[PATCH v2 0/3] Add W83773G hwmon sensor driver and doc

[PATCH v2 0/3] Add W83773G hwmon sensor driver and doc

[Lei YU]

Nuvoton W83773G is a hardware monitoring chip, which integrates two remote
and one local temperature sensors.
---
v2:
 - The driver is re-written as v1's comment, so the author is changed to me.
 - Added the device to trivial-devices.txt

Lei YU (3):
  DT: i2c: W83773G is a trivial device
  drivers: hwmon: Add W83773G driver
  hwmon: (w83773g) Add documentation

 .../devicetree/bindings/trivial-devices.txt        |   1 +
 Documentation/hwmon/w83773g                        |  33 +++
 drivers/hwmon/Kconfig                              |  10 +
 drivers/hwmon/Makefile                             |   1 +
 drivers/hwmon/w83773g.c                            | 281 +++++++++++++++++++++
 5 files changed, 326 insertions(+)
 create mode 100644 Documentation/hwmon/w83773g
 create mode 100644 drivers/hwmon/w83773g.c

-- 
1.9.1

[PATCH v2 1/3] DT: i2c: W83773G is a trivial device

[Lei YU]

Signed-off-by: Lei YU <mine260309@gmail.com>
---
 Documentation/devicetree/bindings/trivial-devices.txt | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/trivial-devices.txt b/Documentation/devicetree/bindings/trivial-devices.txt
index af284fb..63ad2f1 100644
--- a/Documentation/devicetree/bindings/trivial-devices.txt
+++ b/Documentation/devicetree/bindings/trivial-devices.txt
@@ -188,3 +188,4 @@ ti,tmp103		Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Inter
 ti,tmp275		Digital Temperature Sensor
 winbond,w83793		Winbond/Nuvoton H/W Monitor
 winbond,wpct301		i2c trusted platform module (TPM)
+nuvoton,w83773g		Nuvoton Temperature Sensor
-- 
1.9.1

[PATCH v2 2/3] drivers: hwmon: Add W83773G driver

[Lei YU]

Nuvoton W83773G is a hardware monitor IC providing one local
temperature and two remote temperature sensors.

Signed-off-by: Lei YU <mine260309@gmail.com>
---
v2:
 - Rewrite the driver using regmap
 - Add offset and update_interval
---
 drivers/hwmon/Kconfig   |  10 ++
 drivers/hwmon/Makefile  |   1 +
 drivers/hwmon/w83773g.c | 281 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 292 insertions(+)
 create mode 100644 drivers/hwmon/w83773g.c

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index d654314..11c6248 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1710,6 +1710,16 @@ config SENSORS_VT8231
 	  This driver can also be built as a module.  If so, the module
 	  will be called vt8231.
 
+config SENSORS_W83773G
+	tristate "Nuvoton W83773G"
+	depends on I2C
+	help
+	  If you say yes here you get support for the Nuvoton W83773G hardware
+	  monitoring chip.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called w83773g.
+
 config SENSORS_W83781D
 	tristate "Winbond W83781D, W83782D, W83783S, Asus AS99127F"
 	depends on I2C
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index c84d978..0649ad8 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_SENSORS_ATK0110)	+= asus_atk0110.o
 # asb100, then w83781d go first, as they can override other drivers' addresses.
 obj-$(CONFIG_SENSORS_ASB100)	+= asb100.o
 obj-$(CONFIG_SENSORS_W83627HF)	+= w83627hf.o
+obj-$(CONFIG_SENSORS_W83773G)	+= w83773g.o
 obj-$(CONFIG_SENSORS_W83792D)	+= w83792d.o
 obj-$(CONFIG_SENSORS_W83793)	+= w83793.o
 obj-$(CONFIG_SENSORS_W83795)	+= w83795.o
diff --git a/drivers/hwmon/w83773g.c b/drivers/hwmon/w83773g.c
new file mode 100644
index 0000000..d352bac
--- /dev/null
+++ b/drivers/hwmon/w83773g.c
@@ -0,0 +1,281 @@
+/*
+ * Copyright (C) 2017 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Driver for the Nuvoton W83773G SMBus temperature sensor IC.
+ * Supported models: W83773G
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+
+/* Addresses to scan */
+static const unsigned short normal_i2c[] = { 0x4c, 0x4d, I2C_CLIENT_END };
+
+/* The W83773 registers */
+#define W83773_CONVERSION_RATE_REG_READ		0x04
+#define W83773_CONVERSION_RATE_REG_WRITE	0x0A
+#define W83773_MANUFACTURER_ID_REG		0xFE
+#define W83773_LOCAL_TEMP			0x00
+
+static const u8 W83773_STATUS[2] = { 0x02, 0x17 };
+
+static const u8 W83773_TEMP_LSB[2] = { 0x10, 0x25 };
+static const u8 W83773_TEMP_MSB[2] = { 0x01, 0x24 };
+
+static const u8 W83773_OFFSET_LSB[2] = { 0x12, 0x16 };
+static const u8 W83773_OFFSET_MSB[2] = { 0x11, 0x15 };
+
+
+/* this is the number of sensors in the device */
+static const struct i2c_device_id w83773_id[] = {
+	{ "w83773g" },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(i2c, w83773_id);
+
+static const struct of_device_id w83773_of_match[] = {
+	{
+		.compatible = "nuvoton,w83773g"
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, w83773_of_match);
+
+static inline int temp_of_local(s8 reg)
+{
+	return reg * 1000;
+}
+
+static inline int temp_of_remote(s8 hb, u8 lb)
+{
+	return (hb << 3 | lb >> 5) * 125;
+}
+
+static ssize_t show_local_temp(struct device *dev,
+			       struct device_attribute *attr,
+			       char *buf)
+{
+	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
+	struct regmap *regmap = dev_get_drvdata(dev);
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_read(regmap, sda->index, &regval);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%d\n", temp_of_local(regval));
+}
+
+static ssize_t show_remote_temp(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
+	struct regmap *regmap = dev_get_drvdata(dev);
+	unsigned int regval_high;
+	unsigned int regval_low;
+	int ret;
+
+	ret = regmap_read(regmap, W83773_TEMP_MSB[sda->index], &regval_high);
+	ret |= regmap_read(regmap, W83773_TEMP_LSB[sda->index], &regval_low);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%d\n", temp_of_remote(regval_high, regval_low));
+}
+
+static ssize_t show_status(struct device *dev,
+			   struct device_attribute *attr,
+			   char *buf)
+{
+	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
+	struct regmap *regmap = dev_get_drvdata(dev);
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_read(regmap, W83773_STATUS[sda->index], &regval);
+
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%d\n", (u8)regval & 0x04 >> 2);
+}
+
+static ssize_t show_offset(struct device *dev,
+			   struct device_attribute *attr,
+			   char *buf)
+{
+	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
+	struct regmap *regmap = dev_get_drvdata(dev);
+	unsigned int regval_high;
+	unsigned int regval_low;
+	int ret;
+
+	ret = regmap_read(regmap, W83773_OFFSET_MSB[sda->index], &regval_high);
+	ret |= regmap_read(regmap, W83773_OFFSET_LSB[sda->index], &regval_low);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%d\n", temp_of_remote(regval_high, regval_low));
+}
+
+static ssize_t set_offset(struct device *dev,
+			  struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
+	struct regmap *regmap = dev_get_drvdata(dev);
+	long val;
+	int ret;
+	int err;
+	u8 high_byte;
+	u8 low_byte;
+
+	err = kstrtol(buf, 10, &val);
+	if (err)
+		return err;
+
+	val = clamp_val(val, -127825, 127825);
+	/* offset value equals to (high_byte << 3 | low_byte >> 5) * 125 */
+	val /= 125;
+	high_byte = val >> 3;
+	low_byte = (val & 0x07) << 5;
+
+	ret = regmap_write(regmap, W83773_OFFSET_MSB[sda->index], high_byte);
+	ret |= regmap_write(regmap, W83773_OFFSET_LSB[sda->index], low_byte);
+
+	if (ret < 0)
+		return ret;
+	return count;
+}
+
+static ssize_t show_update_interval(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	struct regmap *regmap = dev_get_drvdata(dev);
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_read(regmap, W83773_CONVERSION_RATE_REG_READ, &regval);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%u\n", 16000 >> regval);
+}
+
+static ssize_t set_update_interval(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf, size_t count)
+{
+	struct regmap *regmap = dev_get_drvdata(dev);
+	unsigned long val;
+	int ret;
+	int err, rate;
+
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+
+	/*
+	 * For valid rates, interval can be calculated as
+	 *	interval = (1 << (8 - rate)) * 62.5;
+	 * Rounded rate is therefore
+	 *	rate = 8 - __fls(interval * 8 / (62.5 * 7));
+	 * Use clamp_val() to avoid overflows, and to ensure valid input
+	 * for __fls.
+	 */
+	val = clamp_val(val, 62, 16000) * 10;
+	rate = 8 - __fls((val * 8 / (625 * 7)));
+	ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE, rate);
+	if (ret < 0)
+		return ret;
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, 0444, show_local_temp, NULL,
+			  W83773_LOCAL_TEMP);
+static SENSOR_DEVICE_ATTR(temp2_input, 0444, show_remote_temp, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_fault, 0444, show_status, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_offset, 0644, show_offset, set_offset, 0);
+static SENSOR_DEVICE_ATTR(temp3_input, 0444, show_remote_temp, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp3_fault, 0444, show_status, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp3_offset, 0644, show_offset, set_offset, 1);
+static DEVICE_ATTR(update_interval, 0644, show_update_interval,
+		   set_update_interval);
+
+static struct attribute *w83773g_attrs[] = {
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	&sensor_dev_attr_temp2_input.dev_attr.attr,
+	&sensor_dev_attr_temp2_fault.dev_attr.attr,
+	&sensor_dev_attr_temp2_offset.dev_attr.attr,
+	&sensor_dev_attr_temp3_input.dev_attr.attr,
+	&sensor_dev_attr_temp3_fault.dev_attr.attr,
+	&sensor_dev_attr_temp3_offset.dev_attr.attr,
+	&dev_attr_update_interval.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(w83773g);
+
+static const struct regmap_config w83773g_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+};
+
+static int w83773_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+
+	struct device *dev = &client->dev;
+	struct device *hwmon_dev;
+	struct regmap *regmap;
+	int ret;
+
+	regmap = devm_regmap_init_i2c(client, &w83773g_regmap_config);
+	if (IS_ERR(regmap)) {
+		dev_err(dev, "failed to allocate register map\n");
+		return PTR_ERR(regmap);
+	}
+
+	/* Set the conversion rate to 2 Hz */
+	ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE, 0x05);
+	if (ret < 0) {
+		dev_err(&client->dev, "error writing config rate register\n");
+		return ret;
+	}
+
+	i2c_set_clientdata(client, regmap);
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+						      regmap, w83773g_groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static struct i2c_driver w83773_driver = {
+	.class = I2C_CLASS_HWMON,
+	.driver = {
+		.name	= "w83773g",
+		.of_match_table = of_match_ptr(w83773_of_match),
+	},
+	.probe = w83773_probe,
+	.id_table = w83773_id,
+	.address_list = normal_i2c,
+};
+
+module_i2c_driver(w83773_driver);
+
+MODULE_AUTHOR("Lei YU <mine260309@gmail.com>");
+MODULE_DESCRIPTION("W83773G temperature sensor driver");
+MODULE_LICENSE("GPL");
-- 
1.9.1

[PATCH v2 3/3] hwmon: (w83773g) Add documentation

[Lei YU]

Add documentation for the w83773g driver.

Signed-off-by: Lei YU <mine260309@gmail.com>
---
v2:
 - Add notes for offset and update_interval
---
 Documentation/hwmon/w83773g | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 Documentation/hwmon/w83773g

diff --git a/Documentation/hwmon/w83773g b/Documentation/hwmon/w83773g
new file mode 100644
index 0000000..4cc6c0b
--- /dev/null
+++ b/Documentation/hwmon/w83773g
@@ -0,0 +1,33 @@
+Kernel driver w83773g
+====================
+
+Supported chips:
+  * Nuvoton W83773G
+    Prefix: 'w83773g'
+    Addresses scanned: I2C 0x4c and 0x4d
+    Datasheet: https://www.nuvoton.com/resource-files/W83773G_SG_DatasheetV1_2.pdf
+
+Authors:
+	Lei YU <mine260309@gmail.com>
+
+Description
+-----------
+
+This driver implements support for Nuvoton W83773G temperature sensor
+chip. This chip implements one local and two remote sensors.
+The chip also features offsets for the two remote sensors which get added to
+the input readings. The chip does all the scaling by itself and the driver
+therefore reports true temperatures that don't need any user-space adjustments.
+Temperature is measured in degrees Celsius.
+The chip is wired over I2C/SMBus and specified over a temperature
+range of -40 to +125 degrees Celsius (for local sensor) and -40 to +127
+degrees Celsius (for remote sensors).
+Resolution for both the local and remote channels is 0.125 degree C.
+
+The chip supports only temperature measurement. The driver exports
+the temperature values via the following sysfs files:
+
+temp[1-3]_input
+temp[2-3]_fault
+temp[2-3]_offset
+update_interval
-- 
1.9.1

Re: [PATCH v2 2/3] drivers: hwmon: Add W83773G driver

[Guenter Roeck]

On 11/07/2017 12:27 AM, Lei YU wrote:
> Nuvoton W83773G is a hardware monitor IC providing one local
> temperature and two remote temperature sensors.
> 
> Signed-off-by: Lei YU <mine260309@gmail.com>
> ---
> v2:
>   - Rewrite the driver using regmap
>   - Add offset and update_interval
> ---
>   drivers/hwmon/Kconfig   |  10 ++
>   drivers/hwmon/Makefile  |   1 +
>   drivers/hwmon/w83773g.c | 281 ++++++++++++++++++++++++++++++++++++++++++++++++
>   3 files changed, 292 insertions(+)
>   create mode 100644 drivers/hwmon/w83773g.c
> 
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index d654314..11c6248 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -1710,6 +1710,16 @@ config SENSORS_VT8231
>   	  This driver can also be built as a module.  If so, the module
>   	  will be called vt8231.
>   
> +config SENSORS_W83773G
> +	tristate "Nuvoton W83773G"
> +	depends on I2C
> +	help
> +	  If you say yes here you get support for the Nuvoton W83773G hardware
> +	  monitoring chip.
> +
> +	  This driver can also be built as a module.  If so, the module
> +	  will be called w83773g.
> +
>   config SENSORS_W83781D
>   	tristate "Winbond W83781D, W83782D, W83783S, Asus AS99127F"
>   	depends on I2C
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index c84d978..0649ad8 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -13,6 +13,7 @@ obj-$(CONFIG_SENSORS_ATK0110)	+= asus_atk0110.o
>   # asb100, then w83781d go first, as they can override other drivers' addresses.
>   obj-$(CONFIG_SENSORS_ASB100)	+= asb100.o
>   obj-$(CONFIG_SENSORS_W83627HF)	+= w83627hf.o
> +obj-$(CONFIG_SENSORS_W83773G)	+= w83773g.o
>   obj-$(CONFIG_SENSORS_W83792D)	+= w83792d.o
>   obj-$(CONFIG_SENSORS_W83793)	+= w83793.o
>   obj-$(CONFIG_SENSORS_W83795)	+= w83795.o
> diff --git a/drivers/hwmon/w83773g.c b/drivers/hwmon/w83773g.c
> new file mode 100644
> index 0000000..d352bac
> --- /dev/null
> +++ b/drivers/hwmon/w83773g.c
> @@ -0,0 +1,281 @@
> +/*
> + * Copyright (C) 2017 IBM Corp.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * Driver for the Nuvoton W83773G SMBus temperature sensor IC.
> + * Supported models: W83773G
> + */
> +
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/i2c.h>
> +#include <linux/hwmon.h>
> +#include <linux/hwmon-sysfs.h>
> +#include <linux/err.h>
> +#include <linux/of_device.h>
> +#include <linux/regmap.h>
> +
> +/* Addresses to scan */
> +static const unsigned short normal_i2c[] = { 0x4c, 0x4d, I2C_CLIENT_END };
> +
> +/* The W83773 registers */
> +#define W83773_CONVERSION_RATE_REG_READ		0x04
> +#define W83773_CONVERSION_RATE_REG_WRITE	0x0A
> +#define W83773_MANUFACTURER_ID_REG		0xFE
> +#define W83773_LOCAL_TEMP			0x00
> +
> +static const u8 W83773_STATUS[2] = { 0x02, 0x17 };
> +
> +static const u8 W83773_TEMP_LSB[2] = { 0x10, 0x25 };
> +static const u8 W83773_TEMP_MSB[2] = { 0x01, 0x24 };
> +
> +static const u8 W83773_OFFSET_LSB[2] = { 0x12, 0x16 };
> +static const u8 W83773_OFFSET_MSB[2] = { 0x11, 0x15 };
> +
> +
> +/* this is the number of sensors in the device */
> +static const struct i2c_device_id w83773_id[] = {
> +	{ "w83773g" },
> +	{ }
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, w83773_id);
> +
> +static const struct of_device_id w83773_of_match[] = {
> +	{
> +		.compatible = "nuvoton,w83773g"
> +	},
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, w83773_of_match);
> +
> +static inline int temp_of_local(s8 reg)
> +{
> +	return reg * 1000;
> +}
> +
> +static inline int temp_of_remote(s8 hb, u8 lb)
> +{
> +	return (hb << 3 | lb >> 5) * 125;
> +}
> +
> +static ssize_t show_local_temp(struct device *dev,
> +			       struct device_attribute *attr,
> +			       char *buf)
> +{
> +	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
> +	struct regmap *regmap = dev_get_drvdata(dev);
> +	unsigned int regval;
> +	int ret;
> +
> +	ret = regmap_read(regmap, sda->index, &regval);
> +	if (ret < 0)
> +		return ret;
> +
> +	return sprintf(buf, "%d\n", temp_of_local(regval));
> +}
> +
> +static ssize_t show_remote_temp(struct device *dev,
> +				struct device_attribute *attr,
> +				char *buf)
> +{
> +	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
> +	struct regmap *regmap = dev_get_drvdata(dev);
> +	unsigned int regval_high;
> +	unsigned int regval_low;
> +	int ret;
> +
> +	ret = regmap_read(regmap, W83773_TEMP_MSB[sda->index], &regval_high);
> +	ret |= regmap_read(regmap, W83773_TEMP_LSB[sda->index], &regval_low);
> +	if (ret < 0)
> +		return ret;
> +
> +	return sprintf(buf, "%d\n", temp_of_remote(regval_high, regval_low));
> +}
> +
> +static ssize_t show_status(struct device *dev,
> +			   struct device_attribute *attr,
> +			   char *buf)
> +{
> +	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
> +	struct regmap *regmap = dev_get_drvdata(dev);
> +	unsigned int regval;
> +	int ret;
> +
> +	ret = regmap_read(regmap, W83773_STATUS[sda->index], &regval);
> +
> +	if (ret < 0)
> +		return ret;
> +
> +	return sprintf(buf, "%d\n", (u8)regval & 0x04 >> 2);
> +}
> +
> +static ssize_t show_offset(struct device *dev,
> +			   struct device_attribute *attr,
> +			   char *buf)
> +{
> +	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
> +	struct regmap *regmap = dev_get_drvdata(dev);
> +	unsigned int regval_high;
> +	unsigned int regval_low;
> +	int ret;
> +
> +	ret = regmap_read(regmap, W83773_OFFSET_MSB[sda->index], &regval_high);
> +	ret |= regmap_read(regmap, W83773_OFFSET_LSB[sda->index], &regval_low);
> +	if (ret < 0)
> +		return ret;
> +
> +	return sprintf(buf, "%d\n", temp_of_remote(regval_high, regval_low));
> +}
> +
> +static ssize_t set_offset(struct device *dev,
> +			  struct device_attribute *attr,
> +			  const char *buf, size_t count)
> +{
> +	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
> +	struct regmap *regmap = dev_get_drvdata(dev);
> +	long val;
> +	int ret;
> +	int err;
> +	u8 high_byte;
> +	u8 low_byte;
> +
> +	err = kstrtol(buf, 10, &val);
> +	if (err)
> +		return err;
> +
> +	val = clamp_val(val, -127825, 127825);
> +	/* offset value equals to (high_byte << 3 | low_byte >> 5) * 125 */
> +	val /= 125;
> +	high_byte = val >> 3;
> +	low_byte = (val & 0x07) << 5;
> +
> +	ret = regmap_write(regmap, W83773_OFFSET_MSB[sda->index], high_byte);
> +	ret |= regmap_write(regmap, W83773_OFFSET_LSB[sda->index], low_byte);

Please don't do that. The errors, if any, might be different, messing up
the error return.

> +
> +	if (ret < 0)
> +		return ret;
> +	return count;
> +}
> +
> +static ssize_t show_update_interval(struct device *dev,
> +				    struct device_attribute *attr,
> +				    char *buf)
> +{
> +	struct regmap *regmap = dev_get_drvdata(dev);
> +	unsigned int regval;
> +	int ret;
> +
> +	ret = regmap_read(regmap, W83773_CONVERSION_RATE_REG_READ, &regval);
> +	if (ret < 0)
> +		return ret;
> +
> +	return sprintf(buf, "%u\n", 16000 >> regval);
> +}
> +
> +static ssize_t set_update_interval(struct device *dev,
> +				   struct device_attribute *attr,
> +				   const char *buf, size_t count)
> +{
> +	struct regmap *regmap = dev_get_drvdata(dev);
> +	unsigned long val;
> +	int ret;
> +	int err, rate;
> +
> +	err = kstrtoul(buf, 10, &val);
> +	if (err)
> +		return err;
> +
> +	/*
> +	 * For valid rates, interval can be calculated as
> +	 *	interval = (1 << (8 - rate)) * 62.5;
> +	 * Rounded rate is therefore
> +	 *	rate = 8 - __fls(interval * 8 / (62.5 * 7));
> +	 * Use clamp_val() to avoid overflows, and to ensure valid input
> +	 * for __fls.
> +	 */
> +	val = clamp_val(val, 62, 16000) * 10;
> +	rate = 8 - __fls((val * 8 / (625 * 7)));
> +	ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE, rate);
> +	if (ret < 0)
> +		return ret;
> +	return count;
> +}
> +
> +static SENSOR_DEVICE_ATTR(temp1_input, 0444, show_local_temp, NULL,
> +			  W83773_LOCAL_TEMP);
> +static SENSOR_DEVICE_ATTR(temp2_input, 0444, show_remote_temp, NULL, 0);
> +static SENSOR_DEVICE_ATTR(temp2_fault, 0444, show_status, NULL, 0);
> +static SENSOR_DEVICE_ATTR(temp2_offset, 0644, show_offset, set_offset, 0);
> +static SENSOR_DEVICE_ATTR(temp3_input, 0444, show_remote_temp, NULL, 1);
> +static SENSOR_DEVICE_ATTR(temp3_fault, 0444, show_status, NULL, 1);
> +static SENSOR_DEVICE_ATTR(temp3_offset, 0644, show_offset, set_offset, 1);
> +static DEVICE_ATTR(update_interval, 0644, show_update_interval,
> +		   set_update_interval);
> +
> +static struct attribute *w83773g_attrs[] = {
> +	&sensor_dev_attr_temp1_input.dev_attr.attr,
> +	&sensor_dev_attr_temp2_input.dev_attr.attr,
> +	&sensor_dev_attr_temp2_fault.dev_attr.attr,
> +	&sensor_dev_attr_temp2_offset.dev_attr.attr,
> +	&sensor_dev_attr_temp3_input.dev_attr.attr,
> +	&sensor_dev_attr_temp3_fault.dev_attr.attr,
> +	&sensor_dev_attr_temp3_offset.dev_attr.attr,
> +	&dev_attr_update_interval.attr,
> +	NULL
> +};
> +ATTRIBUTE_GROUPS(w83773g);
> +
> +static const struct regmap_config w83773g_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +};
> +
> +static int w83773_probe(struct i2c_client *client,
> +			const struct i2c_device_id *id)
> +{
> +
> +	struct device *dev = &client->dev;
> +	struct device *hwmon_dev;
> +	struct regmap *regmap;
> +	int ret;
> +
> +	regmap = devm_regmap_init_i2c(client, &w83773g_regmap_config);
> +	if (IS_ERR(regmap)) {
> +		dev_err(dev, "failed to allocate register map\n");
> +		return PTR_ERR(regmap);
> +	}
> +
> +	/* Set the conversion rate to 2 Hz */
> +	ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE, 0x05);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "error writing config rate register\n");
> +		return ret;
> +	}
> +
> +	i2c_set_clientdata(client, regmap);
> +	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
> +						      regmap, w83773g_groups);

You lost me here. Why did you stop using the new API ?

Guenter

> +	return PTR_ERR_OR_ZERO(hwmon_dev);
> +}
> +
> +static struct i2c_driver w83773_driver = {
> +	.class = I2C_CLASS_HWMON,
> +	.driver = {
> +		.name	= "w83773g",
> +		.of_match_table = of_match_ptr(w83773_of_match),
> +	},
> +	.probe = w83773_probe,
> +	.id_table = w83773_id,
> +	.address_list = normal_i2c,
> +};
> +
> +module_i2c_driver(w83773_driver);
> +
> +MODULE_AUTHOR("Lei YU <mine260309@gmail.com>");
> +MODULE_DESCRIPTION("W83773G temperature sensor driver");
> +MODULE_LICENSE("GPL");
> 

Re: [PATCH v2 2/3] drivers: hwmon: Add W83773G driver

[Lei YU]

On Tue, Nov 7, 2017 at 10:33 PM, Guenter Roeck <linux@roeck-us.net> wrote:
> On 11/07/2017 12:27 AM, Lei YU wrote:
>>
>> Nuvoton W83773G is a hardware monitor IC providing one local
>> temperature and two remote temperature sensors.
>>
>> Signed-off-by: Lei YU <mine260309@gmail.com>
>> ---
>> v2:
>>   - Rewrite the driver using regmap
>>   - Add offset and update_interval
>> ---
>>   drivers/hwmon/Kconfig   |  10 ++
>>   drivers/hwmon/Makefile  |   1 +
>>   drivers/hwmon/w83773g.c | 281
>> ++++++++++++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 292 insertions(+)
>>   create mode 100644 drivers/hwmon/w83773g.c
>>
>> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
>> index d654314..11c6248 100644
>> --- a/drivers/hwmon/Kconfig
>> +++ b/drivers/hwmon/Kconfig
>> @@ -1710,6 +1710,16 @@ config SENSORS_VT8231
>>           This driver can also be built as a module.  If so, the module
>>           will be called vt8231.
>>   +config SENSORS_W83773G
>> +       tristate "Nuvoton W83773G"
>> +       depends on I2C
>> +       help
>> +         If you say yes here you get support for the Nuvoton W83773G
>> hardware
>> +         monitoring chip.
>> +
>> +         This driver can also be built as a module.  If so, the module
>> +         will be called w83773g.
>> +
>>   config SENSORS_W83781D
>>         tristate "Winbond W83781D, W83782D, W83783S, Asus AS99127F"
>>         depends on I2C
>> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
>> index c84d978..0649ad8 100644
>> --- a/drivers/hwmon/Makefile
>> +++ b/drivers/hwmon/Makefile
>> @@ -13,6 +13,7 @@ obj-$(CONFIG_SENSORS_ATK0110) += asus_atk0110.o
>>   # asb100, then w83781d go first, as they can override other drivers'
>> addresses.
>>   obj-$(CONFIG_SENSORS_ASB100)  += asb100.o
>>   obj-$(CONFIG_SENSORS_W83627HF)        += w83627hf.o
>> +obj-$(CONFIG_SENSORS_W83773G)  += w83773g.o
>>   obj-$(CONFIG_SENSORS_W83792D) += w83792d.o
>>   obj-$(CONFIG_SENSORS_W83793)  += w83793.o
>>   obj-$(CONFIG_SENSORS_W83795)  += w83795.o
>> diff --git a/drivers/hwmon/w83773g.c b/drivers/hwmon/w83773g.c
>> new file mode 100644
>> index 0000000..d352bac
>> --- /dev/null
>> +++ b/drivers/hwmon/w83773g.c
>> @@ -0,0 +1,281 @@
>> +/*
>> + * Copyright (C) 2017 IBM Corp.
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation; either version 2 of the License, or
>> + * (at your option) any later version.
>> + *
>> + * Driver for the Nuvoton W83773G SMBus temperature sensor IC.
>> + * Supported models: W83773G
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/init.h>
>> +#include <linux/i2c.h>
>> +#include <linux/hwmon.h>
>> +#include <linux/hwmon-sysfs.h>
>> +#include <linux/err.h>
>> +#include <linux/of_device.h>
>> +#include <linux/regmap.h>
>> +
>> +/* Addresses to scan */
>> +static const unsigned short normal_i2c[] = { 0x4c, 0x4d, I2C_CLIENT_END
>> };
>> +
>> +/* The W83773 registers */
>> +#define W83773_CONVERSION_RATE_REG_READ                0x04
>> +#define W83773_CONVERSION_RATE_REG_WRITE       0x0A
>> +#define W83773_MANUFACTURER_ID_REG             0xFE
>> +#define W83773_LOCAL_TEMP                      0x00
>> +
>> +static const u8 W83773_STATUS[2] = { 0x02, 0x17 };
>> +
>> +static const u8 W83773_TEMP_LSB[2] = { 0x10, 0x25 };
>> +static const u8 W83773_TEMP_MSB[2] = { 0x01, 0x24 };
>> +
>> +static const u8 W83773_OFFSET_LSB[2] = { 0x12, 0x16 };
>> +static const u8 W83773_OFFSET_MSB[2] = { 0x11, 0x15 };
>> +
>> +
>> +/* this is the number of sensors in the device */
>> +static const struct i2c_device_id w83773_id[] = {
>> +       { "w83773g" },
>> +       { }
>> +};
>> +
>> +MODULE_DEVICE_TABLE(i2c, w83773_id);
>> +
>> +static const struct of_device_id w83773_of_match[] = {
>> +       {
>> +               .compatible = "nuvoton,w83773g"
>> +       },
>> +       { },
>> +};
>> +MODULE_DEVICE_TABLE(of, w83773_of_match);
>> +
>> +static inline int temp_of_local(s8 reg)
>> +{
>> +       return reg * 1000;
>> +}
>> +
>> +static inline int temp_of_remote(s8 hb, u8 lb)
>> +{
>> +       return (hb << 3 | lb >> 5) * 125;
>> +}
>> +
>> +static ssize_t show_local_temp(struct device *dev,
>> +                              struct device_attribute *attr,
>> +                              char *buf)
>> +{
>> +       struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned int regval;
>> +       int ret;
>> +
>> +       ret = regmap_read(regmap, sda->index, &regval);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       return sprintf(buf, "%d\n", temp_of_local(regval));
>> +}
>> +
>> +static ssize_t show_remote_temp(struct device *dev,
>> +                               struct device_attribute *attr,
>> +                               char *buf)
>> +{
>> +       struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned int regval_high;
>> +       unsigned int regval_low;
>> +       int ret;
>> +
>> +       ret = regmap_read(regmap, W83773_TEMP_MSB[sda->index],
>> &regval_high);
>> +       ret |= regmap_read(regmap, W83773_TEMP_LSB[sda->index],
>> &regval_low);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       return sprintf(buf, "%d\n", temp_of_remote(regval_high,
>> regval_low));
>> +}
>> +
>> +static ssize_t show_status(struct device *dev,
>> +                          struct device_attribute *attr,
>> +                          char *buf)
>> +{
>> +       struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned int regval;
>> +       int ret;
>> +
>> +       ret = regmap_read(regmap, W83773_STATUS[sda->index], &regval);
>> +
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       return sprintf(buf, "%d\n", (u8)regval & 0x04 >> 2);
>> +}
>> +
>> +static ssize_t show_offset(struct device *dev,
>> +                          struct device_attribute *attr,
>> +                          char *buf)
>> +{
>> +       struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned int regval_high;
>> +       unsigned int regval_low;
>> +       int ret;
>> +
>> +       ret = regmap_read(regmap, W83773_OFFSET_MSB[sda->index],
>> &regval_high);
>> +       ret |= regmap_read(regmap, W83773_OFFSET_LSB[sda->index],
>> &regval_low);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       return sprintf(buf, "%d\n", temp_of_remote(regval_high,
>> regval_low));
>> +}
>> +
>> +static ssize_t set_offset(struct device *dev,
>> +                         struct device_attribute *attr,
>> +                         const char *buf, size_t count)
>> +{
>> +       struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       long val;
>> +       int ret;
>> +       int err;
>> +       u8 high_byte;
>> +       u8 low_byte;
>> +
>> +       err = kstrtol(buf, 10, &val);
>> +       if (err)
>> +               return err;
>> +
>> +       val = clamp_val(val, -127825, 127825);
>> +       /* offset value equals to (high_byte << 3 | low_byte >> 5) * 125
>> */
>> +       val /= 125;
>> +       high_byte = val >> 3;
>> +       low_byte = (val & 0x07) << 5;
>> +
>> +       ret = regmap_write(regmap, W83773_OFFSET_MSB[sda->index],
>> high_byte);
>> +       ret |= regmap_write(regmap, W83773_OFFSET_LSB[sda->index],
>> low_byte);
>
>
> Please don't do that. The errors, if any, might be different, messing up
> the error return.

OK, it will be fixed in v3.

>
>
>> +
>> +       if (ret < 0)
>> +               return ret;
>> +       return count;
>> +}
>> +
>> +static ssize_t show_update_interval(struct device *dev,
>> +                                   struct device_attribute *attr,
>> +                                   char *buf)
>> +{
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned int regval;
>> +       int ret;
>> +
>> +       ret = regmap_read(regmap, W83773_CONVERSION_RATE_REG_READ,
>> &regval);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       return sprintf(buf, "%u\n", 16000 >> regval);
>> +}
>> +
>> +static ssize_t set_update_interval(struct device *dev,
>> +                                  struct device_attribute *attr,
>> +                                  const char *buf, size_t count)
>> +{
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned long val;
>> +       int ret;
>> +       int err, rate;
>> +
>> +       err = kstrtoul(buf, 10, &val);
>> +       if (err)
>> +               return err;
>> +
>> +       /*
>> +        * For valid rates, interval can be calculated as
>> +        *      interval = (1 << (8 - rate)) * 62.5;
>> +        * Rounded rate is therefore
>> +        *      rate = 8 - __fls(interval * 8 / (62.5 * 7));
>> +        * Use clamp_val() to avoid overflows, and to ensure valid input
>> +        * for __fls.
>> +        */
>> +       val = clamp_val(val, 62, 16000) * 10;
>> +       rate = 8 - __fls((val * 8 / (625 * 7)));
>> +       ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE,
>> rate);
>> +       if (ret < 0)
>> +               return ret;
>> +       return count;
>> +}
>> +
>> +static SENSOR_DEVICE_ATTR(temp1_input, 0444, show_local_temp, NULL,
>> +                         W83773_LOCAL_TEMP);
>> +static SENSOR_DEVICE_ATTR(temp2_input, 0444, show_remote_temp, NULL, 0);
>> +static SENSOR_DEVICE_ATTR(temp2_fault, 0444, show_status, NULL, 0);
>> +static SENSOR_DEVICE_ATTR(temp2_offset, 0644, show_offset, set_offset,
>> 0);
>> +static SENSOR_DEVICE_ATTR(temp3_input, 0444, show_remote_temp, NULL, 1);
>> +static SENSOR_DEVICE_ATTR(temp3_fault, 0444, show_status, NULL, 1);
>> +static SENSOR_DEVICE_ATTR(temp3_offset, 0644, show_offset, set_offset,
>> 1);
>> +static DEVICE_ATTR(update_interval, 0644, show_update_interval,
>> +                  set_update_interval);
>> +
>> +static struct attribute *w83773g_attrs[] = {
>> +       &sensor_dev_attr_temp1_input.dev_attr.attr,
>> +       &sensor_dev_attr_temp2_input.dev_attr.attr,
>> +       &sensor_dev_attr_temp2_fault.dev_attr.attr,
>> +       &sensor_dev_attr_temp2_offset.dev_attr.attr,
>> +       &sensor_dev_attr_temp3_input.dev_attr.attr,
>> +       &sensor_dev_attr_temp3_fault.dev_attr.attr,
>> +       &sensor_dev_attr_temp3_offset.dev_attr.attr,
>> +       &dev_attr_update_interval.attr,
>> +       NULL
>> +};
>> +ATTRIBUTE_GROUPS(w83773g);
>> +
>> +static const struct regmap_config w83773g_regmap_config = {
>> +       .reg_bits = 8,
>> +       .val_bits = 8,
>> +};
>> +
>> +static int w83773_probe(struct i2c_client *client,
>> +                       const struct i2c_device_id *id)
>> +{
>> +
>> +       struct device *dev = &client->dev;
>> +       struct device *hwmon_dev;
>> +       struct regmap *regmap;
>> +       int ret;
>> +
>> +       regmap = devm_regmap_init_i2c(client, &w83773g_regmap_config);
>> +       if (IS_ERR(regmap)) {
>> +               dev_err(dev, "failed to allocate register map\n");
>> +               return PTR_ERR(regmap);
>> +       }
>> +
>> +       /* Set the conversion rate to 2 Hz */
>> +       ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE,
>> 0x05);
>> +       if (ret < 0) {
>> +               dev_err(&client->dev, "error writing config rate
>> register\n");
>> +               return ret;
>> +       }
>> +
>> +       i2c_set_clientdata(client, regmap);
>> +       hwmon_dev = devm_hwmon_device_register_with_groups(dev,
>> client->name,
>> +                                                     regmap,
>> w83773g_groups);
>
>
> You lost me here. Why did you stop using the new API ?

I was referencing some other hwmon driver (e.g. tmp401.c) and find out
the usage of SENSOR_DEVICE_ATTR, which I feel more clear and straightforward.

So what I know for know is:
1. In v1, devm_hwmon_device_register_with_info() with hwmon_chip_info providing
is_visible(), read/write() operations;
2. In v2, devm_hwmon_device_register_with_groups() with attribute_group.

So from your suggestion, it seems the hwmon_chip_info is more preferable, is it?
If yes, I will update this in v3 as well.

Thanks!
>
> Guenter
>
>
>> +       return PTR_ERR_OR_ZERO(hwmon_dev);
>> +}
>> +
>> +static struct i2c_driver w83773_driver = {
>> +       .class = I2C_CLASS_HWMON,
>> +       .driver = {
>> +               .name   = "w83773g",
>> +               .of_match_table = of_match_ptr(w83773_of_match),
>> +       },
>> +       .probe = w83773_probe,
>> +       .id_table = w83773_id,
>> +       .address_list = normal_i2c,
>> +};
>> +
>> +module_i2c_driver(w83773_driver);
>> +
>> +MODULE_AUTHOR("Lei YU <mine260309@gmail.com>");
>> +MODULE_DESCRIPTION("W83773G temperature sensor driver");
>> +MODULE_LICENSE("GPL");
>>
>

Re: [PATCH v2 2/3] drivers: hwmon: Add W83773G driver

[Lei YU]

On Tue, Nov 7, 2017 at 10:33 PM, Guenter Roeck <linux-0h96xk9xTtrk1uMJSBkQmQ@public.gmane.org> wrote:
> On 11/07/2017 12:27 AM, Lei YU wrote:
>>
>> Nuvoton W83773G is a hardware monitor IC providing one local
>> temperature and two remote temperature sensors.
>>
>> Signed-off-by: Lei YU <mine260309-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>> ---
>> v2:
>>   - Rewrite the driver using regmap
>>   - Add offset and update_interval
>> ---
>>   drivers/hwmon/Kconfig   |  10 ++
>>   drivers/hwmon/Makefile  |   1 +
>>   drivers/hwmon/w83773g.c | 281
>> ++++++++++++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 292 insertions(+)
>>   create mode 100644 drivers/hwmon/w83773g.c
>>
>> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
>> index d654314..11c6248 100644
>> --- a/drivers/hwmon/Kconfig
>> +++ b/drivers/hwmon/Kconfig
>> @@ -1710,6 +1710,16 @@ config SENSORS_VT8231
>>           This driver can also be built as a module.  If so, the module
>>           will be called vt8231.
>>   +config SENSORS_W83773G
>> +       tristate "Nuvoton W83773G"
>> +       depends on I2C
>> +       help
>> +         If you say yes here you get support for the Nuvoton W83773G
>> hardware
>> +         monitoring chip.
>> +
>> +         This driver can also be built as a module.  If so, the module
>> +         will be called w83773g.
>> +
>>   config SENSORS_W83781D
>>         tristate "Winbond W83781D, W83782D, W83783S, Asus AS99127F"
>>         depends on I2C
>> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
>> index c84d978..0649ad8 100644
>> --- a/drivers/hwmon/Makefile
>> +++ b/drivers/hwmon/Makefile
>> @@ -13,6 +13,7 @@ obj-$(CONFIG_SENSORS_ATK0110) += asus_atk0110.o
>>   # asb100, then w83781d go first, as they can override other drivers'
>> addresses.
>>   obj-$(CONFIG_SENSORS_ASB100)  += asb100.o
>>   obj-$(CONFIG_SENSORS_W83627HF)        += w83627hf.o
>> +obj-$(CONFIG_SENSORS_W83773G)  += w83773g.o
>>   obj-$(CONFIG_SENSORS_W83792D) += w83792d.o
>>   obj-$(CONFIG_SENSORS_W83793)  += w83793.o
>>   obj-$(CONFIG_SENSORS_W83795)  += w83795.o
>> diff --git a/drivers/hwmon/w83773g.c b/drivers/hwmon/w83773g.c
>> new file mode 100644
>> index 0000000..d352bac
>> --- /dev/null
>> +++ b/drivers/hwmon/w83773g.c
>> @@ -0,0 +1,281 @@
>> +/*
>> + * Copyright (C) 2017 IBM Corp.
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation; either version 2 of the License, or
>> + * (at your option) any later version.
>> + *
>> + * Driver for the Nuvoton W83773G SMBus temperature sensor IC.
>> + * Supported models: W83773G
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/init.h>
>> +#include <linux/i2c.h>
>> +#include <linux/hwmon.h>
>> +#include <linux/hwmon-sysfs.h>
>> +#include <linux/err.h>
>> +#include <linux/of_device.h>
>> +#include <linux/regmap.h>
>> +
>> +/* Addresses to scan */
>> +static const unsigned short normal_i2c[] = { 0x4c, 0x4d, I2C_CLIENT_END
>> };
>> +
>> +/* The W83773 registers */
>> +#define W83773_CONVERSION_RATE_REG_READ                0x04
>> +#define W83773_CONVERSION_RATE_REG_WRITE       0x0A
>> +#define W83773_MANUFACTURER_ID_REG             0xFE
>> +#define W83773_LOCAL_TEMP                      0x00
>> +
>> +static const u8 W83773_STATUS[2] = { 0x02, 0x17 };
>> +
>> +static const u8 W83773_TEMP_LSB[2] = { 0x10, 0x25 };
>> +static const u8 W83773_TEMP_MSB[2] = { 0x01, 0x24 };
>> +
>> +static const u8 W83773_OFFSET_LSB[2] = { 0x12, 0x16 };
>> +static const u8 W83773_OFFSET_MSB[2] = { 0x11, 0x15 };
>> +
>> +
>> +/* this is the number of sensors in the device */
>> +static const struct i2c_device_id w83773_id[] = {
>> +       { "w83773g" },
>> +       { }
>> +};
>> +
>> +MODULE_DEVICE_TABLE(i2c, w83773_id);
>> +
>> +static const struct of_device_id w83773_of_match[] = {
>> +       {
>> +               .compatible = "nuvoton,w83773g"
>> +       },
>> +       { },
>> +};
>> +MODULE_DEVICE_TABLE(of, w83773_of_match);
>> +
>> +static inline int temp_of_local(s8 reg)
>> +{
>> +       return reg * 1000;
>> +}
>> +
>> +static inline int temp_of_remote(s8 hb, u8 lb)
>> +{
>> +       return (hb << 3 | lb >> 5) * 125;
>> +}
>> +
>> +static ssize_t show_local_temp(struct device *dev,
>> +                              struct device_attribute *attr,
>> +                              char *buf)
>> +{
>> +       struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned int regval;
>> +       int ret;
>> +
>> +       ret = regmap_read(regmap, sda->index, &regval);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       return sprintf(buf, "%d\n", temp_of_local(regval));
>> +}
>> +
>> +static ssize_t show_remote_temp(struct device *dev,
>> +                               struct device_attribute *attr,
>> +                               char *buf)
>> +{
>> +       struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned int regval_high;
>> +       unsigned int regval_low;
>> +       int ret;
>> +
>> +       ret = regmap_read(regmap, W83773_TEMP_MSB[sda->index],
>> &regval_high);
>> +       ret |= regmap_read(regmap, W83773_TEMP_LSB[sda->index],
>> &regval_low);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       return sprintf(buf, "%d\n", temp_of_remote(regval_high,
>> regval_low));
>> +}
>> +
>> +static ssize_t show_status(struct device *dev,
>> +                          struct device_attribute *attr,
>> +                          char *buf)
>> +{
>> +       struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned int regval;
>> +       int ret;
>> +
>> +       ret = regmap_read(regmap, W83773_STATUS[sda->index], &regval);
>> +
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       return sprintf(buf, "%d\n", (u8)regval & 0x04 >> 2);
>> +}
>> +
>> +static ssize_t show_offset(struct device *dev,
>> +                          struct device_attribute *attr,
>> +                          char *buf)
>> +{
>> +       struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned int regval_high;
>> +       unsigned int regval_low;
>> +       int ret;
>> +
>> +       ret = regmap_read(regmap, W83773_OFFSET_MSB[sda->index],
>> &regval_high);
>> +       ret |= regmap_read(regmap, W83773_OFFSET_LSB[sda->index],
>> &regval_low);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       return sprintf(buf, "%d\n", temp_of_remote(regval_high,
>> regval_low));
>> +}
>> +
>> +static ssize_t set_offset(struct device *dev,
>> +                         struct device_attribute *attr,
>> +                         const char *buf, size_t count)
>> +{
>> +       struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       long val;
>> +       int ret;
>> +       int err;
>> +       u8 high_byte;
>> +       u8 low_byte;
>> +
>> +       err = kstrtol(buf, 10, &val);
>> +       if (err)
>> +               return err;
>> +
>> +       val = clamp_val(val, -127825, 127825);
>> +       /* offset value equals to (high_byte << 3 | low_byte >> 5) * 125
>> */
>> +       val /= 125;
>> +       high_byte = val >> 3;
>> +       low_byte = (val & 0x07) << 5;
>> +
>> +       ret = regmap_write(regmap, W83773_OFFSET_MSB[sda->index],
>> high_byte);
>> +       ret |= regmap_write(regmap, W83773_OFFSET_LSB[sda->index],
>> low_byte);
>
>
> Please don't do that. The errors, if any, might be different, messing up
> the error return.

OK, it will be fixed in v3.

>
>
>> +
>> +       if (ret < 0)
>> +               return ret;
>> +       return count;
>> +}
>> +
>> +static ssize_t show_update_interval(struct device *dev,
>> +                                   struct device_attribute *attr,
>> +                                   char *buf)
>> +{
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned int regval;
>> +       int ret;
>> +
>> +       ret = regmap_read(regmap, W83773_CONVERSION_RATE_REG_READ,
>> &regval);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       return sprintf(buf, "%u\n", 16000 >> regval);
>> +}
>> +
>> +static ssize_t set_update_interval(struct device *dev,
>> +                                  struct device_attribute *attr,
>> +                                  const char *buf, size_t count)
>> +{
>> +       struct regmap *regmap = dev_get_drvdata(dev);
>> +       unsigned long val;
>> +       int ret;
>> +       int err, rate;
>> +
>> +       err = kstrtoul(buf, 10, &val);
>> +       if (err)
>> +               return err;
>> +
>> +       /*
>> +        * For valid rates, interval can be calculated as
>> +        *      interval = (1 << (8 - rate)) * 62.5;
>> +        * Rounded rate is therefore
>> +        *      rate = 8 - __fls(interval * 8 / (62.5 * 7));
>> +        * Use clamp_val() to avoid overflows, and to ensure valid input
>> +        * for __fls.
>> +        */
>> +       val = clamp_val(val, 62, 16000) * 10;
>> +       rate = 8 - __fls((val * 8 / (625 * 7)));
>> +       ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE,
>> rate);
>> +       if (ret < 0)
>> +               return ret;
>> +       return count;
>> +}
>> +
>> +static SENSOR_DEVICE_ATTR(temp1_input, 0444, show_local_temp, NULL,
>> +                         W83773_LOCAL_TEMP);
>> +static SENSOR_DEVICE_ATTR(temp2_input, 0444, show_remote_temp, NULL, 0);
>> +static SENSOR_DEVICE_ATTR(temp2_fault, 0444, show_status, NULL, 0);
>> +static SENSOR_DEVICE_ATTR(temp2_offset, 0644, show_offset, set_offset,
>> 0);
>> +static SENSOR_DEVICE_ATTR(temp3_input, 0444, show_remote_temp, NULL, 1);
>> +static SENSOR_DEVICE_ATTR(temp3_fault, 0444, show_status, NULL, 1);
>> +static SENSOR_DEVICE_ATTR(temp3_offset, 0644, show_offset, set_offset,
>> 1);
>> +static DEVICE_ATTR(update_interval, 0644, show_update_interval,
>> +                  set_update_interval);
>> +
>> +static struct attribute *w83773g_attrs[] = {
>> +       &sensor_dev_attr_temp1_input.dev_attr.attr,
>> +       &sensor_dev_attr_temp2_input.dev_attr.attr,
>> +       &sensor_dev_attr_temp2_fault.dev_attr.attr,
>> +       &sensor_dev_attr_temp2_offset.dev_attr.attr,
>> +       &sensor_dev_attr_temp3_input.dev_attr.attr,
>> +       &sensor_dev_attr_temp3_fault.dev_attr.attr,
>> +       &sensor_dev_attr_temp3_offset.dev_attr.attr,
>> +       &dev_attr_update_interval.attr,
>> +       NULL
>> +};
>> +ATTRIBUTE_GROUPS(w83773g);
>> +
>> +static const struct regmap_config w83773g_regmap_config = {
>> +       .reg_bits = 8,
>> +       .val_bits = 8,
>> +};
>> +
>> +static int w83773_probe(struct i2c_client *client,
>> +                       const struct i2c_device_id *id)
>> +{
>> +
>> +       struct device *dev = &client->dev;
>> +       struct device *hwmon_dev;
>> +       struct regmap *regmap;
>> +       int ret;
>> +
>> +       regmap = devm_regmap_init_i2c(client, &w83773g_regmap_config);
>> +       if (IS_ERR(regmap)) {
>> +               dev_err(dev, "failed to allocate register map\n");
>> +               return PTR_ERR(regmap);
>> +       }
>> +
>> +       /* Set the conversion rate to 2 Hz */
>> +       ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE,
>> 0x05);
>> +       if (ret < 0) {
>> +               dev_err(&client->dev, "error writing config rate
>> register\n");
>> +               return ret;
>> +       }
>> +
>> +       i2c_set_clientdata(client, regmap);
>> +       hwmon_dev = devm_hwmon_device_register_with_groups(dev,
>> client->name,
>> +                                                     regmap,
>> w83773g_groups);
>
>
> You lost me here. Why did you stop using the new API ?

I was referencing some other hwmon driver (e.g. tmp401.c) and find out
the usage of SENSOR_DEVICE_ATTR, which I feel more clear and straightforward.

So what I know for know is:
1. In v1, devm_hwmon_device_register_with_info() with hwmon_chip_info providing
is_visible(), read/write() operations;
2. In v2, devm_hwmon_device_register_with_groups() with attribute_group.

So from your suggestion, it seems the hwmon_chip_info is more preferable, is it?
If yes, I will update this in v3 as well.

Thanks!
>
> Guenter
>
>
>> +       return PTR_ERR_OR_ZERO(hwmon_dev);
>> +}
>> +
>> +static struct i2c_driver w83773_driver = {
>> +       .class = I2C_CLASS_HWMON,
>> +       .driver = {
>> +               .name   = "w83773g",
>> +               .of_match_table = of_match_ptr(w83773_of_match),
>> +       },
>> +       .probe = w83773_probe,
>> +       .id_table = w83773_id,
>> +       .address_list = normal_i2c,
>> +};
>> +
>> +module_i2c_driver(w83773_driver);
>> +
>> +MODULE_AUTHOR("Lei YU <mine260309-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>");
>> +MODULE_DESCRIPTION("W83773G temperature sensor driver");
>> +MODULE_LICENSE("GPL");
>>
>
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Re: [PATCH v2 2/3] drivers: hwmon: Add W83773G driver

[Guenter Roeck]

On Wed, Nov 08, 2017 at 02:03:34PM +0800, Lei YU wrote:
> On Tue, Nov 7, 2017 at 10:33 PM, Guenter Roeck <linux@roeck-us.net> wrote:
> > On 11/07/2017 12:27 AM, Lei YU wrote:
> >>
> >> Nuvoton W83773G is a hardware monitor IC providing one local
> >> temperature and two remote temperature sensors.
> >>
> >> Signed-off-by: Lei YU <mine260309@gmail.com>
> >> ---
> >> v2:
> >>   - Rewrite the driver using regmap
> >>   - Add offset and update_interval
[ ... ]

> >> +       hwmon_dev = devm_hwmon_device_register_with_groups(dev,
> >> client->name,
> >> +                                                     regmap,
> >> w83773g_groups);
> >
> >
> > You lost me here. Why did you stop using the new API ?
> 
> I was referencing some other hwmon driver (e.g. tmp401.c) and find out
> the usage of SENSOR_DEVICE_ATTR, which I feel more clear and straightforward.
> 

The new API is supposed to replace the old API to make it independent from
sysfs and to simplify the actual driver code. On a driver like this, using
the new API should reduce code and data size by 30% or more.

If you find the new API to be less clear and less straigtforward to use than
the old API, we need to improve it. Do you have any suggestions ?

Thanks,
Guenter

Re: [PATCH v2 2/3] drivers: hwmon: Add W83773G driver

[Lei YU]

On Thu, Nov 9, 2017 at 1:59 AM, Guenter Roeck <linux@roeck-us.net> wrote:
> On Wed, Nov 08, 2017 at 02:03:34PM +0800, Lei YU wrote:
>> On Tue, Nov 7, 2017 at 10:33 PM, Guenter Roeck <linux@roeck-us.net> wrote:
>> > On 11/07/2017 12:27 AM, Lei YU wrote:
>> >>
>> >> Nuvoton W83773G is a hardware monitor IC providing one local
>> >> temperature and two remote temperature sensors.
>> >>
>> >> Signed-off-by: Lei YU <mine260309@gmail.com>
>> >> ---
>> >> v2:
>> >>   - Rewrite the driver using regmap
>> >>   - Add offset and update_interval
> [ ... ]
>
>> >> +       hwmon_dev = devm_hwmon_device_register_with_groups(dev,
>> >> client->name,
>> >> +                                                     regmap,
>> >> w83773g_groups);
>> >
>> >
>> > You lost me here. Why did you stop using the new API ?
>>
>> I was referencing some other hwmon driver (e.g. tmp401.c) and find out
>> the usage of SENSOR_DEVICE_ATTR, which I feel more clear and straightforward.
>>
>
> The new API is supposed to replace the old API to make it independent from
> sysfs and to simplify the actual driver code. On a driver like this, using
> the new API should reduce code and data size by 30% or more.
>
> If you find the new API to be less clear and less straigtforward to use than
> the old API, we need to improve it. Do you have any suggestions ?
>

Thanks for the explanation.
I have sent the v3 patch using the new API.
And I do compare the binary size and it is smaller with the new API, great!

> Thanks,
> Guenter