Merge tag 'sound-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound

Pull sound updates from Takashi Iwai:
 "The major changes in the core API side in this cycle are the still
  on-going ASoC componentization works. Other than that, only few small
  changes such as 20bit PCM format support are found.

  Meanwhile the rest majority of changes are for ASoC drivers:

   - Large cleanups of some of the TI CODEC drivers

   - Continued work on Intel ASoC stuff for new quirks, ACPI GPIO
     handling, Kconfigs and lots of cleanups

   - Refactoring of the Freescale SSI driver, as preliminary work for
     the upcoming changes

   - Work on ST DFSDM driver, including the required IIO patches

   - New drivers for Allwinner A83T, Maxim MAX89373, SocioNext UiniPhier
     EVEA Tempo Semiconductor TSCS42xx and TI PCM816x, TAS5722 and
     TAS6424 devices

   - Removal of dead codes for SN95031 and board drivers

  Last but not least, a few HD-audio and USB-audio quirks are included
  as usual, too"

* tag 'sound-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (303 commits)
  ALSA: hda - Reduce the suspend time consumption for ALC256
  ASoC: use seq_file to dump the contents of dai_list,platform_list and codec_list
  ASoC: soc-core: add missing EXPORT_SYMBOL_GPL() for snd_soc_rtdcom_lookup
  IIO: ADC: stm32-dfsdm: remove unused variable again
  ASoC: bcm2835: fix hw_params error when device is in prepared state
  ASoC: mxs-sgtl5000: Do not print error on probe deferral
  ASoC: sgtl5000: Do not print error on probe deferral
  ASoC: Intel: remove select on non-existing SND_SOC_INTEL_COMMON
  ALSA: usb-audio: Support changing input on Sound Blaster E1
  ASoC: Intel: remove second duplicated assignment to pointer 'res'
  ALSA: hda/realtek - update ALC215 depop optimize
  ALSA: hda/realtek - Support headset mode for ALC215/ALC285/ALC289
  ALSA: pcm: Fix trailing semicolon
  ASoC: add Component level .read/.write
  ASoC: cx20442: fix regression by adding back .read/.write
  ASoC: uda1380: fix regression by adding back .read/.write
  ASoC: tlv320dac33: fix regression by adding back .read/.write
  ALSA: hda - Use IS_REACHABLE() for dependency on input
  IIO: ADC: stm32-dfsdm: fix static check warning
  IIO: ADC: stm32-dfsdm: code optimization
  ...

13 files changed, 2250 insertions, 13 deletions

diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c
index 9d49a1acebe3..78db97687f26 100644
--- a/drivers/acpi/utils.c
+++ b/drivers/acpi/utils.c
@@ -737,16 +737,17 @@ bool acpi_dev_found(const char *hid)
 }
 EXPORT_SYMBOL(acpi_dev_found);
 
-struct acpi_dev_present_info {
+struct acpi_dev_match_info {
+	const char *dev_name;
 	struct acpi_device_id hid[2];
 	const char *uid;
 	s64 hrv;
 };
 
-static int acpi_dev_present_cb(struct device *dev, void *data)
+static int acpi_dev_match_cb(struct device *dev, void *data)
 {
 	struct acpi_device *adev = to_acpi_device(dev);
-	struct acpi_dev_present_info *match = data;
+	struct acpi_dev_match_info *match = data;
 	unsigned long long hrv;
 	acpi_status status;
 
@@ -757,6 +758,8 @@ static int acpi_dev_present_cb(struct device *dev, void *data)
 	    strcmp(adev->pnp.unique_id, match->uid)))
 		return 0;
 
+	match->dev_name = acpi_dev_name(adev);
+
 	if (match->hrv == -1)
 		return 1;
 
@@ -789,20 +792,44 @@ static int acpi_dev_present_cb(struct device *dev, void *data)
  */
 bool acpi_dev_present(const char *hid, const char *uid, s64 hrv)
 {
-	struct acpi_dev_present_info match = {};
+	struct acpi_dev_match_info match = {};
 	struct device *dev;
 
 	strlcpy(match.hid[0].id, hid, sizeof(match.hid[0].id));
 	match.uid = uid;
 	match.hrv = hrv;
 
-	dev = bus_find_device(&acpi_bus_type, NULL, &match,
-			      acpi_dev_present_cb);
-
+	dev = bus_find_device(&acpi_bus_type, NULL, &match, acpi_dev_match_cb);
 	return !!dev;
 }
 EXPORT_SYMBOL(acpi_dev_present);
 
+/**
+ * acpi_dev_get_first_match_name - Return name of first match of ACPI device
+ * @hid: Hardware ID of the device.
+ * @uid: Unique ID of the device, pass NULL to not check _UID
+ * @hrv: Hardware Revision of the device, pass -1 to not check _HRV
+ *
+ * Return device name if a matching device was present
+ * at the moment of invocation, or NULL otherwise.
+ *
+ * See additional information in acpi_dev_present() as well.
+ */
+const char *
+acpi_dev_get_first_match_name(const char *hid, const char *uid, s64 hrv)
+{
+	struct acpi_dev_match_info match = {};
+	struct device *dev;
+
+	strlcpy(match.hid[0].id, hid, sizeof(match.hid[0].id));
+	match.uid = uid;
+	match.hrv = hrv;
+
+	dev = bus_find_device(&acpi_bus_type, NULL, &match, acpi_dev_match_cb);
+	return dev ? match.dev_name : NULL;
+}
+EXPORT_SYMBOL(acpi_dev_get_first_match_name);
+
 /*
  * acpi_backlight= handling, this is done here rather then in video_detect.c
  * because __setup cannot be used in modules.
diff --git a/drivers/gpio/gpio-merrifield.c b/drivers/gpio/gpio-merrifield.c
index dd67a31ac337..c38624ea0251 100644
--- a/drivers/gpio/gpio-merrifield.c
+++ b/drivers/gpio/gpio-merrifield.c
@@ -9,6 +9,7 @@
  * published by the Free Software Foundation.
  */
 
+#include <linux/acpi.h>
 #include <linux/bitops.h>
 #include <linux/gpio/driver.h>
 #include <linux/init.h>
@@ -380,9 +381,16 @@ static void mrfld_irq_init_hw(struct mrfld_gpio *priv)
 	}
 }
 
+static const char *mrfld_gpio_get_pinctrl_dev_name(void)
+{
+	const char *dev_name = acpi_dev_get_first_match_name("INTC1002", NULL, -1);
+	return dev_name ? dev_name : "pinctrl-merrifield";
+}
+
 static int mrfld_gpio_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
 	const struct mrfld_gpio_pinrange *range;
+	const char *pinctrl_dev_name;
 	struct mrfld_gpio *priv;
 	u32 gpio_base, irq_base;
 	void __iomem *base;
@@ -439,10 +447,11 @@ static int mrfld_gpio_probe(struct pci_dev *pdev, const struct pci_device_id *id
 		return retval;
 	}
 
+	pinctrl_dev_name = mrfld_gpio_get_pinctrl_dev_name();
 	for (i = 0; i < ARRAY_SIZE(mrfld_gpio_ranges); i++) {
 		range = &mrfld_gpio_ranges[i];
 		retval = gpiochip_add_pin_range(&priv->chip,
-						"pinctrl-merrifield",
+						pinctrl_dev_name,
 						range->gpio_base,
 						range->pin_base,
 						range->npins);
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index ef86296b8b0d..39e3b345a6c8 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -629,6 +629,18 @@ config SPEAR_ADC
 	  To compile this driver as a module, choose M here: the
 	  module will be called spear_adc.
 
+config SD_ADC_MODULATOR
+	tristate "Generic sigma delta modulator"
+	depends on OF
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	help
+	  Select this option to enables sigma delta modulator. This driver can
+	  support generic sigma delta modulators.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called sd_adc_modulator.
+
 config STM32_ADC_CORE
 	tristate "STMicroelectronics STM32 adc core"
 	depends on ARCH_STM32 || COMPILE_TEST
@@ -656,6 +668,31 @@ config STM32_ADC
 	  This driver can also be built as a module.  If so, the module
 	  will be called stm32-adc.
 
+config STM32_DFSDM_CORE
+	tristate "STMicroelectronics STM32 DFSDM core"
+	depends on (ARCH_STM32 && OF) || COMPILE_TEST
+	select REGMAP
+	select REGMAP_MMIO
+	help
+	  Select this option to enable the  driver for STMicroelectronics
+	  STM32 digital filter for sigma delta converter.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called stm32-dfsdm-core.
+
+config STM32_DFSDM_ADC
+	tristate "STMicroelectronics STM32 dfsdm adc"
+	depends on (ARCH_STM32 && OF) || COMPILE_TEST
+	select STM32_DFSDM_CORE
+	select REGMAP_MMIO
+	select IIO_BUFFER_HW_CONSUMER
+	help
+	  Select this option to support ADCSigma delta modulator for
+	  STMicroelectronics STM32 digital filter for sigma delta converter.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called stm32-dfsdm-adc.
+
 config STX104
 	tristate "Apex Embedded Systems STX104 driver"
 	depends on PC104 && X86 && ISA_BUS_API
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 9572c1090f35..28a9423997f3 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -64,6 +64,8 @@ obj-$(CONFIG_STX104) += stx104.o
 obj-$(CONFIG_SUN4I_GPADC) += sun4i-gpadc-iio.o
 obj-$(CONFIG_STM32_ADC_CORE) += stm32-adc-core.o
 obj-$(CONFIG_STM32_ADC) += stm32-adc.o
+obj-$(CONFIG_STM32_DFSDM_CORE) += stm32-dfsdm-core.o
+obj-$(CONFIG_STM32_DFSDM_ADC) += stm32-dfsdm-adc.o
 obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
 obj-$(CONFIG_TI_ADC0832) += ti-adc0832.o
 obj-$(CONFIG_TI_ADC084S021) += ti-adc084s021.o
@@ -82,3 +84,4 @@ obj-$(CONFIG_VF610_ADC) += vf610_adc.o
 obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o
 xilinx-xadc-y := xilinx-xadc-core.o xilinx-xadc-events.o
 obj-$(CONFIG_XILINX_XADC) += xilinx-xadc.o
+obj-$(CONFIG_SD_ADC_MODULATOR) += sd_adc_modulator.o
diff --git a/drivers/iio/adc/sd_adc_modulator.c b/drivers/iio/adc/sd_adc_modulator.c
new file mode 100644
index 000000000000..560d8c7d9d86
--- /dev/null
+++ b/drivers/iio/adc/sd_adc_modulator.c
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Generic sigma delta modulator driver
+ *
+ * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
+ * Author: Arnaud Pouliquen <arnaud.pouliquen@st.com>.
+ */
+
+#include <linux/iio/iio.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+
+static const struct iio_info iio_sd_mod_iio_info;
+
+static const struct iio_chan_spec iio_sd_mod_ch = {
+	.type = IIO_VOLTAGE,
+	.indexed = 1,
+	.scan_type = {
+		.sign = 'u',
+		.realbits = 1,
+		.shift = 0,
+	},
+};
+
+static int iio_sd_mod_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct iio_dev *iio;
+
+	iio = devm_iio_device_alloc(dev, 0);
+	if (!iio)
+		return -ENOMEM;
+
+	iio->dev.parent = dev;
+	iio->dev.of_node = dev->of_node;
+	iio->name = dev_name(dev);
+	iio->info = &iio_sd_mod_iio_info;
+	iio->modes = INDIO_BUFFER_HARDWARE;
+
+	iio->num_channels = 1;
+	iio->channels = &iio_sd_mod_ch;
+
+	platform_set_drvdata(pdev, iio);
+
+	return devm_iio_device_register(&pdev->dev, iio);
+}
+
+static const struct of_device_id sd_adc_of_match[] = {
+	{ .compatible = "sd-modulator" },
+	{ .compatible = "ads1201" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, sd_adc_of_match);
+
+static struct platform_driver iio_sd_mod_adc = {
+	.driver = {
+		.name = "iio_sd_adc_mod",
+		.of_match_table = of_match_ptr(sd_adc_of_match),
+	},
+	.probe = iio_sd_mod_probe,
+};
+
+module_platform_driver(iio_sd_mod_adc);
+
+MODULE_DESCRIPTION("Basic sigma delta modulator");
+MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c
new file mode 100644
index 000000000000..daa026d6a94f
--- /dev/null
+++ b/drivers/iio/adc/stm32-dfsdm-adc.c
@@ -0,0 +1,1205 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This file is the ADC part of the STM32 DFSDM driver
+ *
+ * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
+ * Author: Arnaud Pouliquen <arnaud.pouliquen@st.com>.
+ */
+
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/hw-consumer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include "stm32-dfsdm.h"
+
+#define DFSDM_DMA_BUFFER_SIZE (4 * PAGE_SIZE)
+
+/* Conversion timeout */
+#define DFSDM_TIMEOUT_US 100000
+#define DFSDM_TIMEOUT (msecs_to_jiffies(DFSDM_TIMEOUT_US / 1000))
+
+/* Oversampling attribute default */
+#define DFSDM_DEFAULT_OVERSAMPLING  100
+
+/* Oversampling max values */
+#define DFSDM_MAX_INT_OVERSAMPLING 256
+#define DFSDM_MAX_FL_OVERSAMPLING 1024
+
+/* Max sample resolutions */
+#define DFSDM_MAX_RES BIT(31)
+#define DFSDM_DATA_RES BIT(23)
+
+enum sd_converter_type {
+	DFSDM_AUDIO,
+	DFSDM_IIO,
+};
+
+struct stm32_dfsdm_dev_data {
+	int type;
+	int (*init)(struct iio_dev *indio_dev);
+	unsigned int num_channels;
+	const struct regmap_config *regmap_cfg;
+};
+
+struct stm32_dfsdm_adc {
+	struct stm32_dfsdm *dfsdm;
+	const struct stm32_dfsdm_dev_data *dev_data;
+	unsigned int fl_id;
+	unsigned int ch_id;
+
+	/* ADC specific */
+	unsigned int oversamp;
+	struct iio_hw_consumer *hwc;
+	struct completion completion;
+	u32 *buffer;
+
+	/* Audio specific */
+	unsigned int spi_freq;  /* SPI bus clock frequency */
+	unsigned int sample_freq; /* Sample frequency after filter decimation */
+	int (*cb)(const void *data, size_t size, void *cb_priv);
+	void *cb_priv;
+
+	/* DMA */
+	u8 *rx_buf;
+	unsigned int bufi; /* Buffer current position */
+	unsigned int buf_sz; /* Buffer size */
+	struct dma_chan	*dma_chan;
+	dma_addr_t dma_buf;
+};
+
+struct stm32_dfsdm_str2field {
+	const char	*name;
+	unsigned int	val;
+};
+
+/* DFSDM channel serial interface type */
+static const struct stm32_dfsdm_str2field stm32_dfsdm_chan_type[] = {
+	{ "SPI_R", 0 }, /* SPI with data on rising edge */
+	{ "SPI_F", 1 }, /* SPI with data on falling edge */
+	{ "MANCH_R", 2 }, /* Manchester codec, rising edge = logic 0 */
+	{ "MANCH_F", 3 }, /* Manchester codec, falling edge = logic 1 */
+	{},
+};
+
+/* DFSDM channel clock source */
+static const struct stm32_dfsdm_str2field stm32_dfsdm_chan_src[] = {
+	/* External SPI clock (CLKIN x) */
+	{ "CLKIN", DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL },
+	/* Internal SPI clock (CLKOUT) */
+	{ "CLKOUT", DFSDM_CHANNEL_SPI_CLOCK_INTERNAL },
+	/* Internal SPI clock divided by 2 (falling edge) */
+	{ "CLKOUT_F", DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING },
+	/* Internal SPI clock divided by 2 (falling edge) */
+	{ "CLKOUT_R", DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING },
+	{},
+};
+
+static int stm32_dfsdm_str2val(const char *str,
+			       const struct stm32_dfsdm_str2field *list)
+{
+	const struct stm32_dfsdm_str2field *p = list;
+
+	for (p = list; p && p->name; p++)
+		if (!strcmp(p->name, str))
+			return p->val;
+
+	return -EINVAL;
+}
+
+static int stm32_dfsdm_set_osrs(struct stm32_dfsdm_filter *fl,
+				unsigned int fast, unsigned int oversamp)
+{
+	unsigned int i, d, fosr, iosr;
+	u64 res;
+	s64 delta;
+	unsigned int m = 1;	/* multiplication factor */
+	unsigned int p = fl->ford;	/* filter order (ford) */
+
+	pr_debug("%s: Requested oversampling: %d\n",  __func__, oversamp);
+	/*
+	 * This function tries to compute filter oversampling and integrator
+	 * oversampling, base on oversampling ratio requested by user.
+	 *
+	 * Decimation d depends on the filter order and the oversampling ratios.
+	 * ford: filter order
+	 * fosr: filter over sampling ratio
+	 * iosr: integrator over sampling ratio
+	 */
+	if (fl->ford == DFSDM_FASTSINC_ORDER) {
+		m = 2;
+		p = 2;
+	}
+
+	/*
+	 * Look for filter and integrator oversampling ratios which allows
+	 * to reach 24 bits data output resolution.
+	 * Leave as soon as if exact resolution if reached.
+	 * Otherwise the higher resolution below 32 bits is kept.
+	 */
+	for (fosr = 1; fosr <= DFSDM_MAX_FL_OVERSAMPLING; fosr++) {
+		for (iosr = 1; iosr <= DFSDM_MAX_INT_OVERSAMPLING; iosr++) {
+			if (fast)
+				d = fosr * iosr;
+			else if (fl->ford == DFSDM_FASTSINC_ORDER)
+				d = fosr * (iosr + 3) + 2;
+			else
+				d = fosr * (iosr - 1 + p) + p;
+
+			if (d > oversamp)
+				break;
+			else if (d != oversamp)
+				continue;
+			/*
+			 * Check resolution (limited to signed 32 bits)
+			 *   res <= 2^31
+			 * Sincx filters:
+			 *   res = m * fosr^p x iosr (with m=1, p=ford)
+			 * FastSinc filter
+			 *   res = m * fosr^p x iosr (with m=2, p=2)
+			 */
+			res = fosr;
+			for (i = p - 1; i > 0; i--) {
+				res = res * (u64)fosr;
+				if (res > DFSDM_MAX_RES)
+					break;
+			}
+			if (res > DFSDM_MAX_RES)
+				continue;
+			res = res * (u64)m * (u64)iosr;
+			if (res > DFSDM_MAX_RES)
+				continue;
+
+			delta = res - DFSDM_DATA_RES;
+
+			if (res >= fl->res) {
+				fl->res = res;
+				fl->fosr = fosr;
+				fl->iosr = iosr;
+				fl->fast = fast;
+				pr_debug("%s: fosr = %d, iosr = %d\n",
+					 __func__, fl->fosr, fl->iosr);
+			}
+
+			if (!delta)
+				return 0;
+		}
+	}
+
+	if (!fl->fosr)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int stm32_dfsdm_start_channel(struct stm32_dfsdm *dfsdm,
+				     unsigned int ch_id)
+{
+	return regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(ch_id),
+				  DFSDM_CHCFGR1_CHEN_MASK,
+				  DFSDM_CHCFGR1_CHEN(1));
+}
+
+static void stm32_dfsdm_stop_channel(struct stm32_dfsdm *dfsdm,
+				     unsigned int ch_id)
+{
+	regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(ch_id),
+			   DFSDM_CHCFGR1_CHEN_MASK, DFSDM_CHCFGR1_CHEN(0));
+}
+
+static int stm32_dfsdm_chan_configure(struct stm32_dfsdm *dfsdm,
+				      struct stm32_dfsdm_channel *ch)
+{
+	unsigned int id = ch->id;
+	struct regmap *regmap = dfsdm->regmap;
+	int ret;
+
+	ret = regmap_update_bits(regmap, DFSDM_CHCFGR1(id),
+				 DFSDM_CHCFGR1_SITP_MASK,
+				 DFSDM_CHCFGR1_SITP(ch->type));
+	if (ret < 0)
+		return ret;
+	ret = regmap_update_bits(regmap, DFSDM_CHCFGR1(id),
+				 DFSDM_CHCFGR1_SPICKSEL_MASK,
+				 DFSDM_CHCFGR1_SPICKSEL(ch->src));
+	if (ret < 0)
+		return ret;
+	return regmap_update_bits(regmap, DFSDM_CHCFGR1(id),
+				  DFSDM_CHCFGR1_CHINSEL_MASK,
+				  DFSDM_CHCFGR1_CHINSEL(ch->alt_si));
+}
+
+static int stm32_dfsdm_start_filter(struct stm32_dfsdm *dfsdm,
+				    unsigned int fl_id)
+{
+	int ret;
+
+	/* Enable filter */
+	ret = regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id),
+				 DFSDM_CR1_DFEN_MASK, DFSDM_CR1_DFEN(1));
+	if (ret < 0)
+		return ret;
+
+	/* Start conversion */
+	return regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id),
+				  DFSDM_CR1_RSWSTART_MASK,
+				  DFSDM_CR1_RSWSTART(1));
+}
+
+static void stm32_dfsdm_stop_filter(struct stm32_dfsdm *dfsdm, unsigned int fl_id)
+{
+	/* Disable conversion */
+	regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id),
+			   DFSDM_CR1_DFEN_MASK, DFSDM_CR1_DFEN(0));
+}
+
+static int stm32_dfsdm_filter_configure(struct stm32_dfsdm *dfsdm,
+					unsigned int fl_id, unsigned int ch_id)
+{
+	struct regmap *regmap = dfsdm->regmap;
+	struct stm32_dfsdm_filter *fl = &dfsdm->fl_list[fl_id];
+	int ret;
+
+	/* Average integrator oversampling */
+	ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_IOSR_MASK,
+				 DFSDM_FCR_IOSR(fl->iosr - 1));
+	if (ret)
+		return ret;
+
+	/* Filter order and Oversampling */
+	ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_FOSR_MASK,
+				 DFSDM_FCR_FOSR(fl->fosr - 1));
+	if (ret)
+		return ret;
+
+	ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_FORD_MASK,
+				 DFSDM_FCR_FORD(fl->ford));
+	if (ret)
+		return ret;
+
+	/* No scan mode supported for the moment */
+	ret = regmap_update_bits(regmap, DFSDM_CR1(fl_id), DFSDM_CR1_RCH_MASK,
+				 DFSDM_CR1_RCH(ch_id));
+	if (ret)
+		return ret;
+
+	return regmap_update_bits(regmap, DFSDM_CR1(fl_id),
+				  DFSDM_CR1_RSYNC_MASK,
+				  DFSDM_CR1_RSYNC(fl->sync_mode));
+}
+
+static int stm32_dfsdm_channel_parse_of(struct stm32_dfsdm *dfsdm,
+					struct iio_dev *indio_dev,
+					struct iio_chan_spec *ch)
+{
+	struct stm32_dfsdm_channel *df_ch;
+	const char *of_str;
+	int chan_idx = ch->scan_index;
+	int ret, val;
+
+	ret = of_property_read_u32_index(indio_dev->dev.of_node,
+					 "st,adc-channels", chan_idx,
+					 &ch->channel);
+	if (ret < 0) {
+		dev_err(&indio_dev->dev,
+			" Error parsing 'st,adc-channels' for idx %d\n",
+			chan_idx);
+		return ret;
+	}
+	if (ch->channel >= dfsdm->num_chs) {
+		dev_err(&indio_dev->dev,
+			" Error bad channel number %d (max = %d)\n",
+			ch->channel, dfsdm->num_chs);
+		return -EINVAL;
+	}
+
+	ret = of_property_read_string_index(indio_dev->dev.of_node,
+					    "st,adc-channel-names", chan_idx,
+					    &ch->datasheet_name);
+	if (ret < 0) {
+		dev_err(&indio_dev->dev,
+			" Error parsing 'st,adc-channel-names' for idx %d\n",
+			chan_idx);
+		return ret;
+	}
+
+	df_ch =  &dfsdm->ch_list[ch->channel];
+	df_ch->id = ch->channel;
+
+	ret = of_property_read_string_index(indio_dev->dev.of_node,
+					    "st,adc-channel-types", chan_idx,
+					    &of_str);
+	if (!ret) {
+		val  = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_type);
+		if (val < 0)
+			return val;
+	} else {
+		val = 0;
+	}
+	df_ch->type = val;
+
+	ret = of_property_read_string_index(indio_dev->dev.of_node,
+					    "st,adc-channel-clk-src", chan_idx,
+					    &of_str);
+	if (!ret) {
+		val  = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_src);
+		if (val < 0)
+			return val;
+	} else {
+		val = 0;
+	}
+	df_ch->src = val;
+
+	ret = of_property_read_u32_index(indio_dev->dev.of_node,
+					 "st,adc-alt-channel", chan_idx,
+					 &df_ch->alt_si);
+	if (ret < 0)
+		df_ch->alt_si = 0;
+
+	return 0;
+}
+
+static ssize_t dfsdm_adc_audio_get_spiclk(struct iio_dev *indio_dev,
+					  uintptr_t priv,
+					  const struct iio_chan_spec *chan,
+					  char *buf)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", adc->spi_freq);
+}
+
+static ssize_t dfsdm_adc_audio_set_spiclk(struct iio_dev *indio_dev,
+					  uintptr_t priv,
+					  const struct iio_chan_spec *chan,
+					  const char *buf, size_t len)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id];
+	struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[adc->ch_id];
+	unsigned int sample_freq = adc->sample_freq;
+	unsigned int spi_freq;
+	int ret;
+
+	dev_err(&indio_dev->dev, "enter %s\n", __func__);
+	/* If DFSDM is master on SPI, SPI freq can not be updated */
+	if (ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL)
+		return -EPERM;
+
+	ret = kstrtoint(buf, 0, &spi_freq);
+	if (ret)
+		return ret;
+
+	if (!spi_freq)
+		return -EINVAL;
+
+	if (sample_freq) {
+		if (spi_freq % sample_freq)
+			dev_warn(&indio_dev->dev,
+				 "Sampling rate not accurate (%d)\n",
+				 spi_freq / (spi_freq / sample_freq));
+
+		ret = stm32_dfsdm_set_osrs(fl, 0, (spi_freq / sample_freq));
+		if (ret < 0) {
+			dev_err(&indio_dev->dev,
+				"No filter parameters that match!\n");
+			return ret;
+		}
+	}
+	adc->spi_freq = spi_freq;
+
+	return len;
+}
+
+static int stm32_dfsdm_start_conv(struct stm32_dfsdm_adc *adc, bool dma)
+{
+	struct regmap *regmap = adc->dfsdm->regmap;
+	int ret;
+	unsigned int dma_en = 0, cont_en = 0;
+
+	ret = stm32_dfsdm_start_channel(adc->dfsdm, adc->ch_id);
+	if (ret < 0)
+		return ret;
+
+	ret = stm32_dfsdm_filter_configure(adc->dfsdm, adc->fl_id,
+					   adc->ch_id);
+	if (ret < 0)
+		goto stop_channels;
+
+	if (dma) {
+		/* Enable DMA transfer*/
+		dma_en =  DFSDM_CR1_RDMAEN(1);
+		/* Enable conversion triggered by SPI clock*/
+		cont_en = DFSDM_CR1_RCONT(1);
+	}
+	/* Enable DMA transfer*/
+	ret = regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id),
+				 DFSDM_CR1_RDMAEN_MASK, dma_en);
+	if (ret < 0)
+		goto stop_channels;
+
+	/* Enable conversion triggered by SPI clock*/
+	ret = regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id),
+				 DFSDM_CR1_RCONT_MASK, cont_en);
+	if (ret < 0)
+		goto stop_channels;
+
+	ret = stm32_dfsdm_start_filter(adc->dfsdm, adc->fl_id);
+	if (ret < 0)
+		goto stop_channels;
+
+	return 0;
+
+stop_channels:
+	regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id),
+			   DFSDM_CR1_RDMAEN_MASK, 0);
+
+	regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id),
+			   DFSDM_CR1_RCONT_MASK, 0);
+	stm32_dfsdm_stop_channel(adc->dfsdm, adc->fl_id);
+
+	return ret;
+}
+
+static void stm32_dfsdm_stop_conv(struct stm32_dfsdm_adc *adc)
+{
+	struct regmap *regmap = adc->dfsdm->regmap;
+
+	stm32_dfsdm_stop_filter(adc->dfsdm, adc->fl_id);
+
+	/* Clean conversion options */
+	regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id),
+			   DFSDM_CR1_RDMAEN_MASK, 0);
+
+	regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id),
+			   DFSDM_CR1_RCONT_MASK, 0);
+
+	stm32_dfsdm_stop_channel(adc->dfsdm, adc->ch_id);
+}
+
+static int stm32_dfsdm_set_watermark(struct iio_dev *indio_dev,
+				     unsigned int val)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	unsigned int watermark = DFSDM_DMA_BUFFER_SIZE / 2;
+
+	/*
+	 * DMA cyclic transfers are used, buffer is split into two periods.
+	 * There should be :
+	 * - always one buffer (period) DMA is working on
+	 * - one buffer (period) driver pushed to ASoC side.
+	 */
+	watermark = min(watermark, val * (unsigned int)(sizeof(u32)));
+	adc->buf_sz = watermark * 2;
+
+	return 0;
+}
+
+static unsigned int stm32_dfsdm_adc_dma_residue(struct stm32_dfsdm_adc *adc)
+{
+	struct dma_tx_state state;
+	enum dma_status status;
+
+	status = dmaengine_tx_status(adc->dma_chan,
+				     adc->dma_chan->cookie,
+				     &state);
+	if (status == DMA_IN_PROGRESS) {
+		/* Residue is size in bytes from end of buffer */
+		unsigned int i = adc->buf_sz - state.residue;
+		unsigned int size;
+
+		/* Return available bytes */
+		if (i >= adc->bufi)
+			size = i - adc->bufi;
+		else
+			size = adc->buf_sz + i - adc->bufi;
+
+		return size;
+	}
+
+	return 0;
+}
+
+static void stm32_dfsdm_audio_dma_buffer_done(void *data)
+{
+	struct iio_dev *indio_dev = data;
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	int available = stm32_dfsdm_adc_dma_residue(adc);
+	size_t old_pos;
+
+	/*
+	 * FIXME: In Kernel interface does not support cyclic DMA buffer,and
+	 * offers only an interface to push data samples per samples.
+	 * For this reason IIO buffer interface is not used and interface is
+	 * bypassed using a private callback registered by ASoC.
+	 * This should be a temporary solution waiting a cyclic DMA engine
+	 * support in IIO.
+	 */
+
+	dev_dbg(&indio_dev->dev, "%s: pos = %d, available = %d\n", __func__,
+		adc->bufi, available);
+	old_pos = adc->bufi;
+
+	while (available >= indio_dev->scan_bytes) {
+		u32 *buffer = (u32 *)&adc->rx_buf[adc->bufi];
+
+		/* Mask 8 LSB that contains the channel ID */
+		*buffer = (*buffer & 0xFFFFFF00) << 8;
+		available -= indio_dev->scan_bytes;
+		adc->bufi += indio_dev->scan_bytes;
+		if (adc->bufi >= adc->buf_sz) {
+			if (adc->cb)
+				adc->cb(&adc->rx_buf[old_pos],
+					 adc->buf_sz - old_pos, adc->cb_priv);
+			adc->bufi = 0;
+			old_pos = 0;
+		}
+	}
+	if (adc->cb)
+		adc->cb(&adc->rx_buf[old_pos], adc->bufi - old_pos,
+			adc->cb_priv);
+}
+
+static int stm32_dfsdm_adc_dma_start(struct iio_dev *indio_dev)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	struct dma_async_tx_descriptor *desc;
+	dma_cookie_t cookie;
+	int ret;
+
+	if (!adc->dma_chan)
+		return -EINVAL;
+
+	dev_dbg(&indio_dev->dev, "%s size=%d watermark=%d\n", __func__,
+		adc->buf_sz, adc->buf_sz / 2);
+
+	/* Prepare a DMA cyclic transaction */
+	desc = dmaengine_prep_dma_cyclic(adc->dma_chan,
+					 adc->dma_buf,
+					 adc->buf_sz, adc->buf_sz / 2,
+					 DMA_DEV_TO_MEM,
+					 DMA_PREP_INTERRUPT);
+	if (!desc)
+		return -EBUSY;
+
+	desc->callback = stm32_dfsdm_audio_dma_buffer_done;
+	desc->callback_param = indio_dev;
+
+	cookie = dmaengine_submit(desc);
+	ret = dma_submit_error(cookie);
+	if (ret) {
+		dmaengine_terminate_all(adc->dma_chan);
+		return ret;
+	}
+
+	/* Issue pending DMA requests */
+	dma_async_issue_pending(adc->dma_chan);
+
+	return 0;
+}
+
+static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	int ret;
+
+	/* Reset adc buffer index */
+	adc->bufi = 0;
+
+	ret = stm32_dfsdm_start_dfsdm(adc->dfsdm);
+	if (ret < 0)
+		return ret;
+
+	ret = stm32_dfsdm_start_conv(adc, true);
+	if (ret) {
+		dev_err(&indio_dev->dev, "Can't start conversion\n");
+		goto stop_dfsdm;
+	}
+
+	if (adc->dma_chan) {
+		ret = stm32_dfsdm_adc_dma_start(indio_dev);
+		if (ret) {
+			dev_err(&indio_dev->dev, "Can't start DMA\n");
+			goto err_stop_conv;
+		}
+	}
+
+	return 0;
+
+err_stop_conv:
+	stm32_dfsdm_stop_conv(adc);
+stop_dfsdm:
+	stm32_dfsdm_stop_dfsdm(adc->dfsdm);
+
+	return ret;
+}
+
+static int stm32_dfsdm_predisable(struct iio_dev *indio_dev)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+
+	if (adc->dma_chan)
+		dmaengine_terminate_all(adc->dma_chan);
+
+	stm32_dfsdm_stop_conv(adc);
+
+	stm32_dfsdm_stop_dfsdm(adc->dfsdm);
+
+	return 0;
+}
+
+static const struct iio_buffer_setup_ops stm32_dfsdm_buffer_setup_ops = {
+	.postenable = &stm32_dfsdm_postenable,
+	.predisable = &stm32_dfsdm_predisable,
+};
+
+/**
+ * stm32_dfsdm_get_buff_cb() - register a callback that will be called when
+ *                             DMA transfer period is achieved.
+ *
+ * @iio_dev: Handle to IIO device.
+ * @cb: Pointer to callback function:
+ *      - data: pointer to data buffer
+ *      - size: size in byte of the data buffer
+ *      - private: pointer to consumer private structure.
+ * @private: Pointer to consumer private structure.
+ */
+int stm32_dfsdm_get_buff_cb(struct iio_dev *iio_dev,
+			    int (*cb)(const void *data, size_t size,
+				      void *private),
+			    void *private)
+{
+	struct stm32_dfsdm_adc *adc;
+
+	if (!iio_dev)
+		return -EINVAL;
+	adc = iio_priv(iio_dev);
+
+	adc->cb = cb;
+	adc->cb_priv = private;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(stm32_dfsdm_get_buff_cb);
+
+/**
+ * stm32_dfsdm_release_buff_cb - unregister buffer callback
+ *
+ * @iio_dev: Handle to IIO device.
+ */
+int stm32_dfsdm_release_buff_cb(struct iio_dev *iio_dev)
+{
+	struct stm32_dfsdm_adc *adc;
+
+	if (!iio_dev)
+		return -EINVAL;
+	adc = iio_priv(iio_dev);
+
+	adc->cb = NULL;
+	adc->cb_priv = NULL;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(stm32_dfsdm_release_buff_cb);
+
+static int stm32_dfsdm_single_conv(struct iio_dev *indio_dev,
+				   const struct iio_chan_spec *chan, int *res)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	long timeout;
+	int ret;
+
+	reinit_completion(&adc->completion);
+
+	adc->buffer = res;
+
+	ret = stm32_dfsdm_start_dfsdm(adc->dfsdm);
+	if (ret < 0)
+		return ret;
+
+	ret = regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id),
+				 DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(1));
+	if (ret < 0)
+		goto stop_dfsdm;
+
+	ret = stm32_dfsdm_start_conv(adc, false);
+	if (ret < 0) {
+		regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id),
+				   DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0));
+		goto stop_dfsdm;
+	}
+
+	timeout = wait_for_completion_interruptible_timeout(&adc->completion,
+							    DFSDM_TIMEOUT);
+
+	/* Mask IRQ for regular conversion achievement*/
+	regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id),
+			   DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0));
+
+	if (timeout == 0)
+		ret = -ETIMEDOUT;
+	else if (timeout < 0)
+		ret = timeout;
+	else
+		ret = IIO_VAL_INT;
+
+	stm32_dfsdm_stop_conv(adc);
+
+stop_dfsdm:
+	stm32_dfsdm_stop_dfsdm(adc->dfsdm);
+
+	return ret;
+}
+
+static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev,
+				 struct iio_chan_spec const *chan,
+				 int val, int val2, long mask)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id];
+	struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[adc->ch_id];
+	unsigned int spi_freq = adc->spi_freq;
+	int ret = -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+		ret = stm32_dfsdm_set_osrs(fl, 0, val);
+		if (!ret)
+			adc->oversamp = val;
+
+		return ret;
+
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		if (!val)
+			return -EINVAL;
+		if (ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL)
+			spi_freq = adc->dfsdm->spi_master_freq;
+
+		if (spi_freq % val)
+			dev_warn(&indio_dev->dev,
+				 "Sampling rate not accurate (%d)\n",
+				 spi_freq / (spi_freq / val));
+
+		ret = stm32_dfsdm_set_osrs(fl, 0, (spi_freq / val));
+		if (ret < 0) {
+			dev_err(&indio_dev->dev,
+				"Not able to find parameter that match!\n");
+			return ret;
+		}
+		adc->sample_freq = val;
+
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *chan, int *val,
+				int *val2, long mask)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		ret = iio_hw_consumer_enable(adc->hwc);
+		if (ret < 0) {
+			dev_err(&indio_dev->dev,
+				"%s: IIO enable failed (channel %d)\n",
+				__func__, chan->channel);
+			return ret;
+		}
+		ret = stm32_dfsdm_single_conv(indio_dev, chan, val);
+		iio_hw_consumer_disable(adc->hwc);
+		if (ret < 0) {
+			dev_err(&indio_dev->dev,
+				"%s: Conversion failed (channel %d)\n",
+				__func__, chan->channel);
+			return ret;
+		}
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+		*val = adc->oversamp;
+
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val = adc->sample_freq;
+
+		return IIO_VAL_INT;
+	}
+
+	return -EINVAL;
+}
+
+static const struct iio_info stm32_dfsdm_info_audio = {
+	.hwfifo_set_watermark = stm32_dfsdm_set_watermark,
+	.read_raw = stm32_dfsdm_read_raw,
+	.write_raw = stm32_dfsdm_write_raw,
+};
+
+static const struct iio_info stm32_dfsdm_info_adc = {
+	.read_raw = stm32_dfsdm_read_raw,
+	.write_raw = stm32_dfsdm_write_raw,
+};
+
+static irqreturn_t stm32_dfsdm_irq(int irq, void *arg)
+{
+	struct stm32_dfsdm_adc *adc = arg;
+	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+	struct regmap *regmap = adc->dfsdm->regmap;
+	unsigned int status, int_en;
+
+	regmap_read(regmap, DFSDM_ISR(adc->fl_id), &status);
+	regmap_read(regmap, DFSDM_CR2(adc->fl_id), &int_en);
+
+	if (status & DFSDM_ISR_REOCF_MASK) {
+		/* Read the data register clean the IRQ status */
+		regmap_read(regmap, DFSDM_RDATAR(adc->fl_id), adc->buffer);
+		complete(&adc->completion);
+	}
+
+	if (status & DFSDM_ISR_ROVRF_MASK) {
+		if (int_en & DFSDM_CR2_ROVRIE_MASK)
+			dev_warn(&indio_dev->dev, "Overrun detected\n");
+		regmap_update_bits(regmap, DFSDM_ICR(adc->fl_id),
+				   DFSDM_ICR_CLRROVRF_MASK,
+				   DFSDM_ICR_CLRROVRF_MASK);
+	}
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Define external info for SPI Frequency and audio sampling rate that can be
+ * configured by ASoC driver through consumer.h API
+ */
+static const struct iio_chan_spec_ext_info dfsdm_adc_audio_ext_info[] = {
+	/* spi_clk_freq : clock freq on SPI/manchester bus used by channel */
+	{
+		.name = "spi_clk_freq",
+		.shared = IIO_SHARED_BY_TYPE,
+		.read = dfsdm_adc_audio_get_spiclk,
+		.write = dfsdm_adc_audio_set_spiclk,
+	},
+	{},
+};
+
+static void stm32_dfsdm_dma_release(struct iio_dev *indio_dev)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+
+	if (adc->dma_chan) {
+		dma_free_coherent(adc->dma_chan->device->dev,
+				  DFSDM_DMA_BUFFER_SIZE,
+				  adc->rx_buf, adc->dma_buf);
+		dma_release_channel(adc->dma_chan);
+	}
+}
+
+static int stm32_dfsdm_dma_request(struct iio_dev *indio_dev)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	struct dma_slave_config config = {
+		.src_addr = (dma_addr_t)adc->dfsdm->phys_base +
+			DFSDM_RDATAR(adc->fl_id),
+		.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
+	};
+	int ret;
+
+	adc->dma_chan = dma_request_slave_channel(&indio_dev->dev, "rx");
+	if (!adc->dma_chan)
+		return -EINVAL;
+
+	adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev,
+					 DFSDM_DMA_BUFFER_SIZE,
+					 &adc->dma_buf, GFP_KERNEL);
+	if (!adc->rx_buf) {
+		ret = -ENOMEM;
+		goto err_release;
+	}
+
+	ret = dmaengine_slave_config(adc->dma_chan, &config);
+	if (ret)
+		goto err_free;
+
+	return 0;
+
+err_free:
+	dma_free_coherent(adc->dma_chan->device->dev, DFSDM_DMA_BUFFER_SIZE,
+			  adc->rx_buf, adc->dma_buf);
+err_release:
+	dma_release_channel(adc->dma_chan);
+
+	return ret;
+}
+
+static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev,
+					 struct iio_chan_spec *ch)
+{
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	int ret;
+
+	ret = stm32_dfsdm_channel_parse_of(adc->dfsdm, indio_dev, ch);
+	if (ret < 0)
+		return ret;
+
+	ch->type = IIO_VOLTAGE;
+	ch->indexed = 1;
+
+	/*
+	 * IIO_CHAN_INFO_RAW: used to compute regular conversion
+	 * IIO_CHAN_INFO_OVERSAMPLING_RATIO: used to set oversampling
+	 */
+	ch->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
+	ch->info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO);
+
+	if (adc->dev_data->type == DFSDM_AUDIO) {
+		ch->scan_type.sign = 's';
+		ch->ext_info = dfsdm_adc_audio_ext_info;
+	} else {
+		ch->scan_type.sign = 'u';
+	}
+	ch->scan_type.realbits = 24;
+	ch->scan_type.storagebits = 32;
+	adc->ch_id = ch->channel;
+
+	return stm32_dfsdm_chan_configure(adc->dfsdm,
+					  &adc->dfsdm->ch_list[ch->channel]);
+}
+
+static int stm32_dfsdm_audio_init(struct iio_dev *indio_dev)
+{
+	struct iio_chan_spec *ch;
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	struct stm32_dfsdm_channel *d_ch;
+	int ret;
+
+	indio_dev->modes |= INDIO_BUFFER_SOFTWARE;
+	indio_dev->setup_ops = &stm32_dfsdm_buffer_setup_ops;
+
+	ch = devm_kzalloc(&indio_dev->dev, sizeof(*ch), GFP_KERNEL);
+	if (!ch)
+		return -ENOMEM;
+
+	ch->scan_index = 0;
+
+	ret = stm32_dfsdm_adc_chan_init_one(indio_dev, ch);
+	if (ret < 0) {
+		dev_err(&indio_dev->dev, "Channels init failed\n");
+		return ret;
+	}
+	ch->info_mask_separate = BIT(IIO_CHAN_INFO_SAMP_FREQ);
+
+	d_ch = &adc->dfsdm->ch_list[adc->ch_id];
+	if (d_ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL)
+		adc->spi_freq = adc->dfsdm->spi_master_freq;
+
+	indio_dev->num_channels = 1;
+	indio_dev->channels = ch;
+
+	return stm32_dfsdm_dma_request(indio_dev);
+}
+
+static int stm32_dfsdm_adc_init(struct iio_dev *indio_dev)
+{
+	struct iio_chan_spec *ch;
+	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+	int num_ch;
+	int ret, chan_idx;
+
+	adc->oversamp = DFSDM_DEFAULT_OVERSAMPLING;
+	ret = stm32_dfsdm_set_osrs(&adc->dfsdm->fl_list[adc->fl_id], 0,
+				   adc->oversamp);
+	if (ret < 0)
+		return ret;
+
+	num_ch = of_property_count_u32_elems(indio_dev->dev.of_node,
+					     "st,adc-channels");
+	if (num_ch < 0 || num_ch > adc->dfsdm->num_chs) {
+		dev_err(&indio_dev->dev, "Bad st,adc-channels\n");
+		return num_ch < 0 ? num_ch : -EINVAL;
+	}
+
+	/* Bind to SD modulator IIO device */
+	adc->hwc = devm_iio_hw_consumer_alloc(&indio_dev->dev);
+	if (IS_ERR(adc->hwc))
+		return -EPROBE_DEFER;
+
+	ch = devm_kcalloc(&indio_dev->dev, num_ch, sizeof(*ch),
+			  GFP_KERNEL);
+	if (!ch)
+		return -ENOMEM;
+
+	for (chan_idx = 0; chan_idx < num_ch; chan_idx++) {
+		ch->scan_index = chan_idx;
+		ret = stm32_dfsdm_adc_chan_init_one(indio_dev, ch);
+		if (ret < 0) {
+			dev_err(&indio_dev->dev, "Channels init failed\n");
+			return ret;
+		}
+	}
+
+	indio_dev->num_channels = num_ch;
+	indio_dev->channels = ch;
+
+	init_completion(&adc->completion);
+
+	return 0;
+}
+
+static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_adc_data = {
+	.type = DFSDM_IIO,
+	.init = stm32_dfsdm_adc_init,
+};
+
+static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_audio_data = {
+	.type = DFSDM_AUDIO,
+	.init = stm32_dfsdm_audio_init,
+};
+
+static const struct of_device_id stm32_dfsdm_adc_match[] = {
+	{
+		.compatible = "st,stm32-dfsdm-adc",
+		.data = &stm32h7_dfsdm_adc_data,
+	},
+	{
+		.compatible = "st,stm32-dfsdm-dmic",
+		.data = &stm32h7_dfsdm_audio_data,
+	},
+	{}
+};
+
+static int stm32_dfsdm_adc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct stm32_dfsdm_adc *adc;
+	struct device_node *np = dev->of_node;
+	const struct stm32_dfsdm_dev_data *dev_data;
+	struct iio_dev *iio;
+	char *name;
+	int ret, irq, val;
+
+
+	dev_data = of_device_get_match_data(dev);
+	iio = devm_iio_device_alloc(dev, sizeof(*adc));
+	if (!iio) {
+		dev_err(dev, "%s: Failed to allocate IIO\n", __func__);
+		return -ENOMEM;
+	}
+
+	adc = iio_priv(iio);
+	adc->dfsdm = dev_get_drvdata(dev->parent);
+
+	iio->dev.parent = dev;
+	iio->dev.of_node = np;
+	iio->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
+
+	platform_set_drvdata(pdev, adc);
+
+	ret = of_property_read_u32(dev->of_node, "reg", &adc->fl_id);
+	if (ret != 0) {
+		dev_err(dev, "Missing reg property\n");
+		return -EINVAL;
+	}
+
+	name = devm_kzalloc(dev, sizeof("dfsdm-adc0"), GFP_KERNEL);
+	if (!name)
+		return -ENOMEM;
+	if (dev_data->type == DFSDM_AUDIO) {
+		iio->info = &stm32_dfsdm_info_audio;
+		snprintf(name, sizeof("dfsdm-pdm0"), "dfsdm-pdm%d", adc->fl_id);
+	} else {
+		iio->info = &stm32_dfsdm_info_adc;
+		snprintf(name, sizeof("dfsdm-adc0"), "dfsdm-adc%d", adc->fl_id);
+	}
+	iio->name = name;
+
+	/*
+	 * In a first step IRQs generated for channels are not treated.
+	 * So IRQ associated to filter instance 0 is dedicated to the Filter 0.
+	 */
+	irq = platform_get_irq(pdev, 0);
+	ret = devm_request_irq(dev, irq, stm32_dfsdm_irq,
+			       0, pdev->name, adc);
+	if (ret < 0) {
+		dev_err(dev, "Failed to request IRQ\n");
+		return ret;
+	}
+
+	ret = of_property_read_u32(dev->of_node, "st,filter-order", &val);
+	if (ret < 0) {
+		dev_err(dev, "Failed to set filter order\n");
+		return ret;
+	}
+
+	adc->dfsdm->fl_list[adc->fl_id].ford = val;
+
+	ret = of_property_read_u32(dev->of_node, "st,filter0-sync", &val);
+	if (!ret)
+		adc->dfsdm->fl_list[adc->fl_id].sync_mode = val;
+
+	adc->dev_data = dev_data;
+	ret = dev_data->init(iio);
+	if (ret < 0)
+		return ret;
+
+	ret = iio_device_register(iio);
+	if (ret < 0)
+		goto err_cleanup;
+
+	dev_err(dev, "of_platform_populate\n");
+	if (dev_data->type == DFSDM_AUDIO) {
+		ret = of_platform_populate(np, NULL, NULL, dev);
+		if (ret < 0) {
+			dev_err(dev, "Failed to find an audio DAI\n");
+			goto err_unregister;
+		}
+	}
+
+	return 0;
+
+err_unregister:
+	iio_device_unregister(iio);
+err_cleanup:
+	stm32_dfsdm_dma_release(iio);
+
+	return ret;
+}
+
+static int stm32_dfsdm_adc_remove(struct platform_device *pdev)
+{
+	struct stm32_dfsdm_adc *adc = platform_get_drvdata(pdev);
+	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+
+	if (adc->dev_data->type == DFSDM_AUDIO)
+		of_platform_depopulate(&pdev->dev);
+	iio_device_unregister(indio_dev);
+	stm32_dfsdm_dma_release(indio_dev);
+
+	return 0;
+}
+
+static struct platform_driver stm32_dfsdm_adc_driver = {
+	.driver = {
+		.name = "stm32-dfsdm-adc",
+		.of_match_table = stm32_dfsdm_adc_match,
+	},
+	.probe = stm32_dfsdm_adc_probe,
+	.remove = stm32_dfsdm_adc_remove,
+};
+module_platform_driver(stm32_dfsdm_adc_driver);
+
+MODULE_DESCRIPTION("STM32 sigma delta ADC");
+MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/adc/stm32-dfsdm-core.c b/drivers/iio/adc/stm32-dfsdm-core.c
new file mode 100644
index 000000000000..6290332cfd3f
--- /dev/null
+++ b/drivers/iio/adc/stm32-dfsdm-core.c
@@ -0,0 +1,302 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This file is part the core part STM32 DFSDM driver
+ *
+ * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
+ * Author(s): Arnaud Pouliquen <arnaud.pouliquen@st.com> for STMicroelectronics.
+ */
+
+#include <linux/clk.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include "stm32-dfsdm.h"
+
+struct stm32_dfsdm_dev_data {
+	unsigned int num_filters;
+	unsigned int num_channels;
+	const struct regmap_config *regmap_cfg;
+};
+
+#define STM32H7_DFSDM_NUM_FILTERS	4
+#define STM32H7_DFSDM_NUM_CHANNELS	8
+
+static bool stm32_dfsdm_volatile_reg(struct device *dev, unsigned int reg)
+{
+	if (reg < DFSDM_FILTER_BASE_ADR)
+		return false;
+
+	/*
+	 * Mask is done on register to avoid to list registers of all
+	 * filter instances.
+	 */
+	switch (reg & DFSDM_FILTER_REG_MASK) {
+	case DFSDM_CR1(0) & DFSDM_FILTER_REG_MASK:
+	case DFSDM_ISR(0) & DFSDM_FILTER_REG_MASK:
+	case DFSDM_JDATAR(0) & DFSDM_FILTER_REG_MASK:
+	case DFSDM_RDATAR(0) & DFSDM_FILTER_REG_MASK:
+		return true;
+	}
+
+	return false;
+}
+
+static const struct regmap_config stm32h7_dfsdm_regmap_cfg = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = sizeof(u32),
+	.max_register = 0x2B8,
+	.volatile_reg = stm32_dfsdm_volatile_reg,
+	.fast_io = true,
+};
+
+static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_data = {
+	.num_filters = STM32H7_DFSDM_NUM_FILTERS,
+	.num_channels = STM32H7_DFSDM_NUM_CHANNELS,
+	.regmap_cfg = &stm32h7_dfsdm_regmap_cfg,
+};
+
+struct dfsdm_priv {
+	struct platform_device *pdev; /* platform device */
+
+	struct stm32_dfsdm dfsdm; /* common data exported for all instances */
+
+	unsigned int spi_clk_out_div; /* SPI clkout divider value */
+	atomic_t n_active_ch;	/* number of current active channels */
+
+	struct clk *clk; /* DFSDM clock */
+	struct clk *aclk; /* audio clock */
+};
+
+/**
+ * stm32_dfsdm_start_dfsdm - start global dfsdm interface.
+ *
+ * Enable interface if n_active_ch is not null.
+ * @dfsdm: Handle used to retrieve dfsdm context.
+ */
+int stm32_dfsdm_start_dfsdm(struct stm32_dfsdm *dfsdm)
+{
+	struct dfsdm_priv *priv = container_of(dfsdm, struct dfsdm_priv, dfsdm);
+	struct device *dev = &priv->pdev->dev;
+	unsigned int clk_div = priv->spi_clk_out_div;
+	int ret;
+
+	if (atomic_inc_return(&priv->n_active_ch) == 1) {
+		ret = clk_prepare_enable(priv->clk);
+		if (ret < 0) {
+			dev_err(dev, "Failed to start clock\n");
+			goto error_ret;
+		}
+		if (priv->aclk) {
+			ret = clk_prepare_enable(priv->aclk);
+			if (ret < 0) {
+				dev_err(dev, "Failed to start audio clock\n");
+				goto disable_clk;
+			}
+		}
+
+		/* Output the SPI CLKOUT (if clk_div == 0 clock if OFF) */
+		ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
+					 DFSDM_CHCFGR1_CKOUTDIV_MASK,
+					 DFSDM_CHCFGR1_CKOUTDIV(clk_div));
+		if (ret < 0)
+			goto disable_aclk;
+
+		/* Global enable of DFSDM interface */
+		ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
+					 DFSDM_CHCFGR1_DFSDMEN_MASK,
+					 DFSDM_CHCFGR1_DFSDMEN(1));
+		if (ret < 0)
+			goto disable_aclk;
+	}
+
+	dev_dbg(dev, "%s: n_active_ch %d\n", __func__,
+		atomic_read(&priv->n_active_ch));
+
+	return 0;
+
+disable_aclk:
+	clk_disable_unprepare(priv->aclk);
+disable_clk:
+	clk_disable_unprepare(priv->clk);
+
+error_ret:
+	atomic_dec(&priv->n_active_ch);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(stm32_dfsdm_start_dfsdm);
+
+/**
+ * stm32_dfsdm_stop_dfsdm - stop global DFSDM interface.
+ *
+ * Disable interface if n_active_ch is null
+ * @dfsdm: Handle used to retrieve dfsdm context.
+ */
+int stm32_dfsdm_stop_dfsdm(struct stm32_dfsdm *dfsdm)
+{
+	struct dfsdm_priv *priv = container_of(dfsdm, struct dfsdm_priv, dfsdm);
+	int ret;
+
+	if (atomic_dec_and_test(&priv->n_active_ch)) {
+		/* Global disable of DFSDM interface */
+		ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
+					 DFSDM_CHCFGR1_DFSDMEN_MASK,
+					 DFSDM_CHCFGR1_DFSDMEN(0));
+		if (ret < 0)
+			return ret;
+
+		/* Stop SPI CLKOUT */
+		ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
+					 DFSDM_CHCFGR1_CKOUTDIV_MASK,
+					 DFSDM_CHCFGR1_CKOUTDIV(0));
+		if (ret < 0)
+			return ret;
+
+		clk_disable_unprepare(priv->clk);
+		if (priv->aclk)
+			clk_disable_unprepare(priv->aclk);
+	}
+	dev_dbg(&priv->pdev->dev, "%s: n_active_ch %d\n", __func__,
+		atomic_read(&priv->n_active_ch));
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(stm32_dfsdm_stop_dfsdm);
+
+static int stm32_dfsdm_parse_of(struct platform_device *pdev,
+				struct dfsdm_priv *priv)
+{
+	struct device_node *node = pdev->dev.of_node;
+	struct resource *res;
+	unsigned long clk_freq;
+	unsigned int spi_freq, rem;
+	int ret;
+
+	if (!node)
+		return -EINVAL;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "Failed to get memory resource\n");
+		return -ENODEV;
+	}
+	priv->dfsdm.phys_base = res->start;
+	priv->dfsdm.base = devm_ioremap_resource(&pdev->dev, res);
+
+	/*
+	 * "dfsdm" clock is mandatory for DFSDM peripheral clocking.
+	 * "dfsdm" or "audio" clocks can be used as source clock for
+	 * the SPI clock out signal and internal processing, depending
+	 * on use case.
+	 */
+	priv->clk = devm_clk_get(&pdev->dev, "dfsdm");
+	if (IS_ERR(priv->clk)) {
+		dev_err(&pdev->dev, "No stm32_dfsdm_clk clock found\n");
+		return -EINVAL;
+	}
+
+	priv->aclk = devm_clk_get(&pdev->dev, "audio");
+	if (IS_ERR(priv->aclk))
+		priv->aclk = NULL;
+
+	if (priv->aclk)
+		clk_freq = clk_get_rate(priv->aclk);
+	else
+		clk_freq = clk_get_rate(priv->clk);
+
+	/* SPI clock out frequency */
+	ret = of_property_read_u32(pdev->dev.of_node, "spi-max-frequency",
+				   &spi_freq);
+	if (ret < 0) {
+		/* No SPI master mode */
+		return 0;
+	}
+
+	priv->spi_clk_out_div = div_u64_rem(clk_freq, spi_freq, &rem) - 1;
+	priv->dfsdm.spi_master_freq = spi_freq;
+
+	if (rem) {
+		dev_warn(&pdev->dev, "SPI clock not accurate\n");
+		dev_warn(&pdev->dev, "%ld = %d * %d + %d\n",
+			 clk_freq, spi_freq, priv->spi_clk_out_div + 1, rem);
+	}
+
+	return 0;
+};
+
+static const struct of_device_id stm32_dfsdm_of_match[] = {
+	{
+		.compatible = "st,stm32h7-dfsdm",
+		.data = &stm32h7_dfsdm_data,
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, stm32_dfsdm_of_match);
+
+static int stm32_dfsdm_probe(struct platform_device *pdev)
+{
+	struct dfsdm_priv *priv;
+	const struct stm32_dfsdm_dev_data *dev_data;
+	struct stm32_dfsdm *dfsdm;
+	int ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->pdev = pdev;
+
+	dev_data = of_device_get_match_data(&pdev->dev);
+
+	dfsdm = &priv->dfsdm;
+	dfsdm->fl_list = devm_kcalloc(&pdev->dev, dev_data->num_filters,
+				      sizeof(*dfsdm->fl_list), GFP_KERNEL);
+	if (!dfsdm->fl_list)
+		return -ENOMEM;
+
+	dfsdm->num_fls = dev_data->num_filters;
+	dfsdm->ch_list = devm_kcalloc(&pdev->dev, dev_data->num_channels,
+				      sizeof(*dfsdm->ch_list),
+				      GFP_KERNEL);
+	if (!dfsdm->ch_list)
+		return -ENOMEM;
+	dfsdm->num_chs = dev_data->num_channels;
+
+	ret = stm32_dfsdm_parse_of(pdev, priv);
+	if (ret < 0)
+		return ret;
+
+	dfsdm->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "dfsdm",
+						  dfsdm->base,
+						  &stm32h7_dfsdm_regmap_cfg);
+	if (IS_ERR(dfsdm->regmap)) {
+		ret = PTR_ERR(dfsdm->regmap);
+		dev_err(&pdev->dev, "%s: Failed to allocate regmap: %d\n",
+			__func__, ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, dfsdm);
+
+	return devm_of_platform_populate(&pdev->dev);
+}
+
+static struct platform_driver stm32_dfsdm_driver = {
+	.probe = stm32_dfsdm_probe,
+	.driver = {
+		.name = "stm32-dfsdm",
+		.of_match_table = stm32_dfsdm_of_match,
+	},
+};
+
+module_platform_driver(stm32_dfsdm_driver);
+
+MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics STM32 dfsdm driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/adc/stm32-dfsdm.h b/drivers/iio/adc/stm32-dfsdm.h
new file mode 100644
index 000000000000..8708394b0725
--- /dev/null
+++ b/drivers/iio/adc/stm32-dfsdm.h
@@ -0,0 +1,310 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This file is part of STM32 DFSDM driver
+ *
+ * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
+ * Author(s): Arnaud Pouliquen <arnaud.pouliquen@st.com>.
+ */
+
+#ifndef MDF_STM32_DFSDM__H
+#define MDF_STM32_DFSDM__H
+
+#include <linux/bitfield.h>
+
+/*
+ * STM32 DFSDM - global register map
+ * ________________________________________________________
+ * | Offset |                 Registers block             |
+ * --------------------------------------------------------
+ * | 0x000  |      CHANNEL 0 + COMMON CHANNEL FIELDS      |
+ * --------------------------------------------------------
+ * | 0x020  |                CHANNEL 1                    |
+ * --------------------------------------------------------
+ * | ...    |                .....                        |
+ * --------------------------------------------------------
+ * | 0x0E0  |                CHANNEL 7                    |
+ * --------------------------------------------------------
+ * | 0x100  |      FILTER  0 + COMMON  FILTER FIELDs      |
+ * --------------------------------------------------------
+ * | 0x200  |                FILTER  1                    |
+ * --------------------------------------------------------
+ * | 0x300  |                FILTER  2                    |
+ * --------------------------------------------------------
+ * | 0x400  |                FILTER  3                    |
+ * --------------------------------------------------------
+ */
+
+/*
+ * Channels register definitions
+ */
+#define DFSDM_CHCFGR1(y)  ((y) * 0x20 + 0x00)
+#define DFSDM_CHCFGR2(y)  ((y) * 0x20 + 0x04)
+#define DFSDM_AWSCDR(y)   ((y) * 0x20 + 0x08)
+#define DFSDM_CHWDATR(y)  ((y) * 0x20 + 0x0C)
+#define DFSDM_CHDATINR(y) ((y) * 0x20 + 0x10)
+
+/* CHCFGR1: Channel configuration register 1 */
+#define DFSDM_CHCFGR1_SITP_MASK     GENMASK(1, 0)
+#define DFSDM_CHCFGR1_SITP(v)       FIELD_PREP(DFSDM_CHCFGR1_SITP_MASK, v)
+#define DFSDM_CHCFGR1_SPICKSEL_MASK GENMASK(3, 2)
+#define DFSDM_CHCFGR1_SPICKSEL(v)   FIELD_PREP(DFSDM_CHCFGR1_SPICKSEL_MASK, v)
+#define DFSDM_CHCFGR1_SCDEN_MASK    BIT(5)
+#define DFSDM_CHCFGR1_SCDEN(v)      FIELD_PREP(DFSDM_CHCFGR1_SCDEN_MASK, v)
+#define DFSDM_CHCFGR1_CKABEN_MASK   BIT(6)
+#define DFSDM_CHCFGR1_CKABEN(v)     FIELD_PREP(DFSDM_CHCFGR1_CKABEN_MASK, v)
+#define DFSDM_CHCFGR1_CHEN_MASK     BIT(7)
+#define DFSDM_CHCFGR1_CHEN(v)       FIELD_PREP(DFSDM_CHCFGR1_CHEN_MASK, v)
+#define DFSDM_CHCFGR1_CHINSEL_MASK  BIT(8)
+#define DFSDM_CHCFGR1_CHINSEL(v)    FIELD_PREP(DFSDM_CHCFGR1_CHINSEL_MASK, v)
+#define DFSDM_CHCFGR1_DATMPX_MASK   GENMASK(13, 12)
+#define DFSDM_CHCFGR1_DATMPX(v)     FIELD_PREP(DFSDM_CHCFGR1_DATMPX_MASK, v)
+#define DFSDM_CHCFGR1_DATPACK_MASK  GENMASK(15, 14)
+#define DFSDM_CHCFGR1_DATPACK(v)    FIELD_PREP(DFSDM_CHCFGR1_DATPACK_MASK, v)
+#define DFSDM_CHCFGR1_CKOUTDIV_MASK GENMASK(23, 16)
+#define DFSDM_CHCFGR1_CKOUTDIV(v)   FIELD_PREP(DFSDM_CHCFGR1_CKOUTDIV_MASK, v)
+#define DFSDM_CHCFGR1_CKOUTSRC_MASK BIT(30)
+#define DFSDM_CHCFGR1_CKOUTSRC(v)   FIELD_PREP(DFSDM_CHCFGR1_CKOUTSRC_MASK, v)
+#define DFSDM_CHCFGR1_DFSDMEN_MASK  BIT(31)
+#define DFSDM_CHCFGR1_DFSDMEN(v)    FIELD_PREP(DFSDM_CHCFGR1_DFSDMEN_MASK, v)
+
+/* CHCFGR2: Channel configuration register 2 */
+#define DFSDM_CHCFGR2_DTRBS_MASK    GENMASK(7, 3)
+#define DFSDM_CHCFGR2_DTRBS(v)      FIELD_PREP(DFSDM_CHCFGR2_DTRBS_MASK, v)
+#define DFSDM_CHCFGR2_OFFSET_MASK   GENMASK(31, 8)
+#define DFSDM_CHCFGR2_OFFSET(v)     FIELD_PREP(DFSDM_CHCFGR2_OFFSET_MASK, v)
+
+/* AWSCDR: Channel analog watchdog and short circuit detector */
+#define DFSDM_AWSCDR_SCDT_MASK    GENMASK(7, 0)
+#define DFSDM_AWSCDR_SCDT(v)      FIELD_PREP(DFSDM_AWSCDR_SCDT_MASK, v)
+#define DFSDM_AWSCDR_BKSCD_MASK   GENMASK(15, 12)
+#define DFSDM_AWSCDR_BKSCD(v)	  FIELD_PREP(DFSDM_AWSCDR_BKSCD_MASK, v)
+#define DFSDM_AWSCDR_AWFOSR_MASK  GENMASK(20, 16)
+#define DFSDM_AWSCDR_AWFOSR(v)    FIELD_PREP(DFSDM_AWSCDR_AWFOSR_MASK, v)
+#define DFSDM_AWSCDR_AWFORD_MASK  GENMASK(23, 22)
+#define DFSDM_AWSCDR_AWFORD(v)    FIELD_PREP(DFSDM_AWSCDR_AWFORD_MASK, v)
+
+/*
+ * Filters register definitions
+ */
+#define DFSDM_FILTER_BASE_ADR		0x100
+#define DFSDM_FILTER_REG_MASK		0x7F
+#define DFSDM_FILTER_X_BASE_ADR(x)	((x) * 0x80 + DFSDM_FILTER_BASE_ADR)
+
+#define DFSDM_CR1(x)     (DFSDM_FILTER_X_BASE_ADR(x)  + 0x00)
+#define DFSDM_CR2(x)     (DFSDM_FILTER_X_BASE_ADR(x)  + 0x04)
+#define DFSDM_ISR(x)     (DFSDM_FILTER_X_BASE_ADR(x)  + 0x08)
+#define DFSDM_ICR(x)     (DFSDM_FILTER_X_BASE_ADR(x)  + 0x0C)
+#define DFSDM_JCHGR(x)   (DFSDM_FILTER_X_BASE_ADR(x)  + 0x10)
+#define DFSDM_FCR(x)     (DFSDM_FILTER_X_BASE_ADR(x)  + 0x14)
+#define DFSDM_JDATAR(x)  (DFSDM_FILTER_X_BASE_ADR(x)  + 0x18)
+#define DFSDM_RDATAR(x)  (DFSDM_FILTER_X_BASE_ADR(x)  + 0x1C)
+#define DFSDM_AWHTR(x)   (DFSDM_FILTER_X_BASE_ADR(x)  + 0x20)
+#define DFSDM_AWLTR(x)   (DFSDM_FILTER_X_BASE_ADR(x)  + 0x24)
+#define DFSDM_AWSR(x)    (DFSDM_FILTER_X_BASE_ADR(x)  + 0x28)
+#define DFSDM_AWCFR(x)   (DFSDM_FILTER_X_BASE_ADR(x)  + 0x2C)
+#define DFSDM_EXMAX(x)   (DFSDM_FILTER_X_BASE_ADR(x)  + 0x30)
+#define DFSDM_EXMIN(x)   (DFSDM_FILTER_X_BASE_ADR(x)  + 0x34)
+#define DFSDM_CNVTIMR(x) (DFSDM_FILTER_X_BASE_ADR(x)  + 0x38)
+
+/* CR1 Control register 1 */
+#define DFSDM_CR1_DFEN_MASK	BIT(0)
+#define DFSDM_CR1_DFEN(v)	FIELD_PREP(DFSDM_CR1_DFEN_MASK, v)
+#define DFSDM_CR1_JSWSTART_MASK	BIT(1)
+#define DFSDM_CR1_JSWSTART(v)	FIELD_PREP(DFSDM_CR1_JSWSTART_MASK, v)
+#define DFSDM_CR1_JSYNC_MASK	BIT(3)
+#define DFSDM_CR1_JSYNC(v)	FIELD_PREP(DFSDM_CR1_JSYNC_MASK, v)
+#define DFSDM_CR1_JSCAN_MASK	BIT(4)
+#define DFSDM_CR1_JSCAN(v)	FIELD_PREP(DFSDM_CR1_JSCAN_MASK, v)
+#define DFSDM_CR1_JDMAEN_MASK	BIT(5)
+#define DFSDM_CR1_JDMAEN(v)	FIELD_PREP(DFSDM_CR1_JDMAEN_MASK, v)
+#define DFSDM_CR1_JEXTSEL_MASK	GENMASK(12, 8)
+#define DFSDM_CR1_JEXTSEL(v)	FIELD_PREP(DFSDM_CR1_JEXTSEL_MASK, v)
+#define DFSDM_CR1_JEXTEN_MASK	GENMASK(14, 13)
+#define DFSDM_CR1_JEXTEN(v)	FIELD_PREP(DFSDM_CR1_JEXTEN_MASK, v)
+#define DFSDM_CR1_RSWSTART_MASK	BIT(17)
+#define DFSDM_CR1_RSWSTART(v)	FIELD_PREP(DFSDM_CR1_RSWSTART_MASK, v)
+#define DFSDM_CR1_RCONT_MASK	BIT(18)
+#define DFSDM_CR1_RCONT(v)	FIELD_PREP(DFSDM_CR1_RCONT_MASK, v)
+#define DFSDM_CR1_RSYNC_MASK	BIT(19)
+#define DFSDM_CR1_RSYNC(v)	FIELD_PREP(DFSDM_CR1_RSYNC_MASK, v)
+#define DFSDM_CR1_RDMAEN_MASK	BIT(21)
+#define DFSDM_CR1_RDMAEN(v)	FIELD_PREP(DFSDM_CR1_RDMAEN_MASK, v)
+#define DFSDM_CR1_RCH_MASK	GENMASK(26, 24)
+#define DFSDM_CR1_RCH(v)	FIELD_PREP(DFSDM_CR1_RCH_MASK, v)
+#define DFSDM_CR1_FAST_MASK	BIT(29)
+#define DFSDM_CR1_FAST(v)	FIELD_PREP(DFSDM_CR1_FAST_MASK, v)
+#define DFSDM_CR1_AWFSEL_MASK	BIT(30)
+#define DFSDM_CR1_AWFSEL(v)	FIELD_PREP(DFSDM_CR1_AWFSEL_MASK, v)
+
+/* CR2: Control register 2 */
+#define DFSDM_CR2_IE_MASK	GENMASK(6, 0)
+#define DFSDM_CR2_IE(v)		FIELD_PREP(DFSDM_CR2_IE_MASK, v)
+#define DFSDM_CR2_JEOCIE_MASK	BIT(0)
+#define DFSDM_CR2_JEOCIE(v)	FIELD_PREP(DFSDM_CR2_JEOCIE_MASK, v)
+#define DFSDM_CR2_REOCIE_MASK	BIT(1)
+#define DFSDM_CR2_REOCIE(v)	FIELD_PREP(DFSDM_CR2_REOCIE_MASK, v)
+#define DFSDM_CR2_JOVRIE_MASK	BIT(2)
+#define DFSDM_CR2_JOVRIE(v)	FIELD_PREP(DFSDM_CR2_JOVRIE_MASK, v)
+#define DFSDM_CR2_ROVRIE_MASK	BIT(3)
+#define DFSDM_CR2_ROVRIE(v)	FIELD_PREP(DFSDM_CR2_ROVRIE_MASK, v)
+#define DFSDM_CR2_AWDIE_MASK	BIT(4)
+#define DFSDM_CR2_AWDIE(v)	FIELD_PREP(DFSDM_CR2_AWDIE_MASK, v)
+#define DFSDM_CR2_SCDIE_MASK	BIT(5)
+#define DFSDM_CR2_SCDIE(v)	FIELD_PREP(DFSDM_CR2_SCDIE_MASK, v)
+#define DFSDM_CR2_CKABIE_MASK	BIT(6)
+#define DFSDM_CR2_CKABIE(v)	FIELD_PREP(DFSDM_CR2_CKABIE_MASK, v)
+#define DFSDM_CR2_EXCH_MASK	GENMASK(15, 8)
+#define DFSDM_CR2_EXCH(v)	FIELD_PREP(DFSDM_CR2_EXCH_MASK, v)
+#define DFSDM_CR2_AWDCH_MASK	GENMASK(23, 16)
+#define DFSDM_CR2_AWDCH(v)	FIELD_PREP(DFSDM_CR2_AWDCH_MASK, v)
+
+/* ISR: Interrupt status register */
+#define DFSDM_ISR_JEOCF_MASK	BIT(0)
+#define DFSDM_ISR_JEOCF(v)	FIELD_PREP(DFSDM_ISR_JEOCF_MASK, v)
+#define DFSDM_ISR_REOCF_MASK	BIT(1)
+#define DFSDM_ISR_REOCF(v)	FIELD_PREP(DFSDM_ISR_REOCF_MASK, v)
+#define DFSDM_ISR_JOVRF_MASK	BIT(2)
+#define DFSDM_ISR_JOVRF(v)	FIELD_PREP(DFSDM_ISR_JOVRF_MASK, v)
+#define DFSDM_ISR_ROVRF_MASK	BIT(3)
+#define DFSDM_ISR_ROVRF(v)	FIELD_PREP(DFSDM_ISR_ROVRF_MASK, v)
+#define DFSDM_ISR_AWDF_MASK	BIT(4)
+#define DFSDM_ISR_AWDF(v)	FIELD_PREP(DFSDM_ISR_AWDF_MASK, v)
+#define DFSDM_ISR_JCIP_MASK	BIT(13)
+#define DFSDM_ISR_JCIP(v)	FIELD_PREP(DFSDM_ISR_JCIP_MASK, v)
+#define DFSDM_ISR_RCIP_MASK	BIT(14)
+#define DFSDM_ISR_RCIP(v)	FIELD_PREP(DFSDM_ISR_RCIP, v)
+#define DFSDM_ISR_CKABF_MASK	GENMASK(23, 16)
+#define DFSDM_ISR_CKABF(v)	FIELD_PREP(DFSDM_ISR_CKABF_MASK, v)
+#define DFSDM_ISR_SCDF_MASK	GENMASK(31, 24)
+#define DFSDM_ISR_SCDF(v)	FIELD_PREP(DFSDM_ISR_SCDF_MASK, v)
+
+/* ICR: Interrupt flag clear register */
+#define DFSDM_ICR_CLRJOVRF_MASK	      BIT(2)
+#define DFSDM_ICR_CLRJOVRF(v)	      FIELD_PREP(DFSDM_ICR_CLRJOVRF_MASK, v)
+#define DFSDM_ICR_CLRROVRF_MASK	      BIT(3)
+#define DFSDM_ICR_CLRROVRF(v)	      FIELD_PREP(DFSDM_ICR_CLRROVRF_MASK, v)
+#define DFSDM_ICR_CLRCKABF_MASK	      GENMASK(23, 16)
+#define DFSDM_ICR_CLRCKABF(v)	      FIELD_PREP(DFSDM_ICR_CLRCKABF_MASK, v)
+#define DFSDM_ICR_CLRCKABF_CH_MASK(y) BIT(16 + (y))
+#define DFSDM_ICR_CLRCKABF_CH(v, y)   \
+			   (((v) << (16 + (y))) & DFSDM_ICR_CLRCKABF_CH_MASK(y))
+#define DFSDM_ICR_CLRSCDF_MASK	      GENMASK(31, 24)
+#define DFSDM_ICR_CLRSCDF(v)	      FIELD_PREP(DFSDM_ICR_CLRSCDF_MASK, v)
+#define DFSDM_ICR_CLRSCDF_CH_MASK(y)  BIT(24 + (y))
+#define DFSDM_ICR_CLRSCDF_CH(v, y)    \
+			       (((v) << (24 + (y))) & DFSDM_ICR_CLRSCDF_MASK(y))
+
+/* FCR: Filter control register */
+#define DFSDM_FCR_IOSR_MASK	GENMASK(7, 0)
+#define DFSDM_FCR_IOSR(v)	FIELD_PREP(DFSDM_FCR_IOSR_MASK, v)
+#define DFSDM_FCR_FOSR_MASK	GENMASK(25, 16)
+#define DFSDM_FCR_FOSR(v)	FIELD_PREP(DFSDM_FCR_FOSR_MASK, v)
+#define DFSDM_FCR_FORD_MASK	GENMASK(31, 29)
+#define DFSDM_FCR_FORD(v)	FIELD_PREP(DFSDM_FCR_FORD_MASK, v)
+
+/* RDATAR: Filter data register for regular channel */
+#define DFSDM_DATAR_CH_MASK	GENMASK(2, 0)
+#define DFSDM_DATAR_DATA_OFFSET 8
+#define DFSDM_DATAR_DATA_MASK	GENMASK(31, DFSDM_DATAR_DATA_OFFSET)
+
+/* AWLTR: Filter analog watchdog low threshold register */
+#define DFSDM_AWLTR_BKAWL_MASK	GENMASK(3, 0)
+#define DFSDM_AWLTR_BKAWL(v)	FIELD_PREP(DFSDM_AWLTR_BKAWL_MASK, v)
+#define DFSDM_AWLTR_AWLT_MASK	GENMASK(31, 8)
+#define DFSDM_AWLTR_AWLT(v)	FIELD_PREP(DFSDM_AWLTR_AWLT_MASK, v)
+
+/* AWHTR: Filter analog watchdog low threshold register */
+#define DFSDM_AWHTR_BKAWH_MASK	GENMASK(3, 0)
+#define DFSDM_AWHTR_BKAWH(v)	FIELD_PREP(DFSDM_AWHTR_BKAWH_MASK, v)
+#define DFSDM_AWHTR_AWHT_MASK	GENMASK(31, 8)
+#define DFSDM_AWHTR_AWHT(v)	FIELD_PREP(DFSDM_AWHTR_AWHT_MASK, v)
+
+/* AWSR: Filter watchdog status register */
+#define DFSDM_AWSR_AWLTF_MASK	GENMASK(7, 0)
+#define DFSDM_AWSR_AWLTF(v)	FIELD_PREP(DFSDM_AWSR_AWLTF_MASK, v)
+#define DFSDM_AWSR_AWHTF_MASK	GENMASK(15, 8)
+#define DFSDM_AWSR_AWHTF(v)	FIELD_PREP(DFSDM_AWSR_AWHTF_MASK, v)
+
+/* AWCFR: Filter watchdog status register */
+#define DFSDM_AWCFR_AWLTF_MASK	GENMASK(7, 0)
+#define DFSDM_AWCFR_AWLTF(v)	FIELD_PREP(DFSDM_AWCFR_AWLTF_MASK, v)
+#define DFSDM_AWCFR_AWHTF_MASK	GENMASK(15, 8)
+#define DFSDM_AWCFR_AWHTF(v)	FIELD_PREP(DFSDM_AWCFR_AWHTF_MASK, v)
+
+/* DFSDM filter order  */
+enum stm32_dfsdm_sinc_order {
+	DFSDM_FASTSINC_ORDER, /* FastSinc filter type */
+	DFSDM_SINC1_ORDER,    /* Sinc 1 filter type */
+	DFSDM_SINC2_ORDER,    /* Sinc 2 filter type */
+	DFSDM_SINC3_ORDER,    /* Sinc 3 filter type */
+	DFSDM_SINC4_ORDER,    /* Sinc 4 filter type (N.A. for watchdog) */
+	DFSDM_SINC5_ORDER,    /* Sinc 5 filter type (N.A. for watchdog) */
+	DFSDM_NB_SINC_ORDER,
+};
+
+/**
+ * struct stm32_dfsdm_filter - structure relative to stm32 FDSDM filter
+ * @iosr: integrator oversampling
+ * @fosr: filter oversampling
+ * @ford: filter order
+ * @res: output sample resolution
+ * @sync_mode: filter synchronized with filter 0
+ * @fast: filter fast mode
+ */
+struct stm32_dfsdm_filter {
+	unsigned int iosr;
+	unsigned int fosr;
+	enum stm32_dfsdm_sinc_order ford;
+	u64 res;
+	unsigned int sync_mode;
+	unsigned int fast;
+};
+
+/**
+ * struct stm32_dfsdm_channel - structure relative to stm32 FDSDM channel
+ * @id: id of the channel
+ * @type: interface type linked to stm32_dfsdm_chan_type
+ * @src: interface type linked to stm32_dfsdm_chan_src
+ * @alt_si: alternative serial input interface
+ */
+struct stm32_dfsdm_channel {
+	unsigned int id;
+	unsigned int type;
+	unsigned int src;
+	unsigned int alt_si;
+};
+
+/**
+ * struct stm32_dfsdm - stm32 FDSDM driver common data (for all instances)
+ * @base:	control registers base cpu addr
+ * @phys_base:	DFSDM IP register physical address
+ * @regmap:	regmap for register read/write
+ * @fl_list:	filter resources list
+ * @num_fls:	number of filter resources available
+ * @ch_list:	channel resources list
+ * @num_chs:	number of channel resources available
+ * @spi_master_freq: SPI clock out frequency
+ */
+struct stm32_dfsdm {
+	void __iomem	*base;
+	phys_addr_t	phys_base;
+	struct regmap *regmap;
+	struct stm32_dfsdm_filter *fl_list;
+	unsigned int num_fls;
+	struct stm32_dfsdm_channel *ch_list;
+	unsigned int num_chs;
+	unsigned int spi_master_freq;
+};
+
+/* DFSDM channel serial spi clock source */
+enum stm32_dfsdm_spi_clk_src {
+	DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL,
+	DFSDM_CHANNEL_SPI_CLOCK_INTERNAL,
+	DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING,
+	DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING
+};
+
+int stm32_dfsdm_start_dfsdm(struct stm32_dfsdm *dfsdm);
+int stm32_dfsdm_stop_dfsdm(struct stm32_dfsdm *dfsdm);
+
+#endif
diff --git a/drivers/iio/buffer/Kconfig b/drivers/iio/buffer/Kconfig
index 4ffd3db7817f..338774cba19b 100644
--- a/drivers/iio/buffer/Kconfig
+++ b/drivers/iio/buffer/Kconfig
@@ -29,6 +29,16 @@ config IIO_BUFFER_DMAENGINE
 
 	  Should be selected by drivers that want to use this functionality.
 
+config IIO_BUFFER_HW_CONSUMER
+	tristate "Industrial I/O HW buffering"
+	help
+	  Provides a way to bonding when an IIO device has a direct connection
+	  to another device in hardware. In this case buffers for data transfers
+	  are handled by hardware.
+
+	  Should be selected by drivers that want to use the generic Hw consumer
+	  interface.
+
 config IIO_KFIFO_BUF
 	tristate "Industrial I/O buffering based on kfifo"
 	help
diff --git a/drivers/iio/buffer/Makefile b/drivers/iio/buffer/Makefile
index 95f9f41c58b7..1403eb2f9409 100644
--- a/drivers/iio/buffer/Makefile
+++ b/drivers/iio/buffer/Makefile
@@ -7,5 +7,6 @@
 obj-$(CONFIG_IIO_BUFFER_CB) += industrialio-buffer-cb.o
 obj-$(CONFIG_IIO_BUFFER_DMA) += industrialio-buffer-dma.o
 obj-$(CONFIG_IIO_BUFFER_DMAENGINE) += industrialio-buffer-dmaengine.o
+obj-$(CONFIG_IIO_BUFFER_HW_CONSUMER) += industrialio-hw-consumer.o
 obj-$(CONFIG_IIO_TRIGGERED_BUFFER) += industrialio-triggered-buffer.o
 obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o
diff --git a/drivers/iio/buffer/industrialio-buffer-cb.c b/drivers/iio/buffer/industrialio-buffer-cb.c
index 4847534700e7..ea63c838eeae 100644
--- a/drivers/iio/buffer/industrialio-buffer-cb.c
+++ b/drivers/iio/buffer/industrialio-buffer-cb.c
@@ -104,6 +104,17 @@ error_free_cb_buff:
 }
 EXPORT_SYMBOL_GPL(iio_channel_get_all_cb);
 
+int iio_channel_cb_set_buffer_watermark(struct iio_cb_buffer *cb_buff,
+					size_t watermark)
+{
+	if (!watermark)
+		return -EINVAL;
+	cb_buff->buffer.watermark = watermark;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(iio_channel_cb_set_buffer_watermark);
+
 int iio_channel_start_all_cb(struct iio_cb_buffer *cb_buff)
 {
 	return iio_update_buffers(cb_buff->indio_dev, &cb_buff->buffer,
diff --git a/drivers/iio/buffer/industrialio-hw-consumer.c b/drivers/iio/buffer/industrialio-hw-consumer.c
new file mode 100644
index 000000000000..95165697d8ae
--- /dev/null
+++ b/drivers/iio/buffer/industrialio-hw-consumer.c
@@ -0,0 +1,247 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2017 Analog Devices Inc.
+ *  Author: Lars-Peter Clausen <lars@metafoo.de>
+ */
+
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/consumer.h>
+#include <linux/iio/hw-consumer.h>
+#include <linux/iio/buffer_impl.h>
+
+/**
+ * struct iio_hw_consumer - IIO hw consumer block
+ * @buffers: hardware buffers list head.
+ * @channels: IIO provider channels.
+ */
+struct iio_hw_consumer {
+	struct list_head buffers;
+	struct iio_channel *channels;
+};
+
+struct hw_consumer_buffer {
+	struct list_head head;
+	struct iio_dev *indio_dev;
+	struct iio_buffer buffer;
+	long scan_mask[];
+};
+
+static struct hw_consumer_buffer *iio_buffer_to_hw_consumer_buffer(
+	struct iio_buffer *buffer)
+{
+	return container_of(buffer, struct hw_consumer_buffer, buffer);
+}
+
+static void iio_hw_buf_release(struct iio_buffer *buffer)
+{
+	struct hw_consumer_buffer *hw_buf =
+		iio_buffer_to_hw_consumer_buffer(buffer);
+	kfree(hw_buf);
+}
+
+static const struct iio_buffer_access_funcs iio_hw_buf_access = {
+	.release = &iio_hw_buf_release,
+	.modes = INDIO_BUFFER_HARDWARE,
+};
+
+static struct hw_consumer_buffer *iio_hw_consumer_get_buffer(
+	struct iio_hw_consumer *hwc, struct iio_dev *indio_dev)
+{
+	size_t mask_size = BITS_TO_LONGS(indio_dev->masklength) * sizeof(long);
+	struct hw_consumer_buffer *buf;
+
+	list_for_each_entry(buf, &hwc->buffers, head) {
+		if (buf->indio_dev == indio_dev)
+			return buf;
+	}
+
+	buf = kzalloc(sizeof(*buf) + mask_size, GFP_KERNEL);
+	if (!buf)
+		return NULL;
+
+	buf->buffer.access = &iio_hw_buf_access;
+	buf->indio_dev = indio_dev;
+	buf->buffer.scan_mask = buf->scan_mask;
+
+	iio_buffer_init(&buf->buffer);
+	list_add_tail(&buf->head, &hwc->buffers);
+
+	return buf;
+}
+
+/**
+ * iio_hw_consumer_alloc() - Allocate IIO hardware consumer
+ * @dev: Pointer to consumer device.
+ *
+ * Returns a valid iio_hw_consumer on success or a ERR_PTR() on failure.
+ */
+struct iio_hw_consumer *iio_hw_consumer_alloc(struct device *dev)
+{
+	struct hw_consumer_buffer *buf;
+	struct iio_hw_consumer *hwc;
+	struct iio_channel *chan;
+	int ret;
+
+	hwc = kzalloc(sizeof(*hwc), GFP_KERNEL);
+	if (!hwc)
+		return ERR_PTR(-ENOMEM);
+
+	INIT_LIST_HEAD(&hwc->buffers);
+
+	hwc->channels = iio_channel_get_all(dev);
+	if (IS_ERR(hwc->channels)) {
+		ret = PTR_ERR(hwc->channels);
+		goto err_free_hwc;
+	}
+
+	chan = &hwc->channels[0];
+	while (chan->indio_dev) {
+		buf = iio_hw_consumer_get_buffer(hwc, chan->indio_dev);
+		if (!buf) {
+			ret = -ENOMEM;
+			goto err_put_buffers;
+		}
+		set_bit(chan->channel->scan_index, buf->buffer.scan_mask);
+		chan++;
+	}
+
+	return hwc;
+
+err_put_buffers:
+	list_for_each_entry(buf, &hwc->buffers, head)
+		iio_buffer_put(&buf->buffer);
+	iio_channel_release_all(hwc->channels);
+err_free_hwc:
+	kfree(hwc);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(iio_hw_consumer_alloc);
+
+/**
+ * iio_hw_consumer_free() - Free IIO hardware consumer
+ * @hwc: hw consumer to free.
+ */
+void iio_hw_consumer_free(struct iio_hw_consumer *hwc)
+{
+	struct hw_consumer_buffer *buf, *n;
+
+	iio_channel_release_all(hwc->channels);
+	list_for_each_entry_safe(buf, n, &hwc->buffers, head)
+		iio_buffer_put(&buf->buffer);
+	kfree(hwc);
+}
+EXPORT_SYMBOL_GPL(iio_hw_consumer_free);
+
+static void devm_iio_hw_consumer_release(struct device *dev, void *res)
+{
+	iio_hw_consumer_free(*(struct iio_hw_consumer **)res);
+}
+
+static int devm_iio_hw_consumer_match(struct device *dev, void *res, void *data)
+{
+	struct iio_hw_consumer **r = res;
+
+	if (!r || !*r) {
+		WARN_ON(!r || !*r);
+		return 0;
+	}
+	return *r == data;
+}
+
+/**
+ * devm_iio_hw_consumer_alloc - Resource-managed iio_hw_consumer_alloc()
+ * @dev: Pointer to consumer device.
+ *
+ * Managed iio_hw_consumer_alloc. iio_hw_consumer allocated with this function
+ * is automatically freed on driver detach.
+ *
+ * If an iio_hw_consumer allocated with this function needs to be freed
+ * separately, devm_iio_hw_consumer_free() must be used.
+ *
+ * returns pointer to allocated iio_hw_consumer on success, NULL on failure.
+ */
+struct iio_hw_consumer *devm_iio_hw_consumer_alloc(struct device *dev)
+{
+	struct iio_hw_consumer **ptr, *iio_hwc;
+
+	ptr = devres_alloc(devm_iio_hw_consumer_release, sizeof(*ptr),
+			   GFP_KERNEL);
+	if (!ptr)
+		return NULL;
+
+	iio_hwc = iio_hw_consumer_alloc(dev);
+	if (IS_ERR(iio_hwc)) {
+		devres_free(ptr);
+	} else {
+		*ptr = iio_hwc;
+		devres_add(dev, ptr);
+	}
+
+	return iio_hwc;
+}
+EXPORT_SYMBOL_GPL(devm_iio_hw_consumer_alloc);
+
+/**
+ * devm_iio_hw_consumer_free - Resource-managed iio_hw_consumer_free()
+ * @dev: Pointer to consumer device.
+ * @hwc: iio_hw_consumer to free.
+ *
+ * Free iio_hw_consumer allocated with devm_iio_hw_consumer_alloc().
+ */
+void devm_iio_hw_consumer_free(struct device *dev, struct iio_hw_consumer *hwc)
+{
+	int rc;
+
+	rc = devres_release(dev, devm_iio_hw_consumer_release,
+			    devm_iio_hw_consumer_match, hwc);
+	WARN_ON(rc);
+}
+EXPORT_SYMBOL_GPL(devm_iio_hw_consumer_free);
+
+/**
+ * iio_hw_consumer_enable() - Enable IIO hardware consumer
+ * @hwc: iio_hw_consumer to enable.
+ *
+ * Returns 0 on success.
+ */
+int iio_hw_consumer_enable(struct iio_hw_consumer *hwc)
+{
+	struct hw_consumer_buffer *buf;
+	int ret;
+
+	list_for_each_entry(buf, &hwc->buffers, head) {
+		ret = iio_update_buffers(buf->indio_dev, &buf->buffer, NULL);
+		if (ret)
+			goto err_disable_buffers;
+	}
+
+	return 0;
+
+err_disable_buffers:
+	list_for_each_entry_continue_reverse(buf, &hwc->buffers, head)
+		iio_update_buffers(buf->indio_dev, NULL, &buf->buffer);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(iio_hw_consumer_enable);
+
+/**
+ * iio_hw_consumer_disable() - Disable IIO hardware consumer
+ * @hwc: iio_hw_consumer to disable.
+ */
+void iio_hw_consumer_disable(struct iio_hw_consumer *hwc)
+{
+	struct hw_consumer_buffer *buf;
+
+	list_for_each_entry(buf, &hwc->buffers, head)
+		iio_update_buffers(buf->indio_dev, NULL, &buf->buffer);
+}
+EXPORT_SYMBOL_GPL(iio_hw_consumer_disable);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("Hardware consumer buffer the IIO framework");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
index 069defcc6d9b..ec98790e2a28 100644
--- a/drivers/iio/inkern.c
+++ b/drivers/iio/inkern.c
@@ -664,9 +664,8 @@ err_unlock:
 }
 EXPORT_SYMBOL_GPL(iio_convert_raw_to_processed);
 
-static int iio_read_channel_attribute(struct iio_channel *chan,
-				      int *val, int *val2,
-				      enum iio_chan_info_enum attribute)
+int iio_read_channel_attribute(struct iio_channel *chan, int *val, int *val2,
+			       enum iio_chan_info_enum attribute)
 {
 	int ret;
 
@@ -682,6 +681,7 @@ err_unlock:
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(iio_read_channel_attribute);
 
 int iio_read_channel_offset(struct iio_channel *chan, int *val, int *val2)
 {
@@ -850,7 +850,8 @@ static int iio_channel_write(struct iio_channel *chan, int val, int val2,
 						chan->channel, val, val2, info);
 }
 
-int iio_write_channel_raw(struct iio_channel *chan, int val)
+int iio_write_channel_attribute(struct iio_channel *chan, int val, int val2,
+				enum iio_chan_info_enum attribute)
 {
 	int ret;
 
@@ -860,12 +861,18 @@ int iio_write_channel_raw(struct iio_channel *chan, int val)
 		goto err_unlock;
 	}
 
-	ret = iio_channel_write(chan, val, 0, IIO_CHAN_INFO_RAW);
+	ret = iio_channel_write(chan, val, val2, attribute);
 err_unlock:
 	mutex_unlock(&chan->indio_dev->info_exist_lock);
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(iio_write_channel_attribute);
+
+int iio_write_channel_raw(struct iio_channel *chan, int val)
+{
+	return iio_write_channel_attribute(chan, val, 0, IIO_CHAN_INFO_RAW);
+}
 EXPORT_SYMBOL_GPL(iio_write_channel_raw);
 
 unsigned int iio_get_channel_ext_info_count(struct iio_channel *chan)