xref: /kernel/linux/linux-5.10/sound/atmel/ac97c.c (revision 8c2ecf20)
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 */
33static DEFINE_MUTEX(opened_mutex);
34
35struct 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
64static 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
86static 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
105static 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
124static 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
141static 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
158static 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
163	/* Set restrictions to params. */
164	mutex_lock(&opened_mutex);
165	chip->cur_rate = params_rate(hw_params);
166	chip->cur_format = params_format(hw_params);
167	mutex_unlock(&opened_mutex);
168
169	return 0;
170}
171
172static int atmel_ac97c_capture_hw_params(struct snd_pcm_substream *substream,
173		struct snd_pcm_hw_params *hw_params)
174{
175	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
176
177	/* Set restrictions to params. */
178	mutex_lock(&opened_mutex);
179	chip->cur_rate = params_rate(hw_params);
180	chip->cur_format = params_format(hw_params);
181	mutex_unlock(&opened_mutex);
182
183	return 0;
184}
185
186static int atmel_ac97c_playback_prepare(struct snd_pcm_substream *substream)
187{
188	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
189	struct snd_pcm_runtime *runtime = substream->runtime;
190	int block_size = frames_to_bytes(runtime, runtime->period_size);
191	unsigned long word = ac97c_readl(chip, OCA);
192	int retval;
193
194	chip->playback_period = 0;
195	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
196
197	/* assign channels to AC97C channel A */
198	switch (runtime->channels) {
199	case 1:
200		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
201		break;
202	case 2:
203		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
204			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
205		break;
206	default:
207		/* TODO: support more than two channels */
208		return -EINVAL;
209	}
210	ac97c_writel(chip, OCA, word);
211
212	/* configure sample format and size */
213	word = ac97c_readl(chip, CAMR);
214	if (chip->opened <= 1)
215		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
216	else
217		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
218
219	switch (runtime->format) {
220	case SNDRV_PCM_FORMAT_S16_LE:
221		break;
222	case SNDRV_PCM_FORMAT_S16_BE:
223		word &= ~(AC97C_CMR_CEM_LITTLE);
224		break;
225	default:
226		word = ac97c_readl(chip, OCA);
227		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
228		ac97c_writel(chip, OCA, word);
229		return -EINVAL;
230	}
231
232	/* Enable underrun interrupt on channel A */
233	word |= AC97C_CSR_UNRUN;
234
235	ac97c_writel(chip, CAMR, word);
236
237	/* Enable channel A event interrupt */
238	word = ac97c_readl(chip, IMR);
239	word |= AC97C_SR_CAEVT;
240	ac97c_writel(chip, IER, word);
241
242	/* set variable rate if needed */
243	if (runtime->rate != 48000) {
244		word = ac97c_readl(chip, MR);
245		word |= AC97C_MR_VRA;
246		ac97c_writel(chip, MR, word);
247	} else {
248		word = ac97c_readl(chip, MR);
249		word &= ~(AC97C_MR_VRA);
250		ac97c_writel(chip, MR, word);
251	}
252
253	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_FRONT_DAC_RATE,
254			runtime->rate);
255	if (retval)
256		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
257				runtime->rate);
258
259	/* Initialize and start the PDC */
260	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_TPR);
261	writel(block_size / 2, chip->regs + ATMEL_PDC_TCR);
262	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_TNPR);
263	writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
264
265	return retval;
266}
267
268static int atmel_ac97c_capture_prepare(struct snd_pcm_substream *substream)
269{
270	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
271	struct snd_pcm_runtime *runtime = substream->runtime;
272	int block_size = frames_to_bytes(runtime, runtime->period_size);
273	unsigned long word = ac97c_readl(chip, ICA);
274	int retval;
275
276	chip->capture_period = 0;
277	word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
278
279	/* assign channels to AC97C channel A */
280	switch (runtime->channels) {
281	case 1:
282		word |= AC97C_CH_ASSIGN(PCM_LEFT, A);
283		break;
284	case 2:
285		word |= AC97C_CH_ASSIGN(PCM_LEFT, A)
286			| AC97C_CH_ASSIGN(PCM_RIGHT, A);
287		break;
288	default:
289		/* TODO: support more than two channels */
290		return -EINVAL;
291	}
292	ac97c_writel(chip, ICA, word);
293
294	/* configure sample format and size */
295	word = ac97c_readl(chip, CAMR);
296	if (chip->opened <= 1)
297		word = AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
298	else
299		word |= AC97C_CMR_DMAEN | AC97C_CMR_SIZE_16;
300
301	switch (runtime->format) {
302	case SNDRV_PCM_FORMAT_S16_LE:
303		break;
304	case SNDRV_PCM_FORMAT_S16_BE:
305		word &= ~(AC97C_CMR_CEM_LITTLE);
306		break;
307	default:
308		word = ac97c_readl(chip, ICA);
309		word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
310		ac97c_writel(chip, ICA, word);
311		return -EINVAL;
312	}
313
314	/* Enable overrun interrupt on channel A */
315	word |= AC97C_CSR_OVRUN;
316
317	ac97c_writel(chip, CAMR, word);
318
319	/* Enable channel A event interrupt */
320	word = ac97c_readl(chip, IMR);
321	word |= AC97C_SR_CAEVT;
322	ac97c_writel(chip, IER, word);
323
324	/* set variable rate if needed */
325	if (runtime->rate != 48000) {
326		word = ac97c_readl(chip, MR);
327		word |= AC97C_MR_VRA;
328		ac97c_writel(chip, MR, word);
329	} else {
330		word = ac97c_readl(chip, MR);
331		word &= ~(AC97C_MR_VRA);
332		ac97c_writel(chip, MR, word);
333	}
334
335	retval = snd_ac97_set_rate(chip->ac97, AC97_PCM_LR_ADC_RATE,
336			runtime->rate);
337	if (retval)
338		dev_dbg(&chip->pdev->dev, "could not set rate %d Hz\n",
339				runtime->rate);
340
341	/* Initialize and start the PDC */
342	writel(runtime->dma_addr, chip->regs + ATMEL_PDC_RPR);
343	writel(block_size / 2, chip->regs + ATMEL_PDC_RCR);
344	writel(runtime->dma_addr + block_size, chip->regs + ATMEL_PDC_RNPR);
345	writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
346
347	return retval;
348}
349
350static int
351atmel_ac97c_playback_trigger(struct snd_pcm_substream *substream, int cmd)
352{
353	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
354	unsigned long camr, ptcr = 0;
355
356	camr = ac97c_readl(chip, CAMR);
357
358	switch (cmd) {
359	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
360	case SNDRV_PCM_TRIGGER_RESUME:
361	case SNDRV_PCM_TRIGGER_START:
362		ptcr = ATMEL_PDC_TXTEN;
363		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDTX;
364		break;
365	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
366	case SNDRV_PCM_TRIGGER_SUSPEND:
367	case SNDRV_PCM_TRIGGER_STOP:
368		ptcr |= ATMEL_PDC_TXTDIS;
369		if (chip->opened <= 1)
370			camr &= ~AC97C_CMR_CENA;
371		break;
372	default:
373		return -EINVAL;
374	}
375
376	ac97c_writel(chip, CAMR, camr);
377	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
378	return 0;
379}
380
381static int
382atmel_ac97c_capture_trigger(struct snd_pcm_substream *substream, int cmd)
383{
384	struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
385	unsigned long camr, ptcr = 0;
386
387	camr = ac97c_readl(chip, CAMR);
388	ptcr = readl(chip->regs + ATMEL_PDC_PTSR);
389
390	switch (cmd) {
391	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
392	case SNDRV_PCM_TRIGGER_RESUME:
393	case SNDRV_PCM_TRIGGER_START:
394		ptcr = ATMEL_PDC_RXTEN;
395		camr |= AC97C_CMR_CENA | AC97C_CSR_ENDRX;
396		break;
397	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
398	case SNDRV_PCM_TRIGGER_SUSPEND:
399	case SNDRV_PCM_TRIGGER_STOP:
400		ptcr |= ATMEL_PDC_RXTDIS;
401		if (chip->opened <= 1)
402			camr &= ~AC97C_CMR_CENA;
403		break;
404	default:
405		return -EINVAL;
406	}
407
408	ac97c_writel(chip, CAMR, camr);
409	writel(ptcr, chip->regs + ATMEL_PDC_PTCR);
410	return 0;
411}
412
413static snd_pcm_uframes_t
414atmel_ac97c_playback_pointer(struct snd_pcm_substream *substream)
415{
416	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
417	struct snd_pcm_runtime	*runtime = substream->runtime;
418	snd_pcm_uframes_t	frames;
419	unsigned long		bytes;
420
421	bytes = readl(chip->regs + ATMEL_PDC_TPR);
422	bytes -= runtime->dma_addr;
423
424	frames = bytes_to_frames(runtime, bytes);
425	if (frames >= runtime->buffer_size)
426		frames -= runtime->buffer_size;
427	return frames;
428}
429
430static snd_pcm_uframes_t
431atmel_ac97c_capture_pointer(struct snd_pcm_substream *substream)
432{
433	struct atmel_ac97c	*chip = snd_pcm_substream_chip(substream);
434	struct snd_pcm_runtime	*runtime = substream->runtime;
435	snd_pcm_uframes_t	frames;
436	unsigned long		bytes;
437
438	bytes = readl(chip->regs + ATMEL_PDC_RPR);
439	bytes -= runtime->dma_addr;
440
441	frames = bytes_to_frames(runtime, bytes);
442	if (frames >= runtime->buffer_size)
443		frames -= runtime->buffer_size;
444	return frames;
445}
446
447static const struct snd_pcm_ops atmel_ac97_playback_ops = {
448	.open		= atmel_ac97c_playback_open,
449	.close		= atmel_ac97c_playback_close,
450	.hw_params	= atmel_ac97c_playback_hw_params,
451	.prepare	= atmel_ac97c_playback_prepare,
452	.trigger	= atmel_ac97c_playback_trigger,
453	.pointer	= atmel_ac97c_playback_pointer,
454};
455
456static const struct snd_pcm_ops atmel_ac97_capture_ops = {
457	.open		= atmel_ac97c_capture_open,
458	.close		= atmel_ac97c_capture_close,
459	.hw_params	= atmel_ac97c_capture_hw_params,
460	.prepare	= atmel_ac97c_capture_prepare,
461	.trigger	= atmel_ac97c_capture_trigger,
462	.pointer	= atmel_ac97c_capture_pointer,
463};
464
465static irqreturn_t atmel_ac97c_interrupt(int irq, void *dev)
466{
467	struct atmel_ac97c	*chip  = (struct atmel_ac97c *)dev;
468	irqreturn_t		retval = IRQ_NONE;
469	u32			sr     = ac97c_readl(chip, SR);
470	u32			casr   = ac97c_readl(chip, CASR);
471	u32			cosr   = ac97c_readl(chip, COSR);
472	u32			camr   = ac97c_readl(chip, CAMR);
473
474	if (sr & AC97C_SR_CAEVT) {
475		struct snd_pcm_runtime *runtime;
476		int offset, next_period, block_size;
477		dev_dbg(&chip->pdev->dev, "channel A event%s%s%s%s%s%s\n",
478			(casr & AC97C_CSR_OVRUN)   ? " OVRUN"   : "",
479			(casr & AC97C_CSR_RXRDY)   ? " RXRDY"   : "",
480			(casr & AC97C_CSR_UNRUN)   ? " UNRUN"   : "",
481			(casr & AC97C_CSR_TXEMPTY) ? " TXEMPTY" : "",
482			(casr & AC97C_CSR_TXRDY)   ? " TXRDY"   : "",
483			!casr                      ? " NONE"    : "");
484		if ((casr & camr) & AC97C_CSR_ENDTX) {
485			runtime = chip->playback_substream->runtime;
486			block_size = frames_to_bytes(runtime, runtime->period_size);
487			chip->playback_period++;
488
489			if (chip->playback_period == runtime->periods)
490				chip->playback_period = 0;
491			next_period = chip->playback_period + 1;
492			if (next_period == runtime->periods)
493				next_period = 0;
494
495			offset = block_size * next_period;
496
497			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_TNPR);
498			writel(block_size / 2, chip->regs + ATMEL_PDC_TNCR);
499
500			snd_pcm_period_elapsed(chip->playback_substream);
501		}
502		if ((casr & camr) & AC97C_CSR_ENDRX) {
503			runtime = chip->capture_substream->runtime;
504			block_size = frames_to_bytes(runtime, runtime->period_size);
505			chip->capture_period++;
506
507			if (chip->capture_period == runtime->periods)
508				chip->capture_period = 0;
509			next_period = chip->capture_period + 1;
510			if (next_period == runtime->periods)
511				next_period = 0;
512
513			offset = block_size * next_period;
514
515			writel(runtime->dma_addr + offset, chip->regs + ATMEL_PDC_RNPR);
516			writel(block_size / 2, chip->regs + ATMEL_PDC_RNCR);
517			snd_pcm_period_elapsed(chip->capture_substream);
518		}
519		retval = IRQ_HANDLED;
520	}
521
522	if (sr & AC97C_SR_COEVT) {
523		dev_info(&chip->pdev->dev, "codec channel event%s%s%s%s%s\n",
524			 (cosr & AC97C_CSR_OVRUN)   ? " OVRUN"   : "",
525			 (cosr & AC97C_CSR_RXRDY)   ? " RXRDY"   : "",
526			 (cosr & AC97C_CSR_TXEMPTY) ? " TXEMPTY" : "",
527			 (cosr & AC97C_CSR_TXRDY)   ? " TXRDY"   : "",
528			 !cosr                      ? " NONE"    : "");
529		retval = IRQ_HANDLED;
530	}
531
532	if (retval == IRQ_NONE) {
533		dev_err(&chip->pdev->dev, "spurious interrupt sr 0x%08x "
534				"casr 0x%08x cosr 0x%08x\n", sr, casr, cosr);
535	}
536
537	return retval;
538}
539
540static const struct ac97_pcm at91_ac97_pcm_defs[] = {
541	/* Playback */
542	{
543		.exclusive = 1,
544		.r = { {
545			.slots = ((1 << AC97_SLOT_PCM_LEFT)
546				  | (1 << AC97_SLOT_PCM_RIGHT)),
547		} },
548	},
549	/* PCM in */
550	{
551		.stream = 1,
552		.exclusive = 1,
553		.r = { {
554			.slots = ((1 << AC97_SLOT_PCM_LEFT)
555					| (1 << AC97_SLOT_PCM_RIGHT)),
556		} }
557	},
558	/* Mic in */
559	{
560		.stream = 1,
561		.exclusive = 1,
562		.r = { {
563			.slots = (1<<AC97_SLOT_MIC),
564		} }
565	},
566};
567
568static int atmel_ac97c_pcm_new(struct atmel_ac97c *chip)
569{
570	struct snd_pcm		*pcm;
571	struct snd_pcm_hardware	hw = atmel_ac97c_hw;
572	int			retval;
573
574	retval = snd_ac97_pcm_assign(chip->ac97_bus,
575				     ARRAY_SIZE(at91_ac97_pcm_defs),
576				     at91_ac97_pcm_defs);
577	if (retval)
578		return retval;
579
580	retval = snd_pcm_new(chip->card, chip->card->shortname, 0, 1, 1, &pcm);
581	if (retval)
582		return retval;
583
584	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &atmel_ac97_capture_ops);
585	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &atmel_ac97_playback_ops);
586
587	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
588			&chip->pdev->dev, hw.periods_min * hw.period_bytes_min,
589			hw.buffer_bytes_max);
590
591	pcm->private_data = chip;
592	pcm->info_flags = 0;
593	strcpy(pcm->name, chip->card->shortname);
594	chip->pcm = pcm;
595
596	return 0;
597}
598
599static int atmel_ac97c_mixer_new(struct atmel_ac97c *chip)
600{
601	struct snd_ac97_template template;
602	memset(&template, 0, sizeof(template));
603	template.private_data = chip;
604	return snd_ac97_mixer(chip->ac97_bus, &template, &chip->ac97);
605}
606
607static void atmel_ac97c_write(struct snd_ac97 *ac97, unsigned short reg,
608		unsigned short val)
609{
610	struct atmel_ac97c *chip = get_chip(ac97);
611	unsigned long word;
612	int timeout = 40;
613
614	word = (reg & 0x7f) << 16 | val;
615
616	do {
617		if (ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) {
618			ac97c_writel(chip, COTHR, word);
619			return;
620		}
621		udelay(1);
622	} while (--timeout);
623
624	dev_dbg(&chip->pdev->dev, "codec write timeout\n");
625}
626
627static unsigned short atmel_ac97c_read(struct snd_ac97 *ac97,
628		unsigned short reg)
629{
630	struct atmel_ac97c *chip = get_chip(ac97);
631	unsigned long word;
632	int timeout = 40;
633	int write = 10;
634
635	word = (0x80 | (reg & 0x7f)) << 16;
636
637	if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0)
638		ac97c_readl(chip, CORHR);
639
640retry_write:
641	timeout = 40;
642
643	do {
644		if ((ac97c_readl(chip, COSR) & AC97C_CSR_TXRDY) != 0) {
645			ac97c_writel(chip, COTHR, word);
646			goto read_reg;
647		}
648		udelay(10);
649	} while (--timeout);
650
651	if (!--write)
652		goto timed_out;
653	goto retry_write;
654
655read_reg:
656	do {
657		if ((ac97c_readl(chip, COSR) & AC97C_CSR_RXRDY) != 0) {
658			unsigned short val = ac97c_readl(chip, CORHR);
659			return val;
660		}
661		udelay(10);
662	} while (--timeout);
663
664	if (!--write)
665		goto timed_out;
666	goto retry_write;
667
668timed_out:
669	dev_dbg(&chip->pdev->dev, "codec read timeout\n");
670	return 0xffff;
671}
672
673static void atmel_ac97c_reset(struct atmel_ac97c *chip)
674{
675	ac97c_writel(chip, MR,   0);
676	ac97c_writel(chip, MR,   AC97C_MR_ENA);
677	ac97c_writel(chip, CAMR, 0);
678	ac97c_writel(chip, COMR, 0);
679
680	if (!IS_ERR(chip->reset_pin)) {
681		gpiod_set_value(chip->reset_pin, 0);
682		/* AC97 v2.2 specifications says minimum 1 us. */
683		udelay(2);
684		gpiod_set_value(chip->reset_pin, 1);
685	} else {
686		ac97c_writel(chip, MR, AC97C_MR_WRST | AC97C_MR_ENA);
687		udelay(2);
688		ac97c_writel(chip, MR, AC97C_MR_ENA);
689	}
690}
691
692static const struct of_device_id atmel_ac97c_dt_ids[] = {
693	{ .compatible = "atmel,at91sam9263-ac97c", },
694	{ }
695};
696MODULE_DEVICE_TABLE(of, atmel_ac97c_dt_ids);
697
698static int atmel_ac97c_probe(struct platform_device *pdev)
699{
700	struct device			*dev = &pdev->dev;
701	struct snd_card			*card;
702	struct atmel_ac97c		*chip;
703	struct resource			*regs;
704	struct clk			*pclk;
705	static const struct snd_ac97_bus_ops	ops = {
706		.write	= atmel_ac97c_write,
707		.read	= atmel_ac97c_read,
708	};
709	int				retval;
710	int				irq;
711
712	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
713	if (!regs) {
714		dev_dbg(&pdev->dev, "no memory resource\n");
715		return -ENXIO;
716	}
717
718	irq = platform_get_irq(pdev, 0);
719	if (irq < 0) {
720		dev_dbg(&pdev->dev, "could not get irq: %d\n", irq);
721		return irq;
722	}
723
724	pclk = clk_get(&pdev->dev, "ac97_clk");
725	if (IS_ERR(pclk)) {
726		dev_dbg(&pdev->dev, "no peripheral clock\n");
727		return PTR_ERR(pclk);
728	}
729	retval = clk_prepare_enable(pclk);
730	if (retval)
731		goto err_prepare_enable;
732
733	retval = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1,
734			      SNDRV_DEFAULT_STR1, THIS_MODULE,
735			      sizeof(struct atmel_ac97c), &card);
736	if (retval) {
737		dev_dbg(&pdev->dev, "could not create sound card device\n");
738		goto err_snd_card_new;
739	}
740
741	chip = get_chip(card);
742
743	retval = request_irq(irq, atmel_ac97c_interrupt, 0, "AC97C", chip);
744	if (retval) {
745		dev_dbg(&pdev->dev, "unable to request irq %d\n", irq);
746		goto err_request_irq;
747	}
748	chip->irq = irq;
749
750	spin_lock_init(&chip->lock);
751
752	strcpy(card->driver, "Atmel AC97C");
753	strcpy(card->shortname, "Atmel AC97C");
754	sprintf(card->longname, "Atmel AC97 controller");
755
756	chip->card = card;
757	chip->pclk = pclk;
758	chip->pdev = pdev;
759	chip->regs = ioremap(regs->start, resource_size(regs));
760
761	if (!chip->regs) {
762		dev_dbg(&pdev->dev, "could not remap register memory\n");
763		retval = -ENOMEM;
764		goto err_ioremap;
765	}
766
767	chip->reset_pin = devm_gpiod_get_index(dev, "ac97", 2, GPIOD_OUT_HIGH);
768	if (IS_ERR(chip->reset_pin))
769		dev_dbg(dev, "reset pin not available\n");
770
771	atmel_ac97c_reset(chip);
772
773	/* Enable overrun interrupt from codec channel */
774	ac97c_writel(chip, COMR, AC97C_CSR_OVRUN);
775	ac97c_writel(chip, IER, ac97c_readl(chip, IMR) | AC97C_SR_COEVT);
776
777	retval = snd_ac97_bus(card, 0, &ops, chip, &chip->ac97_bus);
778	if (retval) {
779		dev_dbg(&pdev->dev, "could not register on ac97 bus\n");
780		goto err_ac97_bus;
781	}
782
783	retval = atmel_ac97c_mixer_new(chip);
784	if (retval) {
785		dev_dbg(&pdev->dev, "could not register ac97 mixer\n");
786		goto err_ac97_bus;
787	}
788
789	retval = atmel_ac97c_pcm_new(chip);
790	if (retval) {
791		dev_dbg(&pdev->dev, "could not register ac97 pcm device\n");
792		goto err_ac97_bus;
793	}
794
795	retval = snd_card_register(card);
796	if (retval) {
797		dev_dbg(&pdev->dev, "could not register sound card\n");
798		goto err_ac97_bus;
799	}
800
801	platform_set_drvdata(pdev, card);
802
803	dev_info(&pdev->dev, "Atmel AC97 controller at 0x%p, irq = %d\n",
804			chip->regs, irq);
805
806	return 0;
807
808err_ac97_bus:
809	iounmap(chip->regs);
810err_ioremap:
811	free_irq(irq, chip);
812err_request_irq:
813	snd_card_free(card);
814err_snd_card_new:
815	clk_disable_unprepare(pclk);
816err_prepare_enable:
817	clk_put(pclk);
818	return retval;
819}
820
821#ifdef CONFIG_PM_SLEEP
822static int atmel_ac97c_suspend(struct device *pdev)
823{
824	struct snd_card *card = dev_get_drvdata(pdev);
825	struct atmel_ac97c *chip = card->private_data;
826
827	clk_disable_unprepare(chip->pclk);
828	return 0;
829}
830
831static int atmel_ac97c_resume(struct device *pdev)
832{
833	struct snd_card *card = dev_get_drvdata(pdev);
834	struct atmel_ac97c *chip = card->private_data;
835	int ret = clk_prepare_enable(chip->pclk);
836
837	return ret;
838}
839
840static SIMPLE_DEV_PM_OPS(atmel_ac97c_pm, atmel_ac97c_suspend, atmel_ac97c_resume);
841#define ATMEL_AC97C_PM_OPS	&atmel_ac97c_pm
842#else
843#define ATMEL_AC97C_PM_OPS	NULL
844#endif
845
846static int atmel_ac97c_remove(struct platform_device *pdev)
847{
848	struct snd_card *card = platform_get_drvdata(pdev);
849	struct atmel_ac97c *chip = get_chip(card);
850
851	ac97c_writel(chip, CAMR, 0);
852	ac97c_writel(chip, COMR, 0);
853	ac97c_writel(chip, MR,   0);
854
855	clk_disable_unprepare(chip->pclk);
856	clk_put(chip->pclk);
857	iounmap(chip->regs);
858	free_irq(chip->irq, chip);
859
860	snd_card_free(card);
861
862	return 0;
863}
864
865static struct platform_driver atmel_ac97c_driver = {
866	.probe		= atmel_ac97c_probe,
867	.remove		= atmel_ac97c_remove,
868	.driver		= {
869		.name	= "atmel_ac97c",
870		.pm	= ATMEL_AC97C_PM_OPS,
871		.of_match_table = atmel_ac97c_dt_ids,
872	},
873};
874module_platform_driver(atmel_ac97c_driver);
875
876MODULE_LICENSE("GPL");
877MODULE_DESCRIPTION("Driver for Atmel AC97 controller");
878MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
879