xref: /linux/sound/atmel/ac97c.c (revision 2697b79a469b68e3ad3640f55284359c1396278d)
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/mod_devicetable.h>
16 #include <linux/module.h>
17 #include <linux/platform_device.h>
18 #include <linux/mutex.h>
19 #include <linux/types.h>
20 #include <linux/io.h>
21 
22 #include <sound/core.h>
23 #include <sound/initval.h>
24 #include <sound/pcm.h>
25 #include <sound/pcm_params.h>
26 #include <sound/ac97_codec.h>
27 #include <sound/memalloc.h>
28 
29 #include "ac97c.h"
30 
31 /* Serialize access to opened variable */
32 static DEFINE_MUTEX(opened_mutex);
33 
34 struct atmel_ac97c {
35 	struct clk			*pclk;
36 	struct platform_device		*pdev;
37 
38 	struct snd_pcm_substream	*playback_substream;
39 	struct snd_pcm_substream	*capture_substream;
40 	struct snd_card			*card;
41 	struct snd_pcm			*pcm;
42 	struct snd_ac97			*ac97;
43 	struct snd_ac97_bus		*ac97_bus;
44 
45 	u64				cur_format;
46 	unsigned int			cur_rate;
47 	int				playback_period, capture_period;
48 	/* Serialize access to opened variable */
49 	spinlock_t			lock;
50 	void __iomem			*regs;
51 	int				irq;
52 	int				opened;
53 	struct gpio_desc		*reset_pin;
54 };
55 
56 #define get_chip(card) ((struct atmel_ac97c *)(card)->private_data)
57 
58 #define ac97c_writel(chip, reg, val)			\
59 	__raw_writel((val), (chip)->regs + AC97C_##reg)
60 #define ac97c_readl(chip, reg)				\
61 	__raw_readl((chip)->regs + AC97C_##reg)
62 
63 static const struct snd_pcm_hardware atmel_ac97c_hw = {
64 	.info			= (SNDRV_PCM_INFO_MMAP
65 				  | SNDRV_PCM_INFO_MMAP_VALID
66 				  | SNDRV_PCM_INFO_INTERLEAVED
67 				  | SNDRV_PCM_INFO_BLOCK_TRANSFER
68 				  | SNDRV_PCM_INFO_JOINT_DUPLEX
69 				  | SNDRV_PCM_INFO_RESUME
70 				  | SNDRV_PCM_INFO_PAUSE),
71 	.formats		= (SNDRV_PCM_FMTBIT_S16_BE
72 				  | SNDRV_PCM_FMTBIT_S16_LE),
73 	.rates			= (SNDRV_PCM_RATE_CONTINUOUS),
74 	.rate_min		= 4000,
75 	.rate_max		= 48000,
76 	.channels_min		= 1,
77 	.channels_max		= 2,
78 	.buffer_bytes_max	= 2 * 2 * 64 * 2048,
79 	.period_bytes_min	= 4096,
80 	.period_bytes_max	= 4096,
81 	.periods_min		= 6,
82 	.periods_max		= 64,
83 };
84 
85 static int atmel_ac97c_playback_open(struct snd_pcm_substream *substream)
86 {
87 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
88 	struct snd_pcm_runtime *runtime = substream->runtime;
89 
90 	mutex_lock(&opened_mutex);
91 	chip->opened++;
92 	runtime->hw = atmel_ac97c_hw;
93 	if (chip->cur_rate) {
94 		runtime->hw.rate_min = chip->cur_rate;
95 		runtime->hw.rate_max = chip->cur_rate;
96 	}
97 	if (chip->cur_format)
98 		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
99 	mutex_unlock(&opened_mutex);
100 	chip->playback_substream = substream;
101 	return 0;
102 }
103 
104 static int atmel_ac97c_capture_open(struct snd_pcm_substream *substream)
105 {
106 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
107 	struct snd_pcm_runtime *runtime = substream->runtime;
108 
109 	mutex_lock(&opened_mutex);
110 	chip->opened++;
111 	runtime->hw = atmel_ac97c_hw;
112 	if (chip->cur_rate) {
113 		runtime->hw.rate_min = chip->cur_rate;
114 		runtime->hw.rate_max = chip->cur_rate;
115 	}
116 	if (chip->cur_format)
117 		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
118 	mutex_unlock(&opened_mutex);
119 	chip->capture_substream = substream;
120 	return 0;
121 }
122 
123 static int atmel_ac97c_playback_close(struct snd_pcm_substream *substream)
124 {
125 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
126 
127 	mutex_lock(&opened_mutex);
128 	chip->opened--;
129 	if (!chip->opened) {
130 		chip->cur_rate = 0;
131 		chip->cur_format = 0;
132 	}
133 	mutex_unlock(&opened_mutex);
134 
135 	chip->playback_substream = NULL;
136 
137 	return 0;
138 }
139 
140 static int atmel_ac97c_capture_close(struct snd_pcm_substream *substream)
141 {
142 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
143 
144 	mutex_lock(&opened_mutex);
145 	chip->opened--;
146 	if (!chip->opened) {
147 		chip->cur_rate = 0;
148 		chip->cur_format = 0;
149 	}
150 	mutex_unlock(&opened_mutex);
151 
152 	chip->capture_substream = NULL;
153 
154 	return 0;
155 }
156 
157 static int atmel_ac97c_playback_hw_params(struct snd_pcm_substream *substream,
158 		struct snd_pcm_hw_params *hw_params)
159 {
160 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
161 
162 	/* Set restrictions to params. */
163 	mutex_lock(&opened_mutex);
164 	chip->cur_rate = params_rate(hw_params);
165 	chip->cur_format = params_format(hw_params);
166 	mutex_unlock(&opened_mutex);
167 
168 	return 0;
169 }
170 
171 static int atmel_ac97c_capture_hw_params(struct snd_pcm_substream *substream,
172 		struct snd_pcm_hw_params *hw_params)
173 {
174 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
175 
176 	/* Set restrictions to params. */
177 	mutex_lock(&opened_mutex);
178 	chip->cur_rate = params_rate(hw_params);
179 	chip->cur_format = params_format(hw_params);
180 	mutex_unlock(&opened_mutex);
181 
182 	return 0;
183 }
184 
185 static int atmel_ac97c_playback_prepare(struct snd_pcm_substream *substream)
186 {
187 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
188 	struct snd_pcm_runtime *runtime = substream->runtime;
189 	int block_size = frames_to_bytes(runtime, runtime->period_size);
190 	unsigned long word = ac97c_readl(chip, OCA);
191 	int retval;
192 
193 	chip->playback_period = 0;
194 	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
195 
196 	/* assign channels to AC97C channel A */
197 	switch (runtime->channels) {
198 	case 1:
199 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
200 		break;
201 	case 2:
202 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
203 			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
204 		break;
205 	default:
206 		/* TODO: support more than two channels */
207 		return -EINVAL;
208 	}
209 	ac97c_writel(chip, OCA, word);
210 
211 	/* configure sample format and size */
212 	word = ac97c_readl(chip, CAMR);
213 	if (chip->opened <= 1)
214 		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
215 	else
216 		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
217 
218 	switch (runtime->format) {
219 	case SNDRV_PCM_FORMAT_S16_LE:
220 		break;
221 	case SNDRV_PCM_FORMAT_S16_BE:
222 		word &= ~(AC97C_CMR_CEM_LITTLE);
223 		break;
224 	default:
225 		word = ac97c_readl(chip, OCA);
226 		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
227 		ac97c_writel(chip, OCA, word);
228 		return -EINVAL;
229 	}
230 
231 	/* Enable underrun interrupt on channel A */
232 	word |= AC97C_CSR_UNRUN;
233 
234 	ac97c_writel(chip, CAMR, word);
235 
236 	/* Enable channel A event interrupt */
237 	word = ac97c_readl(chip, IMR);
238 	word |= AC97C_SR_CAEVT;
239 	ac97c_writel(chip, IER, word);
240 
241 	/* set variable rate if needed */
242 	if (runtime->rate != 48000) {
243 		word = ac97c_readl(chip, MR);
244 		word |= AC97C_MR_VRA;
245 		ac97c_writel(chip, MR, word);
246 	} else {
247 		word = ac97c_readl(chip, MR);
248 		word &= ~(AC97C_MR_VRA);
249 		ac97c_writel(chip, MR, word);
250 	}
251 
252 	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_FRONT_DAC_RATE,
253 			runtime->rate);
254 	if (retval)
255 		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
256 				runtime->rate);
257 
258 	/* Initialize and start the PDC */
259 	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_TPR);
260 	writel(block_size / 2, chip->regs + ATMEL_PDC_TCR);
261 	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_TNPR);
262 	writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
263 
264 	return retval;
265 }
266 
267 static int atmel_ac97c_capture_prepare(struct snd_pcm_substream *substream)
268 {
269 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
270 	struct snd_pcm_runtime *runtime = substream->runtime;
271 	int block_size = frames_to_bytes(runtime, runtime->period_size);
272 	unsigned long word = ac97c_readl(chip, ICA);
273 	int retval;
274 
275 	chip->capture_period = 0;
276 	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
277 
278 	/* assign channels to AC97C channel A */
279 	switch (runtime->channels) {
280 	case 1:
281 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
282 		break;
283 	case 2:
284 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
285 			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
286 		break;
287 	default:
288 		/* TODO: support more than two channels */
289 		return -EINVAL;
290 	}
291 	ac97c_writel(chip, ICA, word);
292 
293 	/* configure sample format and size */
294 	word = ac97c_readl(chip, CAMR);
295 	if (chip->opened <= 1)
296 		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
297 	else
298 		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
299 
300 	switch (runtime->format) {
301 	case SNDRV_PCM_FORMAT_S16_LE:
302 		break;
303 	case SNDRV_PCM_FORMAT_S16_BE:
304 		word &= ~(AC97C_CMR_CEM_LITTLE);
305 		break;
306 	default:
307 		word = ac97c_readl(chip, ICA);
308 		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
309 		ac97c_writel(chip, ICA, word);
310 		return -EINVAL;
311 	}
312 
313 	/* Enable overrun interrupt on channel A */
314 	word |= AC97C_CSR_OVRUN;
315 
316 	ac97c_writel(chip, CAMR, word);
317 
318 	/* Enable channel A event interrupt */
319 	word = ac97c_readl(chip, IMR);
320 	word |= AC97C_SR_CAEVT;
321 	ac97c_writel(chip, IER, word);
322 
323 	/* set variable rate if needed */
324 	if (runtime->rate != 48000) {
325 		word = ac97c_readl(chip, MR);
326 		word |= AC97C_MR_VRA;
327 		ac97c_writel(chip, MR, word);
328 	} else {
329 		word = ac97c_readl(chip, MR);
330 		word &= ~(AC97C_MR_VRA);
331 		ac97c_writel(chip, MR, word);
332 	}
333 
334 	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_LR_ADC_RATE,
335 			runtime->rate);
336 	if (retval)
337 		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
338 				runtime->rate);
339 
340 	/* Initialize and start the PDC */
341 	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_RPR);
342 	writel(block_size / 2, chip->regs + ATMEL_PDC_RCR);
343 	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_RNPR);
344 	writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
345 
346 	return retval;
347 }
348 
349 static int
350 atmel_ac97c_playback_trigger(struct snd_pcm_substream *substream, int cmd)
351 {
352 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
353 	unsigned long camr, ptcr = 0;
354 
355 	camr = ac97c_readl(chip, CAMR);
356 
357 	switch (cmd) {
358 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
359 	case SNDRV_PCM_TRIGGER_RESUME:
360 	case SNDRV_PCM_TRIGGER_START:
361 		ptcr = ATMEL_PDC_TXTEN;
362 		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDTX;
363 		break;
364 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
365 	case SNDRV_PCM_TRIGGER_SUSPEND:
366 	case SNDRV_PCM_TRIGGER_STOP:
367 		ptcr |= ATMEL_PDC_TXTDIS;
368 		if (chip->opened <= 1)
369 			camr &= ~AC97C_CMR_CENA;
370 		break;
371 	default:
372 		return -EINVAL;
373 	}
374 
375 	ac97c_writel(chip, CAMR, camr);
376 	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
377 	return 0;
378 }
379 
380 static int
381 atmel_ac97c_capture_trigger(struct snd_pcm_substream *substream, int cmd)
382 {
383 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
384 	unsigned long camr, ptcr = 0;
385 
386 	camr = ac97c_readl(chip, CAMR);
387 	ptcr = readl(chip->regs + ATMEL_PDC_PTSR);
388 
389 	switch (cmd) {
390 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
391 	case SNDRV_PCM_TRIGGER_RESUME:
392 	case SNDRV_PCM_TRIGGER_START:
393 		ptcr = ATMEL_PDC_RXTEN;
394 		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDRX;
395 		break;
396 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
397 	case SNDRV_PCM_TRIGGER_SUSPEND:
398 	case SNDRV_PCM_TRIGGER_STOP:
399 		ptcr |= ATMEL_PDC_RXTDIS;
400 		if (chip->opened <= 1)
401 			camr &= ~AC97C_CMR_CENA;
402 		break;
403 	default:
404 		return -EINVAL;
405 	}
406 
407 	ac97c_writel(chip, CAMR, camr);
408 	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
409 	return 0;
410 }
411 
412 static snd_pcm_uframes_t
413 atmel_ac97c_playback_pointer(struct snd_pcm_substream *substream)
414 {
415 	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
416 	struct snd_pcm_runtime	*runtime = substream->runtime;
417 	snd_pcm_uframes_t	frames;
418 	unsigned long		bytes;
419 
420 	bytes = readl(chip->regs + ATMEL_PDC_TPR);
421 	bytes -= runtime->dma_addr;
422 
423 	frames = bytes_to_frames(runtime, bytes);
424 	if (frames >= runtime->buffer_size)
425 		frames -= runtime->buffer_size;
426 	return frames;
427 }
428 
429 static snd_pcm_uframes_t
430 atmel_ac97c_capture_pointer(struct snd_pcm_substream *substream)
431 {
432 	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
433 	struct snd_pcm_runtime	*runtime = substream->runtime;
434 	snd_pcm_uframes_t	frames;
435 	unsigned long		bytes;
436 
437 	bytes = readl(chip->regs + ATMEL_PDC_RPR);
438 	bytes -= runtime->dma_addr;
439 
440 	frames = bytes_to_frames(runtime, bytes);
441 	if (frames >= runtime->buffer_size)
442 		frames -= runtime->buffer_size;
443 	return frames;
444 }
445 
446 static const struct snd_pcm_ops atmel_ac97_playback_ops = {
447 	.open		= atmel_ac97c_playback_open,
448 	.close		= atmel_ac97c_playback_close,
449 	.hw_params	= atmel_ac97c_playback_hw_params,
450 	.prepare	= atmel_ac97c_playback_prepare,
451 	.trigger	= atmel_ac97c_playback_trigger,
452 	.pointer	= atmel_ac97c_playback_pointer,
453 };
454 
455 static const struct snd_pcm_ops atmel_ac97_capture_ops = {
456 	.open		= atmel_ac97c_capture_open,
457 	.close		= atmel_ac97c_capture_close,
458 	.hw_params	= atmel_ac97c_capture_hw_params,
459 	.prepare	= atmel_ac97c_capture_prepare,
460 	.trigger	= atmel_ac97c_capture_trigger,
461 	.pointer	= atmel_ac97c_capture_pointer,
462 };
463 
464 static irqreturn_t atmel_ac97c_interrupt(int irq, void *dev)
465 {
466 	struct atmel_ac97c	*chip  = (struct atmel_ac97c *)dev;
467 	irqreturn_t		retval = IRQ_NONE;
468 	u32			sr     = ac97c_readl(chip, SR);
469 	u32			casr   = ac97c_readl(chip, CASR);
470 	u32			cosr   = ac97c_readl(chip, COSR);
471 	u32			camr   = ac97c_readl(chip, CAMR);
472 
473 	if (sr & AC97C_SR_CAEVT) {
474 		struct snd_pcm_runtime *runtime;
475 		int offset, next_period, block_size;
476 		dev_dbg(&chip->pdev->dev, "channel A event%s%s%s%s%s%s\n",
477 			(casr & AC97C_CSR_OVRUN)   ? " OVRUN"   : "",
478 			(casr & AC97C_CSR_RXRDY)   ? " RXRDY"   : "",
479 			(casr & AC97C_CSR_UNRUN)   ? " UNRUN"   : "",
480 			(casr & AC97C_CSR_TXEMPTY) ? " TXEMPTY" : "",
481 			(casr & AC97C_CSR_TXRDY)   ? " TXRDY"   : "",
482 			!casr                      ? " NONE"    : "");
483 		if ((casr & camr) & AC97C_CSR_ENDTX) {
484 			runtime = chip->playback_substream->runtime;
485 			block_size = frames_to_bytes(runtime, runtime->period_size);
486 			chip->playback_period++;
487 
488 			if (chip->playback_period == runtime->periods)
489 				chip->playback_period = 0;
490 			next_period = chip->playback_period + 1;
491 			if (next_period == runtime->periods)
492 				next_period = 0;
493 
494 			offset = block_size * next_period;
495 
496 			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_TNPR);
497 			writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
498 
499 			snd_pcm_period_elapsed(chip->playback_substream);
500 		}
501 		if ((casr & camr) & AC97C_CSR_ENDRX) {
502 			runtime = chip->capture_substream->runtime;
503 			block_size = frames_to_bytes(runtime, runtime->period_size);
504 			chip->capture_period++;
505 
506 			if (chip->capture_period == runtime->periods)
507 				chip->capture_period = 0;
508 			next_period = chip->capture_period + 1;
509 			if (next_period == runtime->periods)
510 				next_period = 0;
511 
512 			offset = block_size * next_period;
513 
514 			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_RNPR);
515 			writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
516 			snd_pcm_period_elapsed(chip->capture_substream);
517 		}
518 		retval = IRQ_HANDLED;
519 	}
520 
521 	if (sr & AC97C_SR_COEVT) {
522 		dev_info(&chip->pdev->dev, "codec channel event%s%s%s%s%s\n",
523 			 (cosr & AC97C_CSR_OVRUN)   ? " OVRUN"   : "",
524 			 (cosr & AC97C_CSR_RXRDY)   ? " RXRDY"   : "",
525 			 (cosr & AC97C_CSR_TXEMPTY) ? " TXEMPTY" : "",
526 			 (cosr & AC97C_CSR_TXRDY)   ? " TXRDY"   : "",
527 			 !cosr                      ? " NONE"    : "");
528 		retval = IRQ_HANDLED;
529 	}
530 
531 	if (retval == IRQ_NONE) {
532 		dev_err(&chip->pdev->dev, "spurious interrupt sr 0x%08x "
533 				"casr 0x%08x cosr 0x%08x\n", sr, casr, cosr);
534 	}
535 
536 	return retval;
537 }
538 
539 static const struct ac97_pcm at91_ac97_pcm_defs[] = {
540 	/* Playback */
541 	{
542 		.exclusive = 1,
543 		.r = { {
544 			.slots = ((1 << AC97_SLOT_PCM_LEFT)
545 				  | (1 << AC97_SLOT_PCM_RIGHT)),
546 		} },
547 	},
548 	/* PCM in */
549 	{
550 		.stream = 1,
551 		.exclusive = 1,
552 		.r = { {
553 			.slots = ((1 << AC97_SLOT_PCM_LEFT)
554 					| (1 << AC97_SLOT_PCM_RIGHT)),
555 		} }
556 	},
557 	/* Mic in */
558 	{
559 		.stream = 1,
560 		.exclusive = 1,
561 		.r = { {
562 			.slots = (1<<AC97_SLOT_MIC),
563 		} }
564 	},
565 };
566 
567 static int atmel_ac97c_pcm_new(struct atmel_ac97c *chip)
568 {
569 	struct snd_pcm		*pcm;
570 	struct snd_pcm_hardware	hw = atmel_ac97c_hw;
571 	int			retval;
572 
573 	retval = snd_ac97_pcm_assign(chip->ac97_bus,
574 				     ARRAY_SIZE(at91_ac97_pcm_defs),
575 				     at91_ac97_pcm_defs);
576 	if (retval)
577 		return retval;
578 
579 	retval = snd_pcm_new(chip->card, chip->card->shortname, 0, 1, 1, &pcm);
580 	if (retval)
581 		return retval;
582 
583 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &atmel_ac97_capture_ops);
584 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &atmel_ac97_playback_ops);
585 
586 	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
587 			&chip->pdev->dev, hw.periods_min * hw.period_bytes_min,
588 			hw.buffer_bytes_max);
589 
590 	pcm->private_data = chip;
591 	pcm->info_flags = 0;
592 	strcpy(pcm->name, chip->card->shortname);
593 	chip->pcm = pcm;
594 
595 	return 0;
596 }
597 
598 static int atmel_ac97c_mixer_new(struct atmel_ac97c *chip)
599 {
600 	struct snd_ac97_template template;
601 	memset(&template, 0, sizeof(template));
602 	template.private_data = chip;
603 	return snd_ac97_mixer(chip->ac97_bus, &template, &chip->ac97);
604 }
605 
606 static void atmel_ac97c_write(struct snd_ac97 *ac97, unsigned short reg,
607 		unsigned short val)
608 {
609 	struct atmel_ac97c *chip = get_chip(ac97);
610 	unsigned long word;
611 	int timeout = 40;
612 
613 	word = (reg & 0x7f) << 16 | val;
614 
615 	do {
616 		if (ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) {
617 			ac97c_writel(chip, COTHR, word);
618 			return;
619 		}
620 		udelay(1);
621 	} while (--timeout);
622 
623 	dev_dbg(&chip->pdev->dev, "codec write timeout\n");
624 }
625 
626 static unsigned short atmel_ac97c_read(struct snd_ac97 *ac97,
627 		unsigned short reg)
628 {
629 	struct atmel_ac97c *chip = get_chip(ac97);
630 	unsigned long word;
631 	int timeout = 40;
632 	int write = 10;
633 
634 	word = (0x80 | (reg & 0x7f)) << 16;
635 
636 	if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0)
637 		ac97c_readl(chip, CORHR);
638 
639 retry_write:
640 	timeout = 40;
641 
642 	do {
643 		if ((ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) != 0) {
644 			ac97c_writel(chip, COTHR, word);
645 			goto read_reg;
646 		}
647 		udelay(10);
648 	} while (--timeout);
649 
650 	if (!--write)
651 		goto timed_out;
652 	goto retry_write;
653 
654 read_reg:
655 	do {
656 		if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0) {
657 			unsigned short val = ac97c_readl(chip, CORHR);
658 			return val;
659 		}
660 		udelay(10);
661 	} while (--timeout);
662 
663 	if (!--write)
664 		goto timed_out;
665 	goto retry_write;
666 
667 timed_out:
668 	dev_dbg(&chip->pdev->dev, "codec read timeout\n");
669 	return 0xffff;
670 }
671 
672 static void atmel_ac97c_reset(struct atmel_ac97c *chip)
673 {
674 	ac97c_writel(chip, MR,   0);
675 	ac97c_writel(chip, MR,   AC97C_MR_ENA);
676 	ac97c_writel(chip, CAMR, 0);
677 	ac97c_writel(chip, COMR, 0);
678 
679 	if (!IS_ERR(chip->reset_pin)) {
680 		gpiod_set_value(chip->reset_pin, 0);
681 		/* AC97 v2.2 specifications says minimum 1 us. */
682 		udelay(2);
683 		gpiod_set_value(chip->reset_pin, 1);
684 	} else {
685 		ac97c_writel(chip, MR, AC97C_MR_WRST | AC97C_MR_ENA);
686 		udelay(2);
687 		ac97c_writel(chip, MR, AC97C_MR_ENA);
688 	}
689 }
690 
691 static const struct of_device_id atmel_ac97c_dt_ids[] = {
692 	{ .compatible = "atmel,at91sam9263-ac97c", },
693 	{ }
694 };
695 MODULE_DEVICE_TABLE(of, atmel_ac97c_dt_ids);
696 
697 static int atmel_ac97c_probe(struct platform_device *pdev)
698 {
699 	struct device			*dev = &pdev->dev;
700 	struct snd_card			*card;
701 	struct atmel_ac97c		*chip;
702 	struct resource			*regs;
703 	struct clk			*pclk;
704 	static const struct snd_ac97_bus_ops	ops = {
705 		.write	= atmel_ac97c_write,
706 		.read	= atmel_ac97c_read,
707 	};
708 	int				retval;
709 	int				irq;
710 
711 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
712 	if (!regs) {
713 		dev_dbg(&pdev->dev, "no memory resource\n");
714 		return -ENXIO;
715 	}
716 
717 	irq = platform_get_irq(pdev, 0);
718 	if (irq < 0) {
719 		dev_dbg(&pdev->dev, "could not get irq: %d\n", irq);
720 		return irq;
721 	}
722 
723 	pclk = clk_get(&pdev->dev, "ac97_clk");
724 	if (IS_ERR(pclk)) {
725 		dev_dbg(&pdev->dev, "no peripheral clock\n");
726 		return PTR_ERR(pclk);
727 	}
728 	retval = clk_prepare_enable(pclk);
729 	if (retval)
730 		goto err_prepare_enable;
731 
732 	retval = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1,
733 			      SNDRV_DEFAULT_STR1, THIS_MODULE,
734 			      sizeof(struct atmel_ac97c), &card);
735 	if (retval) {
736 		dev_dbg(&pdev->dev, "could not create sound card device\n");
737 		goto err_snd_card_new;
738 	}
739 
740 	chip = get_chip(card);
741 
742 	retval = request_irq(irq, atmel_ac97c_interrupt, 0, "AC97C", chip);
743 	if (retval) {
744 		dev_dbg(&pdev->dev, "unable to request irq %d\n", irq);
745 		goto err_request_irq;
746 	}
747 	chip->irq = irq;
748 
749 	spin_lock_init(&chip->lock);
750 
751 	strcpy(card->driver, "Atmel AC97C");
752 	strcpy(card->shortname, "Atmel AC97C");
753 	sprintf(card->longname, "Atmel AC97 controller");
754 
755 	chip->card = card;
756 	chip->pclk = pclk;
757 	chip->pdev = pdev;
758 	chip->regs = ioremap(regs->start, resource_size(regs));
759 
760 	if (!chip->regs) {
761 		dev_dbg(&pdev->dev, "could not remap register memory\n");
762 		retval = -ENOMEM;
763 		goto err_ioremap;
764 	}
765 
766 	chip->reset_pin = devm_gpiod_get_index(dev, "ac97", 2, GPIOD_OUT_HIGH);
767 	if (IS_ERR(chip->reset_pin))
768 		dev_dbg(dev, "reset pin not available\n");
769 
770 	atmel_ac97c_reset(chip);
771 
772 	/* Enable overrun interrupt from codec channel */
773 	ac97c_writel(chip, COMR, AC97C_CSR_OVRUN);
774 	ac97c_writel(chip, IER, ac97c_readl(chip, IMR) | AC97C_SR_COEVT);
775 
776 	retval = snd_ac97_bus(card, 0, &ops, chip, &chip->ac97_bus);
777 	if (retval) {
778 		dev_dbg(&pdev->dev, "could not register on ac97 bus\n");
779 		goto err_ac97_bus;
780 	}
781 
782 	retval = atmel_ac97c_mixer_new(chip);
783 	if (retval) {
784 		dev_dbg(&pdev->dev, "could not register ac97 mixer\n");
785 		goto err_ac97_bus;
786 	}
787 
788 	retval = atmel_ac97c_pcm_new(chip);
789 	if (retval) {
790 		dev_dbg(&pdev->dev, "could not register ac97 pcm device\n");
791 		goto err_ac97_bus;
792 	}
793 
794 	retval = snd_card_register(card);
795 	if (retval) {
796 		dev_dbg(&pdev->dev, "could not register sound card\n");
797 		goto err_ac97_bus;
798 	}
799 
800 	platform_set_drvdata(pdev, card);
801 
802 	dev_info(&pdev->dev, "Atmel AC97 controller at 0x%p, irq = %d\n",
803 			chip->regs, irq);
804 
805 	return 0;
806 
807 err_ac97_bus:
808 	iounmap(chip->regs);
809 err_ioremap:
810 	free_irq(irq, chip);
811 err_request_irq:
812 	snd_card_free(card);
813 err_snd_card_new:
814 	clk_disable_unprepare(pclk);
815 err_prepare_enable:
816 	clk_put(pclk);
817 	return retval;
818 }
819 
820 #ifdef CONFIG_PM_SLEEP
821 static int atmel_ac97c_suspend(struct device *pdev)
822 {
823 	struct snd_card *card = dev_get_drvdata(pdev);
824 	struct atmel_ac97c *chip = card->private_data;
825 
826 	clk_disable_unprepare(chip->pclk);
827 	return 0;
828 }
829 
830 static int atmel_ac97c_resume(struct device *pdev)
831 {
832 	struct snd_card *card = dev_get_drvdata(pdev);
833 	struct atmel_ac97c *chip = card->private_data;
834 	int ret = clk_prepare_enable(chip->pclk);
835 
836 	return ret;
837 }
838 
839 static SIMPLE_DEV_PM_OPS(atmel_ac97c_pm, atmel_ac97c_suspend, atmel_ac97c_resume);
840 #define ATMEL_AC97C_PM_OPS	&atmel_ac97c_pm
841 #else
842 #define ATMEL_AC97C_PM_OPS	NULL
843 #endif
844 
845 static void atmel_ac97c_remove(struct platform_device *pdev)
846 {
847 	struct snd_card *card = platform_get_drvdata(pdev);
848 	struct atmel_ac97c *chip = get_chip(card);
849 
850 	ac97c_writel(chip, CAMR, 0);
851 	ac97c_writel(chip, COMR, 0);
852 	ac97c_writel(chip, MR,   0);
853 
854 	clk_disable_unprepare(chip->pclk);
855 	clk_put(chip->pclk);
856 	iounmap(chip->regs);
857 	free_irq(chip->irq, chip);
858 
859 	snd_card_free(card);
860 }
861 
862 static struct platform_driver atmel_ac97c_driver = {
863 	.probe		= atmel_ac97c_probe,
864 	.remove_new	= atmel_ac97c_remove,
865 	.driver		= {
866 		.name	= "atmel_ac97c",
867 		.pm	= ATMEL_AC97C_PM_OPS,
868 		.of_match_table = atmel_ac97c_dt_ids,
869 	},
870 };
871 module_platform_driver(atmel_ac97c_driver);
872 
873 MODULE_LICENSE("GPL");
874 MODULE_DESCRIPTION("Driver for Atmel AC97 controller");
875 MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
876