[PATCH 2/2] ASoC: atmel-i2s: add driver for the new Atmel I2S controller

Cyrille Pitchen
2015-09-28T15:05:59Z

This patch adds support for the Atmel I2S controller embedded into
sama5d2x SoCs.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
---
sound/soc/atmel/Kconfig | 10 +
sound/soc/atmel/Makefile | 2 +
sound/soc/atmel/atmel-i2s.c | 760 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 772 insertions(+)
create mode 100644 sound/soc/atmel/atmel-i2s.c

diff --git a/sound/soc/atmel/Kconfig b/sound/soc/atmel/Kconfig
index 1489cd461aec..c026c207a386 100644
--- a/sound/soc/atmel/Kconfig
+++ b/sound/soc/atmel/Kconfig
@@ -30,6 +30,16 @@ config SND_ATMEL_SOC_SSC
default y if SND_ATMEL_SOC_SSC_DMA=y || SND_ATMEL_SOC_SSC_PDC=y
default m if SND_ATMEL_SOC_SSC_DMA=m || SND_ATMEL_SOC_SSC_PDC=m

+config SND_ATMEL_SOC_I2S
+ tristate "SoC Audio support for the Atmel I2S module"
+ select SND_SOC_GENERIC_DMAENGINE_PCM
+ select REGMAP_MMIO
+ depends on OF && (ARCH_AT91 || COMPILE_TEST)
+ help
+ Say Y or M if you want to add support for codecs attached to
+ the Atmel I2S interface. You will also need
+ to select the audio interfaces to support below.
+
config SND_AT91_SOC_SAM9G20_WM8731
tristate "SoC Audio support for WM8731-based At91sam9g20 evaluation board"
depends on ARCH_AT91 || COMPILE_TEST
diff --git a/sound/soc/atmel/Makefile b/sound/soc/atmel/Makefile
index b327e5cc8de3..4d960464aecb 100644
--- a/sound/soc/atmel/Makefile
+++ b/sound/soc/atmel/Makefile
@@ -2,10 +2,12 @@
snd-soc-atmel-pcm-pdc-objs := atmel-pcm-pdc.o
snd-soc-atmel-pcm-dma-objs := atmel-pcm-dma.o
snd-soc-atmel_ssc_dai-objs := atmel_ssc_dai.o
+snd-soc-atmel-i2s-objs := atmel-i2s.o

obj-$(CONFIG_SND_ATMEL_SOC_PDC) += snd-soc-atmel-pcm-pdc.o
obj-$(CONFIG_SND_ATMEL_SOC_DMA) += snd-soc-atmel-pcm-dma.o
obj-$(CONFIG_SND_ATMEL_SOC_SSC) += snd-soc-atmel_ssc_dai.o
+obj-$(CONFIG_SND_ATMEL_SOC_I2S) += snd-soc-atmel-i2s.o

# AT91 Machine Support
snd-soc-sam9g20-wm8731-objs := sam9g20_wm8731.o
diff --git a/sound/soc/atmel/atmel-i2s.c b/sound/soc/atmel/atmel-i2s.c
new file mode 100644
index 000000000000..7d44ac4e6ac9
--- /dev/null
+++ b/sound/soc/atmel/atmel-i2s.c
@@ -0,0 +1,760 @@
+/*
+ * Driver for Atmel I2S controller
+ *
+ * Copyright (C) 2015 Atmel Corporation
+ *
+ * Author: Cyrille Pitchen <cyrille.pitchen@atmel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/mfd/syscon.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+#include <sound/dmaengine_pcm.h>
+
+#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 clk *aclk;
+ 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;
+
+ 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);
+ }
+
+ 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);
+
+ }
+
+ return IRQ_HANDLED;
+}
+
+#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) {
+ 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->aclk) {
+ 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:
+ mr |= is_playback ? ATMEL_I2SC_MR_TXMONO : ATMEL_I2SC_MR_RXMONO;
+ break;
+ case 2:
+ break;
+ default:
+ dev_err(dev->dev, "unsupported number of audio channels\n");
+ break;
+ }
+
+ 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 aclk_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);
+
+ /* Disable/unprepare the PLL audio clock. */
+ clk_disable_unprepare(dev->aclk);
+ return 0;
+ }
+
+ if (!dev->gck_param)
+ return -EINVAL;
+
+ aclk_rate = dev->gck_param->mck * (dev->gck_param->imckdiv+1);
+
+ /* Fist change the PLL audio clock frequency ... */
+ ret = clk_set_rate(dev->aclk, aclk_rate);
+ if (ret)
+ return ret;
+
+ /*
+ * ... then set the PMC generated clock rate to the very same frequency
+ * to set the gclk parent to aclk.
+ */
+ ret = clk_set_rate(dev->gclk, aclk_rate);
+ if (ret)
+ return ret;
+
+ /* Prepare and enable the PLL audio clock first ... */
+ ret = clk_prepare_enable(dev->aclk);
+ if (ret)
+ return ret;
+
+ /* ... then prepare and enable the PMC generated clock. */
+ 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)
+{
+ #define SFR_I2SCLKSEL 0x90U
+ struct regmap *sfr;
+ int id;
+
+ id = of_alias_get_id(np, "i2s");
+ if (id < 0) {
+ dev_err(dev->dev, "failed to get alias ID\n");
+ return id;
+ }
+ if (id > 1) {
+ dev_err(dev->dev, "invalid I2S controller ID: %d\n", id);
+ return -EINVAL;
+ }
+
+ sfr = syscon_regmap_lookup_by_compatible("atmel,sama5d2-sfr");
+ if (IS_ERR(sfr)) {
+ dev_err(dev->dev, "failed to get SFR syscon\n");
+ return PTR_ERR(sfr);
+ }
+
+ return regmap_update_bits(sfr, SFR_I2SCLKSEL, BIT(id), BIT(id));
+}
+
+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);
+ dev->caps = match ? match->data : NULL;
+
+ /* 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 clocks to generate the I2S Master Clock (I2S_MCK) */
+ dev->aclk = devm_clk_get(&pdev->dev, "aclk");
+ dev->gclk = devm_clk_get(&pdev->dev, "gclk");
+ if (IS_ERR(dev->aclk) && IS_ERR(dev->gclk)) {
+ /* Master Mode not supported */
+ dev->aclk = NULL;
+ dev->gclk = NULL;
+ } else if (IS_ERR(dev->gclk)) {
+ err = PTR_ERR(dev->gclk);
+ dev_err(&pdev->dev,
+ "failed to get the PMC generated clock: %d\n", err);
+ return err;
+ } else if (IS_ERR(dev->aclk)) {
+ err = PTR_ERR(dev->aclk);
+ dev_err(&pdev->dev,
+ "failed to get the PLL audio clock: %d\n", err);
+ return err;
+ }
+
+ /* 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;
+
+ dev->dev = &pdev->dev;
+ dev->regmap = regmap;
+ platform_set_drvdata(pdev, dev);
+
+ /* 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 <cyrille.pitchen@atmel.com>");
+MODULE_LICENSE("GPL v2");
--
1.8.2.2