1 files changed, 701 insertions, 61 deletions

diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
index c28e7ff80e11..5bfcc1f13105 100644
--- a/drivers/iio/adc/stm32-adc.c
+++ b/drivers/iio/adc/stm32-adc.c
@@ -31,9 +31,11 @@
 #include <linux/iio/triggered_buffer.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 
 #include "stm32-adc-core.h"
 
@@ -76,6 +78,78 @@
 #define STM32F4_DMA			BIT(8)
 #define STM32F4_ADON			BIT(0)
 
+/* STM32H7 - Registers for each ADC instance */
+#define STM32H7_ADC_ISR			0x00
+#define STM32H7_ADC_IER			0x04
+#define STM32H7_ADC_CR			0x08
+#define STM32H7_ADC_CFGR		0x0C
+#define STM32H7_ADC_PCSEL		0x1C
+#define STM32H7_ADC_SQR1		0x30
+#define STM32H7_ADC_SQR2		0x34
+#define STM32H7_ADC_SQR3		0x38
+#define STM32H7_ADC_SQR4		0x3C
+#define STM32H7_ADC_DR			0x40
+#define STM32H7_ADC_CALFACT		0xC4
+#define STM32H7_ADC_CALFACT2		0xC8
+
+/* STM32H7_ADC_ISR - bit fields */
+#define STM32H7_EOC			BIT(2)
+#define STM32H7_ADRDY			BIT(0)
+
+/* STM32H7_ADC_IER - bit fields */
+#define STM32H7_EOCIE			STM32H7_EOC
+
+/* STM32H7_ADC_CR - bit fields */
+#define STM32H7_ADCAL			BIT(31)
+#define STM32H7_ADCALDIF		BIT(30)
+#define STM32H7_DEEPPWD			BIT(29)
+#define STM32H7_ADVREGEN		BIT(28)
+#define STM32H7_LINCALRDYW6		BIT(27)
+#define STM32H7_LINCALRDYW5		BIT(26)
+#define STM32H7_LINCALRDYW4		BIT(25)
+#define STM32H7_LINCALRDYW3		BIT(24)
+#define STM32H7_LINCALRDYW2		BIT(23)
+#define STM32H7_LINCALRDYW1		BIT(22)
+#define STM32H7_ADCALLIN		BIT(16)
+#define STM32H7_BOOST			BIT(8)
+#define STM32H7_ADSTP			BIT(4)
+#define STM32H7_ADSTART			BIT(2)
+#define STM32H7_ADDIS			BIT(1)
+#define STM32H7_ADEN			BIT(0)
+
+/* STM32H7_ADC_CFGR bit fields */
+#define STM32H7_EXTEN_SHIFT		10
+#define STM32H7_EXTEN_MASK		GENMASK(11, 10)
+#define STM32H7_EXTSEL_SHIFT		5
+#define STM32H7_EXTSEL_MASK		GENMASK(9, 5)
+#define STM32H7_RES_SHIFT		2
+#define STM32H7_RES_MASK		GENMASK(4, 2)
+#define STM32H7_DMNGT_SHIFT		0
+#define STM32H7_DMNGT_MASK		GENMASK(1, 0)
+
+enum stm32h7_adc_dmngt {
+	STM32H7_DMNGT_DR_ONLY,		/* Regular data in DR only */
+	STM32H7_DMNGT_DMA_ONESHOT,	/* DMA one shot mode */
+	STM32H7_DMNGT_DFSDM,		/* DFSDM mode */
+	STM32H7_DMNGT_DMA_CIRC,		/* DMA circular mode */
+};
+
+/* STM32H7_ADC_CALFACT - bit fields */
+#define STM32H7_CALFACT_D_SHIFT		16
+#define STM32H7_CALFACT_D_MASK		GENMASK(26, 16)
+#define STM32H7_CALFACT_S_SHIFT		0
+#define STM32H7_CALFACT_S_MASK		GENMASK(10, 0)
+
+/* STM32H7_ADC_CALFACT2 - bit fields */
+#define STM32H7_LINCALFACT_SHIFT	0
+#define STM32H7_LINCALFACT_MASK		GENMASK(29, 0)
+
+/* Number of linear calibration shadow registers / LINCALRDYW control bits */
+#define STM32H7_LINCALFACT_NUM		6
+
+/* BOOST bit must be set on STM32H7 when ADC clock is above 20MHz */
+#define STM32H7_BOOST_CLKRATE		20000000UL
+
 #define STM32_ADC_MAX_SQ		16	/* SQ1..SQ16 */
 #define STM32_ADC_TIMEOUT_US		100000
 #define STM32_ADC_TIMEOUT	(msecs_to_jiffies(STM32_ADC_TIMEOUT_US / 1000))
@@ -121,6 +195,18 @@ struct stm32_adc_trig_info {
 };
 
 /**
+ * struct stm32_adc_calib - optional adc calibration data
+ * @calfact_s: Calibration offset for single ended channels
+ * @calfact_d: Calibration offset in differential
+ * @lincalfact: Linearity calibration factor
+ */
+struct stm32_adc_calib {
+	u32			calfact_s;
+	u32			calfact_d;
+	u32			lincalfact[STM32H7_LINCALFACT_NUM];
+};
+
+/**
  * stm32_adc_regs - stm32 ADC misc registers & bitfield desc
  * @reg:		register offset
  * @mask:		bitfield mask
@@ -133,9 +219,56 @@ struct stm32_adc_regs {
 };
 
 /**
+ * stm32_adc_regspec - stm32 registers definition, compatible dependent data
+ * @dr:			data register offset
+ * @ier_eoc:		interrupt enable register & eocie bitfield
+ * @isr_eoc:		interrupt status register & eoc bitfield
+ * @sqr:		reference to sequence registers array
+ * @exten:		trigger control register & bitfield
+ * @extsel:		trigger selection register & bitfield
+ * @res:		resolution selection register & bitfield
+ */
+struct stm32_adc_regspec {
+	const u32 dr;
+	const struct stm32_adc_regs ier_eoc;
+	const struct stm32_adc_regs isr_eoc;
+	const struct stm32_adc_regs *sqr;
+	const struct stm32_adc_regs exten;
+	const struct stm32_adc_regs extsel;
+	const struct stm32_adc_regs res;
+};
+
+struct stm32_adc;
+
+/**
+ * stm32_adc_cfg - stm32 compatible configuration data
+ * @regs:		registers descriptions
+ * @adc_info:		per instance input channels definitions
+ * @trigs:		external trigger sources
+ * @clk_required:	clock is required
+ * @selfcalib:		optional routine for self-calibration
+ * @prepare:		optional prepare routine (power-up, enable)
+ * @start_conv:		routine to start conversions
+ * @stop_conv:		routine to stop conversions
+ * @unprepare:		optional unprepare routine (disable, power-down)
+ */
+struct stm32_adc_cfg {
+	const struct stm32_adc_regspec	*regs;
+	const struct stm32_adc_info	*adc_info;
+	struct stm32_adc_trig_info	*trigs;
+	bool clk_required;
+	int (*selfcalib)(struct stm32_adc *);
+	int (*prepare)(struct stm32_adc *);
+	void (*start_conv)(struct stm32_adc *, bool dma);
+	void (*stop_conv)(struct stm32_adc *);
+	void (*unprepare)(struct stm32_adc *);
+};
+
+/**
  * struct stm32_adc - private data of each ADC IIO instance
  * @common:		reference to ADC block common data
  * @offset:		ADC instance register offset in ADC block
+ * @cfg:		compatible configuration data
  * @completion:		end of single conversion completion
  * @buffer:		data buffer
  * @clk:		clock for this adc instance
@@ -149,10 +282,13 @@ struct stm32_adc_regs {
  * @rx_buf:		dma rx buffer cpu address
  * @rx_dma_buf:		dma rx buffer bus address
  * @rx_buf_sz:		dma rx buffer size
+ * @pcsel		bitmask to preselect channels on some devices
+ * @cal:		optional calibration data on some devices
  */
 struct stm32_adc {
 	struct stm32_adc_common	*common;
 	u32			offset;
+	const struct stm32_adc_cfg	*cfg;
 	struct completion	completion;
 	u16			buffer[STM32_ADC_MAX_SQ];
 	struct clk		*clk;
@@ -166,6 +302,8 @@ struct stm32_adc {
 	u8			*rx_buf;
 	dma_addr_t		rx_dma_buf;
 	unsigned int		rx_buf_sz;
+	u32			pcsel;
+	struct stm32_adc_calib	cal;
 };
 
 /**
@@ -180,8 +318,26 @@ struct stm32_adc_chan_spec {
 	const char		*name;
 };
 
-/* Input definitions common for all STM32F4 instances */
-static const struct stm32_adc_chan_spec stm32f4_adc123_channels[] = {
+/**
+ * struct stm32_adc_info - stm32 ADC, per instance config data
+ * @channels:		Reference to stm32 channels spec
+ * @max_channels:	Number of channels
+ * @resolutions:	available resolutions
+ * @num_res:		number of available resolutions
+ */
+struct stm32_adc_info {
+	const struct stm32_adc_chan_spec *channels;
+	int max_channels;
+	const unsigned int *resolutions;
+	const unsigned int num_res;
+};
+
+/*
+ * Input definitions common for all instances:
+ * stm32f4 can have up to 16 channels
+ * stm32h7 can have up to 20 channels
+ */
+static const struct stm32_adc_chan_spec stm32_adc_channels[] = {
 	{ IIO_VOLTAGE, 0, "in0" },
 	{ IIO_VOLTAGE, 1, "in1" },
 	{ IIO_VOLTAGE, 2, "in2" },
@@ -198,6 +354,10 @@ static const struct stm32_adc_chan_spec stm32f4_adc123_channels[] = {
 	{ IIO_VOLTAGE, 13, "in13" },
 	{ IIO_VOLTAGE, 14, "in14" },
 	{ IIO_VOLTAGE, 15, "in15" },
+	{ IIO_VOLTAGE, 16, "in16" },
+	{ IIO_VOLTAGE, 17, "in17" },
+	{ IIO_VOLTAGE, 18, "in18" },
+	{ IIO_VOLTAGE, 19, "in19" },
 };
 
 static const unsigned int stm32f4_adc_resolutions[] = {
@@ -205,6 +365,25 @@ static const unsigned int stm32f4_adc_resolutions[] = {
 	12, 10, 8, 6,
 };
 
+static const struct stm32_adc_info stm32f4_adc_info = {
+	.channels = stm32_adc_channels,
+	.max_channels = 16,
+	.resolutions = stm32f4_adc_resolutions,
+	.num_res = ARRAY_SIZE(stm32f4_adc_resolutions),
+};
+
+static const unsigned int stm32h7_adc_resolutions[] = {
+	/* sorted values so the index matches RES[2:0] in STM32H7_ADC_CFGR */
+	16, 14, 12, 10, 8,
+};
+
+static const struct stm32_adc_info stm32h7_adc_info = {
+	.channels = stm32_adc_channels,
+	.max_channels = 20,
+	.resolutions = stm32h7_adc_resolutions,
+	.num_res = ARRAY_SIZE(stm32h7_adc_resolutions),
+};
+
 /**
  * stm32f4_sq - describe regular sequence registers
  * - L: sequence len (register & bit field)
@@ -252,6 +431,69 @@ static struct stm32_adc_trig_info stm32f4_adc_trigs[] = {
 	{}, /* sentinel */
 };
 
+static const struct stm32_adc_regspec stm32f4_adc_regspec = {
+	.dr = STM32F4_ADC_DR,
+	.ier_eoc = { STM32F4_ADC_CR1, STM32F4_EOCIE },
+	.isr_eoc = { STM32F4_ADC_SR, STM32F4_EOC },
+	.sqr = stm32f4_sq,
+	.exten = { STM32F4_ADC_CR2, STM32F4_EXTEN_MASK, STM32F4_EXTEN_SHIFT },
+	.extsel = { STM32F4_ADC_CR2, STM32F4_EXTSEL_MASK,
+		    STM32F4_EXTSEL_SHIFT },
+	.res = { STM32F4_ADC_CR1, STM32F4_RES_MASK, STM32F4_RES_SHIFT },
+};
+
+static const struct stm32_adc_regs stm32h7_sq[STM32_ADC_MAX_SQ + 1] = {
+	/* L: len bit field description to be kept as first element */
+	{ STM32H7_ADC_SQR1, GENMASK(3, 0), 0 },
+	/* SQ1..SQ16 registers & bit fields (reg, mask, shift) */
+	{ STM32H7_ADC_SQR1, GENMASK(10, 6), 6 },
+	{ STM32H7_ADC_SQR1, GENMASK(16, 12), 12 },
+	{ STM32H7_ADC_SQR1, GENMASK(22, 18), 18 },
+	{ STM32H7_ADC_SQR1, GENMASK(28, 24), 24 },
+	{ STM32H7_ADC_SQR2, GENMASK(4, 0), 0 },
+	{ STM32H7_ADC_SQR2, GENMASK(10, 6), 6 },
+	{ STM32H7_ADC_SQR2, GENMASK(16, 12), 12 },
+	{ STM32H7_ADC_SQR2, GENMASK(22, 18), 18 },
+	{ STM32H7_ADC_SQR2, GENMASK(28, 24), 24 },
+	{ STM32H7_ADC_SQR3, GENMASK(4, 0), 0 },
+	{ STM32H7_ADC_SQR3, GENMASK(10, 6), 6 },
+	{ STM32H7_ADC_SQR3, GENMASK(16, 12), 12 },
+	{ STM32H7_ADC_SQR3, GENMASK(22, 18), 18 },
+	{ STM32H7_ADC_SQR3, GENMASK(28, 24), 24 },
+	{ STM32H7_ADC_SQR4, GENMASK(4, 0), 0 },
+	{ STM32H7_ADC_SQR4, GENMASK(10, 6), 6 },
+};
+
+/* STM32H7 external trigger sources for all instances */
+static struct stm32_adc_trig_info stm32h7_adc_trigs[] = {
+	{ TIM1_CH1, STM32_EXT0 },
+	{ TIM1_CH2, STM32_EXT1 },
+	{ TIM1_CH3, STM32_EXT2 },
+	{ TIM2_CH2, STM32_EXT3 },
+	{ TIM3_TRGO, STM32_EXT4 },
+	{ TIM4_CH4, STM32_EXT5 },
+	{ TIM8_TRGO, STM32_EXT7 },
+	{ TIM8_TRGO2, STM32_EXT8 },
+	{ TIM1_TRGO, STM32_EXT9 },
+	{ TIM1_TRGO2, STM32_EXT10 },
+	{ TIM2_TRGO, STM32_EXT11 },
+	{ TIM4_TRGO, STM32_EXT12 },
+	{ TIM6_TRGO, STM32_EXT13 },
+	{ TIM3_CH4, STM32_EXT15 },
+	{},
+};
+
+static const struct stm32_adc_regspec stm32h7_adc_regspec = {
+	.dr = STM32H7_ADC_DR,
+	.ier_eoc = { STM32H7_ADC_IER, STM32H7_EOCIE },
+	.isr_eoc = { STM32H7_ADC_ISR, STM32H7_EOC },
+	.sqr = stm32h7_sq,
+	.exten = { STM32H7_ADC_CFGR, STM32H7_EXTEN_MASK, STM32H7_EXTEN_SHIFT },
+	.extsel = { STM32H7_ADC_CFGR, STM32H7_EXTSEL_MASK,
+		    STM32H7_EXTSEL_SHIFT },
+	.res = { STM32H7_ADC_CFGR, STM32H7_RES_MASK, STM32H7_RES_SHIFT },
+};
+
 /**
  * STM32 ADC registers access routines
  * @adc: stm32 adc instance
@@ -265,6 +507,12 @@ static u32 stm32_adc_readl(struct stm32_adc *adc, u32 reg)
 	return readl_relaxed(adc->common->base + adc->offset + reg);
 }
 
+#define stm32_adc_readl_addr(addr)	stm32_adc_readl(adc, addr)
+
+#define stm32_adc_readl_poll_timeout(reg, val, cond, sleep_us, timeout_us) \
+	readx_poll_timeout(stm32_adc_readl_addr, reg, val, \
+			   cond, sleep_us, timeout_us)
+
 static u16 stm32_adc_readw(struct stm32_adc *adc, u32 reg)
 {
 	return readw_relaxed(adc->common->base + adc->offset + reg);
@@ -299,7 +547,8 @@ static void stm32_adc_clr_bits(struct stm32_adc *adc, u32 reg, u32 bits)
  */
 static void stm32_adc_conv_irq_enable(struct stm32_adc *adc)
 {
-	stm32_adc_set_bits(adc, STM32F4_ADC_CR1, STM32F4_EOCIE);
+	stm32_adc_set_bits(adc, adc->cfg->regs->ier_eoc.reg,
+			   adc->cfg->regs->ier_eoc.mask);
 };
 
 /**
@@ -308,19 +557,22 @@ static void stm32_adc_conv_irq_enable(struct stm32_adc *adc)
  */
 static void stm32_adc_conv_irq_disable(struct stm32_adc *adc)
 {
-	stm32_adc_clr_bits(adc, STM32F4_ADC_CR1, STM32F4_EOCIE);
+	stm32_adc_clr_bits(adc, adc->cfg->regs->ier_eoc.reg,
+			   adc->cfg->regs->ier_eoc.mask);
 }
 
 static void stm32_adc_set_res(struct stm32_adc *adc)
 {
-	u32 val = stm32_adc_readl(adc, STM32F4_ADC_CR1);
+	const struct stm32_adc_regs *res = &adc->cfg->regs->res;
+	u32 val;
 
-	val = (val & ~STM32F4_RES_MASK) | (adc->res << STM32F4_RES_SHIFT);
-	stm32_adc_writel(adc, STM32F4_ADC_CR1, val);
+	val = stm32_adc_readl(adc, res->reg);
+	val = (val & ~res->mask) | (adc->res << res->shift);
+	stm32_adc_writel(adc, res->reg, val);
 }
 
 /**
- * stm32_adc_start_conv() - Start conversions for regular channels.
+ * stm32f4_adc_start_conv() - Start conversions for regular channels.
  * @adc: stm32 adc instance
  * @dma: use dma to transfer conversion result
  *
@@ -329,7 +581,7 @@ static void stm32_adc_set_res(struct stm32_adc *adc)
  * conversions, in IIO buffer modes. Otherwise, use ADC interrupt with direct
  * DR read instead (e.g. read_raw, or triggered buffer mode without DMA).
  */
-static void stm32_adc_start_conv(struct stm32_adc *adc, bool dma)
+static void stm32f4_adc_start_conv(struct stm32_adc *adc, bool dma)
 {
 	stm32_adc_set_bits(adc, STM32F4_ADC_CR1, STM32F4_SCAN);
 
@@ -347,7 +599,7 @@ static void stm32_adc_start_conv(struct stm32_adc *adc, bool dma)
 		stm32_adc_set_bits(adc, STM32F4_ADC_CR2, STM32F4_SWSTART);
 }
 
-static void stm32_adc_stop_conv(struct stm32_adc *adc)
+static void stm32f4_adc_stop_conv(struct stm32_adc *adc)
 {
 	stm32_adc_clr_bits(adc, STM32F4_ADC_CR2, STM32F4_EXTEN_MASK);
 	stm32_adc_clr_bits(adc, STM32F4_ADC_SR, STM32F4_STRT);
@@ -357,6 +609,324 @@ static void stm32_adc_stop_conv(struct stm32_adc *adc)
 			   STM32F4_ADON | STM32F4_DMA | STM32F4_DDS);
 }
 
+static void stm32h7_adc_start_conv(struct stm32_adc *adc, bool dma)
+{
+	enum stm32h7_adc_dmngt dmngt;
+	unsigned long flags;
+	u32 val;
+
+	if (dma)
+		dmngt = STM32H7_DMNGT_DMA_CIRC;
+	else
+		dmngt = STM32H7_DMNGT_DR_ONLY;
+
+	spin_lock_irqsave(&adc->lock, flags);
+	val = stm32_adc_readl(adc, STM32H7_ADC_CFGR);
+	val = (val & ~STM32H7_DMNGT_MASK) | (dmngt << STM32H7_DMNGT_SHIFT);
+	stm32_adc_writel(adc, STM32H7_ADC_CFGR, val);
+	spin_unlock_irqrestore(&adc->lock, flags);
+
+	stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADSTART);
+}
+
+static void stm32h7_adc_stop_conv(struct stm32_adc *adc)
+{
+	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+	int ret;
+	u32 val;
+
+	stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADSTP);
+
+	ret = stm32_adc_readl_poll_timeout(STM32H7_ADC_CR, val,
+					   !(val & (STM32H7_ADSTART)),
+					   100, STM32_ADC_TIMEOUT_US);
+	if (ret)
+		dev_warn(&indio_dev->dev, "stop failed\n");
+
+	stm32_adc_clr_bits(adc, STM32H7_ADC_CFGR, STM32H7_DMNGT_MASK);
+}
+
+static void stm32h7_adc_exit_pwr_down(struct stm32_adc *adc)
+{
+	/* Exit deep power down, then enable ADC voltage regulator */
+	stm32_adc_clr_bits(adc, STM32H7_ADC_CR, STM32H7_DEEPPWD);
+	stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADVREGEN);
+
+	if (adc->common->rate > STM32H7_BOOST_CLKRATE)
+		stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_BOOST);
+
+	/* Wait for startup time */
+	usleep_range(10, 20);
+}
+
+static void stm32h7_adc_enter_pwr_down(struct stm32_adc *adc)
+{
+	stm32_adc_clr_bits(adc, STM32H7_ADC_CR, STM32H7_BOOST);
+
+	/* Setting DEEPPWD disables ADC vreg and clears ADVREGEN */
+	stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_DEEPPWD);
+}
+
+static int stm32h7_adc_enable(struct stm32_adc *adc)
+{
+	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+	int ret;
+	u32 val;
+
+	/* Clear ADRDY by writing one, then enable ADC */
+	stm32_adc_set_bits(adc, STM32H7_ADC_ISR, STM32H7_ADRDY);
+	stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADEN);
+
+	/* Poll for ADRDY to be set (after adc startup time) */
+	ret = stm32_adc_readl_poll_timeout(STM32H7_ADC_ISR, val,
+					   val & STM32H7_ADRDY,
+					   100, STM32_ADC_TIMEOUT_US);
+	if (ret) {
+		stm32_adc_clr_bits(adc, STM32H7_ADC_CR, STM32H7_ADEN);
+		dev_err(&indio_dev->dev, "Failed to enable ADC\n");
+	}
+
+	return ret;
+}
+
+static void stm32h7_adc_disable(struct stm32_adc *adc)
+{
+	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+	int ret;
+	u32 val;
+
+	/* Disable ADC and wait until it's effectively disabled */
+	stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADDIS);
+	ret = stm32_adc_readl_poll_timeout(STM32H7_ADC_CR, val,
+					   !(val & STM32H7_ADEN), 100,
+					   STM32_ADC_TIMEOUT_US);
+	if (ret)
+		dev_warn(&indio_dev->dev, "Failed to disable\n");
+}
+
+/**
+ * stm32h7_adc_read_selfcalib() - read calibration shadow regs, save result
+ * @adc: stm32 adc instance
+ */
+static int stm32h7_adc_read_selfcalib(struct stm32_adc *adc)
+{
+	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+	int i, ret;
+	u32 lincalrdyw_mask, val;
+
+	/* Enable adc so LINCALRDYW1..6 bits are writable */
+	ret = stm32h7_adc_enable(adc);
+	if (ret)
+		return ret;
+
+	/* Read linearity calibration */
+	lincalrdyw_mask = STM32H7_LINCALRDYW6;
+	for (i = STM32H7_LINCALFACT_NUM - 1; i >= 0; i--) {
+		/* Clear STM32H7_LINCALRDYW[6..1]: transfer calib to CALFACT2 */
+		stm32_adc_clr_bits(adc, STM32H7_ADC_CR, lincalrdyw_mask);
+
+		/* Poll: wait calib data to be ready in CALFACT2 register */
+		ret = stm32_adc_readl_poll_timeout(STM32H7_ADC_CR, val,
+						   !(val & lincalrdyw_mask),
+						   100, STM32_ADC_TIMEOUT_US);
+		if (ret) {
+			dev_err(&indio_dev->dev, "Failed to read calfact\n");
+			goto disable;
+		}
+
+		val = stm32_adc_readl(adc, STM32H7_ADC_CALFACT2);
+		adc->cal.lincalfact[i] = (val & STM32H7_LINCALFACT_MASK);
+		adc->cal.lincalfact[i] >>= STM32H7_LINCALFACT_SHIFT;
+
+		lincalrdyw_mask >>= 1;
+	}
+
+	/* Read offset calibration */
+	val = stm32_adc_readl(adc, STM32H7_ADC_CALFACT);
+	adc->cal.calfact_s = (val & STM32H7_CALFACT_S_MASK);
+	adc->cal.calfact_s >>= STM32H7_CALFACT_S_SHIFT;
+	adc->cal.calfact_d = (val & STM32H7_CALFACT_D_MASK);
+	adc->cal.calfact_d >>= STM32H7_CALFACT_D_SHIFT;
+
+disable:
+	stm32h7_adc_disable(adc);
+
+	return ret;
+}
+
+/**
+ * stm32h7_adc_restore_selfcalib() - Restore saved self-calibration result
+ * @adc: stm32 adc instance
+ * Note: ADC must be enabled, with no on-going conversions.
+ */
+static int stm32h7_adc_restore_selfcalib(struct stm32_adc *adc)
+{
+	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+	int i, ret;
+	u32 lincalrdyw_mask, val;
+
+	val = (adc->cal.calfact_s << STM32H7_CALFACT_S_SHIFT) |
+		(adc->cal.calfact_d << STM32H7_CALFACT_D_SHIFT);
+	stm32_adc_writel(adc, STM32H7_ADC_CALFACT, val);
+
+	lincalrdyw_mask = STM32H7_LINCALRDYW6;
+	for (i = STM32H7_LINCALFACT_NUM - 1; i >= 0; i--) {
+		/*
+		 * Write saved calibration data to shadow registers:
+		 * Write CALFACT2, and set LINCALRDYW[6..1] bit to trigger
+		 * data write. Then poll to wait for complete transfer.
+		 */
+		val = adc->cal.lincalfact[i] << STM32H7_LINCALFACT_SHIFT;
+		stm32_adc_writel(adc, STM32H7_ADC_CALFACT2, val);
+		stm32_adc_set_bits(adc, STM32H7_ADC_CR, lincalrdyw_mask);
+		ret = stm32_adc_readl_poll_timeout(STM32H7_ADC_CR, val,
+						   val & lincalrdyw_mask,
+						   100, STM32_ADC_TIMEOUT_US);
+		if (ret) {
+			dev_err(&indio_dev->dev, "Failed to write calfact\n");
+			return ret;
+		}
+
+		/*
+		 * Read back calibration data, has two effects:
+		 * - It ensures bits LINCALRDYW[6..1] are kept cleared
+		 *   for next time calibration needs to be restored.
+		 * - BTW, bit clear triggers a read, then check data has been
+		 *   correctly written.
+		 */
+		stm32_adc_clr_bits(adc, STM32H7_ADC_CR, lincalrdyw_mask);
+		ret = stm32_adc_readl_poll_timeout(STM32H7_ADC_CR, val,
+						   !(val & lincalrdyw_mask),
+						   100, STM32_ADC_TIMEOUT_US);
+		if (ret) {
+			dev_err(&indio_dev->dev, "Failed to read calfact\n");
+			return ret;
+		}
+		val = stm32_adc_readl(adc, STM32H7_ADC_CALFACT2);
+		if (val != adc->cal.lincalfact[i] << STM32H7_LINCALFACT_SHIFT) {
+			dev_err(&indio_dev->dev, "calfact not consistent\n");
+			return -EIO;
+		}
+
+		lincalrdyw_mask >>= 1;
+	}
+
+	return 0;
+}
+
+/**
+ * Fixed timeout value for ADC calibration.
+ * worst cases:
+ * - low clock frequency
+ * - maximum prescalers
+ * Calibration requires:
+ * - 131,072 ADC clock cycle for the linear calibration
+ * - 20 ADC clock cycle for the offset calibration
+ *
+ * Set to 100ms for now
+ */
+#define STM32H7_ADC_CALIB_TIMEOUT_US		100000
+
+/**
+ * stm32h7_adc_selfcalib() - Procedure to calibrate ADC (from power down)
+ * @adc: stm32 adc instance
+ * Exit from power down, calibrate ADC, then return to power down.
+ */
+static int stm32h7_adc_selfcalib(struct stm32_adc *adc)
+{
+	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+	int ret;
+	u32 val;
+
+	stm32h7_adc_exit_pwr_down(adc);
+
+	/*
+	 * Select calibration mode:
+	 * - Offset calibration for single ended inputs
+	 * - No linearity calibration (do it later, before reading it)
+	 */
+	stm32_adc_clr_bits(adc, STM32H7_ADC_CR, STM32H7_ADCALDIF);
+	stm32_adc_clr_bits(adc, STM32H7_ADC_CR, STM32H7_ADCALLIN);
+
+	/* Start calibration, then wait for completion */
+	stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADCAL);
+	ret = stm32_adc_readl_poll_timeout(STM32H7_ADC_CR, val,
+					   !(val & STM32H7_ADCAL), 100,
+					   STM32H7_ADC_CALIB_TIMEOUT_US);
+	if (ret) {
+		dev_err(&indio_dev->dev, "calibration failed\n");
+		goto pwr_dwn;
+	}
+
+	/*
+	 * Select calibration mode, then start calibration:
+	 * - Offset calibration for differential input
+	 * - Linearity calibration (needs to be done only once for single/diff)
+	 *   will run simultaneously with offset calibration.
+	 */
+	stm32_adc_set_bits(adc, STM32H7_ADC_CR,
+			   STM32H7_ADCALDIF | STM32H7_ADCALLIN);
+	stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADCAL);
+	ret = stm32_adc_readl_poll_timeout(STM32H7_ADC_CR, val,
+					   !(val & STM32H7_ADCAL), 100,
+					   STM32H7_ADC_CALIB_TIMEOUT_US);
+	if (ret) {
+		dev_err(&indio_dev->dev, "calibration failed\n");
+		goto pwr_dwn;
+	}
+
+	stm32_adc_clr_bits(adc, STM32H7_ADC_CR,
+			   STM32H7_ADCALDIF | STM32H7_ADCALLIN);
+
+	/* Read calibration result for future reference */
+	ret = stm32h7_adc_read_selfcalib(adc);
+
+pwr_dwn:
+	stm32h7_adc_enter_pwr_down(adc);
+
+	return ret;
+}
+
+/**
+ * stm32h7_adc_prepare() - Leave power down mode to enable ADC.
+ * @adc: stm32 adc instance
+ * Leave power down mode.
+ * Enable ADC.
+ * Restore calibration data.
+ * Pre-select channels that may be used in PCSEL (required by input MUX / IO).
+ */
+static int stm32h7_adc_prepare(struct stm32_adc *adc)
+{
+	int ret;
+
+	stm32h7_adc_exit_pwr_down(adc);
+
+	ret = stm32h7_adc_enable(adc);
+	if (ret)
+		goto pwr_dwn;
+
+	ret = stm32h7_adc_restore_selfcalib(adc);
+	if (ret)
+		goto disable;
+
+	stm32_adc_writel(adc, STM32H7_ADC_PCSEL, adc->pcsel);
+
+	return 0;
+
+disable:
+	stm32h7_adc_disable(adc);
+pwr_dwn:
+	stm32h7_adc_enter_pwr_down(adc);
+
+	return ret;
+}
+
+static void stm32h7_adc_unprepare(struct stm32_adc *adc)
+{
+	stm32h7_adc_disable(adc);
+	stm32h7_adc_enter_pwr_down(adc);
+}
+
 /**
  * stm32_adc_conf_scan_seq() - Build regular channels scan sequence
  * @indio_dev: IIO device
@@ -371,6 +941,7 @@ static int stm32_adc_conf_scan_seq(struct iio_dev *indio_dev,
 				   const unsigned long *scan_mask)
 {
 	struct stm32_adc *adc = iio_priv(indio_dev);
+	const struct stm32_adc_regs *sqr = adc->cfg->regs->sqr;
 	const struct iio_chan_spec *chan;
 	u32 val, bit;
 	int i = 0;
@@ -388,20 +959,20 @@ static int stm32_adc_conf_scan_seq(struct iio_dev *indio_dev,
 		dev_dbg(&indio_dev->dev, "%s chan %d to SQ%d\n",
 			__func__, chan->channel, i);
 
-		val = stm32_adc_readl(adc, stm32f4_sq[i].reg);
-		val &= ~stm32f4_sq[i].mask;
-		val |= chan->channel << stm32f4_sq[i].shift;
-		stm32_adc_writel(adc, stm32f4_sq[i].reg, val);
+		val = stm32_adc_readl(adc, sqr[i].reg);
+		val &= ~sqr[i].mask;
+		val |= chan->channel << sqr[i].shift;
+		stm32_adc_writel(adc, sqr[i].reg, val);
 	}
 
 	if (!i)
 		return -EINVAL;
 
 	/* Sequence len */
-	val = stm32_adc_readl(adc, stm32f4_sq[0].reg);
-	val &= ~stm32f4_sq[0].mask;
-	val |= ((i - 1) << stm32f4_sq[0].shift);
-	stm32_adc_writel(adc, stm32f4_sq[0].reg, val);
+	val = stm32_adc_readl(adc, sqr[0].reg);
+	val &= ~sqr[0].mask;
+	val |= ((i - 1) << sqr[0].shift);
+	stm32_adc_writel(adc, sqr[0].reg, val);
 
 	return 0;
 }
@@ -412,19 +983,21 @@ static int stm32_adc_conf_scan_seq(struct iio_dev *indio_dev,
  *
  * Returns trigger extsel value, if trig matches, -EINVAL otherwise.
  */
-static int stm32_adc_get_trig_extsel(struct iio_trigger *trig)
+static int stm32_adc_get_trig_extsel(struct iio_dev *indio_dev,
+				     struct iio_trigger *trig)
 {
+	struct stm32_adc *adc = iio_priv(indio_dev);
 	int i;
 
 	/* lookup triggers registered by stm32 timer trigger driver */
-	for (i = 0; stm32f4_adc_trigs[i].name; i++) {
+	for (i = 0; adc->cfg->trigs[i].name; i++) {
 		/**
 		 * Checking both stm32 timer trigger type and trig name
 		 * should be safe against arbitrary trigger names.
 		 */
 		if (is_stm32_timer_trigger(trig) &&
-		    !strcmp(stm32f4_adc_trigs[i].name, trig->name)) {
-			return stm32f4_adc_trigs[i].extsel;
+		    !strcmp(adc->cfg->trigs[i].name, trig->name)) {
+			return adc->cfg->trigs[i].extsel;
 		}
 	}
 
@@ -449,7 +1022,7 @@ static int stm32_adc_set_trig(struct iio_dev *indio_dev,
 	int ret;
 
 	if (trig) {
-		ret = stm32_adc_get_trig_extsel(trig);
+		ret = stm32_adc_get_trig_extsel(indio_dev, trig);
 		if (ret < 0)
 			return ret;
 
@@ -459,11 +1032,11 @@ static int stm32_adc_set_trig(struct iio_dev *indio_dev,
 	}
 
 	spin_lock_irqsave(&adc->lock, flags);
-	val = stm32_adc_readl(adc, STM32F4_ADC_CR2);
-	val &= ~(STM32F4_EXTEN_MASK | STM32F4_EXTSEL_MASK);
-	val |= exten << STM32F4_EXTEN_SHIFT;
-	val |= extsel << STM32F4_EXTSEL_SHIFT;
-	stm32_adc_writel(adc, STM32F4_ADC_CR2, val);
+	val = stm32_adc_readl(adc, adc->cfg->regs->exten.reg);
+	val &= ~(adc->cfg->regs->exten.mask | adc->cfg->regs->extsel.mask);
+	val |= exten << adc->cfg->regs->exten.shift;
+	val |= extsel << adc->cfg->regs->extsel.shift;
+	stm32_adc_writel(adc,  adc->cfg->regs->exten.reg, val);
 	spin_unlock_irqrestore(&adc->lock, flags);
 
 	return 0;
@@ -515,6 +1088,7 @@ static int stm32_adc_single_conv(struct iio_dev *indio_dev,
 				 int *res)
 {
 	struct stm32_adc *adc = iio_priv(indio_dev);
+	const struct stm32_adc_regspec *regs = adc->cfg->regs;
 	long timeout;
 	u32 val;
 	int ret;
@@ -523,21 +1097,27 @@ static int stm32_adc_single_conv(struct iio_dev *indio_dev,
 
 	adc->bufi = 0;
 
+	if (adc->cfg->prepare) {
+		ret = adc->cfg->prepare(adc);
+		if (ret)
+			return ret;
+	}
+
 	/* Program chan number in regular sequence (SQ1) */
-	val = stm32_adc_readl(adc, stm32f4_sq[1].reg);
-	val &= ~stm32f4_sq[1].mask;
-	val |= chan->channel << stm32f4_sq[1].shift;
-	stm32_adc_writel(adc, stm32f4_sq[1].reg, val);
+	val = stm32_adc_readl(adc, regs->sqr[1].reg);
+	val &= ~regs->sqr[1].mask;
+	val |= chan->channel << regs->sqr[1].shift;
+	stm32_adc_writel(adc, regs->sqr[1].reg, val);
 
 	/* Set regular sequence len (0 for 1 conversion) */
-	stm32_adc_clr_bits(adc, stm32f4_sq[0].reg, stm32f4_sq[0].mask);
+	stm32_adc_clr_bits(adc, regs->sqr[0].reg, regs->sqr[0].mask);
 
 	/* Trigger detection disabled (conversion can be launched in SW) */
-	stm32_adc_clr_bits(adc, STM32F4_ADC_CR2, STM32F4_EXTEN_MASK);
+	stm32_adc_clr_bits(adc, regs->exten.reg, regs->exten.mask);
 
 	stm32_adc_conv_irq_enable(adc);
 
-	stm32_adc_start_conv(adc, false);
+	adc->cfg->start_conv(adc, false);
 
 	timeout = wait_for_completion_interruptible_timeout(
 					&adc->completion, STM32_ADC_TIMEOUT);
@@ -550,10 +1130,13 @@ static int stm32_adc_single_conv(struct iio_dev *indio_dev,
 		ret = IIO_VAL_INT;
 	}
 
-	stm32_adc_stop_conv(adc);
+	adc->cfg->stop_conv(adc);
 
 	stm32_adc_conv_irq_disable(adc);
 
+	if (adc->cfg->unprepare)
+		adc->cfg->unprepare(adc);
+
 	return ret;
 }
 
@@ -590,11 +1173,12 @@ static irqreturn_t stm32_adc_isr(int irq, void *data)
 {
 	struct stm32_adc *adc = data;
 	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
-	u32 status = stm32_adc_readl(adc, STM32F4_ADC_SR);
+	const struct stm32_adc_regspec *regs = adc->cfg->regs;
+	u32 status = stm32_adc_readl(adc, regs->isr_eoc.reg);
 
-	if (status & STM32F4_EOC) {
+	if (status & regs->isr_eoc.mask) {
 		/* Reading DR also clears EOC status flag */
-		adc->buffer[adc->bufi] = stm32_adc_readw(adc, STM32F4_ADC_DR);
+		adc->buffer[adc->bufi] = stm32_adc_readw(adc, regs->dr);
 		if (iio_buffer_enabled(indio_dev)) {
 			adc->bufi++;
 			if (adc->bufi >= adc->num_conv) {
@@ -621,7 +1205,7 @@ static irqreturn_t stm32_adc_isr(int irq, void *data)
 static int stm32_adc_validate_trigger(struct iio_dev *indio_dev,
 				      struct iio_trigger *trig)
 {
-	return stm32_adc_get_trig_extsel(trig) < 0 ? -EINVAL : 0;
+	return stm32_adc_get_trig_extsel(indio_dev, trig) < 0 ? -EINVAL : 0;
 }
 
 static int stm32_adc_set_watermark(struct iio_dev *indio_dev, unsigned int val)
@@ -777,10 +1361,16 @@ static int stm32_adc_buffer_postenable(struct iio_dev *indio_dev)
 	struct stm32_adc *adc = iio_priv(indio_dev);
 	int ret;
 
+	if (adc->cfg->prepare) {
+		ret = adc->cfg->prepare(adc);
+		if (ret)
+			return ret;
+	}
+
 	ret = stm32_adc_set_trig(indio_dev, indio_dev->trig);
 	if (ret) {
 		dev_err(&indio_dev->dev, "Can't set trigger\n");
-		return ret;
+		goto err_unprepare;
 	}
 
 	ret = stm32_adc_dma_start(indio_dev);
@@ -799,7 +1389,7 @@ static int stm32_adc_buffer_postenable(struct iio_dev *indio_dev)
 	if (!adc->dma_chan)
 		stm32_adc_conv_irq_enable(adc);
 
-	stm32_adc_start_conv(adc, !!adc->dma_chan);
+	adc->cfg->start_conv(adc, !!adc->dma_chan);
 
 	return 0;
 
@@ -808,6 +1398,9 @@ err_stop_dma:
 		dmaengine_terminate_all(adc->dma_chan);
 err_clr_trig:
 	stm32_adc_set_trig(indio_dev, NULL);
+err_unprepare:
+	if (adc->cfg->unprepare)
+		adc->cfg->unprepare(adc);
 
 	return ret;
 }
@@ -817,7 +1410,7 @@ static int stm32_adc_buffer_predisable(struct iio_dev *indio_dev)
 	struct stm32_adc *adc = iio_priv(indio_dev);
 	int ret;
 
-	stm32_adc_stop_conv(adc);
+	adc->cfg->stop_conv(adc);
 	if (!adc->dma_chan)
 		stm32_adc_conv_irq_disable(adc);
 
@@ -831,6 +1424,9 @@ static int stm32_adc_buffer_predisable(struct iio_dev *indio_dev)
 	if (stm32_adc_set_trig(indio_dev, NULL))
 		dev_err(&indio_dev->dev, "Can't clear trigger\n");
 
+	if (adc->cfg->unprepare)
+		adc->cfg->unprepare(adc);
+
 	return ret;
 }
 
@@ -895,12 +1491,12 @@ static int stm32_adc_of_get_resolution(struct iio_dev *indio_dev)
 	u32 res;
 
 	if (of_property_read_u32(node, "assigned-resolution-bits", &res))
-		res = stm32f4_adc_resolutions[0];
+		res = adc->cfg->adc_info->resolutions[0];
 
-	for (i = 0; i < ARRAY_SIZE(stm32f4_adc_resolutions); i++)
-		if (res == stm32f4_adc_resolutions[i])
+	for (i = 0; i < adc->cfg->adc_info->num_res; i++)
+		if (res == adc->cfg->adc_info->resolutions[i])
 			break;
-	if (i >= ARRAY_SIZE(stm32f4_adc_resolutions)) {
+	if (i >= adc->cfg->adc_info->num_res) {
 		dev_err(&indio_dev->dev, "Bad resolution: %u bits\n", res);
 		return -EINVAL;
 	}
@@ -926,14 +1522,19 @@ static void stm32_adc_chan_init_one(struct iio_dev *indio_dev,
 	chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
 	chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
 	chan->scan_type.sign = 'u';
-	chan->scan_type.realbits = stm32f4_adc_resolutions[adc->res];
+	chan->scan_type.realbits = adc->cfg->adc_info->resolutions[adc->res];
 	chan->scan_type.storagebits = 16;
 	chan->ext_info = stm32_adc_ext_info;
+
+	/* pre-build selected channels mask */
+	adc->pcsel |= BIT(chan->channel);
 }
 
 static int stm32_adc_chan_of_init(struct iio_dev *indio_dev)
 {
 	struct device_node *node = indio_dev->dev.of_node;
+	struct stm32_adc *adc = iio_priv(indio_dev);
+	const struct stm32_adc_info *adc_info = adc->cfg->adc_info;
 	struct property *prop;
 	const __be32 *cur;
 	struct iio_chan_spec *channels;
@@ -942,7 +1543,7 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev)
 
 	num_channels = of_property_count_u32_elems(node, "st,adc-channels");
 	if (num_channels < 0 ||
-	    num_channels >= ARRAY_SIZE(stm32f4_adc123_channels)) {
+	    num_channels >= adc_info->max_channels) {
 		dev_err(&indio_dev->dev, "Bad st,adc-channels?\n");
 		return num_channels < 0 ? num_channels : -EINVAL;
 	}
@@ -953,12 +1554,12 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev)
 		return -ENOMEM;
 
 	of_property_for_each_u32(node, "st,adc-channels", prop, cur, val) {
-		if (val >= ARRAY_SIZE(stm32f4_adc123_channels)) {
+		if (val >= adc_info->max_channels) {
 			dev_err(&indio_dev->dev, "Invalid channel %d\n", val);
 			return -EINVAL;
 		}
 		stm32_adc_chan_init_one(indio_dev, &channels[scan_index],
-					&stm32f4_adc123_channels[val],
+					&adc_info->channels[val],
 					scan_index);
 		scan_index++;
 	}
@@ -990,7 +1591,7 @@ static int stm32_adc_dma_request(struct iio_dev *indio_dev)
 	/* Configure DMA channel to read data register */
 	memset(&config, 0, sizeof(config));
 	config.src_addr = (dma_addr_t)adc->common->phys_base;
-	config.src_addr += adc->offset + STM32F4_ADC_DR;
+	config.src_addr += adc->offset + adc->cfg->regs->dr;
 	config.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 
 	ret = dmaengine_slave_config(adc->dma_chan, &config);
@@ -1011,6 +1612,7 @@ err_release:
 static int stm32_adc_probe(struct platform_device *pdev)
 {
 	struct iio_dev *indio_dev;
+	struct device *dev = &pdev->dev;
 	struct stm32_adc *adc;
 	int ret;
 
@@ -1025,6 +1627,8 @@ static int stm32_adc_probe(struct platform_device *pdev)
 	adc->common = dev_get_drvdata(pdev->dev.parent);
 	spin_lock_init(&adc->lock);
 	init_completion(&adc->completion);
+	adc->cfg = (const struct stm32_adc_cfg *)
+		of_match_device(dev->driver->of_match_table, dev)->data;
 
 	indio_dev->name = dev_name(&pdev->dev);
 	indio_dev->dev.parent = &pdev->dev;
@@ -1055,14 +1659,21 @@ static int stm32_adc_probe(struct platform_device *pdev)
 
 	adc->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(adc->clk)) {
-		dev_err(&pdev->dev, "Can't get clock\n");
-		return PTR_ERR(adc->clk);
+		ret = PTR_ERR(adc->clk);
+		if (ret == -ENOENT && !adc->cfg->clk_required) {
+			adc->clk = NULL;
+		} else {
+			dev_err(&pdev->dev, "Can't get clock\n");
+			return ret;
+		}
 	}
 
-	ret = clk_prepare_enable(adc->clk);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "clk enable failed\n");
-		return ret;
+	if (adc->clk) {
+		ret = clk_prepare_enable(adc->clk);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "clk enable failed\n");
+			return ret;
+		}
 	}
 
 	ret = stm32_adc_of_get_resolution(indio_dev);
@@ -1070,6 +1681,12 @@ static int stm32_adc_probe(struct platform_device *pdev)
 		goto err_clk_disable;
 	stm32_adc_set_res(adc);
 
+	if (adc->cfg->selfcalib) {
+		ret = adc->cfg->selfcalib(adc);
+		if (ret)
+			goto err_clk_disable;
+	}
+
 	ret = stm32_adc_chan_of_init(indio_dev);
 	if (ret < 0)
 		goto err_clk_disable;
@@ -1106,7 +1723,8 @@ err_dma_disable:
 		dma_release_channel(adc->dma_chan);
 	}
 err_clk_disable:
-	clk_disable_unprepare(adc->clk);
+	if (adc->clk)
+		clk_disable_unprepare(adc->clk);
 
 	return ret;
 }
@@ -1124,13 +1742,35 @@ static int stm32_adc_remove(struct platform_device *pdev)
 				  adc->rx_buf, adc->rx_dma_buf);
 		dma_release_channel(adc->dma_chan);
 	}
-	clk_disable_unprepare(adc->clk);
+	if (adc->clk)
+		clk_disable_unprepare(adc->clk);
 
 	return 0;
 }
 
+static const struct stm32_adc_cfg stm32f4_adc_cfg = {
+	.regs = &stm32f4_adc_regspec,
+	.adc_info = &stm32f4_adc_info,
+	.trigs = stm32f4_adc_trigs,
+	.clk_required = true,
+	.start_conv = stm32f4_adc_start_conv,
+	.stop_conv = stm32f4_adc_stop_conv,
+};
+
+static const struct stm32_adc_cfg stm32h7_adc_cfg = {
+	.regs = &stm32h7_adc_regspec,
+	.adc_info = &stm32h7_adc_info,
+	.trigs = stm32h7_adc_trigs,
+	.selfcalib = stm32h7_adc_selfcalib,
+	.start_conv = stm32h7_adc_start_conv,
+	.stop_conv = stm32h7_adc_stop_conv,
+	.prepare = stm32h7_adc_prepare,
+	.unprepare = stm32h7_adc_unprepare,
+};
+
 static const struct of_device_id stm32_adc_of_match[] = {
-	{ .compatible = "st,stm32f4-adc" },
+	{ .compatible = "st,stm32f4-adc", .data = (void *)&stm32f4_adc_cfg },
+	{ .compatible = "st,stm32h7-adc", .data = (void *)&stm32h7_adc_cfg },
 	{},
 };
 MODULE_DEVICE_TABLE(of, stm32_adc_of_match);