Merge tag 'staging-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging and IIO updates from Greg KH:
 "Here are the big staging/iio patches for 4.19-rc1.

  Lots of churn here, with tons of cleanups happening in staging
  drivers, a removal of an old crypto driver that no one was using
  (skein), and the addition of some new IIO drivers. Also added was a
  "gasket" driver from Google that needs loads of work and the erofs
  filesystem.

  Even with adding all of the new drivers and a new filesystem, we are
  only adding about 1000 lines overall to the kernel linecount, which
  shows just how much cleanup happened, and how big the unused crypto
  driver was.

  All of these have been in the linux-next tree for a while now with no
  reported issues"

* tag 'staging-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (903 commits)
  staging:rtl8192u: Remove unused macro definitions - Style
  staging:rtl8192u: Add spaces around '+' operator - Style
  staging:rtl8192u: Remove stale comment - Style
  staging: rtl8188eu: remove unused mp_custom_oid.h
  staging: fbtft: Add spaces around / - Style
  staging: fbtft: Erases some repetitive usage of function name - Style
  staging: fbtft: Adjust some empty-line problems - Style
  staging: fbtft: Removes one nesting level to help readability - Style
  staging: fbtft: Changes gamma table to define.
  staging: fbtft: A bit more information on dev_err.
  staging: fbtft: Fixes some alignment issues - Style
  staging: fbtft: Puts macro arguments in parenthesis to avoid precedence issues - Style
  staging: rtl8188eu: remove unused array dB_Invert_Table
  staging: rtl8188eu: remove whitespace, add missing blank line
  staging: rtl8188eu: use is_multicast_ether_addr in rtw_sta_mgt.c
  staging: rtl8188eu: remove whitespace - style
  staging: rtl8188eu: cleanup block comment - style
  staging: rtl8188eu: use is_multicast_ether_addr in rtl8188eu_xmit.c
  staging: rtl8188eu: use is_multicast_ether_addr in recv_linux.c
  staging: rtlwifi: refactor rtl_get_tcb_desc
  ...

12 files changed, 1361 insertions, 124 deletions

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 9da79070357c..4a754921fb6f 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -157,7 +157,6 @@ config AT91_SAMA5D2_ADC
 	tristate "Atmel AT91 SAMA5D2 ADC"
 	depends on ARCH_AT91 || COMPILE_TEST
 	depends on HAS_IOMEM
-	depends on HAS_DMA
 	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
 	help
@@ -621,6 +620,16 @@ config ROCKCHIP_SARADC
 	  To compile this driver as a module, choose M here: the
 	  module will be called rockchip_saradc.
 
+config SC27XX_ADC
+	tristate "Spreadtrum SC27xx series PMICs ADC"
+	depends on MFD_SC27XX_PMIC || COMPILE_TEST
+	help
+	  Say yes here to build support for the integrated ADC inside the
+	  Spreadtrum SC27xx series PMICs.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called sc27xx_adc.
+
 config SPEAR_ADC
 	tristate "ST SPEAr ADC"
 	depends on PLAT_SPEAR || COMPILE_TEST
@@ -647,7 +656,6 @@ config SD_ADC_MODULATOR
 config STM32_ADC_CORE
 	tristate "STMicroelectronics STM32 adc core"
 	depends on ARCH_STM32 || COMPILE_TEST
-	depends on HAS_DMA
 	depends on OF
 	depends on REGULATOR
 	select IIO_BUFFER
@@ -717,6 +725,7 @@ config SUN4I_GPADC
 	depends on IIO
 	depends on MFD_SUN4I_GPADC || MACH_SUN8I
 	depends on THERMAL || !THERMAL_OF
+	select REGMAP_IRQ
 	help
 	  Say yes here to build support for Allwinner (A10, A13 and A31) SoCs
 	  GPADC. This ADC provides 4 channels which can be used as an ADC or as
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 28a9423997f3..03db7b578f9c 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -59,6 +59,7 @@ obj-$(CONFIG_QCOM_SPMI_VADC) += qcom-spmi-vadc.o
 obj-$(CONFIG_QCOM_PM8XXX_XOADC) += qcom-pm8xxx-xoadc.o
 obj-$(CONFIG_RCAR_GYRO_ADC) += rcar-gyroadc.o
 obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o
+obj-$(CONFIG_SC27XX_ADC) += sc27xx_adc.o
 obj-$(CONFIG_SPEAR_ADC) += spear_adc.o
 obj-$(CONFIG_STX104) += stx104.o
 obj-$(CONFIG_SUN4I_GPADC) += sun4i-gpadc-iio.o
diff --git a/drivers/iio/adc/ad_sigma_delta.c b/drivers/iio/adc/ad_sigma_delta.c
index cf1b048b0665..fc9510716ac7 100644
--- a/drivers/iio/adc/ad_sigma_delta.c
+++ b/drivers/iio/adc/ad_sigma_delta.c
@@ -209,6 +209,7 @@ static int ad_sd_calibrate(struct ad_sigma_delta *sigma_delta,
 	unsigned int mode, unsigned int channel)
 {
 	int ret;
+	unsigned long timeout;
 
 	ret = ad_sigma_delta_set_channel(sigma_delta, channel);
 	if (ret)
@@ -224,8 +225,8 @@ static int ad_sd_calibrate(struct ad_sigma_delta *sigma_delta,
 
 	sigma_delta->irq_dis = false;
 	enable_irq(sigma_delta->spi->irq);
-	ret = wait_for_completion_timeout(&sigma_delta->completion, 2*HZ);
-	if (ret == 0) {
+	timeout = wait_for_completion_timeout(&sigma_delta->completion, 2 * HZ);
+	if (timeout == 0) {
 		sigma_delta->irq_dis = true;
 		disable_irq_nosync(sigma_delta->spi->irq);
 		ret = -EIO;
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index 8729d6524b4d..d5ea84cf6460 100644
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -102,14 +102,26 @@
 #define AT91_SAMA5D2_LCDR	0x20
 /* Interrupt Enable Register */
 #define AT91_SAMA5D2_IER	0x24
+/* Interrupt Enable Register - TS X measurement ready */
+#define AT91_SAMA5D2_IER_XRDY   BIT(20)
+/* Interrupt Enable Register - TS Y measurement ready */
+#define AT91_SAMA5D2_IER_YRDY   BIT(21)
+/* Interrupt Enable Register - TS pressure measurement ready */
+#define AT91_SAMA5D2_IER_PRDY   BIT(22)
 /* Interrupt Enable Register - general overrun error */
 #define AT91_SAMA5D2_IER_GOVRE BIT(25)
+/* Interrupt Enable Register - Pen detect */
+#define AT91_SAMA5D2_IER_PEN    BIT(29)
+/* Interrupt Enable Register - No pen detect */
+#define AT91_SAMA5D2_IER_NOPEN  BIT(30)
 /* Interrupt Disable Register */
 #define AT91_SAMA5D2_IDR	0x28
 /* Interrupt Mask Register */
 #define AT91_SAMA5D2_IMR	0x2c
 /* Interrupt Status Register */
 #define AT91_SAMA5D2_ISR	0x30
+/* Interrupt Status Register - Pen touching sense status */
+#define AT91_SAMA5D2_ISR_PENS   BIT(31)
 /* Last Channel Trigger Mode Register */
 #define AT91_SAMA5D2_LCTMR	0x34
 /* Last Channel Compare Window Register */
@@ -118,6 +130,15 @@
 #define AT91_SAMA5D2_OVER	0x3c
 /* Extended Mode Register */
 #define AT91_SAMA5D2_EMR	0x40
+/* Extended Mode Register - Oversampling rate */
+#define AT91_SAMA5D2_EMR_OSR(V)			((V) << 16)
+#define AT91_SAMA5D2_EMR_OSR_MASK		GENMASK(17, 16)
+#define AT91_SAMA5D2_EMR_OSR_1SAMPLES		0
+#define AT91_SAMA5D2_EMR_OSR_4SAMPLES		1
+#define AT91_SAMA5D2_EMR_OSR_16SAMPLES		2
+
+/* Extended Mode Register - Averaging on single trigger event */
+#define AT91_SAMA5D2_EMR_ASTE(V)		((V) << 20)
 /* Compare Window Register */
 #define AT91_SAMA5D2_CWR	0x44
 /* Channel Gain Register */
@@ -131,8 +152,38 @@
 #define AT91_SAMA5D2_CDR0	0x50
 /* Analog Control Register */
 #define AT91_SAMA5D2_ACR	0x94
+/* Analog Control Register - Pen detect sensitivity mask */
+#define AT91_SAMA5D2_ACR_PENDETSENS_MASK        GENMASK(1, 0)
+
 /* Touchscreen Mode Register */
 #define AT91_SAMA5D2_TSMR	0xb0
+/* Touchscreen Mode Register - No touch mode */
+#define AT91_SAMA5D2_TSMR_TSMODE_NONE           0
+/* Touchscreen Mode Register - 4 wire screen, no pressure measurement */
+#define AT91_SAMA5D2_TSMR_TSMODE_4WIRE_NO_PRESS 1
+/* Touchscreen Mode Register - 4 wire screen, pressure measurement */
+#define AT91_SAMA5D2_TSMR_TSMODE_4WIRE_PRESS    2
+/* Touchscreen Mode Register - 5 wire screen */
+#define AT91_SAMA5D2_TSMR_TSMODE_5WIRE          3
+/* Touchscreen Mode Register - Average samples mask */
+#define AT91_SAMA5D2_TSMR_TSAV_MASK             GENMASK(5, 4)
+/* Touchscreen Mode Register - Average samples */
+#define AT91_SAMA5D2_TSMR_TSAV(x)               ((x) << 4)
+/* Touchscreen Mode Register - Touch/trigger frequency ratio mask */
+#define AT91_SAMA5D2_TSMR_TSFREQ_MASK           GENMASK(11, 8)
+/* Touchscreen Mode Register - Touch/trigger frequency ratio */
+#define AT91_SAMA5D2_TSMR_TSFREQ(x)             ((x) << 8)
+/* Touchscreen Mode Register - Pen Debounce Time mask */
+#define AT91_SAMA5D2_TSMR_PENDBC_MASK           GENMASK(31, 28)
+/* Touchscreen Mode Register - Pen Debounce Time */
+#define AT91_SAMA5D2_TSMR_PENDBC(x)            ((x) << 28)
+/* Touchscreen Mode Register - No DMA for touch measurements */
+#define AT91_SAMA5D2_TSMR_NOTSDMA               BIT(22)
+/* Touchscreen Mode Register - Disable pen detection */
+#define AT91_SAMA5D2_TSMR_PENDET_DIS            (0 << 24)
+/* Touchscreen Mode Register - Enable pen detection */
+#define AT91_SAMA5D2_TSMR_PENDET_ENA            BIT(24)
+
 /* Touchscreen X Position Register */
 #define AT91_SAMA5D2_XPOSR	0xb4
 /* Touchscreen Y Position Register */
@@ -151,6 +202,12 @@
 #define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL 2
 /* Trigger Mode external trigger any edge */
 #define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY 3
+/* Trigger Mode internal periodic */
+#define AT91_SAMA5D2_TRGR_TRGMOD_PERIODIC 5
+/* Trigger Mode - trigger period mask */
+#define AT91_SAMA5D2_TRGR_TRGPER_MASK           GENMASK(31, 16)
+/* Trigger Mode - trigger period */
+#define AT91_SAMA5D2_TRGR_TRGPER(x)             ((x) << 16)
 
 /* Correction Select Register */
 #define AT91_SAMA5D2_COSR	0xd0
@@ -169,6 +226,22 @@
 #define AT91_SAMA5D2_SINGLE_CHAN_CNT 12
 #define AT91_SAMA5D2_DIFF_CHAN_CNT 6
 
+#define AT91_SAMA5D2_TIMESTAMP_CHAN_IDX (AT91_SAMA5D2_SINGLE_CHAN_CNT + \
+					 AT91_SAMA5D2_DIFF_CHAN_CNT + 1)
+
+#define AT91_SAMA5D2_TOUCH_X_CHAN_IDX (AT91_SAMA5D2_SINGLE_CHAN_CNT + \
+					 AT91_SAMA5D2_DIFF_CHAN_CNT * 2)
+#define AT91_SAMA5D2_TOUCH_Y_CHAN_IDX   (AT91_SAMA5D2_TOUCH_X_CHAN_IDX + 1)
+#define AT91_SAMA5D2_TOUCH_P_CHAN_IDX   (AT91_SAMA5D2_TOUCH_Y_CHAN_IDX + 1)
+#define AT91_SAMA5D2_MAX_CHAN_IDX	AT91_SAMA5D2_TOUCH_P_CHAN_IDX
+
+#define AT91_SAMA5D2_TOUCH_SAMPLE_PERIOD_US          2000    /* 2ms */
+#define AT91_SAMA5D2_TOUCH_PEN_DETECT_DEBOUNCE_US    200
+
+#define AT91_SAMA5D2_XYZ_MASK		GENMASK(11, 0)
+
+#define AT91_SAMA5D2_MAX_POS_BITS			12
+
 /*
  * Maximum number of bytes to hold conversion from all channels
  * without the timestamp.
@@ -184,6 +257,11 @@
 #define AT91_HWFIFO_MAX_SIZE_STR	"128"
 #define AT91_HWFIFO_MAX_SIZE		128
 
+/* Possible values for oversampling ratio */
+#define AT91_OSR_1SAMPLES		1
+#define AT91_OSR_4SAMPLES		4
+#define AT91_OSR_16SAMPLES		16
+
 #define AT91_SAMA5D2_CHAN_SINGLE(num, addr)				\
 	{								\
 		.type = IIO_VOLTAGE,					\
@@ -192,12 +270,13 @@
 		.scan_index = num,					\
 		.scan_type = {						\
 			.sign = 'u',					\
-			.realbits = 12,					\
+			.realbits = 14,					\
 			.storagebits = 16,				\
 		},							\
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
-		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ)|\
+				BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),	\
 		.datasheet_name = "CH"#num,				\
 		.indexed = 1,						\
 	}
@@ -212,16 +291,50 @@
 		.scan_index = num + AT91_SAMA5D2_SINGLE_CHAN_CNT,	\
 		.scan_type = {						\
 			.sign = 's',					\
-			.realbits = 12,					\
+			.realbits = 14,					\
 			.storagebits = 16,				\
 		},							\
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
-		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ)|\
+				BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),	\
 		.datasheet_name = "CH"#num"-CH"#num2,			\
 		.indexed = 1,						\
 	}
 
+#define AT91_SAMA5D2_CHAN_TOUCH(num, name, mod)				\
+	{								\
+		.type = IIO_POSITIONRELATIVE,				\
+		.modified = 1,						\
+		.channel = num,						\
+		.channel2 = mod,					\
+		.scan_index = num,					\
+		.scan_type = {						\
+			.sign = 'u',					\
+			.realbits = 12,					\
+			.storagebits = 16,				\
+		},							\
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ)|\
+				BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),	\
+		.datasheet_name = name,					\
+	}
+#define AT91_SAMA5D2_CHAN_PRESSURE(num, name)				\
+	{								\
+		.type = IIO_PRESSURE,					\
+		.channel = num,						\
+		.scan_index = num,					\
+		.scan_type = {						\
+			.sign = 'u',					\
+			.realbits = 12,					\
+			.storagebits = 16,				\
+		},							\
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ)|\
+				BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),	\
+		.datasheet_name = name,					\
+	}
+
 #define at91_adc_readl(st, reg)		readl_relaxed(st->base + reg)
 #define at91_adc_writel(st, reg, val)	writel_relaxed(val, st->base + reg)
 
@@ -260,6 +373,22 @@ struct at91_adc_dma {
 	s64				dma_ts;
 };
 
+/**
+ * at91_adc_touch - at91-sama5d2 touchscreen information struct
+ * @sample_period_val:		the value for periodic trigger interval
+ * @touching:			is the pen touching the screen or not
+ * @x_pos:			temporary placeholder for pressure computation
+ * @channels_bitmask:		bitmask with the touchscreen channels enabled
+ * @workq:			workqueue for buffer data pushing
+ */
+struct at91_adc_touch {
+	u16				sample_period_val;
+	bool				touching;
+	u16				x_pos;
+	unsigned long			channels_bitmask;
+	struct work_struct		workq;
+};
+
 struct at91_adc_state {
 	void __iomem			*base;
 	int				irq;
@@ -267,14 +396,17 @@ struct at91_adc_state {
 	struct regulator		*reg;
 	struct regulator		*vref;
 	int				vref_uv;
+	unsigned int			current_sample_rate;
 	struct iio_trigger		*trig;
 	const struct at91_adc_trigger	*selected_trig;
 	const struct iio_chan_spec	*chan;
 	bool				conversion_done;
 	u32				conversion_value;
+	unsigned int			oversampling_ratio;
 	struct at91_adc_soc_info	soc_info;
 	wait_queue_head_t		wq_data_available;
 	struct at91_adc_dma		dma_st;
+	struct at91_adc_touch		touch_st;
 	u16				buffer[AT91_BUFFER_MAX_HWORDS];
 	/*
 	 * lock to prevent concurrent 'single conversion' requests through
@@ -329,8 +461,10 @@ static const struct iio_chan_spec at91_adc_channels[] = {
 	AT91_SAMA5D2_CHAN_DIFF(6, 7, 0x68),
 	AT91_SAMA5D2_CHAN_DIFF(8, 9, 0x70),
 	AT91_SAMA5D2_CHAN_DIFF(10, 11, 0x78),
-	IIO_CHAN_SOFT_TIMESTAMP(AT91_SAMA5D2_SINGLE_CHAN_CNT
-				+ AT91_SAMA5D2_DIFF_CHAN_CNT + 1),
+	IIO_CHAN_SOFT_TIMESTAMP(AT91_SAMA5D2_TIMESTAMP_CHAN_IDX),
+	AT91_SAMA5D2_CHAN_TOUCH(AT91_SAMA5D2_TOUCH_X_CHAN_IDX, "x", IIO_MOD_X),
+	AT91_SAMA5D2_CHAN_TOUCH(AT91_SAMA5D2_TOUCH_Y_CHAN_IDX, "y", IIO_MOD_Y),
+	AT91_SAMA5D2_CHAN_PRESSURE(AT91_SAMA5D2_TOUCH_P_CHAN_IDX, "pressure"),
 };
 
 static int at91_adc_chan_xlate(struct iio_dev *indio_dev, int chan)
@@ -354,6 +488,231 @@ at91_adc_chan_get(struct iio_dev *indio_dev, int chan)
 	return indio_dev->channels + index;
 }
 
+static inline int at91_adc_of_xlate(struct iio_dev *indio_dev,
+				    const struct of_phandle_args *iiospec)
+{
+	return at91_adc_chan_xlate(indio_dev, iiospec->args[0]);
+}
+
+static void at91_adc_config_emr(struct at91_adc_state *st)
+{
+	/* configure the extended mode register */
+	unsigned int emr = at91_adc_readl(st, AT91_SAMA5D2_EMR);
+
+	/* select oversampling per single trigger event */
+	emr |= AT91_SAMA5D2_EMR_ASTE(1);
+
+	/* delete leftover content if it's the case */
+	emr &= ~AT91_SAMA5D2_EMR_OSR_MASK;
+
+	/* select oversampling ratio from configuration */
+	switch (st->oversampling_ratio) {
+	case AT91_OSR_1SAMPLES:
+		emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_1SAMPLES) &
+		       AT91_SAMA5D2_EMR_OSR_MASK;
+		break;
+	case AT91_OSR_4SAMPLES:
+		emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_4SAMPLES) &
+		       AT91_SAMA5D2_EMR_OSR_MASK;
+		break;
+	case AT91_OSR_16SAMPLES:
+		emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_16SAMPLES) &
+		       AT91_SAMA5D2_EMR_OSR_MASK;
+		break;
+	}
+
+	at91_adc_writel(st, AT91_SAMA5D2_EMR, emr);
+}
+
+static int at91_adc_adjust_val_osr(struct at91_adc_state *st, int *val)
+{
+	if (st->oversampling_ratio == AT91_OSR_1SAMPLES) {
+		/*
+		 * in this case we only have 12 bits of real data, but channel
+		 * is registered as 14 bits, so shift left two bits
+		 */
+		*val <<= 2;
+	} else if (st->oversampling_ratio == AT91_OSR_4SAMPLES) {
+		/*
+		 * in this case we have 13 bits of real data, but channel
+		 * is registered as 14 bits, so left shift one bit
+		 */
+		*val <<= 1;
+	}
+
+	return IIO_VAL_INT;
+}
+
+static void at91_adc_adjust_val_osr_array(struct at91_adc_state *st, void *buf,
+					  int len)
+{
+	int i = 0, val;
+	u16 *buf_u16 = (u16 *) buf;
+
+	/*
+	 * We are converting each two bytes (each sample).
+	 * First convert the byte based array to u16, and convert each sample
+	 * separately.
+	 * Each value is two bytes in an array of chars, so to not shift
+	 * more than we need, save the value separately.
+	 * len is in bytes, so divide by two to get number of samples.
+	 */
+	while (i < len / 2) {
+		val = buf_u16[i];
+		at91_adc_adjust_val_osr(st, &val);
+		buf_u16[i] = val;
+		i++;
+	}
+}
+
+static int at91_adc_configure_touch(struct at91_adc_state *st, bool state)
+{
+	u32 clk_khz = st->current_sample_rate / 1000;
+	int i = 0;
+	u16 pendbc;
+	u32 tsmr, acr;
+
+	if (!state) {
+		/* disabling touch IRQs and setting mode to no touch enabled */
+		at91_adc_writel(st, AT91_SAMA5D2_IDR,
+				AT91_SAMA5D2_IER_PEN | AT91_SAMA5D2_IER_NOPEN);
+		at91_adc_writel(st, AT91_SAMA5D2_TSMR, 0);
+		return 0;
+	}
+	/*
+	 * debounce time is in microseconds, we need it in milliseconds to
+	 * multiply with kilohertz, so, divide by 1000, but after the multiply.
+	 * round up to make sure pendbc is at least 1
+	 */
+	pendbc = round_up(AT91_SAMA5D2_TOUCH_PEN_DETECT_DEBOUNCE_US *
+			  clk_khz / 1000, 1);
+
+	/* get the required exponent */
+	while (pendbc >> i++)
+		;
+
+	pendbc = i;
+
+	tsmr = AT91_SAMA5D2_TSMR_TSMODE_4WIRE_PRESS;
+
+	tsmr |= AT91_SAMA5D2_TSMR_TSAV(2) & AT91_SAMA5D2_TSMR_TSAV_MASK;
+	tsmr |= AT91_SAMA5D2_TSMR_PENDBC(pendbc) &
+		AT91_SAMA5D2_TSMR_PENDBC_MASK;
+	tsmr |= AT91_SAMA5D2_TSMR_NOTSDMA;
+	tsmr |= AT91_SAMA5D2_TSMR_PENDET_ENA;
+	tsmr |= AT91_SAMA5D2_TSMR_TSFREQ(2) & AT91_SAMA5D2_TSMR_TSFREQ_MASK;
+
+	at91_adc_writel(st, AT91_SAMA5D2_TSMR, tsmr);
+
+	acr =  at91_adc_readl(st, AT91_SAMA5D2_ACR);
+	acr &= ~AT91_SAMA5D2_ACR_PENDETSENS_MASK;
+	acr |= 0x02 & AT91_SAMA5D2_ACR_PENDETSENS_MASK;
+	at91_adc_writel(st, AT91_SAMA5D2_ACR, acr);
+
+	/* Sample Period Time = (TRGPER + 1) / ADCClock */
+	st->touch_st.sample_period_val =
+				 round_up((AT91_SAMA5D2_TOUCH_SAMPLE_PERIOD_US *
+				 clk_khz / 1000) - 1, 1);
+	/* enable pen detect IRQ */
+	at91_adc_writel(st, AT91_SAMA5D2_IER, AT91_SAMA5D2_IER_PEN);
+
+	return 0;
+}
+
+static u16 at91_adc_touch_pos(struct at91_adc_state *st, int reg)
+{
+	u32 val;
+	u32 scale, result, pos;
+
+	/*
+	 * to obtain the actual position we must divide by scale
+	 * and multiply with max, where
+	 * max = 2^AT91_SAMA5D2_MAX_POS_BITS - 1
+	 */
+	/* first half of register is the x or y, second half is the scale */
+	val = at91_adc_readl(st, reg);
+	if (!val)
+		dev_dbg(&iio_priv_to_dev(st)->dev, "pos is 0\n");
+
+	pos = val & AT91_SAMA5D2_XYZ_MASK;
+	result = (pos << AT91_SAMA5D2_MAX_POS_BITS) - pos;
+	scale = (val >> 16) & AT91_SAMA5D2_XYZ_MASK;
+	if (scale == 0) {
+		dev_err(&iio_priv_to_dev(st)->dev, "scale is 0\n");
+		return 0;
+	}
+	result /= scale;
+
+	return result;
+}
+
+static u16 at91_adc_touch_x_pos(struct at91_adc_state *st)
+{
+	st->touch_st.x_pos = at91_adc_touch_pos(st, AT91_SAMA5D2_XPOSR);
+	return st->touch_st.x_pos;
+}
+
+static u16 at91_adc_touch_y_pos(struct at91_adc_state *st)
+{
+	return at91_adc_touch_pos(st, AT91_SAMA5D2_YPOSR);
+}
+
+static u16 at91_adc_touch_pressure(struct at91_adc_state *st)
+{
+	u32 val;
+	u32 z1, z2;
+	u32 pres;
+	u32 rxp = 1;
+	u32 factor = 1000;
+
+	/* calculate the pressure */
+	val = at91_adc_readl(st, AT91_SAMA5D2_PRESSR);
+	z1 = val & AT91_SAMA5D2_XYZ_MASK;
+	z2 = (val >> 16) & AT91_SAMA5D2_XYZ_MASK;
+
+	if (z1 != 0)
+		pres = rxp * (st->touch_st.x_pos * factor / 1024) *
+			(z2 * factor / z1 - factor) /
+			factor;
+	else
+		pres = 0xFFFF;       /* no pen contact */
+
+	/*
+	 * The pressure from device grows down, minimum is 0xFFFF, maximum 0x0.
+	 * We compute it this way, but let's return it in the expected way,
+	 * growing from 0 to 0xFFFF.
+	 */
+	return 0xFFFF - pres;
+}
+
+static int at91_adc_read_position(struct at91_adc_state *st, int chan, u16 *val)
+{
+	*val = 0;
+	if (!st->touch_st.touching)
+		return -ENODATA;
+	if (chan == AT91_SAMA5D2_TOUCH_X_CHAN_IDX)
+		*val = at91_adc_touch_x_pos(st);
+	else if (chan == AT91_SAMA5D2_TOUCH_Y_CHAN_IDX)
+		*val = at91_adc_touch_y_pos(st);
+	else
+		return -ENODATA;
+
+	return IIO_VAL_INT;
+}
+
+static int at91_adc_read_pressure(struct at91_adc_state *st, int chan, u16 *val)
+{
+	*val = 0;
+	if (!st->touch_st.touching)
+		return -ENODATA;
+	if (chan == AT91_SAMA5D2_TOUCH_P_CHAN_IDX)
+		*val = at91_adc_touch_pressure(st);
+	else
+		return -ENODATA;
+
+	return IIO_VAL_INT;
+}
+
 static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
 {
 	struct iio_dev *indio = iio_trigger_get_drvdata(trig);
@@ -375,6 +734,11 @@ static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
 
 		if (!chan)
 			continue;
+		/* these channel types cannot be handled by this trigger */
+		if (chan->type == IIO_POSITIONRELATIVE ||
+		    chan->type == IIO_PRESSURE)
+			continue;
+
 		if (state) {
 			at91_adc_writel(st, AT91_SAMA5D2_CHER,
 					BIT(chan->channel));
@@ -520,7 +884,20 @@ static int at91_adc_dma_start(struct iio_dev *indio_dev)
 static int at91_adc_buffer_postenable(struct iio_dev *indio_dev)
 {
 	int ret;
+	struct at91_adc_state *st = iio_priv(indio_dev);
 
+	/* check if we are enabling triggered buffer or the touchscreen */
+	if (bitmap_subset(indio_dev->active_scan_mask,
+			  &st->touch_st.channels_bitmask,
+			  AT91_SAMA5D2_MAX_CHAN_IDX + 1)) {
+		/* touchscreen enabling */
+		return at91_adc_configure_touch(st, true);
+	}
+	/* if we are not in triggered mode, we cannot enable the buffer. */
+	if (!(indio_dev->currentmode & INDIO_ALL_TRIGGERED_MODES))
+		return -EINVAL;
+
+	/* we continue with the triggered buffer */
 	ret = at91_adc_dma_start(indio_dev);
 	if (ret) {
 		dev_err(&indio_dev->dev, "buffer postenable failed\n");
@@ -536,6 +913,18 @@ static int at91_adc_buffer_predisable(struct iio_dev *indio_dev)
 	int ret;
 	u8 bit;
 
+	/* check if we are disabling triggered buffer or the touchscreen */
+	if (bitmap_subset(indio_dev->active_scan_mask,
+			  &st->touch_st.channels_bitmask,
+			  AT91_SAMA5D2_MAX_CHAN_IDX + 1)) {
+		/* touchscreen disable */
+		return at91_adc_configure_touch(st, false);
+	}
+	/* if we are not in triggered mode, nothing to do here */
+	if (!(indio_dev->currentmode & INDIO_ALL_TRIGGERED_MODES))
+		return -EINVAL;
+
+	/* continue with the triggered buffer */
 	ret = iio_triggered_buffer_predisable(indio_dev);
 	if (ret < 0)
 		dev_err(&indio_dev->dev, "buffer predisable failed\n");
@@ -558,6 +947,10 @@ static int at91_adc_buffer_predisable(struct iio_dev *indio_dev)
 
 		if (!chan)
 			continue;
+		/* these channel types are virtual, no need to do anything */
+		if (chan->type == IIO_POSITIONRELATIVE ||
+		    chan->type == IIO_PRESSURE)
+			continue;
 		if (st->dma_st.dma_chan)
 			at91_adc_readl(st, chan->address);
 	}
@@ -613,6 +1006,7 @@ static void at91_adc_trigger_handler_nodma(struct iio_dev *indio_dev,
 {
 	struct at91_adc_state *st = iio_priv(indio_dev);
 	int i = 0;
+	int val;
 	u8 bit;
 
 	for_each_set_bit(bit, indio_dev->active_scan_mask,
@@ -622,7 +1016,24 @@ static void at91_adc_trigger_handler_nodma(struct iio_dev *indio_dev,
 
 		if (!chan)
 			continue;
-		st->buffer[i] = at91_adc_readl(st, chan->address);
+		/*
+		 * Our external trigger only supports the voltage channels.
+		 * In case someone requested a different type of channel
+		 * just put zeroes to buffer.
+		 * This should not happen because we check the scan mode
+		 * and scan mask when we enable the buffer, and we don't allow
+		 * the buffer to start with a mixed mask (voltage and something
+		 * else).
+		 * Thus, emit a warning.
+		 */
+		if (chan->type == IIO_VOLTAGE) {
+			val = at91_adc_readl(st, chan->address);
+			at91_adc_adjust_val_osr(st, &val);
+			st->buffer[i] = val;
+		} else {
+			st->buffer[i] = 0;
+			WARN(true, "This trigger cannot handle this type of channel");
+		}
 		i++;
 	}
 	iio_push_to_buffers_with_timestamp(indio_dev, st->buffer,
@@ -654,6 +1065,14 @@ static void at91_adc_trigger_handler_dma(struct iio_dev *indio_dev)
 	interval = div_s64((ns - st->dma_st.dma_ts), sample_count);
 
 	while (transferred_len >= sample_size) {
+		/*
+		 * for all the values in the current sample,
+		 * adjust the values inside the buffer for oversampling
+		 */
+		at91_adc_adjust_val_osr_array(st,
+					&st->dma_st.rx_buf[st->dma_st.buf_idx],
+					sample_size);
+
 		iio_push_to_buffers_with_timestamp(indio_dev,
 				(st->dma_st.rx_buf + st->dma_st.buf_idx),
 				(st->dma_st.dma_ts + interval * sample_index));
@@ -688,9 +1107,20 @@ static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
 
 static int at91_adc_buffer_init(struct iio_dev *indio)
 {
-	return devm_iio_triggered_buffer_setup(&indio->dev, indio,
+	struct at91_adc_state *st = iio_priv(indio);
+
+	if (st->selected_trig->hw_trig) {
+		return devm_iio_triggered_buffer_setup(&indio->dev, indio,
 			&iio_pollfunc_store_time,
 			&at91_adc_trigger_handler, &at91_buffer_setup_ops);
+	}
+	/*
+	 * we need to prepare the buffer ops in case we will get
+	 * another buffer attached (like a callback buffer for the touchscreen)
+	 */
+	indio->setup_ops = &at91_buffer_setup_ops;
+
+	return 0;
 }
 
 static unsigned at91_adc_startup_time(unsigned startup_time_min,
@@ -736,19 +1166,83 @@ static void at91_adc_setup_samp_freq(struct at91_adc_state *st, unsigned freq)
 
 	dev_dbg(&indio_dev->dev, "freq: %u, startup: %u, prescal: %u\n",
 		freq, startup, prescal);
+	st->current_sample_rate = freq;
 }
 
-static unsigned at91_adc_get_sample_freq(struct at91_adc_state *st)
+static inline unsigned at91_adc_get_sample_freq(struct at91_adc_state *st)
 {
-	unsigned f_adc, f_per = clk_get_rate(st->per_clk);
-	unsigned mr, prescal;
+	return st->current_sample_rate;
+}
 
-	mr = at91_adc_readl(st, AT91_SAMA5D2_MR);
-	prescal = (mr >> AT91_SAMA5D2_MR_PRESCAL_OFFSET)
-		  & AT91_SAMA5D2_MR_PRESCAL_MAX;
-	f_adc = f_per / (2 * (prescal + 1));
+static void at91_adc_touch_data_handler(struct iio_dev *indio_dev)
+{
+	struct at91_adc_state *st = iio_priv(indio_dev);
+	u8 bit;
+	u16 val;
+	int i = 0;
+
+	for_each_set_bit(bit, indio_dev->active_scan_mask,
+			 AT91_SAMA5D2_MAX_CHAN_IDX + 1) {
+		struct iio_chan_spec const *chan =
+					 at91_adc_chan_get(indio_dev, bit);
+
+		if (chan->type == IIO_POSITIONRELATIVE)
+			at91_adc_read_position(st, chan->channel, &val);
+		else if (chan->type == IIO_PRESSURE)
+			at91_adc_read_pressure(st, chan->channel, &val);
+		else
+			continue;
+		st->buffer[i] = val;
+		i++;
+	}
+	/*
+	 * Schedule work to push to buffers.
+	 * This is intended to push to the callback buffer that another driver
+	 * registered. We are still in a handler from our IRQ. If we push
+	 * directly, it means the other driver has it's callback called
+	 * from our IRQ context. Which is something we better avoid.
+	 * Let's schedule it after our IRQ is completed.
+	 */
+	schedule_work(&st->touch_st.workq);
+}
+
+static void at91_adc_pen_detect_interrupt(struct at91_adc_state *st)
+{
+	at91_adc_writel(st, AT91_SAMA5D2_IDR, AT91_SAMA5D2_IER_PEN);
+	at91_adc_writel(st, AT91_SAMA5D2_IER, AT91_SAMA5D2_IER_NOPEN |
+			AT91_SAMA5D2_IER_XRDY | AT91_SAMA5D2_IER_YRDY |
+			AT91_SAMA5D2_IER_PRDY);
+	at91_adc_writel(st, AT91_SAMA5D2_TRGR,
+			AT91_SAMA5D2_TRGR_TRGMOD_PERIODIC |
+			AT91_SAMA5D2_TRGR_TRGPER(st->touch_st.sample_period_val));
+	st->touch_st.touching = true;
+}
+
+static void at91_adc_no_pen_detect_interrupt(struct at91_adc_state *st)
+{
+	struct iio_dev *indio_dev = iio_priv_to_dev(st);
+
+	at91_adc_writel(st, AT91_SAMA5D2_TRGR,
+			AT91_SAMA5D2_TRGR_TRGMOD_NO_TRIGGER);
+	at91_adc_writel(st, AT91_SAMA5D2_IDR, AT91_SAMA5D2_IER_NOPEN |
+			AT91_SAMA5D2_IER_XRDY | AT91_SAMA5D2_IER_YRDY |
+			AT91_SAMA5D2_IER_PRDY);
+	st->touch_st.touching = false;
+
+	at91_adc_touch_data_handler(indio_dev);
+
+	at91_adc_writel(st, AT91_SAMA5D2_IER, AT91_SAMA5D2_IER_PEN);
+}
+
+static void at91_adc_workq_handler(struct work_struct *workq)
+{
+	struct at91_adc_touch *touch_st = container_of(workq,
+					struct at91_adc_touch, workq);
+	struct at91_adc_state *st = container_of(touch_st,
+					struct at91_adc_state, touch_st);
+	struct iio_dev *indio_dev = iio_priv_to_dev(st);
 
-	return f_adc;
+	iio_push_to_buffers(indio_dev, st->buffer);
 }
 
 static irqreturn_t at91_adc_interrupt(int irq, void *private)
@@ -757,17 +1251,39 @@ static irqreturn_t at91_adc_interrupt(int irq, void *private)
 	struct at91_adc_state *st = iio_priv(indio);
 	u32 status = at91_adc_readl(st, AT91_SAMA5D2_ISR);
 	u32 imr = at91_adc_readl(st, AT91_SAMA5D2_IMR);
+	u32 rdy_mask = AT91_SAMA5D2_IER_XRDY | AT91_SAMA5D2_IER_YRDY |
+			AT91_SAMA5D2_IER_PRDY;
 
 	if (!(status & imr))
 		return IRQ_NONE;
-
-	if (iio_buffer_enabled(indio) && !st->dma_st.dma_chan) {
+	if (status & AT91_SAMA5D2_IER_PEN) {
+		/* pen detected IRQ */
+		at91_adc_pen_detect_interrupt(st);
+	} else if ((status & AT91_SAMA5D2_IER_NOPEN)) {
+		/* nopen detected IRQ */
+		at91_adc_no_pen_detect_interrupt(st);
+	} else if ((status & AT91_SAMA5D2_ISR_PENS) &&
+		   ((status & rdy_mask) == rdy_mask)) {
+		/* periodic trigger IRQ - during pen sense */
+		at91_adc_touch_data_handler(indio);
+	} else if (status & AT91_SAMA5D2_ISR_PENS) {
+		/*
+		 * touching, but the measurements are not ready yet.
+		 * read and ignore.
+		 */
+		status = at91_adc_readl(st, AT91_SAMA5D2_XPOSR);
+		status = at91_adc_readl(st, AT91_SAMA5D2_YPOSR);
+		status = at91_adc_readl(st, AT91_SAMA5D2_PRESSR);
+	} else if (iio_buffer_enabled(indio) && !st->dma_st.dma_chan) {
+		/* triggered buffer without DMA */
 		disable_irq_nosync(irq);
 		iio_trigger_poll(indio->trig);
 	} else if (iio_buffer_enabled(indio) && st->dma_st.dma_chan) {
+		/* triggered buffer with DMA - should not happen */
 		disable_irq_nosync(irq);
 		WARN(true, "Unexpected irq occurred\n");
 	} else if (!iio_buffer_enabled(indio)) {
+		/* software requested conversion */
 		st->conversion_value = at91_adc_readl(st, st->chan->address);
 		st->conversion_done = true;
 		wake_up_interruptible(&st->wq_data_available);
@@ -775,58 +1291,100 @@ static irqreturn_t at91_adc_interrupt(int irq, void *private)
 	return IRQ_HANDLED;
 }
 
-static int at91_adc_read_raw(struct iio_dev *indio_dev,
-			     struct iio_chan_spec const *chan,
-			     int *val, int *val2, long mask)
+static int at91_adc_read_info_raw(struct iio_dev *indio_dev,
+				  struct iio_chan_spec const *chan, int *val)
 {
 	struct at91_adc_state *st = iio_priv(indio_dev);
 	u32 cor = 0;
+	u16 tmp_val;
 	int ret;
 
-	switch (mask) {
-	case IIO_CHAN_INFO_RAW:
-		/* we cannot use software trigger if hw trigger enabled */
+	/*
+	 * Keep in mind that we cannot use software trigger or touchscreen
+	 * if external trigger is enabled
+	 */
+	if (chan->type == IIO_POSITIONRELATIVE) {
 		ret = iio_device_claim_direct_mode(indio_dev);
 		if (ret)
 			return ret;
 		mutex_lock(&st->lock);
 
-		st->chan = chan;
+		ret = at91_adc_read_position(st, chan->channel,
+					     &tmp_val);
+		*val = tmp_val;
+		mutex_unlock(&st->lock);
+		iio_device_release_direct_mode(indio_dev);
 
-		if (chan->differential)
-			cor = (BIT(chan->channel) | BIT(chan->channel2)) <<
-			      AT91_SAMA5D2_COR_DIFF_OFFSET;
-
-		at91_adc_writel(st, AT91_SAMA5D2_COR, cor);
-		at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel));
-		at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel));
-		at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_START);
-
-		ret = wait_event_interruptible_timeout(st->wq_data_available,
-						       st->conversion_done,
-						       msecs_to_jiffies(1000));
-		if (ret == 0)
-			ret = -ETIMEDOUT;
-
-		if (ret > 0) {
-			*val = st->conversion_value;
-			if (chan->scan_type.sign == 's')
-				*val = sign_extend32(*val, 11);
-			ret = IIO_VAL_INT;
-			st->conversion_done = false;
-		}
+		return at91_adc_adjust_val_osr(st, val);
+	}
+	if (chan->type == IIO_PRESSURE) {
+		ret = iio_device_claim_direct_mode(indio_dev);
+		if (ret)
+			return ret;
+		mutex_lock(&st->lock);
 
-		at91_adc_writel(st, AT91_SAMA5D2_IDR, BIT(chan->channel));
-		at91_adc_writel(st, AT91_SAMA5D2_CHDR, BIT(chan->channel));
+		ret = at91_adc_read_pressure(st, chan->channel,
+					     &tmp_val);
+		*val = tmp_val;
+		mutex_unlock(&st->lock);
+		iio_device_release_direct_mode(indio_dev);
 
-		/* Needed to ACK the DRDY interruption */
-		at91_adc_readl(st, AT91_SAMA5D2_LCDR);
+		return at91_adc_adjust_val_osr(st, val);
+	}
 
-		mutex_unlock(&st->lock);
+	/* in this case we have a voltage channel */
 
-		iio_device_release_direct_mode(indio_dev);
+	ret = iio_device_claim_direct_mode(indio_dev);
+	if (ret)
 		return ret;
+	mutex_lock(&st->lock);
+
+	st->chan = chan;
+
+	if (chan->differential)
+		cor = (BIT(chan->channel) | BIT(chan->channel2)) <<
+		      AT91_SAMA5D2_COR_DIFF_OFFSET;
+
+	at91_adc_writel(st, AT91_SAMA5D2_COR, cor);
+	at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel));
+	at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel));
+	at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_START);
+
+	ret = wait_event_interruptible_timeout(st->wq_data_available,
+					       st->conversion_done,
+					       msecs_to_jiffies(1000));
+	if (ret == 0)
+		ret = -ETIMEDOUT;
+
+	if (ret > 0) {
+		*val = st->conversion_value;
+		ret = at91_adc_adjust_val_osr(st, val);
+		if (chan->scan_type.sign == 's')
+			*val = sign_extend32(*val, 11);
+		st->conversion_done = false;
+	}
 
+	at91_adc_writel(st, AT91_SAMA5D2_IDR, BIT(chan->channel));
+	at91_adc_writel(st, AT91_SAMA5D2_CHDR, BIT(chan->channel));
+
+	/* Needed to ACK the DRDY interruption */
+	at91_adc_readl(st, AT91_SAMA5D2_LCDR);
+
+	mutex_unlock(&st->lock);
+
+	iio_device_release_direct_mode(indio_dev);
+	return ret;
+}
+
+static int at91_adc_read_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int *val, int *val2, long mask)
+{
+	struct at91_adc_state *st = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		return at91_adc_read_info_raw(indio_dev, chan, val);
 	case IIO_CHAN_INFO_SCALE:
 		*val = st->vref_uv / 1000;
 		if (chan->differential)
@@ -838,6 +1396,10 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
 		*val = at91_adc_get_sample_freq(st);
 		return IIO_VAL_INT;
 
+	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+		*val = st->oversampling_ratio;
+		return IIO_VAL_INT;
+
 	default:
 		return -EINVAL;
 	}
@@ -849,16 +1411,28 @@ static int at91_adc_write_raw(struct iio_dev *indio_dev,
 {
 	struct at91_adc_state *st = iio_priv(indio_dev);
 
-	if (mask != IIO_CHAN_INFO_SAMP_FREQ)
-		return -EINVAL;
+	switch (mask) {
+	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+		if ((val != AT91_OSR_1SAMPLES) && (val != AT91_OSR_4SAMPLES) &&
+		    (val != AT91_OSR_16SAMPLES))
+			return -EINVAL;
+		/* if no change, optimize out */
+		if (val == st->oversampling_ratio)
+			return 0;
+		st->oversampling_ratio = val;
+		/* update ratio */
+		at91_adc_config_emr(st);
+		return 0;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		if (val < st->soc_info.min_sample_rate ||
+		    val > st->soc_info.max_sample_rate)
+			return -EINVAL;
 
-	if (val < st->soc_info.min_sample_rate ||
-	    val > st->soc_info.max_sample_rate)
+		at91_adc_setup_samp_freq(st, val);
+		return 0;
+	default:
 		return -EINVAL;
-
-	at91_adc_setup_samp_freq(st, val);
-
-	return 0;
+	};
 }
 
 static void at91_adc_dma_init(struct platform_device *pdev)
@@ -974,11 +1548,23 @@ static int at91_adc_set_watermark(struct iio_dev *indio_dev, unsigned int val)
 	return 0;
 }
 
-static const struct iio_info at91_adc_info = {
-	.read_raw = &at91_adc_read_raw,
-	.write_raw = &at91_adc_write_raw,
-	.hwfifo_set_watermark = &at91_adc_set_watermark,
-};
+static int at91_adc_update_scan_mode(struct iio_dev *indio_dev,
+				     const unsigned long *scan_mask)
+{
+	struct at91_adc_state *st = iio_priv(indio_dev);
+
+	if (bitmap_subset(scan_mask, &st->touch_st.channels_bitmask,
+			  AT91_SAMA5D2_MAX_CHAN_IDX + 1))
+		return 0;
+	/*
+	 * if the new bitmap is a combination of touchscreen and regular
+	 * channels, then we are not fine
+	 */
+	if (bitmap_intersects(&st->touch_st.channels_bitmask, scan_mask,
+			      AT91_SAMA5D2_MAX_CHAN_IDX + 1))
+		return -EINVAL;
+	return 0;
+}
 
 static void at91_adc_hw_init(struct at91_adc_state *st)
 {
@@ -992,6 +1578,9 @@ static void at91_adc_hw_init(struct at91_adc_state *st)
 			AT91_SAMA5D2_MR_TRANSFER(2) | AT91_SAMA5D2_MR_ANACH);
 
 	at91_adc_setup_samp_freq(st, st->soc_info.min_sample_rate);
+
+	/* configure extended mode register */
+	at91_adc_config_emr(st);
 }
 
 static ssize_t at91_adc_get_fifo_state(struct device *dev,
@@ -1022,6 +1611,20 @@ static IIO_DEVICE_ATTR(hwfifo_watermark, 0444,
 static IIO_CONST_ATTR(hwfifo_watermark_min, "2");
 static IIO_CONST_ATTR(hwfifo_watermark_max, AT91_HWFIFO_MAX_SIZE_STR);
 
+static IIO_CONST_ATTR(oversampling_ratio_available,
+		      __stringify(AT91_OSR_1SAMPLES) " "
+		      __stringify(AT91_OSR_4SAMPLES) " "
+		      __stringify(AT91_OSR_16SAMPLES));
+
+static struct attribute *at91_adc_attributes[] = {
+	&iio_const_attr_oversampling_ratio_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group at91_adc_attribute_group = {
+	.attrs = at91_adc_attributes,
+};
+
 static const struct attribute *at91_adc_fifo_attributes[] = {
 	&iio_const_attr_hwfifo_watermark_min.dev_attr.attr,
 	&iio_const_attr_hwfifo_watermark_max.dev_attr.attr,
@@ -1030,6 +1633,15 @@ static const struct attribute *at91_adc_fifo_attributes[] = {
 	NULL,
 };
 
+static const struct iio_info at91_adc_info = {
+	.attrs = &at91_adc_attribute_group,
+	.read_raw = &at91_adc_read_raw,
+	.write_raw = &at91_adc_write_raw,
+	.update_scan_mode = &at91_adc_update_scan_mode,
+	.of_xlate = &at91_adc_of_xlate,
+	.hwfifo_set_watermark = &at91_adc_set_watermark,
+};
+
 static int at91_adc_probe(struct platform_device *pdev)
 {
 	struct iio_dev *indio_dev;
@@ -1044,13 +1656,22 @@ static int at91_adc_probe(struct platform_device *pdev)
 
 	indio_dev->dev.parent = &pdev->dev;
 	indio_dev->name = dev_name(&pdev->dev);
-	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
 	indio_dev->info = &at91_adc_info;
 	indio_dev->channels = at91_adc_channels;
 	indio_dev->num_channels = ARRAY_SIZE(at91_adc_channels);
 
 	st = iio_priv(indio_dev);
 
+	bitmap_set(&st->touch_st.channels_bitmask,
+		   AT91_SAMA5D2_TOUCH_X_CHAN_IDX, 1);
+	bitmap_set(&st->touch_st.channels_bitmask,
+		   AT91_SAMA5D2_TOUCH_Y_CHAN_IDX, 1);
+	bitmap_set(&st->touch_st.channels_bitmask,
+		   AT91_SAMA5D2_TOUCH_P_CHAN_IDX, 1);
+
+	st->oversampling_ratio = AT91_OSR_1SAMPLES;
+
 	ret = of_property_read_u32(pdev->dev.of_node,
 				   "atmel,min-sample-rate-hz",
 				   &st->soc_info.min_sample_rate);
@@ -1100,6 +1721,7 @@ static int at91_adc_probe(struct platform_device *pdev)
 
 	init_waitqueue_head(&st->wq_data_available);
 	mutex_init(&st->lock);
+	INIT_WORK(&st->touch_st.workq, at91_adc_workq_handler);
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res)
@@ -1159,13 +1781,13 @@ static int at91_adc_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, indio_dev);
 
-	if (st->selected_trig->hw_trig) {
-		ret = at91_adc_buffer_init(indio_dev);
-		if (ret < 0) {
-			dev_err(&pdev->dev, "couldn't initialize the buffer.\n");
-			goto per_clk_disable_unprepare;
-		}
+	ret = at91_adc_buffer_init(indio_dev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "couldn't initialize the buffer.\n");
+		goto per_clk_disable_unprepare;
+	}
 
+	if (st->selected_trig->hw_trig) {
 		ret = at91_adc_trigger_init(indio_dev);
 		if (ret < 0) {
 			dev_err(&pdev->dev, "couldn't setup the triggers.\n");
@@ -1272,9 +1894,20 @@ static __maybe_unused int at91_adc_resume(struct device *dev)
 	at91_adc_hw_init(st);
 
 	/* reconfiguring trigger hardware state */
-	if (iio_buffer_enabled(indio_dev))
-		at91_adc_configure_trigger(st->trig, true);
+	if (!iio_buffer_enabled(indio_dev))
+		return 0;
+
+	/* check if we are enabling triggered buffer or the touchscreen */
+	if (bitmap_subset(indio_dev->active_scan_mask,
+			  &st->touch_st.channels_bitmask,
+			  AT91_SAMA5D2_MAX_CHAN_IDX + 1)) {
+		/* touchscreen enabling */
+		return at91_adc_configure_touch(st, true);
+	} else {
+		return at91_adc_configure_trigger(st->trig, true);
+	}
 
+	/* not needed but more explicit */
 	return 0;
 
 vref_disable_resume:
diff --git a/drivers/iio/adc/hx711.c b/drivers/iio/adc/hx711.c
index 9430b54121e0..36b59d8957fb 100644
--- a/drivers/iio/adc/hx711.c
+++ b/drivers/iio/adc/hx711.c
@@ -97,6 +97,14 @@ struct hx711_data {
 	 * 2x32-bit channel + 64-bit timestamp
 	 */
 	u32			buffer[4];
+	/*
+	 * delay after a rising edge on SCK until the data is ready DOUT
+	 * this is dependent on the hx711 where the datasheet tells a
+	 * maximum value of 100 ns
+	 * but also on potential parasitic capacities on the wiring
+	 */
+	u32			data_ready_delay_ns;
+	u32			clock_frequency;
 };
 
 static int hx711_cycle(struct hx711_data *hx711_data)
@@ -110,6 +118,14 @@ static int hx711_cycle(struct hx711_data *hx711_data)
 	 */
 	preempt_disable();
 	gpiod_set_value(hx711_data->gpiod_pd_sck, 1);
+
+	/*
+	 * wait until DOUT is ready
+	 * it turned out that parasitic capacities are extending the time
+	 * until DOUT has reached it's value
+	 */
+	ndelay(hx711_data->data_ready_delay_ns);
+
 	val = gpiod_get_value(hx711_data->gpiod_dout);
 	/*
 	 * here we are not waiting for 0.2 us as suggested by the datasheet,
@@ -120,6 +136,12 @@ static int hx711_cycle(struct hx711_data *hx711_data)
 	gpiod_set_value(hx711_data->gpiod_pd_sck, 0);
 	preempt_enable();
 
+	/*
+	 * make it a square wave for addressing cases with capacitance on
+	 * PC_SCK
+	 */
+	ndelay(hx711_data->data_ready_delay_ns);
+
 	return val;
 }
 
@@ -458,6 +480,7 @@ static const struct iio_chan_spec hx711_chan_spec[] = {
 static int hx711_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
 	struct hx711_data *hx711_data;
 	struct iio_dev *indio_dev;
 	int ret;
@@ -530,6 +553,22 @@ static int hx711_probe(struct platform_device *pdev)
 	hx711_data->gain_set = 128;
 	hx711_data->gain_chan_a = 128;
 
+	hx711_data->clock_frequency = 400000;
+	ret = of_property_read_u32(np, "clock-frequency",
+					&hx711_data->clock_frequency);
+
+	/*
+	 * datasheet says the high level of PD_SCK has a maximum duration
+	 * of 50 microseconds
+	 */
+	if (hx711_data->clock_frequency < 20000) {
+		dev_warn(dev, "clock-frequency too low - assuming 400 kHz\n");
+		hx711_data->clock_frequency = 400000;
+	}
+
+	hx711_data->data_ready_delay_ns =
+				1000000000 / hx711_data->clock_frequency;
+
 	platform_set_drvdata(pdev, indio_dev);
 
 	indio_dev->name = "hx711";
diff --git a/drivers/iio/adc/ina2xx-adc.c b/drivers/iio/adc/ina2xx-adc.c
index 0635a79864bf..d1239624187d 100644
--- a/drivers/iio/adc/ina2xx-adc.c
+++ b/drivers/iio/adc/ina2xx-adc.c
@@ -30,6 +30,7 @@
 #include <linux/module.h>
 #include <linux/of_device.h>
 #include <linux/regmap.h>
+#include <linux/sched/task.h>
 #include <linux/util_macros.h>
 
 #include <linux/platform_data/ina2xx.h>
@@ -826,6 +827,7 @@ static int ina2xx_buffer_enable(struct iio_dev *indio_dev)
 {
 	struct ina2xx_chip_info *chip = iio_priv(indio_dev);
 	unsigned int sampling_us = SAMPLING_PERIOD(chip);
+	struct task_struct *task;
 
 	dev_dbg(&indio_dev->dev, "Enabling buffer w/ scan_mask %02x, freq = %d, avg =%u\n",
 		(unsigned int)(*indio_dev->active_scan_mask),
@@ -835,11 +837,17 @@ static int ina2xx_buffer_enable(struct iio_dev *indio_dev)
 	dev_dbg(&indio_dev->dev, "Async readout mode: %d\n",
 		chip->allow_async_readout);
 
-	chip->task = kthread_run(ina2xx_capture_thread, (void *)indio_dev,
-				 "%s:%d-%uus", indio_dev->name, indio_dev->id,
-				 sampling_us);
+	task = kthread_create(ina2xx_capture_thread, (void *)indio_dev,
+			      "%s:%d-%uus", indio_dev->name, indio_dev->id,
+			      sampling_us);
+	if (IS_ERR(task))
+		return PTR_ERR(task);
+
+	get_task_struct(task);
+	wake_up_process(task);
+	chip->task = task;
 
-	return PTR_ERR_OR_ZERO(chip->task);
+	return 0;
 }
 
 static int ina2xx_buffer_disable(struct iio_dev *indio_dev)
@@ -848,6 +856,7 @@ static int ina2xx_buffer_disable(struct iio_dev *indio_dev)
 
 	if (chip->task) {
 		kthread_stop(chip->task);
+		put_task_struct(chip->task);
 		chip->task = NULL;
 	}
 
diff --git a/drivers/iio/adc/max1363.c b/drivers/iio/adc/max1363.c
index 7fb4f525714a..a8d35aebee80 100644
--- a/drivers/iio/adc/max1363.c
+++ b/drivers/iio/adc/max1363.c
@@ -1577,7 +1577,6 @@ static int max1363_probe(struct i2c_client *client,
 	struct max1363_state *st;
 	struct iio_dev *indio_dev;
 	struct regulator *vref;
-	const struct of_device_id *match;
 
 	indio_dev = devm_iio_device_alloc(&client->dev,
 					  sizeof(struct max1363_state));
@@ -1604,11 +1603,8 @@ static int max1363_probe(struct i2c_client *client,
 	/* this is only used for device removal purposes */
 	i2c_set_clientdata(client, indio_dev);
 
-	match = of_match_device(of_match_ptr(max1363_of_match),
-				&client->dev);
-	if (match)
-		st->chip_info = of_device_get_match_data(&client->dev);
-	else
+	st->chip_info = of_device_get_match_data(&client->dev);
+	if (!st->chip_info)
 		st->chip_info = &max1363_chip_info_tbl[id->driver_data];
 	st->client = client;
 
diff --git a/drivers/iio/adc/meson_saradc.c b/drivers/iio/adc/meson_saradc.c
index 2948909f3ee3..da2d16dfa63e 100644
--- a/drivers/iio/adc/meson_saradc.c
+++ b/drivers/iio/adc/meson_saradc.c
@@ -922,6 +922,11 @@ static const struct meson_sar_adc_data meson_sar_adc_meson8b_data = {
 	.name = "meson-meson8b-saradc",
 };
 
+static const struct meson_sar_adc_data meson_sar_adc_meson8m2_data = {
+	.param = &meson_sar_adc_meson8_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",
@@ -952,6 +957,10 @@ static const struct of_device_id meson_sar_adc_of_match[] = {
 		.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,
 	}, {
diff --git a/drivers/iio/adc/sc27xx_adc.c b/drivers/iio/adc/sc27xx_adc.c
new file mode 100644
index 000000000000..2b60efea0c39
--- /dev/null
+++ b/drivers/iio/adc/sc27xx_adc.c
@@ -0,0 +1,522 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Spreadtrum Communications Inc.
+
+#include <linux/hwspinlock.h>
+#include <linux/iio/iio.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+/* PMIC global registers definition */
+#define SC27XX_MODULE_EN		0xc08
+#define SC27XX_MODULE_ADC_EN		BIT(5)
+#define SC27XX_ARM_CLK_EN		0xc10
+#define SC27XX_CLK_ADC_EN		BIT(5)
+#define SC27XX_CLK_ADC_CLK_EN		BIT(6)
+
+/* ADC controller registers definition */
+#define SC27XX_ADC_CTL			0x0
+#define SC27XX_ADC_CH_CFG		0x4
+#define SC27XX_ADC_DATA			0x4c
+#define SC27XX_ADC_INT_EN		0x50
+#define SC27XX_ADC_INT_CLR		0x54
+#define SC27XX_ADC_INT_STS		0x58
+#define SC27XX_ADC_INT_RAW		0x5c
+
+/* Bits and mask definition for SC27XX_ADC_CTL register */
+#define SC27XX_ADC_EN			BIT(0)
+#define SC27XX_ADC_CHN_RUN		BIT(1)
+#define SC27XX_ADC_12BIT_MODE		BIT(2)
+#define SC27XX_ADC_RUN_NUM_MASK		GENMASK(7, 4)
+#define SC27XX_ADC_RUN_NUM_SHIFT	4
+
+/* Bits and mask definition for SC27XX_ADC_CH_CFG register */
+#define SC27XX_ADC_CHN_ID_MASK		GENMASK(4, 0)
+#define SC27XX_ADC_SCALE_MASK		GENMASK(10, 8)
+#define SC27XX_ADC_SCALE_SHIFT		8
+
+/* Bits definitions for SC27XX_ADC_INT_EN registers */
+#define SC27XX_ADC_IRQ_EN		BIT(0)
+
+/* Bits definitions for SC27XX_ADC_INT_CLR registers */
+#define SC27XX_ADC_IRQ_CLR		BIT(0)
+
+/* Mask definition for SC27XX_ADC_DATA register */
+#define SC27XX_ADC_DATA_MASK		GENMASK(11, 0)
+
+/* Timeout (ms) for the trylock of hardware spinlocks */
+#define SC27XX_ADC_HWLOCK_TIMEOUT	5000
+
+/* Maximum ADC channel number */
+#define SC27XX_ADC_CHANNEL_MAX		32
+
+/* ADC voltage ratio definition */
+#define SC27XX_VOLT_RATIO(n, d)		\
+	(((n) << SC27XX_RATIO_NUMERATOR_OFFSET) | (d))
+#define SC27XX_RATIO_NUMERATOR_OFFSET	16
+#define SC27XX_RATIO_DENOMINATOR_MASK	GENMASK(15, 0)
+
+struct sc27xx_adc_data {
+	struct device *dev;
+	struct regmap *regmap;
+	/*
+	 * One hardware spinlock to synchronize between the multiple
+	 * subsystems which will access the unique ADC controller.
+	 */
+	struct hwspinlock *hwlock;
+	struct completion completion;
+	int channel_scale[SC27XX_ADC_CHANNEL_MAX];
+	u32 base;
+	int value;
+	int irq;
+};
+
+struct sc27xx_adc_linear_graph {
+	int volt0;
+	int adc0;
+	int volt1;
+	int adc1;
+};
+
+/*
+ * According to the datasheet, we can convert one ADC value to one voltage value
+ * through 2 points in the linear graph. If the voltage is less than 1.2v, we
+ * should use the small-scale graph, and if more than 1.2v, we should use the
+ * big-scale graph.
+ */
+static const struct sc27xx_adc_linear_graph big_scale_graph = {
+	4200, 3310,
+	3600, 2832,
+};
+
+static const struct sc27xx_adc_linear_graph small_scale_graph = {
+	1000, 3413,
+	100, 341,
+};
+
+static int sc27xx_adc_get_ratio(int channel, int scale)
+{
+	switch (channel) {
+	case 1:
+	case 2:
+	case 3:
+	case 4:
+		return scale ? SC27XX_VOLT_RATIO(400, 1025) :
+			SC27XX_VOLT_RATIO(1, 1);
+	case 5:
+		return SC27XX_VOLT_RATIO(7, 29);
+	case 6:
+		return SC27XX_VOLT_RATIO(375, 9000);
+	case 7:
+	case 8:
+		return scale ? SC27XX_VOLT_RATIO(100, 125) :
+			SC27XX_VOLT_RATIO(1, 1);
+	case 19:
+		return SC27XX_VOLT_RATIO(1, 3);
+	default:
+		return SC27XX_VOLT_RATIO(1, 1);
+	}
+	return SC27XX_VOLT_RATIO(1, 1);
+}
+
+static int sc27xx_adc_read(struct sc27xx_adc_data *data, int channel,
+			   int scale, int *val)
+{
+	int ret;
+	u32 tmp;
+
+	reinit_completion(&data->completion);
+
+	ret = hwspin_lock_timeout_raw(data->hwlock, SC27XX_ADC_HWLOCK_TIMEOUT);
+	if (ret) {
+		dev_err(data->dev, "timeout to get the hwspinlock\n");
+		return ret;
+	}
+
+	ret = regmap_update_bits(data->regmap, data->base + SC27XX_ADC_CTL,
+				 SC27XX_ADC_EN, SC27XX_ADC_EN);
+	if (ret)
+		goto unlock_adc;
+
+	/* Configure the channel id and scale */
+	tmp = (scale << SC27XX_ADC_SCALE_SHIFT) & SC27XX_ADC_SCALE_MASK;
+	tmp |= channel & SC27XX_ADC_CHN_ID_MASK;
+	ret = regmap_update_bits(data->regmap, data->base + SC27XX_ADC_CH_CFG,
+				 SC27XX_ADC_CHN_ID_MASK | SC27XX_ADC_SCALE_MASK,
+				 tmp);
+	if (ret)
+		goto disable_adc;
+
+	/* Select 12bit conversion mode, and only sample 1 time */
+	tmp = SC27XX_ADC_12BIT_MODE;
+	tmp |= (0 << SC27XX_ADC_RUN_NUM_SHIFT) & SC27XX_ADC_RUN_NUM_MASK;
+	ret = regmap_update_bits(data->regmap, data->base + SC27XX_ADC_CTL,
+				 SC27XX_ADC_RUN_NUM_MASK | SC27XX_ADC_12BIT_MODE,
+				 tmp);
+	if (ret)
+		goto disable_adc;
+
+	ret = regmap_update_bits(data->regmap, data->base + SC27XX_ADC_CTL,
+				 SC27XX_ADC_CHN_RUN, SC27XX_ADC_CHN_RUN);
+	if (ret)
+		goto disable_adc;
+
+	wait_for_completion(&data->completion);
+
+disable_adc:
+	regmap_update_bits(data->regmap, data->base + SC27XX_ADC_CTL,
+			   SC27XX_ADC_EN, 0);
+unlock_adc:
+	hwspin_unlock_raw(data->hwlock);
+
+	if (!ret)
+		*val = data->value;
+
+	return ret;
+}
+
+static irqreturn_t sc27xx_adc_isr(int irq, void *dev_id)
+{
+	struct sc27xx_adc_data *data = dev_id;
+	int ret;
+
+	ret = regmap_update_bits(data->regmap, data->base + SC27XX_ADC_INT_CLR,
+				 SC27XX_ADC_IRQ_CLR, SC27XX_ADC_IRQ_CLR);
+	if (ret)
+		return IRQ_RETVAL(ret);
+
+	ret = regmap_read(data->regmap, data->base + SC27XX_ADC_DATA,
+			  &data->value);
+	if (ret)
+		return IRQ_RETVAL(ret);
+
+	data->value &= SC27XX_ADC_DATA_MASK;
+	complete(&data->completion);
+
+	return IRQ_HANDLED;
+}
+
+static void sc27xx_adc_volt_ratio(struct sc27xx_adc_data *data,
+				  int channel, int scale,
+				  u32 *div_numerator, u32 *div_denominator)
+{
+	u32 ratio = sc27xx_adc_get_ratio(channel, scale);
+
+	*div_numerator = ratio >> SC27XX_RATIO_NUMERATOR_OFFSET;
+	*div_denominator = ratio & SC27XX_RATIO_DENOMINATOR_MASK;
+}
+
+static int sc27xx_adc_to_volt(const struct sc27xx_adc_linear_graph *graph,
+			      int raw_adc)
+{
+	int tmp;
+
+	tmp = (graph->volt0 - graph->volt1) * (raw_adc - graph->adc1);
+	tmp /= (graph->adc0 - graph->adc1);
+	tmp += graph->volt1;
+
+	return tmp < 0 ? 0 : tmp;
+}
+
+static int sc27xx_adc_convert_volt(struct sc27xx_adc_data *data, int channel,
+				   int scale, int raw_adc)
+{
+	u32 numerator, denominator;
+	u32 volt;
+
+	/*
+	 * Convert ADC values to voltage values according to the linear graph,
+	 * and channel 5 and channel 1 has been calibrated, so we can just
+	 * return the voltage values calculated by the linear graph. But other
+	 * channels need be calculated to the real voltage values with the
+	 * voltage ratio.
+	 */
+	switch (channel) {
+	case 5:
+		return sc27xx_adc_to_volt(&big_scale_graph, raw_adc);
+
+	case 1:
+		return sc27xx_adc_to_volt(&small_scale_graph, raw_adc);
+
+	default:
+		volt = sc27xx_adc_to_volt(&small_scale_graph, raw_adc);
+		break;
+	}
+
+	sc27xx_adc_volt_ratio(data, channel, scale, &numerator, &denominator);
+
+	return (volt * denominator + numerator / 2) / numerator;
+}
+
+static int sc27xx_adc_read_processed(struct sc27xx_adc_data *data,
+				     int channel, int scale, int *val)
+{
+	int ret, raw_adc;
+
+	ret = sc27xx_adc_read(data, channel, scale, &raw_adc);
+	if (ret)
+		return ret;
+
+	*val = sc27xx_adc_convert_volt(data, channel, scale, raw_adc);
+	return 0;
+}
+
+static int sc27xx_adc_read_raw(struct iio_dev *indio_dev,
+			       struct iio_chan_spec const *chan,
+			       int *val, int *val2, long mask)
+{
+	struct sc27xx_adc_data *data = iio_priv(indio_dev);
+	int scale = data->channel_scale[chan->channel];
+	int ret, tmp;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_PROCESSED:
+		mutex_lock(&indio_dev->mlock);
+		ret = sc27xx_adc_read_processed(data, chan->channel, scale,
+						&tmp);
+		mutex_unlock(&indio_dev->mlock);
+
+		if (ret)
+			return ret;
+
+		*val = tmp;
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+		*val = scale;
+		return IIO_VAL_INT;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int sc27xx_adc_write_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *chan,
+				int val, int val2, long mask)
+{
+	struct sc27xx_adc_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		data->channel_scale[chan->channel] = val;
+		return IIO_VAL_INT;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_info sc27xx_info = {
+	.read_raw = &sc27xx_adc_read_raw,
+	.write_raw = &sc27xx_adc_write_raw,
+};
+
+#define SC27XX_ADC_CHANNEL(index) {				\
+	.type = IIO_VOLTAGE,					\
+	.channel = index,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |	\
+			      BIT(IIO_CHAN_INFO_SCALE),		\
+	.datasheet_name = "CH##index",				\
+	.indexed = 1,						\
+}
+
+static const struct iio_chan_spec sc27xx_channels[] = {
+	SC27XX_ADC_CHANNEL(0),
+	SC27XX_ADC_CHANNEL(1),
+	SC27XX_ADC_CHANNEL(2),
+	SC27XX_ADC_CHANNEL(3),
+	SC27XX_ADC_CHANNEL(4),
+	SC27XX_ADC_CHANNEL(5),
+	SC27XX_ADC_CHANNEL(6),
+	SC27XX_ADC_CHANNEL(7),
+	SC27XX_ADC_CHANNEL(8),
+	SC27XX_ADC_CHANNEL(9),
+	SC27XX_ADC_CHANNEL(10),
+	SC27XX_ADC_CHANNEL(11),
+	SC27XX_ADC_CHANNEL(12),
+	SC27XX_ADC_CHANNEL(13),
+	SC27XX_ADC_CHANNEL(14),
+	SC27XX_ADC_CHANNEL(15),
+	SC27XX_ADC_CHANNEL(16),
+	SC27XX_ADC_CHANNEL(17),
+	SC27XX_ADC_CHANNEL(18),
+	SC27XX_ADC_CHANNEL(19),
+	SC27XX_ADC_CHANNEL(20),
+	SC27XX_ADC_CHANNEL(21),
+	SC27XX_ADC_CHANNEL(22),
+	SC27XX_ADC_CHANNEL(23),
+	SC27XX_ADC_CHANNEL(24),
+	SC27XX_ADC_CHANNEL(25),
+	SC27XX_ADC_CHANNEL(26),
+	SC27XX_ADC_CHANNEL(27),
+	SC27XX_ADC_CHANNEL(28),
+	SC27XX_ADC_CHANNEL(29),
+	SC27XX_ADC_CHANNEL(30),
+	SC27XX_ADC_CHANNEL(31),
+};
+
+static int sc27xx_adc_enable(struct sc27xx_adc_data *data)
+{
+	int ret;
+
+	ret = regmap_update_bits(data->regmap, SC27XX_MODULE_EN,
+				 SC27XX_MODULE_ADC_EN, SC27XX_MODULE_ADC_EN);
+	if (ret)
+		return ret;
+
+	/* Enable ADC work clock and controller clock */
+	ret = regmap_update_bits(data->regmap, SC27XX_ARM_CLK_EN,
+				 SC27XX_CLK_ADC_EN | SC27XX_CLK_ADC_CLK_EN,
+				 SC27XX_CLK_ADC_EN | SC27XX_CLK_ADC_CLK_EN);
+	if (ret)
+		goto disable_adc;
+
+	ret = regmap_update_bits(data->regmap, data->base + SC27XX_ADC_INT_EN,
+				 SC27XX_ADC_IRQ_EN, SC27XX_ADC_IRQ_EN);
+	if (ret)
+		goto disable_clk;
+
+	return 0;
+
+disable_clk:
+	regmap_update_bits(data->regmap, SC27XX_ARM_CLK_EN,
+			   SC27XX_CLK_ADC_EN | SC27XX_CLK_ADC_CLK_EN, 0);
+disable_adc:
+	regmap_update_bits(data->regmap, SC27XX_MODULE_EN,
+			   SC27XX_MODULE_ADC_EN, 0);
+
+	return ret;
+}
+
+static void sc27xx_adc_disable(void *_data)
+{
+	struct sc27xx_adc_data *data = _data;
+
+	regmap_update_bits(data->regmap, data->base + SC27XX_ADC_INT_EN,
+			   SC27XX_ADC_IRQ_EN, 0);
+
+	/* Disable ADC work clock and controller clock */
+	regmap_update_bits(data->regmap, SC27XX_ARM_CLK_EN,
+			   SC27XX_CLK_ADC_EN | SC27XX_CLK_ADC_CLK_EN, 0);
+
+	regmap_update_bits(data->regmap, SC27XX_MODULE_EN,
+			   SC27XX_MODULE_ADC_EN, 0);
+}
+
+static void sc27xx_adc_free_hwlock(void *_data)
+{
+	struct hwspinlock *hwlock = _data;
+
+	hwspin_lock_free(hwlock);
+}
+
+static int sc27xx_adc_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct sc27xx_adc_data *sc27xx_data;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*sc27xx_data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	sc27xx_data = iio_priv(indio_dev);
+
+	sc27xx_data->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!sc27xx_data->regmap) {
+		dev_err(&pdev->dev, "failed to get ADC regmap\n");
+		return -ENODEV;
+	}
+
+	ret = of_property_read_u32(np, "reg", &sc27xx_data->base);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to get ADC base address\n");
+		return ret;
+	}
+
+	sc27xx_data->irq = platform_get_irq(pdev, 0);
+	if (sc27xx_data->irq < 0) {
+		dev_err(&pdev->dev, "failed to get ADC irq number\n");
+		return sc27xx_data->irq;
+	}
+
+	ret = of_hwspin_lock_get_id(np, 0);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to get hwspinlock id\n");
+		return ret;
+	}
+
+	sc27xx_data->hwlock = hwspin_lock_request_specific(ret);
+	if (!sc27xx_data->hwlock) {
+		dev_err(&pdev->dev, "failed to request hwspinlock\n");
+		return -ENXIO;
+	}
+
+	ret = devm_add_action(&pdev->dev, sc27xx_adc_free_hwlock,
+			      sc27xx_data->hwlock);
+	if (ret) {
+		sc27xx_adc_free_hwlock(sc27xx_data->hwlock);
+		dev_err(&pdev->dev, "failed to add hwspinlock action\n");
+		return ret;
+	}
+
+	init_completion(&sc27xx_data->completion);
+	sc27xx_data->dev = &pdev->dev;
+
+	ret = sc27xx_adc_enable(sc27xx_data);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable ADC module\n");
+		return ret;
+	}
+
+	ret = devm_add_action(&pdev->dev, sc27xx_adc_disable, sc27xx_data);
+	if (ret) {
+		sc27xx_adc_disable(sc27xx_data);
+		dev_err(&pdev->dev, "failed to add ADC disable action\n");
+		return ret;
+	}
+
+	ret = devm_request_threaded_irq(&pdev->dev, sc27xx_data->irq, NULL,
+					sc27xx_adc_isr, IRQF_ONESHOT,
+					pdev->name, sc27xx_data);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request ADC irq\n");
+		return ret;
+	}
+
+	indio_dev->dev.parent = &pdev->dev;
+	indio_dev->name = dev_name(&pdev->dev);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &sc27xx_info;
+	indio_dev->channels = sc27xx_channels;
+	indio_dev->num_channels = ARRAY_SIZE(sc27xx_channels);
+	ret = devm_iio_device_register(&pdev->dev, indio_dev);
+	if (ret)
+		dev_err(&pdev->dev, "could not register iio (ADC)");
+
+	return ret;
+}
+
+static const struct of_device_id sc27xx_adc_of_match[] = {
+	{ .compatible = "sprd,sc2731-adc", },
+	{ }
+};
+
+static struct platform_driver sc27xx_adc_driver = {
+	.probe = sc27xx_adc_probe,
+	.driver = {
+		.name = "sc27xx-adc",
+		.of_match_table = sc27xx_adc_of_match,
+	},
+};
+
+module_platform_driver(sc27xx_adc_driver);
+
+MODULE_AUTHOR("Freeman Liu <freeman.liu@spreadtrum.com>");
+MODULE_DESCRIPTION("Spreadtrum SC27XX ADC Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/adc/ti-ads7950.c b/drivers/iio/adc/ti-ads7950.c
index 0225c1b333ab..a5bd5944bc66 100644
--- a/drivers/iio/adc/ti-ads7950.c
+++ b/drivers/iio/adc/ti-ads7950.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Texas Instruments ADS7950 SPI ADC driver
  *
@@ -10,15 +11,6 @@
  * And also on hwmon/ads79xx.c
  * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com/
  *	Nishanth Menon
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation version 2.
- *
- * This program is distributed "as is" WITHOUT ANY WARRANTY of any
- * kind, whether express or implied; without even the implied warranty
- * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
  */
 
 #include <linux/acpi.h>
@@ -76,6 +68,9 @@ struct ti_ads7950_state {
 	__be16	rx_buf[TI_ADS7950_MAX_CHAN + TI_ADS7950_TIMESTAMP_SIZE]
 							____cacheline_aligned;
 	__be16	tx_buf[TI_ADS7950_MAX_CHAN];
+	__be16			single_tx;
+	__be16			single_rx;
+
 };
 
 struct ti_ads7950_chip_info {
@@ -295,18 +290,26 @@ out:
 	return IRQ_HANDLED;
 }
 
-static int ti_ads7950_scan_direct(struct ti_ads7950_state *st, unsigned int ch)
+static int ti_ads7950_scan_direct(struct iio_dev *indio_dev, unsigned int ch)
 {
+	struct ti_ads7950_state *st = iio_priv(indio_dev);
 	int ret, cmd;
 
+	mutex_lock(&indio_dev->mlock);
+
 	cmd = TI_ADS7950_CR_WRITE | TI_ADS7950_CR_CHAN(ch) | st->settings;
-	st->tx_buf[0] = cpu_to_be16(cmd);
+	st->single_tx = cpu_to_be16(cmd);
 
 	ret = spi_sync(st->spi, &st->scan_single_msg);
 	if (ret)
-		return ret;
+		goto out;
+
+	ret = be16_to_cpu(st->single_rx);
 
-	return be16_to_cpu(st->rx_buf[0]);
+out:
+	mutex_unlock(&indio_dev->mlock);
+
+	return ret;
 }
 
 static int ti_ads7950_get_range(struct ti_ads7950_state *st)
@@ -338,13 +341,7 @@ static int ti_ads7950_read_raw(struct iio_dev *indio_dev,
 
 	switch (m) {
 	case IIO_CHAN_INFO_RAW:
-
-		ret = iio_device_claim_direct_mode(indio_dev);
-		if (ret < 0)
-			return ret;
-
-		ret = ti_ads7950_scan_direct(st, chan->address);
-		iio_device_release_direct_mode(indio_dev);
+		ret = ti_ads7950_scan_direct(indio_dev, chan->address);
 		if (ret < 0)
 			return ret;
 
@@ -410,13 +407,13 @@ static int ti_ads7950_probe(struct spi_device *spi)
 	 * was read at the end of the first transfer.
 	 */
 
-	st->scan_single_xfer[0].tx_buf = &st->tx_buf[0];
+	st->scan_single_xfer[0].tx_buf = &st->single_tx;
 	st->scan_single_xfer[0].len = 2;
 	st->scan_single_xfer[0].cs_change = 1;
-	st->scan_single_xfer[1].tx_buf = &st->tx_buf[0];
+	st->scan_single_xfer[1].tx_buf = &st->single_tx;
 	st->scan_single_xfer[1].len = 2;
 	st->scan_single_xfer[1].cs_change = 1;
-	st->scan_single_xfer[2].rx_buf = &st->rx_buf[0];
+	st->scan_single_xfer[2].rx_buf = &st->single_rx;
 	st->scan_single_xfer[2].len = 2;
 
 	spi_message_init_with_transfers(&st->scan_single_msg,
diff --git a/drivers/iio/adc/xilinx-xadc-core.c b/drivers/iio/adc/xilinx-xadc-core.c
index d4f21d1be6c8..3f6be5ac049a 100644
--- a/drivers/iio/adc/xilinx-xadc-core.c
+++ b/drivers/iio/adc/xilinx-xadc-core.c
@@ -322,6 +322,7 @@ static irqreturn_t xadc_zynq_interrupt_handler(int irq, void *devid)
 
 #define XADC_ZYNQ_TCK_RATE_MAX 50000000
 #define XADC_ZYNQ_IGAP_DEFAULT 20
+#define XADC_ZYNQ_PCAP_RATE_MAX 200000000
 
 static int xadc_zynq_setup(struct platform_device *pdev,
 	struct iio_dev *indio_dev, int irq)
@@ -332,6 +333,7 @@ static int xadc_zynq_setup(struct platform_device *pdev,
 	unsigned int div;
 	unsigned int igap;
 	unsigned int tck_rate;
+	int ret;
 
 	/* TODO: Figure out how to make igap and tck_rate configurable */
 	igap = XADC_ZYNQ_IGAP_DEFAULT;
@@ -340,9 +342,16 @@ static int xadc_zynq_setup(struct platform_device *pdev,
 	xadc->zynq_intmask = ~0;
 
 	pcap_rate = clk_get_rate(xadc->clk);
+	if (!pcap_rate)
+		return -EINVAL;
+
+	if (pcap_rate > XADC_ZYNQ_PCAP_RATE_MAX) {
+		ret = clk_set_rate(xadc->clk,
+				   (unsigned long)XADC_ZYNQ_PCAP_RATE_MAX);
+		if (ret)
+			return ret;
+	}
 
-	if (tck_rate > XADC_ZYNQ_TCK_RATE_MAX)
-		tck_rate = XADC_ZYNQ_TCK_RATE_MAX;
 	if (tck_rate > pcap_rate / 2) {
 		div = 2;
 	} else {
@@ -368,6 +377,12 @@ static int xadc_zynq_setup(struct platform_device *pdev,
 			XADC_ZYNQ_CFG_REDGE | XADC_ZYNQ_CFG_WEDGE |
 			tck_div | XADC_ZYNQ_CFG_IGAP(igap));
 
+	if (pcap_rate > XADC_ZYNQ_PCAP_RATE_MAX) {
+		ret = clk_set_rate(xadc->clk, pcap_rate);
+		if (ret)
+			return ret;
+	}
+
 	return 0;
 }
 
@@ -889,6 +904,9 @@ static int xadc_write_raw(struct iio_dev *indio_dev,
 	unsigned long clk_rate = xadc_get_dclk_rate(xadc);
 	unsigned int div;
 
+	if (!clk_rate)
+		return -EINVAL;
+
 	if (info != IIO_CHAN_INFO_SAMP_FREQ)
 		return -EINVAL;
 
@@ -1045,7 +1063,7 @@ static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
 	unsigned int num_channels;
 	const char *external_mux;
 	u32 ext_mux_chan;
-	int reg;
+	u32 reg;
 	int ret;
 
 	*conf = 0;
@@ -1157,6 +1175,7 @@ static int xadc_probe(struct platform_device *pdev)
 
 	xadc = iio_priv(indio_dev);
 	xadc->ops = id->data;
+	xadc->irq = irq;
 	init_completion(&xadc->completion);
 	mutex_init(&xadc->mutex);
 	spin_lock_init(&xadc->lock);
@@ -1207,14 +1226,14 @@ static int xadc_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_free_samplerate_trigger;
 
-	ret = xadc->ops->setup(pdev, indio_dev, irq);
+	ret = request_irq(xadc->irq, xadc->ops->interrupt_handler, 0,
+			dev_name(&pdev->dev), indio_dev);
 	if (ret)
 		goto err_clk_disable_unprepare;
 
-	ret = request_irq(irq, xadc->ops->interrupt_handler, 0,
-			dev_name(&pdev->dev), indio_dev);
+	ret = xadc->ops->setup(pdev, indio_dev, xadc->irq);
 	if (ret)
-		goto err_clk_disable_unprepare;
+		goto err_free_irq;
 
 	for (i = 0; i < 16; i++)
 		xadc_read_adc_reg(xadc, XADC_REG_THRESHOLD(i),
@@ -1239,8 +1258,10 @@ static int xadc_probe(struct platform_device *pdev)
 		goto err_free_irq;
 
 	/* Disable all alarms */
-	xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_ALARM_MASK,
-		XADC_CONF1_ALARM_MASK);
+	ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_ALARM_MASK,
+				  XADC_CONF1_ALARM_MASK);
+	if (ret)
+		goto err_free_irq;
 
 	/* Set thresholds to min/max */
 	for (i = 0; i < 16; i++) {
@@ -1268,7 +1289,7 @@ static int xadc_probe(struct platform_device *pdev)
 	return 0;
 
 err_free_irq:
-	free_irq(irq, indio_dev);
+	free_irq(xadc->irq, indio_dev);
 err_clk_disable_unprepare:
 	clk_disable_unprepare(xadc->clk);
 err_free_samplerate_trigger:
@@ -1290,7 +1311,6 @@ static int xadc_remove(struct platform_device *pdev)
 {
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct xadc *xadc = iio_priv(indio_dev);
-	int irq = platform_get_irq(pdev, 0);
 
 	iio_device_unregister(indio_dev);
 	if (xadc->ops->flags & XADC_FLAGS_BUFFERED) {
@@ -1298,7 +1318,7 @@ static int xadc_remove(struct platform_device *pdev)
 		iio_trigger_free(xadc->convst_trigger);
 		iio_triggered_buffer_cleanup(indio_dev);
 	}
-	free_irq(irq, indio_dev);
+	free_irq(xadc->irq, indio_dev);
 	clk_disable_unprepare(xadc->clk);
 	cancel_delayed_work(&xadc->zynq_unmask_work);
 	kfree(xadc->data);
diff --git a/drivers/iio/adc/xilinx-xadc.h b/drivers/iio/adc/xilinx-xadc.h
index 62edbdae1244..8c0009585c16 100644
--- a/drivers/iio/adc/xilinx-xadc.h
+++ b/drivers/iio/adc/xilinx-xadc.h
@@ -68,6 +68,7 @@ struct xadc {
 	spinlock_t lock;
 
 	struct completion completion;
+	int irq;
 };
 
 struct xadc_ops {