Merge tag 'iio-for-4.17b' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Second set of new device support, features and cleanup for IIO in the 4.17 cycle

The uptick in staging cleanup is partly due to GSoC Applications
process being underway and one of Daniel's tasks being to try
cleaning up an IIO driver to move out of staging.
Naturally there is some normal staging cleanup progress in here
as well.

New device support
* Microchip mcp4018
  - New driver supproting MCP4017, MCP4018 and MCP4019 digital pots.
* On Semiconductor lv0104cs
  - New driver to support this ambient light sensor.

Cleanup
* axp20x_adc
  - remove a !! in favour of clear ternary operator.
* ad2s1210 (staging cleanup)
  - Reorganise to avoid ending a line with [
  - Remove some unnecessary defines.
  - Remove unsed variable.
* ad5380
  - Replace magic 0 with IIO_CHAN_INFO_RAW
* ad5764
  - Replace magic 0 with IIO_CHA_INFO_RAW
* ad7150 (staging cleanup)
  - Align arguements with parenthesis.
* ad7152 (staging cleanup)
  - Align arguements.
* ad7746 (staging cleanup)
  - Align arguements.
* ad7816
  - Remove pointless void pointer cast.
* ade7753
  - Replace IIO_DEV_ATTR_CH_OFF with equivalent to avoid confusing
    checkpatch (this macro didn't really help anyway).  Also drop the
    macro from the meter.h header.
* ade7754 (staging cleanup)
  - Add names to funciton definition arguements.
  - Align arguements with open parenthesis where possible.
* ade7758 (staging cleanup)
  - Remove __func__ from dev_dbg statements as provided by dynamic
    debug anyway.
  - Align arguements with open parenthesis where possible.
* ade7759 (staging cleanup)
  - Replace IIO_DEV_ATTR_CH_OFF with equiavalent to avoid confusing
    checkpatch.
* adis16201 (staging cleanup)
  - Headers in alphabetical order.
  - Blank lines before returns.
* adis16209 (staging cleanup)
  - Headers in alphabetical order
  - Change some definition names to make them more meaningful (2 rounds
    of this).
  - Add explicit _REG prefix to register names to make them
    obviously different from fields within those registers.
  - Remove some superflous comments and group definitions better.
  - Use a switch statement to make it semantically obvious that we
    only have two options (rather than an unlimited 'else').
  - Use sign_extent32 instead of open coding.
* adt7316 (staging cleanup)
  - Move an export next to symbol.
* bmc150
  - drop redundant __func__ in dynamic debug.
* ccs811
  - Rename varaible to better reflect what it does.
* cros_ec
  - Reduce sampling frequency before suspending to avoid preventing
    suspend.
* dummy
  - Correct whitespace in Kconfig.
  - Add extra description in Kconfig.
* ds1803
  - Remove a VLA which we always know is 2 long.
* hid-sensor-accel
  - Replace magic number 0 by IIO_CHAN_INFO_RAW.
* hid-sensor-gyro
  - Replace magic number 0 by IIO_CHAN_INFO_RAW.
* hid-sensor-light
  - Replace magic number 0 by IIO_CHAN_INFO_RAW.
* hid-sensor-magn
  - Replace magic number 0 by IIO_CHAN_INFO_RAW.
* lm3533
  - Replace magic number 0 by IIO_CHAN_INFO_RAW
* mlx90632
  - Squash a smatch warning - no runtime effect.
* stm32_dfsdm:
  - Cleanup the dt bindings.
* sx9500
  - Add GPIO ACPI mapping table to behave correctly when firmware
    doesn't provide the mapping.
* tsl2x7x (staging cleanup)
  - Fix the proximity sensor functionality.
  - Remove platform data provided power functions.  There are much
    better ways to do this these days.
  - Introduce some common functions to avoid various repititions.
  - Stop using mutex_trylock when mutex_lock and wait a bit is fine.
  - Improve error handling in various places.
  - Drop some 'Camel case' (which wasn't actually strickly camel case
    but was a bit odd.
  - Drop some _available sysfs attributes for things that don't exist
    (for particular supported parts).

44 files changed, 1236 insertions, 461 deletions

diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.txt b/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.txt
index 911492da48f3..ed7520d1d051 100644
--- a/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.txt
+++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.txt
@@ -32,6 +32,10 @@ Optional properties:
 		  to "clock" property. Frequency must be a multiple of the rcc
 		  clock frequency. If not, SPI CLKOUT frequency will not be
 		  accurate.
+- pinctrl-names:	Set to "default".
+- pinctrl-0:		List of phandles pointing to pin configuration
+			nodes to set pins in mode of operation for dfsdm
+			on external pin.
 
 Contents of a STM32 DFSDM child nodes:
 --------------------------------------
@@ -68,8 +72,8 @@ Optional properties:
 - st,adc-channel-types:	Single-ended channel input type.
 			- "SPI_R": SPI with data on rising edge (default)
 			- "SPI_F": SPI with data on falling edge
-			- "MANCH_R": manchester codec, rising edge = logic 0
-			- "MANCH_F": manchester codec, falling edge = logic 1
+			- "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
+			- "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
 - st,adc-channel-clk-src: Conversion clock source.
 			  - "CLKIN": external SPI clock (CLKIN x)
 			  - "CLKOUT": internal SPI clock (CLKOUT) (default)
diff --git a/MAINTAINERS b/MAINTAINERS
index c3c2b7595cba..46156e223ab7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8585,11 +8585,12 @@ W:	https://linuxtv.org
 S:	Maintained
 F:	drivers/media/radio/radio-maxiradio*
 
-MCP4531 MICROCHIP DIGITAL POTENTIOMETER DRIVER
+MCP4018 AND MCP4531 MICROCHIP DIGITAL POTENTIOMETER DRIVERS
 M:	Peter Rosin <peda@axentia.se>
 L:	linux-iio@vger.kernel.org
 S:	Maintained
 F:	Documentation/ABI/testing/sysfs-bus-iio-potentiometer-mcp4531
+F:	drivers/iio/potentiometer/mcp4018.c
 F:	drivers/iio/potentiometer/mcp4531.c
 
 MEASUREMENT COMPUTING CIO-DAC IIO DRIVER
diff --git a/drivers/iio/accel/bmc150-accel-core.c b/drivers/iio/accel/bmc150-accel-core.c
index 870f92ef61c2..208f2d9f0e8a 100644
--- a/drivers/iio/accel/bmc150-accel-core.c
+++ b/drivers/iio/accel/bmc150-accel-core.c
@@ -336,8 +336,7 @@ static int bmc150_accel_update_slope(struct bmc150_accel_data *data)
 		return ret;
 	}
 
-	dev_dbg(dev, "%s: %x %x\n", __func__, data->slope_thres,
-		data->slope_dur);
+	dev_dbg(dev, "%x %x\n", data->slope_thres, data->slope_dur);
 
 	return ret;
 }
@@ -1716,7 +1715,6 @@ static int bmc150_accel_runtime_suspend(struct device *dev)
 	struct bmc150_accel_data *data = iio_priv(indio_dev);
 	int ret;
 
-	dev_dbg(dev,  __func__);
 	ret = bmc150_accel_set_mode(data, BMC150_ACCEL_SLEEP_MODE_SUSPEND, 0);
 	if (ret < 0)
 		return -EAGAIN;
@@ -1731,8 +1729,6 @@ static int bmc150_accel_runtime_resume(struct device *dev)
 	int ret;
 	int sleep_val;
 
-	dev_dbg(dev,  __func__);
-
 	ret = bmc150_accel_set_mode(data, BMC150_ACCEL_SLEEP_MODE_NORMAL, 0);
 	if (ret < 0)
 		return ret;
diff --git a/drivers/iio/accel/hid-sensor-accel-3d.c b/drivers/iio/accel/hid-sensor-accel-3d.c
index c066a3bdbff7..41d97faf5013 100644
--- a/drivers/iio/accel/hid-sensor-accel-3d.c
+++ b/drivers/iio/accel/hid-sensor-accel-3d.c
@@ -155,7 +155,7 @@ static int accel_3d_read_raw(struct iio_dev *indio_dev,
 	*val = 0;
 	*val2 = 0;
 	switch (mask) {
-	case 0:
+	case IIO_CHAN_INFO_RAW:
 		hid_sensor_power_state(&accel_state->common_attributes, true);
 		report_id = accel_state->accel[chan->scan_index].report_id;
 		address = accel_3d_addresses[chan->scan_index];
diff --git a/drivers/iio/adc/axp20x_adc.c b/drivers/iio/adc/axp20x_adc.c
index 7cdb8bc8cde6..5be789269353 100644
--- a/drivers/iio/adc/axp20x_adc.c
+++ b/drivers/iio/adc/axp20x_adc.c
@@ -445,7 +445,7 @@ static int axp20x_adc_offset_voltage(struct iio_dev *indio_dev, int channel,
 		return -EINVAL;
 	}
 
-	*val = !!(*val) * 700000;
+	*val = *val ? 700000 : 0;
 
 	return IIO_VAL_INT;
 }
@@ -542,15 +542,17 @@ static int axp20x_write_raw(struct iio_dev *indio_dev,
 	if (val != 0 && val != 700000)
 		return -EINVAL;
 
+	val = val ? 1 : 0;
+
 	switch (chan->channel) {
 	case AXP20X_GPIO0_V:
 		reg = AXP20X_GPIO10_IN_RANGE_GPIO0;
-		regval = AXP20X_GPIO10_IN_RANGE_GPIO0_VAL(!!val);
+		regval = AXP20X_GPIO10_IN_RANGE_GPIO0_VAL(val);
 		break;
 
 	case AXP20X_GPIO1_V:
 		reg = AXP20X_GPIO10_IN_RANGE_GPIO1;
-		regval = AXP20X_GPIO10_IN_RANGE_GPIO1_VAL(!!val);
+		regval = AXP20X_GPIO10_IN_RANGE_GPIO1_VAL(val);
 		break;
 
 	default:
diff --git a/drivers/iio/chemical/ccs811.c b/drivers/iio/chemical/ccs811.c
index cfaf86b248d9..e092ffe1431e 100644
--- a/drivers/iio/chemical/ccs811.c
+++ b/drivers/iio/chemical/ccs811.c
@@ -69,7 +69,7 @@ struct ccs811_reading {
 	__be16 voc;
 	u8 status;
 	u8 error;
-	__be16 resistance;
+	__be16 raw_data;
 } __attribute__((__packed__));
 
 struct ccs811_data {
@@ -210,12 +210,12 @@ static int ccs811_read_raw(struct iio_dev *indio_dev,
 
 		switch (chan->type) {
 		case IIO_VOLTAGE:
-			*val = be16_to_cpu(data->buffer.resistance) &
+			*val = be16_to_cpu(data->buffer.raw_data) &
 					   CCS811_VOLTAGE_MASK;
 			ret = IIO_VAL_INT;
 			break;
 		case IIO_CURRENT:
-			*val = be16_to_cpu(data->buffer.resistance) >> 10;
+			*val = be16_to_cpu(data->buffer.raw_data) >> 10;
 			ret = IIO_VAL_INT;
 			break;
 		case IIO_CONCENTRATION:
diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
index 7d30c59da3e2..705cb3e72663 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
@@ -289,6 +289,7 @@ MODULE_DEVICE_TABLE(platform, cros_ec_sensors_ids);
 static struct platform_driver cros_ec_sensors_platform_driver = {
 	.driver = {
 		.name	= "cros-ec-sensors",
+		.pm	= &cros_ec_sensors_pm_ops,
 	},
 	.probe		= cros_ec_sensors_probe,
 	.id_table	= cros_ec_sensors_ids,
diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
index 416cae5ebbd0..a620eb5ce202 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
@@ -446,5 +446,54 @@ int cros_ec_sensors_core_write(struct cros_ec_sensors_core_state *st,
 }
 EXPORT_SYMBOL_GPL(cros_ec_sensors_core_write);
 
+static int __maybe_unused cros_ec_sensors_prepare(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+	struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
+
+	if (st->curr_sampl_freq == 0)
+		return 0;
+
+	/*
+	 * If the sensors are sampled at high frequency, we will not be able to
+	 * sleep. Set sampling to a long period if necessary.
+	 */
+	if (st->curr_sampl_freq < CROS_EC_MIN_SUSPEND_SAMPLING_FREQUENCY) {
+		mutex_lock(&st->cmd_lock);
+		st->param.cmd = MOTIONSENSE_CMD_EC_RATE;
+		st->param.ec_rate.data = CROS_EC_MIN_SUSPEND_SAMPLING_FREQUENCY;
+		cros_ec_motion_send_host_cmd(st, 0);
+		mutex_unlock(&st->cmd_lock);
+	}
+	return 0;
+}
+
+static void __maybe_unused cros_ec_sensors_complete(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+	struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
+
+	if (st->curr_sampl_freq == 0)
+		return;
+
+	if (st->curr_sampl_freq < CROS_EC_MIN_SUSPEND_SAMPLING_FREQUENCY) {
+		mutex_lock(&st->cmd_lock);
+		st->param.cmd = MOTIONSENSE_CMD_EC_RATE;
+		st->param.ec_rate.data = st->curr_sampl_freq;
+		cros_ec_motion_send_host_cmd(st, 0);
+		mutex_unlock(&st->cmd_lock);
+	}
+}
+
+const struct dev_pm_ops cros_ec_sensors_pm_ops = {
+#ifdef CONFIG_PM_SLEEP
+	.prepare = cros_ec_sensors_prepare,
+	.complete = cros_ec_sensors_complete
+#endif
+};
+EXPORT_SYMBOL_GPL(cros_ec_sensors_pm_ops);
+
 MODULE_DESCRIPTION("ChromeOS EC sensor hub core functions");
 MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.h b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.h
index 8bc2ca3c2e2e..2edf68dc7336 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.h
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.h
@@ -169,6 +169,8 @@ int cros_ec_sensors_core_write(struct cros_ec_sensors_core_state *st,
 			       struct iio_chan_spec const *chan,
 			       int val, int val2, long mask);
 
+extern const struct dev_pm_ops cros_ec_sensors_pm_ops;
+
 /* List of extended channel specification for all sensors */
 extern const struct iio_chan_spec_ext_info cros_ec_sensors_ext_info[];
 
diff --git a/drivers/iio/dac/ad5380.c b/drivers/iio/dac/ad5380.c
index 845fd1c0fd9d..873c2bf637c0 100644
--- a/drivers/iio/dac/ad5380.c
+++ b/drivers/iio/dac/ad5380.c
@@ -158,7 +158,7 @@ static unsigned int ad5380_info_to_reg(struct iio_chan_spec const *chan,
 	long info)
 {
 	switch (info) {
-	case 0:
+	case IIO_CHAN_INFO_RAW:
 		return AD5380_REG_DATA(chan->address);
 	case IIO_CHAN_INFO_CALIBBIAS:
 		return AD5380_REG_OFFSET(chan->address);
diff --git a/drivers/iio/dac/ad5764.c b/drivers/iio/dac/ad5764.c
index 033f20eca616..9333177062c0 100644
--- a/drivers/iio/dac/ad5764.c
+++ b/drivers/iio/dac/ad5764.c
@@ -168,7 +168,7 @@ static int ad5764_read(struct iio_dev *indio_dev, unsigned int reg,
 static int ad5764_chan_info_to_reg(struct iio_chan_spec const *chan, long info)
 {
 	switch (info) {
-	case 0:
+	case IIO_CHAN_INFO_RAW:
 		return AD5764_REG_DATA(chan->address);
 	case IIO_CHAN_INFO_CALIBBIAS:
 		return AD5764_REG_OFFSET(chan->address);
diff --git a/drivers/iio/dummy/Kconfig b/drivers/iio/dummy/Kconfig
index 5a29fbd3c531..c4fd108e91d3 100644
--- a/drivers/iio/dummy/Kconfig
+++ b/drivers/iio/dummy/Kconfig
@@ -9,20 +9,24 @@ config IIO_DUMMY_EVGEN
 	tristate
 
 config IIO_SIMPLE_DUMMY
-       tristate "An example driver with no hardware requirements"
-       depends on IIO_SW_DEVICE
-       help
-	 Driver intended mainly as documentation for how to write
-	 a driver. May also be useful for testing userspace code
-	 without hardware.
+	tristate "An example driver with no hardware requirements"
+	depends on IIO_SW_DEVICE
+	help
+	  Driver intended mainly as documentation for how to write
+	  a driver. May also be useful for testing userspace code
+	  without hardware.
 
 if IIO_SIMPLE_DUMMY
 
 config IIO_SIMPLE_DUMMY_EVENTS
-       bool "Event generation support"
-       select IIO_DUMMY_EVGEN
-       help
-         Add some dummy events to the simple dummy driver.
+	bool "Event generation support"
+	select IIO_DUMMY_EVGEN
+	help
+	  Add some dummy events to the simple dummy driver.
+
+	  The purpose of this is to generate 'fake' event interrupts thus
+	  allowing that driver's code to be as close as possible to that
+	  a normal driver talking to hardware.
 
 config IIO_SIMPLE_DUMMY_BUFFER
 	bool "Buffered capture support"
@@ -32,6 +36,9 @@ config IIO_SIMPLE_DUMMY_BUFFER
 	help
 	  Add buffered data capture to the simple dummy driver.
 
+	  Buffer handling elements of industrial I/O reference driver.
+	  Uses the kfifo buffer.
+
 endif # IIO_SIMPLE_DUMMY
 
 endmenu
diff --git a/drivers/iio/gyro/hid-sensor-gyro-3d.c b/drivers/iio/gyro/hid-sensor-gyro-3d.c
index f59995a90387..36941e69f959 100644
--- a/drivers/iio/gyro/hid-sensor-gyro-3d.c
+++ b/drivers/iio/gyro/hid-sensor-gyro-3d.c
@@ -115,7 +115,7 @@ static int gyro_3d_read_raw(struct iio_dev *indio_dev,
 	*val = 0;
 	*val2 = 0;
 	switch (mask) {
-	case 0:
+	case IIO_CHAN_INFO_RAW:
 		hid_sensor_power_state(&gyro_state->common_attributes, true);
 		report_id = gyro_state->gyro[chan->scan_index].report_id;
 		address = gyro_3d_addresses[chan->scan_index];
diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index 93fd421b10d7..074e50657366 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -275,6 +275,16 @@ config LTR501
 	 This driver can also be built as a module.  If so, the module
          will be called ltr501.
 
+config LV0104CS
+	tristate "LV0104CS Ambient Light Sensor"
+	depends on I2C
+	help
+	 Say Y here if you want to build support for the On Semiconductor
+	 LV0104CS ambient light sensor.
+
+	 To compile this driver as a module, choose M here:
+	 the module will be called lv0104cs.
+
 config MAX44000
 	tristate "MAX44000 Ambient and Infrared Proximity Sensor"
 	depends on I2C
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index f714067a7816..f1777036d4f8 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_ISL29125)		+= isl29125.o
 obj-$(CONFIG_JSA1212)		+= jsa1212.o
 obj-$(CONFIG_SENSORS_LM3533)	+= lm3533-als.o
 obj-$(CONFIG_LTR501)		+= ltr501.o
+obj-$(CONFIG_LV0104CS)		+= lv0104cs.o
 obj-$(CONFIG_MAX44000)		+= max44000.o
 obj-$(CONFIG_OPT3001)		+= opt3001.o
 obj-$(CONFIG_PA12203001)	+= pa12203001.o
diff --git a/drivers/iio/light/cros_ec_light_prox.c b/drivers/iio/light/cros_ec_light_prox.c
index acfad4aeb27a..8e8a0e7f78d1 100644
--- a/drivers/iio/light/cros_ec_light_prox.c
+++ b/drivers/iio/light/cros_ec_light_prox.c
@@ -276,6 +276,7 @@ MODULE_DEVICE_TABLE(platform, cros_ec_light_prox_ids);
 static struct platform_driver cros_ec_light_prox_platform_driver = {
 	.driver = {
 		.name	= "cros-ec-light-prox",
+		.pm	= &cros_ec_sensors_pm_ops,
 	},
 	.probe		= cros_ec_light_prox_probe,
 	.id_table	= cros_ec_light_prox_ids,
diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
index befd693a4a31..406caaee9a3c 100644
--- a/drivers/iio/light/hid-sensor-als.c
+++ b/drivers/iio/light/hid-sensor-als.c
@@ -97,7 +97,7 @@ static int als_read_raw(struct iio_dev *indio_dev,
 	*val = 0;
 	*val2 = 0;
 	switch (mask) {
-	case 0:
+	case IIO_CHAN_INFO_RAW:
 		switch (chan->scan_index) {
 		case  CHANNEL_SCAN_INDEX_INTENSITY:
 		case  CHANNEL_SCAN_INDEX_ILLUM:
diff --git a/drivers/iio/light/lm3533-als.c b/drivers/iio/light/lm3533-als.c
index 36208a3652e9..ff5a3324b489 100644
--- a/drivers/iio/light/lm3533-als.c
+++ b/drivers/iio/light/lm3533-als.c
@@ -199,7 +199,7 @@ static int lm3533_als_read_raw(struct iio_dev *indio_dev,
 	int ret;
 
 	switch (mask) {
-	case 0:
+	case IIO_CHAN_INFO_RAW:
 		switch (chan->type) {
 		case IIO_LIGHT:
 			ret = lm3533_als_get_adc(indio_dev, false, val);
diff --git a/drivers/iio/light/lv0104cs.c b/drivers/iio/light/lv0104cs.c
new file mode 100644
index 000000000000..55b8e2855647
--- /dev/null
+++ b/drivers/iio/light/lv0104cs.c
@@ -0,0 +1,531 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * lv0104cs.c: LV0104CS Ambient Light Sensor Driver
+ *
+ * Copyright (C) 2018
+ * Author: Jeff LaBundy <jeff@labundy.com>
+ *
+ * 7-bit I2C slave address: 0x13
+ *
+ * Link to data sheet: http://www.onsemi.com/pub/Collateral/LV0104CS-D.PDF
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define LV0104CS_REGVAL_MEASURE		0xE0
+#define LV0104CS_REGVAL_SLEEP		0x00
+
+#define LV0104CS_SCALE_0_25X		0
+#define LV0104CS_SCALE_1X		1
+#define LV0104CS_SCALE_2X		2
+#define LV0104CS_SCALE_8X		3
+#define LV0104CS_SCALE_SHIFT		3
+
+#define LV0104CS_INTEG_12_5MS		0
+#define LV0104CS_INTEG_100MS		1
+#define LV0104CS_INTEG_200MS		2
+#define LV0104CS_INTEG_SHIFT		1
+
+#define LV0104CS_CALIBSCALE_UNITY	31
+
+struct lv0104cs_private {
+	struct i2c_client *client;
+	struct mutex lock;
+	u8 calibscale;
+	u8 scale;
+	u8 int_time;
+};
+
+struct lv0104cs_mapping {
+	int val;
+	int val2;
+	u8 regval;
+};
+
+static const struct lv0104cs_mapping lv0104cs_calibscales[] = {
+	{ 0, 666666, 0x81 },
+	{ 0, 800000, 0x82 },
+	{ 0, 857142, 0x83 },
+	{ 0, 888888, 0x84 },
+	{ 0, 909090, 0x85 },
+	{ 0, 923076, 0x86 },
+	{ 0, 933333, 0x87 },
+	{ 0, 941176, 0x88 },
+	{ 0, 947368, 0x89 },
+	{ 0, 952380, 0x8A },
+	{ 0, 956521, 0x8B },
+	{ 0, 960000, 0x8C },
+	{ 0, 962962, 0x8D },
+	{ 0, 965517, 0x8E },
+	{ 0, 967741, 0x8F },
+	{ 0, 969696, 0x90 },
+	{ 0, 971428, 0x91 },
+	{ 0, 972972, 0x92 },
+	{ 0, 974358, 0x93 },
+	{ 0, 975609, 0x94 },
+	{ 0, 976744, 0x95 },
+	{ 0, 977777, 0x96 },
+	{ 0, 978723, 0x97 },
+	{ 0, 979591, 0x98 },
+	{ 0, 980392, 0x99 },
+	{ 0, 981132, 0x9A },
+	{ 0, 981818, 0x9B },
+	{ 0, 982456, 0x9C },
+	{ 0, 983050, 0x9D },
+	{ 0, 983606, 0x9E },
+	{ 0, 984126, 0x9F },
+	{ 1, 0, 0x80 },
+	{ 1, 16129, 0xBF },
+	{ 1, 16666, 0xBE },
+	{ 1, 17241, 0xBD },
+	{ 1, 17857, 0xBC },
+	{ 1, 18518, 0xBB },
+	{ 1, 19230, 0xBA },
+	{ 1, 20000, 0xB9 },
+	{ 1, 20833, 0xB8 },
+	{ 1, 21739, 0xB7 },
+	{ 1, 22727, 0xB6 },
+	{ 1, 23809, 0xB5 },
+	{ 1, 24999, 0xB4 },
+	{ 1, 26315, 0xB3 },
+	{ 1, 27777, 0xB2 },
+	{ 1, 29411, 0xB1 },
+	{ 1, 31250, 0xB0 },
+	{ 1, 33333, 0xAF },
+	{ 1, 35714, 0xAE },
+	{ 1, 38461, 0xAD },
+	{ 1, 41666, 0xAC },
+	{ 1, 45454, 0xAB },
+	{ 1, 50000, 0xAA },
+	{ 1, 55555, 0xA9 },
+	{ 1, 62500, 0xA8 },
+	{ 1, 71428, 0xA7 },
+	{ 1, 83333, 0xA6 },
+	{ 1, 100000, 0xA5 },
+	{ 1, 125000, 0xA4 },
+	{ 1, 166666, 0xA3 },
+	{ 1, 250000, 0xA2 },
+	{ 1, 500000, 0xA1 },
+};
+
+static const struct lv0104cs_mapping lv0104cs_scales[] = {
+	{ 0, 250000, LV0104CS_SCALE_0_25X << LV0104CS_SCALE_SHIFT },
+	{ 1, 0, LV0104CS_SCALE_1X << LV0104CS_SCALE_SHIFT },
+	{ 2, 0, LV0104CS_SCALE_2X << LV0104CS_SCALE_SHIFT },
+	{ 8, 0, LV0104CS_SCALE_8X << LV0104CS_SCALE_SHIFT },
+};
+
+static const struct lv0104cs_mapping lv0104cs_int_times[] = {
+	{ 0, 12500, LV0104CS_INTEG_12_5MS << LV0104CS_INTEG_SHIFT },
+	{ 0, 100000, LV0104CS_INTEG_100MS << LV0104CS_INTEG_SHIFT },
+	{ 0, 200000, LV0104CS_INTEG_200MS << LV0104CS_INTEG_SHIFT },
+};
+
+static int lv0104cs_write_reg(struct i2c_client *client, u8 regval)
+{
+	int ret;
+
+	ret = i2c_master_send(client, (char *)&regval, sizeof(regval));
+	if (ret < 0)
+		return ret;
+	if (ret != sizeof(regval))
+		return -EIO;
+
+	return 0;
+}
+
+static int lv0104cs_read_adc(struct i2c_client *client, u16 *adc_output)
+{
+	__be16 regval;
+	int ret;
+
+	ret = i2c_master_recv(client, (char *)&regval, sizeof(regval));
+	if (ret < 0)
+		return ret;
+	if (ret != sizeof(regval))
+		return -EIO;
+
+	*adc_output = be16_to_cpu(regval);
+
+	return 0;
+}
+
+static int lv0104cs_get_lux(struct lv0104cs_private *lv0104cs,
+				int *val, int *val2)
+{
+	u8 regval = LV0104CS_REGVAL_MEASURE;
+	u16 adc_output;
+	int ret;
+
+	regval |= lv0104cs_scales[lv0104cs->scale].regval;
+	regval |= lv0104cs_int_times[lv0104cs->int_time].regval;
+	ret = lv0104cs_write_reg(lv0104cs->client, regval);
+	if (ret)
+		return ret;
+
+	/* wait for integration time to pass (with margin) */
+	switch (lv0104cs->int_time) {
+	case LV0104CS_INTEG_12_5MS:
+		msleep(50);
+		break;
+
+	case LV0104CS_INTEG_100MS:
+		msleep(150);
+		break;
+
+	case LV0104CS_INTEG_200MS:
+		msleep(250);
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	ret = lv0104cs_read_adc(lv0104cs->client, &adc_output);
+	if (ret)
+		return ret;
+
+	ret = lv0104cs_write_reg(lv0104cs->client, LV0104CS_REGVAL_SLEEP);
+	if (ret)
+		return ret;
+
+	/* convert ADC output to lux */
+	switch (lv0104cs->scale) {
+	case LV0104CS_SCALE_0_25X:
+		*val = adc_output * 4;
+		*val2 = 0;
+		return 0;
+
+	case LV0104CS_SCALE_1X:
+		*val = adc_output;
+		*val2 = 0;
+		return 0;
+
+	case LV0104CS_SCALE_2X:
+		*val = adc_output / 2;
+		*val2 = (adc_output % 2) * 500000;
+		return 0;
+
+	case LV0104CS_SCALE_8X:
+		*val = adc_output / 8;
+		*val2 = (adc_output % 8) * 125000;
+		return 0;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int lv0104cs_read_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *chan,
+				int *val, int *val2, long mask)
+{
+	struct lv0104cs_private *lv0104cs = iio_priv(indio_dev);
+	int ret;
+
+	if (chan->type != IIO_LIGHT)
+		return -EINVAL;
+
+	mutex_lock(&lv0104cs->lock);