ASoC: stm32: Add SPDIFRX support

Add SPDIFRX support to STM32.

Signed-off-by: olivier moysan <olivier.moysan@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

3 files changed, 1012 insertions, 0 deletions

diff --git a/sound/soc/stm/Kconfig b/sound/soc/stm/Kconfig
index 23600a5dd46f..3398e6c57f37 100644
--- a/sound/soc/stm/Kconfig
+++ b/sound/soc/stm/Kconfig
@@ -18,4 +18,14 @@ config SND_SOC_STM32_I2S
 	help
 	  Say Y if you want to enable I2S for STM32
 
+config SND_SOC_STM32_SPDIFRX
+	tristate "STM32 S/PDIF receiver (SPDIFRX) support"
+	depends on ARCH_STM32 || COMPILE_TEST
+	depends on SND_SOC
+	select SND_SOC_GENERIC_DMAENGINE_PCM
+	select REGMAP_MMIO
+	select SND_SOC_SPDIF
+	help
+	  Say Y if you want to enable S/PDIF capture for STM32
+
 endmenu
diff --git a/sound/soc/stm/Makefile b/sound/soc/stm/Makefile
index 4140c67fa47b..4ed22e648a9a 100644
--- a/sound/soc/stm/Makefile
+++ b/sound/soc/stm/Makefile
@@ -8,3 +8,7 @@ obj-$(CONFIG_SND_SOC_STM32_SAI) += snd-soc-stm32-sai.o
 # I2S
 snd-soc-stm32-i2s-objs := stm32_i2s.o
 obj-$(CONFIG_SND_SOC_STM32_I2S) += snd-soc-stm32-i2s.o
+
+# SPDIFRX
+snd-soc-stm32-spdifrx-objs := stm32_spdifrx.o
+obj-$(CONFIG_SND_SOC_STM32_SPDIFRX) += snd-soc-stm32-spdifrx.o
diff --git a/sound/soc/stm/stm32_spdifrx.c b/sound/soc/stm/stm32_spdifrx.c
new file mode 100644
index 000000000000..4e4250bdb75a
--- /dev/null
+++ b/sound/soc/stm/stm32_spdifrx.c
@@ -0,0 +1,998 @@
+/*
+ * STM32 ALSA SoC Digital Audio Interface (SPDIF-rx) driver.
+ *
+ * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
+ * Author(s): Olivier Moysan <olivier.moysan@st.com> for STMicroelectronics.
+ *
+ * License terms: GPL V2.0.
+ *
+ * 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.
+ */
+
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+
+#include <sound/dmaengine_pcm.h>
+#include <sound/pcm_params.h>
+
+/* SPDIF-rx Register Map */
+#define STM32_SPDIFRX_CR	0x00
+#define STM32_SPDIFRX_IMR	0x04
+#define STM32_SPDIFRX_SR	0x08
+#define STM32_SPDIFRX_IFCR	0x0C
+#define STM32_SPDIFRX_DR	0x10
+#define STM32_SPDIFRX_CSR	0x14
+#define STM32_SPDIFRX_DIR	0x18
+
+/* Bit definition for SPDIF_CR register */
+#define SPDIFRX_CR_SPDIFEN_SHIFT	0
+#define SPDIFRX_CR_SPDIFEN_MASK	GENMASK(1, SPDIFRX_CR_SPDIFEN_SHIFT)
+#define SPDIFRX_CR_SPDIFENSET(x)	((x) << SPDIFRX_CR_SPDIFEN_SHIFT)
+
+#define SPDIFRX_CR_RXDMAEN	BIT(2)
+#define SPDIFRX_CR_RXSTEO	BIT(3)
+
+#define SPDIFRX_CR_DRFMT_SHIFT	4
+#define SPDIFRX_CR_DRFMT_MASK	GENMASK(5, SPDIFRX_CR_DRFMT_SHIFT)
+#define SPDIFRX_CR_DRFMTSET(x)	((x) << SPDIFRX_CR_DRFMT_SHIFT)
+
+#define SPDIFRX_CR_PMSK		BIT(6)
+#define SPDIFRX_CR_VMSK		BIT(7)
+#define SPDIFRX_CR_CUMSK	BIT(8)
+#define SPDIFRX_CR_PTMSK	BIT(9)
+#define SPDIFRX_CR_CBDMAEN	BIT(10)
+#define SPDIFRX_CR_CHSEL_SHIFT	11
+#define SPDIFRX_CR_CHSEL	BIT(SPDIFRX_CR_CHSEL_SHIFT)
+
+#define SPDIFRX_CR_NBTR_SHIFT	12
+#define SPDIFRX_CR_NBTR_MASK	GENMASK(13, SPDIFRX_CR_NBTR_SHIFT)
+#define SPDIFRX_CR_NBTRSET(x)	((x) << SPDIFRX_CR_NBTR_SHIFT)
+
+#define SPDIFRX_CR_WFA		BIT(14)
+
+#define SPDIFRX_CR_INSEL_SHIFT	16
+#define SPDIFRX_CR_INSEL_MASK	GENMASK(18, PDIFRX_CR_INSEL_SHIFT)
+#define SPDIFRX_CR_INSELSET(x)	((x) << SPDIFRX_CR_INSEL_SHIFT)
+
+#define SPDIFRX_CR_CKSEN_SHIFT	20
+#define SPDIFRX_CR_CKSEN	BIT(20)
+#define SPDIFRX_CR_CKSBKPEN	BIT(21)
+
+/* Bit definition for SPDIFRX_IMR register */
+#define SPDIFRX_IMR_RXNEI	BIT(0)
+#define SPDIFRX_IMR_CSRNEIE	BIT(1)
+#define SPDIFRX_IMR_PERRIE	BIT(2)
+#define SPDIFRX_IMR_OVRIE	BIT(3)
+#define SPDIFRX_IMR_SBLKIE	BIT(4)
+#define SPDIFRX_IMR_SYNCDIE	BIT(5)
+#define SPDIFRX_IMR_IFEIE	BIT(6)
+
+#define SPDIFRX_XIMR_MASK	GENMASK(6, 0)
+
+/* Bit definition for SPDIFRX_SR register */
+#define SPDIFRX_SR_RXNE		BIT(0)
+#define SPDIFRX_SR_CSRNE	BIT(1)
+#define SPDIFRX_SR_PERR		BIT(2)
+#define SPDIFRX_SR_OVR		BIT(3)
+#define SPDIFRX_SR_SBD		BIT(4)
+#define SPDIFRX_SR_SYNCD	BIT(5)
+#define SPDIFRX_SR_FERR		BIT(6)
+#define SPDIFRX_SR_SERR		BIT(7)
+#define SPDIFRX_SR_TERR		BIT(8)
+
+#define SPDIFRX_SR_WIDTH5_SHIFT	16
+#define SPDIFRX_SR_WIDTH5_MASK	GENMASK(30, PDIFRX_SR_WIDTH5_SHIFT)
+#define SPDIFRX_SR_WIDTH5SET(x)	((x) << SPDIFRX_SR_WIDTH5_SHIFT)
+
+/* Bit definition for SPDIFRX_IFCR register */
+#define SPDIFRX_IFCR_PERRCF	BIT(2)
+#define SPDIFRX_IFCR_OVRCF	BIT(3)
+#define SPDIFRX_IFCR_SBDCF	BIT(4)
+#define SPDIFRX_IFCR_SYNCDCF	BIT(5)
+
+#define SPDIFRX_XIFCR_MASK	GENMASK(5, 2)
+
+/* Bit definition for SPDIFRX_DR register (DRFMT = 0b00) */
+#define SPDIFRX_DR0_DR_SHIFT	0
+#define SPDIFRX_DR0_DR_MASK	GENMASK(23, SPDIFRX_DR0_DR_SHIFT)
+#define SPDIFRX_DR0_DRSET(x)	((x) << SPDIFRX_DR0_DR_SHIFT)
+
+#define SPDIFRX_DR0_PE		BIT(24)
+
+#define SPDIFRX_DR0_V		BIT(25)
+#define SPDIFRX_DR0_U		BIT(26)
+#define SPDIFRX_DR0_C		BIT(27)
+
+#define SPDIFRX_DR0_PT_SHIFT	28
+#define SPDIFRX_DR0_PT_MASK	GENMASK(29, SPDIFRX_DR0_PT_SHIFT)
+#define SPDIFRX_DR0_PTSET(x)	((x) << SPDIFRX_DR0_PT_SHIFT)
+
+/* Bit definition for SPDIFRX_DR register (DRFMT = 0b01) */
+#define  SPDIFRX_DR1_PE		BIT(0)
+#define  SPDIFRX_DR1_V		BIT(1)
+#define  SPDIFRX_DR1_U		BIT(2)
+#define  SPDIFRX_DR1_C		BIT(3)
+
+#define  SPDIFRX_DR1_PT_SHIFT	4
+#define  SPDIFRX_DR1_PT_MASK	GENMASK(5, SPDIFRX_DR1_PT_SHIFT)
+#define  SPDIFRX_DR1_PTSET(x)	((x) << SPDIFRX_DR1_PT_SHIFT)
+
+#define SPDIFRX_DR1_DR_SHIFT	8
+#define SPDIFRX_DR1_DR_MASK	GENMASK(31, SPDIFRX_DR1_DR_SHIFT)
+#define SPDIFRX_DR1_DRSET(x)	((x) << SPDIFRX_DR1_DR_SHIFT)
+
+/* Bit definition for SPDIFRX_DR register (DRFMT = 0b10) */
+#define SPDIFRX_DR1_DRNL1_SHIFT	0
+#define SPDIFRX_DR1_DRNL1_MASK	GENMASK(15, SPDIFRX_DR1_DRNL1_SHIFT)
+#define SPDIFRX_DR1_DRNL1SET(x)	((x) << SPDIFRX_DR1_DRNL1_SHIFT)
+
+#define SPDIFRX_DR1_DRNL2_SHIFT	16
+#define SPDIFRX_DR1_DRNL2_MASK	GENMASK(31, SPDIFRX_DR1_DRNL2_SHIFT)
+#define SPDIFRX_DR1_DRNL2SET(x)	((x) << SPDIFRX_DR1_DRNL2_SHIFT)
+
+/* Bit definition for SPDIFRX_CSR register */
+#define SPDIFRX_CSR_USR_SHIFT	0
+#define SPDIFRX_CSR_USR_MASK	GENMASK(15, SPDIFRX_CSR_USR_SHIFT)
+#define SPDIFRX_CSR_USRGET(x)	(((x) & SPDIFRX_CSR_USR_MASK)\
+				>> SPDIFRX_CSR_USR_SHIFT)
+
+#define SPDIFRX_CSR_CS_SHIFT	16
+#define SPDIFRX_CSR_CS_MASK	GENMASK(23, SPDIFRX_CSR_CS_SHIFT)
+#define SPDIFRX_CSR_CSGET(x)	(((x) & SPDIFRX_CSR_CS_MASK)\
+				>> SPDIFRX_CSR_CS_SHIFT)
+
+#define SPDIFRX_CSR_SOB		BIT(24)
+
+/* Bit definition for SPDIFRX_DIR register */
+#define SPDIFRX_DIR_THI_SHIFT	0
+#define SPDIFRX_DIR_THI_MASK	GENMASK(12, SPDIFRX_DIR_THI_SHIFT)
+#define SPDIFRX_DIR_THI_SET(x)	((x) << SPDIFRX_DIR_THI_SHIFT)
+
+#define SPDIFRX_DIR_TLO_SHIFT	16
+#define SPDIFRX_DIR_TLO_MASK	GENMASK(28, SPDIFRX_DIR_TLO_SHIFT)
+#define SPDIFRX_DIR_TLO_SET(x)	((x) << SPDIFRX_DIR_TLO_SHIFT)
+
+#define SPDIFRX_SPDIFEN_DISABLE	0x0
+#define SPDIFRX_SPDIFEN_SYNC	0x1
+#define SPDIFRX_SPDIFEN_ENABLE	0x3
+
+#define SPDIFRX_IN1		0x1
+#define SPDIFRX_IN2		0x2
+#define SPDIFRX_IN3		0x3
+#define SPDIFRX_IN4		0x4
+#define SPDIFRX_IN5		0x5
+#define SPDIFRX_IN6		0x6
+#define SPDIFRX_IN7		0x7
+#define SPDIFRX_IN8		0x8
+
+#define SPDIFRX_NBTR_NONE	0x0
+#define SPDIFRX_NBTR_3		0x1
+#define SPDIFRX_NBTR_15		0x2
+#define SPDIFRX_NBTR_63		0x3
+
+#define SPDIFRX_DRFMT_RIGHT	0x0
+#define SPDIFRX_DRFMT_LEFT	0x1
+#define SPDIFRX_DRFMT_PACKED	0x2
+
+/* 192 CS bits in S/PDIF frame. i.e 24 CS bytes */
+#define SPDIFRX_CS_BYTES_NB	24
+#define SPDIFRX_UB_BYTES_NB	48
+
+/*
+ * CSR register is retrieved as a 32 bits word
+ * It contains 1 channel status byte and 2 user data bytes
+ * 2 S/PDIF frames are acquired to get all CS/UB bits
+ */
+#define SPDIFRX_CSR_BUF_LENGTH	(SPDIFRX_CS_BYTES_NB * 4 * 2)
+
+/**
+ * struct stm32_spdifrx_data - private data of SPDIFRX
+ * @pdev: device data pointer
+ * @base: mmio register base virtual address
+ * @regmap: SPDIFRX register map pointer
+ * @regmap_conf: SPDIFRX register map configuration pointer
+ * @cs_completion: channel status retrieving completion
+ * @kclk: kernel clock feeding the SPDIFRX clock generator
+ * @dma_params: dma configuration data for rx channel
+ * @substream: PCM substream data pointer
+ * @dmab: dma buffer info pointer
+ * @ctrl_chan: dma channel for S/PDIF control bits
+ * @desc:dma async transaction descriptor
+ * @slave_config: dma slave channel runtime config pointer
+ * @phys_addr: SPDIFRX registers physical base address
+ * @lock: synchronization enabling lock
+ * @cs: channel status buffer
+ * @ub: user data buffer
+ * @irq: SPDIFRX interrupt line
+ * @refcount: keep count of opened DMA channels
+ */
+struct stm32_spdifrx_data {
+	struct platform_device *pdev;
+	void __iomem *base;
+	struct regmap *regmap;
+	const struct regmap_config *regmap_conf;
+	struct completion cs_completion;
+	struct clk *kclk;
+	struct snd_dmaengine_dai_dma_data dma_params;
+	struct snd_pcm_substream *substream;
+	struct snd_dma_buffer *dmab;
+	struct dma_chan *ctrl_chan;
+	struct dma_async_tx_descriptor *desc;
+	struct dma_slave_config slave_config;
+	dma_addr_t phys_addr;
+	spinlock_t lock;  /* Sync enabling lock */
+	unsigned char cs[SPDIFRX_CS_BYTES_NB];
+	unsigned char ub[SPDIFRX_UB_BYTES_NB];
+	int irq;
+	int refcount;
+};
+
+static void stm32_spdifrx_dma_complete(void *data)
+{
+	struct stm32_spdifrx_data *spdifrx = (struct stm32_spdifrx_data *)data;
+	struct platform_device *pdev = spdifrx->pdev;
+	u32 *p_start = (u32 *)spdifrx->dmab->area;
+	u32 *p_end = p_start + (2 * SPDIFRX_CS_BYTES_NB) - 1;
+	u32 *ptr = p_start;
+	u16 *ub_ptr = (short *)spdifrx->ub;
+	int i = 0;
+
+	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
+			   SPDIFRX_CR_CBDMAEN,
+			   (unsigned int)~SPDIFRX_CR_CBDMAEN);
+
+	if (!spdifrx->dmab->area)
+		return;
+
+	while (ptr <= p_end) {
+		if (*ptr & SPDIFRX_CSR_SOB)
+			break;
+		ptr++;
+	}
+
+	if (ptr > p_end) {
+		dev_err(&pdev->dev, "Start of S/PDIF block not found\n");
+		return;
+	}
+
+	while (i < SPDIFRX_CS_BYTES_NB) {
+		spdifrx->cs[i] = (unsigned char)SPDIFRX_CSR_CSGET(*ptr);
+		*ub_ptr++ = SPDIFRX_CSR_USRGET(*ptr++);
+		if (ptr > p_end) {
+			dev_err(&pdev->dev, "Failed to get channel status\n");
+			return;
+		}
+		i++;
+	}
+
+	complete(&spdifrx->cs_completion);
+}
+
+static int stm32_spdifrx_dma_ctrl_start(struct stm32_spdifrx_data *spdifrx)
+{
+	dma_cookie_t cookie;
+	int err;
+
+	spdifrx->desc = dmaengine_prep_slave_single(spdifrx->ctrl_chan,
+						    spdifrx->dmab->addr,
+						    SPDIFRX_CSR_BUF_LENGTH,
+						    DMA_DEV_TO_MEM,
+						    DMA_CTRL_ACK);
+	if (!spdifrx->desc)
+		return -EINVAL;
+
+	spdifrx->desc->callback = stm32_spdifrx_dma_complete;
+	spdifrx->desc->callback_param = spdifrx;
+	cookie = dmaengine_submit(spdifrx->desc);
+	err = dma_submit_error(cookie);
+	if (err)
+		return -EINVAL;
+
+	dma_async_issue_pending(spdifrx->ctrl_chan);
+
+	return 0;
+}
+
+static void stm32_spdifrx_dma_ctrl_stop(struct stm32_spdifrx_data *spdifrx)
+{
+	dmaengine_terminate_async(spdifrx->ctrl_chan);
+}
+
+static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
+{
+	int cr, cr_mask, imr, ret;
+
+	/* Enable IRQs */
+	imr = SPDIFRX_IMR_IFEIE | SPDIFRX_IMR_SYNCDIE | SPDIFRX_IMR_PERRIE;
+	ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR, imr, imr);
+	if (ret)
+		return ret;
+
+	spin_lock(&spdifrx->lock);
+
+	spdifrx->refcount++;
+
+	regmap_read(spdifrx->regmap, STM32_SPDIFRX_CR, &cr);
+
+	if (!(cr & SPDIFRX_CR_SPDIFEN_MASK)) {
+		/*
+		 * Start sync if SPDIFRX is still in idle state.
+		 * SPDIFRX reception enabled when sync done
+		 */
+		dev_dbg(&spdifrx->pdev->dev, "start synchronization\n");
+
+		/*
+		 * SPDIFRX configuration:
+		 * Wait for activity before starting sync process. This avoid
+		 * to issue sync errors when spdif signal is missing on input.
+		 * Preamble, CS, user, validity and parity error bits not copied
+		 * to DR register.
+		 */
+		cr = SPDIFRX_CR_WFA | SPDIFRX_CR_PMSK | SPDIFRX_CR_VMSK |
+		     SPDIFRX_CR_CUMSK | SPDIFRX_CR_PTMSK | SPDIFRX_CR_RXSTEO;
+		cr_mask = cr;
+
+		cr |= SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_SYNC);
+		cr_mask |= SPDIFRX_CR_SPDIFEN_MASK;
+		ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
+					 cr_mask, cr);
+		if (ret < 0)
+			dev_err(&spdifrx->pdev->dev,
+				"Failed to start synchronization\n");
+	}
+
+	spin_unlock(&spdifrx->lock);
+
+	return ret;
+}
+
+static void stm32_spdifrx_stop(struct stm32_spdifrx_data *spdifrx)
+{
+	int cr, cr_mask, reg;
+
+	spin_lock(&spdifrx->lock);
+
+	if (--spdifrx->refcount) {
+		spin_unlock(&spdifrx->lock);
+		return;
+	}
+
+	cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_DISABLE);
+	cr_mask = SPDIFRX_CR_SPDIFEN_MASK | SPDIFRX_CR_RXDMAEN;
+
+	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR, cr_mask, cr);
+
+	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR,
+			   SPDIFRX_XIMR_MASK, 0);
+
+	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IFCR,
+			   SPDIFRX_XIFCR_MASK, SPDIFRX_XIFCR_MASK);
+
+	/* dummy read to clear CSRNE and RXNE in status register */
+	regmap_read(spdifrx->regmap, STM32_SPDIFRX_DR, &reg);
+	regmap_read(spdifrx->regmap, STM32_SPDIFRX_CSR, &reg);
+
+	spin_unlock(&spdifrx->lock);
+}
+
+static int stm32_spdifrx_dma_ctrl_register(struct device *dev,
+					   struct stm32_spdifrx_data *spdifrx)
+{
+	int ret;
+
+	spdifrx->dmab = devm_kzalloc(dev, sizeof(struct snd_dma_buffer),
+				     GFP_KERNEL);
+	if (!spdifrx->dmab)
+		return -ENOMEM;
+
+	spdifrx->dmab->dev.type = SNDRV_DMA_TYPE_DEV_IRAM;
+	spdifrx->dmab->dev.dev = dev;
+	ret = snd_dma_alloc_pages(spdifrx->dmab->dev.type, dev,
+				  SPDIFRX_CSR_BUF_LENGTH, spdifrx->dmab);
+	if (ret < 0) {
+		dev_err(dev, "snd_dma_alloc_pages returned error %d\n", ret);
+		return ret;
+	}
+
+	spdifrx->ctrl_chan = dma_request_chan(dev, "rx-ctrl");
+	if (!spdifrx->ctrl_chan) {
+		dev_err(dev, "dma_request_slave_channel failed\n");
+		return -EINVAL;
+	}
+
+	spdifrx->slave_config.direction = DMA_DEV_TO_MEM;
+	spdifrx->slave_config.src_addr = (dma_addr_t)(spdifrx->phys_addr +
+					 STM32_SPDIFRX_CSR);
+	spdifrx->slave_config.dst_addr = spdifrx->dmab->addr;
+	spdifrx->slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	spdifrx->slave_config.src_maxburst = 1;
+
+	ret = dmaengine_slave_config(spdifrx->ctrl_chan,
+				     &spdifrx->slave_config);
+	if (ret < 0) {
+		dev_err(dev, "dmaengine_slave_config returned error %d\n", ret);
+		dma_release_channel(spdifrx->ctrl_chan);
+		spdifrx->ctrl_chan = NULL;
+	}
+
+	return ret;
+};
+
+static const char * const spdifrx_enum_input[] = {
+	"in0", "in1", "in2", "in3"
+};
+
+/*  By default CS bits are retrieved from channel A */
+static const char * const spdifrx_enum_cs_channel[] = {
+	"A", "B"
+};
+
+static SOC_ENUM_SINGLE_DECL(ctrl_enum_input,
+			    STM32_SPDIFRX_CR, SPDIFRX_CR_INSEL_SHIFT,
+			    spdifrx_enum_input);
+
+static SOC_ENUM_SINGLE_DECL(ctrl_enum_cs_channel,
+			    STM32_SPDIFRX_CR, SPDIFRX_CR_CHSEL_SHIFT,
+			    spdifrx_enum_cs_channel);
+
+static int stm32_spdifrx_info(struct snd_kcontrol *kcontrol,
+			      struct snd_ctl_elem_info *uinfo)
+{
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
+	uinfo->count = 1;
+
+	return 0;
+}
+
+static int stm32_spdifrx_ub_info(struct snd_kcontrol *kcontrol,
+				 struct snd_ctl_elem_info *uinfo)
+{
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
+	uinfo->count = 1;
+
+	return 0;
+}
+
+static int stm32_spdifrx_get_ctrl_data(struct stm32_spdifrx_data *spdifrx)
+{
+	int ret = 0;
+
+	memset(spdifrx->cs, 0, SPDIFRX_CS_BYTES_NB);
+	memset(spdifrx->ub, 0, SPDIFRX_UB_BYTES_NB);
+
+	ret = stm32_spdifrx_dma_ctrl_start(spdifrx);
+	if (ret < 0)
+		return ret;
+
+	ret = clk_prepare_enable(spdifrx->kclk);
+	if (ret) {
+		dev_err(&spdifrx->pdev->dev, "Enable kclk failed: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
+				 SPDIFRX_CR_CBDMAEN, SPDIFRX_CR_CBDMAEN);
+	if (ret < 0)
+		goto end;
+
+	ret = stm32_spdifrx_start_sync(spdifrx);
+	if (ret < 0)
+		goto end;
+
+	if (wait_for_completion_interruptible_timeout(&spdifrx->cs_completion,
+						      msecs_to_jiffies(100))
+						      <= 0) {
+		dev_err(&spdifrx->pdev->dev, "Failed to get control data\n");
+		ret = -EAGAIN;
+	}
+
+	stm32_spdifrx_stop(spdifrx);
+	stm32_spdifrx_dma_ctrl_stop(spdifrx);
+
+end:
+	clk_disable_unprepare(spdifrx->kclk);
+
+	return ret;
+}
+
+static int stm32_spdifrx_capture_get(struct snd_kcontrol *kcontrol,
+				     struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
+	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
+
+	stm32_spdifrx_get_ctrl_data(spdifrx);
+
+	ucontrol->value.iec958.status[0] = spdifrx->cs[0];
+	ucontrol->value.iec958.status[1] = spdifrx->cs[1];
+	ucontrol->value.iec958.status[2] = spdifrx->cs[2];
+	ucontrol->value.iec958.status[3] = spdifrx->cs[3];
+	ucontrol->value.iec958.status[4] = spdifrx->cs[4];
+
+	return 0;
+}
+
+static int stm32_spdif_user_bits_get(struct snd_kcontrol *kcontrol,
+				     struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
+	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
+
+	stm32_spdifrx_get_ctrl_data(spdifrx);
+
+	ucontrol->value.iec958.status[0] = spdifrx->ub[0];
+	ucontrol->value.iec958.status[1] = spdifrx->ub[1];
+	ucontrol->value.iec958.status[2] = spdifrx->ub[2];
+	ucontrol->value.iec958.status[3] = spdifrx->ub[3];
+	ucontrol->value.iec958.status[4] = spdifrx->ub[4];
+
+	return 0;
+}
+
+static struct snd_kcontrol_new stm32_spdifrx_iec_ctrls[] = {
+	/* Channel status control */
+	{
+		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
+		.name = SNDRV_CTL_NAME_IEC958("", CAPTURE, DEFAULT),
+		.access = SNDRV_CTL_ELEM_ACCESS_READ |
+			  SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+		.info = stm32_spdifrx_info,
+		.get = stm32_spdifrx_capture_get,
+	},
+	/* User bits control */
+	{
+		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
+		.name = "IEC958 User Bit Capture Default",
+		.access = SNDRV_CTL_ELEM_ACCESS_READ |
+			  SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+		.info = stm32_spdifrx_ub_info,
+		.get = stm32_spdif_user_bits_get,
+	},
+};
+
+static struct snd_kcontrol_new stm32_spdifrx_ctrls[] = {
+	SOC_ENUM("SPDIFRX input", ctrl_enum_input),
+	SOC_ENUM("SPDIFRX CS channel", ctrl_enum_cs_channel),
+};
+
+static int stm32_spdifrx_dai_register_ctrls(struct snd_soc_dai *cpu_dai)
+{
+	int ret;
+
+	ret = snd_soc_add_dai_controls(cpu_dai, stm32_spdifrx_iec_ctrls,
+				       ARRAY_SIZE(stm32_spdifrx_iec_ctrls));
+	if (ret < 0)
+		return ret;
+
+	return snd_soc_add_component_controls(cpu_dai->component,
+					      stm32_spdifrx_ctrls,
+					      ARRAY_SIZE(stm32_spdifrx_ctrls));
+}
+
+static int stm32_spdifrx_dai_probe(struct snd_soc_dai *cpu_dai)
+{
+	struct stm32_spdifrx_data *spdifrx = dev_get_drvdata(cpu_dai->dev);
+
+	spdifrx->dma_params.addr = (dma_addr_t)(spdifrx->phys_addr +
+				   STM32_SPDIFRX_DR);
+	spdifrx->dma_params.maxburst = 1;
+
+	snd_soc_dai_init_dma_data(cpu_dai, NULL, &spdifrx->dma_params);
+
+	return stm32_spdifrx_dai_register_ctrls(cpu_dai);
+}
+
+static bool stm32_spdifrx_readable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case STM32_SPDIFRX_CR:
+	case STM32_SPDIFRX_IMR:
+	case STM32_SPDIFRX_SR:
+	case STM32_SPDIFRX_IFCR:
+	case STM32_SPDIFRX_DR:
+	case STM32_SPDIFRX_CSR:
+	case STM32_SPDIFRX_DIR:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool stm32_spdifrx_volatile_reg(struct device *dev, unsigned int reg)
+{
+	if (reg == STM32_SPDIFRX_DR)
+		return true;
+
+	return false;
+}
+
+static bool stm32_spdifrx_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case STM32_SPDIFRX_CR:
+	case STM32_SPDIFRX_IMR:
+	case STM32_SPDIFRX_IFCR:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static const struct regmap_config stm32_h7_spdifrx_regmap_conf = {
+	.reg_bits = 32,
+	.reg_stride = 4,
+	.val_bits = 32,
+	.max_register = STM32_SPDIFRX_DIR,
+	.readable_reg = stm32_spdifrx_readable_reg,
+	.volatile_reg = stm32_spdifrx_volatile_reg,
+	.writeable_reg = stm32_spdifrx_writeable_reg,
+	.fast_io = true,
+};
+
+static irqreturn_t stm32_spdifrx_isr(int irq, void *devid)
+{
+	struct stm32_spdifrx_data *spdifrx = (struct stm32_spdifrx_data *)devid;
+	struct snd_pcm_substream *substream = spdifrx->substream;
+	struct platform_device *pdev = spdifrx->pdev;
+	unsigned int cr, mask, sr, imr;
+	unsigned int flags;
+	int err = 0, err_xrun = 0;
+
+	regmap_read(spdifrx->regmap, STM32_SPDIFRX_SR, &sr);
+	regmap_read(spdifrx->regmap, STM32_SPDIFRX_IMR, &imr);
+
+	mask = imr & SPDIFRX_XIMR_MASK;
+	/* SERR, TERR, FERR IRQs are generated if IFEIE is set */
+	if (mask & SPDIFRX_IMR_IFEIE)
+		mask |= (SPDIFRX_IMR_IFEIE << 1) | (SPDIFRX_IMR_IFEIE << 2);
+
+	flags = sr & mask;
+	if (!flags) {
+		dev_err(&pdev->dev, "Unexpected IRQ. rflags=%#x, imr=%#x\n",
+			sr, imr);
+		return IRQ_NONE;
+	}
+
+	/* Clear IRQs */
+	regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IFCR,
+			   SPDIFRX_XIFCR_MASK, flags);
+
+	if (flags & SPDIFRX_SR_PERR) {
+		dev_dbg(&pdev->dev, "Parity error\n");
+		err_xrun = 1;
+	}
+
+	if (flags & SPDIFRX_SR_OVR) {
+		dev_dbg(&pdev->dev, "Overrun error\n");
+		err_xrun = 1;
+	}
+
+	if (flags & SPDIFRX_SR_SBD)
+		dev_dbg(&pdev->dev, "Synchronization block detected\n");
+
+	if (flags & SPDIFRX_SR_SYNCD) {
+		dev_dbg(&pdev->dev, "Synchronization done\n");
+
+		/* Enable spdifrx */
+		cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_ENABLE);
+		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
+				   SPDIFRX_CR_SPDIFEN_MASK, cr);
+	}
+
+	if (flags & SPDIFRX_SR_FERR) {
+		dev_dbg(&pdev->dev, "Frame error\n");
+		err = 1;
+	}
+
+	if (flags & SPDIFRX_SR_SERR) {
+		dev_dbg(&pdev->dev, "Synchronization error\n");
+		err = 1;
+	}
+
+	if (flags & SPDIFRX_SR_TERR) {
+		dev_dbg(&pdev->dev, "Timeout error\n");
+		err = 1;
+	}
+
+	if (err) {
+		/* SPDIFRX in STATE_STOP. Disable SPDIFRX to clear errors */
+		cr = SPDIFRX_CR_SPDIFENSET(SPDIFRX_SPDIFEN_DISABLE);
+		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
+				   SPDIFRX_CR_SPDIFEN_MASK, cr);
+
+		if (substream)
+			snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED);
+
+		return IRQ_HANDLED;
+	}
+
+	if (err_xrun && substream)
+		snd_pcm_stop_xrun(substream);
+
+	return IRQ_HANDLED;
+}
+
+static int stm32_spdifrx_startup(struct snd_pcm_substream *substream,
+				 struct snd_soc_dai *cpu_dai)
+{
+	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
+	int ret;
+
+	spdifrx->substream = substream;
+
+	ret = clk_prepare_enable(spdifrx->kclk);
+	if (ret)
+		dev_err(&spdifrx->pdev->dev, "Enable kclk failed: %d\n", ret);
+
+	return ret;
+}
+
+static int stm32_spdifrx_hw_params(struct snd_pcm_substream *substream,
+				   struct snd_pcm_hw_params *params,
+				   struct snd_soc_dai *cpu_dai)
+{
+	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
+	int data_size = params_width(params);
+	int fmt;
+
+	switch (data_size) {
+	case 16:
+		fmt = SPDIFRX_DRFMT_PACKED;
+		spdifrx->dma_params.addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+		break;
+	case 32:
+		fmt = SPDIFRX_DRFMT_LEFT;
+		spdifrx->dma_params.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+		break;
+	default:
+		dev_err(&spdifrx->pdev->dev, "Unexpected data format\n");
+		return -EINVAL;
+	}
+
+	snd_soc_dai_init_dma_data(cpu_dai, NULL, &spdifrx->dma_params);
+
+	return regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
+				  SPDIFRX_CR_DRFMT_MASK,
+				  SPDIFRX_CR_DRFMTSET(fmt));
+}
+
+static int stm32_spdifrx_trigger(struct snd_pcm_substream *substream, int cmd,
+				 struct snd_soc_dai *cpu_dai)
+{
+	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
+	int ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_IMR,
+				   SPDIFRX_IMR_OVRIE, SPDIFRX_IMR_OVRIE);
+
+		regmap_update_bits(spdifrx->regmap, STM32_SPDIFRX_CR,
+				   SPDIFRX_CR_RXDMAEN, SPDIFRX_CR_RXDMAEN);
+
+		ret = stm32_spdifrx_start_sync(spdifrx);
+		break;
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+	case SNDRV_PCM_TRIGGER_STOP:
+		stm32_spdifrx_stop(spdifrx);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return ret;
+}
+
+static void stm32_spdifrx_shutdown(struct snd_pcm_substream *substream,
+				   struct snd_soc_dai *cpu_dai)
+{
+	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
+
+	spdifrx->substream = NULL;
+	clk_disable_unprepare(spdifrx->kclk);
+}
+
+static const struct snd_soc_dai_ops stm32_spdifrx_pcm_dai_ops = {
+	.startup	= stm32_spdifrx_startup,
+	.hw_params	= stm32_spdifrx_hw_params,
+	.trigger	= stm32_spdifrx_trigger,
+	.shutdown	= stm32_spdifrx_shutdown,
+};
+
+static struct snd_soc_dai_driver stm32_spdifrx_dai[] = {
+	{
+		.name = "spdifrx-capture-cpu-dai",
+		.probe = stm32_spdifrx_dai_probe,
+		.capture = {
+			.stream_name = "CPU-Capture",
+			.channels_min = 1,
+			.channels_max = 2,
+			.rates = SNDRV_PCM_RATE_8000_192000,
+			.formats = SNDRV_PCM_FMTBIT_S32_LE |
+				   SNDRV_PCM_FMTBIT_S16_LE,
+		},
+		.ops = &stm32_spdifrx_pcm_dai_ops,
+	}
+};
+
+static const struct snd_pcm_hardware stm32_spdifrx_pcm_hw = {
+	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP,
+	.buffer_bytes_max = 8 * PAGE_SIZE,
+	.period_bytes_max = 2048, /* MDMA constraint */
+	.periods_min = 2,
+	.periods_max = 8,
+};
+
+static const struct snd_soc_component_driver stm32_spdifrx_component = {
+	.name = "stm32-spdifrx",
+};
+
+static const struct snd_dmaengine_pcm_config stm32_spdifrx_pcm_config = {
+	.pcm_hardware = &stm32_spdifrx_pcm_hw,
+	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
+};
+
+static const struct of_device_id stm32_spdifrx_ids[] = {
+	{
+		.compatible = "st,stm32h7-spdifrx",
+		.data = &stm32_h7_spdifrx_regmap_conf
+	},
+	{}
+};
+
+static int stm_spdifrx_parse_of(struct platform_device *pdev,
+				struct stm32_spdifrx_data *spdifrx)
+{
+	struct device_node *np = pdev->dev.of_node;
+	const struct of_device_id *of_id;
+	struct resource *res;
+
+	if (!np)
+		return -ENODEV;
+
+	of_id = of_match_device(stm32_spdifrx_ids, &pdev->dev);
+	if (of_id)
+		spdifrx->regmap_conf =
+			(const struct regmap_config *)of_id->data;
+	else
+		return -EINVAL;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	spdifrx->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(spdifrx->base))
+		return PTR_ERR(spdifrx->base);
+
+	spdifrx->phys_addr = res->start;
+
+	spdifrx->kclk = devm_clk_get(&pdev->dev, "kclk");
+	if (IS_ERR(spdifrx->kclk)) {
+		dev_err(&pdev->dev, "Could not get kclk\n");
+		return PTR_ERR(spdifrx->kclk);
+	}
+
+	spdifrx->irq = platform_get_irq(pdev, 0);
+	if (spdifrx->irq < 0) {
+		dev_err(&pdev->dev, "No irq for node %s\n", pdev->name);
+		return spdifrx->irq;
+	}
+
+	return 0;
+}
+
+static int stm32_spdifrx_probe(struct platform_device *pdev)
+{
+	struct stm32_spdifrx_data *spdifrx;
+	struct reset_control *rst;
+	const struct snd_dmaengine_pcm_config *pcm_config = NULL;
+	int ret;
+
+	spdifrx = devm_kzalloc(&pdev->dev, sizeof(*spdifrx), GFP_KERNEL);
+	if (!spdifrx)
+		return -ENOMEM;
+
+	spdifrx->pdev = pdev;
+	init_completion(&spdifrx->cs_completion);
+	spin_lock_init(&spdifrx->lock);
+
+	platform_set_drvdata(pdev, spdifrx);
+
+	ret = stm_spdifrx_parse_of(pdev, spdifrx);
+	if (ret)
+		return ret;
+
+	spdifrx->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "kclk",
+						    spdifrx->base,
+						    spdifrx->regmap_conf);
+	if (IS_ERR(spdifrx->regmap)) {
+		dev_err(&pdev->dev, "Regmap init failed\n");
+		return PTR_ERR(spdifrx->regmap);
+	}
+
+	ret = devm_request_irq(&pdev->dev, spdifrx->irq, stm32_spdifrx_isr, 0,
+			       dev_name(&pdev->dev), spdifrx);
+	if (ret) {
+		dev_err(&pdev->dev, "IRQ request returned %d\n", ret);
+		return ret;
+	}
+
+	rst = devm_reset_control_get(&pdev->dev, NULL);
+	if (!IS_ERR(rst)) {
+		reset_control_assert(rst);
+		udelay(2);
+		reset_control_deassert(rst);
+	}
+
+	ret = devm_snd_soc_register_component(&pdev->dev,
+					      &stm32_spdifrx_component,
+					      stm32_spdifrx_dai,
+					      ARRAY_SIZE(stm32_spdifrx_dai));
+	if (ret)
+		return ret;
+
+	ret = stm32_spdifrx_dma_ctrl_register(&pdev->dev, spdifrx);
+	if (ret)
+		goto error;
+
+	pcm_config = &stm32_spdifrx_pcm_config;
+	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, pcm_config, 0);
+	if (ret) {
+		dev_err(&pdev->dev, "PCM DMA register returned %d\n", ret);
+		goto error;
+	}
+
+	return 0;
+
+error:
+	if (spdifrx->ctrl_chan)
+		dma_release_channel(spdifrx->ctrl_chan);
+	if (spdifrx->dmab)
+		snd_dma_free_pages(spdifrx->dmab);
+
+	return ret;
+}
+
+static int stm32_spdifrx_remove(struct platform_device *pdev)
+{
+	struct stm32_spdifrx_data *spdifrx = platform_get_drvdata(pdev);
+
+	if (spdifrx->ctrl_chan)
+		dma_release_channel(spdifrx->ctrl_chan);
+
+	if (spdifrx->dmab)
+		snd_dma_free_pages(spdifrx->dmab);
+
+	return 0;
+}
+
+MODULE_DEVICE_TABLE(of, stm32_spdifrx_ids);
+
+static struct platform_driver stm32_spdifrx_driver = {
+	.driver = {
+		.name = "st,stm32-spdifrx",
+		.of_match_table = stm32_spdifrx_ids,
+	},
+	.probe = stm32_spdifrx_probe,
+	.remove = stm32_spdifrx_remove,
+};
+
+module_platform_driver(stm32_spdifrx_driver);
+
+MODULE_DESCRIPTION("STM32 Soc spdifrx Interface");
+MODULE_AUTHOR("Olivier Moysan, <olivier.moysan@st.com>");
+MODULE_ALIAS("platform:stm32-spdifrx");
+MODULE_LICENSE("GPL v2");