Merge tag 'iio-for-v4.2b' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Second set of new driver, functionality and cleanups for IIO in the 4.2 cycle.

Core functionality
* i and q modifiers from quadrature channels.
* IIO_CHAN_INFO_OVERSAMPLING_RATIO added.
* High pass filter attributes added to mirror the existing low pass filter
  ones.

Core cleanups
* Make IIO tools building more cross compiler friendly.
* Substantial rework of the function __iio_update_buffers to greatly simplify
  a hideously evolved function.

New drivers and support
* ACPI0008 ambient light sensor driver. This one has been around a long time to
  will be good to finally get it into mainline.
* Berlin SOC ADC support.
* BMC150 magnetometer.  The accelerometer in the same package has been supported
  for quite some time, so good to have this half as well.
* m62332 DAC driver
* MEMSIC MMC35420 magnetometer.
* ROHM BH1710 and similar ambient light sensors.
* Sensortek STK3310 light sensor.
* Sensortek STK8312 accelerometer.
* Sensortek STK8BA50 accelerometer.
* ti-adc128s052 gains support form the adc122s021 2 channel ADC.

Driver cleanups and functionality.
* Allow various drivers to compile with !GPIOLIB if COMPILE_TEST enabled.
* bmc150 - decouple trigger from buffer to allow other triggers to be used.
* bmg160 - decouple trigger from buffer to allow other triggers to be used.
  Fix a trivial unused field.
* Constify a load of platform_device_id structures.
* inv_mpu6050 - device tree bindings.
* hid-sensors - fix a memory leak during probe if certain errors occur.
* ltr501 - illuminance channel derived (in an non obvious fashion) from the
  intensity channels.
* ltr501 - fix a boundary check on the proximity threshold.
* mlx90614 - drop a pointless return.
* mma8452 - Debugfs register access and fix a bug that had no effect (by
  coincidence)
* ti_am335x_adc - add device tree bindings for sample-delay, open-delay and
  averaging.  The ideal settings for these tend to be board design specific.

6 files changed, 461 insertions, 15 deletions

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index e36a73e7c3a8..7c5565891cb8 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -135,6 +135,13 @@ config AXP288_ADC
 	  device. Depending on platform configuration, this general purpose ADC can
 	  be used for sampling sensors such as thermal resistors.
 
+config BERLIN2_ADC
+	tristate "Marvell Berlin2 ADC driver"
+	depends on ARCH_BERLIN
+	help
+	  Marvell Berlin2 ADC driver. This ADC has 8 channels, with one used for
+	  temperature measurement.
+
 config DA9150_GPADC
 	tristate "Dialog DA9150 GPADC driver support"
 	depends on MFD_DA9150
@@ -285,11 +292,11 @@ config TI_ADC081C
 	  called ti-adc081c.
 
 config TI_ADC128S052
-	tristate "Texas Instruments ADC128S052"
+	tristate "Texas Instruments ADC128S052/ADC122S021"
 	depends on SPI
 	help
 	  If you say yes here you get support for Texas Instruments ADC128S052
-	  chip.
+	  and ADC122S021 chips.
 
 	  This driver can also be built as a module. If so, the module will be
 	  called ti-adc128s052.
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 3930e63e84bc..a0962103e866 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_AD7887) += ad7887.o
 obj-$(CONFIG_AD799X) += ad799x.o
 obj-$(CONFIG_AT91_ADC) += at91_adc.o
 obj-$(CONFIG_AXP288_ADC) += axp288_adc.o
+obj-$(CONFIG_BERLIN2_ADC) += berlin2-adc.o
 obj-$(CONFIG_DA9150_GPADC) += da9150-gpadc.o
 obj-$(CONFIG_CC10001_ADC) += cc10001_adc.o
 obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o
diff --git a/drivers/iio/adc/axp288_adc.c b/drivers/iio/adc/axp288_adc.c
index 56008a86b78f..0c904edd6c00 100644
--- a/drivers/iio/adc/axp288_adc.c
+++ b/drivers/iio/adc/axp288_adc.c
@@ -238,7 +238,7 @@ static int axp288_adc_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static struct platform_device_id axp288_adc_id_table[] = {
+static const struct platform_device_id axp288_adc_id_table[] = {
 	{ .name = "axp288_adc" },
 	{},
 };
diff --git a/drivers/iio/adc/berlin2-adc.c b/drivers/iio/adc/berlin2-adc.c
new file mode 100644
index 000000000000..aecc9ad995ad
--- /dev/null
+++ b/drivers/iio/adc/berlin2-adc.c
@@ -0,0 +1,378 @@
+/*
+ * Marvell Berlin2 ADC driver
+ *
+ * Copyright (C) 2015 Marvell Technology Group Ltd.
+ *
+ * Antoine Tenart <antoine.tenart@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/iio/iio.h>
+#include <linux/iio/driver.h>
+#include <linux/iio/machine.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+
+#define BERLIN2_SM_CTRL				0x14
+#define  BERLIN2_SM_CTRL_SM_SOC_INT		BIT(1)
+#define  BERLIN2_SM_CTRL_SOC_SM_INT		BIT(2)
+#define  BERLIN2_SM_CTRL_ADC_SEL(x)		(BIT(x) << 5)	/* 0-15 */
+#define  BERLIN2_SM_CTRL_ADC_SEL_MASK		(0xf << 5)
+#define  BERLIN2_SM_CTRL_ADC_POWER		BIT(9)
+#define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV2	(0x0 << 10)
+#define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV3	(0x1 << 10)
+#define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV4	(0x2 << 10)
+#define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV8	(0x3 << 10)
+#define  BERLIN2_SM_CTRL_ADC_CLKSEL_MASK	(0x3 << 10)
+#define  BERLIN2_SM_CTRL_ADC_START		BIT(12)
+#define  BERLIN2_SM_CTRL_ADC_RESET		BIT(13)
+#define  BERLIN2_SM_CTRL_ADC_BANDGAP_RDY	BIT(14)
+#define  BERLIN2_SM_CTRL_ADC_CONT_SINGLE	(0x0 << 15)
+#define  BERLIN2_SM_CTRL_ADC_CONT_CONTINUOUS	(0x1 << 15)
+#define  BERLIN2_SM_CTRL_ADC_BUFFER_EN		BIT(16)
+#define  BERLIN2_SM_CTRL_ADC_VREF_EXT		(0x0 << 17)
+#define  BERLIN2_SM_CTRL_ADC_VREF_INT		(0x1 << 17)
+#define  BERLIN2_SM_CTRL_ADC_ROTATE		BIT(19)
+#define  BERLIN2_SM_CTRL_TSEN_EN		BIT(20)
+#define  BERLIN2_SM_CTRL_TSEN_CLK_SEL_125	(0x0 << 21)	/* 1.25 MHz */
+#define  BERLIN2_SM_CTRL_TSEN_CLK_SEL_250	(0x1 << 21)	/* 2.5 MHz */
+#define  BERLIN2_SM_CTRL_TSEN_MODE_0_125	(0x0 << 22)	/* 0-125 C */
+#define  BERLIN2_SM_CTRL_TSEN_MODE_10_50	(0x1 << 22)	/* 10-50 C */
+#define  BERLIN2_SM_CTRL_TSEN_RESET		BIT(29)
+#define BERLIN2_SM_ADC_DATA			0x20
+#define  BERLIN2_SM_ADC_MASK			0x3ff
+#define BERLIN2_SM_ADC_STATUS			0x1c
+#define  BERLIN2_SM_ADC_STATUS_DATA_RDY(x)	BIT(x)		/* 0-15 */
+#define  BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK	0xf
+#define  BERLIN2_SM_ADC_STATUS_INT_EN(x)	(BIT(x) << 16)	/* 0-15 */
+#define  BERLIN2_SM_ADC_STATUS_INT_EN_MASK	(0xf << 16)
+#define BERLIN2_SM_TSEN_STATUS			0x24
+#define  BERLIN2_SM_TSEN_STATUS_DATA_RDY	BIT(0)
+#define  BERLIN2_SM_TSEN_STATUS_INT_EN		BIT(1)
+#define BERLIN2_SM_TSEN_DATA			0x28
+#define  BERLIN2_SM_TSEN_MASK			0xfff
+#define BERLIN2_SM_TSEN_CTRL			0x74
+#define  BERLIN2_SM_TSEN_CTRL_START		BIT(8)
+#define  BERLIN2_SM_TSEN_CTRL_SETTLING_4	(0x0 << 21)	/* 4 us */
+#define  BERLIN2_SM_TSEN_CTRL_SETTLING_12	(0x1 << 21)	/* 12 us */
+#define  BERLIN2_SM_TSEN_CTRL_SETTLING_MASK	(0x1 << 21)
+#define  BERLIN2_SM_TSEN_CTRL_TRIM(x)		((x) << 22)
+#define  BERLIN2_SM_TSEN_CTRL_TRIM_MASK		(0xf << 22)
+
+struct berlin2_adc_priv {
+	struct regmap		*regmap;
+	struct mutex		lock;
+	wait_queue_head_t	wq;
+	bool			data_available;
+	int			data;
+};
+
+#define BERLIN2_ADC_CHANNEL(n, t)					\
+		{							\
+			.channel	= n,				\
+			.datasheet_name	= "channel"#n,			\
+			.type		= t,				\
+			.indexed	= 1,				\
+			.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
+		}
+
+static struct iio_chan_spec berlin2_adc_channels[] = {
+	BERLIN2_ADC_CHANNEL(0, IIO_VOLTAGE),	/* external input */
+	BERLIN2_ADC_CHANNEL(1, IIO_VOLTAGE),	/* external input */
+	BERLIN2_ADC_CHANNEL(2, IIO_VOLTAGE),	/* external input */
+	BERLIN2_ADC_CHANNEL(3, IIO_VOLTAGE),	/* external input */
+	BERLIN2_ADC_CHANNEL(4, IIO_VOLTAGE),	/* reserved */
+	BERLIN2_ADC_CHANNEL(5, IIO_VOLTAGE),	/* reserved */
+	{					/* temperature sensor */
+		.channel		= 6,
+		.datasheet_name		= "channel6",
+		.type			= IIO_TEMP,
+		.indexed		= 0,
+		.info_mask_separate	= BIT(IIO_CHAN_INFO_PROCESSED),
+	},
+	BERLIN2_ADC_CHANNEL(7, IIO_VOLTAGE),	/* reserved */
+	IIO_CHAN_SOFT_TIMESTAMP(8),		/* timestamp */
+};
+#define BERLIN2_N_CHANNELS	ARRAY_SIZE(berlin2_adc_channels)
+
+static int berlin2_adc_read(struct iio_dev *indio_dev, int channel)
+{
+	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
+	int data, ret;
+
+	mutex_lock(&priv->lock);
+
+	/* Configure the ADC */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+			BERLIN2_SM_CTRL_ADC_RESET | BERLIN2_SM_CTRL_ADC_SEL_MASK
+			| BERLIN2_SM_CTRL_ADC_START,
+			BERLIN2_SM_CTRL_ADC_SEL(channel) | BERLIN2_SM_CTRL_ADC_START);
+
+	ret = wait_event_interruptible_timeout(priv->wq, priv->data_available,
+			msecs_to_jiffies(1000));
+
+	/* Disable the interrupts */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_ADC_STATUS,
+			BERLIN2_SM_ADC_STATUS_INT_EN(channel), 0);
+
+	if (ret == 0)
+		ret = -ETIMEDOUT;
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
+
+	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+			BERLIN2_SM_CTRL_ADC_START, 0);
+
+	data = priv->data;
+	priv->data_available = false;
+
+	mutex_unlock(&priv->lock);
+
+	return data;
+}
+
+static int berlin2_adc_tsen_read(struct iio_dev *indio_dev)
+{
+	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
+	int data, ret;
+
+	mutex_lock(&priv->lock);
+
+	/* Configure the ADC */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+			BERLIN2_SM_CTRL_TSEN_RESET | BERLIN2_SM_CTRL_ADC_ROTATE,
+			BERLIN2_SM_CTRL_ADC_ROTATE);
+
+	/* Configure the temperature sensor */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_CTRL,
+			BERLIN2_SM_TSEN_CTRL_TRIM_MASK | BERLIN2_SM_TSEN_CTRL_SETTLING_MASK
+			| BERLIN2_SM_TSEN_CTRL_START,
+			BERLIN2_SM_TSEN_CTRL_TRIM(3) | BERLIN2_SM_TSEN_CTRL_SETTLING_12
+			| BERLIN2_SM_TSEN_CTRL_START);
+
+	ret = wait_event_interruptible_timeout(priv->wq, priv->data_available,
+			msecs_to_jiffies(1000));
+
+	/* Disable interrupts */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_STATUS,
+			BERLIN2_SM_TSEN_STATUS_INT_EN, 0);
+
+	if (ret == 0)
+		ret = -ETIMEDOUT;
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
+
+	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_CTRL,
+			BERLIN2_SM_TSEN_CTRL_START, 0);
+
+	data = priv->data;
+	priv->data_available = false;
+
+	mutex_unlock(&priv->lock);
+
+	return data;
+}
+
+static int berlin2_adc_read_raw(struct iio_dev *indio_dev,
+		struct iio_chan_spec const *chan, int *val, int *val2,
+		long mask)
+{
+	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
+	int temp;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		if (chan->type != IIO_VOLTAGE)
+			return -EINVAL;
+
+		/* Enable the interrupts */
+		regmap_write(priv->regmap, BERLIN2_SM_ADC_STATUS,
+				BERLIN2_SM_ADC_STATUS_INT_EN(chan->channel));
+
+		*val = berlin2_adc_read(indio_dev, chan->channel);
+		if (*val < 0)
+			return *val;
+
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_PROCESSED:
+		if (chan->type != IIO_TEMP)
+			return -EINVAL;
+
+		/* Enable interrupts */
+		regmap_write(priv->regmap, BERLIN2_SM_TSEN_STATUS,
+				BERLIN2_SM_TSEN_STATUS_INT_EN);
+
+		temp = berlin2_adc_tsen_read(indio_dev);
+		if (temp < 0)
+			return temp;
+
+		if (temp > 2047)
+			temp = -(4096 - temp);
+
+		/* Convert to milli Celsius */
+		*val = ((temp * 100000) / 264 - 270000);
+		return IIO_VAL_INT;
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static irqreturn_t berlin2_adc_irq(int irq, void *private)
+{
+	struct berlin2_adc_priv *priv = iio_priv(private);
+	unsigned val;
+
+	regmap_read(priv->regmap, BERLIN2_SM_ADC_STATUS, &val);
+	if (val & BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK) {
+		regmap_read(priv->regmap, BERLIN2_SM_ADC_DATA, &priv->data);
+		priv->data &= BERLIN2_SM_ADC_MASK;
+
+		val &= ~BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK;
+		regmap_write(priv->regmap, BERLIN2_SM_ADC_STATUS, val);
+
+		priv->data_available = true;
+		wake_up_interruptible(&priv->wq);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t berlin2_adc_tsen_irq(int irq, void *private)
+{
+	struct berlin2_adc_priv *priv = iio_priv(private);
+	unsigned val;
+
+	regmap_read(priv->regmap, BERLIN2_SM_TSEN_STATUS, &val);
+	if (val & BERLIN2_SM_TSEN_STATUS_DATA_RDY) {
+		regmap_read(priv->regmap, BERLIN2_SM_TSEN_DATA, &priv->data);
+		priv->data &= BERLIN2_SM_TSEN_MASK;
+
+		val &= ~BERLIN2_SM_TSEN_STATUS_DATA_RDY;
+		regmap_write(priv->regmap, BERLIN2_SM_TSEN_STATUS, val);
+
+		priv->data_available = true;
+		wake_up_interruptible(&priv->wq);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static const struct iio_info berlin2_adc_info = {
+	.driver_module	= THIS_MODULE,
+	.read_raw	= berlin2_adc_read_raw,
+};
+
+static int berlin2_adc_probe(struct platform_device *pdev)
+{
+	struct iio_dev *indio_dev;
+	struct berlin2_adc_priv *priv;
+	struct device_node *parent_np = of_get_parent(pdev->dev.of_node);
+	int irq, tsen_irq;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&pdev->dev,
+					  sizeof(struct berlin2_adc_priv));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	priv = iio_priv(indio_dev);
+	platform_set_drvdata(pdev, indio_dev);
+
+	priv->regmap = syscon_node_to_regmap(parent_np);
+	of_node_put(parent_np);
+	if (IS_ERR(priv->regmap))
+		return PTR_ERR(priv->regmap);
+
+	irq = platform_get_irq_byname(pdev, "adc");
+	if (irq < 0)
+		return -ENODEV;
+
+	tsen_irq = platform_get_irq_byname(pdev, "tsen");
+	if (tsen_irq < 0)
+		return -ENODEV;
+
+	ret = devm_request_irq(&pdev->dev, irq, berlin2_adc_irq, 0,
+			pdev->dev.driver->name, indio_dev);
+	if (ret)
+		return ret;
+
+	ret = devm_request_irq(&pdev->dev, tsen_irq, berlin2_adc_tsen_irq,
+			0, pdev->dev.driver->name, indio_dev);
+	if (ret)
+		return ret;
+
+	init_waitqueue_head(&priv->wq);
+	mutex_init(&priv->lock);
+
+	indio_dev->dev.parent = &pdev->dev;
+	indio_dev->name = dev_name(&pdev->dev);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &berlin2_adc_info;
+
+	indio_dev->num_channels = BERLIN2_N_CHANNELS;
+	indio_dev->channels = berlin2_adc_channels;
+
+	/* Power up the ADC */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+			BERLIN2_SM_CTRL_ADC_POWER, BERLIN2_SM_CTRL_ADC_POWER);
+
+	ret = iio_device_register(indio_dev);
+	if (ret) {
+		/* Power down the ADC */
+		regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+				BERLIN2_SM_CTRL_ADC_POWER, 0);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int berlin2_adc_remove(struct platform_device *pdev)
+{
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+
+	/* Power down the ADC */
+	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
+			BERLIN2_SM_CTRL_ADC_POWER, 0);
+
+	return 0;
+}
+
+static const struct of_device_id berlin2_adc_match[] = {
+	{ .compatible = "marvell,berlin2-adc", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, berlin2_adc_match);
+
+static struct platform_driver berlin2_adc_driver = {
+	.driver	= {
+		.name		= "berlin2-adc",
+		.of_match_table	= berlin2_adc_match,
+	},
+	.probe	= berlin2_adc_probe,
+	.remove	= berlin2_adc_remove,
+};
+module_platform_driver(berlin2_adc_driver);
+
+MODULE_AUTHOR("Antoine Tenart <antoine.tenart@free-electrons.com>");
+MODULE_DESCRIPTION("Marvell Berlin2 ADC driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/adc/ti-adc128s052.c b/drivers/iio/adc/ti-adc128s052.c
index 655cb564ec54..915be6b60097 100644
--- a/drivers/iio/adc/ti-adc128s052.c
+++ b/drivers/iio/adc/ti-adc128s052.c
@@ -1,9 +1,10 @@
 /*
  * Copyright (C) 2014 Angelo Compagnucci <angelo.compagnucci@gmail.com>
  *
- * Driver for Texas Instruments' ADC128S052 ADC chip.
- * Datasheet can be found here:
+ * Driver for Texas Instruments' ADC128S052 and ADC122S021 ADC chip.
+ * Datasheets can be found here:
  * http://www.ti.com/lit/ds/symlink/adc128s052.pdf
+ * http://www.ti.com/lit/ds/symlink/adc122s021.pdf
  *
  * 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
@@ -16,6 +17,11 @@
 #include <linux/iio/iio.h>
 #include <linux/regulator/consumer.h>
 
+struct adc128_configuration {
+	const struct iio_chan_spec	*channels;
+	u8				num_channels;
+};
+
 struct adc128 {
 	struct spi_device *spi;
 
@@ -92,7 +98,7 @@ static int adc128_read_raw(struct iio_dev *indio_dev,
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \
 	}
 
-static const struct iio_chan_spec adc128_channels[] = {
+static const struct iio_chan_spec adc128s052_channels[] = {
 	ADC128_VOLTAGE_CHANNEL(0),
 	ADC128_VOLTAGE_CHANNEL(1),
 	ADC128_VOLTAGE_CHANNEL(2),
@@ -103,6 +109,16 @@ static const struct iio_chan_spec adc128_channels[] = {
 	ADC128_VOLTAGE_CHANNEL(7),
 };
 
+static const struct iio_chan_spec adc122s021_channels[] = {
+	ADC128_VOLTAGE_CHANNEL(0),
+	ADC128_VOLTAGE_CHANNEL(1),
+};
+
+static const struct adc128_configuration adc128_config[] = {
+	{ adc128s052_channels, ARRAY_SIZE(adc128s052_channels) },
+	{ adc122s021_channels, ARRAY_SIZE(adc122s021_channels) },
+};
+
 static const struct iio_info adc128_info = {
 	.read_raw = adc128_read_raw,
 	.driver_module = THIS_MODULE,
@@ -112,6 +128,7 @@ static int adc128_probe(struct spi_device *spi)
 {
 	struct iio_dev *indio_dev;
 	struct adc128 *adc;
+	int config = spi_get_device_id(spi)->driver_data;
 	int ret;
 
 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc));
@@ -128,8 +145,8 @@ static int adc128_probe(struct spi_device *spi)
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &adc128_info;
 
-	indio_dev->channels = adc128_channels;
-	indio_dev->num_channels = ARRAY_SIZE(adc128_channels);
+	indio_dev->channels = adc128_config[config].channels;
+	indio_dev->num_channels = adc128_config[config].num_channels;
 
 	adc->reg = devm_regulator_get(&spi->dev, "vref");
 	if (IS_ERR(adc->reg))
@@ -158,7 +175,8 @@ static int adc128_remove(struct spi_device *spi)
 }
 
 static const struct spi_device_id adc128_id[] = {
-	{ "adc128s052", 0},
+	{ "adc128s052", 0},	/* index into adc128_config */
+	{ "adc122s021",	1},
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, adc128_id);
diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index 42e444044ea5..942320e32753 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -37,6 +37,7 @@ struct tiadc_device {
 	u8 channel_step[8];
 	int buffer_en_ch_steps;
 	u16 data[8];
+	u32 open_delay[8], sample_delay[8], step_avg[8];
 };
 
 static unsigned int tiadc_readl(struct tiadc_device *adc, unsigned int reg)
@@ -85,6 +86,7 @@ static u32 get_adc_step_bit(struct tiadc_device *adc_dev, int chan)
 static void tiadc_step_config(struct iio_dev *indio_dev)
 {
 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
+	struct device *dev = adc_dev->mfd_tscadc->dev;
 	unsigned int stepconfig;
 	int i, steps = 0;
 
@@ -98,20 +100,47 @@ static void tiadc_step_config(struct iio_dev *indio_dev)
 	 * needs to be given to ADC to digitalize data.
 	 */
 
-	if (iio_buffer_enabled(indio_dev))
-		stepconfig = STEPCONFIG_AVG_16 | STEPCONFIG_FIFO1
-					| STEPCONFIG_MODE_SWCNT;
-	else
-		stepconfig = STEPCONFIG_AVG_16 | STEPCONFIG_FIFO1;
 
 	for (i = 0; i < adc_dev->channels; i++) {
 		int chan;
 
 		chan = adc_dev->channel_line[i];
+
+		if (adc_dev->step_avg[i] > STEPCONFIG_AVG_16) {
+			dev_warn(dev, "chan %d step_avg truncating to %d\n",
+				 chan, STEPCONFIG_AVG_16);
+			adc_dev->step_avg[i] = STEPCONFIG_AVG_16;
+		}
+
+		if (adc_dev->step_avg[i])
+			stepconfig =
+			STEPCONFIG_AVG(ffs(adc_dev->step_avg[i]) - 1) |
+			STEPCONFIG_FIFO1;
+		else
+			stepconfig = STEPCONFIG_FIFO1;
+
+		if (iio_buffer_enabled(indio_dev))
+			stepconfig |= STEPCONFIG_MODE_SWCNT;
+
 		tiadc_writel(adc_dev, REG_STEPCONFIG(steps),
 				stepconfig | STEPCONFIG_INP(chan));
+
+		if (adc_dev->open_delay[i] > STEPDELAY_OPEN_MASK) {
+			dev_warn(dev, "chan %d open delay truncating to 0x3FFFF\n",
+				 chan);
+			adc_dev->open_delay[i] = STEPDELAY_OPEN_MASK;
+		}
+
+		if (adc_dev->sample_delay[i] > 0xFF) {
+			dev_warn(dev, "chan %d sample delay truncating to 0xFF\n",
+				 chan);
+			adc_dev->sample_delay[i] = 0xFF;
+		}
+
 		tiadc_writel(adc_dev, REG_STEPDELAY(steps),
-				STEPCONFIG_OPENDLY);
+				STEPDELAY_OPEN(adc_dev->open_delay[i]) |
+				STEPDELAY_SAMPLE(adc_dev->sample_delay[i]));
+
 		adc_dev->channel_step[i] = steps;
 		steps++;
 	}
@@ -406,9 +435,22 @@ static int tiadc_parse_dt(struct platform_device *pdev,
 
 	of_property_for_each_u32(node, "ti,adc-channels", prop, cur, val) {
 		adc_dev->channel_line[channels] = val;
+
+		/* Set Default values for optional DT parameters */
+		adc_dev->open_delay[channels] = STEPCONFIG_OPENDLY;
+		adc_dev->sample_delay[channels] = STEPCONFIG_SAMPLEDLY;
+		adc_dev->step_avg[channels] = 16;
+
 		channels++;
 	}
 
+	of_property_read_u32_array(node, "ti,chan-step-avg",
+				   adc_dev->step_avg, channels);
+	of_property_read_u32_array(node, "ti,chan-step-opendelay",
+				   adc_dev->open_delay, channels);
+	of_property_read_u32_array(node, "ti,chan-step-sampledelay",
+				   adc_dev->sample_delay, channels);
+
 	adc_dev->channels = channels;
 	return 0;
 }