC_RATE,
266 			runtime->rate);
267 	if (retval)
268 		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
269 				runtime->rate);
270 
271 	/* Initialize and start the PDC */
272 	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_TPR);
273 	writel(block_size / 2, chip->regs + ATMEL_PDC_TCR);
274 	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_TNPR);
275 	writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
276 
277 	return retval;
278 }
279 
280 static int atmel_ac97c_capture_prepare(struct snd_pcm_substream *substream)
281 {
282 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
283 	struct snd_pcm_runtime *runtime = substream->runtime;
284 	int block_size = frames_to_bytes(runtime, runtime->period_size);
285 	unsigned long word = ac97c_readl(chip, ICA);
286 	int retval;
287 
288 	chip->capture_period = 0;
289 	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
290 
291 	/* assign channels to AC97C channel A */
292 	switch (runtime->channels) {
293 	case 1:
294 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
295 		break;
296 	case 2:
297 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
298 			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
299 		break;
300 	default:
301 		/* TODO: support more than two channels */
302 		return -EINVAL;
303 	}
304 	ac97c_writel(chip, ICA, word);
305 
306 	/* configure sample format and size */
307 	word = ac97c_readl(chip, CAMR);
308 	if (chip->opened <= 1)
309 		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
310 	else
311 		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
312 
313 	switch (runtime->format) {
314 	case SNDRV_PCM_FORMAT_S16_LE:
315 		break;
316 	case SNDRV_PCM_FORMAT_S16_BE: /* fall through */
317 		word &= ~(AC97C_CMR_CEM_LITTLE);
318 		break;
319 	default:
320 		word = ac97c_readl(chip, ICA);
321 		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
322 		ac97c_writel(chip, ICA, word);
323 		return -EINVAL;
324 	}
325 
326 	/* Enable overrun interrupt on channel A */
327 	word |= AC97C_CSR_OVRUN;
328 
329 	ac97c_writel(chip, CAMR, word);
330 
331 	/* Enable channel A event interrupt */
332 	word = ac97c_readl(chip, IMR);
333 	word |= AC97C_SR_CAEVT;
334 	ac97c_writel(chip, IER, word);
335 
336 	/* set variable rate if needed */
337 	if (runtime->rate != 48000) {
338 		word = ac97c_readl(chip, MR);
339 		word |= AC97C_MR_VRA;
340 		ac97c_writel(chip, MR, word);
341 	} else {
342 		word = ac97c_readl(chip, MR);
343 		word &= ~(AC97C_MR_VRA);
344 		ac97c_writel(chip, MR, word);
345 	}
346 
347 	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_LR_ADC_RATE,
348 			runtime->rate);
349 	if (retval)
350 		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
351 				runtime->rate);
352 
353 	/* Initialize and start the PDC */
354 	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_RPR);
355 	writel(block_size / 2, chip->regs + ATMEL_PDC_RCR);
356 	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_RNPR);
357 	writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
358 
359 	return retval;
360 }
361 
362 static int
363 atmel_ac97c_playback_trigger(struct snd_pcm_substream *substream, int cmd)
364 {
365 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
366 	unsigned long camr, ptcr = 0;
367 
368 	camr = ac97c_readl(chip, CAMR);
369 
370 	switch (cmd) {
371 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: /* fall through */
372 	case SNDRV_PCM_TRIGGER_RESUME: /* fall through */
373 	case SNDRV_PCM_TRIGGER_START:
374 		ptcr = ATMEL_PDC_TXTEN;
375 		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDTX;
376 		break;
377 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH: /* fall through */
378 	case SNDRV_PCM_TRIGGER_SUSPEND: /* fall through */
379 	case SNDRV_PCM_TRIGGER_STOP:
380 		ptcr |= ATMEL_PDC_TXTDIS;
381 		if (chip->opened <= 1)
382 			camr &= ~AC97C_CMR_CENA;
383 		break;
384 	default:
385 		return -EINVAL;
386 	}
387 
388 	ac97c_writel(chip, CAMR, camr);
389 	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
390 	return 0;
391 }
392 
393 static int
394 atmel_ac97c_capture_trigger(struct snd_pcm_substream *substream, int cmd)
395 {
396 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
397 	unsigned long camr, ptcr = 0;
398 
399 	camr = ac97c_readl(chip, CAMR);
400 	ptcr = readl(chip->regs + ATMEL_PDC_PTSR);
401 
402 	switch (cmd) {
403 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: /* fall through */
404 	case SNDRV_PCM_TRIGGER_RESUME: /* fall through */
405 	case SNDRV_PCM_TRIGGER_START:
406 		ptcr = ATMEL_PDC_RXTEN;
407 		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDRX;
408 		break;
409 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH: /* fall through */
410 	case SNDRV_PCM_TRIGGER_SUSPEND: /* fall through */
411 	case SNDRV_PCM_TRIGGER_STOP:
412 		ptcr |= ATMEL_PDC_RXTDIS;
413 		if (chip->opened <= 1)
414 			camr &= ~AC97C_CMR_CENA;
415 		break;
416 	default:
417 		return -EINVAL;
418 	}
419 
420 	ac97c_writel(chip, CAMR, camr);
421 	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
422 	return 0;
423 }
424 
425 static snd_pcm_uframes_t
426 atmel_ac97c_playback_pointer(struct snd_pcm_substream *substream)
427 {
428 	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
429 	struct snd_pcm_runtime	*runtime = substream->runtime;
430 	snd_pcm_uframes_t	frames;
431 	unsigned long		bytes;
432 
433 	bytes = readl(chip->regs + ATMEL_PDC_TPR);
434 	bytes -= runtime->dma_addr;
435 
436 	frames = bytes_to_frames(runtime, bytes);
437 	if (frames >= runtime->buffer_size)
438 		frames -= runtime->buffer_size;
439 	return frames;
440 }
441 
442 static snd_pcm_uframes_t
443 atmel_ac97c_capture_pointer(struct snd_pcm_substream *substream)
444 {
445 	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
446 	struct snd_pcm_runtime	*runtime = substream->runtime;
447 	snd_pcm_uframes_t	frames;
448 	unsigned long		bytes;
449 
450 	bytes = readl(chip->regs + ATMEL_PDC_RPR);
451 	bytes -= runtime->dma_addr;
452 
453 	frames = bytes_to_frames(runtime, bytes);
454 	if (frames >= runtime->buffer_size)
455 		frames -= runtime->buffer_size;
456 	return frames;
457 }
458 
459 static const struct snd_pcm_ops atmel_ac97_playback_ops = {
460 	.open		= atmel_ac97c_playback_open,
461 	.close		= atmel_ac97c_playback_close,
462 	.ioctl		= snd_pcm_lib_ioctl,
463 	.hw_params	= atmel_ac97c_playback_hw_params,
464 	.hw_free	= snd_pcm_lib_free_pages,
465 	.prepare	= atmel_ac97c_playback_prepare,
466 	.trigger	= atmel_ac97c_playback_trigger,
467 	.pointer	= atmel_ac97c_playback_pointer,
468 };
469 
470 static const struct snd_pcm_ops atmel_ac97_capture_ops = {
471 	.open		= atmel_ac97c_capture_open,
472 	.close		= atmel_ac97c_capture_close,
473 	.ioctl		= snd_pcm_lib_ioctl,
474 	.hw_params	= atmel_ac97c_capture_hw_params,
475 	.hw_free	= snd_pcm_lib_free_pages,
476 	.prepare	= atmel_ac97c_capture_prepare,
477 	.trigger	= atmel_ac97c_capture_trigger,
478 	.pointer	= atmel_ac97c_capture_pointer,
479 };
480 
481 static irqreturn_t atmel_ac97c_interrupt(int irq, void *dev)
482 {
483 	struct atmel_ac97c	*chip  = (struct atmel_ac97c *)dev;
484 	irqreturn_t		retval = IRQ_NONE;
485 	u32			sr     = ac97c_readl(chip, SR);
486 	u32			casr   = ac97c_readl(chip, CASR);
487 	u32			cosr   = ac97c_readl(chip, COSR);
488 	u32			camr   = ac97c_readl(chip, CAMR);
489 
490 	if (sr & AC97C_SR_CAEVT) {
491 		struct snd_pcm_runtime *runtime;
492 		int offset, next_period, block_size;
493 		dev_dbg(&chip->pdev->dev, "channel A event%s%s%s%s%s%s\n",
494 				casr & AC97C_CSR_OVRUN   ? " OVRUN"   : "",
495 				casr & AC97C_CSR_RXRDY   ? " RXRDY"   : "",
496 				casr & AC97C_CSR_UNRUN   ? " UNRUN"   : "",
497 				casr & AC97C_CSR_TXEMPTY ? " TXEMPTY" : "",
498 				casr & AC97C_CSR_TXRDY   ? " TXRDY"   : "",
499 				!casr                    ? " NONE"    : "");
500 		if ((casr & camr) & AC97C_CSR_ENDTX) {
501 			runtime = chip->playback_substream->runtime;
502 			block_size = frames_to_bytes(runtime, runtime->period_size);
503 			chip->playback_period++;
504 
505 			if (chip->playback_period == runtime->periods)
506 				chip->playback_period = 0;
507 			next_period = chip->playback_period + 1;
508 			if (next_period == runtime->periods)
509 				next_period = 0;
510 
511 			offset = block_size * next_period;
512 
513 			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_TNPR);
514 			writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
515 
516 			snd_pcm_period_elapsed(chip->playback_substream);
517 		}
518 		if ((casr & camr) & AC97C_CSR_ENDRX) {
519 			runtime = chip->capture_substream->runtime;
520 			block_size = frames_to_bytes(runtime, runtime->period_size);
521 			chip->capture_period++;
522 
523 			if (chip->capture_period == runtime->periods)
524 				chip->capture_period = 0;
525 			next_period = chip->capture_period + 1;
526 			if (next_period == runtime->periods)
527 				next_period = 0;
528 
529 			offset = block_size * next_period;
530 
531 			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_RNPR);
532 			writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
533 			snd_pcm_period_elapsed(chip->capture_substream);
534 		}
535 		retval = IRQ_HANDLED;
536 	}
537 
538 	if (sr & AC97C_SR_COEVT) {
539 		dev_info(&chip->pdev->dev, "codec channel event%s%s%s%s%s\n",
540 				cosr & AC97C_CSR_OVRUN   ? " OVRUN"   : "",
541 				cosr & AC97C_CSR_RXRDY   ? " RXRDY"   : "",
542 				cosr & AC97C_CSR_TXEMPTY ? " TXEMPTY" : "",
543 				cosr & AC97C_CSR_TXRDY   ? " TXRDY"   : "",
544 				!cosr                    ? " NONE"    : "");
545 		retval = IRQ_HANDLED;
546 	}
547 
548 	if (retval == IRQ_NONE) {
549 		dev_err(&chip->pdev->dev, "spurious interrupt sr 0x%08x "
550 				"casr 0x%08x cosr 0x%08x\n", sr, casr, cosr);
551 	}
552 
553 	return retval;
554 }
555 
556 static const struct ac97_pcm at91_ac97_pcm_defs[] = {
557 	/* Playback */
558 	{
559 		.exclusive = 1,
560 		.r = { {
561 			.slots = ((1 << AC97_SLOT_PCM_LEFT)
562 				  | (1 << AC97_SLOT_PCM_RIGHT)),
563 		} },
564 	},
565 	/* PCM in */
566 	{
567 		.stream = 1,
568 		.exclusive = 1,
569 		.r = { {
570 			.slots = ((1 << AC97_SLOT_PCM_LEFT)
571 					| (1 << AC97_SLOT_PCM_RIGHT)),
572 		} }
573 	},
574 	/* Mic in */
575 	{
576 		.stream = 1,
577 		.exclusive = 1,
578 		.r = { {
579 			.slots = (1<<AC97_SLOT_MIC),
580 		} }
581 	},
582 };
583 
584 static int atmel_ac97c_pcm_new(struct atmel_ac97c *chip)
585 {
586 	struct snd_pcm		*pcm;
587 	struct snd_pcm_hardware	hw = atmel_ac97c_hw;
588 	int			retval;
589 
590 	retval = snd_ac97_pcm_assign(chip->ac97_bus,
591 				     ARRAY_SIZE(at91_ac97_pcm_defs),
592 				     at91_ac97_pcm_defs);
593 	if (retval)
594 		return retval;
595 
596 	retval = snd_pcm_new(chip->card, chip->card->shortname, 0, 1, 1, &pcm);
597 	if (retval)
598 		return retval;
599 
600 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &atmel_ac97_capture_ops);
601 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &atmel_ac97_playback_ops);
602 
603 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
604 			&chip->pdev->dev, hw.periods_min * hw.period_bytes_min,
605 			hw.buffer_bytes_max);
606 
607 	pcm->private_data = chip;
608 	pcm->info_flags = 0;
609 	strcpy(pcm->name, chip->card->shortname);
610 	chip->pcm = pcm;
611 
612 	return 0;
613 }
614 
615 static int atmel_ac97c_mixer_new(struct atmel_ac97c *chip)
616 {
617 	struct snd_ac97_template template;
618 	memset(&template, 0, sizeof(template));
619 	template.private_data = chip;
620 	return snd_ac97_mixer(chip->ac97_bus, &template, &chip->ac97);
621 }
622 
623 static void atmel_ac97c_write(struct snd_ac97 *ac97, unsigned short reg,
624 		unsigned short val)
625 {
626 	struct atmel_ac97c *chip = get_chip(ac97);
627 	unsigned long word;
628 	int timeout = 40;
629 
630 	word = (reg & 0x7f) << 16 | val;
631 
632 	do {
633 		if (ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) {
634 			ac97c_writel(chip, COTHR, word);
635 			return;
636 		}
637 		udelay(1);
638 	} while (--timeout);
639 
640 	dev_dbg(&chip->pdev->dev, "codec write timeout\n");
641 }
642 
643 static unsigned short atmel_ac97c_read(struct snd_ac97 *ac97,
644 		unsigned short reg)
645 {
646 	struct atmel_ac97c *chip = get_chip(ac97);
647 	unsigned long word;
648 	int timeout = 40;
649 	int write = 10;
650 
651 	word = (0x80 | (reg & 0x7f)) << 16;
652 
653 	if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0)
654 		ac97c_readl(chip, CORHR);
655 
656 retry_write:
657 	timeout = 40;
658 
659 	do {
660 		if ((ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) != 0) {
661 			ac97c_writel(chip, COTHR, word);
662 			goto read_reg;
663 		}
664 		udelay(10);
665 	} while (--timeout);
666 
667 	if (!--write)
668 		goto timed_out;
669 	goto retry_write;
670 
671 read_reg:
672 	do {
673 		if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0) {
674 			unsigned short val = ac97c_readl(chip, CORHR);
675 			return val;
676 		}
677 		udelay(10);
678 	} while (--timeout);
679 
680 	if (!--write)
681 		goto timed_out;
682 	goto retry_write;
683 
684 timed_out:
685 	dev_dbg(&chip->pdev->dev, "codec read timeout\n");
686 	return 0xffff;
687 }
688 
689 static void atmel_ac97c_reset(struct atmel_ac97c *chip)
690 {
691 	ac97c_writel(chip, MR,   0);
692 	ac97c_writel(chip, MR,   AC97C_MR_ENA);
693 	ac97c_writel(chip, CAMR, 0);
694 	ac97c_writel(chip, COMR, 0);
695 
696 	if (!IS_ERR(chip->reset_pin)) {
697 		gpiod_set_value(chip->reset_pin, 0);
698 		/* AC97 v2.2 specifications says minimum 1 us. */
699 		udelay(2);
700 		gpiod_set_value(chip->reset_pin, 1);
701 	} else {
702 		ac97c_writel(chip, MR, AC97C_MR_WRST | AC97C_MR_ENA);
703 		udelay(2);
704 		ac97c_writel(chip, MR, AC97C_MR_ENA);
705 	}
706 }
707 
708 static const struct of_device_id atmel_ac97c_dt_ids[] = {
709 	{ .compatible = "atmel,at91sam9263-ac97c", },
710 	{ }
711 };
712 MODULE_DEVICE_TABLE(of, atmel_ac97c_dt_ids);
713 
714 static int atmel_ac97c_probe(struct platform_device *pdev)
715 {
716 	struct device			*dev = &pdev->dev;
717 	struct snd_card			*card;
718 	struct atmel_ac97c		*chip;
719 	struct resource			*regs;
720 	struct clk			*pclk;
721 	static struct snd_ac97_bus_ops	ops = {
722 		.write	= atmel_ac97c_write,
723 		.read	= atmel_ac97c_read,
724 	};
725 	int				retval;
726 	int				irq;
727 
728 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
729 	if (!regs) {
730 		dev_dbg(&pdev->dev, "no memory resource\n");
731 		return -ENXIO;
732 	}
733 
734 	irq = platform_get_irq(pdev, 0);
735 	if (irq < 0) {
736 		dev_dbg(&pdev->dev, "could not get irq: %d\n", irq);
737 		return irq;
738 	}
739 
740 	pclk = clk_get(&pdev->dev, "ac97_clk");
741 	if (IS_ERR(pclk)) {
742 		dev_dbg(&pdev->dev, "no peripheral clock\n");
743 		return PTR_ERR(pclk);
744 	}
745 	retval = clk_prepare_enable(pclk);
746 	if (retval)
747 		goto err_prepare_enable;
748 
749 	retval = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1,
750 			      SNDRV_DEFAULT_STR1, THIS_MODULE,
751 			      sizeof(struct atmel_ac97c), &card);
752 	if (retval) {
753 		dev_dbg(&pdev->dev, "could not create sound card device\n");
754 		goto err_snd_card_new;
755 	}
756 
757 	chip = get_chip(card);
758 
759 	retval = request_irq(irq, atmel_ac97c_interrupt, 0, "AC97C", chip);
760 	if (retval) {
761 		dev_dbg(&pdev->dev, "unable to request irq %d\n", irq);
762 		goto err_request_irq;
763 	}
764 	chip->irq = irq;
765 
766 	spin_lock_init(&chip->lock);
767 
768 	strcpy(card->driver, "Atmel AC97C");
769 	strcpy(card->shortname, "Atmel AC97C");
770 	sprintf(card->longname, "Atmel AC97 controller");
771 
772 	chip->card = card;
773 	chip->pclk = pclk;
774 	chip->pdev = pdev;
775 	chip->regs = ioremap(regs->start, resource_size(regs));
776 
777 	if (!chip->regs) {
778 		dev_dbg(&pdev->dev, "could not remap register memory\n");
779 		retval = -ENOMEM;
780 		goto err_ioremap;
781 	}
782 
783 	chip->reset_pin = devm_gpiod_get_index(dev, "ac97", 2, GPIOD_OUT_HIGH);
784 	if (IS_ERR(chip->reset_pin))
785 		dev_dbg(dev, "reset pin not available\n");
786 
787 	atmel_ac97c_reset(chip);
788 
789 	/* Enable overrun interrupt from codec channel */
790 	ac97c_writel(chip, COMR, AC97C_CSR_OVRUN);
791 	ac97c_writel(chip, IER, ac97c_readl(chip, IMR) | AC97C_SR_COEVT);
792 
793 	retval = snd_ac97_bus(card, 0, &ops, chip, &chip->ac97_bus);
794 	if (retval) {
795 		dev_dbg(&pdev->dev, "could not register on ac97 bus\n");
796 		goto err_ac97_bus;
797 	}
798 
799 	retval = atmel_ac97c_mixer_new(chip);
800 	if (retval) {
801 		dev_dbg(&pdev->dev, "could not register ac97 mixer\n");
802 		goto err_ac97_bus;
803 	}
804 
805 	retval = atmel_ac97c_pcm_new(chip);
806 	if (retval) {
807 		dev_dbg(&pdev->dev, "could not register ac97 pcm device\n");
808 		goto err_ac97_bus;
809 	}
810 
811 	retval = snd_card_register(card);
812 	if (retval) {
813 		dev_dbg(&pdev->dev, "could not register sound card\n");
814 		goto err_ac97_bus;
815 	}
816 
817 	platform_set_drvdata(pdev, card);
818 
819 	dev_info(&pdev->dev, "Atmel AC97 controller at 0x%p, irq = %d\n",
820 			chip->regs, irq);
821 
822 	return 0;
823 
824 err_ac97_bus:
825 	iounmap(chip->regs);
826 err_ioremap:
827 	free_irq(irq, chip);
828 err_request_irq:
829 	snd_card_free(card);
830 err_snd_card_new:
831 	clk_disable_unprepare(pclk);
832 err_prepare_enable:
833 	clk_put(pclk);
834 	return retval;
835 }
836 
837 #ifdef CONFIG_PM_SLEEP
838 static int atmel_ac97c_suspend(struct device *pdev)
839 {
840 	struct snd_card *card = dev_get_drvdata(pdev);
841 	struct atmel_ac97c *chip = card->private_data;
842 
843 	clk_disable_unprepare(chip->pclk);
844 	return 0;
845 }
846 
847 static int atmel_ac97c_resume(struct device *pdev)
848 {
849 	struct snd_card *card = dev_get_drvdata(pdev);
850 	struct atmel_ac97c *chip = card->private_data;
851 	int ret = clk_prepare_enable(chip->pclk);
852 
853 	return ret;
854 }
855 
856 static SIMPLE_DEV_PM_OPS(atmel_ac97c_pm, atmel_ac97c_suspend, atmel_ac97c_resume);
857 #define ATMEL_AC97C_PM_OPS	&atmel_ac97c_pm
858 #else
859 #define ATMEL_AC97C_PM_OPS	NULL
860 #endif
861 
862 static int atmel_ac97c_remove(struct platform_device *pdev)
863 {
864 	struct snd_card *card = platform_get_drvdata(pdev);
865 	struct atmel_ac97c *chip = get_chip(card);
866 
867 	ac97c_writel(chip, CAMR, 0);
868 	ac97c_writel(chip, COMR, 0);
869 	ac97c_writel(chip, MR,   0);
870 
871 	clk_disable_unprepare(chip->pclk);
872 	clk_put(chip->pclk);
873 	iounmap(chip->regs);
874 	free_irq(chip->irq, chip);
875 
876 	snd_card_free(card);
877 
878 	return 0;
879 }
880 
881 static struct platform_driver atmel_ac97c_driver = {
882 	.probe		= atmel_ac97c_probe,
883 	.remove		= atmel_ac97c_remove,
884 	.driver		= {
885 		.name	= "atmel_ac97c",
886 		.pm	= ATMEL_AC97C_PM_OPS,
887 		.of_match_table = atmel_ac97c_dt_ids,
888 	},
889 };
890 module_platform_driver(atmel_ac97c_driver);
891 
892 MODULE_LICENSE("GPL");
893 MODULE_DESCRIPTION("Driver for Atmel AC97 controller");
894 MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
895