iio: chemical: atlas-sensor: add RTD-SM module support

Atlas Scientific RTD-SM OEM sensor reads temperature using
resistance temperature detector technology.
Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/chemical/atlas-sensor.c

@@ -53,6 +53,8 @@
 #define ATLAS_REG_DO_CALIB_STATUS_PRESSURE	BIT(0)
 #define ATLAS_REG_DO_CALIB_STATUS_DO		BIT(1)
 
+#define ATLAS_REG_RTD_DATA		0x0e
+
 #define ATLAS_REG_PH_TEMP_DATA		0x0e
 #define ATLAS_REG_PH_DATA		0x16
 
@@ -72,12 +74,14 @@
 #define ATLAS_EC_INT_TIME_IN_MS		650
 #define ATLAS_ORP_INT_TIME_IN_MS	450
 #define ATLAS_DO_INT_TIME_IN_MS		450
+#define ATLAS_RTD_INT_TIME_IN_MS	450
 
 enum {
 	ATLAS_PH_SM,
 	ATLAS_EC_SM,
 	ATLAS_ORP_SM,
 	ATLAS_DO_SM,
+	ATLAS_RTD_SM,
 };
 
 struct atlas_data {
@@ -206,6 +210,22 @@ static const struct iio_chan_spec atlas_do_channels[] = {
 	},
 };
 
+static const struct iio_chan_spec atlas_rtd_channels[] = {
+	{
+		.type = IIO_TEMP,
+		.address = ATLAS_REG_RTD_DATA,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+		.scan_index = 0,
+		.scan_type = {
+			.sign = 's',
+			.realbits = 32,
+			.storagebits = 32,
+			.endianness = IIO_BE,
+		},
+	},
+	IIO_CHAN_SOFT_TIMESTAMP(1),
+};
+
 static int atlas_check_ph_calibration(struct atlas_data *data)
 {
 	struct device *dev = &data->client->dev;
@@ -350,6 +370,12 @@ static struct atlas_device atlas_devices[] = {
 				.calibration = &atlas_check_do_calibration,
 				.delay = ATLAS_DO_INT_TIME_IN_MS,
 	},
+	[ATLAS_RTD_SM] = {
+				.channels = atlas_rtd_channels,
+				.num_channels = 2,
+				.data_reg = ATLAS_REG_RTD_DATA,
+				.delay = ATLAS_RTD_INT_TIME_IN_MS,
+	},
 };
 
 static int atlas_set_powermode(struct atlas_data *data, int on)
@@ -477,6 +503,7 @@ static int atlas_read_raw(struct iio_dev *indio_dev,
 	struct atlas_data *data = iio_priv(indio_dev);
 
 	switch (mask) {
+	case IIO_CHAN_INFO_PROCESSED:
 	case IIO_CHAN_INFO_RAW: {
 		int ret;
 		__be32 reg;
@@ -565,6 +592,7 @@ static const struct i2c_device_id atlas_id[] = {
 	{ "atlas-ec-sm", ATLAS_EC_SM},
 	{ "atlas-orp-sm", ATLAS_ORP_SM},
 	{ "atlas-do-sm", ATLAS_DO_SM},
+	{ "atlas-rtd-sm", ATLAS_RTD_SM},
 	{}
 };
 MODULE_DEVICE_TABLE(i2c, atlas_id);
@@ -574,6 +602,7 @@ static const struct of_device_id atlas_dt_ids[] = {
 	{ .compatible = "atlas,ec-sm", .data = (void *)ATLAS_EC_SM, },
 	{ .compatible = "atlas,orp-sm", .data = (void *)ATLAS_ORP_SM, },
 	{ .compatible = "atlas,do-sm", .data = (void *)ATLAS_DO_SM, },
+	{ .compatible = "atlas,rtd-sm", .data = (void *)ATLAS_RTD_SM, },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, atlas_dt_ids);