Merge tag 'togreg-3.6a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

IIO: One new driver and a couple of nice cleanups.

14 files changed, 460 insertions, 33 deletions

diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index 096a6bfe0cdf..4add9bb40eeb 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -571,6 +571,31 @@ int iio_sw_buffer_preenable(struct iio_dev *indio_dev)
 EXPORT_SYMBOL(iio_sw_buffer_preenable);
 
 /**
+ * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected
+ * @indio_dev: the iio device
+ * @mask: scan mask to be checked
+ *
+ * Return true if exactly one bit is set in the scan mask, false otherwise. It
+ * can be used for devices where only one channel can be active for sampling at
+ * a time.
+ */
+bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev,
+	const unsigned long *mask)
+{
+	return bitmap_weight(mask, indio_dev->masklength) == 1;
+}
+EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot);
+
+static bool iio_validate_scan_mask(struct iio_dev *indio_dev,
+	const unsigned long *mask)
+{
+	if (!indio_dev->setup_ops->validate_scan_mask)
+		return true;
+
+	return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask);
+}
+
+/**
  * iio_scan_mask_set() - set particular bit in the scan mask
  * @buffer: the buffer whose scan mask we are interested in
  * @bit: the bit to be set.
@@ -589,27 +614,31 @@ int iio_scan_mask_set(struct iio_dev *indio_dev,
 		return -ENOMEM;
 	if (!indio_dev->masklength) {
 		WARN_ON("trying to set scanmask prior to registering buffer\n");
-		kfree(trialmask);
-		return -EINVAL;
+		goto err_invalid_mask;
 	}
 	bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength);
 	set_bit(bit, trialmask);
 
+	if (!iio_validate_scan_mask(indio_dev, trialmask))
+		goto err_invalid_mask;
+
 	if (indio_dev->available_scan_masks) {
 		mask = iio_scan_mask_match(indio_dev->available_scan_masks,
 					   indio_dev->masklength,
 					   trialmask);
-		if (!mask) {
-			kfree(trialmask);
-			return -EINVAL;
-		}
+		if (!mask)
+			goto err_invalid_mask;
 	}
 	bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength);
 
 	kfree(trialmask);
 
 	return 0;
-};
+
+err_invalid_mask:
+	kfree(trialmask);
+	return -EINVAL;
+}
 EXPORT_SYMBOL_GPL(iio_scan_mask_set);
 
 int iio_scan_mask_query(struct iio_dev *indio_dev,
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index bb3c692e49b8..2ec266ef41a3 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -64,6 +64,7 @@ static const char * const iio_chan_type_name_spec[] = {
 	[IIO_TIMESTAMP] = "timestamp",
 	[IIO_CAPACITANCE] = "capacitance",
 	[IIO_ALTVOLTAGE] = "altvoltage",
+	[IIO_CCT] = "cct",
 };
 
 static const char * const iio_modifier_names[] = {
@@ -74,6 +75,10 @@ static const char * const iio_modifier_names[] = {
 	[IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
 	[IIO_MOD_LIGHT_BOTH] = "both",
 	[IIO_MOD_LIGHT_IR] = "ir",
+	[IIO_MOD_LIGHT_CLEAR] = "clear",
+	[IIO_MOD_LIGHT_RED] = "red",
+	[IIO_MOD_LIGHT_GREEN] = "green",
+	[IIO_MOD_LIGHT_BLUE] = "blue",
 };
 
 /* relies on pairs of these shared then separate */
diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index f3ea90d735b8..91d15d2f694f 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -3,6 +3,18 @@
 #
 menu "Light sensors"
 
+config ADJD_S311
+	tristate "ADJD-S311-CR999 digital color sensor"
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	depends on I2C
+	help
+	 If you say yes here you get support for the Avago ADJD-S311-CR999
+	 digital color light sensor.
+
+	 This driver can also be built as a module.  If so, the module
+	 will be called adjd_s311.
+
 config SENSORS_LM3533
 	tristate "LM3533 ambient light sensor"
 	depends on MFD_LM3533
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index 06fa4d3f33ec..13f8a782d292 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -2,5 +2,6 @@
 # Makefile for IIO Light sensors
 #
 
+obj-$(CONFIG_ADJD_S311)		+= adjd_s311.o
 obj-$(CONFIG_SENSORS_LM3533)	+= lm3533-als.o
 obj-$(CONFIG_VCNL4000)		+= vcnl4000.o
diff --git a/drivers/iio/light/adjd_s311.c b/drivers/iio/light/adjd_s311.c
new file mode 100644
index 000000000000..e4851427d72f
--- /dev/null
+++ b/drivers/iio/light/adjd_s311.c
@@ -0,0 +1,364 @@
+/*
+ * adjd_s311.c - Support for ADJD-S311-CR999 digital color sensor
+ *
+ * Copyright (C) 2012 Peter Meerwald <pmeerw@pmeerw.net>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * driver for ADJD-S311-CR999 digital color sensor (10-bit channels for
+ * red, green, blue, clear); 7-bit I2C slave address 0x74
+ *
+ * limitations: no calibration, no offset mode, no sleep mode
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/bitmap.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define ADJD_S311_DRV_NAME "adjd_s311"
+
+#define ADJD_S311_CTRL		0x00
+#define ADJD_S311_CONFIG	0x01
+#define ADJD_S311_CAP_RED	0x06
+#define ADJD_S311_CAP_GREEN	0x07
+#define ADJD_S311_CAP_BLUE	0x08
+#define ADJD_S311_CAP_CLEAR	0x09
+#define ADJD_S311_INT_RED_LO	0x0a
+#define ADJD_S311_INT_RED_HI	0x0b
+#define ADJD_S311_INT_GREEN_LO	0x0c
+#define ADJD_S311_INT_GREEN_HI	0x0d
+#define ADJD_S311_INT_BLUE_LO	0x0e
+#define ADJD_S311_INT_BLUE_HI	0x0f
+#define ADJD_S311_INT_CLEAR_LO	0x10
+#define ADJD_S311_INT_CLEAR_HI	0x11
+#define ADJD_S311_DATA_RED_LO	0x40
+#define ADJD_S311_DATA_RED_HI	0x41
+#define ADJD_S311_DATA_GREEN_LO	0x42
+#define ADJD_S311_DATA_GREEN_HI	0x43
+#define ADJD_S311_DATA_BLUE_LO	0x44
+#define ADJD_S311_DATA_BLUE_HI	0x45
+#define ADJD_S311_DATA_CLEAR_LO	0x46
+#define ADJD_S311_DATA_CLEAR_HI	0x47
+#define ADJD_S311_OFFSET_RED	0x48
+#define ADJD_S311_OFFSET_GREEN	0x49
+#define ADJD_S311_OFFSET_BLUE	0x4a
+#define ADJD_S311_OFFSET_CLEAR	0x4b
+
+#define ADJD_S311_CTRL_GOFS	0x02
+#define ADJD_S311_CTRL_GSSR	0x01
+#define ADJD_S311_CAP_MASK	0x0f
+#define ADJD_S311_INT_MASK	0x0fff
+#define ADJD_S311_DATA_MASK	0x03ff
+
+struct adjd_s311_data {
+	struct i2c_client *client;
+	u16 *buffer;
+};
+
+enum adjd_s311_channel_idx {
+	IDX_RED, IDX_GREEN, IDX_BLUE, IDX_CLEAR
+};
+
+#define ADJD_S311_DATA_REG(chan) (ADJD_S311_DATA_RED_LO + (chan) * 2)
+#define ADJD_S311_INT_REG(chan) (ADJD_S311_INT_RED_LO + (chan) * 2)
+#define ADJD_S311_CAP_REG(chan) (ADJD_S311_CAP_RED + (chan))
+
+static int adjd_s311_req_data(struct iio_dev *indio_dev)
+{
+	struct adjd_s311_data *data = iio_priv(indio_dev);
+	int tries = 10;
+
+	int ret = i2c_smbus_write_byte_data(data->client, ADJD_S311_CTRL,
+		ADJD_S311_CTRL_GSSR);
+	if (ret < 0)
+		return ret;
+
+	while (tries--) {
+		ret = i2c_smbus_read_byte_data(data->client, ADJD_S311_CTRL);
+		if (ret < 0)
+			return ret;
+		if (!(ret & ADJD_S311_CTRL_GSSR))
+			break;
+		msleep(20);
+	}
+
+	if (tries < 0) {
+		dev_err(&data->client->dev,
+			"adjd_s311_req_data() failed, data not ready\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int adjd_s311_read_data(struct iio_dev *indio_dev, u8 reg, int *val)
+{
+	struct adjd_s311_data *data = iio_priv(indio_dev);
+
+	int ret = adjd_s311_req_data(indio_dev);
+	if (ret < 0)
+		return ret;
+
+	ret = i2c_smbus_read_word_data(data->client, reg);
+	if (ret < 0)
+		return ret;
+
+	*val = ret & ADJD_S311_DATA_MASK;
+
+	return 0;
+}
+
+static ssize_t adjd_s311_read_int_time(struct iio_dev *indio_dev,
+	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
+{
+	struct adjd_s311_data *data = iio_priv(indio_dev);
+	s32 ret;
+
+	ret = i2c_smbus_read_word_data(data->client,
+		ADJD_S311_INT_REG(chan->address));
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%d\n", ret & ADJD_S311_INT_MASK);
+}
+
+static ssize_t adjd_s311_write_int_time(struct iio_dev *indio_dev,
+	 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
+	 size_t len)
+{
+	struct adjd_s311_data *data = iio_priv(indio_dev);
+	unsigned long int_time;
+	int ret;
+
+	ret = kstrtoul(buf, 10, &int_time);
+	if (ret)
+		return ret;
+
+	if (int_time > ADJD_S311_INT_MASK)
+		return -EINVAL;
+
+	ret = i2c_smbus_write_word_data(data->client,
+		ADJD_S311_INT_REG(chan->address), int_time);
+	if (ret < 0)
+		return ret;
+
+	return len;
+}
+
+static irqreturn_t adjd_s311_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct adjd_s311_data *data = iio_priv(indio_dev);
+	struct iio_buffer *buffer = indio_dev->buffer;
+	s64 time_ns = iio_get_time_ns();
+	int len = 0;
+	int i, j = 0;
+
+	int ret = adjd_s311_req_data(indio_dev);
+	if (ret < 0)
+		goto done;
+
+	for_each_set_bit(i, indio_dev->active_scan_mask,
+		indio_dev->masklength) {
+		ret = i2c_smbus_read_word_data(data->client,
+			ADJD_S311_DATA_REG(i));
+		if (ret < 0)
+			goto done;
+
+		data->buffer[j++] = ret & ADJD_S311_DATA_MASK;
+		len += 2;
+	}
+
+	if (indio_dev->scan_timestamp)
+		*(s64 *)((phys_addr_t)data->buffer + ALIGN(len, sizeof(s64)))
+			= time_ns;
+	iio_push_to_buffer(buffer, (u8 *)data->buffer, time_ns);
+
+done:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static const struct iio_chan_spec_ext_info adjd_s311_ext_info[] = {
+	{
+		.name = "integration_time",
+		.read = adjd_s311_read_int_time,
+		.write = adjd_s311_write_int_time,
+	},
+	{ }
+};
+
+#define ADJD_S311_CHANNEL(_color, _scan_idx) { \
+	.type = IIO_INTENSITY, \
+	.modified = 1, \
+	.address = (IDX_##_color), \
+	.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
+		IIO_CHAN_INFO_HARDWAREGAIN_SEPARATE_BIT, \
+	.channel2 = (IIO_MOD_LIGHT_##_color), \
+	.scan_index = (_scan_idx), \
+	.scan_type = IIO_ST('u', 10, 16, 0), \
+	.ext_info = adjd_s311_ext_info, \
+}
+
+static const struct iio_chan_spec adjd_s311_channels[] = {
+	ADJD_S311_CHANNEL(RED, 0),
+	ADJD_S311_CHANNEL(GREEN, 1),
+	ADJD_S311_CHANNEL(BLUE, 2),
+	ADJD_S311_CHANNEL(CLEAR, 3),
+	IIO_CHAN_SOFT_TIMESTAMP(4),
+};
+
+static int adjd_s311_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2, long mask)
+{
+	struct adjd_s311_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		ret = adjd_s311_read_data(indio_dev, chan->address, val);
+		if (ret < 0)
+			return ret;
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_HARDWAREGAIN:
+		ret = i2c_smbus_read_byte_data(data->client,
+			ADJD_S311_CAP_REG(chan->address));
+		if (ret < 0)
+			return ret;
+		*val = ret & ADJD_S311_CAP_MASK;
+		return IIO_VAL_INT;
+	}
+	return -EINVAL;
+}
+
+static int adjd_s311_write_raw(struct iio_dev *indio_dev,
+			       struct iio_chan_spec const *chan,
+			       int val, int val2, long mask)
+{
+	struct adjd_s311_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_HARDWAREGAIN:
+		if (val < 0 || val > ADJD_S311_CAP_MASK)
+			return -EINVAL;
+
+		ret = i2c_smbus_write_byte_data(data->client,
+			ADJD_S311_CAP_REG(chan->address), val);
+		return ret;
+	}
+	return -EINVAL;
+}
+
+static int adjd_s311_update_scan_mode(struct iio_dev *indio_dev,
+	const unsigned long *scan_mask)
+{
+	struct adjd_s311_data *data = iio_priv(indio_dev);
+	data->buffer = krealloc(data->buffer, indio_dev->scan_bytes,
+				GFP_KERNEL);
+	if (!data->buffer)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static const struct iio_info adjd_s311_info = {
+	.read_raw = adjd_s311_read_raw,
+	.write_raw = adjd_s311_write_raw,
+	.update_scan_mode = adjd_s311_update_scan_mode,
+	.driver_module = THIS_MODULE,
+};
+
+static int __devinit adjd_s311_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	struct adjd_s311_data *data;
+	struct iio_dev *indio_dev;
+	int err;
+
+	indio_dev = iio_device_alloc(sizeof(*data));
+	if (indio_dev == NULL) {
+		err = -ENOMEM;
+		goto exit;
+	}
+	data = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	data->client = client;
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &adjd_s311_info;
+	indio_dev->name = ADJD_S311_DRV_NAME;
+	indio_dev->channels = adjd_s311_channels;
+	indio_dev->num_channels = ARRAY_SIZE(adjd_s311_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	err = iio_triggered_buffer_setup(indio_dev, NULL,
+		adjd_s311_trigger_handler, NULL);
+	if (err < 0)
+		goto exit_free_device;
+
+	err = iio_device_register(indio_dev);
+	if (err)
+		goto exit_unreg_buffer;
+
+	dev_info(&client->dev, "ADJD-S311 color sensor registered\n");
+
+	return 0;
+
+exit_unreg_buffer:
+	iio_triggered_buffer_cleanup(indio_dev);
+exit_free_device:
+	iio_device_free(indio_dev);
+exit:
+	return err;
+}
+
+static int __devexit adjd_s311_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct adjd_s311_data *data = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	iio_triggered_buffer_cleanup(indio_dev);
+	kfree(data->buffer);
+	iio_device_free(indio_dev);
+
+	return 0;
+}
+
+static const struct i2c_device_id adjd_s311_id[] = {
+	{ "adjd_s311", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, adjd_s311_id);
+
+static struct i2c_driver adjd_s311_driver = {
+	.driver = {
+		.name	= ADJD_S311_DRV_NAME,
+	},
+	.probe		= adjd_s311_probe,
+	.remove		= __devexit_p(adjd_s311_remove),
+	.id_table	= adjd_s311_id,
+};
+module_i2c_driver(adjd_s311_driver);
+
+MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
+MODULE_DESCRIPTION("ADJD-S311 color sensor");
+MODULE_LICENSE("GPL");
diff --git a/drivers/staging/iio/Documentation/sysfs-bus-iio-light b/drivers/staging/iio/Documentation/sysfs-bus-iio-light
index d52be0385dc4..17e5c9c515d4 100644
--- a/drivers/staging/iio/Documentation/sysfs-bus-iio-light
+++ b/drivers/staging/iio/Documentation/sysfs-bus-iio-light
@@ -82,3 +82,26 @@ Contact:	linux-iio@vger.kernel.org
 Description:
 		This property gets/sets the table of coefficients
 		used in calculating illuminance in lux.
+
+What:		/sys/bus/iio/devices/device[n]/in_intensity_clear[_input|_raw]
+What:		/sys/bus/iio/devices/device[n]/in_intensity_red[_input|_raw]
+What:		/sys/bus/iio/devices/device[n]/in_intensity_green[_input|_raw]
+What:		/sys/bus/iio/devices/device[n]/in_intensity_blue[_input|_raw]
+KernelVersion:	3.6.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		This property is supported by sensors that have a RGBC
+		sensing mode. This value should be the output from a reading
+		and if expressed in SI units, should include _input. If this
+		value is not in SI units (irradiance, uW/mm^2), then it should
+		include _raw.
+
+What:		/sys/bus/iio/devices/device[n]/in_cct0[_input|_raw]
+KernelVersion:	3.6.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		This should return the correlated color temperature from the
+		light sensor. If it comes back in SI units, it should also
+		include _input else it should include _raw to signify it is not
+		in SI units.
+
diff --git a/drivers/staging/iio/adc/ad7192.c b/drivers/staging/iio/adc/ad7192.c
index 839f17c4e33d..22c3923d55eb 100644
--- a/drivers/staging/iio/adc/ad7192.c
+++ b/drivers/staging/iio/adc/ad7192.c
@@ -146,7 +146,6 @@ struct ad7192_state {
 	u32				mode;
 	u32				conf;
 	u32				scale_avail[8][2];
-	long				available_scan_masks[9];
 	u8				gpocon;
 	u8				devid;
 	/*
@@ -538,6 +537,7 @@ static const struct iio_buffer_setup_ops ad7192_ring_setup_ops = {
 	.postenable = &iio_triggered_buffer_postenable,
 	.predisable = &iio_triggered_buffer_predisable,
 	.postdisable = &ad7192_ring_postdisable,
+	.validate_scan_mask = &iio_validate_scan_mask_onehot,
 };
 
 static int ad7192_register_ring_funcs_and_init(struct iio_dev *indio_dev)
@@ -984,7 +984,7 @@ static int __devinit ad7192_probe(struct spi_device *spi)
 	struct ad7192_platform_data *pdata = spi->dev.platform_data;
 	struct ad7192_state *st;
 	struct iio_dev *indio_dev;
-	int ret, i , voltage_uv = 0;
+	int ret , voltage_uv = 0;
 
 	if (!pdata) {
 		dev_err(&spi->dev, "no platform data?\n");
@@ -1028,17 +1028,11 @@ static int __devinit ad7192_probe(struct spi_device *spi)
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->channels = ad7192_channels;
 	indio_dev->num_channels = ARRAY_SIZE(ad7192_channels);
-	indio_dev->available_scan_masks = st->available_scan_masks;
 	if (st->devid == ID_AD7195)
 		indio_dev->info = &ad7195_info;
 	else
 		indio_dev->info = &ad7192_info;
 
-	for (i = 0; i < indio_dev->num_channels; i++)
-		st->available_scan_masks[i] = (1 << i) | (1 <<
-			indio_dev->channels[indio_dev->num_channels - 1].
-			scan_index);
-
 	init_waitqueue_head(&st->wq_data_avail);
 
 	ret = ad7192_register_ring_funcs_and_init(indio_dev);
diff --git a/drivers/staging/iio/adc/ad7793.c b/drivers/staging/iio/adc/ad7793.c
index eaa0cc939165..76fdd7145fc5 100644
--- a/drivers/staging/iio/adc/ad7793.c
+++ b/drivers/staging/iio/adc/ad7793.c
@@ -52,8 +52,7 @@ struct ad7793_state {
 	u16				mode;
 	u16				conf;
 	u32				scale_avail[8][2];
-	/* Note this uses fact that 8 the mask always fits in a long */
-	unsigned long			available_scan_masks[7];
+
 	/*
 	 * DMA (thus cache coherency maintenance) requires the
 	 * transfer buffers to live in their own cache lines.
@@ -403,6 +402,7 @@ static const struct iio_buffer_setup_ops ad7793_ring_setup_ops = {
 	.postenable = &iio_triggered_buffer_postenable,
 	.predisable = &iio_triggered_buffer_predisable,
 	.postdisable = &ad7793_ring_postdisable,
+	.validate_scan_mask = &iio_validate_scan_mask_onehot,
 };
 
 static int ad7793_register_ring_funcs_and_init(struct iio_dev *indio_dev)
@@ -864,7 +864,7 @@ static int __devinit ad7793_probe(struct spi_device *spi)
 	struct ad7793_platform_data *pdata = spi->dev.platform_data;
 	struct ad7793_state *st;
 	struct iio_dev *indio_dev;
-	int ret, i, voltage_uv = 0;
+	int ret, voltage_uv = 0;
 
 	if (!pdata) {
 		dev_err(&spi->dev, "no platform data?\n");
@@ -910,17 +910,9 @@ static int __devinit ad7793_probe(struct spi_device *spi)
 	indio_dev->name = spi_get_device_id(spi)->name;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->channels = st->chip_info->channel;
-	indio_dev->available_scan_masks = st->available_scan_masks;
 	indio_dev->num_channels = 7;
 	indio_dev->info = &ad7793_info;
 
-	for (i = 0; i < indio_dev->num_channels; i++) {
-		set_bit(i, &st->available_scan_masks[i]);
-		set_bit(indio_dev->
-			channels[indio_dev->num_channels - 1].scan_index,
-			&st->available_scan_masks[i]);
-	}
-
 	init_waitqueue_head(&st->wq_data_avail);
 
 	ret = ad7793_register_ring_funcs_and_init(indio_dev);
diff --git a/drivers/staging/iio/meter/ade7758.h b/drivers/staging/iio/meter/ade7758.h
index bdd1b05bf7a5..ec202b4ecfb2 100644
--- a/drivers/staging/iio/meter/ade7758.h
+++ b/drivers/staging/iio/meter/ade7758.h
@@ -122,7 +122,6 @@ struct ade7758_state {
 	u8			*tx;
 	u8			*rx;
 	struct mutex		buf_lock;
-	unsigned long		available_scan_masks[AD7758_NUM_WAVESRC];
 	struct iio_chan_spec	*ade7758_ring_channels;
 	struct spi_transfer	ring_xfer[4];
 	struct spi_message	ring_msg;
diff --git a/drivers/staging/iio/meter/ade7758_core.c b/drivers/staging/iio/meter/ade7758_core.c
index 96d6114a31aa..7014a0078446 100644
--- a/drivers/staging/iio/meter/ade7758_core.c
+++ b/drivers/staging/iio/meter/ade7758_core.c
@@ -883,7 +883,7 @@ static const struct iio_info ade7758_info = {
 
 static int __devinit ade7758_probe(struct spi_device *spi)
 {
-	int i, ret;
+	int ret;
 	struct ade7758_state *st;
 	struct iio_dev *indio_dev = iio_device_alloc(sizeof(*st));
 
@@ -916,11 +916,6 @@ static int __devinit ade7758_probe(struct spi_device *spi)
 	indio_dev->info = &ade7758_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
-	for (i = 0; i < AD7758_NUM_WAVESRC; i++)
-		set_bit(i, &st->available_scan_masks[i]);
-
-	indio_dev->available_scan_masks = st->available_scan_masks;
-
 	ret = ade7758_configure_ring(indio_dev);
 	if (ret)
 		goto error_free_tx;
diff --git a/drivers/staging/iio/meter/ade7758_ring.c b/drivers/staging/iio/meter/ade7758_ring.c
index 92159f208d14..1ce10b21f4d6 100644
--- a/drivers/staging/iio/meter/ade7758_ring.c
+++ b/drivers/staging/iio/meter/ade7758_ring.c
@@ -114,6 +114,7 @@ static const struct iio_buffer_setup_ops ade7758_ring_setup_ops = {
 	.preenable = &ade7758_ring_preenable,
 	.postenable = &iio_triggered_buffer_postenable,
 	.predisable = &iio_triggered_buffer_predisable,
+	.validate_scan_mask = &iio_validate_scan_mask_onehot,
 };
 
 void ade7758_unconfigure_ring(struct iio_dev *indio_dev)
diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h
index 2a2b6b4d8d05..8ba516fc2ec6 100644
--- a/include/linux/iio/buffer.h
+++ b/include/linux/iio/buffer.h
@@ -177,6 +177,9 @@ ssize_t iio_buffer_show_enable(struct device *dev,
 
 int iio_sw_buffer_preenable(struct iio_dev *indio_dev);
 
+bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev,
+	const unsigned long *mask);
+
 #else /* CONFIG_IIO_BUFFER */
 
 static inline int iio_buffer_register(struct iio_dev *indio_dev,
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
index 2afbb6f01afc..be82936c4089 100644
--- a/include/linux/iio/iio.h
+++ b/include/linux/iio/iio.h
@@ -363,12 +363,16 @@ struct iio_info {
  * @predisable:		[DRIVER] function to run prior to marking buffer
  *			disabled
  * @postdisable:	[DRIVER] function to run after marking buffer disabled
+ * @validate_scan_mask: [DRIVER] function callback to check whether a given
+ *			scan mask is valid for the device.
  */
 struct iio_buffer_setup_ops {
 	int				(*preenable)(struct iio_dev *);
 	int				(*postenable)(struct iio_dev *);
 	int				(*predisable)(struct iio_dev *);
 	int				(*postdisable)(struct iio_dev *);
+	bool (*validate_scan_mask)(struct iio_dev *indio_dev,
+				   const unsigned long *scan_mask);
 };
 
 /**
diff --git a/include/linux/iio/types.h b/include/linux/iio/types.h
index e25040173346..44e397705d7f 100644
--- a/include/linux/iio/types.h
+++ b/include/linux/iio/types.h
@@ -27,6 +27,7 @@ enum iio_chan_type {
 	IIO_TIMESTAMP,
 	IIO_CAPACITANCE,
 	IIO_ALTVOLTAGE,
+	IIO_CCT,
 };
 
 enum iio_modifier {
@@ -46,6 +47,10 @@ enum iio_modifier {
 	IIO_MOD_LIGHT_IR,
 	IIO_MOD_ROOT_SUM_SQUARED_X_Y,
 	IIO_MOD_SUM_SQUARED_X_Y_Z,
+	IIO_MOD_LIGHT_CLEAR,
+	IIO_MOD_LIGHT_RED,
+	IIO_MOD_LIGHT_GREEN,
+	IIO_MOD_LIGHT_BLUE,
 };
 
 #define IIO_VAL_INT 1