1 files changed, 161 insertions, 42 deletions

diff --git a/drivers/iio/light/veml6070.c b/drivers/iio/light/veml6070.c
index d99bf3ae0fe8..6d4483c85f30 100644
--- a/drivers/iio/light/veml6070.c
+++ b/drivers/iio/light/veml6070.c
@@ -6,14 +6,16 @@
  *
  * IIO driver for VEML6070 (7-bit I2C slave addresses 0x38 and 0x39)
  *
- * TODO: integration time, ACK signal
+ * TODO: ACK signal
  */
 
+#include <linux/bitfield.h>
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/mutex.h>
 #include <linux/err.h>
 #include <linux/delay.h>
+#include <linux/units.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
@@ -28,50 +30,113 @@
 #define VEML6070_COMMAND_RSRVD	BIT(1) /* reserved, set to 1 */
 #define VEML6070_COMMAND_SD	BIT(0) /* shutdown mode when set */
 
-#define VEML6070_IT_10	0x04 /* integration time 1x */
+#define VEML6070_IT_05		0x00
+#define VEML6070_IT_10		0x01
+#define VEML6070_IT_20		0x02
+#define VEML6070_IT_40		0x03
+
+#define VEML6070_MIN_RSET_KOHM	75
+#define VEML6070_MIN_IT_US	15625 /* Rset = 75 kohm, IT = 1/2 */
 
 struct veml6070_data {
 	struct i2c_client *client1;
 	struct i2c_client *client2;
 	u8 config;
 	struct mutex lock;
+	u32 rset;
+	int it[4][2];
 };
 
+static int veml6070_calc_it(struct device *dev, struct veml6070_data *data)
+{
+	int i, tmp_it;
+
+	data->rset = 270000;
+	device_property_read_u32(dev, "vishay,rset-ohms", &data->rset);
+
+	if (data->rset < 75000 || data->rset > 1200000)
+		return dev_err_probe(dev, -EINVAL, "Rset out of range\n");
+
+	/*
+	 * convert to kohm to avoid overflows and work with the same units as
+	 * in the datasheet and simplify UVI operations.
+	 */
+	data->rset /= KILO;
+
+	tmp_it = VEML6070_MIN_IT_US * data->rset / VEML6070_MIN_RSET_KOHM;
+	for (i = 0; i < ARRAY_SIZE(data->it); i++) {
+		data->it[i][0] = (tmp_it << i) / MICRO;
+		data->it[i][1] = (tmp_it << i) % MICRO;
+	}
+
+	return 0;
+}
+
+static int veml6070_get_it(struct veml6070_data *data, int *val, int *val2)
+{
+	int it_idx = FIELD_GET(VEML6070_COMMAND_IT, data->config);
+
+	*val = data->it[it_idx][0];
+	*val2 = data->it[it_idx][1];
+
+	return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int veml6070_set_it(struct veml6070_data *data, int val, int val2)
+{
+	int it_idx;
+
+	for (it_idx = 0; it_idx < ARRAY_SIZE(data->it); it_idx++) {
+		if (data->it[it_idx][0] == val && data->it[it_idx][1] == val2)
+			break;
+	}
+
+	if (it_idx >= ARRAY_SIZE(data->it))
+		return -EINVAL;
+
+	data->config = (data->config & ~VEML6070_COMMAND_IT) |
+		FIELD_PREP(VEML6070_COMMAND_IT, it_idx);
+
+	return i2c_smbus_write_byte(data->client1, data->config);
+}
+
 static int veml6070_read(struct veml6070_data *data)
 {
-	int ret;
+	int ret, it_ms, val, val2;
 	u8 msb, lsb;
 
-	mutex_lock(&data->lock);
+	guard(mutex)(&data->lock);
 
 	/* disable shutdown */
 	ret = i2c_smbus_write_byte(data->client1,
 	    data->config & ~VEML6070_COMMAND_SD);
 	if (ret < 0)
-		goto out;
+		return ret;
 
-	msleep(125 + 10); /* measurement takes up to 125 ms for IT 1x */
+	veml6070_get_it(data, &val, &val2);
+	it_ms = val * MILLI + val2 / (MICRO / MILLI);
+	msleep(it_ms + 10);
 
 	ret = i2c_smbus_read_byte(data->client2); /* read MSB, address 0x39 */
 	if (ret < 0)
-		goto out;
+		return ret;
+
 	msb = ret;
 
 	ret = i2c_smbus_read_byte(data->client1); /* read LSB, address 0x38 */
 	if (ret < 0)
-		goto out;
+		return ret;
+
 	lsb = ret;
 
 	/* shutdown again */
 	ret = i2c_smbus_write_byte(data->client1, data->config);
 	if (ret < 0)
-		goto out;
+		return ret;
 
 	ret = (msb << 8) | lsb;
 
-out:
-	mutex_unlock(&data->lock);
-	return ret;
+	return 0;
 }
 
 static const struct iio_chan_spec veml6070_channels[] = {
@@ -80,26 +145,37 @@ static const struct iio_chan_spec veml6070_channels[] = {
 		.modified = 1,
 		.channel2 = IIO_MOD_LIGHT_UV,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
+		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME),
 	},
 	{
 		.type = IIO_UVINDEX,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
+		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME),
 	}
 };
 
-static int veml6070_to_uv_index(unsigned val)
+static int veml6070_to_uv_index(struct veml6070_data *data, unsigned int val)
 {
 	/*
 	 * conversion of raw UV intensity values to UV index depends on
 	 * integration time (IT) and value of the resistor connected to
-	 * the RSET pin (default: 270 KOhm)
+	 * the RSET pin.
 	 */
-	unsigned uvi[11] = {
+	unsigned int uvi[11] = {
 		187, 373, 560, /* low */
 		746, 933, 1120, /* moderate */
 		1308, 1494, /* high */
 		1681, 1868, 2054}; /* very high */
-	int i;
+	int i, it_idx;
+
+	it_idx = FIELD_GET(VEML6070_COMMAND_IT, data->config);
+
+	if (!it_idx)
+		val = (val * 270  / data->rset) << 1;
+	else
+		val = (val * 270 / data->rset) >> (it_idx - 1);
 
 	for (i = 0; i < ARRAY_SIZE(uvi); i++)
 		if (val <= uvi[i])
@@ -122,10 +198,44 @@ static int veml6070_read_raw(struct iio_dev *indio_dev,
 		if (ret < 0)
 			return ret;
 		if (mask == IIO_CHAN_INFO_PROCESSED)
-			*val = veml6070_to_uv_index(ret);
+			*val = veml6070_to_uv_index(data, ret);
 		else
 			*val = ret;
 		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_INT_TIME:
+		return veml6070_get_it(data, val, val2);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int veml6070_read_avail(struct iio_dev *indio_dev,
+			       struct iio_chan_spec const *chan,
+			       const int **vals, int *type, int *length,
+			       long mask)
+{
+	struct veml6070_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_INT_TIME:
+		*vals = (int *)data->it;
+		*length = 2 * ARRAY_SIZE(data->it);
+		*type = IIO_VAL_INT_PLUS_MICRO;
+		return IIO_AVAIL_LIST;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int veml6070_write_raw(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *chan,
+			      int val, int val2, long mask)
+{
+	struct veml6070_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_INT_TIME:
+		return veml6070_set_it(data, val, val2);
 	default:
 		return -EINVAL;
 	}
@@ -133,8 +243,17 @@ static int veml6070_read_raw(struct iio_dev *indio_dev,
 
 static const struct iio_info veml6070_info = {
 	.read_raw = veml6070_read_raw,
+	.read_avail  = veml6070_read_avail,
+	.write_raw = veml6070_write_raw,
 };
 
+static void veml6070_i2c_unreg(void *p)
+{
+	struct veml6070_data *data = p;
+
+	i2c_unregister_device(data->client2);
+}
+
 static int veml6070_probe(struct i2c_client *client)
 {
 	struct veml6070_data *data;
@@ -156,50 +275,50 @@ static int veml6070_probe(struct i2c_client *client)
 	indio_dev->name = VEML6070_DRV_NAME;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
-	data->client2 = i2c_new_dummy_device(client->adapter, VEML6070_ADDR_DATA_LSB);
-	if (IS_ERR(data->client2)) {
-		dev_err(&client->dev, "i2c device for second chip address failed\n");
-		return PTR_ERR(data->client2);
-	}
-
-	data->config = VEML6070_IT_10 | VEML6070_COMMAND_RSRVD |
-		VEML6070_COMMAND_SD;
-	ret = i2c_smbus_write_byte(data->client1, data->config);
+	ret = veml6070_calc_it(&client->dev, data);
 	if (ret < 0)
-		goto fail;
+		return ret;
 
-	ret = iio_device_register(indio_dev);
+	ret = devm_regulator_get_enable(&client->dev, "vdd");
 	if (ret < 0)
-		goto fail;
+		return ret;
 
-	return ret;
+	data->client2 = i2c_new_dummy_device(client->adapter, VEML6070_ADDR_DATA_LSB);
+	if (IS_ERR(data->client2))
+		return dev_err_probe(&client->dev, PTR_ERR(data->client2),
+				     "i2c device for second chip address failed\n");
 
-fail:
-	i2c_unregister_device(data->client2);
-	return ret;
-}
+	data->config = FIELD_PREP(VEML6070_COMMAND_IT, VEML6070_IT_10) |
+		VEML6070_COMMAND_RSRVD | VEML6070_COMMAND_SD;
+	ret = i2c_smbus_write_byte(data->client1, data->config);
+	if (ret < 0)
+		return ret;
 
-static void veml6070_remove(struct i2c_client *client)
-{
-	struct iio_dev *indio_dev = i2c_get_clientdata(client);
-	struct veml6070_data *data = iio_priv(indio_dev);
+	ret = devm_add_action_or_reset(&client->dev, veml6070_i2c_unreg, data);
+	if (ret < 0)
+		return ret;
 
-	iio_device_unregister(indio_dev);
-	i2c_unregister_device(data->client2);
+	return devm_iio_device_register(&client->dev, indio_dev);
 }
 
 static const struct i2c_device_id veml6070_id[] = {
-	{ "veml6070", 0 },
+	{ "veml6070" },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, veml6070_id);
 
+static const struct of_device_id veml6070_of_match[] = {
+	{ .compatible = "vishay,veml6070" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, veml6070_of_match);
+
 static struct i2c_driver veml6070_driver = {
 	.driver = {
 		.name   = VEML6070_DRV_NAME,
+		.of_match_table = veml6070_of_match,
 	},
 	.probe = veml6070_probe,
-	.remove  = veml6070_remove,
 	.id_table = veml6070_id,
 };