From dc3ebfcaa51ff9ffa417f23e47c4e1aa01bc501d Mon Sep 17 00:00:00 2001
From: Matt Ranostay <matt.ranostay@konsulko.com>
Date: Mon, 17 Aug 2020 03:50:52 +0300
Subject: [PATCH] iio: chemical: atlas-ezo-sensor: add humidity sensor support

Add support for atlas,hum-ezo / humidity sensor which with scaling
provides respective data in millipercent

Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/chemical/atlas-ezo-sensor.c | 37 ++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/chemical/atlas-ezo-sensor.c b/drivers/iio/chemical/atlas-ezo-sensor.c
index 60a0c752fbc5..b1bacfe3c3ce 100644
--- a/drivers/iio/chemical/atlas-ezo-sensor.c
+++ b/drivers/iio/chemical/atlas-ezo-sensor.c
@@ -17,10 +17,12 @@
 
 #define ATLAS_EZO_DRV_NAME		"atlas-ezo-sensor"
 #define ATLAS_INT_TIME_IN_MS		950
+#define ATLAS_INT_HUM_TIME_IN_MS	350
 
 enum {
 	ATLAS_CO2_EZO,
 	ATLAS_O2_EZO,
+	ATLAS_HUM_EZO,
 };
 
 struct atlas_ezo_device {
@@ -63,6 +65,21 @@ static const struct iio_chan_spec atlas_o2_ezo_channels[] = {
 	ATLAS_CONCENTRATION_CHANNEL(IIO_MOD_O2),
 };
 
+static const struct iio_chan_spec atlas_hum_ezo_channels[] = {
+	{
+		.type = IIO_HUMIDITYRELATIVE,
+		.info_mask_separate =
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = 0,
+		.scan_type =  {
+			.sign = 'u',
+			.realbits = 32,
+			.storagebits = 32,
+			.endianness = IIO_CPU,
+		},
+	},
+};
+
 static struct atlas_ezo_device atlas_ezo_devices[] = {
 	[ATLAS_CO2_EZO] = {
 		.channels = atlas_co2_ezo_channels,
@@ -73,7 +90,12 @@ static struct atlas_ezo_device atlas_ezo_devices[] = {
 		.channels = atlas_o2_ezo_channels,
 		.num_channels = 1,
 		.delay = ATLAS_INT_TIME_IN_MS,
-	}
+	},
+	[ATLAS_HUM_EZO] = {
+		.channels = atlas_hum_ezo_channels,
+		.num_channels = 1,
+		.delay = ATLAS_INT_HUM_TIME_IN_MS,
+	},
 };
 
 static void atlas_ezo_sanitize(char *buf)
@@ -131,6 +153,17 @@ static int atlas_ezo_read_raw(struct iio_dev *indio_dev,
 		return ret ? ret : IIO_VAL_INT;
 	}
 	case IIO_CHAN_INFO_SCALE:
+		switch (chan->type) {
+		case IIO_HUMIDITYRELATIVE:
+			*val = 10;
+			return IIO_VAL_INT;
+		case IIO_CONCENTRATION:
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		/* IIO_CONCENTRATION modifiers */
 		switch (chan->channel2) {
 		case IIO_MOD_CO2:
 			*val = 0;
@@ -153,6 +186,7 @@ static const struct iio_info atlas_info = {
 static const struct i2c_device_id atlas_ezo_id[] = {
 	{ "atlas-co2-ezo", ATLAS_CO2_EZO },
 	{ "atlas-o2-ezo", ATLAS_O2_EZO },
+	{ "atlas-hum-ezo", ATLAS_HUM_EZO },
 	{}
 };
 MODULE_DEVICE_TABLE(i2c, atlas_ezo_id);
@@ -160,6 +194,7 @@ MODULE_DEVICE_TABLE(i2c, atlas_ezo_id);
 static const struct of_device_id atlas_ezo_dt_ids[] = {
 	{ .compatible = "atlas,co2-ezo", .data = (void *)ATLAS_CO2_EZO, },
 	{ .compatible = "atlas,o2-ezo", .data = (void *)ATLAS_O2_EZO, },
+	{ .compatible = "atlas,hum-ezo", .data = (void *)ATLAS_HUM_EZO, },
 	{}
 };
 MODULE_DEVICE_TABLE(of, atlas_ezo_dt_ids);