Merge tag 'iio-for-3.13a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

First round of new drivers, functionality and cleanups for IIO in the 3.13 cycle

A number of new drivers and some new functionality + a lot of cleanups
all over IIO.

New Core Elements

1) New INT_TIME info_mask element for integration time, which may have
   different effects on measurement noise and similar, than an amplifier
   and hence is different from existing SCALE.  Already existed in some
   drivers as a custom attribute.

2) Introduce a iio_push_buffers_with_timestamp helper to cover the common
   case of filling the last 64 bits of data to be passed to the buffer with
   a timestamp.  Applied to lots of drivers. Cuts down on repeated code and
   moves a slightly fiddly bit of logic into a single location.

3) Introduce info_mask_[shared_by_dir/shared_by_all] elements to allow support
   of elements such as sampling_frequency which is typically shared by all
   input channels on a device.  This reduces code and makes these controls
   available from in kernel consumers of IIO devices.

New drivers

1) MCP3422/3/4 ADC

2) TSL4531 ambient light sensor

3) TCS3472/5 color light sensor

4) GP2AP020A00F ambient light / proximity sensor

5) LPS001WP support added to ST pressure sensor driver.

New driver functionality

1) ti_am335x_adc Add buffered sampling support.
   This device has a hardware fifo that is fed directly into an IIO kfifo
   buffer based on a watershed interrupt.  Note this will act as an example
   of how to handle this increasingly common type of device.
   The only previous example - sca3000 - take a less than optimal approach
   which is largely why it is still in staging.
   A couple of little cleanups for that new functionality followed later.

Core cleanups:

1) MAINTAINERS - Sachin actually brought my email address up to date because
   I said I'd do it and never got around to it :)

2) Assign buffer list elements as single element lists to simplify the
   iio_buffer_is_active logic.

3) wake_up_interruptible_poll instead of wake_up_interruptible to only wake
   up threads waiting for poll notifications.

4) Add O_CLOEXEC flag to anon_inode_get_fd call for IIO event interface.

5) Change iio_push_to_buffers to take a void * pointer so as to avoid some
   annoying and unnecessary type casts.

6) iio_compute_scan_bytes incorrectly took a long rather than unsigned long.

7) Various minor tidy ups.

Driver cleanups (in no particular order)

1) Another set of devm_ allocations patches from Sachin Kamat.

2) tsl2x7x - 0 to NULL cleanup.

3) hmc5843 - fix missing > in MODULE_AUTHOR

4) Set of strict_strto* to kstrto* conversions.

5) mxs-lradc - fix ordering of resource removal to match creation

6) mxs-lradc - add MODULE_ALIAS

7) adc7606 - drop a work pending test duplicated in core functions.

8) hmc5843 - devm_ allocation patch

9) Series of redundant breaks removed.

10) ad2s1200 - pr_err -> dev_err

11) adjd_s311 - use INT_TIME

12)  ST sensors - large set of cleanups from Lee Jones and removed restriction
    to using only triggers provided by the st_sensors themselves from
    Dennis Ciocca.

13) dummy and tmp006 provide sampling_frequency via info_mask_shared_by_all.

14) tcs3472 - fix incorrect buffer size and wrong device pointer used in
    suspend / resume functions.

15) max1363 - use defaults for buffer setup ops as provided by the triggered
    buffer helpers as they are the same as were specified in max1363 driver.

16) Trivial tidy ups in a number of other drivers.

12 files changed, 646 insertions, 81 deletions

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 09371cb..8b88518 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -145,6 +145,16 @@ config MCP320X
 	  This driver can also be built as a module. If so, the module will be
 	  called mcp320x.
 
+config MCP3422
+	tristate "Microchip Technology MCP3422/3/4 driver"
+	depends on I2C
+	help
+	  Say yes here to build support for Microchip Technology's MCP3422,
+	  MCP3423 or MCP3424 analog to digital converters.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called mcp3422.
+
 config NAU7802
 	tristate "Nuvoton NAU7802 ADC driver"
 	depends on I2C
@@ -167,6 +177,7 @@ config TI_ADC081C
 config TI_AM335X_ADC
 	tristate "TI's AM335X ADC driver"
 	depends on MFD_TI_AM335X_TSCADC
+	select IIO_KFIFO_BUF
 	help
 	  Say yes here to build support for Texas Instruments ADC
 	  driver which is also a MFD client.
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 33656ef..ba9a10a 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o
 obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
 obj-$(CONFIG_MAX1363) += max1363.o
 obj-$(CONFIG_MCP320X) += mcp320x.o
+obj-$(CONFIG_MCP3422) += mcp3422.o
 obj-$(CONFIG_NAU7802) += nau7802.o
 obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
 obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
diff --git a/drivers/iio/adc/ad7266.c b/drivers/iio/adc/ad7266.c
index 371731d..656aa3e 100644
--- a/drivers/iio/adc/ad7266.c
+++ b/drivers/iio/adc/ad7266.c
@@ -96,9 +96,8 @@ static irqreturn_t ad7266_trigger_handler(int irq, void *p)
 
 	ret = spi_read(st->spi, st->data, 4);
 	if (ret == 0) {
-		if (indio_dev->scan_timestamp)
-			((s64 *)st->data)[1] = pf->timestamp;
-		iio_push_to_buffers(indio_dev, (u8 *)st->data);
+		iio_push_to_buffers_with_timestamp(indio_dev, st->data,
+			    pf->timestamp);
 	}
 
 	iio_trigger_notify_done(indio_dev->trig);
@@ -293,7 +292,7 @@ static const struct iio_info ad7266_info = {
 	.driver_module = THIS_MODULE,
 };
 
-static unsigned long ad7266_available_scan_masks[] = {
+static const unsigned long ad7266_available_scan_masks[] = {
 	0x003,
 	0x00c,
 	0x030,
@@ -303,14 +302,14 @@ static unsigned long ad7266_available_scan_masks[] = {
 	0x000,
 };
 
-static unsigned long ad7266_available_scan_masks_diff[] = {
+static const unsigned long ad7266_available_scan_masks_diff[] = {
 	0x003,
 	0x00c,
 	0x030,
 	0x000,
 };
 
-static unsigned long ad7266_available_scan_masks_fixed[] = {
+static const unsigned long ad7266_available_scan_masks_fixed[] = {
 	0x003,
 	0x000,
 };
@@ -318,7 +317,7 @@ static unsigned long ad7266_available_scan_masks_fixed[] = {
 struct ad7266_chan_info {
 	const struct iio_chan_spec *channels;
 	unsigned int num_channels;
-	unsigned long *scan_masks;
+	const unsigned long *scan_masks;
 };
 
 #define AD7266_CHAN_INFO_INDEX(_differential, _signed, _fixed) \
diff --git a/drivers/iio/adc/ad7298.c b/drivers/iio/adc/ad7298.c
index 85d1481..2a3b65c 100644
--- a/drivers/iio/adc/ad7298.c
+++ b/drivers/iio/adc/ad7298.c
@@ -159,20 +159,14 @@ static irqreturn_t ad7298_trigger_handler(int irq, void *p)
 	struct iio_poll_func *pf = p;
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct ad7298_state *st = iio_priv(indio_dev);
-	s64 time_ns = 0;
 	int b_sent;
 
 	b_sent = spi_sync(st->spi, &st->ring_msg);
 	if (b_sent)
 		goto done;
 
-	if (indio_dev->scan_timestamp) {
-		time_ns = iio_get_time_ns();
-		memcpy((u8 *)st->rx_buf + indio_dev->scan_bytes - sizeof(s64),
-			&time_ns, sizeof(time_ns));
-	}
-
-	iio_push_to_buffers(indio_dev, (u8 *)st->rx_buf);
+	iio_push_to_buffers_with_timestamp(indio_dev, st->rx_buf,
+		iio_get_time_ns());
 
 done:
 	iio_trigger_notify_done(indio_dev->trig);
diff --git a/drivers/iio/adc/ad7476.c b/drivers/iio/adc/ad7476.c
index 6d2b1d8..8d808b9 100644
--- a/drivers/iio/adc/ad7476.c
+++ b/drivers/iio/adc/ad7476.c
@@ -64,19 +64,14 @@ static irqreturn_t ad7476_trigger_handler(int irq, void  *p)
 	struct iio_poll_func *pf = p;
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct ad7476_state *st = iio_priv(indio_dev);
-	s64 time_ns;
 	int b_sent;
 
 	b_sent = spi_sync(st->spi, &st->msg);
 	if (b_sent < 0)
 		goto done;
 
-	time_ns = iio_get_time_ns();
-
-	if (indio_dev->scan_timestamp)
-		((s64 *)st->data)[1] = time_ns;
-
-	iio_push_to_buffers(indio_dev, st->data);
+	iio_push_to_buffers_with_timestamp(indio_dev, st->data,
+		iio_get_time_ns());
 done:
 	iio_trigger_notify_done(indio_dev->trig);
 
diff --git a/drivers/iio/adc/ad7887.c b/drivers/iio/adc/ad7887.c
index 9dd077b..faedd0e 100644
--- a/drivers/iio/adc/ad7887.c
+++ b/drivers/iio/adc/ad7887.c
@@ -121,20 +121,14 @@ static irqreturn_t ad7887_trigger_handler(int irq, void *p)
 	struct iio_poll_func *pf = p;
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct ad7887_state *st = iio_priv(indio_dev);
-	s64 time_ns;
 	int b_sent;
 
 	b_sent = spi_sync(st->spi, st->ring_msg);
 	if (b_sent)
 		goto done;
 
-	time_ns = iio_get_time_ns();
-
-	if (indio_dev->scan_timestamp)
-		memcpy(st->data + indio_dev->scan_bytes - sizeof(s64),
-		       &time_ns, sizeof(time_ns));
-
-	iio_push_to_buffers(indio_dev, st->data);
+	iio_push_to_buffers_with_timestamp(indio_dev, st->data,
+		iio_get_time_ns());
 done:
 	iio_trigger_notify_done(indio_dev->trig);
 
diff --git a/drivers/iio/adc/ad7923.c b/drivers/iio/adc/ad7923.c
index 4108dbb..28732c2 100644
--- a/drivers/iio/adc/ad7923.c
+++ b/drivers/iio/adc/ad7923.c
@@ -174,20 +174,14 @@ static irqreturn_t ad7923_trigger_handler(int irq, void *p)
 	struct iio_poll_func *pf = p;
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct ad7923_state *st = iio_priv(indio_dev);
-	s64 time_ns = 0;
 	int b_sent;
 
 	b_sent = spi_sync(st->spi, &st->ring_msg);
 	if (b_sent)
 		goto done;
 
-	if (indio_dev->scan_timestamp) {
-		time_ns = iio_get_time_ns();
-		memcpy((u8 *)st->rx_buf + indio_dev->scan_bytes - sizeof(s64),
-			&time_ns, sizeof(time_ns));
-	}
-
-	iio_push_to_buffers(indio_dev, (u8 *)st->rx_buf);
+	iio_push_to_buffers_with_timestamp(indio_dev, st->rx_buf,
+		iio_get_time_ns());
 
 done:
 	iio_trigger_notify_done(indio_dev->trig);
diff --git a/drivers/iio/adc/ad_sigma_delta.c b/drivers/iio/adc/ad_sigma_delta.c
index f0d6335..2b59112 100644
--- a/drivers/iio/adc/ad_sigma_delta.c
+++ b/drivers/iio/adc/ad_sigma_delta.c
@@ -368,10 +368,6 @@ static irqreturn_t ad_sd_trigger_handler(int irq, void *p)
 
 	memset(data, 0x00, 16);
 
-	/* Guaranteed to be aligned with 8 byte boundary */
-	if (indio_dev->scan_timestamp)
-		((s64 *)data)[1] = pf->timestamp;
-
 	reg_size = indio_dev->channels[0].scan_type.realbits +
 			indio_dev->channels[0].scan_type.shift;
 	reg_size = DIV_ROUND_UP(reg_size, 8);
@@ -391,7 +387,7 @@ static irqreturn_t ad_sd_trigger_handler(int irq, void *p)
 		break;
 	}
 
-	iio_push_to_buffers(indio_dev, (uint8_t *)data);
+	iio_push_to_buffers_with_timestamp(indio_dev, data, pf->timestamp);
 
 	iio_trigger_notify_done(indio_dev->trig);
 	sigma_delta->irq_dis = false;
diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index 84be63b..5c8f690 100644
--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -83,13 +83,7 @@ static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
 		j++;
 	}
 
-	if (idev->scan_timestamp) {
-		s64 *timestamp = (s64 *)((u8 *)st->buffer +
-					ALIGN(j, sizeof(s64)));
-		*timestamp = pf->timestamp;
-	}
-
-	iio_push_to_buffers(idev, (u8 *)st->buffer);
+	iio_push_to_buffers_with_timestamp(idev, st->buffer, pf->timestamp);
 
 	iio_trigger_notify_done(idev->trig);
 
@@ -279,7 +273,7 @@ static int at91_adc_trigger_init(struct iio_dev *idev)
 	int i, ret;
 
 	st->trig = devm_kzalloc(&idev->dev,
-				st->trigger_number * sizeof(st->trig),
+				st->trigger_number * sizeof(*st->trig),
 				GFP_KERNEL);
 
 	if (st->trig == NULL) {
diff --git a/drivers/iio/adc/max1363.c b/drivers/iio/adc/max1363.c
index 4fb35d1..b4bc166 100644
--- a/drivers/iio/adc/max1363.c
+++ b/drivers/iio/adc/max1363.c
@@ -1436,7 +1436,6 @@ static irqreturn_t max1363_trigger_handler(int irq, void *p)
 	struct iio_poll_func *pf = p;
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct max1363_state *st = iio_priv(indio_dev);
-	s64 time_ns;
 	__u8 *rxbuf;
 	int b_sent;
 	size_t d_size;
@@ -1470,11 +1469,7 @@ static irqreturn_t max1363_trigger_handler(int irq, void *p)
 	if (b_sent < 0)
 		goto done_free;
 
-	time_ns = iio_get_time_ns();
-
-	if (indio_dev->scan_timestamp)
-		memcpy(rxbuf + d_size - sizeof(s64), &time_ns, sizeof(time_ns));
-	iio_push_to_buffers(indio_dev, rxbuf);
+	iio_push_to_buffers_with_timestamp(indio_dev, rxbuf, iio_get_time_ns());
 
 done_free:
 	kfree(rxbuf);
@@ -1484,12 +1479,6 @@ done:
 	return IRQ_HANDLED;
 }
 
-static const struct iio_buffer_setup_ops max1363_buffered_setup_ops = {
-	.postenable = &iio_triggered_buffer_postenable,
-	.preenable = &iio_sw_buffer_preenable,
-	.predisable = &iio_triggered_buffer_predisable,
-};
-
 static int max1363_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
@@ -1559,7 +1548,7 @@ static int max1363_probe(struct i2c_client *client,
 		goto error_disable_reg;
 
 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
-		&max1363_trigger_handler, &max1363_buffered_setup_ops);
+		&max1363_trigger_handler, NULL);
 	if (ret)
 		goto error_disable_reg;
 
diff --git a/drivers/iio/adc/mcp3422.c b/drivers/iio/adc/mcp3422.c
new file mode 100644
index 0000000..bc93f53
--- /dev/null
+++ b/drivers/iio/adc/mcp3422.c
@@ -0,0 +1,409 @@
+/*
+ * mcp3422.c - driver for the Microchip mcp3422/3/4 chip family
+ *
+ * Copyright (C) 2013, Angelo Compagnucci
+ * Author: Angelo Compagnucci <angelo.compagnucci@gmail.com>
+ *
+ * Datasheet: http://ww1.microchip.com/downloads/en/devicedoc/22088b.pdf
+ *
+ * This driver exports the value of analog input voltage to sysfs, the
+ * voltage unit is nV.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/sysfs.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+/* Masks */
+#define MCP3422_CHANNEL_MASK	0x60
+#define MCP3422_PGA_MASK	0x03
+#define MCP3422_SRATE_MASK	0x0C
+#define MCP3422_SRATE_240	0x0
+#define MCP3422_SRATE_60	0x1
+#define MCP3422_SRATE_15	0x2
+#define MCP3422_SRATE_3	0x3
+#define MCP3422_PGA_1	0
+#define MCP3422_PGA_2	1
+#define MCP3422_PGA_4	2
+#define MCP3422_PGA_8	3
+#define MCP3422_CONT_SAMPLING	0x10
+
+#define MCP3422_CHANNEL(config)	(((config) & MCP3422_CHANNEL_MASK) >> 5)
+#define MCP3422_PGA(config)	((config) & MCP3422_PGA_MASK)
+#define MCP3422_SAMPLE_RATE(config)	(((config) & MCP3422_SRATE_MASK) >> 2)
+
+#define MCP3422_CHANNEL_VALUE(value) (((value) << 5) & MCP3422_CHANNEL_MASK)
+#define MCP3422_PGA_VALUE(value) ((value) & MCP3422_PGA_MASK)
+#define MCP3422_SAMPLE_RATE_VALUE(value) ((value << 2) & MCP3422_SRATE_MASK)
+
+#define MCP3422_CHAN(_index) \
+	{ \
+		.type = IIO_VOLTAGE, \
+		.indexed = 1, \
+		.channel = _index, \
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \
+				| BIT(IIO_CHAN_INFO_SCALE), \
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+	}
+
+/* LSB is in nV to eliminate floating point */
+static const u32 rates_to_lsb[] = {1000000, 250000, 62500, 15625};
+
+/*
+ *  scales calculated as:
+ *  rates_to_lsb[sample_rate] / (1 << pga);
+ *  pga is 1 for 0, 2
+ */
+
+static const int mcp3422_scales[4][4] = {
+	{ 1000000, 250000, 62500, 15625 },
+	{ 500000 , 125000, 31250, 7812 },
+	{ 250000 , 62500 , 15625, 3906 },
+	{ 125000 , 31250 , 7812 , 1953 } };
+
+/* Constant msleep times for data acquisitions */
+static const int mcp3422_read_times[4] = {
+	[MCP3422_SRATE_240] = 1000 / 240,
+	[MCP3422_SRATE_60] = 1000 / 60,
+	[MCP3422_SRATE_15] = 1000 / 15,
+	[MCP3422_SRATE_3] = 1000 / 3 };
+
+/* sample rates to integer conversion table */
+static const int mcp3422_sample_rates[4] = {
+	[MCP3422_SRATE_240] = 240,
+	[MCP3422_SRATE_60] = 60,
+	[MCP3422_SRATE_15] = 15,
+	[MCP3422_SRATE_3] = 3 };
+
+/* sample rates to sign extension table */
+static const int mcp3422_sign_extend[4] = {
+	[MCP3422_SRATE_240] = 12,
+	[MCP3422_SRATE_60] = 14,
+	[MCP3422_SRATE_15] = 16,
+	[MCP3422_SRATE_3] = 18 };
+
+/* Client data (each client gets its own) */
+struct mcp3422 {
+	struct i2c_client *i2c;
+	u8 config;
+	u8 pga[4];
+	struct mutex lock;
+};
+
+static int mcp3422_update_config(struct mcp3422 *adc, u8 newconfig)
+{
+	int ret;
+
+	mutex_lock(&adc->lock);
+
+	ret = i2c_master_send(adc->i2c, &newconfig, 1);
+	if (ret > 0) {
+		adc->config = newconfig;
+		ret = 0;
+	}
+
+	mutex_unlock(&adc->lock);
+
+	return ret;
+}
+
+static int mcp3422_read(struct mcp3422 *adc, int *value, u8 *config)
+{
+	int ret = 0;
+	u8 sample_rate = MCP3422_SAMPLE_RATE(adc->config);
+	u8 buf[4] = {0, 0, 0, 0};
+	u32 temp;
+
+	if (sample_rate == MCP3422_SRATE_3) {
+		ret = i2c_master_recv(adc->i2c, buf, 4);
+		temp = buf[0] << 16 | buf[1] << 8 | buf[2];
+		*config = buf[3];
+	} else {
+		ret = i2c_master_recv(adc->i2c, buf, 3);
+		temp = buf[0] << 8 | buf[1];
+		*config = buf[2];
+	}
+
+	*value = sign_extend32(temp, mcp3422_sign_extend[sample_rate]);
+
+	return ret;
+}
+
+static int mcp3422_read_channel(struct mcp3422 *adc,
+				struct iio_chan_spec const *channel, int *value)
+{
+	int ret;
+	u8 config;
+	u8 req_channel = channel->channel;
+
+	if (req_channel != MCP3422_CHANNEL(adc->config)) {
+		config = adc->config;
+		config &= ~MCP3422_CHANNEL_MASK;
+		config |= MCP3422_CHANNEL_VALUE(req_channel);
+		config &= ~MCP3422_PGA_MASK;
+		config |= MCP3422_PGA_VALUE(adc->pga[req_channel]);
+		ret = mcp3422_update_config(adc, config);
+		if (ret < 0)
+			return ret;
+		msleep(mcp3422_read_times[MCP3422_SAMPLE_RATE(adc->config)]);
+	}
+
+	return mcp3422_read(adc, value, &config);
+}
+
+static int mcp3422_read_raw(struct iio_dev *iio,
+			struct iio_chan_spec const *channel, int *val1,
+			int *val2, long mask)
+{
+	struct mcp3422 *adc = iio_priv(iio);
+	int err;
+
+	u8 sample_rate = MCP3422_SAMPLE_RATE(adc->config);
+	u8 pga		 = MCP3422_PGA(adc->config);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		err = mcp3422_read_channel(adc, channel, val1);
+		if (err < 0)
+			return -EINVAL;
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+
+		*val1 = 0;
+		*val2 = mcp3422_scales[sample_rate][pga];
+		return IIO_VAL_INT_PLUS_NANO;
+
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val1 = mcp3422_sample_rates[MCP3422_SAMPLE_RATE(adc->config)];
+		return IIO_VAL_INT;
+
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int mcp3422_write_raw(struct iio_dev *iio,
+			struct iio_chan_spec const *channel, int val1,
+			int val2, long mask)
+{
+	struct mcp3422 *adc = iio_priv(iio);
+	u8 temp;
+	u8 config = adc->config;
+	u8 req_channel = channel->channel;
+	u8 sample_rate = MCP3422_SAMPLE_RATE(config);
+	u8 i;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		if (val1 != 0)
+			return -EINVAL;
+
+		for (i = 0; i < ARRAY_SIZE(mcp3422_scales[0]); i++) {
+			if (val2 == mcp3422_scales[sample_rate][i]) {
+				adc->pga[req_channel] = i;
+
+				config &= ~MCP3422_CHANNEL_MASK;
+				config |= MCP3422_CHANNEL_VALUE(req_channel);
+				config &= ~MCP3422_PGA_MASK;
+				config |= MCP3422_PGA_VALUE(adc->pga[req_channel]);
+
+				return mcp3422_update_config(adc, config);
+			}
+		}
+		return -EINVAL;
+
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		switch (val1) {
+		case 240:
+			temp = MCP3422_SRATE_240;
+			break;
+		case 60:
+			temp = MCP3422_SRATE_60;
+			break;
+		case 15:
+			temp = MCP3422_SRATE_15;
+			break;
+		case 3:
+			temp = MCP3422_SRATE_3;
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		config &= ~MCP3422_CHANNEL_MASK;
+		config |= MCP3422_CHANNEL_VALUE(req_channel);
+		config &= ~MCP3422_SRATE_MASK;
+		config |= MCP3422_SAMPLE_RATE_VALUE(temp);
+
+		return mcp3422_update_config(adc, config);
+
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int mcp3422_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_SAMP_FREQ:
+		return IIO_VAL_INT_PLUS_MICRO;
+	default:
+		return -EINVAL;
+	}
+}
+
+static ssize_t mcp3422_show_scales(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct mcp3422 *adc = iio_priv(dev_to_iio_dev(dev));
+	u8 sample_rate = MCP3422_SAMPLE_RATE(adc->config);
+
+	return sprintf(buf, "0.%09u 0.%09u 0.%09u 0.%09u\n",
+		mcp3422_scales[sample_rate][0],
+		mcp3422_scales[sample_rate][1],
+		mcp3422_scales[sample_rate][2],
+		mcp3422_scales[sample_rate][3]);
+}
+
+static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("240 60 15 3");
+static IIO_DEVICE_ATTR(in_voltage_scale_available, S_IRUGO,
+		mcp3422_show_scales, NULL, 0);
+
+static struct attribute *mcp3422_attributes[] = {
+	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage_scale_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group mcp3422_attribute_group = {
+	.attrs = mcp3422_attributes,
+};
+
+static const struct iio_chan_spec mcp3422_channels[] = {
+	MCP3422_CHAN(0),
+	MCP3422_CHAN(1),
+};
+
+static const struct iio_chan_spec mcp3424_channels[] = {
+	MCP3422_CHAN(0),
+	MCP3422_CHAN(1),
+	MCP3422_CHAN(2),
+	MCP3422_CHAN(3),
+};
+
+static const struct iio_info mcp3422_info = {
+	.read_raw = mcp3422_read_raw,
+	.write_raw = mcp3422_write_raw,
+	.write_raw_get_fmt = mcp3422_write_raw_get_fmt,
+	.attrs = &mcp3422_attribute_group,
+	.driver_module = THIS_MODULE,
+};
+
+static int mcp3422_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct iio_dev *indio_dev;
+	struct mcp3422 *adc;
+	int err;
+	u8 config;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+		return -ENODEV;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*adc));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	adc = iio_priv(indio_dev);
+	adc->i2c = client;
+
+	mutex_init(&adc->lock);
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->name = dev_name(&client->dev);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &mcp3422_info;
+
+	switch ((unsigned int)(id->driver_data)) {
+	case 2:
+	case 3:
+		indio_dev->channels = mcp3422_channels;
+		indio_dev->num_channels = ARRAY_SIZE(mcp3422_channels);
+		break;
+	case 4:
+		indio_dev->channels = mcp3424_channels;
+		indio_dev->num_channels = ARRAY_SIZE(mcp3424_channels);
+		break;
+	}
+
+	/* meaningful default configuration */
+	config = (MCP3422_CONT_SAMPLING
+		| MCP3422_CHANNEL_VALUE(1)
+		| MCP3422_PGA_VALUE(MCP3422_PGA_1)
+		| MCP3422_SAMPLE_RATE_VALUE(MCP3422_SRATE_240));
+	mcp3422_update_config(adc, config);
+
+	err = iio_device_register(indio_dev);
+	if (err < 0)
+		return err;
+
+	i2c_set_clientdata(client, indio_dev);
+
+	return 0;
+}
+
+static int mcp3422_remove(struct i2c_client *client)
+{
+	iio_device_unregister(i2c_get_clientdata(client));
+	return 0;
+}
+
+static const struct i2c_device_id mcp3422_id[] = {
+	{ "mcp3422", 2 },
+	{ "mcp3423", 3 },
+	{ "mcp3424", 4 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, mcp3422_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id mcp3422_of_match[] = {
+	{ .compatible = "mcp3422" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, mcp3422_of_match);
+#endif
+
+static struct i2c_driver mcp3422_driver = {
+	.driver = {
+		.name = "mcp3422",
+		.owner = THIS_MODULE,
+		.of_match_table = of_match_ptr(mcp3422_of_match),
+	},
+	.probe = mcp3422_probe,
+	.remove = mcp3422_remove,
+	.id_table = mcp3422_id,
+};
+module_i2c_driver(mcp3422_driver);
+
+MODULE_AUTHOR("Angelo Compagnucci <angelo.compagnucci@gmail.com>");
+MODULE_DESCRIPTION("Microchip mcp3422/3/4 driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index a952538..8fb5429 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -28,12 +28,16 @@
 #include <linux/iio/driver.h>
 
 #include <linux/mfd/ti_am335x_tscadc.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
 
 struct tiadc_device {
 	struct ti_tscadc_dev *mfd_tscadc;
 	int channels;
 	u8 channel_line[8];
 	u8 channel_step[8];
+	int buffer_en_ch_steps;
+	u16 data[8];
 };
 
 static unsigned int tiadc_readl(struct tiadc_device *adc, unsigned int reg)
@@ -56,8 +60,14 @@ static u32 get_adc_step_mask(struct tiadc_device *adc_dev)
 	return step_en;
 }
 
-static void tiadc_step_config(struct tiadc_device *adc_dev)
+static u32 get_adc_step_bit(struct tiadc_device *adc_dev, int chan)
 {
+	return 1 << adc_dev->channel_step[chan];
+}
+
+static void tiadc_step_config(struct iio_dev *indio_dev)
+{
+	struct tiadc_device *adc_dev = iio_priv(indio_dev);
 	unsigned int stepconfig;
 	int i, steps;
 
@@ -72,7 +82,11 @@ static void tiadc_step_config(struct tiadc_device *adc_dev)
 	 */
 
 	steps = TOTAL_STEPS - adc_dev->channels;
-	stepconfig = STEPCONFIG_AVG_16 | STEPCONFIG_FIFO1;
+	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;
@@ -85,9 +99,175 @@ static void tiadc_step_config(struct tiadc_device *adc_dev)
 		adc_dev->channel_step[i] = steps;
 		steps++;
 	}
+}
+
+static irqreturn_t tiadc_irq_h(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct tiadc_device *adc_dev = iio_priv(indio_dev);
+	unsigned int status, config;
+	status = tiadc_readl(adc_dev, REG_IRQSTATUS);
+
+	/*
+	 * ADC and touchscreen share the IRQ line.
+	 * FIFO0 interrupts are used by TSC. Handle FIFO1 IRQs here only
+	 */
+	if (status & IRQENB_FIFO1OVRRUN) {
+		/* FIFO Overrun. Clear flag. Disable/Enable ADC to recover */
+		config = tiadc_readl(adc_dev, REG_CTRL);
+		config &= ~(CNTRLREG_TSCSSENB);
+		tiadc_writel(adc_dev, REG_CTRL, config);
+		tiadc_writel(adc_dev, REG_IRQSTATUS, IRQENB_FIFO1OVRRUN
+				| IRQENB_FIFO1UNDRFLW | IRQENB_FIFO1THRES);
+		tiadc_writel(adc_dev, REG_CTRL, (config | CNTRLREG_TSCSSENB));
+		return IRQ_HANDLED;
+	} else if (status & IRQENB_FIFO1THRES) {
+		/* Disable irq and wake worker thread */
+		tiadc_writel(adc_dev, REG_IRQCLR, IRQENB_FIFO1THRES);
+		return IRQ_WAKE_THREAD;
+	}
+
+	return IRQ_NONE;
+}
+
+static irqreturn_t tiadc_worker_h(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct tiadc_device *adc_dev = iio_priv(indio_dev);
+	int i, k, fifo1count, read;
+	u16 *data = adc_dev->data;
+
+	fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
+	for (k = 0; k < fifo1count; k = k + i) {
+		for (i = 0; i < (indio_dev->scan_bytes)/2; i++) {
+			read = tiadc_readl(adc_dev, REG_FIFO1);
+			data[i] = read & FIFOREAD_DATA_MASK;
+		}
+		iio_push_to_buffers(indio_dev, (u8 *) data);
+	}
+
+	tiadc_writel(adc_dev, REG_IRQSTATUS, IRQENB_FIFO1THRES);
+	tiadc_writel(adc_dev, REG_IRQENABLE, IRQENB_FIFO1THRES);
+
+	return IRQ_HANDLED;
+}
+
+static int tiadc_buffer_preenable(struct iio_dev *indio_dev)
+{
+	struct tiadc_device *adc_dev = iio_priv(indio_dev);
+	int i, fifo1count, read;
+
+	tiadc_writel(adc_dev, REG_IRQCLR, (IRQENB_FIFO1THRES |
+				IRQENB_FIFO1OVRRUN |
+				IRQENB_FIFO1UNDRFLW));
+
+	/* Flush FIFO. Needed in corner cases in simultaneous tsc/adc use */
+	fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
+	for (i = 0; i < fifo1count; i++)
+		read = tiadc_readl(adc_dev, REG_FIFO1);
+
+	return iio_sw_buffer_preenable(indio_dev);
+}
+
+static int tiadc_buffer_postenable(struct iio_dev *indio_dev)
+{
+	struct tiadc_device *adc_dev = iio_priv(indio_dev);
+	struct iio_buffer *buffer = indio_dev->buffer;
+	unsigned int enb = 0;
+	u8 bit;
+
+	tiadc_step_config(indio_dev);
+	for_each_set_bit(bit, buffer->scan_mask, adc_dev->channels)
+		enb |= (get_adc_step_bit(adc_dev, bit) << 1);
+	adc_dev->buffer_en_ch_steps = enb;
+
+	am335x_tsc_se_set(adc_dev->mfd_tscadc, enb);
+
+	tiadc_writel(adc_dev,  REG_IRQSTATUS, IRQENB_FIFO1THRES
+				| IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW);
+	tiadc_writel(adc_dev,  REG_IRQENABLE, IRQENB_FIFO1THRES
+				| IRQENB_FIFO1OVRRUN);
+
+	return 0;
+}
+
+static int tiadc_buffer_predisable(struct iio_dev *indio_dev)
+{
+	struct tiadc_device *adc_dev = iio_priv(indio_dev);
+	int fifo1count, i, read;
+
+	tiadc_writel(adc_dev, REG_IRQCLR, (IRQENB_FIFO1THRES |
+				IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW));
+	am335x_tsc_se_clr(adc_dev->mfd_tscadc, adc_dev->buffer_en_ch_steps);
+
+	/* Flush FIFO of leftover data in the time it takes to disable adc */
+	fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
+	for (i = 0; i < fifo1count; i++)
+		read = tiadc_readl(adc_dev, REG_FIFO1);
+
+	return 0;
+}
+
+static int tiadc_buffer_postdisable(struct iio_dev *indio_dev)
+{
+	tiadc_step_config(indio_dev);
 
+	return 0;
 }
 
+static const struct iio_buffer_setup_ops tiadc_buffer_setup_ops = {
+	.preenable = &tiadc_buffer_preenable,
+	.postenable = &tiadc_buffer_postenable,
+	.predisable = &tiadc_buffer_predisable,
+	.postdisable = &tiadc_buffer_postdisable,
+};
+
+static int tiadc_iio_buffered_hardware_setup(struct iio_dev *indio_dev,
+	irqreturn_t (*pollfunc_bh)(int irq, void *p),
+	irqreturn_t (*pollfunc_th)(int irq, void *p),
+	int irq,
+	unsigned long flags,
+	const struct iio_buffer_setup_ops *setup_ops)
+{
+	int ret;
+
+	indio_dev->buffer = iio_kfifo_allocate(indio_dev);
+	if (!indio_dev->buffer)
+		return -ENOMEM;
+
+	ret = request_threaded_irq(irq,	pollfunc_th, pollfunc_bh,
+				flags, indio_dev->name, indio_dev);
+	if (ret)
+		goto error_kfifo_free;
+
+	indio_dev->setup_ops = setup_ops;
+	indio_dev->modes |= INDIO_BUFFER_HARDWARE;
+
+	ret = iio_buffer_register(indio_dev,
+				  indio_dev->channels,
+				  indio_dev->num_channels);
+	if (ret)
+		goto error_free_irq;
+
+	return 0;
+
+error_free_irq:
+	free_irq(irq, indio_dev);
+error_kfifo_free:
+	iio_kfifo_free(indio_dev->buffer);
+	return ret;
+}
+
+static void tiadc_iio_buffered_hardware_remove(struct iio_dev *indio_dev)
+{
+	struct tiadc_device *adc_dev = iio_priv(indio_dev);
+
+	free_irq(adc_dev->mfd_tscadc->irq, indio_dev);
+	iio_kfifo_free(indio_dev->buffer);
+	iio_buffer_unregister(indio_dev);
+}
+
+
 static const char * const chan_name_ain[] = {
 	"AIN0",
 	"AIN1",
@@ -120,9 +300,10 @@ static int tiadc_channel_init(struct iio_dev *indio_dev, int channels)
 		chan->channel = adc_dev->channel_line[i];
 		chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
 		chan->datasheet_name = chan_name_ain[chan->channel];
+		chan->scan_index = i;
 		chan->scan_type.sign = 'u';
 		chan->scan_type.realbits = 12;
-		chan->scan_type.storagebits = 32;
+		chan->scan_type.storagebits = 16;
 	}
 
 	indio_dev->channels = chan_array;
@@ -142,11 +323,14 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
 	int i, map_val;
 	unsigned int fifo1count, read, stepid;
-	u32 step = UINT_MAX;
 	bool found = false;
 	u32 step_en;
 	unsigned long timeout = jiffies + usecs_to_jiffies
 				(IDLE_TIMEOUT * adc_dev->channels);
+
+	if (iio_buffer_enabled(indio_dev))
+		return -EBUSY;
+
 	step_en = get_adc_step_mask(adc_dev);
 	am335x_tsc_se_set(adc_dev->mfd_tscadc, step_en);
 
@@ -168,15 +352,6 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
 	 * Hence we need to flush out this data.
 	 */
 
-	for (i = 0; i < ARRAY_SIZE(adc_dev->channel_step); i++) {
-		if (chan->channel == adc_dev->channel_line[i]) {
-			step = adc_dev->channel_step[i];
-			break;
-		}
-	}
-	if (WARN_ON_ONCE(step == UINT_MAX))
-		return -EINVAL;
-
 	fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
 	for (i = 0; i < fifo1count; i++) {
 		read = tiadc_readl(adc_dev, REG_FIFO1);
@@ -186,7 +361,7 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
 		if (stepid == map_val) {
 			read = read & FIFOREAD_DATA_MASK;
 			found = true;
-			*val = read;
+			*val = (u16) read;
 		}
 	}
 
@@ -237,20 +412,33 @@ static int tiadc_probe(struct platform_device *pdev)
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &tiadc_info;
 
-	tiadc_step_config(adc_dev);
+	tiadc_step_config(indio_dev);
+	tiadc_writel(adc_dev, REG_FIFO1THR, FIFO1_THRESHOLD);
 
 	err = tiadc_channel_init(indio_dev, adc_dev->channels);
 	if (err < 0)
 		return err;
 
-	err = iio_device_register(indio_dev);
+	err = tiadc_iio_buffered_hardware_setup(indio_dev,
+		&tiadc_worker_h,
+		&tiadc_irq_h,
+		adc_dev->mfd_tscadc->irq,
+		IRQF_SHARED,
+		&tiadc_buffer_setup_ops);
+
 	if (err)
 		goto err_free_channels;
 
+	err = iio_device_register(indio_dev);
+	if (err)
+		goto err_buffer_unregister;
+
 	platform_set_drvdata(pdev, indio_dev);
 
 	return 0;
 
+err_buffer_unregister:
+	tiadc_iio_buffered_hardware_remove(indio_dev);
 err_free_channels:
 	tiadc_channels_remove(indio_dev);
 	return err;
@@ -263,6 +451,7 @@ static int tiadc_remove(struct platform_device *pdev)
 	u32 step_en;
 
 	iio_device_unregister(indio_dev);
+	tiadc_iio_buffered_hardware_remove(indio_dev);
 	tiadc_channels_remove(indio_dev);
 
 	step_en = get_adc_step_mask(adc_dev);
@@ -301,7 +490,7 @@ static int tiadc_resume(struct device *dev)
 	restore &= ~(CNTRLREG_POWERDOWN);
 	tiadc_writel(adc_dev, REG_CTRL, restore);
 
-	tiadc_step_config(adc_dev);
+	tiadc_step_config(indio_dev);
 
 	return 0;
 }