[PATCH v2 1/3] iio: light: Add driver for ap3216c

[Robert Eshleman]

    This patch adds support for the ap3216c ambient light and proximity
    sensor.

    Supported features include:

    * Illuminance (lux)
    * Proximity (raw)
    * IR (raw)
    * Rising/falling threshold events for illuminance and proximity
    * Calibration scale for illuminance
    * Calibration bias for proximity

Signed-off-by: Robert Eshleman <bobbyeshleman@xxxxxxxxx>
---
Changes in v2:
- Add mutex protection in IRQ handler
- Support interrupt clearing for PS and ALS separately
- Mask away reserved bits when reading device registers
- Use regmap_bulk_read and regmap_bulk_write when possible
- Style cleanup

 drivers/iio/light/Kconfig   |  11 +
 drivers/iio/light/Makefile  |   1 +
 drivers/iio/light/ap3216c.c | 809 ++++++++++++++++++++++++++++++++++++
 3 files changed, 821 insertions(+)
 create mode 100644 drivers/iio/light/ap3216c.c

diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index 36f458433480..74688d19beb1 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -41,6 +41,17 @@ config AL3320A
 	 To compile this driver as a module, choose M here: the
 	 module will be called al3320a.
 
+config AP3216C
+	tristate "AP3216C Ambient Light and Proximity sensor"
+	select REGMAP_I2C
+	depends on I2C
+	help
+	  Say Y here to build a driver for the AP3216C Ambient Light and
+	  Proximity sensor.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ap3216c.
+
 config APDS9300
 	tristate "APDS9300 ambient light sensor"
 	depends on I2C
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index 286bf3975372..7d2f8fa0f30d 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -7,6 +7,7 @@
 obj-$(CONFIG_ACPI_ALS)		+= acpi-als.o
 obj-$(CONFIG_ADJD_S311)		+= adjd_s311.o
 obj-$(CONFIG_AL3320A)		+= al3320a.o
+obj-$(CONFIG_AP3216C)		+= ap3216c.o
 obj-$(CONFIG_APDS9300)		+= apds9300.o
 obj-$(CONFIG_APDS9960)		+= apds9960.o
 obj-$(CONFIG_BH1750)		+= bh1750.o
diff --git a/drivers/iio/light/ap3216c.c b/drivers/iio/light/ap3216c.c
new file mode 100644
index 000000000000..aaa319b932e6
--- /dev/null
+++ b/drivers/iio/light/ap3216c.c
@@ -0,0 +1,809 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AP3216C Ambient Light and Infrared Proximity Sensor
+ *
+ * Copyright (c) 2019, Robert Eshleman.
+ *
+ * Datasheet: https://pdf-datasheet-datasheet.netdna-ssl.com/pdf-down/A/P/3/AP3216C-LITE-ON.pdf
+ *
+ * 7-bit I2C slave address 0x1E
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/bits.h>
+#include <linux/regmap.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
+
+#define AP3216C_DRV_NAME "ap3216c"
+
+/* register addresses */
+#define AP3216C_SYS 0x0
+#define AP3216C_INT_STATUS 0x01
+#define AP3216C_INT_CLR 0x02
+#define AP3216C_IR_DATA_LO 0x0A
+#define AP3216C_IR_DATA_HI 0x0B
+#define AP3216C_ALS_DATA_LO 0x0C
+#define AP3216C_ALS_DATA_HI 0x0D
+#define AP3216C_PS_DATA_LO 0x0E
+#define AP3216C_PS_DATA_HI 0x0F
+#define AP3216C_ALS_CFG 0x10
+#define AP3216C_ALS_CALIB 0x19
+#define AP3216C_ALS_LO_THR_LO 0x1A
+#define AP3216C_ALS_LO_THR_HI 0x1B
+#define AP3216C_ALS_HI_THR_LO 0x1C
+#define AP3216C_ALS_HI_THR_HI 0x1D
+#define AP3216C_PS_CFG 0x20
+#define AP3216C_PS_CALIB_LO 0x28
+#define AP3216C_PS_CALIB_HI 0x29
+#define AP3216C_PS_LO_THR_LO 0x2A
+#define AP3216C_PS_LO_THR_HI 0x2B
+#define AP3216C_PS_HI_THR_LO 0x2C
+#define AP3216C_PS_HI_THR_HI 0x2D
+
+/* SYS_MODE mask and config value */
+#define AP3216C_SYS_MODE_ALS_PS 0x3
+
+/* INT_STATUS masks and config value */
+#define AP3216C_INT_STATUS_ALS_MASK BIT(0)
+#define AP3216C_INT_STATUS_PS_MASK BIT(1)
+#define AP3216C_INT_STATUS_CLR GENMASK(1, 0)
+#define AP3216C_INT_ALS_CLR BIT(0)
+#define AP3216C_INT_PS_CLR BIT(1)
+#define AP3216C_INT_CLR_MANUAL 1
+
+/* IR_DATA mask/shift */
+#define AP3216C_IR_DATA_LO_MASK GENMASK(1, 0)
+#define AP3216C_IR_DATA_HI_SHIFT 2
+
+/* ALS_DATA shift and fractional helper */
+#define AP3216C_ALS_DATA_HI_SHIFT 8
+#define AP3216C_ALS_DATA_DENOM 100000
+
+/* ALS_CALIB masks/shifts */
+#define AP3216C_ALS_CALIB_INT_MASK GENMASK(7, 6)
+#define AP3216C_ALS_CALIB_INT_SHIFT 6
+#define AP3216C_ALS_CALIB_DEC_MASK GENMASK(5, 0)
+
+/* PS_DATA shifts/masks/bits */
+#define AP3216C_PS_DATA_LO_MASK GENMASK(3, 0)
+#define AP3216C_PS_DATA_LO_IR_OF BIT(6)
+#define AP3216C_PS_DATA_HI_MASK GENMASK(5, 0)
+#define AP3216C_PS_DATA_HI_SHIFT 4
+#define AP3216C_PS_DATA_HI_IR_OF BIT(6)
+
+/* ALS_CFG masks */
+#define AP3216C_ALS_CFG_GAIN_MASK GENMASK(5, 4)
+#define AP3216C_ALS_CFG_GAIN_SHIFT 4
+
+/* ALS_CALIB shifts */
+#define AP3216C_ALS_CALIB_INT_SHIFT 6
+
+/* ALS_HI_THR masks and shifts */
+#define AP3216C_ALS_HI_THR_LO_MASK GENMASK(7, 0)
+#define AP3216C_ALS_HI_THR_HI_SHIFT 8
+#define AP3216C_ALS_HI_THR_HI_MASK GENMASK(16, 8)
+#define AP3216C_ALS_HI_THR_HI_READ_MASK GENMASK(7, 0)
+#define AP3216C_ALS_HI_THR_HI_SHIFT 8
+
+#define AP3216C_ALS_THR_HI_SHIFT 8
+
+/* ALS_LO_THR masks and shifts */
+#define AP3216C_ALS_LO_THR_LO_MASK GENMASK(7, 0)
+#define AP3216C_ALS_LO_THR_HI_MASK GENMASK(16, 8)
+#define AP3216C_ALS_LO_THR_HI_SHIFT 8
+
+/* PS_CFG reg mask/shift/bit values */
+#define AP3216C_PS_CFG_GAIN_MASK GENMASK(3, 2)
+#define AP3216C_PS_CFG_GAIN_SHIFT 2
+#define AP3216C_PS_CFG_GAIN(val) \
+	(1 << ((val & AP3216C_PS_CFG_GAIN_MASK) >> AP3216C_PS_CFG_GAIN_SHIFT))
+
+/* PS_LO and PS_HI multiplier values */
+#define AP3216C_PS_LO_THR_HI_MULT 4
+#define AP3216C_PS_HI_THR_HI_MULT 4
+#define AP3216C_PS_THR_HI_MULT 4
+
+/* PS_THR_LO and PS_THR_HI masks/shifts */
+#define AP3216C_PS_THR_LO_MASK GENMASK(1, 0)
+#define AP3216C_PS_THR_HI_MASK GENMASK(10, 2)
+#define AP3216C_PS_THR_HI_SHIFT 2
+
+/* PS_CALIB_HI and PS_CALIB_LO shift/mask/bit values */
+#define AP3216C_PS_CALIB_HI_SHIFT 1
+#define AP3216C_PS_CALIB_HI_MASK GENMASK(8, 1)
+#define AP3216C_PS_CALIB_LO_MASK BIT(0)
+
+/* ALS fractional helper values */
+#define AP3216C_ALS_INTEG_MULT 1000
+#define AP3216C_ALS_FRACT_DIV 100
+
+/* ALS_CALIB min/max values (0.0 <= ALS_CALIB <= 3.984375) */
+#define AP3216C_ALS_CALIB_INT_MIN 0
+#define AP3216C_ALS_CALIB_DEC_MIN 0
+#define AP3216C_ALS_CALIB_INT_MAX 3
+#define AP3216C_ALS_CALIB_DEC_MAX 984375
+
+/* ALS_CALIB conversion denominator */
+#define AP3216C_ALS_CALIB_DENOM 64
+
+#define AP3216C_IIO_MULT 1000000
+#define AP3216C_PS_THR_MAX (BIT(10) - 1)
+
+/* See ALS configuration ALS_GAIN field in datasheet */
+#define AP3216C_ALS_THR_MAX 20661
+
+static const u16 ap3216c_gain_array[] = {
+	3500,  /* 0.3500 lux resolution */
+	 788,  /* 0.0788 lux resolution */
+	 197,  /* 0.0197 lux resolution */
+	  49,  /* 0.0049 lux resolution */
+};
+
+static const u16 ap3216c_als_max_thr_array[] = {
+	20661,  /* max thr when gain is 0.3500 */
+	 5162,  /* max thr when gain is 0.0788 */
+	 1291,  /* max thr when gain is 0.0197 */
+	  323,  /* max thr when gain is 0.0049*/
+};
+
+struct ap3216c_data {
+	struct regmap *regmap;
+	struct i2c_client *client;
+	struct mutex lock;
+	bool als_thresh_en;
+	bool prox_thresh_en;
+};
+
+static const struct iio_event_spec ap3216c_event_spec[] = {
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_RISING,
+		.mask_separate = BIT(IIO_EV_INFO_VALUE),
+	},
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_FALLING,
+		.mask_separate = BIT(IIO_EV_INFO_VALUE),
+	},
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_EITHER,
+		.mask_shared_by_type = BIT(IIO_EV_INFO_ENABLE),
+	},
+};
+
+static const struct iio_chan_spec ap3216c_channels[] = {
+	{
+		.type = IIO_LIGHT,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+				      BIT(IIO_CHAN_INFO_CALIBSCALE),
+		.event_spec = ap3216c_event_spec,
+		.num_event_specs = ARRAY_SIZE(ap3216c_event_spec),
+	},
+	{
+		.type = IIO_PROXIMITY,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_CALIBBIAS),
+		.event_spec = ap3216c_event_spec,
+		.num_event_specs = ARRAY_SIZE(ap3216c_event_spec),
+	},
+	{
+		.type = IIO_LIGHT,
+		.modified = 1,
+		.channel2 = IIO_MOD_LIGHT_IR,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+	}
+};
+
+static int ap3216c_read_gain(struct ap3216c_data *data, u16 *gain)
+{
+	unsigned int cfg;
+	int ret;
+
+	ret = regmap_read(data->regmap, AP3216C_ALS_CFG, &cfg);
+	if (ret < 0)
+		return ret;
+
+	*gain = ap3216c_gain_array[(cfg & AP3216C_ALS_CFG_GAIN_MASK) >>
+				    AP3216C_ALS_CFG_GAIN_SHIFT];
+	return 0;
+}
+
+static int ap3216c_read_max_thr(struct ap3216c_data *data, u16 *max_thr)
+{
+	unsigned int cfg;
+	int ret;
+
+	ret = regmap_read(data->regmap, AP3216C_ALS_CFG, &cfg);
+	if (ret < 0)
+		return ret;
+
+	/* max thr is derived from the gain bits of ALS_CFG */
+	*max_thr = ap3216c_als_max_thr_array[
+			(cfg & AP3216C_ALS_CFG_GAIN_MASK) >>
+			 AP3216C_ALS_CFG_GAIN_SHIFT];
+	return 0;
+}
+
+static int ap3216c_write_event_value(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     enum iio_event_type type,
+				     enum iio_event_direction dir,
+				     enum iio_event_info info,
+				     int val, int val2)
+{
+	struct ap3216c_data *data = iio_priv(indio_dev);
+	u8 vals[2];
+	int integral, fractional;
+	u16 thr, max_thr, gain;
+	int ret;
+
+	if (val < 0 || val2 < 0)
+		return -EINVAL;
+
+	switch (chan->type) {
+	case IIO_LIGHT:
+		ret = ap3216c_read_max_thr(data, &max_thr);
+		if (ret < 0)
+			return ret;
+
+		if (val > max_thr)
+			val = max_thr;
+
+		ret = ap3216c_read_gain(data, &gain);
+		if (ret < 0)
+			return ret;
+
+		integral = val * AP3216C_ALS_INTEG_MULT / gain;
+		fractional = val2 / AP3216C_ALS_FRACT_DIV / gain;
+
+		thr = integral + fractional;
+
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			vals[0] = thr & AP3216C_ALS_HI_THR_LO_MASK;
+			vals[1] = (thr & AP3216C_ALS_HI_THR_HI_MASK) >>
+				   AP3216C_ALS_HI_THR_HI_SHIFT;
+
+			return regmap_bulk_write(data->regmap,
+						 AP3216C_ALS_HI_THR_LO,
+						 vals, 2);
+
+		case IIO_EV_DIR_FALLING:
+			vals[0] = thr & AP3216C_ALS_LO_THR_LO_MASK;
+			vals[1] = (thr & AP3216C_ALS_LO_THR_HI_MASK) >>
+				   AP3216C_ALS_LO_THR_HI_SHIFT;
+
+			return regmap_bulk_write(data->regmap,
+						 AP3216C_ALS_LO_THR_LO,
+						 vals, 2);
+		default:
+			return -EINVAL;
+		}
+
+
+	case IIO_PROXIMITY:
+		if (val > AP3216C_PS_THR_MAX)
+			val = AP3216C_PS_THR_MAX;
+
+		vals[0] = val & AP3216C_PS_THR_LO_MASK;
+		vals[1] = (val & AP3216C_PS_THR_HI_MASK) >>
+			   AP3216C_PS_THR_HI_SHIFT;
+
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			return regmap_bulk_write(data->regmap,
+						 AP3216C_PS_HI_THR_LO,
+						 vals, 2);
+
+		case IIO_EV_DIR_FALLING:
+			return regmap_bulk_write(data->regmap,
+						 AP3216C_PS_LO_THR_LO,
+						 vals, 2);
+		default:
+			return -EINVAL;
+		}
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int ap3216c_get_als_reg(enum iio_event_direction dir)
+{
+	switch (dir) {
+	case IIO_EV_DIR_RISING:
+		return AP3216C_ALS_HI_THR_LO;
+
+	case IIO_EV_DIR_FALLING:
+		return AP3216C_ALS_LO_THR_LO;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int ap3216c_get_ps_reg(enum iio_event_direction dir)
+{
+	switch (dir) {
+	case IIO_EV_DIR_RISING:
+		return AP3216C_PS_HI_THR_LO;
+
+	case IIO_EV_DIR_FALLING:
+		return AP3216C_PS_LO_THR_LO;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int ap3216c_read_event_value(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     enum iio_event_type type,
+				     enum iio_event_direction dir,
+				     enum iio_event_info info,
+				     int *val, int *val2)
+{
+	struct ap3216c_data *data = iio_priv(indio_dev);
+	u16 gain;
+	u8 vals[2];
+	int reg, ret;
+
+	switch (chan->type) {
+	case IIO_LIGHT:
+		reg = ap3216c_get_als_reg(dir);
+		if (reg < 0)
+			return reg;
+
+		ret = regmap_bulk_read(data->regmap, reg, vals, 2);
+		if (ret < 0)
+			return ret;
+
+		ret = ap3216c_read_gain(data, &gain);
+		if (ret < 0)
+			return ret;
+
+		*val = ((vals[1] << AP3216C_ALS_THR_HI_SHIFT) | vals[0]) *
+			 gain / AP3216C_ALS_INTEG_MULT;
+		return IIO_VAL_INT;
+
+	case IIO_PROXIMITY:
+		reg = ap3216c_get_ps_reg(dir);
+		if (reg < 0)
+			return reg;
+
+		ret = regmap_bulk_read(data->regmap, reg, vals, 2);
+		if (ret < 0)
+			return ret;
+
+		*val = (vals[1] << 2) | (vals[0] & AP3216C_PS_THR_LO_MASK);
+
+		return IIO_VAL_INT;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int ap3216c_read_event_config(struct iio_dev *indio_dev,
+				    const struct iio_chan_spec *chan,
+				    enum iio_event_type type,
+				    enum iio_event_direction dir)
+{
+	struct ap3216c_data *data = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&data->lock);
+	switch (chan->type) {
+	case IIO_LIGHT:
+		ret = data->als_thresh_en;
+		break;
+
+	case IIO_PROXIMITY:
+		ret = data->prox_thresh_en;
+		break;
+
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int ap3216c_write_event_config(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     enum iio_event_type type,
+				     enum iio_event_direction dir, int state)
+{
+	struct ap3216c_data *data = iio_priv(indio_dev);
+	int ret = 0;
+
+	mutex_lock(&data->lock);
+	switch (chan->type) {
+	case IIO_LIGHT:
+		data->als_thresh_en = state;
+		break;
+
+	case IIO_PROXIMITY:
+		data->prox_thresh_en = state;
+		break;
+
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static const struct regmap_config ap3216c_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = AP3216C_PS_HI_THR_HI,
+};
+
+/**
+ * Returns integral part of decimal between 0.0 and 3.984275
+ */
+static int ap3216c_als_calibscale_int(int val)
+{
+	if (val > AP3216C_ALS_CALIB_INT_MAX)
+		return AP3216C_ALS_CALIB_INT_MAX;
+
+	if (val <= AP3216C_ALS_CALIB_INT_MIN)
+		return AP3216C_ALS_CALIB_INT_MIN;
+
+	return val;
+}
+
+/**
+ * Returns decimal part of decimal number between 0.0 and 3.984275
+ */
+static int ap3216c_als_calibscale_dec(int val, int val2)
+{
+	/* Return max decimal if number exceeds calibscale max */
+	if (val > AP3216C_ALS_CALIB_INT_MAX ||
+	    (val == AP3216C_ALS_CALIB_INT_MAX &&
+	     val2 > AP3216C_ALS_CALIB_DEC_MAX))
+		return AP3216C_ALS_CALIB_DEC_MAX;
+
+	/* Floor the decimal if integral below minimum */
+	if (val <= AP3216C_ALS_CALIB_INT_MIN)
+		return AP3216C_ALS_CALIB_DEC_MIN;
+
+	/* Floor the decimal if decimal below minimum */
+	if (val2 < AP3216C_ALS_CALIB_DEC_MIN)
+		return AP3216C_ALS_CALIB_DEC_MIN;
+
+	/* Return max decimal if decimal above maximum */
+	if (val2 > AP3216C_ALS_CALIB_DEC_MAX)
+		return AP3216C_ALS_CALIB_DEC_MAX;
+
+	return val2;
+}
+
+static int ap3216c_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int val, int val2, long mask)
+{
+	struct ap3216c_data *data = iio_priv(indio_dev);
+	int integral, decimal;
+	u8 vals[2];
+	int tmp;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_CALIBSCALE:
+		switch (chan->type) {
+		case IIO_LIGHT:
+			integral = ap3216c_als_calibscale_int(val);
+			decimal = ap3216c_als_calibscale_dec(val, val2);
+
+			tmp = integral << AP3216C_ALS_CALIB_INT_SHIFT;
+
+			/*
+			 * Reverse scaling by multiplying by the scaling
+			 * denominator and dividing by IIO multiplier.
+			 */
+			tmp |= (decimal * AP3216C_ALS_CALIB_DENOM) /
+				AP3216C_IIO_MULT;
+
+			return regmap_write(data->regmap,
+					    AP3216C_ALS_CALIB, tmp);
+
+		default:
+			return -EINVAL;
+		}
+
+	case IIO_CHAN_INFO_CALIBBIAS:
+		switch (chan->type) {
+		case IIO_PROXIMITY:
+			vals[0] = val & AP3216C_PS_CALIB_LO_MASK;
+			vals[1] = (val & AP3216C_PS_CALIB_HI_MASK) >>
+				   AP3216C_PS_CALIB_HI_SHIFT;
+
+			return regmap_bulk_write(data->regmap,
+						 AP3216C_PS_CALIB_LO,
+						 vals, 2);
+
+		default:
+			return -EINVAL;
+		}
+	default:
+		return -EINVAL;
+	}
+}
+
+static int ap3216c_read_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *chan,
+				int *val, int *val2, long mask)
+{
+	struct ap3216c_data *data = iio_priv(indio_dev);
+	u16 gain;
+	u8 vals[2];
+	int cfg, tmp;
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_CALIBSCALE:
+		switch (chan->type) {
+		case IIO_LIGHT:
+			ret = regmap_read(data->regmap,
+					  AP3216C_ALS_CALIB, &tmp);
+			if (ret < 0)
+				return ret;
+
+			/* Scale is multiplied by 1/64 */
+			*val = tmp;
+			*val2 = AP3216C_ALS_CALIB_DENOM;
+
+			return IIO_VAL_FRACTIONAL;
+
+		default:
+			return -EINVAL;
+		}
+
+	case IIO_CHAN_INFO_CALIBBIAS:
+		switch (chan->type) {
+		case IIO_PROXIMITY:
+			ret = regmap_bulk_read(data->regmap,
+					       AP3216C_PS_CALIB_LO,
+					       vals, 2);
+			if (ret < 0)
+				return ret;
+
+			*val = (vals[0] & AP3216C_PS_CALIB_LO_MASK) |
+			       ((vals[1] & AP3216C_PS_CALIB_HI_MASK) <<
+				AP3216C_PS_CALIB_HI_SHIFT);
+
+			return IIO_VAL_INT;
+
+		default:
+			return -EINVAL;
+		}
+
+	case IIO_CHAN_INFO_PROCESSED:
+		switch (chan->type) {
+		case IIO_LIGHT:
+			ret = regmap_bulk_read(data->regmap,
+					       AP3216C_ALS_DATA_LO,
+					       vals, 2);
+			if (ret < 0)
+				return ret;
+
+			ret = ap3216c_read_gain(data, &gain);
+			if (ret < 0)
+				return ret;
+
+			*val = ((vals[1] << AP3216C_ALS_DATA_HI_SHIFT) |
+				 vals[0]) * gain;
+			*val2 = AP3216C_ALS_DATA_DENOM;
+
+			return IIO_VAL_FRACTIONAL;
+
+		default:
+			return -EINVAL;
+		}
+
+	case IIO_CHAN_INFO_RAW:
+		switch (chan->type) {
+		case IIO_LIGHT:
+			if (chan->channel2 != IIO_MOD_LIGHT_IR)
+				return -EINVAL;
+
+			ret = regmap_bulk_read(data->regmap,
+					       AP3216C_IR_DATA_LO,
+					       vals, 2);
+
+			*val = (vals[0] & AP3216C_IR_DATA_LO_MASK) |
+			       (vals[1] << AP3216C_IR_DATA_HI_SHIFT);
+
+
+			return IIO_VAL_INT;
+
+		case IIO_PROXIMITY:
+			ret = regmap_bulk_read(data->regmap,
+					       AP3216C_PS_DATA_LO,
+					       vals, 2);
+			if (ret < 0)
+				return ret;
+
+			ret = regmap_read(data->regmap,
+					  AP3216C_PS_CFG, &cfg);
+			if (ret < 0)
+				return ret;
+
+			tmp = vals[0] & AP3216C_PS_DATA_LO_MASK;
+			tmp |= (vals[1] & AP3216C_PS_DATA_HI_MASK) <<
+				AP3216C_PS_DATA_HI_SHIFT;
+			*val = tmp * AP3216C_PS_CFG_GAIN(cfg);
+
+			return IIO_VAL_INT;
+
+		default:
+			return -EINVAL;
+		}
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_info ap3216c_info = {
+	.read_raw = ap3216c_read_raw,
+	.write_raw = ap3216c_write_raw,
+	.read_event_value = ap3216c_read_event_value,
+	.write_event_value = ap3216c_write_event_value,
+	.read_event_config = ap3216c_read_event_config,
+	.write_event_config = ap3216c_write_event_config,
+};
+
+static irqreturn_t ap3216c_event_handler(int irq, void *p)
+{
+	struct iio_dev *indio_dev = p;
+	struct ap3216c_data *data = iio_priv(indio_dev);
+	int status;
+	s64 timestamp;
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = regmap_read(data->regmap, AP3216C_INT_STATUS, &status);
+	if (ret) {
+		dev_err(&data->client->dev, "error reading IRQ status\n");
+		goto done;
+	}
+
+	/* The IRQ was not from this device */
+	if (!status) {
+		mutex_unlock(&data->lock);
+		return IRQ_NONE;
+	}
+
+	timestamp = iio_get_time_ns(indio_dev);
+	if (status & AP3216C_INT_STATUS_PS_MASK) {
+		if (data->prox_thresh_en)
+			iio_push_event(indio_dev,
+				       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 0,
+							    IIO_EV_TYPE_THRESH,
+							    IIO_EV_DIR_EITHER),
+				       timestamp);
+
+		ret = regmap_write(data->regmap,
+				   AP3216C_INT_STATUS, AP3216C_INT_PS_CLR);
+		if (ret < 0)
+			dev_err(&data->client->dev, "error clearing PS interrupt\n");
+	}
+
+	if (status & AP3216C_INT_STATUS_ALS_MASK) {
+		if (data->als_thresh_en)
+			iio_push_event(indio_dev,
+				       IIO_UNMOD_EVENT_CODE(IIO_LIGHT, 0,
+							    IIO_EV_TYPE_THRESH,
+							    IIO_EV_DIR_EITHER),
+				       timestamp);
+
+		ret = regmap_write(data->regmap,
+				   AP3216C_INT_STATUS, AP3216C_INT_ALS_CLR);
+		if (ret < 0)
+			dev_err(&data->client->dev, "error clearing ALS interrupt\n");
+	}
+
+done:
+	mutex_unlock(&data->lock);
+	return IRQ_HANDLED;
+}
+
+static int ap3216c_probe(struct i2c_client *client,
+			  const struct i2c_device_id *id)
+{
+	struct ap3216c_data *data;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	data->client = client;
+	mutex_init(&data->lock);
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &ap3216c_info;
+	indio_dev->name = AP3216C_DRV_NAME;
+	indio_dev->channels = ap3216c_channels;
+	indio_dev->num_channels = ARRAY_SIZE(ap3216c_channels);
+
+	data->regmap = devm_regmap_init_i2c(client, &ap3216c_regmap_config);
+	if (IS_ERR(data->regmap)) {
+		dev_err(&client->dev, "Failed to allocate register map\n");
+		return PTR_ERR(data->regmap);
+	}
+
+	/* Default to thresh events disabled */
+	data->als_thresh_en = false;
+	data->prox_thresh_en = false;
+
+	/*
+	 * Require that that the interrupt is cleared only when the INT_STATUS
+	 * register is written to, instead of when data is read.
+	 */
+	ret = regmap_write(data->regmap,
+			   AP3216C_INT_CLR, AP3216C_INT_CLR_MANUAL);
+	if (ret < 0)
+		return ret;
+
+	ret = regmap_write(data->regmap, AP3216C_INT_STATUS,
+			   AP3216C_INT_PS_CLR | AP3216C_INT_ALS_CLR);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "error clearing interrupts\n");
+		return ret;
+	}
+
+	if (client->irq) {
+		ret = devm_request_threaded_irq(&client->dev, client->irq,
+						NULL, ap3216c_event_handler,
+						IRQF_TRIGGER_FALLING |
+						IRQF_SHARED | IRQF_ONESHOT,
+						client->name, indio_dev);
+		if (ret)
+			return ret;
+	}
+
+	/* Enable ALS and PS+IR */
+	ret = regmap_write(data->regmap, AP3216C_SYS, AP3216C_SYS_MODE_ALS_PS);
+	if (ret < 0)
+		return ret;
+
+	return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+static const struct of_device_id ap3216c_of_match[] = {
+	{ .compatible = "liteon,ap3216c", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, ap3216c_of_match);
+
+static const struct i2c_device_id ap3216c_id[] = {
+	{"ap3216c", 0},
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, ap3216c_id);
+
+static struct i2c_driver ap3216c_driver = {
+	.driver = {
+		.name	= AP3216C_DRV_NAME,
+	},
+	.probe		= ap3216c_probe,
+	.id_table	= ap3216c_id,
+};
+module_i2c_driver(ap3216c_driver);
+
+MODULE_AUTHOR("Robert Eshleman <bobbyeshleman@xxxxxxxxx>");
+MODULE_DESCRIPTION("AP3216C Ambient Light and Proximity Sensor");
+MODULE_LICENSE("GPL v2");
-- 
2.20.1