[PATCH v3 0/2] shtc1: add support for device tree bindings

[PATCH v3 0/2] shtc1: add support for device tree bindings

[Chris Ruehl]

Add support for DTS bindings to the shtc driver
The patches add the compatible table and of_property_read_bool to the
shtc1.c. Newly created Yaml document has been released to the
Documentation/devicetree/hwmon/sensirion,shtc1.yaml

Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
---
 Version 3
	Fix errors report with checkpatch.pl
	Correct logic, add (!) when check for sensirion,low_precision
 Version 2
	remove the #ifdef CONFIG_OF
	ignore platform data if dev->of_node is valid
	use boolean only therefor use sensirion,low_precise to fit the logic
	add missing driver.of_match_table entry
 Version 1
	initial version

[PATCH v3 1/2] hwmon: shtc1: add support for device tree bindings

[Chris Ruehl]

Add support for DTS bindings for the sensirion shtc1,shtw1 and shtc3.

Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
---
 drivers/hwmon/shtc1.c | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/drivers/hwmon/shtc1.c b/drivers/hwmon/shtc1.c
index a0078ccede03..827d421b2b8f 100644
--- a/drivers/hwmon/shtc1.c
+++ b/drivers/hwmon/shtc1.c
@@ -14,6 +14,7 @@
 #include <linux/err.h>
 #include <linux/delay.h>
 #include <linux/platform_data/shtc1.h>
+#include <linux/of.h>
 
 /* commands (high precision mode) */
 static const unsigned char shtc1_cmd_measure_blocking_hpm[]    = { 0x7C, 0xA2 };
@@ -196,6 +197,7 @@ static int shtc1_probe(struct i2c_client *client,
 	enum shtcx_chips chip = id->driver_data;
 	struct i2c_adapter *adap = client->adapter;
 	struct device *dev = &client->dev;
+	struct device_node *np = dev->of_node;
 
 	if (!i2c_check_functionality(adap, I2C_FUNC_I2C)) {
 		dev_err(dev, "plain i2c transactions not supported\n");
@@ -233,8 +235,14 @@ static int shtc1_probe(struct i2c_client *client,
 	data->client = client;
 	data->chip = chip;
 
-	if (client->dev.platform_data)
-		data->setup = *(struct shtc1_platform_data *)dev->platform_data;
+	if (np) {
+		data->setup.blocking_io = of_property_read_bool(np, "sensirion,blocking_io");
+		data->setup.high_precision = !of_property_read_bool(np, "sensicon,low_precision");
+	} else {
+		if (client->dev.platform_data)
+			data->setup = *(struct shtc1_platform_data *)dev->platform_data;
+	}
+
 	shtc1_select_command(data);
 	mutex_init(&data->update_lock);
 
@@ -257,8 +265,19 @@ static const struct i2c_device_id shtc1_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, shtc1_id);
 
+static const struct of_device_id shtc1_of_match[] = {
+	{ .compatible = "sensirion,shtc1" },
+	{ .compatible = "sensirion,shtw1" },
+	{ .compatible = "sensirion,shtc3" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, shtc1_of_match);
+
 static struct i2c_driver shtc1_i2c_driver = {
-	.driver.name  = "shtc1",
+	.driver = {
+		.name = "shtc1",
+		.of_match_table = shtc1_of_match,
+	},
 	.probe        = shtc1_probe,
 	.id_table     = shtc1_id,
 };
-- 
2.20.1

[PATCH v3 2/2] devicetree: hwmon: shtc1: Add sensirion,shtc1.yaml

[Chris Ruehl]

Add documentation for the newly added DTS support in the shtc1 driver.
To align with the drivers logic to have high precision by default
a boolean sensirion,low_precision is used to switch to low precision.

Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
---
 .../bindings/hwmon/sensirion,shtc1.yaml       | 53 +++++++++++++++++++
 1 file changed, 53 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwmon/sensirion,shtc1.yaml

diff --git a/Documentation/devicetree/bindings/hwmon/sensirion,shtc1.yaml b/Documentation/devicetree/bindings/hwmon/sensirion,shtc1.yaml
new file mode 100644
index 000000000000..bcccdcadd86b
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/sensirion,shtc1.yaml
@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwmon/sensirion,shtc1.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Sensirion SHTC1 Humidity and Temperature Sensor IC
+
+maintainers:
+  - jdelvare@suse.com
+
+description: |
+  The SHTC1, SHTW1 and SHTC3 are digital humidity and temperature sensor
+  designed especially for battery-driven high-volume consumer electronics
+  applications.
+  For further information refere to Documentation/hwmon/shtc1.rst
+
+  This binding document describes the binding for the hardware monitor
+  portion of the driver.
+
+properties:
+  compatible:
+    enum:
+      - sensirion,shtc1
+      - sensirion,shtw1
+      - sensirion,shtc3
+
+  reg: I2C address 0x70
+
+Optional properties:
+  sensirion,blocking_io: |
+    bool, if set the i2c bus hold until measure finished
+  sensirion,low_precision: |
+    bool, if set aquire data with low precision (not recommend)
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+Example:
+  &i2c1 {
+    status = "okay";
+    clock-frequency = <400000>;
+
+    shtc3@70 {
+      compatible = "sensirion,shtc3";
+      reg = <0x70>
+      sensirion,blocking_io;
+      status = "okay";
+    };
+  };
-- 
2.20.1

Re: [PATCH v3 0/2] shtc1: add support for device tree bindings

[Chris Ruehl]

On 7/7/2020 4:01 pm, Chris Ruehl wrote:
> Add support for DTS bindings to the shtc driver
> The patches add the compatible table and of_property_read_bool to the
> shtc1.c. Newly created Yaml document has been released to the
> Documentation/devicetree/hwmon/sensirion,shtc1.yaml
> 
> Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
> ---
>   Version 3
> 	Fix errors report with checkpatch.pl
> 	Correct logic, add (!) when check for sensirion,low_precision
>   Version 2
> 	remove the #ifdef CONFIG_OF
> 	ignore platform data if dev->of_node is valid
> 	use boolean only therefor use sensirion,low_precise to fit the logic
> 	add missing driver.of_match_table entry
>   Version 1
> 	initial version
> 

I didn't fix the WARNINGS coming up with checkpatch, they are initial commit 
errors when added to the kernel.
But I have a patch pending to fix the format issue , once this is accepted.

Re: [PATCH v3 1/2] hwmon: shtc1: add support for device tree bindings

[Guenter Roeck]

On Tue, Jul 07, 2020 at 04:01:02PM +0800, Chris Ruehl wrote:
> Add support for DTS bindings for the sensirion shtc1,shtw1 and shtc3.
> 
> Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>

For my reference:

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

Waiting for feedback/approval from DT maintainers.

Thanks,
Guenter

> ---
>  drivers/hwmon/shtc1.c | 25 ++++++++++++++++++++++---
>  1 file changed, 22 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/hwmon/shtc1.c b/drivers/hwmon/shtc1.c
> index a0078ccede03..827d421b2b8f 100644
> --- a/drivers/hwmon/shtc1.c
> +++ b/drivers/hwmon/shtc1.c
> @@ -14,6 +14,7 @@
>  #include <linux/err.h>
>  #include <linux/delay.h>
>  #include <linux/platform_data/shtc1.h>
> +#include <linux/of.h>
>  
>  /* commands (high precision mode) */
>  static const unsigned char shtc1_cmd_measure_blocking_hpm[]    = { 0x7C, 0xA2 };
> @@ -196,6 +197,7 @@ static int shtc1_probe(struct i2c_client *client,
>  	enum shtcx_chips chip = id->driver_data;
>  	struct i2c_adapter *adap = client->adapter;
>  	struct device *dev = &client->dev;
> +	struct device_node *np = dev->of_node;
>  
>  	if (!i2c_check_functionality(adap, I2C_FUNC_I2C)) {
>  		dev_err(dev, "plain i2c transactions not supported\n");
> @@ -233,8 +235,14 @@ static int shtc1_probe(struct i2c_client *client,
>  	data->client = client;
>  	data->chip = chip;
>  
> -	if (client->dev.platform_data)
> -		data->setup = *(struct shtc1_platform_data *)dev->platform_data;
> +	if (np) {
> +		data->setup.blocking_io = of_property_read_bool(np, "sensirion,blocking_io");
> +		data->setup.high_precision = !of_property_read_bool(np, "sensicon,low_precision");
> +	} else {
> +		if (client->dev.platform_data)
> +			data->setup = *(struct shtc1_platform_data *)dev->platform_data;
> +	}
> +
>  	shtc1_select_command(data);
>  	mutex_init(&data->update_lock);
>  
> @@ -257,8 +265,19 @@ static const struct i2c_device_id shtc1_id[] = {
>  };
>  MODULE_DEVICE_TABLE(i2c, shtc1_id);
>  
> +static const struct of_device_id shtc1_of_match[] = {
> +	{ .compatible = "sensirion,shtc1" },
> +	{ .compatible = "sensirion,shtw1" },
> +	{ .compatible = "sensirion,shtc3" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, shtc1_of_match);
> +
>  static struct i2c_driver shtc1_i2c_driver = {
> -	.driver.name  = "shtc1",
> +	.driver = {
> +		.name = "shtc1",
> +		.of_match_table = shtc1_of_match,
> +	},
>  	.probe        = shtc1_probe,
>  	.id_table     = shtc1_id,
>  };
> -- 
> 2.20.1
>