xref: /linux/sound/atmel/ac97c.c (revision a2cce7a9f1b8cc3d4edce106fb971529f1d4d9ce)
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/dmaengine.h>
15 #include <linux/dma-mapping.h>
16 #include <linux/atmel_pdc.h>
17 #include <linux/init.h>
18 #include <linux/interrupt.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/mutex.h>
22 #include <linux/gpio.h>
23 #include <linux/types.h>
24 #include <linux/io.h>
25 #include <linux/of.h>
26 #include <linux/of_gpio.h>
27 #include <linux/of_device.h>
28 
29 #include <sound/core.h>
30 #include <sound/initval.h>
31 #include <sound/pcm.h>
32 #include <sound/pcm_params.h>
33 #include <sound/ac97_codec.h>
34 #include <sound/atmel-ac97c.h>
35 #include <sound/memalloc.h>
36 
37 #include <linux/platform_data/dma-dw.h>
38 #include <linux/dma/dw.h>
39 
40 #ifdef CONFIG_AVR32
41 #include <mach/cpu.h>
42 #else
43 #define cpu_is_at32ap7000() 0
44 #endif
45 
46 #include "ac97c.h"
47 
48 enum {
49 	DMA_TX_READY = 0,
50 	DMA_RX_READY,
51 	DMA_TX_CHAN_PRESENT,
52 	DMA_RX_CHAN_PRESENT,
53 };
54 
55 /* Serialize access to opened variable */
56 static DEFINE_MUTEX(opened_mutex);
57 
58 struct atmel_ac97c_dma {
59 	struct dma_chan			*rx_chan;
60 	struct dma_chan			*tx_chan;
61 };
62 
63 struct atmel_ac97c {
64 	struct clk			*pclk;
65 	struct platform_device		*pdev;
66 	struct atmel_ac97c_dma		dma;
67 
68 	struct snd_pcm_substream	*playback_substream;
69 	struct snd_pcm_substream	*capture_substream;
70 	struct snd_card			*card;
71 	struct snd_pcm			*pcm;
72 	struct snd_ac97			*ac97;
73 	struct snd_ac97_bus		*ac97_bus;
74 
75 	u64				cur_format;
76 	unsigned int			cur_rate;
77 	unsigned long			flags;
78 	int				playback_period, capture_period;
79 	/* Serialize access to opened variable */
80 	spinlock_t			lock;
81 	void __iomem			*regs;
82 	int				irq;
83 	int				opened;
84 	int				reset_pin;
85 };
86 
87 #define get_chip(card) ((struct atmel_ac97c *)(card)->private_data)
88 
89 #define ac97c_writel(chip, reg, val)			\
90 	__raw_writel((val), (chip)->regs + AC97C_##reg)
91 #define ac97c_readl(chip, reg)				\
92 	__raw_readl((chip)->regs + AC97C_##reg)
93 
94 /* This function is called by the DMA driver. */
95 static void atmel_ac97c_dma_playback_period_done(void *arg)
96 {
97 	struct atmel_ac97c *chip = arg;
98 	snd_pcm_period_elapsed(chip->playback_substream);
99 }
100 
101 static void atmel_ac97c_dma_capture_period_done(void *arg)
102 {
103 	struct atmel_ac97c *chip = arg;
104 	snd_pcm_period_elapsed(chip->capture_substream);
105 }
106 
107 static int atmel_ac97c_prepare_dma(struct atmel_ac97c *chip,
108 		struct snd_pcm_substream *substream,
109 		enum dma_transfer_direction direction)
110 {
111 	struct dma_chan			*chan;
112 	struct dw_cyclic_desc		*cdesc;
113 	struct snd_pcm_runtime		*runtime = substream->runtime;
114 	unsigned long			buffer_len, period_len;
115 
116 	/*
117 	 * We don't do DMA on "complex" transfers, i.e. with
118 	 * non-halfword-aligned buffers or lengths.
119 	 */
120 	if (runtime->dma_addr & 1 || runtime->buffer_size & 1) {
121 		dev_dbg(&chip->pdev->dev, "too complex transfer\n");
122 		return -EINVAL;
123 	}
124 
125 	if (direction == DMA_MEM_TO_DEV)
126 		chan = chip->dma.tx_chan;
127 	else
128 		chan = chip->dma.rx_chan;
129 
130 	buffer_len = frames_to_bytes(runtime, runtime->buffer_size);
131 	period_len = frames_to_bytes(runtime, runtime->period_size);
132 
133 	cdesc = dw_dma_cyclic_prep(chan, runtime->dma_addr, buffer_len,
134 			period_len, direction);
135 	if (IS_ERR(cdesc)) {
136 		dev_dbg(&chip->pdev->dev, "could not prepare cyclic DMA\n");
137 		return PTR_ERR(cdesc);
138 	}
139 
140 	if (direction == DMA_MEM_TO_DEV) {
141 		cdesc->period_callback = atmel_ac97c_dma_playback_period_done;
142 		set_bit(DMA_TX_READY, &chip->flags);
143 	} else {
144 		cdesc->period_callback = atmel_ac97c_dma_capture_period_done;
145 		set_bit(DMA_RX_READY, &chip->flags);
146 	}
147 
148 	cdesc->period_callback_param = chip;
149 
150 	return 0;
151 }
152 
153 static struct snd_pcm_hardware atmel_ac97c_hw = {
154 	.info			= (SNDRV_PCM_INFO_MMAP
155 				  | SNDRV_PCM_INFO_MMAP_VALID
156 				  | SNDRV_PCM_INFO_INTERLEAVED
157 				  | SNDRV_PCM_INFO_BLOCK_TRANSFER
158 				  | SNDRV_PCM_INFO_JOINT_DUPLEX
159 				  | SNDRV_PCM_INFO_RESUME
160 				  | SNDRV_PCM_INFO_PAUSE),
161 	.formats		= (SNDRV_PCM_FMTBIT_S16_BE
162 				  | SNDRV_PCM_FMTBIT_S16_LE),
163 	.rates			= (SNDRV_PCM_RATE_CONTINUOUS),
164 	.rate_min		= 4000,
165 	.rate_max		= 48000,
166 	.channels_min		= 1,
167 	.channels_max		= 2,
168 	.buffer_bytes_max	= 2 * 2 * 64 * 2048,
169 	.period_bytes_min	= 4096,
170 	.period_bytes_max	= 4096,
171 	.periods_min		= 6,
172 	.periods_max		= 64,
173 };
174 
175 static int atmel_ac97c_playback_open(struct snd_pcm_substream *substream)
176 {
177 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
178 	struct snd_pcm_runtime *runtime = substream->runtime;
179 
180 	mutex_lock(&opened_mutex);
181 	chip->opened++;
182 	runtime->hw = atmel_ac97c_hw;
183 	if (chip->cur_rate) {
184 		runtime->hw.rate_min = chip->cur_rate;
185 		runtime->hw.rate_max = chip->cur_rate;
186 	}
187 	if (chip->cur_format)
188 		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
189 	mutex_unlock(&opened_mutex);
190 	chip->playback_substream = substream;
191 	return 0;
192 }
193 
194 static int atmel_ac97c_capture_open(struct snd_pcm_substream *substream)
195 {
196 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
197 	struct snd_pcm_runtime *runtime = substream->runtime;
198 
199 	mutex_lock(&opened_mutex);
200 	chip->opened++;
201 	runtime->hw = atmel_ac97c_hw;
202 	if (chip->cur_rate) {
203 		runtime->hw.rate_min = chip->cur_rate;
204 		runtime->hw.rate_max = chip->cur_rate;
205 	}
206 	if (chip->cur_format)
207 		runtime->hw.formats = pcm_format_to_bits(chip->cur_format);
208 	mutex_unlock(&opened_mutex);
209 	chip->capture_substream = substream;
210 	return 0;
211 }
212 
213 static int atmel_ac97c_playback_close(struct snd_pcm_substream *substream)
214 {
215 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
216 
217 	mutex_lock(&opened_mutex);
218 	chip->opened--;
219 	if (!chip->opened) {
220 		chip->cur_rate = 0;
221 		chip->cur_format = 0;
222 	}
223 	mutex_unlock(&opened_mutex);
224 
225 	chip->playback_substream = NULL;
226 
227 	return 0;
228 }
229 
230 static int atmel_ac97c_capture_close(struct snd_pcm_substream *substream)
231 {
232 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
233 
234 	mutex_lock(&opened_mutex);
235 	chip->opened--;
236 	if (!chip->opened) {
237 		chip->cur_rate = 0;
238 		chip->cur_format = 0;
239 	}
240 	mutex_unlock(&opened_mutex);
241 
242 	chip->capture_substream = NULL;
243 
244 	return 0;
245 }
246 
247 static int atmel_ac97c_playback_hw_params(struct snd_pcm_substream *substream,
248 		struct snd_pcm_hw_params *hw_params)
249 {
250 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
251 	int retval;
252 
253 	retval = snd_pcm_lib_malloc_pages(substream,
254 					params_buffer_bytes(hw_params));
255 	if (retval < 0)
256 		return retval;
257 	/* snd_pcm_lib_malloc_pages returns 1 if buffer is changed. */
258 	if (cpu_is_at32ap7000()) {
259 		/* snd_pcm_lib_malloc_pages returns 1 if buffer is changed. */
260 		if (retval == 1)
261 			if (test_and_clear_bit(DMA_TX_READY, &chip->flags))
262 				dw_dma_cyclic_free(chip->dma.tx_chan);
263 	}
264 	/* Set restrictions to params. */
265 	mutex_lock(&opened_mutex);
266 	chip->cur_rate = params_rate(hw_params);
267 	chip->cur_format = params_format(hw_params);
268 	mutex_unlock(&opened_mutex);
269 
270 	return retval;
271 }
272 
273 static int atmel_ac97c_capture_hw_params(struct snd_pcm_substream *substream,
274 		struct snd_pcm_hw_params *hw_params)
275 {
276 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
277 	int retval;
278 
279 	retval = snd_pcm_lib_malloc_pages(substream,
280 					params_buffer_bytes(hw_params));
281 	if (retval < 0)
282 		return retval;
283 	/* snd_pcm_lib_malloc_pages returns 1 if buffer is changed. */
284 	if (cpu_is_at32ap7000() && retval == 1)
285 		if (test_and_clear_bit(DMA_RX_READY, &chip->flags))
286 			dw_dma_cyclic_free(chip->dma.rx_chan);
287 
288 	/* Set restrictions to params. */
289 	mutex_lock(&opened_mutex);
290 	chip->cur_rate = params_rate(hw_params);
291 	chip->cur_format = params_format(hw_params);
292 	mutex_unlock(&opened_mutex);
293 
294 	return retval;
295 }
296 
297 static int atmel_ac97c_playback_hw_free(struct snd_pcm_substream *substream)
298 {
299 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
300 	if (cpu_is_at32ap7000()) {
301 		if (test_and_clear_bit(DMA_TX_READY, &chip->flags))
302 			dw_dma_cyclic_free(chip->dma.tx_chan);
303 	}
304 	return snd_pcm_lib_free_pages(substream);
305 }
306 
307 static int atmel_ac97c_capture_hw_free(struct snd_pcm_substream *substream)
308 {
309 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
310 	if (cpu_is_at32ap7000()) {
311 		if (test_and_clear_bit(DMA_RX_READY, &chip->flags))
312 			dw_dma_cyclic_free(chip->dma.rx_chan);
313 	}
314 	return snd_pcm_lib_free_pages(substream);
315 }
316 
317 static int atmel_ac97c_playback_prepare(struct snd_pcm_substream *substream)
318 {
319 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
320 	struct snd_pcm_runtime *runtime = substream->runtime;
321 	int block_size = frames_to_bytes(runtime, runtime->period_size);
322 	unsigned long word = ac97c_readl(chip, OCA);
323 	int retval;
324 
325 	chip->playback_period = 0;
326 	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
327 
328 	/* assign channels to AC97C channel A */
329 	switch (runtime->channels) {
330 	case 1:
331 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
332 		break;
333 	case 2:
334 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
335 			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
336 		break;
337 	default:
338 		/* TODO: support more than two channels */
339 		return -EINVAL;
340 	}
341 	ac97c_writel(chip, OCA, word);
342 
343 	/* configure sample format and size */
344 	word = ac97c_readl(chip, CAMR);
345 	if (chip->opened <= 1)
346 		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
347 	else
348 		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
349 
350 	switch (runtime->format) {
351 	case SNDRV_PCM_FORMAT_S16_LE:
352 		if (cpu_is_at32ap7000())
353 			word |= AC97C_CMR_CEM_LITTLE;
354 		break;
355 	case SNDRV_PCM_FORMAT_S16_BE: /* fall through */
356 		word &= ~(AC97C_CMR_CEM_LITTLE);
357 		break;
358 	default:
359 		word = ac97c_readl(chip, OCA);
360 		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
361 		ac97c_writel(chip, OCA, word);
362 		return -EINVAL;
363 	}
364 
365 	/* Enable underrun interrupt on channel A */
366 	word |= AC97C_CSR_UNRUN;
367 
368 	ac97c_writel(chip, CAMR, word);
369 
370 	/* Enable channel A event interrupt */
371 	word = ac97c_readl(chip, IMR);
372 	word |= AC97C_SR_CAEVT;
373 	ac97c_writel(chip, IER, word);
374 
375 	/* set variable rate if needed */
376 	if (runtime->rate != 48000) {
377 		word = ac97c_readl(chip, MR);
378 		word |= AC97C_MR_VRA;
379 		ac97c_writel(chip, MR, word);
380 	} else {
381 		word = ac97c_readl(chip, MR);
382 		word &= ~(AC97C_MR_VRA);
383 		ac97c_writel(chip, MR, word);
384 	}
385 
386 	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_FRONT_DAC_RATE,
387 			runtime->rate);
388 	if (retval)
389 		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
390 				runtime->rate);
391 
392 	if (cpu_is_at32ap7000()) {
393 		if (!test_bit(DMA_TX_READY, &chip->flags))
394 			retval = atmel_ac97c_prepare_dma(chip, substream,
395 					DMA_MEM_TO_DEV);
396 	} else {
397 		/* Initialize and start the PDC */
398 		writel(runtime->dma_addr, chip->regs + ATMEL_PDC_TPR);
399 		writel(block_size / 2, chip->regs + ATMEL_PDC_TCR);
400 		writel(runtime->dma_addr + block_size,
401 				chip->regs + ATMEL_PDC_TNPR);
402 		writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
403 	}
404 
405 	return retval;
406 }
407 
408 static int atmel_ac97c_capture_prepare(struct snd_pcm_substream *substream)
409 {
410 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
411 	struct snd_pcm_runtime *runtime = substream->runtime;
412 	int block_size = frames_to_bytes(runtime, runtime->period_size);
413 	unsigned long word = ac97c_readl(chip, ICA);
414 	int retval;
415 
416 	chip->capture_period = 0;
417 	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
418 
419 	/* assign channels to AC97C channel A */
420 	switch (runtime->channels) {
421 	case 1:
422 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
423 		break;
424 	case 2:
425 		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
426 			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
427 		break;
428 	default:
429 		/* TODO: support more than two channels */
430 		return -EINVAL;
431 	}
432 	ac97c_writel(chip, ICA, word);
433 
434 	/* configure sample format and size */
435 	word = ac97c_readl(chip, CAMR);
436 	if (chip->opened <= 1)
437 		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
438 	else
439 		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
440 
441 	switch (runtime->format) {
442 	case SNDRV_PCM_FORMAT_S16_LE:
443 		if (cpu_is_at32ap7000())
444 			word |= AC97C_CMR_CEM_LITTLE;
445 		break;
446 	case SNDRV_PCM_FORMAT_S16_BE: /* fall through */
447 		word &= ~(AC97C_CMR_CEM_LITTLE);
448 		break;
449 	default:
450 		word = ac97c_readl(chip, ICA);
451 		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
452 		ac97c_writel(chip, ICA, word);
453 		return -EINVAL;
454 	}
455 
456 	/* Enable overrun interrupt on channel A */
457 	word |= AC97C_CSR_OVRUN;
458 
459 	ac97c_writel(chip, CAMR, word);
460 
461 	/* Enable channel A event interrupt */
462 	word = ac97c_readl(chip, IMR);
463 	word |= AC97C_SR_CAEVT;
464 	ac97c_writel(chip, IER, word);
465 
466 	/* set variable rate if needed */
467 	if (runtime->rate != 48000) {
468 		word = ac97c_readl(chip, MR);
469 		word |= AC97C_MR_VRA;
470 		ac97c_writel(chip, MR, word);
471 	} else {
472 		word = ac97c_readl(chip, MR);
473 		word &= ~(AC97C_MR_VRA);
474 		ac97c_writel(chip, MR, word);
475 	}
476 
477 	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_LR_ADC_RATE,
478 			runtime->rate);
479 	if (retval)
480 		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
481 				runtime->rate);
482 
483 	if (cpu_is_at32ap7000()) {
484 		if (!test_bit(DMA_RX_READY, &chip->flags))
485 			retval = atmel_ac97c_prepare_dma(chip, substream,
486 					DMA_DEV_TO_MEM);
487 	} else {
488 		/* Initialize and start the PDC */
489 		writel(runtime->dma_addr, chip->regs + ATMEL_PDC_RPR);
490 		writel(block_size / 2, chip->regs + ATMEL_PDC_RCR);
491 		writel(runtime->dma_addr + block_size,
492 				chip->regs + ATMEL_PDC_RNPR);
493 		writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
494 	}
495 
496 	return retval;
497 }
498 
499 static int
500 atmel_ac97c_playback_trigger(struct snd_pcm_substream *substream, int cmd)
501 {
502 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
503 	unsigned long camr, ptcr = 0;
504 	int retval = 0;
505 
506 	camr = ac97c_readl(chip, CAMR);
507 
508 	switch (cmd) {
509 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: /* fall through */
510 	case SNDRV_PCM_TRIGGER_RESUME: /* fall through */
511 	case SNDRV_PCM_TRIGGER_START:
512 		if (cpu_is_at32ap7000()) {
513 			retval = dw_dma_cyclic_start(chip->dma.tx_chan);
514 			if (retval)
515 				goto out;
516 		} else {
517 			ptcr = ATMEL_PDC_TXTEN;
518 		}
519 		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDTX;
520 		break;
521 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH: /* fall through */
522 	case SNDRV_PCM_TRIGGER_SUSPEND: /* fall through */
523 	case SNDRV_PCM_TRIGGER_STOP:
524 		if (cpu_is_at32ap7000())
525 			dw_dma_cyclic_stop(chip->dma.tx_chan);
526 		else
527 			ptcr |= ATMEL_PDC_TXTDIS;
528 		if (chip->opened <= 1)
529 			camr &= ~AC97C_CMR_CENA;
530 		break;
531 	default:
532 		retval = -EINVAL;
533 		goto out;
534 	}
535 
536 	ac97c_writel(chip, CAMR, camr);
537 	if (!cpu_is_at32ap7000())
538 		writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
539 out:
540 	return retval;
541 }
542 
543 static int
544 atmel_ac97c_capture_trigger(struct snd_pcm_substream *substream, int cmd)
545 {
546 	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
547 	unsigned long camr, ptcr = 0;
548 	int retval = 0;
549 
550 	camr = ac97c_readl(chip, CAMR);
551 	ptcr = readl(chip->regs + ATMEL_PDC_PTSR);
552 
553 	switch (cmd) {
554 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: /* fall through */
555 	case SNDRV_PCM_TRIGGER_RESUME: /* fall through */
556 	case SNDRV_PCM_TRIGGER_START:
557 		if (cpu_is_at32ap7000()) {
558 			retval = dw_dma_cyclic_start(chip->dma.rx_chan);
559 			if (retval)
560 				goto out;
561 		} else {
562 			ptcr = ATMEL_PDC_RXTEN;
563 		}
564 		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDRX;
565 		break;
566 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH: /* fall through */
567 	case SNDRV_PCM_TRIGGER_SUSPEND: /* fall through */
568 	case SNDRV_PCM_TRIGGER_STOP:
569 		if (cpu_is_at32ap7000())
570 			dw_dma_cyclic_stop(chip->dma.rx_chan);
571 		else
572 			ptcr |= (ATMEL_PDC_RXTDIS);
573 		if (chip->opened <= 1)
574 			camr &= ~AC97C_CMR_CENA;
575 		break;
576 	default:
577 		retval = -EINVAL;
578 		break;
579 	}
580 
581 	ac97c_writel(chip, CAMR, camr);
582 	if (!cpu_is_at32ap7000())
583 		writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
584 out:
585 	return retval;
586 }
587 
588 static snd_pcm_uframes_t
589 atmel_ac97c_playback_pointer(struct snd_pcm_substream *substream)
590 {
591 	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
592 	struct snd_pcm_runtime	*runtime = substream->runtime;
593 	snd_pcm_uframes_t	frames;
594 	unsigned long		bytes;
595 
596 	if (cpu_is_at32ap7000())
597 		bytes = dw_dma_get_src_addr(chip->dma.tx_chan);
598 	else
599 		bytes = readl(chip->regs + ATMEL_PDC_TPR);
600 	bytes -= runtime->dma_addr;
601 
602 	frames = bytes_to_frames(runtime, bytes);
603 	if (frames >= runtime->buffer_size)
604 		frames -= runtime->buffer_size;
605 	return frames;
606 }
607 
608 static snd_pcm_uframes_t
609 atmel_ac97c_capture_pointer(struct snd_pcm_substream *substream)
610 {
611 	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
612 	struct snd_pcm_runtime	*runtime = substream->runtime;
613 	snd_pcm_uframes_t	frames;
614 	unsigned long		bytes;
615 
616 	if (cpu_is_at32ap7000())
617 		bytes = dw_dma_get_dst_addr(chip->dma.rx_chan);
618 	else
619 		bytes = readl(chip->regs + ATMEL_PDC_RPR);
620 	bytes -= runtime->dma_addr;
621 
622 	frames = bytes_to_frames(runtime, bytes);
623 	if (frames >= runtime->buffer_size)
624 		frames -= runtime->buffer_size;
625 	return frames;
626 }
627 
628 static struct snd_pcm_ops atmel_ac97_playback_ops = {
629 	.open		= atmel_ac97c_playback_open,
630 	.close		= atmel_ac97c_playback_close,
631 	.ioctl		= snd_pcm_lib_ioctl,
632 	.hw_params	= atmel_ac97c_playback_hw_params,
633 	.hw_free	= atmel_ac97c_playback_hw_free,
634 	.prepare	= atmel_ac97c_playback_prepare,
635 	.trigger	= atmel_ac97c_playback_trigger,
636 	.pointer	= atmel_ac97c_playback_pointer,
637 };
638 
639 static struct snd_pcm_ops atmel_ac97_capture_ops = {
640 	.open		= atmel_ac97c_capture_open,
641 	.close		= atmel_ac97c_capture_close,
642 	.ioctl		= snd_pcm_lib_ioctl,
643 	.hw_params	= atmel_ac97c_capture_hw_params,
644 	.hw_free	= atmel_ac97c_capture_hw_free,
645 	.prepare	= atmel_ac97c_capture_prepare,
646 	.trigger	= atmel_ac97c_capture_trigger,
647 	.pointer	= atmel_ac97c_capture_pointer,
648 };
649 
650 static irqreturn_t atmel_ac97c_interrupt(int irq, void *dev)
651 {
652 	struct atmel_ac97c	*chip  = (struct atmel_ac97c *)dev;
653 	irqreturn_t		retval = IRQ_NONE;
654 	u32			sr     = ac97c_readl(chip, SR);
655 	u32			casr   = ac97c_readl(chip, CASR);
656 	u32			cosr   = ac97c_readl(chip, COSR);
657 	u32			camr   = ac97c_readl(chip, CAMR);
658 
659 	if (sr & AC97C_SR_CAEVT) {
660 		struct snd_pcm_runtime *runtime;
661 		int offset, next_period, block_size;
662 		dev_dbg(&chip->pdev->dev, "channel A event%s%s%s%s%s%s\n",
663 				casr & AC97C_CSR_OVRUN   ? " OVRUN"   : "",
664 				casr & AC97C_CSR_RXRDY   ? " RXRDY"   : "",
665 				casr & AC97C_CSR_UNRUN   ? " UNRUN"   : "",
666 				casr & AC97C_CSR_TXEMPTY ? " TXEMPTY" : "",
667 				casr & AC97C_CSR_TXRDY   ? " TXRDY"   : "",
668 				!casr                    ? " NONE"    : "");
669 		if (!cpu_is_at32ap7000()) {
670 			if ((casr & camr) & AC97C_CSR_ENDTX) {
671 				runtime = chip->playback_substream->runtime;
672 				block_size = frames_to_bytes(runtime,
673 						runtime->period_size);
674 				chip->playback_period++;
675 
676 				if (chip->playback_period == runtime->periods)
677 					chip->playback_period = 0;
678 				next_period = chip->playback_period + 1;
679 				if (next_period == runtime->periods)
680 					next_period = 0;
681 
682 				offset = block_size * next_period;
683 
684 				writel(runtime->dma_addr + offset,
685 						chip->regs + ATMEL_PDC_TNPR);
686 				writel(block_size / 2,
687 						chip->regs + ATMEL_PDC_TNCR);
688 
689 				snd_pcm_period_elapsed(
690 						chip->playback_substream);
691 			}
692 			if ((casr & camr) & AC97C_CSR_ENDRX) {
693 				runtime = chip->capture_substream->runtime;
694 				block_size = frames_to_bytes(runtime,
695 						runtime->period_size);
696 				chip->capture_period++;
697 
698 				if (chip->capture_period == runtime->periods)
699 					chip->capture_period = 0;
700 				next_period = chip->capture_period + 1;
701 				if (next_period == runtime->periods)
702 					next_period = 0;
703 
704 				offset = block_size * next_period;
705 
706 				writel(runtime->dma_addr + offset,
707 						chip->regs + ATMEL_PDC_RNPR);
708 				writel(block_size / 2,
709 						chip->regs + ATMEL_PDC_RNCR);
710 				snd_pcm_period_elapsed(chip->capture_substream);
711 			}
712 		}
713 		retval = IRQ_HANDLED;
714 	}
715 
716 	if (sr & AC97C_SR_COEVT) {
717 		dev_info(&chip->pdev->dev, "codec channel event%s%s%s%s%s\n",
718 				cosr & AC97C_CSR_OVRUN   ? " OVRUN"   : "",
719 				cosr & AC97C_CSR_RXRDY   ? " RXRDY"   : "",
720 				cosr & AC97C_CSR_TXEMPTY ? " TXEMPTY" : "",
721 				cosr & AC97C_CSR_TXRDY   ? " TXRDY"   : "",
722 				!cosr                    ? " NONE"    : "");
723 		retval = IRQ_HANDLED;
724 	}
725 
726 	if (retval == IRQ_NONE) {
727 		dev_err(&chip->pdev->dev, "spurious interrupt sr 0x%08x "
728 				"casr 0x%08x cosr 0x%08x\n", sr, casr, cosr);
729 	}
730 
731 	return retval;
732 }
733 
734 static struct ac97_pcm at91_ac97_pcm_defs[] = {
735 	/* Playback */
736 	{
737 		.exclusive = 1,
738 		.r = { {
739 			.slots = ((1 << AC97_SLOT_PCM_LEFT)
740 				  | (1 << AC97_SLOT_PCM_RIGHT)),
741 		} },
742 	},
743 	/* PCM in */
744 	{
745 		.stream = 1,
746 		.exclusive = 1,
747 		.r = { {
748 			.slots = ((1 << AC97_SLOT_PCM_LEFT)
749 					| (1 << AC97_SLOT_PCM_RIGHT)),
750 		} }
751 	},
752 	/* Mic in */
753 	{
754 		.stream = 1,
755 		.exclusive = 1,
756 		.r = { {
757 			.slots = (1<<AC97_SLOT_MIC),
758 		} }
759 	},
760 };
761 
762 static int atmel_ac97c_pcm_new(struct atmel_ac97c *chip)
763 {
764 	struct snd_pcm		*pcm;
765 	struct snd_pcm_hardware	hw = atmel_ac97c_hw;
766 	int			capture, playback, retval, err;
767 
768 	capture = test_bit(DMA_RX_CHAN_PRESENT, &chip->flags);
769 	playback = test_bit(DMA_TX_CHAN_PRESENT, &chip->flags);
770 
771 	if (!cpu_is_at32ap7000()) {
772 		err = snd_ac97_pcm_assign(chip->ac97_bus,
773 				ARRAY_SIZE(at91_ac97_pcm_defs),
774 				at91_ac97_pcm_defs);
775 		if (err)
776 			return err;
777 	}
778 	retval = snd_pcm_new(chip->card, chip->card->shortname,
779 			0, playback, capture, &pcm);
780 	if (retval)
781 		return retval;
782 
783 	if (capture)
784 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
785 				&atmel_ac97_capture_ops);
786 	if (playback)
787 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
788 				&atmel_ac97_playback_ops);
789 
790 	retval = snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
791 			&chip->pdev->dev, hw.periods_min * hw.period_bytes_min,
792 			hw.buffer_bytes_max);
793 	if (retval)
794 		return retval;
795 
796 	pcm->private_data = chip;
797 	pcm->info_flags = 0;
798 	strcpy(pcm->name, chip->card->shortname);
799 	chip->pcm = pcm;
800 
801 	return 0;
802 }
803 
804 static int atmel_ac97c_mixer_new(struct atmel_ac97c *chip)
805 {
806 	struct snd_ac97_template template;
807 	memset(&template, 0, sizeof(template));
808 	template.private_data = chip;
809 	return snd_ac97_mixer(chip->ac97_bus, &template, &chip->ac97);
810 }
811 
812 static void atmel_ac97c_write(struct snd_ac97 *ac97, unsigned short reg,
813 		unsigned short val)
814 {
815 	struct atmel_ac97c *chip = get_chip(ac97);
816 	unsigned long word;
817 	int timeout = 40;
818 
819 	word = (reg & 0x7f) << 16 | val;
820 
821 	do {
822 		if (ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) {
823 			ac97c_writel(chip, COTHR, word);
824 			return;
825 		}
826 		udelay(1);
827 	} while (--timeout);
828 
829 	dev_dbg(&chip->pdev->dev, "codec write timeout\n");
830 }
831 
832 static unsigned short atmel_ac97c_read(struct snd_ac97 *ac97,
833 		unsigned short reg)
834 {
835 	struct atmel_ac97c *chip = get_chip(ac97);
836 	unsigned long word;
837 	int timeout = 40;
838 	int write = 10;
839 
840 	word = (0x80 | (reg & 0x7f)) << 16;
841 
842 	if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0)
843 		ac97c_readl(chip, CORHR);
844 
845 retry_write:
846 	timeout = 40;
847 
848 	do {
849 		if ((ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) != 0) {
850 			ac97c_writel(chip, COTHR, word);
851 			goto read_reg;
852 		}
853 		udelay(10);
854 	} while (--timeout);
855 
856 	if (!--write)
857 		goto timed_out;
858 	goto retry_write;
859 
860 read_reg:
861 	do {
862 		if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0) {
863 			unsigned short val = ac97c_readl(chip, CORHR);
864 			return val;
865 		}
866 		udelay(10);
867 	} while (--timeout);
868 
869 	if (!--write)
870 		goto timed_out;
871 	goto retry_write;
872 
873 timed_out:
874 	dev_dbg(&chip->pdev->dev, "codec read timeout\n");
875 	return 0xffff;
876 }
877 
878 static bool filter(struct dma_chan *chan, void *slave)
879 {
880 	struct dw_dma_slave *dws = slave;
881 
882 	if (dws->dma_dev == chan->device->dev) {
883 		chan->private = dws;
884 		return true;
885 	} else
886 		return false;
887 }
888 
889 static void atmel_ac97c_reset(struct atmel_ac97c *chip)
890 {
891 	ac97c_writel(chip, MR,   0);
892 	ac97c_writel(chip, MR,   AC97C_MR_ENA);
893 	ac97c_writel(chip, CAMR, 0);
894 	ac97c_writel(chip, COMR, 0);
895 
896 	if (gpio_is_valid(chip->reset_pin)) {
897 		gpio_set_value(chip->reset_pin, 0);
898 		/* AC97 v2.2 specifications says minimum 1 us. */
899 		udelay(2);
900 		gpio_set_value(chip->reset_pin, 1);
901 	} else {
902 		ac97c_writel(chip, MR, AC97C_MR_WRST | AC97C_MR_ENA);
903 		udelay(2);
904 		ac97c_writel(chip, MR, AC97C_MR_ENA);
905 	}
906 }
907 
908 #ifdef CONFIG_OF
909 static const struct of_device_id atmel_ac97c_dt_ids[] = {
910 	{ .compatible = "atmel,at91sam9263-ac97c", },
911 	{ }
912 };
913 MODULE_DEVICE_TABLE(of, atmel_ac97c_dt_ids);
914 
915 static struct ac97c_platform_data *atmel_ac97c_probe_dt(struct device *dev)
916 {
917 	struct ac97c_platform_data *pdata;
918 	struct device_node *node = dev->of_node;
919 
920 	if (!node) {
921 		dev_err(dev, "Device does not have associated DT data\n");
922 		return ERR_PTR(-EINVAL);
923 	}
924 
925 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
926 	if (!pdata)
927 		return ERR_PTR(-ENOMEM);
928 
929 	pdata->reset_pin = of_get_named_gpio(dev->of_node, "ac97-gpios", 2);
930 
931 	return pdata;
932 }
933 #else
934 static struct ac97c_platform_data *atmel_ac97c_probe_dt(struct device *dev)
935 {
936 	dev_err(dev, "no platform data defined\n");
937 	return ERR_PTR(-ENXIO);
938 }
939 #endif
940 
941 static int atmel_ac97c_probe(struct platform_device *pdev)
942 {
943 	struct snd_card			*card;
944 	struct atmel_ac97c		*chip;
945 	struct resource			*regs;
946 	struct ac97c_platform_data	*pdata;
947 	struct clk			*pclk;
948 	static struct snd_ac97_bus_ops	ops = {
949 		.write	= atmel_ac97c_write,
950 		.read	= atmel_ac97c_read,
951 	};
952 	int				retval;
953 	int				irq;
954 
955 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
956 	if (!regs) {
957 		dev_dbg(&pdev->dev, "no memory resource\n");
958 		return -ENXIO;
959 	}
960 
961 	pdata = dev_get_platdata(&pdev->dev);
962 	if (!pdata) {
963 		pdata = atmel_ac97c_probe_dt(&pdev->dev);
964 		if (IS_ERR(pdata))
965 			return PTR_ERR(pdata);
966 	}
967 
968 	irq = platform_get_irq(pdev, 0);
969 	if (irq < 0) {
970 		dev_dbg(&pdev->dev, "could not get irq\n");
971 		return -ENXIO;
972 	}
973 
974 	if (cpu_is_at32ap7000()) {
975 		pclk = clk_get(&pdev->dev, "pclk");
976 	} else {
977 		pclk = clk_get(&pdev->dev, "ac97_clk");
978 	}
979 
980 	if (IS_ERR(pclk)) {
981 		dev_dbg(&pdev->dev, "no peripheral clock\n");
982 		return PTR_ERR(pclk);
983 	}
984 	clk_prepare_enable(pclk);
985 
986 	retval = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1,
987 			      SNDRV_DEFAULT_STR1, THIS_MODULE,
988 			      sizeof(struct atmel_ac97c), &card);
989 	if (retval) {
990 		dev_dbg(&pdev->dev, "could not create sound card device\n");
991 		goto err_snd_card_new;
992 	}
993 
994 	chip = get_chip(card);
995 
996 	retval = request_irq(irq, atmel_ac97c_interrupt, 0, "AC97C", chip);
997 	if (retval) {
998 		dev_dbg(&pdev->dev, "unable to request irq %d\n", irq);
999 		goto err_request_irq;
1000 	}
1001 	chip->irq = irq;
1002 
1003 	spin_lock_init(&chip->lock);
1004 
1005 	strcpy(card->driver, "Atmel AC97C");
1006 	strcpy(card->shortname, "Atmel AC97C");
1007 	sprintf(card->longname, "Atmel AC97 controller");
1008 
1009 	chip->card = card;
1010 	chip->pclk = pclk;
1011 	chip->pdev = pdev;
1012 	chip->regs = ioremap(regs->start, resource_size(regs));
1013 
1014 	if (!chip->regs) {
1015 		dev_dbg(&pdev->dev, "could not remap register memory\n");
1016 		retval = -ENOMEM;
1017 		goto err_ioremap;
1018 	}
1019 
1020 	if (gpio_is_valid(pdata->reset_pin)) {
1021 		if (gpio_request(pdata->reset_pin, "reset_pin")) {
1022 			dev_dbg(&pdev->dev, "reset pin not available\n");
1023 			chip->reset_pin = -ENODEV;
1024 		} else {
1025 			gpio_direction_output(pdata->reset_pin, 1);
1026 			chip->reset_pin = pdata->reset_pin;
1027 		}
1028 	} else {
1029 		chip->reset_pin = -EINVAL;
1030 	}
1031 
1032 	atmel_ac97c_reset(chip);
1033 
1034 	/* Enable overrun interrupt from codec channel */
1035 	ac97c_writel(chip, COMR, AC97C_CSR_OVRUN);
1036 	ac97c_writel(chip, IER, ac97c_readl(chip, IMR) | AC97C_SR_COEVT);
1037 
1038 	retval = snd_ac97_bus(card, 0, &ops, chip, &chip->ac97_bus);
1039 	if (retval) {
1040 		dev_dbg(&pdev->dev, "could not register on ac97 bus\n");
1041 		goto err_ac97_bus;
1042 	}
1043 
1044 	retval = atmel_ac97c_mixer_new(chip);
1045 	if (retval) {
1046 		dev_dbg(&pdev->dev, "could not register ac97 mixer\n");
1047 		goto err_ac97_bus;
1048 	}
1049 
1050 	if (cpu_is_at32ap7000()) {
1051 		if (pdata->rx_dws.dma_dev) {
1052 			dma_cap_mask_t mask;
1053 
1054 			dma_cap_zero(mask);
1055 			dma_cap_set(DMA_SLAVE, mask);
1056 
1057 			chip->dma.rx_chan = dma_request_channel(mask, filter,
1058 								&pdata->rx_dws);
1059 			if (chip->dma.rx_chan) {
1060 				struct dma_slave_config dma_conf = {
1061 					.src_addr = regs->start + AC97C_CARHR +
1062 						2,
1063 					.src_addr_width =
1064 						DMA_SLAVE_BUSWIDTH_2_BYTES,
1065 					.src_maxburst = 1,
1066 					.dst_maxburst = 1,
1067 					.direction = DMA_DEV_TO_MEM,
1068 					.device_fc = false,
1069 				};
1070 
1071 				dmaengine_slave_config(chip->dma.rx_chan,
1072 						&dma_conf);
1073 			}
1074 
1075 			dev_info(&chip->pdev->dev, "using %s for DMA RX\n",
1076 				dev_name(&chip->dma.rx_chan->dev->device));
1077 			set_bit(DMA_RX_CHAN_PRESENT, &chip->flags);
1078 		}
1079 
1080 		if (pdata->tx_dws.dma_dev) {
1081 			dma_cap_mask_t mask;
1082 
1083 			dma_cap_zero(mask);
1084 			dma_cap_set(DMA_SLAVE, mask);
1085 
1086 			chip->dma.tx_chan = dma_request_channel(mask, filter,
1087 								&pdata->tx_dws);
1088 			if (chip->dma.tx_chan) {
1089 				struct dma_slave_config dma_conf = {
1090 					.dst_addr = regs->start + AC97C_CATHR +
1091 						2,
1092 					.dst_addr_width =
1093 						DMA_SLAVE_BUSWIDTH_2_BYTES,
1094 					.src_maxburst = 1,
1095 					.dst_maxburst = 1,
1096 					.direction = DMA_MEM_TO_DEV,
1097 					.device_fc = false,
1098 				};
1099 
1100 				dmaengine_slave_config(chip->dma.tx_chan,
1101 						&dma_conf);
1102 			}
1103 
1104 			dev_info(&chip->pdev->dev, "using %s for DMA TX\n",
1105 				dev_name(&chip->dma.tx_chan->dev->device));
1106 			set_bit(DMA_TX_CHAN_PRESENT, &chip->flags);
1107 		}
1108 
1109 		if (!test_bit(DMA_RX_CHAN_PRESENT, &chip->flags) &&
1110 				!test_bit(DMA_TX_CHAN_PRESENT, &chip->flags)) {
1111 			dev_dbg(&pdev->dev, "DMA not available\n");
1112 			retval = -ENODEV;
1113 			goto err_dma;
1114 		}
1115 	} else {
1116 		/* Just pretend that we have DMA channel(for at91 i is actually
1117 		 * the PDC) */
1118 		set_bit(DMA_RX_CHAN_PRESENT, &chip->flags);
1119 		set_bit(DMA_TX_CHAN_PRESENT, &chip->flags);
1120 	}
1121 
1122 	retval = atmel_ac97c_pcm_new(chip);
1123 	if (retval) {
1124 		dev_dbg(&pdev->dev, "could not register ac97 pcm device\n");
1125 		goto err_dma;
1126 	}
1127 
1128 	retval = snd_card_register(card);
1129 	if (retval) {
1130 		dev_dbg(&pdev->dev, "could not register sound card\n");
1131 		goto err_dma;
1132 	}
1133 
1134 	platform_set_drvdata(pdev, card);
1135 
1136 	dev_info(&pdev->dev, "Atmel AC97 controller at 0x%p, irq = %d\n",
1137 			chip->regs, irq);
1138 
1139 	return 0;
1140 
1141 err_dma:
1142 	if (cpu_is_at32ap7000()) {
1143 		if (test_bit(DMA_RX_CHAN_PRESENT, &chip->flags))
1144 			dma_release_channel(chip->dma.rx_chan);
1145 		if (test_bit(DMA_TX_CHAN_PRESENT, &chip->flags))
1146 			dma_release_channel(chip->dma.tx_chan);
1147 		clear_bit(DMA_RX_CHAN_PRESENT, &chip->flags);
1148 		clear_bit(DMA_TX_CHAN_PRESENT, &chip->flags);
1149 		chip->dma.rx_chan = NULL;
1150 		chip->dma.tx_chan = NULL;
1151 	}
1152 err_ac97_bus:
1153 	if (gpio_is_valid(chip->reset_pin))
1154 		gpio_free(chip->reset_pin);
1155 
1156 	iounmap(chip->regs);
1157 err_ioremap:
1158 	free_irq(irq, chip);
1159 err_request_irq:
1160 	snd_card_free(card);
1161 err_snd_card_new:
1162 	clk_disable_unprepare(pclk);
1163 	clk_put(pclk);
1164 	return retval;
1165 }
1166 
1167 #ifdef CONFIG_PM_SLEEP
1168 static int atmel_ac97c_suspend(struct device *pdev)
1169 {
1170 	struct snd_card *card = dev_get_drvdata(pdev);
1171 	struct atmel_ac97c *chip = card->private_data;
1172 
1173 	if (cpu_is_at32ap7000()) {
1174 		if (test_bit(DMA_RX_READY, &chip->flags))
1175 			dw_dma_cyclic_stop(chip->dma.rx_chan);
1176 		if (test_bit(DMA_TX_READY, &chip->flags))
1177 			dw_dma_cyclic_stop(chip->dma.tx_chan);
1178 	}
1179 	clk_disable_unprepare(chip->pclk);
1180 
1181 	return 0;
1182 }
1183 
1184 static int atmel_ac97c_resume(struct device *pdev)
1185 {
1186 	struct snd_card *card = dev_get_drvdata(pdev);
1187 	struct atmel_ac97c *chip = card->private_data;
1188 
1189 	clk_prepare_enable(chip->pclk);
1190 	if (cpu_is_at32ap7000()) {
1191 		if (test_bit(DMA_RX_READY, &chip->flags))
1192 			dw_dma_cyclic_start(chip->dma.rx_chan);
1193 		if (test_bit(DMA_TX_READY, &chip->flags))
1194 			dw_dma_cyclic_start(chip->dma.tx_chan);
1195 	}
1196 	return 0;
1197 }
1198 
1199 static SIMPLE_DEV_PM_OPS(atmel_ac97c_pm, atmel_ac97c_suspend, atmel_ac97c_resume);
1200 #define ATMEL_AC97C_PM_OPS	&atmel_ac97c_pm
1201 #else
1202 #define ATMEL_AC97C_PM_OPS	NULL
1203 #endif
1204 
1205 static int atmel_ac97c_remove(struct platform_device *pdev)
1206 {
1207 	struct snd_card *card = platform_get_drvdata(pdev);
1208 	struct atmel_ac97c *chip = get_chip(card);
1209 
1210 	if (gpio_is_valid(chip->reset_pin))
1211 		gpio_free(chip->reset_pin);
1212 
1213 	ac97c_writel(chip, CAMR, 0);
1214 	ac97c_writel(chip, COMR, 0);
1215 	ac97c_writel(chip, MR,   0);
1216 
1217 	clk_disable_unprepare(chip->pclk);
1218 	clk_put(chip->pclk);
1219 	iounmap(chip->regs);
1220 	free_irq(chip->irq, chip);
1221 
1222 	if (cpu_is_at32ap7000()) {
1223 		if (test_bit(DMA_RX_CHAN_PRESENT, &chip->flags))
1224 			dma_release_channel(chip->dma.rx_chan);
1225 		if (test_bit(DMA_TX_CHAN_PRESENT, &chip->flags))
1226 			dma_release_channel(chip->dma.tx_chan);
1227 		clear_bit(DMA_RX_CHAN_PRESENT, &chip->flags);
1228 		clear_bit(DMA_TX_CHAN_PRESENT, &chip->flags);
1229 		chip->dma.rx_chan = NULL;
1230 		chip->dma.tx_chan = NULL;
1231 	}
1232 
1233 	snd_card_free(card);
1234 
1235 	return 0;
1236 }
1237 
1238 static struct platform_driver atmel_ac97c_driver = {
1239 	.probe		= atmel_ac97c_probe,
1240 	.remove		= atmel_ac97c_remove,
1241 	.driver		= {
1242 		.name	= "atmel_ac97c",
1243 		.pm	= ATMEL_AC97C_PM_OPS,
1244 		.of_match_table = of_match_ptr(atmel_ac97c_dt_ids),
1245 	},
1246 };
1247 module_platform_driver(atmel_ac97c_driver);
1248 
1249 MODULE_LICENSE("GPL");
1250 MODULE_DESCRIPTION("Driver for Atmel AC97 controller");
1251 MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
1252