[PATCH 1/1] iio: vcnl4000: Add IR current adjust support

[Pratik Prajapati <pratik.prajapati12@gmail.com>]

Signed-off-by: Pratik Prajapati <pratik.prajapati12@gmail.com>
---
 drivers/iio/light/vcnl4000.c | 119 +++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 116 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
index c9d85bb..6b8b223 100644
--- a/drivers/iio/light/vcnl4000.c
+++ b/drivers/iio/light/vcnl4000.c
@@ -11,7 +11,6 @@
  * IIO driver for VCNL4000 (7-bit I2C slave address 0x13)
  *
  * TODO:
- *   allow to adjust IR current
  *   proximity threshold and event handling
  */
 
@@ -19,6 +18,7 @@
 #include <linux/i2c.h>
 #include <linux/err.h>
 #include <linux/delay.h>
+#include <linux/regmap.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
@@ -42,8 +42,14 @@
 #define VCNL4000_AL_OD		0x10 /* start on-demand ALS measurement */
 #define VCNL4000_PS_OD		0x08 /* start on-demand proximity measurement */
 
+/* Bit mask for LED_CURRENT register */
+#define VCNL4000_LED_CURRENT_MASK	0x3F
+#define VCNL4000_LED_CURRENT_MAX	20
+
 struct vcnl4000_data {
 	struct i2c_client *client;
+	struct mutex lock;
+	struct regmap *regmap;
 };
 
 static const struct i2c_device_id vcnl4000_id[] = {
@@ -98,9 +104,36 @@ static const struct iio_chan_spec vcnl4000_channels[] = {
 	}, {
 		.type = IIO_PROXIMITY,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+	}, {
+		.type = IIO_CURRENT,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+			BIT(IIO_CHAN_INFO_SCALE),
+		.extend_name = "led",
+		.output = 1,
+		.scan_index = -1,
 	}
 };
 
+static int vcnl4000_write_led_current_raw(struct vcnl4000_data *data, int val)
+{
+	if (val < 0 || val > VCNL4000_LED_CURRENT_MAX)
+		return -ERANGE;
+	return regmap_write_bits(data->regmap, VCNL4000_LED_CURRENT,
+		VCNL4000_LED_CURRENT_MASK, val);
+}
+
+static int vcnl4000_read_led_current_raw(struct vcnl4000_data *data)
+{
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_read(data->regmap, VCNL4000_LED_CURRENT, &regval);
+	if (ret < 0)
+		return ret;
+	regval &= VCNL4000_LED_CURRENT_MASK;
+	return regval;
+}
+
 static int vcnl4000_read_raw(struct iio_dev *indio_dev,
 				struct iio_chan_spec const *chan,
 				int *val, int *val2, long mask)
@@ -127,15 +160,31 @@ static int vcnl4000_read_raw(struct iio_dev *indio_dev,
 				return ret;
 			ret = IIO_VAL_INT;
 			break;
+		case IIO_CURRENT:
+			mutex_lock(&data->lock);
+			ret = vcnl4000_read_led_current_raw(data);
+			mutex_unlock(&data->lock);
+			if (ret < 0)
+				return ret;
+			*val = ret;
+			return IIO_VAL_INT;
 		default:
 			break;
 		}
 		break;
+
 	case IIO_CHAN_INFO_SCALE:
-		if (chan->type == IIO_LIGHT) {
+		switch (chan->type) {
+		case IIO_LIGHT:
 			*val = 0;
 			*val2 = 250000;
-			ret = IIO_VAL_INT_PLUS_MICRO;
+			return IIO_VAL_INT_PLUS_MICRO;
+		case IIO_CURRENT:
+			/* Output register is in 10s of miliamps */
+			*val = 10;
+			return IIO_VAL_INT;
+		default:
+			break;
 		}
 		break;
 	default:
@@ -145,11 +194,69 @@ static int vcnl4000_read_raw(struct iio_dev *indio_dev,
 	return ret;
 }
 
+static int vcnl4000_write_raw(struct iio_dev *indio_dev,
+					struct iio_chan_spec const *chan,
+					int val, int val2, long mask)
+{
+	struct vcnl4000_data *data = iio_priv(indio_dev);
+	int ret;
+
+	if (mask == IIO_CHAN_INFO_RAW && chan->type == IIO_CURRENT) {
+		mutex_lock(&data->lock);
+		ret = vcnl4000_write_led_current_raw(data, val);
+		mutex_unlock(&data->lock);
+		return ret;
+	}
+	return -EINVAL;
+}
+
 static const struct iio_info vcnl4000_info = {
 	.read_raw = vcnl4000_read_raw,
+	.write_raw = vcnl4000_write_raw,
 	.driver_module = THIS_MODULE,
 };
 
+static bool vcnl4000_readable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case VCNL4000_COMMAND:
+	case VCNL4000_PROD_REV:
+	case VCNL4000_LED_CURRENT:
+	case VCNL4000_AL_PARAM:
+	case VCNL4000_AL_RESULT_HI:
+	case VCNL4000_AL_RESULT_LO:
+	case VCNL4000_PS_RESULT_HI:
+	case VCNL4000_PS_RESULT_LO:
+	case VCNL4000_PS_MEAS_FREQ:
+	case VCNL4000_PS_MOD_ADJ:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool vcnl4000_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case VCNL4000_COMMAND:
+	case VCNL4000_LED_CURRENT:
+	case VCNL4000_AL_PARAM:
+	case VCNL4000_PS_MEAS_FREQ:
+	case VCNL4000_PS_MOD_ADJ:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static const struct regmap_config vcnl4000_regmap_config = {
+	.reg_bits	= 8,
+	.val_bits	= 8,
+	.max_register	= VCNL4000_PS_MOD_ADJ,
+	.readable_reg	= vcnl4000_readable_reg,
+	.writeable_reg	= vcnl4000_writeable_reg,
+};
+
 static int vcnl4000_probe(struct i2c_client *client,
 			  const struct i2c_device_id *id)
 {
@@ -162,7 +269,13 @@ static int vcnl4000_probe(struct i2c_client *client,
 		return -ENOMEM;
 
 	data = iio_priv(indio_dev);
+	data->regmap = devm_regmap_init_i2c(client, &vcnl4000_regmap_config);
+	if (IS_ERR(data->regmap)) {
+		dev_err(&client->dev, "regmap_init failed!\n");
+		return PTR_ERR(data->regmap);
+	}
 	i2c_set_clientdata(client, indio_dev);
+	mutex_init(&data->lock);
 	data->client = client;
 
 	ret = i2c_smbus_read_byte_data(data->client, VCNL4000_PROD_REV);
-- 
2.6.2