Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1355 insertions, 0 deletions

diff --git a/drivers/iio/adc/meson_saradc.c b/drivers/iio/adc/meson_saradc.c
new file mode 100644
index 000000000..e771299fa
--- /dev/null
+++ b/drivers/iio/adc/meson_saradc.c
@@ -0,0 +1,1355 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Amlogic Meson Successive Approximation Register (SAR) A/D Converter
+ *
+ * Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/mfd/syscon.h>
+
+#define MESON_SAR_ADC_REG0					0x00
+	#define MESON_SAR_ADC_REG0_PANEL_DETECT			BIT(31)
+	#define MESON_SAR_ADC_REG0_BUSY_MASK			GENMASK(30, 28)
+	#define MESON_SAR_ADC_REG0_DELTA_BUSY			BIT(30)
+	#define MESON_SAR_ADC_REG0_AVG_BUSY			BIT(29)
+	#define MESON_SAR_ADC_REG0_SAMPLE_BUSY			BIT(28)
+	#define MESON_SAR_ADC_REG0_FIFO_FULL			BIT(27)
+	#define MESON_SAR_ADC_REG0_FIFO_EMPTY			BIT(26)
+	#define MESON_SAR_ADC_REG0_FIFO_COUNT_MASK		GENMASK(25, 21)
+	#define MESON_SAR_ADC_REG0_ADC_BIAS_CTRL_MASK		GENMASK(20, 19)
+	#define MESON_SAR_ADC_REG0_CURR_CHAN_ID_MASK		GENMASK(18, 16)
+	#define MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL		BIT(15)
+	#define MESON_SAR_ADC_REG0_SAMPLING_STOP		BIT(14)
+	#define MESON_SAR_ADC_REG0_CHAN_DELTA_EN_MASK		GENMASK(13, 12)
+	#define MESON_SAR_ADC_REG0_DETECT_IRQ_POL		BIT(10)
+	#define MESON_SAR_ADC_REG0_DETECT_IRQ_EN		BIT(9)
+	#define MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK		GENMASK(8, 4)
+	#define MESON_SAR_ADC_REG0_FIFO_IRQ_EN			BIT(3)
+	#define MESON_SAR_ADC_REG0_SAMPLING_START		BIT(2)
+	#define MESON_SAR_ADC_REG0_CONTINUOUS_EN		BIT(1)
+	#define MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE		BIT(0)
+
+#define MESON_SAR_ADC_CHAN_LIST					0x04
+	#define MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK		GENMASK(26, 24)
+	#define MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(_chan)	\
+					(GENMASK(2, 0) << ((_chan) * 3))
+
+#define MESON_SAR_ADC_AVG_CNTL					0x08
+	#define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(_chan)	\
+					(16 + ((_chan) * 2))
+	#define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(_chan)	\
+					(GENMASK(17, 16) << ((_chan) * 2))
+	#define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(_chan)	\
+					(0 + ((_chan) * 2))
+	#define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(_chan)	\
+					(GENMASK(1, 0) << ((_chan) * 2))
+
+#define MESON_SAR_ADC_REG3					0x0c
+	#define MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY		BIT(31)
+	#define MESON_SAR_ADC_REG3_CLK_EN			BIT(30)
+	#define MESON_SAR_ADC_REG3_BL30_INITIALIZED		BIT(28)
+	#define MESON_SAR_ADC_REG3_CTRL_CONT_RING_COUNTER_EN	BIT(27)
+	#define MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE	BIT(26)
+	#define MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK	GENMASK(25, 23)
+	#define MESON_SAR_ADC_REG3_DETECT_EN			BIT(22)
+	#define MESON_SAR_ADC_REG3_ADC_EN			BIT(21)
+	#define MESON_SAR_ADC_REG3_PANEL_DETECT_COUNT_MASK	GENMASK(20, 18)
+	#define MESON_SAR_ADC_REG3_PANEL_DETECT_FILTER_TB_MASK	GENMASK(17, 16)
+	#define MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT		10
+	#define MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH		6
+	#define MESON_SAR_ADC_REG3_BLOCK_DLY_SEL_MASK		GENMASK(9, 8)
+	#define MESON_SAR_ADC_REG3_BLOCK_DLY_MASK		GENMASK(7, 0)
+
+#define MESON_SAR_ADC_DELAY					0x10
+	#define MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK		GENMASK(25, 24)
+	#define MESON_SAR_ADC_DELAY_BL30_BUSY			BIT(15)
+	#define MESON_SAR_ADC_DELAY_KERNEL_BUSY			BIT(14)
+	#define MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK		GENMASK(23, 16)
+	#define MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK		GENMASK(9, 8)
+	#define MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK		GENMASK(7, 0)
+
+#define MESON_SAR_ADC_LAST_RD					0x14
+	#define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL1_MASK	GENMASK(23, 16)
+	#define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL0_MASK	GENMASK(9, 0)
+
+#define MESON_SAR_ADC_FIFO_RD					0x18
+	#define MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK		GENMASK(14, 12)
+	#define MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK		GENMASK(11, 0)
+
+#define MESON_SAR_ADC_AUX_SW					0x1c
+	#define MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(_chan)	\
+					(8 + (((_chan) - 2) * 3))
+	#define MESON_SAR_ADC_AUX_SW_VREF_P_MUX			BIT(6)
+	#define MESON_SAR_ADC_AUX_SW_VREF_N_MUX			BIT(5)
+	#define MESON_SAR_ADC_AUX_SW_MODE_SEL			BIT(4)
+	#define MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW		BIT(3)
+	#define MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW		BIT(2)
+	#define MESON_SAR_ADC_AUX_SW_YM_DRIVE_SW		BIT(1)
+	#define MESON_SAR_ADC_AUX_SW_XM_DRIVE_SW		BIT(0)
+
+#define MESON_SAR_ADC_CHAN_10_SW				0x20
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK	GENMASK(25, 23)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_P_MUX	BIT(22)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_N_MUX	BIT(21)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MODE_SEL		BIT(20)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YP_DRIVE_SW	BIT(19)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XP_DRIVE_SW	BIT(18)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YM_DRIVE_SW	BIT(17)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XM_DRIVE_SW	BIT(16)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK	GENMASK(9, 7)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_P_MUX	BIT(6)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_N_MUX	BIT(5)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MODE_SEL		BIT(4)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YP_DRIVE_SW	BIT(3)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XP_DRIVE_SW	BIT(2)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YM_DRIVE_SW	BIT(1)
+	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XM_DRIVE_SW	BIT(0)
+
+#define MESON_SAR_ADC_DETECT_IDLE_SW				0x24
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_SW_EN	BIT(26)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK	GENMASK(25, 23)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_P_MUX	BIT(22)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_N_MUX	BIT(21)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MODE_SEL	BIT(20)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YP_DRIVE_SW	BIT(19)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XP_DRIVE_SW	BIT(18)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YM_DRIVE_SW	BIT(17)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XM_DRIVE_SW	BIT(16)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK	GENMASK(9, 7)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_P_MUX	BIT(6)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_N_MUX	BIT(5)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MODE_SEL	BIT(4)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YP_DRIVE_SW	BIT(3)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XP_DRIVE_SW	BIT(2)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YM_DRIVE_SW	BIT(1)
+	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XM_DRIVE_SW	BIT(0)
+
+#define MESON_SAR_ADC_DELTA_10					0x28
+	#define MESON_SAR_ADC_DELTA_10_TEMP_SEL			BIT(27)
+	#define MESON_SAR_ADC_DELTA_10_TS_REVE1			BIT(26)
+	#define MESON_SAR_ADC_DELTA_10_CHAN1_DELTA_VALUE_MASK	GENMASK(25, 16)
+	#define MESON_SAR_ADC_DELTA_10_TS_REVE0			BIT(15)
+	#define MESON_SAR_ADC_DELTA_10_TS_C_MASK		GENMASK(14, 11)
+	#define MESON_SAR_ADC_DELTA_10_TS_VBG_EN		BIT(10)
+	#define MESON_SAR_ADC_DELTA_10_CHAN0_DELTA_VALUE_MASK	GENMASK(9, 0)
+
+/*
+ * NOTE: registers from here are undocumented (the vendor Linux kernel driver
+ * and u-boot source served as reference). These only seem to be relevant on
+ * GXBB and newer.
+ */
+#define MESON_SAR_ADC_REG11					0x2c
+	#define MESON_SAR_ADC_REG11_BANDGAP_EN			BIT(13)
+
+#define MESON_SAR_ADC_REG13					0x34
+	#define MESON_SAR_ADC_REG13_12BIT_CALIBRATION_MASK	GENMASK(13, 8)
+
+#define MESON_SAR_ADC_MAX_FIFO_SIZE				32
+#define MESON_SAR_ADC_TIMEOUT					100 /* ms */
+#define MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL			6
+#define MESON_SAR_ADC_TEMP_OFFSET				27
+
+/* temperature sensor calibration information in eFuse */
+#define MESON_SAR_ADC_EFUSE_BYTES				4
+#define MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL			GENMASK(6, 0)
+#define MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED			BIT(7)
+
+#define MESON_HHI_DPLL_TOP_0					0x318
+#define MESON_HHI_DPLL_TOP_0_TSC_BIT4				BIT(9)
+
+/* for use with IIO_VAL_INT_PLUS_MICRO */
+#define MILLION							1000000
+
+#define MESON_SAR_ADC_CHAN(_chan) {					\
+	.type = IIO_VOLTAGE,						\
+	.indexed = 1,							\
+	.channel = _chan,						\
+	.address = _chan,						\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
+				BIT(IIO_CHAN_INFO_AVERAGE_RAW),		\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
+	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) |	\
+				BIT(IIO_CHAN_INFO_CALIBSCALE),		\
+	.datasheet_name = "SAR_ADC_CH"#_chan,				\
+}
+
+#define MESON_SAR_ADC_TEMP_CHAN(_chan) {				\
+	.type = IIO_TEMP,						\
+	.channel = _chan,						\
+	.address = MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL,		\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
+				BIT(IIO_CHAN_INFO_AVERAGE_RAW),		\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |		\
+					BIT(IIO_CHAN_INFO_SCALE),	\
+	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) |	\
+				BIT(IIO_CHAN_INFO_CALIBSCALE),		\
+	.datasheet_name = "TEMP_SENSOR",				\
+}
+
+static const struct iio_chan_spec meson_sar_adc_iio_channels[] = {
+	MESON_SAR_ADC_CHAN(0),
+	MESON_SAR_ADC_CHAN(1),
+	MESON_SAR_ADC_CHAN(2),
+	MESON_SAR_ADC_CHAN(3),
+	MESON_SAR_ADC_CHAN(4),
+	MESON_SAR_ADC_CHAN(5),
+	MESON_SAR_ADC_CHAN(6),
+	MESON_SAR_ADC_CHAN(7),
+	IIO_CHAN_SOFT_TIMESTAMP(8),
+};
+
+static const struct iio_chan_spec meson_sar_adc_and_temp_iio_channels[] = {
+	MESON_SAR_ADC_CHAN(0),
+	MESON_SAR_ADC_CHAN(1),
+	MESON_SAR_ADC_CHAN(2),
+	MESON_SAR_ADC_CHAN(3),
+	MESON_SAR_ADC_CHAN(4),
+	MESON_SAR_ADC_CHAN(5),
+	MESON_SAR_ADC_CHAN(6),
+	MESON_SAR_ADC_CHAN(7),
+	MESON_SAR_ADC_TEMP_CHAN(8),
+	IIO_CHAN_SOFT_TIMESTAMP(9),
+};
+
+enum meson_sar_adc_avg_mode {
+	NO_AVERAGING = 0x0,
+	MEAN_AVERAGING = 0x1,
+	MEDIAN_AVERAGING = 0x2,
+};
+
+enum meson_sar_adc_num_samples {
+	ONE_SAMPLE = 0x0,
+	TWO_SAMPLES = 0x1,
+	FOUR_SAMPLES = 0x2,
+	EIGHT_SAMPLES = 0x3,
+};
+
+enum meson_sar_adc_chan7_mux_sel {
+	CHAN7_MUX_VSS = 0x0,
+	CHAN7_MUX_VDD_DIV4 = 0x1,
+	CHAN7_MUX_VDD_DIV2 = 0x2,
+	CHAN7_MUX_VDD_MUL3_DIV4 = 0x3,
+	CHAN7_MUX_VDD = 0x4,
+	CHAN7_MUX_CH7_INPUT = 0x7,
+};
+
+struct meson_sar_adc_param {
+	bool					has_bl30_integration;
+	unsigned long				clock_rate;
+	u32					bandgap_reg;
+	unsigned int				resolution;
+	const struct regmap_config		*regmap_config;
+	u8					temperature_trimming_bits;
+	unsigned int				temperature_multiplier;
+	unsigned int				temperature_divider;
+};
+
+struct meson_sar_adc_data {
+	const struct meson_sar_adc_param	*param;
+	const char				*name;
+};
+
+struct meson_sar_adc_priv {
+	struct regmap				*regmap;
+	struct regulator			*vref;
+	const struct meson_sar_adc_param	*param;
+	struct clk				*clkin;
+	struct clk				*core_clk;
+	struct clk				*adc_sel_clk;
+	struct clk				*adc_clk;
+	struct clk_gate				clk_gate;
+	struct clk				*adc_div_clk;
+	struct clk_divider			clk_div;
+	struct completion			done;
+	int					calibbias;
+	int					calibscale;
+	struct regmap				*tsc_regmap;
+	bool					temperature_sensor_calibrated;
+	u8					temperature_sensor_coefficient;
+	u16					temperature_sensor_adc_val;
+};
+
+static const struct regmap_config meson_sar_adc_regmap_config_gxbb = {
+	.reg_bits = 8,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = MESON_SAR_ADC_REG13,
+};
+
+static const struct regmap_config meson_sar_adc_regmap_config_meson8 = {
+	.reg_bits = 8,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = MESON_SAR_ADC_DELTA_10,
+};
+
+static unsigned int meson_sar_adc_get_fifo_count(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	u32 regval;
+
+	regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
+
+	return FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
+}
+
+static int meson_sar_adc_calib_val(struct iio_dev *indio_dev, int val)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	int tmp;
+
+	/* use val_calib = scale * val_raw + offset calibration function */
+	tmp = div_s64((s64)val * priv->calibscale, MILLION) + priv->calibbias;
+
+	return clamp(tmp, 0, (1 << priv->param->resolution) - 1);
+}
+
+static int meson_sar_adc_wait_busy_clear(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	int regval, timeout = 10000;
+
+	/*
+	 * NOTE: we need a small delay before reading the status, otherwise
+	 * the sample engine may not have started internally (which would
+	 * seem to us that sampling is already finished).
+	 */
+	do {
+		udelay(1);
+		regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
+	} while (FIELD_GET(MESON_SAR_ADC_REG0_BUSY_MASK, regval) && timeout--);
+
+	if (timeout < 0)
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+static int meson_sar_adc_read_raw_sample(struct iio_dev *indio_dev,
+					 const struct iio_chan_spec *chan,
+					 int *val)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	int regval, fifo_chan, fifo_val, count;
+
+	if(!wait_for_completion_timeout(&priv->done,
+				msecs_to_jiffies(MESON_SAR_ADC_TIMEOUT)))
+		return -ETIMEDOUT;
+
+	count = meson_sar_adc_get_fifo_count(indio_dev);
+	if (count != 1) {
+		dev_err(&indio_dev->dev,
+			"ADC FIFO has %d element(s) instead of one\n", count);
+		return -EINVAL;
+	}
+
+	regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &regval);
+	fifo_chan = FIELD_GET(MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK, regval);
+	if (fifo_chan != chan->address) {
+		dev_err(&indio_dev->dev,
+			"ADC FIFO entry belongs to channel %d instead of %lu\n",
+			fifo_chan, chan->address);
+		return -EINVAL;
+	}
+
+	fifo_val = FIELD_GET(MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK, regval);
+	fifo_val &= GENMASK(priv->param->resolution - 1, 0);
+	*val = meson_sar_adc_calib_val(indio_dev, fifo_val);
+
+	return 0;
+}
+
+static void meson_sar_adc_set_averaging(struct iio_dev *indio_dev,
+					const struct iio_chan_spec *chan,
+					enum meson_sar_adc_avg_mode mode,
+					enum meson_sar_adc_num_samples samples)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	int val, address = chan->address;
+
+	val = samples << MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(address);
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
+			   MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(address),
+			   val);
+
+	val = mode << MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(address);
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
+			   MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(address), val);
+}
+
+static void meson_sar_adc_enable_channel(struct iio_dev *indio_dev,
+					const struct iio_chan_spec *chan)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	u32 regval;
+
+	/*
+	 * the SAR ADC engine allows sampling multiple channels at the same
+	 * time. to keep it simple we're only working with one *internal*
+	 * channel, which starts counting at index 0 (which means: count = 1).
+	 */
+	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, 0);
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
+			   MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, regval);
+
+	/* map channel index 0 to the channel which we want to read */
+	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0),
+			    chan->address);
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
+			   MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), regval);
+
+	regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
+			    chan->address);
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
+			   MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
+			   regval);
+
+	regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
+			    chan->address);
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
+			   MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
+			   regval);
+
+	if (chan->address == MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL) {
+		if (chan->type == IIO_TEMP)
+			regval = MESON_SAR_ADC_DELTA_10_TEMP_SEL;
+		else
+			regval = 0;
+
+		regmap_update_bits(priv->regmap,
+				   MESON_SAR_ADC_DELTA_10,
+				   MESON_SAR_ADC_DELTA_10_TEMP_SEL, regval);
+	}
+}
+
+static void meson_sar_adc_set_chan7_mux(struct iio_dev *indio_dev,
+					enum meson_sar_adc_chan7_mux_sel sel)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	u32 regval;
+
+	regval = FIELD_PREP(MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, sel);
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+			   MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, regval);
+
+	usleep_range(10, 20);
+}
+
+static void meson_sar_adc_start_sample_engine(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+
+	reinit_completion(&priv->done);
+
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+			   MESON_SAR_ADC_REG0_FIFO_IRQ_EN,
+			   MESON_SAR_ADC_REG0_FIFO_IRQ_EN);
+
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+			   MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE,
+			   MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE);
+
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+			   MESON_SAR_ADC_REG0_SAMPLING_START,
+			   MESON_SAR_ADC_REG0_SAMPLING_START);
+}
+
+static void meson_sar_adc_stop_sample_engine(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+			   MESON_SAR_ADC_REG0_FIFO_IRQ_EN, 0);
+
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+			   MESON_SAR_ADC_REG0_SAMPLING_STOP,
+			   MESON_SAR_ADC_REG0_SAMPLING_STOP);
+
+	/* wait until all modules are stopped */
+	meson_sar_adc_wait_busy_clear(indio_dev);
+
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+			   MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE, 0);
+}
+
+static int meson_sar_adc_lock(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	int val, timeout = 10000;
+
+	mutex_lock(&indio_dev->mlock);
+
+	if (priv->param->has_bl30_integration) {
+		/* prevent BL30 from using the SAR ADC while we are using it */
+		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+				MESON_SAR_ADC_DELAY_KERNEL_BUSY,
+				MESON_SAR_ADC_DELAY_KERNEL_BUSY);
+
+		/*
+		 * wait until BL30 releases it's lock (so we can use the SAR
+		 * ADC)
+		 */
+		do {
+			udelay(1);
+			regmap_read(priv->regmap, MESON_SAR_ADC_DELAY, &val);
+		} while (val & MESON_SAR_ADC_DELAY_BL30_BUSY && timeout--);
+
+		if (timeout < 0) {
+			mutex_unlock(&indio_dev->mlock);
+			return -ETIMEDOUT;
+		}
+	}
+
+	return 0;
+}
+
+static void meson_sar_adc_unlock(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+
+	if (priv->param->has_bl30_integration)
+		/* allow BL30 to use the SAR ADC again */
+		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+				MESON_SAR_ADC_DELAY_KERNEL_BUSY, 0);
+
+	mutex_unlock(&indio_dev->mlock);
+}
+
+static void meson_sar_adc_clear_fifo(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	unsigned int count, tmp;
+
+	for (count = 0; count < MESON_SAR_ADC_MAX_FIFO_SIZE; count++) {
+		if (!meson_sar_adc_get_fifo_count(indio_dev))
+			break;
+
+		regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &tmp);
+	}
+}
+
+static int meson_sar_adc_get_sample(struct iio_dev *indio_dev,
+				    const struct iio_chan_spec *chan,
+				    enum meson_sar_adc_avg_mode avg_mode,
+				    enum meson_sar_adc_num_samples avg_samples,
+				    int *val)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	int ret;
+
+	if (chan->type == IIO_TEMP && !priv->temperature_sensor_calibrated)
+		return -ENOTSUPP;
+
+	ret = meson_sar_adc_lock(indio_dev);
+	if (ret)
+		return ret;
+
+	/* clear the FIFO to make sure we're not reading old values */
+	meson_sar_adc_clear_fifo(indio_dev);
+
+	meson_sar_adc_set_averaging(indio_dev, chan, avg_mode, avg_samples);
+
+	meson_sar_adc_enable_channel(indio_dev, chan);
+
+	meson_sar_adc_start_sample_engine(indio_dev);
+	ret = meson_sar_adc_read_raw_sample(indio_dev, chan, val);
+	meson_sar_adc_stop_sample_engine(indio_dev);
+
+	meson_sar_adc_unlock(indio_dev);
+
+	if (ret) {
+		dev_warn(indio_dev->dev.parent,
+			 "failed to read sample for channel %lu: %d\n",
+			 chan->address, ret);
+		return ret;
+	}
+
+	return IIO_VAL_INT;
+}
+
+static int meson_sar_adc_iio_info_read_raw(struct iio_dev *indio_dev,
+					   const struct iio_chan_spec *chan,
+					   int *val, int *val2, long mask)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		return meson_sar_adc_get_sample(indio_dev, chan, NO_AVERAGING,
+						ONE_SAMPLE, val);
+		break;
+
+	case IIO_CHAN_INFO_AVERAGE_RAW:
+		return meson_sar_adc_get_sample(indio_dev, chan,
+						MEAN_AVERAGING, EIGHT_SAMPLES,
+						val);
+		break;
+
+	case IIO_CHAN_INFO_SCALE:
+		if (chan->type == IIO_VOLTAGE) {
+			ret = regulator_get_voltage(priv->vref);
+			if (ret < 0) {
+				dev_err(indio_dev->dev.parent,
+					"failed to get vref voltage: %d\n",
+					ret);
+				return ret;
+			}
+
+			*val = ret / 1000;
+			*val2 = priv->param->resolution;
+			return IIO_VAL_FRACTIONAL_LOG2;
+		} else if (chan->type == IIO_TEMP) {
+			/* SoC specific multiplier and divider */
+			*val = priv->param->temperature_multiplier;
+			*val2 = priv->param->temperature_divider;
+
+			/* celsius to millicelsius */
+			*val *= 1000;
+
+			return IIO_VAL_FRACTIONAL;
+		} else {
+			return -EINVAL;
+		}
+
+	case IIO_CHAN_INFO_CALIBBIAS:
+		*val = priv->calibbias;
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_CALIBSCALE:
+		*val = priv->calibscale / MILLION;
+		*val2 = priv->calibscale % MILLION;
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	case IIO_CHAN_INFO_OFFSET:
+		*val = DIV_ROUND_CLOSEST(MESON_SAR_ADC_TEMP_OFFSET *
+					 priv->param->temperature_divider,
+					 priv->param->temperature_multiplier);
+		*val -= priv->temperature_sensor_adc_val;
+		return IIO_VAL_INT;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int meson_sar_adc_clk_init(struct iio_dev *indio_dev,
+				  void __iomem *base)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	struct clk_init_data init;
+	const char *clk_parents[1];
+
+	init.name = devm_kasprintf(&indio_dev->dev, GFP_KERNEL, "%s#adc_div",
+				   dev_name(indio_dev->dev.parent));
+	if (!init.name)
+		return -ENOMEM;
+
+	init.flags = 0;
+	init.ops = &clk_divider_ops;
+	clk_parents[0] = __clk_get_name(priv->clkin);
+	init.parent_names = clk_parents;
+	init.num_parents = 1;
+
+	priv->clk_div.reg = base + MESON_SAR_ADC_REG3;
+	priv->clk_div.shift = MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT;
+	priv->clk_div.width = MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH;
+	priv->clk_div.hw.init = &init;
+	priv->clk_div.flags = 0;
+
+	priv->adc_div_clk = devm_clk_register(&indio_dev->dev,
+					      &priv->clk_div.hw);
+	if (WARN_ON(IS_ERR(priv->adc_div_clk)))
+		return PTR_ERR(priv->adc_div_clk);
+
+	init.name = devm_kasprintf(&indio_dev->dev, GFP_KERNEL, "%s#adc_en",
+				   dev_name(indio_dev->dev.parent));
+	if (!init.name)
+		return -ENOMEM;
+
+	init.flags = CLK_SET_RATE_PARENT;
+	init.ops = &clk_gate_ops;
+	clk_parents[0] = __clk_get_name(priv->adc_div_clk);
+	init.parent_names = clk_parents;
+	init.num_parents = 1;
+
+	priv->clk_gate.reg = base + MESON_SAR_ADC_REG3;
+	priv->clk_gate.bit_idx = __ffs(MESON_SAR_ADC_REG3_CLK_EN);
+	priv->clk_gate.hw.init = &init;
+
+	priv->adc_clk = devm_clk_register(&indio_dev->dev, &priv->clk_gate.hw);
+	if (WARN_ON(IS_ERR(priv->adc_clk)))
+		return PTR_ERR(priv->adc_clk);
+
+	return 0;
+}
+
+static int meson_sar_adc_temp_sensor_init(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	u8 *buf, trimming_bits, trimming_mask, upper_adc_val;
+	struct nvmem_cell *temperature_calib;
+	size_t read_len;
+	int ret;
+
+	temperature_calib = devm_nvmem_cell_get(indio_dev->dev.parent,
+						"temperature_calib");
+	if (IS_ERR(temperature_calib)) {
+		ret = PTR_ERR(temperature_calib);
+
+		/*
+		 * leave the temperature sensor disabled if no calibration data
+		 * was passed via nvmem-cells.
+		 */
+		if (ret == -ENODEV)
+			return 0;
+
+		return dev_err_probe(indio_dev->dev.parent, ret,
+				     "failed to get temperature_calib cell\n");
+	}
+
+	priv->tsc_regmap =
+		syscon_regmap_lookup_by_phandle(indio_dev->dev.parent->of_node,
+						"amlogic,hhi-sysctrl");
+	if (IS_ERR(priv->tsc_regmap)) {
+		dev_err(indio_dev->dev.parent,
+			"failed to get amlogic,hhi-sysctrl regmap\n");
+		return PTR_ERR(priv->tsc_regmap);
+	}
+
+	read_len = MESON_SAR_ADC_EFUSE_BYTES;
+	buf = nvmem_cell_read(temperature_calib, &read_len);
+	if (IS_ERR(buf)) {
+		dev_err(indio_dev->dev.parent,
+			"failed to read temperature_calib cell\n");
+		return PTR_ERR(buf);
+	} else if (read_len != MESON_SAR_ADC_EFUSE_BYTES) {
+		kfree(buf);
+		dev_err(indio_dev->dev.parent,
+			"invalid read size of temperature_calib cell\n");
+		return -EINVAL;
+	}
+
+	trimming_bits = priv->param->temperature_trimming_bits;
+	trimming_mask = BIT(trimming_bits) - 1;
+
+	priv->temperature_sensor_calibrated =
+		buf[3] & MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED;
+	priv->temperature_sensor_coefficient = buf[2] & trimming_mask;
+
+	upper_adc_val = FIELD_GET(MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL,
+				  buf[3]);
+
+	priv->temperature_sensor_adc_val = buf[2];
+	priv->temperature_sensor_adc_val |= upper_adc_val << BITS_PER_BYTE;
+	priv->temperature_sensor_adc_val >>= trimming_bits;
+
+	kfree(buf);
+
+	return 0;
+}
+
+static int meson_sar_adc_init(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	int regval, i, ret;
+
+	/*
+	 * make sure we start at CH7 input since the other muxes are only used
+	 * for internal calibration.
+	 */
+	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
+
+	if (priv->param->has_bl30_integration) {
+		/*
+		 * leave sampling delay and the input clocks as configured by
+		 * BL30 to make sure BL30 gets the values it expects when
+		 * reading the temperature sensor.
+		 */
+		regmap_read(priv->regmap, MESON_SAR_ADC_REG3, &regval);
+		if (regval & MESON_SAR_ADC_REG3_BL30_INITIALIZED)
+			return 0;
+	}
+
+	meson_sar_adc_stop_sample_engine(indio_dev);
+
+	/*
+	 * disable this bit as seems to be only relevant for Meson6 (based
+	 * on the vendor driver), which we don't support at the moment.
+	 */
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+			MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL, 0);
+
+	/* disable all channels by default */
+	regmap_write(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 0x0);
+
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+			   MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE, 0);
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+			   MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY,
+			   MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY);
+
+	/* delay between two samples = (10+1) * 1uS */
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+			   MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
+			   FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK,
+				      10));
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+			   MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
+			   FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
+				      0));
+
+	/* delay between two samples = (10+1) * 1uS */
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+			   MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
+			   FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
+				      10));
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+			   MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
+			   FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
+				      1));
+
+	/*
+	 * set up the input channel muxes in MESON_SAR_ADC_CHAN_10_SW
+	 * (0 = SAR_ADC_CH0, 1 = SAR_ADC_CH1)
+	 */
+	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK, 0);
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
+			   MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK,
+			   regval);
+	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK, 1);
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
+			   MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK,
+			   regval);
+
+	/*
+	 * set up the input channel muxes in MESON_SAR_ADC_AUX_SW
+	 * (2 = SAR_ADC_CH2, 3 = SAR_ADC_CH3, ...) and enable
+	 * MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW and
+	 * MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW like the vendor driver.
+	 */
+	regval = 0;
+	for (i = 2; i <= 7; i++)
+		regval |= i << MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(i);
+	regval |= MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW;
+	regval |= MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW;
+	regmap_write(priv->regmap, MESON_SAR_ADC_AUX_SW, regval);
+
+	if (priv->temperature_sensor_calibrated) {
+		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
+				   MESON_SAR_ADC_DELTA_10_TS_REVE1,
+				   MESON_SAR_ADC_DELTA_10_TS_REVE1);
+		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
+				   MESON_SAR_ADC_DELTA_10_TS_REVE0,
+				   MESON_SAR_ADC_DELTA_10_TS_REVE0);
+
+		/*
+		 * set bits [3:0] of the TSC (temperature sensor coefficient)
+		 * to get the correct values when reading the temperature.
+		 */
+		regval = FIELD_PREP(MESON_SAR_ADC_DELTA_10_TS_C_MASK,
+				    priv->temperature_sensor_coefficient);
+		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
+				   MESON_SAR_ADC_DELTA_10_TS_C_MASK, regval);
+
+		if (priv->param->temperature_trimming_bits == 5) {
+			if (priv->temperature_sensor_coefficient & BIT(4))
+				regval = MESON_HHI_DPLL_TOP_0_TSC_BIT4;
+			else
+				regval = 0;
+
+			/*
+			 * bit [4] (the 5th bit when starting to count at 1)
+			 * of the TSC is located in the HHI register area.
+			 */
+			regmap_update_bits(priv->tsc_regmap,
+					   MESON_HHI_DPLL_TOP_0,
+					   MESON_HHI_DPLL_TOP_0_TSC_BIT4,
+					   regval);
+		}
+	} else {
+		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
+				   MESON_SAR_ADC_DELTA_10_TS_REVE1, 0);
+		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
+				   MESON_SAR_ADC_DELTA_10_TS_REVE0, 0);
+	}
+
+	ret = clk_set_parent(priv->adc_sel_clk, priv->clkin);
+	if (ret) {
+		dev_err(indio_dev->dev.parent,
+			"failed to set adc parent to clkin\n");
+		return ret;
+	}
+
+	ret = clk_set_rate(priv->adc_clk, priv->param->clock_rate);
+	if (ret) {
+		dev_err(indio_dev->dev.parent,
+			"failed to set adc clock rate\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static void meson_sar_adc_set_bandgap(struct iio_dev *indio_dev, bool on_off)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	const struct meson_sar_adc_param *param = priv->param;
+	u32 enable_mask;
+
+	if (param->bandgap_reg == MESON_SAR_ADC_REG11)
+		enable_mask = MESON_SAR_ADC_REG11_BANDGAP_EN;
+	else
+		enable_mask = MESON_SAR_ADC_DELTA_10_TS_VBG_EN;
+
+	regmap_update_bits(priv->regmap, param->bandgap_reg, enable_mask,
+			   on_off ? enable_mask : 0);
+}
+
+static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	int ret;
+	u32 regval;
+
+	ret = meson_sar_adc_lock(indio_dev);
+	if (ret)
+		goto err_lock;
+
+	ret = regulator_enable(priv->vref);
+	if (ret < 0) {
+		dev_err(indio_dev->dev.parent,
+			"failed to enable vref regulator\n");
+		goto err_vref;
+	}
+
+	ret = clk_prepare_enable(priv->core_clk);
+	if (ret) {
+		dev_err(indio_dev->dev.parent, "failed to enable core clk\n");
+		goto err_core_clk;
+	}
+
+	regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1);
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+			   MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
+
+	meson_sar_adc_set_bandgap(indio_dev, true);
+
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+			   MESON_SAR_ADC_REG3_ADC_EN,
+			   MESON_SAR_ADC_REG3_ADC_EN);
+
+	udelay(5);
+
+	ret = clk_prepare_enable(priv->adc_clk);
+	if (ret) {
+		dev_err(indio_dev->dev.parent, "failed to enable adc clk\n");
+		goto err_adc_clk;
+	}
+
+	meson_sar_adc_unlock(indio_dev);
+
+	return 0;
+
+err_adc_clk:
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+			   MESON_SAR_ADC_REG3_ADC_EN, 0);
+	meson_sar_adc_set_bandgap(indio_dev, false);
+	clk_disable_unprepare(priv->core_clk);
+err_core_clk:
+	regulator_disable(priv->vref);
+err_vref:
+	meson_sar_adc_unlock(indio_dev);
+err_lock:
+	return ret;
+}
+
+static int meson_sar_adc_hw_disable(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	int ret;
+
+	ret = meson_sar_adc_lock(indio_dev);
+	if (ret)
+		return ret;
+
+	clk_disable_unprepare(priv->adc_clk);
+
+	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+			   MESON_SAR_ADC_REG3_ADC_EN, 0);
+
+	meson_sar_adc_set_bandgap(indio_dev, false);
+
+	clk_disable_unprepare(priv->core_clk);
+
+	regulator_disable(priv->vref);
+
+	meson_sar_adc_unlock(indio_dev);
+
+	return 0;
+}
+
+static irqreturn_t meson_sar_adc_irq(int irq, void *data)
+{
+	struct iio_dev *indio_dev = data;
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	unsigned int cnt, threshold;
+	u32 regval;
+
+	regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
+	cnt = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
+	threshold = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
+
+	if (cnt < threshold)
+		return IRQ_NONE;
+
+	complete(&priv->done);
+
+	return IRQ_HANDLED;
+}
+
+static int meson_sar_adc_calib(struct iio_dev *indio_dev)
+{
+	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+	int ret, nominal0, nominal1, value0, value1;
+
+	/* use points 25% and 75% for calibration */
+	nominal0 = (1 << priv->param->resolution) / 4;
+	nominal1 = (1 << priv->param->resolution) * 3 / 4;
+
+	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_DIV4);
+	usleep_range(10, 20);
+	ret = meson_sar_adc_get_sample(indio_dev,
+				       &indio_dev->channels[7],
+				       MEAN_AVERAGING, EIGHT_SAMPLES, &value0);
+	if (ret < 0)
+		goto out;
+
+	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_MUL3_DIV4);
+	usleep_range(10, 20);
+	ret = meson_sar_adc_get_sample(indio_dev,
+				       &indio_dev->channels[7],
+				       MEAN_AVERAGING, EIGHT_SAMPLES, &value1);
+	if (ret < 0)
+		goto out;
+
+	if (value1 <= value0) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	priv->calibscale = div_s64((nominal1 - nominal0) * (s64)MILLION,
+				   value1 - value0);
+	priv->calibbias = nominal0 - div_s64((s64)value0 * priv->calibscale,
+					     MILLION);
+	ret = 0;
+out:
+	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
+
+	return ret;
+}
+
+static const struct iio_info meson_sar_adc_iio_info = {
+	.read_raw = meson_sar_adc_iio_info_read_raw,
+};
+
+static const struct meson_sar_adc_param meson_sar_adc_meson8_param = {
+	.has_bl30_integration = false,
+	.clock_rate = 1150000,
+	.bandgap_reg = MESON_SAR_ADC_DELTA_10,
+	.regmap_config = &meson_sar_adc_regmap_config_meson8,
+	.resolution = 10,
+	.temperature_trimming_bits = 4,
+	.temperature_multiplier = 18 * 10000,
+	.temperature_divider = 1024 * 10 * 85,
+};
+
+static const struct meson_sar_adc_param meson_sar_adc_meson8b_param = {
+	.has_bl30_integration = false,
+	.clock_rate = 1150000,
+	.bandgap_reg = MESON_SAR_ADC_DELTA_10,
+	.regmap_config = &meson_sar_adc_regmap_config_meson8,
+	.resolution = 10,
+	.temperature_trimming_bits = 5,
+	.temperature_multiplier = 10,
+	.temperature_divider = 32,
+};
+
+static const struct meson_sar_adc_param meson_sar_adc_gxbb_param = {
+	.has_bl30_integration = true,
+	.clock_rate = 1200000,
+	.bandgap_reg = MESON_SAR_ADC_REG11,
+	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
+	.resolution = 10,
+};
+
+static const struct meson_sar_adc_param meson_sar_adc_gxl_param = {
+	.has_bl30_integration = true,
+	.clock_rate = 1200000,
+	.bandgap_reg = MESON_SAR_ADC_REG11,
+	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
+	.resolution = 12,
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_meson8_data = {
+	.param = &meson_sar_adc_meson8_param,
+	.name = "meson-meson8-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_meson8b_data = {
+	.param = &meson_sar_adc_meson8b_param,
+	.name = "meson-meson8b-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_meson8m2_data = {
+	.param = &meson_sar_adc_meson8b_param,
+	.name = "meson-meson8m2-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_gxbb_data = {
+	.param = &meson_sar_adc_gxbb_param,
+	.name = "meson-gxbb-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_gxl_data = {
+	.param = &meson_sar_adc_gxl_param,
+	.name = "meson-gxl-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_gxm_data = {
+	.param = &meson_sar_adc_gxl_param,
+	.name = "meson-gxm-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_axg_data = {
+	.param = &meson_sar_adc_gxl_param,
+	.name = "meson-axg-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_g12a_data = {
+	.param = &meson_sar_adc_gxl_param,
+	.name = "meson-g12a-saradc",
+};
+
+static const struct of_device_id meson_sar_adc_of_match[] = {
+	{
+		.compatible = "amlogic,meson8-saradc",
+		.data = &meson_sar_adc_meson8_data,
+	}, {
+		.compatible = "amlogic,meson8b-saradc",
+		.data = &meson_sar_adc_meson8b_data,
+	}, {
+		.compatible = "amlogic,meson8m2-saradc",
+		.data = &meson_sar_adc_meson8m2_data,
+	}, {
+		.compatible = "amlogic,meson-gxbb-saradc",
+		.data = &meson_sar_adc_gxbb_data,
+	}, {
+		.compatible = "amlogic,meson-gxl-saradc",
+		.data = &meson_sar_adc_gxl_data,
+	}, {
+		.compatible = "amlogic,meson-gxm-saradc",
+		.data = &meson_sar_adc_gxm_data,
+	}, {
+		.compatible = "amlogic,meson-axg-saradc",
+		.data = &meson_sar_adc_axg_data,
+	}, {
+		.compatible = "amlogic,meson-g12a-saradc",
+		.data = &meson_sar_adc_g12a_data,
+	},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, meson_sar_adc_of_match);
+
+static int meson_sar_adc_probe(struct platform_device *pdev)
+{
+	const struct meson_sar_adc_data *match_data;
+	struct meson_sar_adc_priv *priv;
+	struct iio_dev *indio_dev;
+	void __iomem *base;
+	int irq, ret;
+
+	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv));
+	if (!indio_dev) {
+		dev_err(&pdev->dev, "failed allocating iio device\n");
+		return -ENOMEM;
+	}
+
+	priv = iio_priv(indio_dev);
+	init_completion(&priv->done);
+
+	match_data = of_device_get_match_data(&pdev->dev);
+	if (!match_data) {
+		dev_err(&pdev->dev, "failed to get match data\n");
+		return -ENODEV;
+	}
+
+	priv->param = match_data->param;
+
+	indio_dev->name = match_data->name;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &meson_sar_adc_iio_info;
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	priv->regmap = devm_regmap_init_mmio(&pdev->dev, base,
+					     priv->param->regmap_config);
+	if (IS_ERR(priv->regmap))
+		return PTR_ERR(priv->regmap);
+
+	irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
+	if (!irq)
+		return -EINVAL;
+
+	ret = devm_request_irq(&pdev->dev, irq, meson_sar_adc_irq, IRQF_SHARED,
+			       dev_name(&pdev->dev), indio_dev);
+	if (ret)
+		return ret;
+
+	priv->clkin = devm_clk_get(&pdev->dev, "clkin");
+	if (IS_ERR(priv->clkin)) {
+		dev_err(&pdev->dev, "failed to get clkin\n");
+		return PTR_ERR(priv->clkin);
+	}
+
+	priv->core_clk = devm_clk_get(&pdev->dev, "core");
+	if (IS_ERR(priv->core_clk)) {
+		dev_err(&pdev->dev, "failed to get core clk\n");
+		return PTR_ERR(priv->core_clk);
+	}
+
+	priv->adc_clk = devm_clk_get(&pdev->dev, "adc_clk");
+	if (IS_ERR(priv->adc_clk)) {
+		if (PTR_ERR(priv->adc_clk) == -ENOENT) {
+			priv->adc_clk = NULL;
+		} else {
+			dev_err(&pdev->dev, "failed to get adc clk\n");
+			return PTR_ERR(priv->adc_clk);
+		}
+	}
+
+	priv->adc_sel_clk = devm_clk_get(&pdev->dev, "adc_sel");
+	if (IS_ERR(priv->adc_sel_clk)) {
+		if (PTR_ERR(priv->adc_sel_clk) == -ENOENT) {
+			priv->adc_sel_clk = NULL;
+		} else {
+			dev_err(&pdev->dev, "failed to get adc_sel clk\n");
+			return PTR_ERR(priv->adc_sel_clk);
+		}
+	}
+
+	/* on pre-GXBB SoCs the SAR ADC itself provides the ADC clock: */
+	if (!priv->adc_clk) {
+		ret = meson_sar_adc_clk_init(indio_dev, base);
+		if (ret)
+			return ret;
+	}
+
+	priv->vref = devm_regulator_get(&pdev->dev, "vref");
+	if (IS_ERR(priv->vref)) {
+		dev_err(&pdev->dev, "failed to get vref regulator\n");
+		return PTR_ERR(priv->vref);
+	}
+
+	priv->calibscale = MILLION;
+
+	if (priv->param->temperature_trimming_bits) {
+		ret = meson_sar_adc_temp_sensor_init(indio_dev);
+		if (ret)
+			return ret;
+	}
+
+	if (priv->temperature_sensor_calibrated) {
+		indio_dev->channels = meson_sar_adc_and_temp_iio_channels;
+		indio_dev->num_channels =
+			ARRAY_SIZE(meson_sar_adc_and_temp_iio_channels);
+	} else {
+		indio_dev->channels = meson_sar_adc_iio_channels;
+		indio_dev->num_channels =
+			ARRAY_SIZE(meson_sar_adc_iio_channels);
+	}
+
+	ret = meson_sar_adc_init(indio_dev);
+	if (ret)
+		goto err;
+
+	ret = meson_sar_adc_hw_enable(indio_dev);
+	if (ret)
+		goto err;
+
+	ret = meson_sar_adc_calib(indio_dev);
+	if (ret)
+		dev_warn(&pdev->dev, "calibration failed\n");
+
+	platform_set_drvdata(pdev, indio_dev);
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto err_hw;
+
+	return 0;
+
+err_hw:
+	meson_sar_adc_hw_disable(indio_dev);
+err:
+	return ret;
+}
+
+static int meson_sar_adc_remove(struct platform_device *pdev)
+{
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+
+	iio_device_unregister(indio_dev);
+
+	return meson_sar_adc_hw_disable(indio_dev);
+}
+
+static int __maybe_unused meson_sar_adc_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+
+	return meson_sar_adc_hw_disable(indio_dev);
+}
+
+static int __maybe_unused meson_sar_adc_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+
+	return meson_sar_adc_hw_enable(indio_dev);
+}
+
+static SIMPLE_DEV_PM_OPS(meson_sar_adc_pm_ops,
+			 meson_sar_adc_suspend, meson_sar_adc_resume);
+
+static struct platform_driver meson_sar_adc_driver = {
+	.probe		= meson_sar_adc_probe,
+	.remove		= meson_sar_adc_remove,
+	.driver		= {
+		.name	= "meson-saradc",
+		.of_match_table = meson_sar_adc_of_match,
+		.pm = &meson_sar_adc_pm_ops,
+	},
+};
+
+module_platform_driver(meson_sar_adc_driver);
+
+MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
+MODULE_DESCRIPTION("Amlogic Meson SAR ADC driver");
+MODULE_LICENSE("GPL v2");