1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Driver for Atmel I2S controller
4 *
5 * Copyright (C) 2015 Atmel Corporation
6 *
7 * Author: Cyrille Pitchen <cyrille.pitchen@atmel.com>
8 */
9
10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/device.h>
13#include <linux/slab.h>
14#include <linux/delay.h>
15#include <linux/io.h>
16#include <linux/clk.h>
17#include <linux/mfd/syscon.h>
18
19#include <sound/core.h>
20#include <sound/pcm.h>
21#include <sound/pcm_params.h>
22#include <sound/initval.h>
23#include <sound/soc.h>
24#include <sound/dmaengine_pcm.h>
25
26#define ATMEL_I2SC_MAX_TDM_CHANNELS	8
27
28/*
29 * ---- I2S Controller Register map ----
30 */
31#define ATMEL_I2SC_CR		0x0000	/* Control Register */
32#define ATMEL_I2SC_MR		0x0004	/* Mode Register */
33#define ATMEL_I2SC_SR		0x0008	/* Status Register */
34#define ATMEL_I2SC_SCR		0x000c	/* Status Clear Register */
35#define ATMEL_I2SC_SSR		0x0010	/* Status Set Register */
36#define ATMEL_I2SC_IER		0x0014	/* Interrupt Enable Register */
37#define ATMEL_I2SC_IDR		0x0018	/* Interrupt Disable Register */
38#define ATMEL_I2SC_IMR		0x001c	/* Interrupt Mask Register */
39#define ATMEL_I2SC_RHR		0x0020	/* Receiver Holding Register */
40#define ATMEL_I2SC_THR		0x0024	/* Transmitter Holding Register */
41#define ATMEL_I2SC_VERSION	0x0028	/* Version Register */
42
43/*
44 * ---- Control Register (Write-only) ----
45 */
46#define ATMEL_I2SC_CR_RXEN	BIT(0)	/* Receiver Enable */
47#define ATMEL_I2SC_CR_RXDIS	BIT(1)	/* Receiver Disable */
48#define ATMEL_I2SC_CR_CKEN	BIT(2)	/* Clock Enable */
49#define ATMEL_I2SC_CR_CKDIS	BIT(3)	/* Clock Disable */
50#define ATMEL_I2SC_CR_TXEN	BIT(4)	/* Transmitter Enable */
51#define ATMEL_I2SC_CR_TXDIS	BIT(5)	/* Transmitter Disable */
52#define ATMEL_I2SC_CR_SWRST	BIT(7)	/* Software Reset */
53
54/*
55 * ---- Mode Register (Read/Write) ----
56 */
57#define ATMEL_I2SC_MR_MODE_MASK		GENMASK(0, 0)
58#define ATMEL_I2SC_MR_MODE_SLAVE	(0 << 0)
59#define ATMEL_I2SC_MR_MODE_MASTER	(1 << 0)
60
61#define ATMEL_I2SC_MR_DATALENGTH_MASK		GENMASK(4, 2)
62#define ATMEL_I2SC_MR_DATALENGTH_32_BITS	(0 << 2)
63#define ATMEL_I2SC_MR_DATALENGTH_24_BITS	(1 << 2)
64#define ATMEL_I2SC_MR_DATALENGTH_20_BITS	(2 << 2)
65#define ATMEL_I2SC_MR_DATALENGTH_18_BITS	(3 << 2)
66#define ATMEL_I2SC_MR_DATALENGTH_16_BITS	(4 << 2)
67#define ATMEL_I2SC_MR_DATALENGTH_16_BITS_COMPACT	(5 << 2)
68#define ATMEL_I2SC_MR_DATALENGTH_8_BITS		(6 << 2)
69#define ATMEL_I2SC_MR_DATALENGTH_8_BITS_COMPACT	(7 << 2)
70
71#define ATMEL_I2SC_MR_FORMAT_MASK	GENMASK(7, 6)
72#define ATMEL_I2SC_MR_FORMAT_I2S	(0 << 6)
73#define ATMEL_I2SC_MR_FORMAT_LJ		(1 << 6)  /* Left Justified */
74#define ATMEL_I2SC_MR_FORMAT_TDM	(2 << 6)
75#define ATMEL_I2SC_MR_FORMAT_TDMLJ	(3 << 6)
76
77/* Left audio samples duplicated to right audio channel */
78#define ATMEL_I2SC_MR_RXMONO		BIT(8)
79
80/* Receiver uses one DMA channel ... */
81#define ATMEL_I2SC_MR_RXDMA_MASK	GENMASK(9, 9)
82#define ATMEL_I2SC_MR_RXDMA_SINGLE	(0 << 9)  /* for all audio channels */
83#define ATMEL_I2SC_MR_RXDMA_MULTIPLE	(1 << 9)  /* per audio channel */
84
85/* I2SDO output of I2SC is internally connected to I2SDI input */
86#define ATMEL_I2SC_MR_RXLOOP		BIT(10)
87
88/* Left audio samples duplicated to right audio channel */
89#define ATMEL_I2SC_MR_TXMONO		BIT(12)
90
91/* Transmitter uses one DMA channel ... */
92#define ATMEL_I2SC_MR_TXDMA_MASK	GENMASK(13, 13)
93#define ATMEL_I2SC_MR_TXDMA_SINGLE	(0 << 13)  /* for all audio channels */
94#define ATMEL_I2SC_MR_TXDME_MULTIPLE	(1 << 13)  /* per audio channel */
95
96/* x sample transmitted when underrun */
97#define ATMEL_I2SC_MR_TXSAME_MASK	GENMASK(14, 14)
98#define ATMEL_I2SC_MR_TXSAME_ZERO	(0 << 14)  /* Zero sample */
99#define ATMEL_I2SC_MR_TXSAME_PREVIOUS	(1 << 14)  /* Previous sample */
100
101/* Audio Clock to I2SC Master Clock ratio */
102#define ATMEL_I2SC_MR_IMCKDIV_MASK	GENMASK(21, 16)
103#define ATMEL_I2SC_MR_IMCKDIV(div) \
104	(((div) << 16) & ATMEL_I2SC_MR_IMCKDIV_MASK)
105
106/* Master Clock to fs ratio */
107#define ATMEL_I2SC_MR_IMCKFS_MASK	GENMASK(29, 24)
108#define ATMEL_I2SC_MR_IMCKFS(fs) \
109	(((fs) << 24) & ATMEL_I2SC_MR_IMCKFS_MASK)
110
111/* Master Clock mode */
112#define ATMEL_I2SC_MR_IMCKMODE_MASK	GENMASK(30, 30)
113/* 0: No master clock generated (selected clock drives I2SCK pin) */
114#define ATMEL_I2SC_MR_IMCKMODE_I2SCK	(0 << 30)
115/* 1: master clock generated (internally generated clock drives I2SMCK pin) */
116#define ATMEL_I2SC_MR_IMCKMODE_I2SMCK	(1 << 30)
117
118/* Slot Width */
119/* 0: slot is 32 bits wide for DATALENGTH = 18/20/24 bits. */
120/* 1: slot is 24 bits wide for DATALENGTH = 18/20/24 bits. */
121#define ATMEL_I2SC_MR_IWS		BIT(31)
122
123/*
124 * ---- Status Registers ----
125 */
126#define ATMEL_I2SC_SR_RXEN	BIT(0)	/* Receiver Enabled */
127#define ATMEL_I2SC_SR_RXRDY	BIT(1)	/* Receive Ready */
128#define ATMEL_I2SC_SR_RXOR	BIT(2)	/* Receive Overrun */
129
130#define ATMEL_I2SC_SR_TXEN	BIT(4)	/* Transmitter Enabled */
131#define ATMEL_I2SC_SR_TXRDY	BIT(5)	/* Transmit Ready */
132#define ATMEL_I2SC_SR_TXUR	BIT(6)	/* Transmit Underrun */
133
134/* Receive Overrun Channel */
135#define ATMEL_I2SC_SR_RXORCH_MASK	GENMASK(15, 8)
136#define ATMEL_I2SC_SR_RXORCH(ch)	(1 << (((ch) & 0x7) + 8))
137
138/* Transmit Underrun Channel */
139#define ATMEL_I2SC_SR_TXURCH_MASK	GENMASK(27, 20)
140#define ATMEL_I2SC_SR_TXURCH(ch)	(1 << (((ch) & 0x7) + 20))
141
142/*
143 * ---- Interrupt Enable/Disable/Mask Registers ----
144 */
145#define ATMEL_I2SC_INT_RXRDY	ATMEL_I2SC_SR_RXRDY
146#define ATMEL_I2SC_INT_RXOR	ATMEL_I2SC_SR_RXOR
147#define ATMEL_I2SC_INT_TXRDY	ATMEL_I2SC_SR_TXRDY
148#define ATMEL_I2SC_INT_TXUR	ATMEL_I2SC_SR_TXUR
149
150static const struct regmap_config atmel_i2s_regmap_config = {
151	.reg_bits = 32,
152	.reg_stride = 4,
153	.val_bits = 32,
154	.max_register = ATMEL_I2SC_VERSION,
155};
156
157struct atmel_i2s_gck_param {
158	int		fs;
159	unsigned long	mck;
160	int		imckdiv;
161	int		imckfs;
162};
163
164#define I2S_MCK_12M288		12288000UL
165#define I2S_MCK_11M2896		11289600UL
166#define I2S_MCK_6M144		6144000UL
167
168/* mck = (32 * (imckfs+1) / (imckdiv+1)) * fs */
169static const struct atmel_i2s_gck_param gck_params[] = {
170	/* mck = 6.144Mhz */
171	{  8000, I2S_MCK_6M144,  1, 47},	/* mck =  768 fs */
172
173	/* mck = 12.288MHz */
174	{ 16000, I2S_MCK_12M288, 1, 47},	/* mck =  768 fs */
175	{ 24000, I2S_MCK_12M288, 3, 63},	/* mck =  512 fs */
176	{ 32000, I2S_MCK_12M288, 3, 47},	/* mck =  384 fs */
177	{ 48000, I2S_MCK_12M288, 7, 63},	/* mck =  256 fs */
178	{ 64000, I2S_MCK_12M288, 7, 47},	/* mck =  192 fs */
179	{ 96000, I2S_MCK_12M288, 7, 31},	/* mck =  128 fs */
180	{192000, I2S_MCK_12M288, 7, 15},	/* mck =   64 fs */
181
182	/* mck = 11.2896MHz */
183	{ 11025, I2S_MCK_11M2896, 1, 63},	/* mck = 1024 fs */
184	{ 22050, I2S_MCK_11M2896, 3, 63},	/* mck =  512 fs */
185	{ 44100, I2S_MCK_11M2896, 7, 63},	/* mck =  256 fs */
186	{ 88200, I2S_MCK_11M2896, 7, 31},	/* mck =  128 fs */
187	{176400, I2S_MCK_11M2896, 7, 15},	/* mck =   64 fs */
188};
189
190struct atmel_i2s_dev;
191
192struct atmel_i2s_caps {
193	int	(*mck_init)(struct atmel_i2s_dev *, struct device_node *np);
194};
195
196struct atmel_i2s_dev {
197	struct device				*dev;
198	struct regmap				*regmap;
199	struct clk				*pclk;
200	struct clk				*gclk;
201	struct snd_dmaengine_dai_dma_data	playback;
202	struct snd_dmaengine_dai_dma_data	capture;
203	unsigned int				fmt;
204	const struct atmel_i2s_gck_param	*gck_param;
205	const struct atmel_i2s_caps		*caps;
206	int					clk_use_no;
207};
208
209static irqreturn_t atmel_i2s_interrupt(int irq, void *dev_id)
210{
211	struct atmel_i2s_dev *dev = dev_id;
212	unsigned int sr, imr, pending, ch, mask;
213	irqreturn_t ret = IRQ_NONE;
214
215	regmap_read(dev->regmap, ATMEL_I2SC_SR, &sr);
216	regmap_read(dev->regmap, ATMEL_I2SC_IMR, &imr);
217	pending = sr & imr;
218
219	if (!pending)
220		return IRQ_NONE;
221
222	if (pending & ATMEL_I2SC_INT_RXOR) {
223		mask = ATMEL_I2SC_SR_RXOR;
224
225		for (ch = 0; ch < ATMEL_I2SC_MAX_TDM_CHANNELS; ++ch) {
226			if (sr & ATMEL_I2SC_SR_RXORCH(ch)) {
227				mask |= ATMEL_I2SC_SR_RXORCH(ch);
228				dev_err(dev->dev,
229					"RX overrun on channel %d\n", ch);
230			}
231		}
232		regmap_write(dev->regmap, ATMEL_I2SC_SCR, mask);
233		ret = IRQ_HANDLED;
234	}
235
236	if (pending & ATMEL_I2SC_INT_TXUR) {
237		mask = ATMEL_I2SC_SR_TXUR;
238
239		for (ch = 0; ch < ATMEL_I2SC_MAX_TDM_CHANNELS; ++ch) {
240			if (sr & ATMEL_I2SC_SR_TXURCH(ch)) {
241				mask |= ATMEL_I2SC_SR_TXURCH(ch);
242				dev_err(dev->dev,
243					"TX underrun on channel %d\n", ch);
244			}
245		}
246		regmap_write(dev->regmap, ATMEL_I2SC_SCR, mask);
247		ret = IRQ_HANDLED;
248	}
249
250	return ret;
251}
252
253#define ATMEL_I2S_RATES		SNDRV_PCM_RATE_8000_192000
254
255#define ATMEL_I2S_FORMATS	(SNDRV_PCM_FMTBIT_S8 |		\
256				 SNDRV_PCM_FMTBIT_S16_LE |	\
257				 SNDRV_PCM_FMTBIT_S18_3LE |	\
258				 SNDRV_PCM_FMTBIT_S20_3LE |	\
259				 SNDRV_PCM_FMTBIT_S24_3LE |	\
260				 SNDRV_PCM_FMTBIT_S24_LE |	\
261				 SNDRV_PCM_FMTBIT_S32_LE)
262
263static int atmel_i2s_set_dai_fmt(struct snd_soc_dai *dai, unsigned int fmt)
264{
265	struct atmel_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
266
267	dev->fmt = fmt;
268	return 0;
269}
270
271static int atmel_i2s_prepare(struct snd_pcm_substream *substream,
272			     struct snd_soc_dai *dai)
273{
274	struct atmel_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
275	bool is_playback = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
276	unsigned int rhr, sr = 0;
277
278	if (is_playback) {
279		regmap_read(dev->regmap, ATMEL_I2SC_SR, &sr);
280		if (sr & ATMEL_I2SC_SR_RXRDY) {
281			/*
282			 * The RX Ready flag should not be set. However if here,
283			 * we flush (read) the Receive Holding Register to start
284			 * from a clean state.
285			 */
286			dev_dbg(dev->dev, "RXRDY is set\n");
287			regmap_read(dev->regmap, ATMEL_I2SC_RHR, &rhr);
288		}
289	}
290
291	return 0;
292}
293
294static int atmel_i2s_get_gck_param(struct atmel_i2s_dev *dev, int fs)
295{
296	int i, best;
297
298	if (!dev->gclk) {
299		dev_err(dev->dev, "cannot generate the I2S Master Clock\n");
300		return -EINVAL;
301	}
302
303	/*
304	 * Find the best possible settings to generate the I2S Master Clock
305	 * from the PLL Audio.
306	 */
307	dev->gck_param = NULL;
308	best = INT_MAX;
309	for (i = 0; i < ARRAY_SIZE(gck_params); ++i) {
310		const struct atmel_i2s_gck_param *gck_param = &gck_params[i];
311		int val = abs(fs - gck_param->fs);
312
313		if (val < best) {
314			best = val;
315			dev->gck_param = gck_param;
316		}
317	}
318
319	return 0;
320}
321
322static int atmel_i2s_hw_params(struct snd_pcm_substream *substream,
323			       struct snd_pcm_hw_params *params,
324			       struct snd_soc_dai *dai)
325{
326	struct atmel_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
327	bool is_playback = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
328	unsigned int mr = 0, mr_mask;
329	int ret;
330
331	mr_mask = ATMEL_I2SC_MR_FORMAT_MASK | ATMEL_I2SC_MR_MODE_MASK |
332		ATMEL_I2SC_MR_DATALENGTH_MASK;
333	if (is_playback)
334		mr_mask |= ATMEL_I2SC_MR_TXMONO;
335	else
336		mr_mask |= ATMEL_I2SC_MR_RXMONO;
337
338	switch (dev->fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
339	case SND_SOC_DAIFMT_I2S:
340		mr |= ATMEL_I2SC_MR_FORMAT_I2S;
341		break;
342
343	default:
344		dev_err(dev->dev, "unsupported bus format\n");
345		return -EINVAL;
346	}
347
348	switch (dev->fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
349	case SND_SOC_DAIFMT_BP_FP:
350		/* codec is slave, so cpu is master */
351		mr |= ATMEL_I2SC_MR_MODE_MASTER;
352		ret = atmel_i2s_get_gck_param(dev, params_rate(params));
353		if (ret)
354			return ret;
355		break;
356
357	case SND_SOC_DAIFMT_BC_FC:
358		/* codec is master, so cpu is slave */
359		mr |= ATMEL_I2SC_MR_MODE_SLAVE;
360		dev->gck_param = NULL;
361		break;
362
363	default:
364		dev_err(dev->dev, "unsupported master/slave mode\n");
365		return -EINVAL;
366	}
367
368	switch (params_channels(params)) {
369	case 1:
370		if (is_playback)
371			mr |= ATMEL_I2SC_MR_TXMONO;
372		else
373			mr |= ATMEL_I2SC_MR_RXMONO;
374		break;
375	case 2:
376		break;
377	default:
378		dev_err(dev->dev, "unsupported number of audio channels\n");
379		return -EINVAL;
380	}
381
382	switch (params_format(params)) {
383	case SNDRV_PCM_FORMAT_S8:
384		mr |= ATMEL_I2SC_MR_DATALENGTH_8_BITS;
385		break;
386
387	case SNDRV_PCM_FORMAT_S16_LE:
388		mr |= ATMEL_I2SC_MR_DATALENGTH_16_BITS;
389		break;
390
391	case SNDRV_PCM_FORMAT_S18_3LE:
392		mr |= ATMEL_I2SC_MR_DATALENGTH_18_BITS | ATMEL_I2SC_MR_IWS;
393		break;
394
395	case SNDRV_PCM_FORMAT_S20_3LE:
396		mr |= ATMEL_I2SC_MR_DATALENGTH_20_BITS | ATMEL_I2SC_MR_IWS;
397		break;
398
399	case SNDRV_PCM_FORMAT_S24_3LE:
400		mr |= ATMEL_I2SC_MR_DATALENGTH_24_BITS | ATMEL_I2SC_MR_IWS;
401		break;
402
403	case SNDRV_PCM_FORMAT_S24_LE:
404		mr |= ATMEL_I2SC_MR_DATALENGTH_24_BITS;
405		break;
406
407	case SNDRV_PCM_FORMAT_S32_LE:
408		mr |= ATMEL_I2SC_MR_DATALENGTH_32_BITS;
409		break;
410
411	default:
412		dev_err(dev->dev, "unsupported size/endianness for audio samples\n");
413		return -EINVAL;
414	}
415
416	return regmap_update_bits(dev->regmap, ATMEL_I2SC_MR, mr_mask, mr);
417}
418
419static int atmel_i2s_switch_mck_generator(struct atmel_i2s_dev *dev,
420					  bool enabled)
421{
422	unsigned int mr, mr_mask;
423	unsigned long gclk_rate;
424	int ret;
425
426	mr = 0;
427	mr_mask = (ATMEL_I2SC_MR_IMCKDIV_MASK |
428		   ATMEL_I2SC_MR_IMCKFS_MASK |
429		   ATMEL_I2SC_MR_IMCKMODE_MASK);
430
431	if (!enabled) {
432		/* Disable the I2S Master Clock generator. */
433		ret = regmap_write(dev->regmap, ATMEL_I2SC_CR,
434				   ATMEL_I2SC_CR_CKDIS);
435		if (ret)
436			return ret;
437
438		/* Reset the I2S Master Clock generator settings. */
439		ret = regmap_update_bits(dev->regmap, ATMEL_I2SC_MR,
440					 mr_mask, mr);
441		if (ret)
442			return ret;
443
444		/* Disable/unprepare the PMC generated clock. */
445		clk_disable_unprepare(dev->gclk);
446
447		return 0;
448	}
449
450	if (!dev->gck_param)
451		return -EINVAL;
452
453	gclk_rate = dev->gck_param->mck * (dev->gck_param->imckdiv + 1);
454
455	ret = clk_set_rate(dev->gclk, gclk_rate);
456	if (ret)
457		return ret;
458
459	ret = clk_prepare_enable(dev->gclk);
460	if (ret)
461		return ret;
462
463	/* Update the Mode Register to generate the I2S Master Clock. */
464	mr |= ATMEL_I2SC_MR_IMCKDIV(dev->gck_param->imckdiv);
465	mr |= ATMEL_I2SC_MR_IMCKFS(dev->gck_param->imckfs);
466	mr |= ATMEL_I2SC_MR_IMCKMODE_I2SMCK;
467	ret = regmap_update_bits(dev->regmap, ATMEL_I2SC_MR, mr_mask, mr);
468	if (ret)
469		return ret;
470
471	/* Finally enable the I2S Master Clock generator. */
472	return regmap_write(dev->regmap, ATMEL_I2SC_CR,
473			    ATMEL_I2SC_CR_CKEN);
474}
475
476static int atmel_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
477			     struct snd_soc_dai *dai)
478{
479	struct atmel_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
480	bool is_playback = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
481	bool is_master, mck_enabled;
482	unsigned int cr, mr;
483	int err;
484
485	switch (cmd) {
486	case SNDRV_PCM_TRIGGER_START:
487	case SNDRV_PCM_TRIGGER_RESUME:
488	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
489		cr = is_playback ? ATMEL_I2SC_CR_TXEN : ATMEL_I2SC_CR_RXEN;
490		mck_enabled = true;
491		break;
492	case SNDRV_PCM_TRIGGER_STOP:
493	case SNDRV_PCM_TRIGGER_SUSPEND:
494	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
495		cr = is_playback ? ATMEL_I2SC_CR_TXDIS : ATMEL_I2SC_CR_RXDIS;
496		mck_enabled = false;
497		break;
498	default:
499		return -EINVAL;
500	}
501
502	/* Read the Mode Register to retrieve the master/slave state. */
503	err = regmap_read(dev->regmap, ATMEL_I2SC_MR, &mr);
504	if (err)
505		return err;
506	is_master = (mr & ATMEL_I2SC_MR_MODE_MASK) == ATMEL_I2SC_MR_MODE_MASTER;
507
508	/* If master starts, enable the audio clock. */
509	if (is_master && mck_enabled) {
510		if (!dev->clk_use_no) {
511			err = atmel_i2s_switch_mck_generator(dev, true);
512			if (err)
513				return err;
514		}
515		dev->clk_use_no++;
516	}
517
518	err = regmap_write(dev->regmap, ATMEL_I2SC_CR, cr);
519	if (err)
520		return err;
521
522	/* If master stops, disable the audio clock. */
523	if (is_master && !mck_enabled) {
524		if (dev->clk_use_no == 1) {
525			err = atmel_i2s_switch_mck_generator(dev, false);
526			if (err)
527				return err;
528		}
529		dev->clk_use_no--;
530	}
531
532	return err;
533}
534
535static int atmel_i2s_dai_probe(struct snd_soc_dai *dai)
536{
537	struct atmel_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
538
539	snd_soc_dai_init_dma_data(dai, &dev->playback, &dev->capture);
540	return 0;
541}
542
543static const struct snd_soc_dai_ops atmel_i2s_dai_ops = {
544	.probe		= atmel_i2s_dai_probe,
545	.prepare	= atmel_i2s_prepare,
546	.trigger	= atmel_i2s_trigger,
547	.hw_params	= atmel_i2s_hw_params,
548	.set_fmt	= atmel_i2s_set_dai_fmt,
549};
550
551static struct snd_soc_dai_driver atmel_i2s_dai = {
552	.playback = {
553		.channels_min = 1,
554		.channels_max = 2,
555		.rates = ATMEL_I2S_RATES,
556		.formats = ATMEL_I2S_FORMATS,
557	},
558	.capture = {
559		.channels_min = 1,
560		.channels_max = 2,
561		.rates = ATMEL_I2S_RATES,
562		.formats = ATMEL_I2S_FORMATS,
563	},
564	.ops = &atmel_i2s_dai_ops,
565	.symmetric_rate = 1,
566	.symmetric_sample_bits = 1,
567};
568
569static const struct snd_soc_component_driver atmel_i2s_component = {
570	.name			= "atmel-i2s",
571	.legacy_dai_naming	= 1,
572};
573
574static int atmel_i2s_sama5d2_mck_init(struct atmel_i2s_dev *dev,
575				      struct device_node *np)
576{
577	struct clk *muxclk;
578	int err;
579
580	if (!dev->gclk)
581		return 0;
582
583	/* muxclk is optional, so we return error for probe defer only */
584	muxclk = devm_clk_get(dev->dev, "muxclk");
585	if (IS_ERR(muxclk)) {
586		err = PTR_ERR(muxclk);
587		if (err == -EPROBE_DEFER)
588			return -EPROBE_DEFER;
589		dev_dbg(dev->dev,
590			"failed to get the I2S clock control: %d\n", err);
591		return 0;
592	}
593
594	return clk_set_parent(muxclk, dev->gclk);
595}
596
597static const struct atmel_i2s_caps atmel_i2s_sama5d2_caps = {
598	.mck_init = atmel_i2s_sama5d2_mck_init,
599};
600
601static const struct of_device_id atmel_i2s_dt_ids[] = {
602	{
603		.compatible = "atmel,sama5d2-i2s",
604		.data = (void *)&atmel_i2s_sama5d2_caps,
605	},
606
607	{ /* sentinel */ }
608};
609
610MODULE_DEVICE_TABLE(of, atmel_i2s_dt_ids);
611
612static int atmel_i2s_probe(struct platform_device *pdev)
613{
614	struct device_node *np = pdev->dev.of_node;
615	const struct of_device_id *match;
616	struct atmel_i2s_dev *dev;
617	struct resource *mem;
618	struct regmap *regmap;
619	void __iomem *base;
620	int irq;
621	int err;
622	unsigned int pcm_flags = 0;
623	unsigned int version;
624
625	/* Get memory for driver data. */
626	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
627	if (!dev)
628		return -ENOMEM;
629
630	/* Get hardware capabilities. */
631	match = of_match_node(atmel_i2s_dt_ids, np);
632	if (match)
633		dev->caps = match->data;
634
635	/* Map I/O registers. */
636	base = devm_platform_get_and_ioremap_resource(pdev, 0, &mem);
637	if (IS_ERR(base))
638		return PTR_ERR(base);
639
640	regmap = devm_regmap_init_mmio(&pdev->dev, base,
641				       &atmel_i2s_regmap_config);
642	if (IS_ERR(regmap))
643		return PTR_ERR(regmap);
644
645	/* Request IRQ. */
646	irq = platform_get_irq(pdev, 0);
647	if (irq < 0)
648		return irq;
649
650	err = devm_request_irq(&pdev->dev, irq, atmel_i2s_interrupt, 0,
651			       dev_name(&pdev->dev), dev);
652	if (err)
653		return err;
654
655	/* Get the peripheral clock. */
656	dev->pclk = devm_clk_get(&pdev->dev, "pclk");
657	if (IS_ERR(dev->pclk)) {
658		err = PTR_ERR(dev->pclk);
659		dev_err(&pdev->dev,
660			"failed to get the peripheral clock: %d\n", err);
661		return err;
662	}
663
664	/* Get audio clock to generate the I2S Master Clock (I2S_MCK) */
665	dev->gclk = devm_clk_get(&pdev->dev, "gclk");
666	if (IS_ERR(dev->gclk)) {
667		if (PTR_ERR(dev->gclk) == -EPROBE_DEFER)
668			return -EPROBE_DEFER;
669		/* Master Mode not supported */
670		dev->gclk = NULL;
671	}
672	dev->dev = &pdev->dev;
673	dev->regmap = regmap;
674	platform_set_drvdata(pdev, dev);
675
676	/* Do hardware specific settings to initialize I2S_MCK generator */
677	if (dev->caps && dev->caps->mck_init) {
678		err = dev->caps->mck_init(dev, np);
679		if (err)
680			return err;
681	}
682
683	/* Enable the peripheral clock. */
684	err = clk_prepare_enable(dev->pclk);
685	if (err)
686		return err;
687
688	/* Get IP version. */
689	regmap_read(dev->regmap, ATMEL_I2SC_VERSION, &version);
690	dev_info(&pdev->dev, "hw version: %#x\n", version);
691
692	/* Enable error interrupts. */
693	regmap_write(dev->regmap, ATMEL_I2SC_IER,
694		     ATMEL_I2SC_INT_RXOR | ATMEL_I2SC_INT_TXUR);
695
696	err = devm_snd_soc_register_component(&pdev->dev,
697					      &atmel_i2s_component,
698					      &atmel_i2s_dai, 1);
699	if (err) {
700		dev_err(&pdev->dev, "failed to register DAI: %d\n", err);
701		clk_disable_unprepare(dev->pclk);
702		return err;
703	}
704
705	/* Prepare DMA config. */
706	dev->playback.addr	= (dma_addr_t)mem->start + ATMEL_I2SC_THR;
707	dev->playback.maxburst	= 1;
708	dev->capture.addr	= (dma_addr_t)mem->start + ATMEL_I2SC_RHR;
709	dev->capture.maxburst	= 1;
710
711	if (of_property_match_string(np, "dma-names", "rx-tx") == 0)
712		pcm_flags |= SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX;
713	err = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, pcm_flags);
714	if (err) {
715		dev_err(&pdev->dev, "failed to register PCM: %d\n", err);
716		clk_disable_unprepare(dev->pclk);
717		return err;
718	}
719
720	return 0;
721}
722
723static void atmel_i2s_remove(struct platform_device *pdev)
724{
725	struct atmel_i2s_dev *dev = platform_get_drvdata(pdev);
726
727	clk_disable_unprepare(dev->pclk);
728}
729
730static struct platform_driver atmel_i2s_driver = {
731	.driver		= {
732		.name	= "atmel_i2s",
733		.of_match_table	= atmel_i2s_dt_ids,
734	},
735	.probe		= atmel_i2s_probe,
736	.remove_new	= atmel_i2s_remove,
737};
738module_platform_driver(atmel_i2s_driver);
739
740MODULE_DESCRIPTION("Atmel I2S Controller driver");
741MODULE_AUTHOR("Cyrille Pitchen <cyrille.pitchen@atmel.com>");
742MODULE_LICENSE("GPL v2");
743