// SPDX-License-Identifier: GPL-2.0-only /* * Driver for Atmel I2S controller * * Copyright (C) 2015 Atmel Corporation * * Author: Cyrille Pitchen */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define ATMEL_I2SC_MAX_TDM_CHANNELS 8 /* * ---- I2S Controller Register map ---- */ #define ATMEL_I2SC_CR 0x0000 /* Control Register */ #define ATMEL_I2SC_MR 0x0004 /* Mode Register */ #define ATMEL_I2SC_SR 0x0008 /* Status Register */ #define ATMEL_I2SC_SCR 0x000c /* Status Clear Register */ #define ATMEL_I2SC_SSR 0x0010 /* Status Set Register */ #define ATMEL_I2SC_IER 0x0014 /* Interrupt Enable Register */ #define ATMEL_I2SC_IDR 0x0018 /* Interrupt Disable Register */ #define ATMEL_I2SC_IMR 0x001c /* Interrupt Mask Register */ #define ATMEL_I2SC_RHR 0x0020 /* Receiver Holding Register */ #define ATMEL_I2SC_THR 0x0024 /* Transmitter Holding Register */ #define ATMEL_I2SC_VERSION 0x0028 /* Version Register */ /* * ---- Control Register (Write-only) ---- */ #define ATMEL_I2SC_CR_RXEN BIT(0) /* Receiver Enable */ #define ATMEL_I2SC_CR_RXDIS BIT(1) /* Receiver Disable */ #define ATMEL_I2SC_CR_CKEN BIT(2) /* Clock Enable */ #define ATMEL_I2SC_CR_CKDIS BIT(3) /* Clock Disable */ #define ATMEL_I2SC_CR_TXEN BIT(4) /* Transmitter Enable */ #define ATMEL_I2SC_CR_TXDIS BIT(5) /* Transmitter Disable */ #define ATMEL_I2SC_CR_SWRST BIT(7) /* Software Reset */ /* * ---- Mode Register (Read/Write) ---- */ #define ATMEL_I2SC_MR_MODE_MASK GENMASK(0, 0) #define ATMEL_I2SC_MR_MODE_SLAVE (0 << 0) #define ATMEL_I2SC_MR_MODE_MASTER (1 << 0) #define ATMEL_I2SC_MR_DATALENGTH_MASK GENMASK(4, 2) #define ATMEL_I2SC_MR_DATALENGTH_32_BITS (0 << 2) #define ATMEL_I2SC_MR_DATALENGTH_24_BITS (1 << 2) #define ATMEL_I2SC_MR_DATALENGTH_20_BITS (2 << 2) #define ATMEL_I2SC_MR_DATALENGTH_18_BITS (3 << 2) #define ATMEL_I2SC_MR_DATALENGTH_16_BITS (4 << 2) #define ATMEL_I2SC_MR_DATALENGTH_16_BITS_COMPACT (5 << 2) #define ATMEL_I2SC_MR_DATALENGTH_8_BITS (6 << 2) #define ATMEL_I2SC_MR_DATALENGTH_8_BITS_COMPACT (7 << 2) #define ATMEL_I2SC_MR_FORMAT_MASK GENMASK(7, 6) #define ATMEL_I2SC_MR_FORMAT_I2S (0 << 6) #define ATMEL_I2SC_MR_FORMAT_LJ (1 << 6) /* Left Justified */ #define ATMEL_I2SC_MR_FORMAT_TDM (2 << 6) #define ATMEL_I2SC_MR_FORMAT_TDMLJ (3 << 6) /* Left audio samples duplicated to right audio channel */ #define ATMEL_I2SC_MR_RXMONO BIT(8) /* Receiver uses one DMA channel ... */ #define ATMEL_I2SC_MR_RXDMA_MASK GENMASK(9, 9) #define ATMEL_I2SC_MR_RXDMA_SINGLE (0 << 9) /* for all audio channels */ #define ATMEL_I2SC_MR_RXDMA_MULTIPLE (1 << 9) /* per audio channel */ /* I2SDO output of I2SC is internally connected to I2SDI input */ #define ATMEL_I2SC_MR_RXLOOP BIT(10) /* Left audio samples duplicated to right audio channel */ #define ATMEL_I2SC_MR_TXMONO BIT(12) /* Transmitter uses one DMA channel ... */ #define ATMEL_I2SC_MR_TXDMA_MASK GENMASK(13, 13) #define ATMEL_I2SC_MR_TXDMA_SINGLE (0 << 13) /* for all audio channels */ #define ATMEL_I2SC_MR_TXDME_MULTIPLE (1 << 13) /* per audio channel */ /* x sample transmitted when underrun */ #define ATMEL_I2SC_MR_TXSAME_MASK GENMASK(14, 14) #define ATMEL_I2SC_MR_TXSAME_ZERO (0 << 14) /* Zero sample */ #define ATMEL_I2SC_MR_TXSAME_PREVIOUS (1 << 14) /* Previous sample */ /* Audio Clock to I2SC Master Clock ratio */ #define ATMEL_I2SC_MR_IMCKDIV_MASK GENMASK(21, 16) #define ATMEL_I2SC_MR_IMCKDIV(div) \ (((div) << 16) & ATMEL_I2SC_MR_IMCKDIV_MASK) /* Master Clock to fs ratio */ #define ATMEL_I2SC_MR_IMCKFS_MASK GENMASK(29, 24) #define ATMEL_I2SC_MR_IMCKFS(fs) \ (((fs) << 24) & ATMEL_I2SC_MR_IMCKFS_MASK) /* Master Clock mode */ #define ATMEL_I2SC_MR_IMCKMODE_MASK GENMASK(30, 30) /* 0: No master clock generated (selected clock drives I2SCK pin) */ #define ATMEL_I2SC_MR_IMCKMODE_I2SCK (0 << 30) /* 1: master clock generated (internally generated clock drives I2SMCK pin) */ #define ATMEL_I2SC_MR_IMCKMODE_I2SMCK (1 << 30) /* Slot Width */ /* 0: slot is 32 bits wide for DATALENGTH = 18/20/24 bits. */ /* 1: slot is 24 bits wide for DATALENGTH = 18/20/24 bits. */ #define ATMEL_I2SC_MR_IWS BIT(31) /* * ---- Status Registers ---- */ #define ATMEL_I2SC_SR_RXEN BIT(0) /* Receiver Enabled */ #define ATMEL_I2SC_SR_RXRDY BIT(1) /* Receive Ready */ #define ATMEL_I2SC_SR_RXOR BIT(2) /* Receive Overrun */ #define ATMEL_I2SC_SR_TXEN BIT(4) /* Transmitter Enabled */ #define ATMEL_I2SC_SR_TXRDY BIT(5) /* Transmit Ready */ #define ATMEL_I2SC_SR_TXUR BIT(6) /* Transmit Underrun */ /* Receive Overrun Channel */ #define ATMEL_I2SC_SR_RXORCH_MASK GENMASK(15, 8) #define ATMEL_I2SC_SR_RXORCH(ch) (1 << (((ch) & 0x7) + 8)) /* Transmit Underrun Channel */ #define ATMEL_I2SC_SR_TXURCH_MASK GENMASK(27, 20) #define ATMEL_I2SC_SR_TXURCH(ch) (1 << (((ch) & 0x7) + 20)) /* * ---- Interrupt Enable/Disable/Mask Registers ---- */ #define ATMEL_I2SC_INT_RXRDY ATMEL_I2SC_SR_RXRDY #define ATMEL_I2SC_INT_RXOR ATMEL_I2SC_SR_RXOR #define ATMEL_I2SC_INT_TXRDY ATMEL_I2SC_SR_TXRDY #define ATMEL_I2SC_INT_TXUR ATMEL_I2SC_SR_TXUR static const struct regmap_config atmel_i2s_regmap_config = { .reg_bits = 32, .reg_stride = 4, .val_bits = 32, .max_register = ATMEL_I2SC_VERSION, }; struct atmel_i2s_gck_param { int fs; unsigned long mck; int imckdiv; int imckfs; }; #define I2S_MCK_12M288 12288000UL #define I2S_MCK_11M2896 11289600UL /* mck = (32 * (imckfs+1) / (imckdiv+1)) * fs */ static const struct atmel_i2s_gck_param gck_params[] = { /* mck = 12.288MHz */ { 8000, I2S_MCK_12M288, 0, 47}, /* mck = 1536 fs */ { 16000, I2S_MCK_12M288, 1, 47}, /* mck = 768 fs */ { 24000, I2S_MCK_12M288, 3, 63}, /* mck = 512 fs */ { 32000, I2S_MCK_12M288, 3, 47}, /* mck = 384 fs */ { 48000, I2S_MCK_12M288, 7, 63}, /* mck = 256 fs */ { 64000, I2S_MCK_12M288, 7, 47}, /* mck = 192 fs */ { 96000, I2S_MCK_12M288, 7, 31}, /* mck = 128 fs */ {192000, I2S_MCK_12M288, 7, 15}, /* mck = 64 fs */ /* mck = 11.2896MHz */ { 11025, I2S_MCK_11M2896, 1, 63}, /* mck = 1024 fs */ { 22050, I2S_MCK_11M2896, 3, 63}, /* mck = 512 fs */ { 44100, I2S_MCK_11M2896, 7, 63}, /* mck = 256 fs */ { 88200, I2S_MCK_11M2896, 7, 31}, /* mck = 128 fs */ {176400, I2S_MCK_11M2896, 7, 15}, /* mck = 64 fs */ }; struct atmel_i2s_dev; struct atmel_i2s_caps { int (*mck_init)(struct atmel_i2s_dev *, struct device_node *np); }; struct atmel_i2s_dev { struct device *dev; struct regmap *regmap; struct clk *pclk; struct clk *gclk; struct snd_dmaengine_dai_dma_data playback; struct snd_dmaengine_dai_dma_data capture; unsigned int fmt; const struct atmel_i2s_gck_param *gck_param; const struct atmel_i2s_caps *caps; }; static irqreturn_t atmel_i2s_interrupt(int irq, void *dev_id) { struct atmel_i2s_dev *dev = dev_id; unsigned int sr, imr, pending, ch, mask; irqreturn_t ret = IRQ_NONE; regmap_read(dev->regmap, ATMEL_I2SC_SR, &sr); regmap_read(dev->regmap, ATMEL_I2SC_IMR, &imr); pending = sr & imr; if (!pending) return IRQ_NONE; if (pending & ATMEL_I2SC_INT_RXOR) { mask = ATMEL_I2SC_SR_RXOR; for (ch = 0; ch < ATMEL_I2SC_MAX_TDM_CHANNELS; ++ch) { if (sr & ATMEL_I2SC_SR_RXORCH(ch)) { mask |= ATMEL_I2SC_SR_RXORCH(ch); dev_err(dev->dev, "RX overrun on channel %d\n", ch); } } regmap_write(dev->regmap, ATMEL_I2SC_SCR, mask); ret = IRQ_HANDLED; } if (pending & ATMEL_I2SC_INT_TXUR) { mask = ATMEL_I2SC_SR_TXUR; for (ch = 0; ch < ATMEL_I2SC_MAX_TDM_CHANNELS; ++ch) { if (sr & ATMEL_I2SC_SR_TXURCH(ch)) { mask |= ATMEL_I2SC_SR_TXURCH(ch); dev_err(dev->dev, "TX underrun on channel %d\n", ch); } } regmap_write(dev->regmap, ATMEL_I2SC_SCR, mask); ret = IRQ_HANDLED; } return ret; } #define ATMEL_I2S_RATES SNDRV_PCM_RATE_8000_192000 #define ATMEL_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | \ SNDRV_PCM_FMTBIT_S16_LE | \ SNDRV_PCM_FMTBIT_S18_3LE | \ SNDRV_PCM_FMTBIT_S20_3LE | \ SNDRV_PCM_FMTBIT_S24_3LE | \ SNDRV_PCM_FMTBIT_S24_LE | \ SNDRV_PCM_FMTBIT_S32_LE) static int atmel_i2s_set_dai_fmt(struct snd_soc_dai *dai, unsigned int fmt) { struct atmel_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); dev->fmt = fmt; return 0; } static int atmel_i2s_prepare(struct snd_pcm_substream *substream, struct snd_soc_dai *dai) { struct atmel_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); bool is_playback = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK); unsigned int rhr, sr = 0; if (is_playback) { regmap_read(dev->regmap, ATMEL_I2SC_SR, &sr); if (sr & ATMEL_I2SC_SR_RXRDY) { /* * The RX Ready flag should not be set. However if here, * we flush (read) the Receive Holding Register to start * from a clean state. */ dev_dbg(dev->dev, "RXRDY is set\n"); regmap_read(dev->regmap, ATMEL_I2SC_RHR, &rhr); } } return 0; } static int atmel_i2s_get_gck_param(struct atmel_i2s_dev *dev, int fs) { int i, best; if (!dev->gclk) { dev_err(dev->dev, "cannot generate the I2S Master Clock\n"); return -EINVAL; } /* * Find the best possible settings to generate the I2S Master Clock * from the PLL Audio. */ dev->gck_param = NULL; best = INT_MAX; for (i = 0; i < ARRAY_SIZE(gck_params); ++i) { const struct atmel_i2s_gck_param *gck_param = &gck_params[i]; int val = abs(fs - gck_param->fs); if (val < best) { best = val; dev->gck_param = gck_param; } } return 0; } static int atmel_i2s_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params, struct snd_soc_dai *dai) { struct atmel_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); bool is_playback = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK); unsigned int mr = 0; int ret; switch (dev->fmt & SND_SOC_DAIFMT_FORMAT_MASK) { case SND_SOC_DAIFMT_I2S: mr |= ATMEL_I2SC_MR_FORMAT_I2S; break; default: dev_err(dev->dev, "unsupported bus format\n"); return -EINVAL; } switch (dev->fmt & SND_SOC_DAIFMT_MASTER_MASK) { case SND_SOC_DAIFMT_CBS_CFS: /* codec is slave, so cpu is master */ mr |= ATMEL_I2SC_MR_MODE_MASTER; ret = atmel_i2s_get_gck_param(dev, params_rate(params)); if (ret) return ret; break; case SND_SOC_DAIFMT_CBM_CFM: /* codec is master, so cpu is slave */ mr |= ATMEL_I2SC_MR_MODE_SLAVE; dev->gck_param = NULL; break; default: dev_err(dev->dev, "unsupported master/slave mode\n"); return -EINVAL; } switch (params_channels(params)) { case 1: if (is_playback) mr |= ATMEL_I2SC_MR_TXMONO; else mr |= ATMEL_I2SC_MR_RXMONO; break; case 2: break; default: dev_err(dev->dev, "unsupported number of audio channels\n"); return -EINVAL; } switch (params_format(params)) { case SNDRV_PCM_FORMAT_S8: mr |= ATMEL_I2SC_MR_DATALENGTH_8_BITS; break; case SNDRV_PCM_FORMAT_S16_LE: mr |= ATMEL_I2SC_MR_DATALENGTH_16_BITS; break; case SNDRV_PCM_FORMAT_S18_3LE: mr |= ATMEL_I2SC_MR_DATALENGTH_18_BITS | ATMEL_I2SC_MR_IWS; break; case SNDRV_PCM_FORMAT_S20_3LE: mr |= ATMEL_I2SC_MR_DATALENGTH_20_BITS | ATMEL_I2SC_MR_IWS; break; case SNDRV_PCM_FORMAT_S24_3LE: mr |= ATMEL_I2SC_MR_DATALENGTH_24_BITS | ATMEL_I2SC_MR_IWS; break; case SNDRV_PCM_FORMAT_S24_LE: mr |= ATMEL_I2SC_MR_DATALENGTH_24_BITS; break; case SNDRV_PCM_FORMAT_S32_LE: mr |= ATMEL_I2SC_MR_DATALENGTH_32_BITS; break; default: dev_err(dev->dev, "unsupported size/endianness for audio samples\n"); return -EINVAL; } return regmap_write(dev->regmap, ATMEL_I2SC_MR, mr); } static int atmel_i2s_switch_mck_generator(struct atmel_i2s_dev *dev, bool enabled) { unsigned int mr, mr_mask; unsigned long gclk_rate; int ret; mr = 0; mr_mask = (ATMEL_I2SC_MR_IMCKDIV_MASK | ATMEL_I2SC_MR_IMCKFS_MASK | ATMEL_I2SC_MR_IMCKMODE_MASK); if (!enabled) { /* Disable the I2S Master Clock generator. */ ret = regmap_write(dev->regmap, ATMEL_I2SC_CR, ATMEL_I2SC_CR_CKDIS); if (ret) return ret; /* Reset the I2S Master Clock generator settings. */ ret = regmap_update_bits(dev->regmap, ATMEL_I2SC_MR, mr_mask, mr); if (ret) return ret; /* Disable/unprepare the PMC generated clock. */ clk_disable_unprepare(dev->gclk); return 0; } if (!dev->gck_param) return -EINVAL; gclk_rate = dev->gck_param->mck * (dev->gck_param->imckdiv + 1); ret = clk_set_rate(dev->gclk, gclk_rate); if (ret) return ret; ret = clk_prepare_enable(dev->gclk); if (ret) return ret; /* Update the Mode Register to generate the I2S Master Clock. */ mr |= ATMEL_I2SC_MR_IMCKDIV(dev->gck_param->imckdiv); mr |= ATMEL_I2SC_MR_IMCKFS(dev->gck_param->imckfs); mr |= ATMEL_I2SC_MR_IMCKMODE_I2SMCK; ret = regmap_update_bits(dev->regmap, ATMEL_I2SC_MR, mr_mask, mr); if (ret) return ret; /* Finally enable the I2S Master Clock generator. */ return regmap_write(dev->regmap, ATMEL_I2SC_CR, ATMEL_I2SC_CR_CKEN); } static int atmel_i2s_trigger(struct snd_pcm_substream *substream, int cmd, struct snd_soc_dai *dai) { struct atmel_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); bool is_playback = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK); bool is_master, mck_enabled; unsigned int cr, mr; int err; switch (cmd) { case SNDRV_PCM_TRIGGER_START: case SNDRV_PCM_TRIGGER_RESUME: case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: cr = is_playback ? ATMEL_I2SC_CR_TXEN : ATMEL_I2SC_CR_RXEN; mck_enabled = true; break; case SNDRV_PCM_TRIGGER_STOP: case SNDRV_PCM_TRIGGER_SUSPEND: case SNDRV_PCM_TRIGGER_PAUSE_PUSH: cr = is_playback ? ATMEL_I2SC_CR_TXDIS : ATMEL_I2SC_CR_RXDIS; mck_enabled = false; break; default: return -EINVAL; } /* Read the Mode Register to retrieve the master/slave state. */ err = regmap_read(dev->regmap, ATMEL_I2SC_MR, &mr); if (err) return err; is_master = (mr & ATMEL_I2SC_MR_MODE_MASK) == ATMEL_I2SC_MR_MODE_MASTER; /* If master starts, enable the audio clock. */ if (is_master && mck_enabled) err = atmel_i2s_switch_mck_generator(dev, true); if (err) return err; err = regmap_write(dev->regmap, ATMEL_I2SC_CR, cr); if (err) return err; /* If master stops, disable the audio clock. */ if (is_master && !mck_enabled) err = atmel_i2s_switch_mck_generator(dev, false); return err; } static const struct snd_soc_dai_ops atmel_i2s_dai_ops = { .prepare = atmel_i2s_prepare, .trigger = atmel_i2s_trigger, .hw_params = atmel_i2s_hw_params, .set_fmt = atmel_i2s_set_dai_fmt, }; static int atmel_i2s_dai_probe(struct snd_soc_dai *dai) { struct atmel_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); snd_soc_dai_init_dma_data(dai, &dev->playback, &dev->capture); return 0; } static struct snd_soc_dai_driver atmel_i2s_dai = { .probe = atmel_i2s_dai_probe, .playback = { .channels_min = 1, .channels_max = 2, .rates = ATMEL_I2S_RATES, .formats = ATMEL_I2S_FORMATS, }, .capture = { .channels_min = 1, .channels_max = 2, .rates = ATMEL_I2S_RATES, .formats = ATMEL_I2S_FORMATS, }, .ops = &atmel_i2s_dai_ops, .symmetric_rates = 1, }; static const struct snd_soc_component_driver atmel_i2s_component = { .name = "atmel-i2s", }; static int atmel_i2s_sama5d2_mck_init(struct atmel_i2s_dev *dev, struct device_node *np) { struct clk *muxclk; int err; if (!dev->gclk) return 0; /* muxclk is optional, so we return error for probe defer only */ muxclk = devm_clk_get(dev->dev, "muxclk"); if (IS_ERR(muxclk)) { err = PTR_ERR(muxclk); if (err == -EPROBE_DEFER) return -EPROBE_DEFER; dev_warn(dev->dev, "failed to get the I2S clock control: %d\n", err); return 0; } return clk_set_parent(muxclk, dev->gclk); } static const struct atmel_i2s_caps atmel_i2s_sama5d2_caps = { .mck_init = atmel_i2s_sama5d2_mck_init, }; static const struct of_device_id atmel_i2s_dt_ids[] = { { .compatible = "atmel,sama5d2-i2s", .data = (void *)&atmel_i2s_sama5d2_caps, }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, atmel_i2s_dt_ids); static int atmel_i2s_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; const struct of_device_id *match; struct atmel_i2s_dev *dev; struct resource *mem; struct regmap *regmap; void __iomem *base; int irq; int err = -ENXIO; unsigned int pcm_flags = 0; unsigned int version; /* Get memory for driver data. */ dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); if (!dev) return -ENOMEM; /* Get hardware capabilities. */ match = of_match_node(atmel_i2s_dt_ids, np); if (match) dev->caps = match->data; /* Map I/O registers. */ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); base = devm_ioremap_resource(&pdev->dev, mem); if (IS_ERR(base)) return PTR_ERR(base); regmap = devm_regmap_init_mmio(&pdev->dev, base, &atmel_i2s_regmap_config); if (IS_ERR(regmap)) return PTR_ERR(regmap); /* Request IRQ. */ irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; err = devm_request_irq(&pdev->dev, irq, atmel_i2s_interrupt, 0, dev_name(&pdev->dev), dev); if (err) return err; /* Get the peripheral clock. */ dev->pclk = devm_clk_get(&pdev->dev, "pclk"); if (IS_ERR(dev->pclk)) { err = PTR_ERR(dev->pclk); dev_err(&pdev->dev, "failed to get the peripheral clock: %d\n", err); return err; } /* Get audio clock to generate the I2S Master Clock (I2S_MCK) */ dev->gclk = devm_clk_get(&pdev->dev, "gclk"); if (IS_ERR(dev->gclk)) { if (PTR_ERR(dev->gclk) == -EPROBE_DEFER) return -EPROBE_DEFER; /* Master Mode not supported */ dev->gclk = NULL; } dev->dev = &pdev->dev; dev->regmap = regmap; platform_set_drvdata(pdev, dev); /* Do hardware specific settings to initialize I2S_MCK generator */ if (dev->caps && dev->caps->mck_init) { err = dev->caps->mck_init(dev, np); if (err) return err; } /* Enable the peripheral clock. */ err = clk_prepare_enable(dev->pclk); if (err) return err; /* Get IP version. */ regmap_read(dev->regmap, ATMEL_I2SC_VERSION, &version); dev_info(&pdev->dev, "hw version: %#x\n", version); /* Enable error interrupts. */ regmap_write(dev->regmap, ATMEL_I2SC_IER, ATMEL_I2SC_INT_RXOR | ATMEL_I2SC_INT_TXUR); err = devm_snd_soc_register_component(&pdev->dev, &atmel_i2s_component, &atmel_i2s_dai, 1); if (err) { dev_err(&pdev->dev, "failed to register DAI: %d\n", err); clk_disable_unprepare(dev->pclk); return err; } /* Prepare DMA config. */ dev->playback.addr = (dma_addr_t)mem->start + ATMEL_I2SC_THR; dev->playback.maxburst = 1; dev->capture.addr = (dma_addr_t)mem->start + ATMEL_I2SC_RHR; dev->capture.maxburst = 1; if (of_property_match_string(np, "dma-names", "rx-tx") == 0) pcm_flags |= SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX; err = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, pcm_flags); if (err) { dev_err(&pdev->dev, "failed to register PCM: %d\n", err); clk_disable_unprepare(dev->pclk); return err; } return 0; } static int atmel_i2s_remove(struct platform_device *pdev) { struct atmel_i2s_dev *dev = platform_get_drvdata(pdev); clk_disable_unprepare(dev->pclk); return 0; } static struct platform_driver atmel_i2s_driver = { .driver = { .name = "atmel_i2s", .of_match_table = of_match_ptr(atmel_i2s_dt_ids), }, .probe = atmel_i2s_probe, .remove = atmel_i2s_remove, }; module_platform_driver(atmel_i2s_driver); MODULE_DESCRIPTION("Atmel I2S Controller driver"); MODULE_AUTHOR("Cyrille Pitchen "); MODULE_LICENSE("GPL v2");