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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Driver for Atmel I2S controller4 *5 * Copyright (C) 2015 Atmel Corporation6 *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	827 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_RXRDY146#define ATMEL_I2SC_INT_RXOR	ATMEL_I2SC_SR_RXOR147#define ATMEL_I2SC_INT_TXRDY	ATMEL_I2SC_SR_TXRDY148#define ATMEL_I2SC_INT_TXUR	ATMEL_I2SC_SR_TXUR149 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		12288000UL165#define I2S_MCK_11M2896		11289600UL166#define I2S_MCK_6M144		6144000UL167 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_192000254 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 start284			 * 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 Clock305	 * 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	else336		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		else373			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		= 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