LTR301 ALS support

Added support for Liteon 301 Ambient light sensor. Since LTR-301 and LTR-501 are register compatible(and even have same part id), LTR-501 driver has been extended to support both devices. LTR-501 is similar to LTR-301 in ALS sensing, But the only difference is, LTR-501 also supports proximity sensing.

LTR-501 - ALS + Proximity combo
LTR-301 - ALS sensor.

Signed-off-by Kuppuswamy Sathyanarayanan <[email protected]>

---
 drivers/iio/light/Kconfig  |  2 +-
 drivers/iio/light/ltr501.c | 99 +++++++++++++++++++++++++++++++++-------------
 2 files changed, 72 insertions(+), 29 deletions(-)

drivers/iio/light/Kconfig +1 -1

index a224afd..215e4a3 100644
@@ -159,7 +159,7 @@ config LTR501
 	select IIO_TRIGGERED_BUFFER
 	help
 	 If you say yes here you get support for the Lite-On LTR-501ALS-01
-	 ambient light and proximity sensor.
+	 ambient light and proximity sensor or LTR-301 ambient light sensor.
 
 	 This driver can also be built as a module.  If so, the module
          will be called ltr501.

drivers/iio/light/ltr501.c +71 -28

index 5939cda..4945405 100644
@@ -50,6 +50,7 @@
 enum {
 	ltr501 = 0,
 	ltr559,
+	ltr301,
 };
 
 struct ltr501_gain {

@@ -96,6 +97,8 @@ struct ltr501_chip_info {
 	u8 als_mode_active;
 	u8 als_gain_mask;
 	u8 als_gain_shift;
+	struct iio_chan_spec const *channels;
+	const struct iio_info *info;
 };
 
 struct ltr501_data {

@@ -105,29 +108,6 @@ struct ltr501_data {
 	u8 als_contr, ps_contr;
 };
 
-static struct ltr501_chip_info ltr501_chip_info_tbl[] = {
-	[ltr501] = {
-		.chip_id = 0x08,
-		.als_gain = ltr501_als_gain_tbl,
-		.als_gain_tbl_size = ARRAY_SIZE(ltr501_als_gain_tbl),
-		.ps_gain = ltr501_ps_gain_tbl,
-		.ps_gain_tbl_size = ARRAY_SIZE(ltr501_ps_gain_tbl),
-		.als_mode_active = BIT(0) | BIT(1),
-		.als_gain_mask = BIT(3),
-		.als_gain_shift = 3,
-	},
-	[ltr559] = {
-		.chip_id = 0x09,
-		.als_gain = ltr559_als_gain_tbl,
-		.als_gain_tbl_size = ARRAY_SIZE(ltr559_als_gain_tbl),
-		.ps_gain = ltr559_ps_gain_tbl,
-		.ps_gain_tbl_size = ARRAY_SIZE(ltr559_ps_gain_tbl),
-		.als_mode_active = BIT(1),
-		.als_gain_mask = BIT(2) | BIT(3) | BIT(4),
-		.als_gain_shift = 2,
-	},
-};
-
 static int ltr501_drdy(struct ltr501_data *data, u8 drdy_mask)
 {
 	int tries = 100;

@@ -202,6 +182,13 @@ static const struct iio_chan_spec ltr501_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(3),
 };
 
+static const struct iio_chan_spec ltr301_channels[] = {
+	LTR501_INTENSITY_CHANNEL(0, LTR501_ALS_DATA0, IIO_MOD_LIGHT_BOTH, 0),
+	LTR501_INTENSITY_CHANNEL(1, LTR501_ALS_DATA1, IIO_MOD_LIGHT_IR,
+				 BIT(IIO_CHAN_INFO_SCALE)),
+	IIO_CHAN_SOFT_TIMESTAMP(2),
+};
+
 static int ltr501_read_raw(struct iio_dev *indio_dev,
 			   struct iio_chan_spec const *chan,
 			   int *val, int *val2, long mask)

@@ -367,10 +354,19 @@ static struct attribute *ltr501_attributes[] = {
 	NULL
 };
 
+static struct attribute *ltr301_attributes[] = {
+	&iio_dev_attr_in_intensity_scale_available.dev_attr.attr,
+	NULL
+};
+
 static const struct attribute_group ltr501_attribute_group = {
 	.attrs = ltr501_attributes,
 };
 
+static const struct attribute_group ltr301_attribute_group = {
+	.attrs = ltr301_attributes,
+};
+
 static const struct iio_info ltr501_info = {
 	.read_raw = ltr501_read_raw,
 	.write_raw = ltr501_write_raw,

@@ -378,6 +374,50 @@ static const struct iio_info ltr501_info = {
 	.driver_module = THIS_MODULE,
 };
 
+static const struct iio_info ltr301_info = {
+	.read_raw = ltr501_read_raw,
+	.write_raw = ltr501_write_raw,
+	.attrs = &ltr301_attribute_group,
+	.driver_module = THIS_MODULE,
+};
+
+static struct ltr501_chip_info ltr501_chip_info_tbl[] = {
+	[ltr501] = {
+		.chip_id = 0x08,
+		.als_gain = ltr501_als_gain_tbl,
+		.als_gain_tbl_size = ARRAY_SIZE(ltr501_als_gain_tbl),
+		.ps_gain = ltr501_ps_gain_tbl,
+		.ps_gain_tbl_size = ARRAY_SIZE(ltr501_ps_gain_tbl),
+		.als_mode_active = BIT(0) | BIT(1),
+		.als_gain_mask = BIT(3),
+		.als_gain_shift = 3,
+		.info = &ltr501_info,
+		.channels = ltr501_channels,
+	},
+	[ltr559] = {
+		.chip_id = 0x09,
+		.als_gain = ltr559_als_gain_tbl,
+		.als_gain_tbl_size = ARRAY_SIZE(ltr559_als_gain_tbl),
+		.ps_gain = ltr559_ps_gain_tbl,
+		.ps_gain_tbl_size = ARRAY_SIZE(ltr559_ps_gain_tbl),
+		.als_mode_active = BIT(1),
+		.als_gain_mask = BIT(2) | BIT(3) | BIT(4),
+		.als_gain_shift = 2,
+		.info = &ltr501_info,
+		.channels = ltr501_channels,
+	},
+	[ltr301] = {
+		.chip_id = 0x08,
+		.als_gain = ltr501_als_gain_tbl,
+		.als_gain_tbl_size = ARRAY_SIZE(ltr501_als_gain_tbl),
+		.als_mode_active = BIT(0) | BIT(1),
+		.als_gain_mask = BIT(3),
+		.als_gain_shift = 3,
+		.info = &ltr301_info,
+		.channels = ltr301_channels,
+	},
+};
+
 static int ltr501_write_contr(struct i2c_client *client, u8 als_val, u8 ps_val)
 {
 	int ret = i2c_smbus_write_byte_data(client, LTR501_ALS_CONTR, als_val);

@@ -463,7 +503,7 @@ static int ltr501_probe(struct i2c_client *client,
 	struct ltr501_data *data;
 	struct iio_dev *indio_dev;
 	const char *name = NULL;
-	int chip_id = 0;
+	int chip_id;
 	int ret;
 
 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));

@@ -476,10 +516,12 @@ static int ltr501_probe(struct i2c_client *client,
 	mutex_init(&data->lock_als);
 	mutex_init(&data->lock_ps);
 
+	/* TODO: Add condition for ACPI */
 	if (id) {
-		name = id->name;
+		name = id->name ? id->name : LTR501_DRV_NAME;
 		chip_id = id->driver_data;
-	}
+	} else
+		return -ENODEV;
 
 	data->chip_info = &ltr501_chip_info_tbl[chip_id];
 

@@ -490,8 +532,8 @@ static int ltr501_probe(struct i2c_client *client,
 		return -ENODEV;
 
 	indio_dev->dev.parent = &client->dev;
-	indio_dev->info = &ltr501_info;
-	indio_dev->channels = ltr501_channels;
+	indio_dev->info = data->chip_info->info;
+	indio_dev->channels = data->chip_info->channels;
 	indio_dev->num_channels = ARRAY_SIZE(ltr501_channels);
 	indio_dev->name = name;
 	indio_dev->modes = INDIO_DIRECT_MODE;

@@ -557,6 +599,7 @@ static SIMPLE_DEV_PM_OPS(ltr501_pm_ops, ltr501_suspend, ltr501_resume);
 static const struct i2c_device_id ltr501_id[] = {
 	{ "ltr501", ltr501},
 	{ "ltr559", ltr559},
+	{ "ltr301", ltr301 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, ltr501_id);

Quoted 10 lines · Kuppuswamy Sathyanarayanan

Added support for Liteon 301 Ambient light sensor. Since LTR-301 and LTR-501 are register compatible(and even have same part id), LTR-501 driver has been extended to support both devices. LTR-501 is similar to LTR-301 in ALS sensing, But the only difference is, LTR-501 also supports proximity sensing.

LTR-501 - ALS + Proximity combo
LTR-301 - ALS sensor.

Signed-off-by Kuppuswamy Sathyanarayanan <[email protected]>

Looks good to me. Will either pick this up with Daniel's final series (trivial bits outstanding there) or separately if he doesn't pick it up. After his has gone in obviously!

Should I miss it by accident (it's been known to happen, particularly if a large delay happens for some reason :( then feel free to poke me!

Jonathan