Add support for the Sensirion SHTC3 humidity and temperature sensor to
the shtc1 module.
Signed-off-by: Dan Robertson <d...@dlrobertson.com>
---
Documentation/hwmon/shtc1.rst | 19 +++++++++----
drivers/hwmon/Kconfig | 4 +--
drivers/hwmon/shtc1.c | 50 ++++++++++++++++++++++++++---------
3 files changed, 53 insertions(+), 20 deletions(-)
diff --git a/Documentation/hwmon/shtc1.rst b/Documentation/hwmon/shtc1.rst
index aa116332ba26..9b0f1eee5bf2 100644
--- a/Documentation/hwmon/shtc1.rst
+++ b/Documentation/hwmon/shtc1.rst
@@ -19,7 +19,17 @@ Supported chips:
Addresses scanned: none
- Datasheet: Not publicly available
+ Datasheet: http://www.sensirion.com/file/datasheet_shtw1
+
+
+
+ * Sensirion SHTC3
+
+ Prefix: 'shtc3'
+
+ Addresses scanned: none
+
+ Datasheet: http://www.sensirion.com/file/datasheet_shtc3
@@ -30,10 +40,9 @@ Author:
Description
-----------
-This driver implements support for the Sensirion SHTC1 chip, a humidity and
-temperature sensor. Temperature is measured in degrees celsius, relative
-humidity is expressed as a percentage. Driver can be used as well for SHTW1
-chip, which has the same electrical interface.
+This driver implements support for the Sensirion SHTC1, SHTW1, and SHTC3
+chips, a humidity and temperature sensor. Temperature is measured in degrees
+celsius, relative humidity is expressed as a percentage.
The device communicates with the I2C protocol. All sensors are set to I2C
address 0x70. See Documentation/i2c/instantiating-devices for methods to
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 650dd71f9724..e8b9b172ed9d 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1382,8 +1382,8 @@ config SENSORS_SHTC1
tristate "Sensiron humidity and temperature sensors. SHTC1 and compat."
depends on I2C
help
- If you say yes here you get support for the Sensiron SHTC1 and SHTW1
- humidity and temperature sensors.
+ If you say yes here you get support for the Sensiron SHTC1, SHTW1,
+ and SHTC3 humidity and temperature sensors.
This driver can also be built as a module. If so, the module
will be called shtc1.
diff --git a/drivers/hwmon/shtc1.c b/drivers/hwmon/shtc1.c
index 83fe08185ac7..d361030b07ab 100644
--- a/drivers/hwmon/shtc1.c
+++ b/drivers/hwmon/shtc1.c
@@ -24,19 +24,32 @@ static const unsigned char shtc1_cmd_measure_blocking_lpm[]
= { 0x64, 0x58 };
static const unsigned char shtc1_cmd_measure_nonblocking_lpm[] = { 0x60, 0x9c
};
/* command for reading the ID register */
-static const unsigned char shtc1_cmd_read_id_reg[] = { 0xef, 0xc8 };
+static const unsigned char shtc1_cmd_read_id_reg[] = { 0xef, 0xc8
};
-/* constants for reading the ID register */
-#define SHTC1_ID 0x07
-#define SHTC1_ID_REG_MASK 0x1f
+/* constants for reading the ID register
+ * SHTC1: 0x0007 with mask 0x003f
+ * SHTW1: 0x0007 with mask 0x001f
+ * SHTC3: 0x0807 with mask 0x081f
+ */
+#define SHTC3_ID 0x0807
+#define SHTC3_ID_MASK 0x083f
+#define SHTC1_ID 0x0007
+#define SHTC1_ID_MASK 0x001f
/* delays for non-blocking i2c commands, both in us */
#define SHTC1_NONBLOCKING_WAIT_TIME_HPM 14400
#define SHTC1_NONBLOCKING_WAIT_TIME_LPM 1000
+#define SHTC3_NONBLOCKING_WAIT_TIME_HPM 12100
+#define SHTC3_NONBLOCKING_WAIT_TIME_LPM 800
#define SHTC1_CMD_LENGTH 2
#define SHTC1_RESPONSE_LENGTH 6
+enum shtcx_chips {
+ shtc1,
+ shtc3,
+};
+
struct shtc1_data {
struct i2c_client *client;
struct mutex update_lock;
@@ -47,6 +60,7 @@ struct shtc1_data {
unsigned int nonblocking_wait_time; /* in us */
struct shtc1_platform_data setup;
+ enum shtcx_chips chip;
int temperature; /* 1000 * temperature in dgr C */
int humidity; /* 1000 * relative humidity in %RH */
@@ -157,13 +171,16 @@ static void shtc1_select_command(struct shtc1_data *data)
data->command = data->setup.blocking_io ?
shtc1_cmd_measure_blocking_hpm :
shtc1_cmd_measure_nonblocking_hpm;
- data->nonblocking_wait_time = SHTC1_NONBLOCKING_WAIT_TIME_HPM;
-
+ data->nonblocking_wait_time = (data->chip == shtc1) ?
+ SHTC1_NONBLOCKING_WAIT_TIME_HPM :
+ SHTC3_NONBLOCKING_WAIT_TIME_HPM;
} else {
data->command = data->setup.blocking_io ?
shtc1_cmd_measure_blocking_lpm :
shtc1_cmd_measure_nonblocking_lpm;
- data->nonblocking_wait_time = SHTC1_NONBLOCKING_WAIT_TIME_LPM;
+ data->nonblocking_wait_time = (data->chip == shtc1) ?
+ SHTC1_NONBLOCKING_WAIT_TIME_LPM :
+ SHTC3_NONBLOCKING_WAIT_TIME_LPM;
}
}
@@ -171,9 +188,11 @@ static int shtc1_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int ret;
- char id_reg[2];
+ u16 id_reg;
+ char id_reg_buf[2];
struct shtc1_data *data;
struct device *hwmon_dev;
+ enum shtcx_chips chip = id->driver_data;
struct i2c_adapter *adap = client->adapter;
struct device *dev = &client->dev;
@@ -187,12 +206,15 @@ static int shtc1_probe(struct i2c_client *client,
dev_err(dev, "could not send read_id_reg command: %d\n", ret);
return ret < 0 ? ret : -ENODEV;
}
- ret = i2c_master_recv(client, id_reg, sizeof(id_reg));
- if (ret != sizeof(id_reg)) {
+ ret = i2c_master_recv(client, id_reg_buf, sizeof(id_reg_buf));
+ if (ret != sizeof(id_reg_buf)) {
dev_err(dev, "could not read ID register: %d\n", ret);
return -ENODEV;
}
- if ((id_reg[1] & SHTC1_ID_REG_MASK) != SHTC1_ID) {
+
+ id_reg = be16_to_cpup((__be16 *)id_reg_buf);
+ if ((chip == shtc3 && (id_reg & SHTC3_ID_MASK) != SHTC3_ID) ||
+ ((id_reg & SHTC1_ID_MASK) != SHTC1_ID)) {
dev_err(dev, "ID register doesn't match\n");
return -ENODEV;
}
@@ -204,6 +226,7 @@ static int shtc1_probe(struct i2c_client *client,
data->setup.blocking_io = false;
data->setup.high_precision = true;
data->client = client;
+ data->chip = chip;
if (client->dev.platform_data)
data->setup = *(struct shtc1_platform_data *)dev->platform_data;
@@ -222,8 +245,9 @@ static int shtc1_probe(struct i2c_client *client,
/* device ID table */
static const struct i2c_device_id shtc1_id[] = {
- { "shtc1", 0 },
- { "shtw1", 0 },
+ { "shtc1", shtc1 },
+ { "shtw1", shtc1 },
+ { "shtc3", shtc3 },
{ }
};
MODULE_DEVICE_TABLE(i2c, shtc1_id);
--
2.23.0
