Merge tag 'iio-for-4.5a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

First set of new device support, features and cleanups for IIO in the 4.5 cycle

Usual mixed bag, but the big item perhaps in this series is the DMA buffer
support added by Lars-Peter Clausen. It's been in the works for a long time
and it will be interesting to see what hardware support shows up now that
this is available.

New core features + associate cleanup.
* Add generic DMA buffer infrastructure
* Add a DMAengine framework based buffer
 Also associated minor changes.
   - Set the device buffer watermark based on the minimum watermark for all
     attached buffers rather than just the 'primary' one.
   - iio_buffer_init - only set the watermark default if one hasn't already
     been provided.  This allows simple support for devices with a fixed
     watermark.
   - read only attribute for watermark on fixed watermark devices.
   - add explicit buffer enable/disable callbacks to allow the buffer to
     do more than trivial actions when it is being turned on and off.
* IIO_VAL_INT support in write_raw_get_fmt function.

New device support
* Freescale MMA7455/7456L accelerometers
* Memsic MXC6255XC accelerometer
* ST lis2dh12 accelerometer
* TI ADS8688 ADC
* TI Palamas (twl6035/7) gpadc

New driver features
* mma8452
  - support either of the available interrupt pins to cope with the case
    where board layout has lead to a particular one being connected.

Staging graduation
* Dummy driver
  - this driver acts as both an example and a test device for those with
    out hardware to develop userspace code against.

Cleanups and minor bits and bobs.
* treewide
  - Sort out the ordering of iio_device_register/unregister vs runtime
    pm function calls so that it's all nice and consistent and not race
    prone.
  - Check sscanf return values.  None of the cases will actually happen as
    the strings are supplied internally, but best to be consistent on this.
* ad7780
  - switch over to the gpio descriptor interface and remove the now unused
    platform data which gets rid of a header entirely.
* ad7793
  - drop a pointless else statement.
* at91_adc
  - Swap kmalloc_array in for a kmalloc doing the same job.
* dummy
  - get rid of some commented out lines that snuck in during the move of
    the driver.
* lm3533-als
  - Print an error message on provision of an invalid resistance.
* mcp320x
  - Add compatible strings with vendor prefix and deprecate those with
    no vendor prefix.
* mxs-lradc
  - Use BIT macro in various places rather than shifted ones.
* pa12203001
  - Power off the chip if the registration fails.
* pulsedlight-lidar-lite
  - add runtime PM support.
* xilinx XADC
  - constify an iio_buffer_setup_ops structure.

8 files changed, 1397 insertions, 5 deletions

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 7868c744fd4b..9162dfefff30 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -275,6 +275,14 @@ config NAU7802
 	  To compile this driver as a module, choose M here: the
 	  module will be called nau7802.
 
+config PALMAS_GPADC
+	tristate "TI Palmas General Purpose ADC"
+	depends on MFD_PALMAS
+	help
+	  Palmas series pmic chip by Texas Instruments (twl6035/6037)
+	  is used in smartphones and tablets and supports a 16 channel
+	  general purpose ADC.
+
 config QCOM_SPMI_IADC
 	tristate "Qualcomm SPMI PMIC current ADC"
 	depends on SPMI
@@ -333,6 +341,16 @@ config TI_ADC128S052
 	  This driver can also be built as a module. If so, the module will be
 	  called ti-adc128s052.
 
+config TI_ADS8688
+	tristate "Texas Instruments ADS8688"
+	depends on SPI && OF
+	help
+	  If you say yes here you get support for Texas Instruments ADS8684 and
+	  and ADS8688 ADC chips
+
+	  This driver can also be built as a module. If so, the module will be
+	  called ti-ads8688.
+
 config TI_AM335X_ADC
 	tristate "TI's AM335X ADC driver"
 	depends on MFD_TI_AM335X_TSCADC
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 99b37a963a1e..91a65bf11c58 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -27,11 +27,13 @@ obj-$(CONFIG_MCP320X) += mcp320x.o
 obj-$(CONFIG_MCP3422) += mcp3422.o
 obj-$(CONFIG_MEN_Z188_ADC) += men_z188_adc.o
 obj-$(CONFIG_NAU7802) += nau7802.o
+obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o
 obj-$(CONFIG_QCOM_SPMI_IADC) += qcom-spmi-iadc.o
 obj-$(CONFIG_QCOM_SPMI_VADC) += qcom-spmi-vadc.o
 obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o
 obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
 obj-$(CONFIG_TI_ADC128S052) += ti-adc128s052.o
+obj-$(CONFIG_TI_ADS8688) += ti-ads8688.o
 obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
 obj-$(CONFIG_TWL4030_MADC) += twl4030-madc.o
 obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o
diff --git a/drivers/iio/adc/ad7793.c b/drivers/iio/adc/ad7793.c
index 4d960d3b93c0..7b07bb651671 100644
--- a/drivers/iio/adc/ad7793.c
+++ b/drivers/iio/adc/ad7793.c
@@ -478,10 +478,9 @@ static int ad7793_read_raw(struct iio_dev *indio_dev,
 				*val2 = st->
 					scale_avail[(st->conf >> 8) & 0x7][1];
 				return IIO_VAL_INT_PLUS_NANO;
-			} else {
-				/* 1170mV / 2^23 * 6 */
-				scale_uv = (1170ULL * 1000000000ULL * 6ULL);
 			}
+			/* 1170mV / 2^23 * 6 */
+			scale_uv = (1170ULL * 1000000000ULL * 6ULL);
 			break;
 		case IIO_TEMP:
 				/* 1170mV / 0.81 mV/C / 2^23 */
diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index 7b40925dd4ff..f284cd6a93d6 100644
--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -742,7 +742,7 @@ static int at91_adc_of_get_resolution(struct at91_adc_state *st,
 		return count;
 	}
 
-	resolutions = kmalloc(count * sizeof(*resolutions), GFP_KERNEL);
+	resolutions = kmalloc_array(count, sizeof(*resolutions), GFP_KERNEL);
 	if (!resolutions)
 		return -ENOMEM;
 
diff --git a/drivers/iio/adc/mcp320x.c b/drivers/iio/adc/mcp320x.c
index 8569c8e1f4b2..d1c05f6eed18 100644
--- a/drivers/iio/adc/mcp320x.c
+++ b/drivers/iio/adc/mcp320x.c
@@ -354,6 +354,7 @@ static int mcp320x_remove(struct spi_device *spi)
 
 #if defined(CONFIG_OF)
 static const struct of_device_id mcp320x_dt_ids[] = {
+	/* NOTE: The use of compatibles with no vendor prefix is deprecated. */
 	{
 		.compatible = "mcp3001",
 		.data = &mcp320x_chip_infos[mcp3001],
@@ -382,6 +383,33 @@ static const struct of_device_id mcp320x_dt_ids[] = {
 		.compatible = "mcp3301",
 		.data = &mcp320x_chip_infos[mcp3301],
 	}, {
+		.compatible = "microchip,mcp3001",
+		.data = &mcp320x_chip_infos[mcp3001],
+	}, {
+		.compatible = "microchip,mcp3002",
+		.data = &mcp320x_chip_infos[mcp3002],
+	}, {
+		.compatible = "microchip,mcp3004",
+		.data = &mcp320x_chip_infos[mcp3004],
+	}, {
+		.compatible = "microchip,mcp3008",
+		.data = &mcp320x_chip_infos[mcp3008],
+	}, {
+		.compatible = "microchip,mcp3201",
+		.data = &mcp320x_chip_infos[mcp3201],
+	}, {
+		.compatible = "microchip,mcp3202",
+		.data = &mcp320x_chip_infos[mcp3202],
+	}, {
+		.compatible = "microchip,mcp3204",
+		.data = &mcp320x_chip_infos[mcp3204],
+	}, {
+		.compatible = "microchip,mcp3208",
+		.data = &mcp320x_chip_infos[mcp3208],
+	}, {
+		.compatible = "microchip,mcp3301",
+		.data = &mcp320x_chip_infos[mcp3301],
+	}, {
 	}
 };
 MODULE_DEVICE_TABLE(of, mcp320x_dt_ids);
diff --git a/drivers/iio/adc/palmas_gpadc.c b/drivers/iio/adc/palmas_gpadc.c
new file mode 100644
index 000000000000..f42eb8a7d21f
--- /dev/null
+++ b/drivers/iio/adc/palmas_gpadc.c
@@ -0,0 +1,859 @@
+/*
+ * palmas-adc.c -- TI PALMAS GPADC.
+ *
+ * Copyright (c) 2013, NVIDIA Corporation. All rights reserved.
+ *
+ * Author: Pradeep Goudagunta <pgoudagunta@nvidia.com>
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/pm.h>
+#include <linux/mfd/palmas.h>
+#include <linux/completion.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/machine.h>
+#include <linux/iio/driver.h>
+
+#define MOD_NAME "palmas-gpadc"
+#define PALMAS_ADC_CONVERSION_TIMEOUT	(msecs_to_jiffies(5000))
+#define PALMAS_TO_BE_CALCULATED 0
+#define PALMAS_GPADC_TRIMINVALID	-1
+
+struct palmas_gpadc_info {
+/* calibration codes and regs */
+	int x1;	/* lower ideal code */
+	int x2;	/* higher ideal code */
+	int v1;	/* expected lower volt reading */
+	int v2;	/* expected higher volt reading */
+	u8 trim1_reg;	/* register number for lower trim */
+	u8 trim2_reg;	/* register number for upper trim */
+	int gain;	/* calculated from above (after reading trim regs) */
+	int offset;	/* calculated from above (after reading trim regs) */
+	int gain_error;	/* calculated from above (after reading trim regs) */
+	bool is_uncalibrated;	/* if channel has calibration data */
+};
+
+#define PALMAS_ADC_INFO(_chan, _x1, _x2, _v1, _v2, _t1, _t2, _is_uncalibrated) \
+	[PALMAS_ADC_CH_##_chan] = { \
+		.x1 = _x1, \
+		.x2 = _x2, \
+		.v1 = _v1, \
+		.v2 = _v2, \
+		.gain = PALMAS_TO_BE_CALCULATED, \
+		.offset = PALMAS_TO_BE_CALCULATED, \
+		.gain_error = PALMAS_TO_BE_CALCULATED, \
+		.trim1_reg = PALMAS_GPADC_TRIM##_t1, \
+		.trim2_reg = PALMAS_GPADC_TRIM##_t2,  \
+		.is_uncalibrated = _is_uncalibrated \
+	}
+
+static struct palmas_gpadc_info palmas_gpadc_info[] = {
+	PALMAS_ADC_INFO(IN0, 2064, 3112, 630, 950, 1, 2, false),
+	PALMAS_ADC_INFO(IN1, 2064, 3112, 630, 950, 1, 2, false),
+	PALMAS_ADC_INFO(IN2, 2064, 3112, 1260, 1900, 3, 4, false),
+	PALMAS_ADC_INFO(IN3, 2064, 3112, 630, 950, 1, 2, false),
+	PALMAS_ADC_INFO(IN4, 2064, 3112, 630, 950, 1, 2, false),
+	PALMAS_ADC_INFO(IN5, 2064, 3112, 630, 950, 1, 2, false),
+	PALMAS_ADC_INFO(IN6, 2064, 3112, 2520, 3800, 5, 6, false),
+	PALMAS_ADC_INFO(IN7, 2064, 3112, 2520, 3800, 7, 8, false),
+	PALMAS_ADC_INFO(IN8, 2064, 3112, 3150, 4750, 9, 10, false),
+	PALMAS_ADC_INFO(IN9, 2064, 3112, 5670, 8550, 11, 12, false),
+	PALMAS_ADC_INFO(IN10, 2064, 3112, 3465, 5225, 13, 14, false),
+	PALMAS_ADC_INFO(IN11, 0, 0, 0, 0, INVALID, INVALID, true),
+	PALMAS_ADC_INFO(IN12, 0, 0, 0, 0, INVALID, INVALID, true),
+	PALMAS_ADC_INFO(IN13, 0, 0, 0, 0, INVALID, INVALID, true),
+	PALMAS_ADC_INFO(IN14, 2064, 3112, 3645, 5225, 15, 16, false),
+	PALMAS_ADC_INFO(IN15, 0, 0, 0, 0, INVALID, INVALID, true),
+};
+
+/**
+ * struct palmas_gpadc - the palmas_gpadc structure
+ * @ch0_current:	channel 0 current source setting
+ *			0: 0 uA
+ *			1: 5 uA
+ *			2: 15 uA
+ *			3: 20 uA
+ * @ch3_current:	channel 0 current source setting
+ *			0: 0 uA
+ *			1: 10 uA
+ *			2: 400 uA
+ *			3: 800 uA
+ * @extended_delay:	enable the gpadc extended delay mode
+ * @auto_conversion_period:	define the auto_conversion_period
+ *
+ * This is the palmas_gpadc structure to store run-time information
+ * and pointers for this driver instance.
+ */
+
+struct palmas_gpadc {
+	struct device			*dev;
+	struct palmas			*palmas;
+	u8				ch0_current;
+	u8				ch3_current;
+	bool				extended_delay;
+	int				irq;
+	int				irq_auto_0;
+	int				irq_auto_1;
+	struct palmas_gpadc_info	*adc_info;
+	struct completion		conv_completion;
+	struct palmas_adc_wakeup_property wakeup1_data;
+	struct palmas_adc_wakeup_property wakeup2_data;
+	bool				wakeup1_enable;
+	bool				wakeup2_enable;
+	int				auto_conversion_period;
+};
+
+/*
+ * GPADC lock issue in AUTO mode.
+ * Impact: In AUTO mode, GPADC conversion can be locked after disabling AUTO
+ *	   mode feature.
+ * Details:
+ *	When the AUTO mode is the only conversion mode enabled, if the AUTO
+ *	mode feature is disabled with bit GPADC_AUTO_CTRL.  AUTO_CONV1_EN = 0
+ *	or bit GPADC_AUTO_CTRL.  AUTO_CONV0_EN = 0 during a conversion, the
+ *	conversion mechanism can be seen as locked meaning that all following
+ *	conversion will give 0 as a result.  Bit GPADC_STATUS.GPADC_AVAILABLE
+ *	will stay at 0 meaning that GPADC is busy.  An RT conversion can unlock
+ *	the GPADC.
+ *
+ * Workaround(s):
+ *	To avoid the lock mechanism, the workaround to follow before any stop
+ *	conversion request is:
+ *	Force the GPADC state machine to be ON by using the GPADC_CTRL1.
+ *		GPADC_FORCE bit = 1
+ *	Shutdown the GPADC AUTO conversion using
+ *		GPADC_AUTO_CTRL.SHUTDOWN_CONV[01] = 0.
+ *	After 100us, force the GPADC state machine to be OFF by using the
+ *		GPADC_CTRL1.  GPADC_FORCE bit = 0
+ */
+
+static int palmas_disable_auto_conversion(struct palmas_gpadc *adc)
+{
+	int ret;
+
+	ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
+			PALMAS_GPADC_CTRL1,
+			PALMAS_GPADC_CTRL1_GPADC_FORCE,
+			PALMAS_GPADC_CTRL1_GPADC_FORCE);
+	if (ret < 0) {
+		dev_err(adc->dev, "GPADC_CTRL1 update failed: %d\n", ret);
+		return ret;
+	}
+
+	ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
+			PALMAS_GPADC_AUTO_CTRL,
+			PALMAS_GPADC_AUTO_CTRL_SHUTDOWN_CONV1 |
+			PALMAS_GPADC_AUTO_CTRL_SHUTDOWN_CONV0,
+			0);
+	if (ret < 0) {
+		dev_err(adc->dev, "AUTO_CTRL update failed: %d\n", ret);
+		return ret;
+	}
+
+	udelay(100);
+
+	ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
+			PALMAS_GPADC_CTRL1,
+			PALMAS_GPADC_CTRL1_GPADC_FORCE, 0);
+	if (ret < 0)
+		dev_err(adc->dev, "GPADC_CTRL1 update failed: %d\n", ret);
+
+	return ret;
+}
+
+static irqreturn_t palmas_gpadc_irq(int irq, void *data)
+{
+	struct palmas_gpadc *adc = data;
+
+	complete(&adc->conv_completion);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t palmas_gpadc_irq_auto(int irq, void *data)
+{
+	struct palmas_gpadc *adc = data;
+
+	dev_dbg(adc->dev, "Threshold interrupt %d occurs\n", irq);
+	palmas_disable_auto_conversion(adc);
+
+	return IRQ_HANDLED;
+}
+
+static int palmas_gpadc_start_mask_interrupt(struct palmas_gpadc *adc,
+						bool mask)
+{
+	int ret;
+
+	if (!mask)
+		ret = palmas_update_bits(adc->palmas, PALMAS_INTERRUPT_BASE,
+					PALMAS_INT3_MASK,
+					PALMAS_INT3_MASK_GPADC_EOC_SW, 0);
+	else
+		ret = palmas_update_bits(adc->palmas, PALMAS_INTERRUPT_BASE,
+					PALMAS_INT3_MASK,
+					PALMAS_INT3_MASK_GPADC_EOC_SW,
+					PALMAS_INT3_MASK_GPADC_EOC_SW);
+	if (ret < 0)
+		dev_err(adc->dev, "GPADC INT MASK update failed: %d\n", ret);
+
+	return ret;
+}
+
+static int palmas_gpadc_enable(struct palmas_gpadc *adc, int adc_chan,
+			       int enable)
+{
+	unsigned int mask, val;
+	int ret;
+
+	if (enable) {
+		val = (adc->extended_delay
+			<< PALMAS_GPADC_RT_CTRL_EXTEND_DELAY_SHIFT);
+		ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
+					PALMAS_GPADC_RT_CTRL,
+					PALMAS_GPADC_RT_CTRL_EXTEND_DELAY, val);
+		if (ret < 0) {
+			dev_err(adc->dev, "RT_CTRL update failed: %d\n", ret);
+			return ret;
+		}
+
+		mask = (PALMAS_GPADC_CTRL1_CURRENT_SRC_CH0_MASK |
+			PALMAS_GPADC_CTRL1_CURRENT_SRC_CH3_MASK |
+			PALMAS_GPADC_CTRL1_GPADC_FORCE);
+		val = (adc->ch0_current
+			<< PALMAS_GPADC_CTRL1_CURRENT_SRC_CH0_SHIFT);
+		val |= (adc->ch3_current
+			<< PALMAS_GPADC_CTRL1_CURRENT_SRC_CH3_SHIFT);
+		val |= PALMAS_GPADC_CTRL1_GPADC_FORCE;
+		ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
+				PALMAS_GPADC_CTRL1, mask, val);
+		if (ret < 0) {
+			dev_err(adc->dev,
+				"Failed to update current setting: %d\n", ret);
+			return ret;
+		}
+
+		mask = (PALMAS_GPADC_SW_SELECT_SW_CONV0_SEL_MASK |
+			PALMAS_GPADC_SW_SELECT_SW_CONV_EN);
+		val = (adc_chan | PALMAS_GPADC_SW_SELECT_SW_CONV_EN);
+		ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
+				PALMAS_GPADC_SW_SELECT, mask, val);
+		if (ret < 0) {
+			dev_err(adc->dev, "SW_SELECT update failed: %d\n", ret);
+			return ret;
+		}
+	} else {
+		ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
+				PALMAS_GPADC_SW_SELECT, 0);
+		if (ret < 0)
+			dev_err(adc->dev, "SW_SELECT write failed: %d\n", ret);
+
+		ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
+				PALMAS_GPADC_CTRL1,
+				PALMAS_GPADC_CTRL1_GPADC_FORCE, 0);
+		if (ret < 0) {
+			dev_err(adc->dev, "CTRL1 update failed: %d\n", ret);
+			return ret;
+		}
+	}
+
+	return ret;
+}
+
+static int palmas_gpadc_read_prepare(struct palmas_gpadc *adc, int adc_chan)
+{
+	int ret;
+
+	ret = palmas_gpadc_enable(adc, adc_chan, true);
+	if (ret < 0)
+		return ret;
+
+	return palmas_gpadc_start_mask_interrupt(adc, 0);
+}
+
+static void palmas_gpadc_read_done(struct palmas_gpadc *adc, int adc_chan)
+{
+	palmas_gpadc_start_mask_interrupt(adc, 1);
+	palmas_gpadc_enable(adc, adc_chan, false);
+}
+
+static int palmas_gpadc_calibrate(struct palmas_gpadc *adc, int adc_chan)
+{
+	int k;
+	int d1;
+	int d2;
+	int ret;
+	int gain;
+	int x1 =  adc->adc_info[adc_chan].x1;
+	int x2 =  adc->adc_info[adc_chan].x2;
+	int v1 = adc->adc_info[adc_chan].v1;
+	int v2 = adc->adc_info[adc_chan].v2;
+
+	ret = palmas_read(adc->palmas, PALMAS_TRIM_GPADC_BASE,
+				adc->adc_info[adc_chan].trim1_reg, &d1);
+	if (ret < 0) {
+		dev_err(adc->dev, "TRIM read failed: %d\n", ret);
+		goto scrub;
+	}
+
+	ret = palmas_read(adc->palmas, PALMAS_TRIM_GPADC_BASE,
+				adc->adc_info[adc_chan].trim2_reg, &d2);
+	if (ret < 0) {
+		dev_err(adc->dev, "TRIM read failed: %d\n", ret);
+		goto scrub;
+	}
+
+	/* gain error calculation */
+	k = (1000 + (1000 * (d2 - d1)) / (x2 - x1));
+
+	/* gain calculation */
+	gain = ((v2 - v1) * 1000) / (x2 - x1);
+
+	adc->adc_info[adc_chan].gain_error = k;
+	adc->adc_info[adc_chan].gain = gain;
+	/* offset Calculation */
+	adc->adc_info[adc_chan].offset = (d1 * 1000) - ((k - 1000) * x1);
+
+scrub:
+	return ret;
+}
+
+static int palmas_gpadc_start_conversion(struct palmas_gpadc *adc, int adc_chan)
+{
+	unsigned int val;
+	int ret;
+
+	init_completion(&adc->conv_completion);
+	ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
+				PALMAS_GPADC_SW_SELECT,
+				PALMAS_GPADC_SW_SELECT_SW_START_CONV0,
+				PALMAS_GPADC_SW_SELECT_SW_START_CONV0);
+	if (ret < 0) {
+		dev_err(adc->dev, "SELECT_SW_START write failed: %d\n", ret);
+		return ret;
+	}
+
+	ret = wait_for_completion_timeout(&adc->conv_completion,
+				PALMAS_ADC_CONVERSION_TIMEOUT);
+	if (ret == 0) {
+		dev_err(adc->dev, "conversion not completed\n");
+		return -ETIMEDOUT;
+	}
+
+	ret = palmas_bulk_read(adc->palmas, PALMAS_GPADC_BASE,
+				PALMAS_GPADC_SW_CONV0_LSB, &val, 2);
+	if (ret < 0) {
+		dev_err(adc->dev, "SW_CONV0_LSB read failed: %d\n", ret);
+		return ret;
+	}
+
+	ret = val & 0xFFF;
+
+	return ret;
+}
+
+static int palmas_gpadc_get_calibrated_code(struct palmas_gpadc *adc,
+						int adc_chan, int val)
+{
+	if (!adc->adc_info[adc_chan].is_uncalibrated)
+		val  = (val*1000 - adc->adc_info[adc_chan].offset) /
+					adc->adc_info[adc_chan].gain_error;
+
+	if (val < 0) {
+		dev_err(adc->dev, "Mismatch with calibration\n");
+		return 0;
+	}
+
+	val = (val * adc->adc_info[adc_chan].gain) / 1000;
+
+	return val;
+}
+
+static int palmas_gpadc_read_raw(struct iio_dev *indio_dev,
+	struct iio_chan_spec const *chan, int *val, int *val2, long mask)
+{
+	struct  palmas_gpadc *adc = iio_priv(indio_dev);
+	int adc_chan = chan->channel;
+	int ret = 0;
+
+	if (adc_chan > PALMAS_ADC_CH_MAX)
+		return -EINVAL;
+
+	mutex_lock(&indio_dev->mlock);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+	case IIO_CHAN_INFO_PROCESSED:
+		ret = palmas_gpadc_read_prepare(adc, adc_chan);
+		if (ret < 0)
+			goto out;
+
+		ret = palmas_gpadc_start_conversion(adc, adc_chan);
+		if (ret < 0) {
+			dev_err(adc->dev,
+			"ADC start conversion failed\n");
+			goto out;
+		}
+
+		if (mask == IIO_CHAN_INFO_PROCESSED)
+			ret = palmas_gpadc_get_calibrated_code(
+							adc, adc_chan, ret);
+
+		*val = ret;
+
+		ret = IIO_VAL_INT;
+		goto out;
+	}
+
+	mutex_unlock(&indio_dev->mlock);
+	return ret;
+
+out:
+	palmas_gpadc_read_done(adc, adc_chan);
+	mutex_unlock(&indio_dev->mlock);
+
+	return ret;
+}
+
+static const struct iio_info palmas_gpadc_iio_info = {
+	.read_raw = palmas_gpadc_read_raw,
+	.driver_module = THIS_MODULE,
+};
+
+#define PALMAS_ADC_CHAN_IIO(chan, _type, chan_info)	\
+{							\
+	.datasheet_name = PALMAS_DATASHEET_NAME(chan),	\
+	.type = _type,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |	\
+			BIT(chan_info),			\
+	.indexed = 1,					\
+	.channel = PALMAS_ADC_CH_##chan,		\
+}
+
+static const struct iio_chan_spec palmas_gpadc_iio_channel[] = {
+	PALMAS_ADC_CHAN_IIO(IN0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+	PALMAS_ADC_CHAN_IIO(IN1, IIO_TEMP, IIO_CHAN_INFO_RAW),
+	PALMAS_ADC_CHAN_IIO(IN2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+	PALMAS_ADC_CHAN_IIO(IN3, IIO_TEMP, IIO_CHAN_INFO_RAW),
+	PALMAS_ADC_CHAN_IIO(IN4, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+	PALMAS_ADC_CHAN_IIO(IN5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+	PALMAS_ADC_CHAN_IIO(IN6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+	PALMAS_ADC_CHAN_IIO(IN7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+	PALMAS_ADC_CHAN_IIO(IN8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+	PALMAS_ADC_CHAN_IIO(IN9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+	PALMAS_ADC_CHAN_IIO(IN10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+	PALMAS_ADC_CHAN_IIO(IN11, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+	PALMAS_ADC_CHAN_IIO(IN12, IIO_TEMP, IIO_CHAN_INFO_RAW),
+	PALMAS_ADC_CHAN_IIO(IN13, IIO_TEMP, IIO_CHAN_INFO_RAW),
+	PALMAS_ADC_CHAN_IIO(IN14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+	PALMAS_ADC_CHAN_IIO(IN15, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
+};
+
+static int palmas_gpadc_get_adc_dt_data(struct platform_device *pdev,
+	struct palmas_gpadc_platform_data **gpadc_pdata)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct palmas_gpadc_platform_data *gp_data;
+	int ret;
+	u32 pval;
+
+	gp_data = devm_kzalloc(&pdev->dev, sizeof(*gp_data), GFP_KERNEL);
+	if (!gp_data)
+		return -ENOMEM;
+
+	ret = of_property_read_u32(np, "ti,channel0-current-microamp", &pval);
+	if (!ret)
+		gp_data->ch0_current = pval;
+
+	ret = of_property_read_u32(np, "ti,channel3-current-microamp", &pval);
+	if (!ret)
+		gp_data->ch3_current = pval;
+
+	gp_data->extended_delay = of_property_read_bool(np,
+					"ti,enable-extended-delay");
+
+	*gpadc_pdata = gp_data;
+
+	return 0;
+}
+
+static int palmas_gpadc_probe(struct platform_device *pdev)
+{
+	struct palmas_gpadc *adc;
+	struct palmas_platform_data *pdata;
+	struct palmas_gpadc_platform_data *gpadc_pdata = NULL;
+	struct iio_dev *indio_dev;
+	int ret, i;
+
+	pdata = dev_get_platdata(pdev->dev.parent);
+
+	if (pdata && pdata->gpadc_pdata)
+		gpadc_pdata = pdata->gpadc_pdata;
+
+	if (!gpadc_pdata && pdev->dev.of_node) {
+		ret = palmas_gpadc_get_adc_dt_data(pdev, &gpadc_pdata);
+		if (ret < 0)
+			return ret;
+	}
+	if (!gpadc_pdata)
+		return -EINVAL;
+
+	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc));
+	if (!indio_dev) {
+		dev_err(&pdev->dev, "iio_device_alloc failed\n");
+		return -ENOMEM;
+	}
+
+	adc = iio_priv(indio_dev);
+	adc->dev = &pdev->dev;
+	adc->palmas = dev_get_drvdata(pdev->dev.parent);
+	adc->adc_info = palmas_gpadc_info;
+	init_completion(&adc->conv_completion);
+	dev_set_drvdata(&pdev->dev, indio_dev);
+
+	adc->auto_conversion_period = gpadc_pdata->auto_conversion_period_ms;
+	adc->irq = palmas_irq_get_virq(adc->palmas, PALMAS_GPADC_EOC_SW_IRQ);
+	if (adc->irq < 0) {
+		dev_err(adc->dev,
+			"get virq failed: %d\n", adc->irq);
+		ret = adc->irq;
+		goto out;
+	}
+	ret = request_threaded_irq(adc->irq, NULL,
+		palmas_gpadc_irq,
+		IRQF_ONESHOT | IRQF_EARLY_RESUME, dev_name(adc->dev),
+		adc);
+	if (ret < 0) {
+		dev_err(adc->dev,
+			"request irq %d failed: %d\n", adc->irq, ret);
+		goto out;
+	}
+
+	if (gpadc_pdata->adc_wakeup1_data) {
+		memcpy(&adc->wakeup1_data, gpadc_pdata->adc_wakeup1_data,
+			sizeof(adc->wakeup1_data));
+		adc->wakeup1_enable = true;
+		adc->irq_auto_0 =  platform_get_irq(pdev, 1);
+		ret = request_threaded_irq(adc->irq_auto_0, NULL,
+				palmas_gpadc_irq_auto,
+				IRQF_ONESHOT | IRQF_EARLY_RESUME,
+				"palmas-adc-auto-0", adc);
+		if (ret < 0) {
+			dev_err(adc->dev, "request auto0 irq %d failed: %d\n",
+				adc->irq_auto_0, ret);
+			goto out_irq_free;
+		}
+	}
+
+	if (gpadc_pdata->adc_wakeup2_data) {
+		memcpy(&adc->wakeup2_data, gpadc_pdata->adc_wakeup2_data,
+				sizeof(adc->wakeup2_data));
+		adc->wakeup2_enable = true;
+		adc->irq_auto_1 =  platform_get_irq(pdev, 2);
+		ret = request_threaded_irq(adc->irq_auto_1, NULL,
+				palmas_gpadc_irq_auto,
+				IRQF_ONESHOT | IRQF_EARLY_RESUME,
+				"palmas-adc-auto-1", adc);
+		if (ret < 0) {
+			dev_err(adc->dev, "request auto1 irq %d failed: %d\n",
+				adc->irq_auto_1, ret);
+			goto out_irq_auto0_free;
+		}
+	}
+
+	/* set the current source 0 (value 0/5/15/20 uA => 0..3) */
+	if (gpadc_pdata->ch0_current <= 1)
+		adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_0;
+	else if (gpadc_pdata->ch0_current <= 5)
+		adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_5;
+	else if (gpadc_pdata->ch0_current <= 15)
+		adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_15;
+	else
+		adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_20;
+
+	/* set the current source 3 (value 0/10/400/800 uA => 0..3) */
+	if (gpadc_pdata->ch3_current <= 1)
+		adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_0;
+	else if (gpadc_pdata->ch3_current <= 10)
+		adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_10;
+	else if (gpadc_pdata->ch3_current <= 400)
+		adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_400;
+	else
+		adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_800;
+
+	adc->extended_delay = gpadc_pdata->extended_delay;
+
+	indio_dev->name = MOD_NAME;
+	indio_dev->dev.parent = &pdev->dev;
+	indio_dev->info = &palmas_gpadc_iio_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = palmas_gpadc_iio_channel;
+	indio_dev->num_channels = ARRAY_SIZE(palmas_gpadc_iio_channel);
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0) {
+		dev_err(adc->dev, "iio_device_register() failed: %d\n", ret);
+		goto out_irq_auto1_free;
+	}
+
+	device_set_wakeup_capable(&pdev->dev, 1);
+	for (i = 0; i < PALMAS_ADC_CH_MAX; i++) {
+		if (!(adc->adc_info[i].is_uncalibrated))
+			palmas_gpadc_calibrate(adc, i);
+	}
+
+	if (adc->wakeup1_enable || adc->wakeup2_enable)
+		device_wakeup_enable(&pdev->dev);
+
+	return 0;
+
+out_irq_auto1_free:
+	if (gpadc_pdata->adc_wakeup2_data)
+		free_irq(adc->irq_auto_1, adc);
+out_irq_auto0_free:
+	if (gpadc_pdata->adc_wakeup1_data)
+		free_irq(adc->irq_auto_0, adc);
+out_irq_free:
+	free_irq(adc->irq, adc);
+out:
+	return ret;
+}
+
+static int palmas_gpadc_remove(struct platform_device *pdev)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(&pdev->dev);
+	struct palmas_gpadc *adc = iio_priv(indio_dev);
+
+	if (adc->wakeup1_enable || adc->wakeup2_enable)
+		device_wakeup_disable(&pdev->dev);
+	iio_device_unregister(indio_dev);
+	free_irq(adc->irq, adc);
+	if (adc->wakeup1_enable)
+		free_irq(adc->irq_auto_0, adc);
+	if (adc->wakeup2_enable)
+		free_irq(adc->irq_auto_1, adc);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int palmas_adc_wakeup_configure(struct palmas_gpadc *adc)
+{
+	int adc_period, conv;
+	int i;
+	int ch0 = 0, ch1 = 0;
+	int thres;
+	int ret;
+
+	adc_period = adc->auto_conversion_period;
+	for (i = 0; i < 16; ++i) {
+		if (((1000 * (1 << i)) / 32) < adc_period)
+			continue;
+	}
+	if (i > 0)
+		i--;
+	adc_period = i;
+	ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
+			PALMAS_GPADC_AUTO_CTRL,
+			PALMAS_GPADC_AUTO_CTRL_COUNTER_CONV_MASK,
+			adc_period);
+	if (ret < 0) {
+		dev_err(adc->dev, "AUTO_CTRL write failed: %d\n", ret);
+		return ret;
+	}
+
+	conv = 0;
+	if (adc->wakeup1_enable) {
+		int polarity;
+
+		ch0 = adc->wakeup1_data.adc_channel_number;
+		conv |= PALMAS_GPADC_AUTO_CTRL_AUTO_CONV0_EN;
+		if (adc->wakeup1_data.adc_high_threshold > 0) {
+			thres = adc->wakeup1_data.adc_high_threshold;
+			polarity = 0;
+		} else {
+			thres = adc->wakeup1_data.adc_low_threshold;
+			polarity = PALMAS_GPADC_THRES_CONV0_MSB_THRES_CONV0_POL;
+		}
+
+		ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
+				PALMAS_GPADC_THRES_CONV0_LSB, thres & 0xFF);
+		if (ret < 0) {
+			dev_err(adc->dev,
+				"THRES_CONV0_LSB write failed: %d\n", ret);
+			return ret;
+		}
+
+		ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
+				PALMAS_GPADC_THRES_CONV0_MSB,
+				((thres >> 8) & 0xF) | polarity);
+		if (ret < 0) {
+			dev_err(adc->dev,
+				"THRES_CONV0_MSB write failed: %d\n", ret);
+			return ret;
+		}
+	}
+
+	if (adc->wakeup2_enable) {
+		int polarity;
+
+		ch1 = adc->wakeup2_data.adc_channel_number;
+		conv |= PALMAS_GPADC_AUTO_CTRL_AUTO_CONV1_EN;
+		if (adc->wakeup2_data.adc_high_threshold > 0) {
+			thres = adc->wakeup2_data.adc_high_threshold;
+			polarity = 0;
+		} else {
+			thres = adc->wakeup2_data.adc_low_threshold;
+			polarity = PALMAS_GPADC_THRES_CONV1_MSB_THRES_CONV1_POL;
+		}
+
+		ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
+				PALMAS_GPADC_THRES_CONV1_LSB, thres & 0xFF);
+		if (ret < 0) {
+			dev_err(adc->dev,
+				"THRES_CONV1_LSB write failed: %d\n", ret);
+			return ret;
+		}
+
+		ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
+				PALMAS_GPADC_THRES_CONV1_MSB,
+				((thres >> 8) & 0xF) | polarity);
+		if (ret < 0) {
+			dev_err(adc->dev,
+				"THRES_CONV1_MSB write failed: %d\n", ret);
+			return ret;
+		}
+	}
+
+	ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
+			PALMAS_GPADC_AUTO_SELECT, (ch1 << 4) | ch0);
+	if (ret < 0) {
+		dev_err(adc->dev, "AUTO_SELECT write failed: %d\n", ret);
+		return ret;
+	}
+
+	ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
+			PALMAS_GPADC_AUTO_CTRL,
+			PALMAS_GPADC_AUTO_CTRL_AUTO_CONV1_EN |
+			PALMAS_GPADC_AUTO_CTRL_AUTO_CONV0_EN, conv);
+	if (ret < 0)
+		dev_err(adc->dev, "AUTO_CTRL write failed: %d\n", ret);
+
+	return ret;
+}
+
+static int palmas_adc_wakeup_reset(struct palmas_gpadc *adc)
+{
+	int ret;
+
+	ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
+			PALMAS_GPADC_AUTO_SELECT, 0);
+	if (ret < 0) {
+		dev_err(adc->dev, "AUTO_SELECT write failed: %d\n", ret);
+		return ret;
+	}
+
+	ret = palmas_disable_auto_conversion(adc);
+	if (ret < 0)
+		dev_err(adc->dev, "Disable auto conversion failed: %d\n", ret);
+
+	return ret;
+}
+
+static int palmas_gpadc_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct palmas_gpadc *adc = iio_priv(indio_dev);
+	int wakeup = adc->wakeup1_enable || adc->wakeup2_enable;
+	int ret;
+
+	if (!device_may_wakeup(dev) || !wakeup)
+		return 0;
+
+	ret = palmas_adc_wakeup_configure(adc);
+	if (ret < 0)
+		return ret;
+
+	if (adc->wakeup1_enable)
+		enable_irq_wake(adc->irq_auto_0);
+
+	if (adc->wakeup2_enable)
+		enable_irq_wake(adc->irq_auto_1);
+
+	return 0;
+}
+
+static int palmas_gpadc_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct palmas_gpadc *adc = iio_priv(indio_dev);
+	int wakeup = adc->wakeup1_enable || adc->wakeup2_enable;
+	int ret;
+
+	if (!device_may_wakeup(dev) || !wakeup)
+		return 0;
+
+	ret = palmas_adc_wakeup_reset(adc);
+	if (ret < 0)
+		return ret;
+
+	if (adc->wakeup1_enable)
+		disable_irq_wake(adc->irq_auto_0);
+
+	if (adc->wakeup2_enable)
+		disable_irq_wake(adc->irq_auto_1);
+
+	return 0;
+};
+#endif
+
+static const struct dev_pm_ops palmas_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(palmas_gpadc_suspend,
+				palmas_gpadc_resume)
+};
+
+static const struct of_device_id of_palmas_gpadc_match_tbl[] = {
+	{ .compatible = "ti,palmas-gpadc", },
+	{ /* end */ }
+};
+MODULE_DEVICE_TABLE(of, of_palmas_gpadc_match_tbl);
+
+static struct platform_driver palmas_gpadc_driver = {
+	.probe = palmas_gpadc_probe,
+	.remove = palmas_gpadc_remove,
+	.driver = {
+		.name = MOD_NAME,
+		.pm = &palmas_pm_ops,
+		.of_match_table = of_palmas_gpadc_match_tbl,
+	},
+};
+
+static int __init palmas_gpadc_init(void)
+{
+	return platform_driver_register(&palmas_gpadc_driver);
+}
+module_init(palmas_gpadc_init);
+
+static void __exit palmas_gpadc_exit(void)
+{
+	platform_driver_unregister(&palmas_gpadc_driver);
+}
+module_exit(palmas_gpadc_exit);
+
+MODULE_DESCRIPTION("palmas GPADC driver");
+MODULE_AUTHOR("Pradeep Goudagunta<pgoudagunta@nvidia.com>");
+MODULE_ALIAS("platform:palmas-gpadc");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/adc/ti-ads8688.c b/drivers/iio/adc/ti-ads8688.c
new file mode 100644
index 000000000000..03e907028cb6
--- /dev/null
+++ b/drivers/iio/adc/ti-ads8688.c
@@ -0,0 +1,486 @@
+/*
+ * Copyright (C) 2015 Prevas A/S
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+#include <linux/regulator/consumer.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/of.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define ADS8688_CMD_REG(x)		(x << 8)
+#define ADS8688_CMD_REG_NOOP		0x00
+#define ADS8688_CMD_REG_RST		0x85
+#define ADS8688_CMD_REG_MAN_CH(chan)	(0xC0 | (4 * chan))
+#define ADS8688_CMD_DONT_CARE_BITS	16
+
+#define ADS8688_PROG_REG(x)		(x << 9)
+#define ADS8688_PROG_REG_RANGE_CH(chan)	(0x05 + chan)
+#define ADS8688_PROG_WR_BIT		BIT(8)
+#define ADS8688_PROG_DONT_CARE_BITS	8
+
+#define ADS8688_REG_PLUSMINUS25VREF	0
+#define ADS8688_REG_PLUSMINUS125VREF	1
+#define ADS8688_REG_PLUSMINUS0625VREF	2
+#define ADS8688_REG_PLUS25VREF		5
+#define ADS8688_REG_PLUS125VREF		6
+
+#define ADS8688_VREF_MV			4096
+#define ADS8688_REALBITS		16
+
+/*
+ * enum ads8688_range - ADS8688 reference voltage range
+ * @ADS8688_PLUSMINUS25VREF: Device is configured for input range ±2.5 * VREF
+ * @ADS8688_PLUSMINUS125VREF: Device is configured for input range ±1.25 * VREF
+ * @ADS8688_PLUSMINUS0625VREF: Device is configured for input range ±0.625 * VREF
+ * @ADS8688_PLUS25VREF: Device is configured for input range 0 - 2.5 * VREF
+ * @ADS8688_PLUS125VREF: Device is configured for input range 0 - 1.25 * VREF
+ */
+enum ads8688_range {
+	ADS8688_PLUSMINUS25VREF,
+	ADS8688_PLUSMINUS125VREF,
+	ADS8688_PLUSMINUS0625VREF,
+	ADS8688_PLUS25VREF,
+	ADS8688_PLUS125VREF,
+};
+
+struct ads8688_chip_info {
+	const struct iio_chan_spec *channels;
+	unsigned int num_channels;
+};
+
+struct ads8688_state {
+	struct mutex			lock;
+	const struct ads8688_chip_info	*chip_info;
+	struct spi_device		*spi;
+	struct regulator		*reg;
+	unsigned int			vref_mv;
+	enum ads8688_range		range[8];
+	union {
+		__be32 d32;
+		u8 d8[4];
+	} data[2] ____cacheline_aligned;
+};
+
+enum ads8688_id {
+	ID_ADS8684,
+	ID_ADS8688,
+};
+
+struct ads8688_ranges {
+	enum ads8688_range range;
+	unsigned int scale;
+	int offset;
+	u8 reg;
+};
+
+static const struct ads8688_ranges ads8688_range_def[5] = {
+	{
+		.range = ADS8688_PLUSMINUS25VREF,
+		.scale = 76295,
+		.offset = -(1 << (ADS8688_REALBITS - 1)),
+		.reg = ADS8688_REG_PLUSMINUS25VREF,
+	}, {
+		.range = ADS8688_PLUSMINUS125VREF,
+		.scale = 38148,
+		.offset = -(1 << (ADS8688_REALBITS - 1)),
+		.reg = ADS8688_REG_PLUSMINUS125VREF,
+	}, {
+		.range = ADS8688_PLUSMINUS0625VREF,
+		.scale = 19074,
+		.offset = -(1 << (ADS8688_REALBITS - 1)),
+		.reg = ADS8688_REG_PLUSMINUS0625VREF,
+	}, {
+		.range = ADS8688_PLUS25VREF,
+		.scale = 38148,
+		.offset = 0,
+		.reg = ADS8688_REG_PLUS25VREF,
+	}, {
+		.range = ADS8688_PLUS125VREF,
+		.scale = 19074,
+		.offset = 0,
+		.reg = ADS8688_REG_PLUS125VREF,
+	}
+};
+
+static ssize_t ads8688_show_scales(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct ads8688_state *st = iio_priv(dev_to_iio_dev(dev));
+
+	return sprintf(buf, "0.%09u 0.%09u 0.%09u\n",
+		       ads8688_range_def[0].scale * st->vref_mv,
+		       ads8688_range_def[1].scale * st->vref_mv,
+		       ads8688_range_def[2].scale * st->vref_mv);
+}
+
+static ssize_t ads8688_show_offsets(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%d %d\n", ads8688_range_def[0].offset,
+		       ads8688_range_def[3].offset);
+}
+
+static IIO_DEVICE_ATTR(in_voltage_scale_available, S_IRUGO,
+		       ads8688_show_scales, NULL, 0);
+static IIO_DEVICE_ATTR(in_voltage_offset_available, S_IRUGO,
+		       ads8688_show_offsets, NULL, 0);
+
+static struct attribute *ads8688_attributes[] = {
+	&iio_dev_attr_in_voltage_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage_offset_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ads8688_attribute_group = {
+	.attrs = ads8688_attributes,
+};
+
+#define ADS8688_CHAN(index)					\
+{								\
+	.type = IIO_VOLTAGE,					\
+	.indexed = 1,						\
+	.channel = index,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW)		\
+			      | BIT(IIO_CHAN_INFO_SCALE)	\
+			      | BIT(IIO_CHAN_INFO_OFFSET),	\
+}
+
+static const struct iio_chan_spec ads8684_channels[] = {
+	ADS8688_CHAN(0),
+	ADS8688_CHAN(1),
+	ADS8688_CHAN(2),
+	ADS8688_CHAN(3),
+};
+
+static const struct iio_chan_spec ads8688_channels[] = {
+	ADS8688_CHAN(0),
+	ADS8688_CHAN(1),
+	ADS8688_CHAN(2),
+	ADS8688_CHAN(3),
+	ADS8688_CHAN(4),
+	ADS8688_CHAN(5),
+	ADS8688_CHAN(6),
+	ADS8688_CHAN(7),
+};
+
+static int ads8688_prog_write(struct iio_dev *indio_dev, unsigned int addr,
+			      unsigned int val)
+{
+	struct ads8688_state *st = iio_priv(indio_dev);
+	u32 tmp;
+
+	tmp = ADS8688_PROG_REG(addr) | ADS8688_PROG_WR_BIT | val;
+	tmp <<= ADS8688_PROG_DONT_CARE_BITS;
+	st->data[0].d32 = cpu_to_be32(tmp);
+
+	return spi_write(st->spi, &st->data[0].d8[1], 3);
+}
+
+static int ads8688_reset(struct iio_dev *indio_dev)
+{
+	struct ads8688_state *st = iio_priv(indio_dev);
+	u32 tmp;
+
+	tmp = ADS8688_CMD_REG(ADS8688_CMD_REG_RST);
+	tmp <<= ADS8688_CMD_DONT_CARE_BITS;
+	st->data[0].d32 = cpu_to_be32(tmp);
+
+	return spi_write(st->spi, &st->data[0].d8[0], 4);
+}
+
+static int ads8688_read(struct iio_dev *indio_dev, unsigned int chan)
+{
+	struct ads8688_state *st = iio_priv(indio_dev);
+	int ret;
+	u32 tmp;
+	struct spi_transfer t[] = {
+		{
+			.tx_buf = &st->data[0].d8[0],
+			.len = 4,
+			.cs_change = 1,
+		}, {
+			.tx_buf = &st->data[1].d8[0],
+			.rx_buf = &st->data[1].d8[0],
+			.len = 4,
+		},
+	};
+
+	tmp = ADS8688_CMD_REG(ADS8688_CMD_REG_MAN_CH(chan));
+	tmp <<= ADS8688_CMD_DONT_CARE_BITS;
+	st->data[0].d32 = cpu_to_be32(tmp);
+
+	tmp = ADS8688_CMD_REG(ADS8688_CMD_REG_NOOP);
+	tmp <<= ADS8688_CMD_DONT_CARE_BITS;
+	st->data[1].d32 = cpu_to_be32(tmp);
+
+	ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
+	if (ret < 0)
+		return ret;
+
+	return be32_to_cpu(st->data[1].d32) & 0xffff;
+}
+
+static int ads8688_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int *val, int *val2, long m)
+{
+	int ret, offset;
+	unsigned long scale_mv;
+
+	struct ads8688_state *st = iio_priv(indio_dev);
+
+	mutex_lock(&st->lock);
+	switch (m) {
+	case IIO_CHAN_INFO_RAW:
+		ret = ads8688_read(indio_dev, chan->channel);
+		mutex_unlock(&st->lock);
+		if (ret < 0)
+			return ret;
+		*val = ret;
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		scale_mv = st->vref_mv;
+		scale_mv *= ads8688_range_def[st->range[chan->channel]].scale;
+		*val = 0;
+		*val2 = scale_mv;
+		mutex_unlock(&st->lock);
+		return IIO_VAL_INT_PLUS_NANO;
+	case IIO_CHAN_INFO_OFFSET:
+		offset = ads8688_range_def[st->range[chan->channel]].offset;
+		*val = offset;
+		mutex_unlock(&st->lock);
+		return IIO_VAL_INT;
+	}
+	mutex_unlock(&st->lock);
+
+	return -EINVAL;
+}
+
+static int ads8688_write_reg_range(struct iio_dev *indio_dev,
+				   struct iio_chan_spec const *chan,
+				   enum ads8688_range range)
+{
+	unsigned int tmp;
+	int ret;
+
+	tmp = ADS8688_PROG_REG_RANGE_CH(chan->channel);
+	ret = ads8688_prog_write(indio_dev, tmp, range);
+
+	return ret;
+}
+
+static int ads8688_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int val, int val2, long mask)
+{
+	struct ads8688_state *st = iio_priv(indio_dev);
+	unsigned int scale = 0;
+	int ret = -EINVAL, i, offset = 0;
+
+	mutex_lock(&st->lock);
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		/* If the offset is 0 the ±2.5 * VREF mode is not available */
+		offset = ads8688_range_def[st->range[chan->channel]].offset;
+		if (offset == 0 && val2 == ads8688_range_def[0].scale * st->vref_mv) {
+			mutex_unlock(&st->lock);
+			return -EINVAL;
+		}
+
+		/* Lookup new mode */
+		for (i = 0; i < ARRAY_SIZE(ads8688_range_def); i++)
+			if (val2 == ads8688_range_def[i].scale * st->vref_mv &&
+			    offset == ads8688_range_def[i].offset) {
+				ret = ads8688_write_reg_range(indio_dev, chan,
+					ads8688_range_def[i].reg);
+				break;
+			}
+		break;
+	case IIO_CHAN_INFO_OFFSET:
+		/*
+		 * There are only two available offsets:
+		 * 0 and -(1 << (ADS8688_REALBITS - 1))
+		 */
+		if (!(ads8688_range_def[0].offset == val ||
+		    ads8688_range_def[3].offset == val)) {
+			mutex_unlock(&st->lock);
+			return -EINVAL;
+		}
+
+		/*
+		 * If the device are in ±2.5 * VREF mode, it's not allowed to
+		 * switch to a mode where the offset is 0
+		 */
+		if (val == 0 &&
+		    st->range[chan->channel] == ADS8688_PLUSMINUS25VREF) {
+			mutex_unlock(&st->lock);
+			return -EINVAL;
+		}
+
+		scale = ads8688_range_def[st->range[chan->channel]].scale;
+
+		/* Lookup new mode */
+		for (i = 0; i < ARRAY_SIZE(ads8688_range_def); i++)
+			if (val == ads8688_range_def[i].offset &&
+			    scale == ads8688_range_def[i].scale) {
+				ret = ads8688_write_reg_range(indio_dev, chan,
+					ads8688_range_def[i].reg);
+				break;
+			}
+		break;
+	}
+
+	if (!ret)
+		st->range[chan->channel] = ads8688_range_def[i].range;
+
+	mutex_unlock(&st->lock);
+
+	return ret;
+}
+
+static int ads8688_write_raw_get_fmt(struct iio_dev *indio_dev,
+				     struct iio_chan_spec const *chan,
+				     long mask)
+{
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		return IIO_VAL_INT_PLUS_NANO;
+	case IIO_CHAN_INFO_OFFSET:
+		return IIO_VAL_INT;
+	}
+
+	return -EINVAL;
+}
+
+static const struct iio_info ads8688_info = {
+	.read_raw = &ads8688_read_raw,
+	.write_raw = &ads8688_write_raw,
+	.write_raw_get_fmt = &ads8688_write_raw_get_fmt,
+	.attrs = &ads8688_attribute_group,
+	.driver_module = THIS_MODULE,
+};
+
+static const struct ads8688_chip_info ads8688_chip_info_tbl[] = {
+	[ID_ADS8684] = {
+		.channels = ads8684_channels,
+		.num_channels = ARRAY_SIZE(ads8684_channels),
+	},
+	[ID_ADS8688] = {
+		.channels = ads8688_channels,
+		.num_channels = ARRAY_SIZE(ads8688_channels),
+	},
+};
+
+static int ads8688_probe(struct spi_device *spi)
+{
+	struct ads8688_state *st;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+	if (indio_dev == NULL)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+
+	st->reg = devm_regulator_get_optional(&spi->dev, "vref");
+	if (!IS_ERR(st->reg)) {
+		ret = regulator_enable(st->reg);
+		if (ret)
+			return ret;
+
+		ret = regulator_get_voltage(st->reg);
+		if (ret < 0)
+			goto error_out;
+
+		st->vref_mv = ret / 1000;
+	} else {
+		/* Use internal reference */
+		st->vref_mv = ADS8688_VREF_MV;
+	}
+
+	st->chip_info =	&ads8688_chip_info_tbl[spi_get_device_id(spi)->driver_data];
+
+	spi->mode = SPI_MODE_1;
+
+	spi_set_drvdata(spi, indio_dev);
+
+	st->spi = spi;
+
+	indio_dev->name = spi_get_device_id(spi)->name;
+	indio_dev->dev.parent = &spi->dev;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = st->chip_info->channels;
+	indio_dev->num_channels = st->chip_info->num_channels;
+	indio_dev->info = &ads8688_info;
+
+	ads8688_reset(indio_dev);
+
+	mutex_init(&st->lock);
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto error_out;
+
+	return 0;
+
+error_out:
+	if (!IS_ERR_OR_NULL(st->reg))
+		regulator_disable(st->reg);
+
+	return ret;
+}
+
+static int ads8688_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct ads8688_state *st = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+
+	if (!IS_ERR_OR_NULL(st->reg))
+		regulator_disable(st->reg);
+
+	return 0;
+}
+
+static const struct spi_device_id ads8688_id[] = {
+	{"ads8684", ID_ADS8684},
+	{"ads8688", ID_ADS8688},
+	{}
+};
+MODULE_DEVICE_TABLE(spi, ads8688_id);
+
+static const struct of_device_id ads8688_of_match[] = {
+	{ .compatible = "ti,ads8684" },
+	{ .compatible = "ti,ads8688" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ads8688_of_match);
+
+static struct spi_driver ads8688_driver = {
+	.driver = {
+		.name	= "ads8688",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= ads8688_probe,
+	.remove		= ads8688_remove,
+	.id_table	= ads8688_id,
+};
+module_spi_driver(ads8688_driver);
+
+MODULE_AUTHOR("Sean Nyekjaer <sean.nyekjaer@prevas.dk>");
+MODULE_DESCRIPTION("Texas Instruments ADS8688 driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/adc/xilinx-xadc-core.c b/drivers/iio/adc/xilinx-xadc-core.c
index 02e636a1c49a..0a6beb3d99cb 100644
--- a/drivers/iio/adc/xilinx-xadc-core.c
+++ b/drivers/iio/adc/xilinx-xadc-core.c
@@ -803,7 +803,7 @@ err:
 	return ret;
 }
 
-static struct iio_buffer_setup_ops xadc_buffer_ops = {
+static const struct iio_buffer_setup_ops xadc_buffer_ops = {
 	.preenable = &xadc_preenable,
 	.postenable = &iio_triggered_buffer_postenable,
 	.predisable = &iio_triggered_buffer_predisable,