[PATCH v3 1/3] hwmon: ltc2990: refactor value conversion

[PATCH v3 1/3] hwmon: ltc2990: refactor value conversion

[Tom Levens]

Conversion from raw values to signed integers has been refactored using
bitops.h. This also fixes a bug where negative temperatures were
converted incorrectly.

Signed-off-by: Tom Levens <tom.levens@cern.ch>
---
 drivers/hwmon/ltc2990.c | 18 ++++--------------
 1 file changed, 4 insertions(+), 14 deletions(-)

diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c
index 8f8fe05..e320d21 100644
--- a/drivers/hwmon/ltc2990.c
+++ b/drivers/hwmon/ltc2990.c
@@ -11,6 +11,7 @@
  * the chip's internal temperature and Vcc power supply voltage.
  */
 
+#include <linux/bitops.h>
 #include <linux/err.h>
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
@@ -34,15 +35,6 @@
 #define LTC2990_CONTROL_MODE_CURRENT	0x06
 #define LTC2990_CONTROL_MODE_VOLTAGE	0x07
 
-/* convert raw register value to sign-extended integer in 16-bit range */
-static int ltc2990_voltage_to_int(int raw)
-{
-	if (raw & BIT(14))
-		return -(0x4000 - (raw & 0x3FFF)) << 2;
-	else
-		return (raw & 0x3FFF) << 2;
-}
-
 /* Return the converted value from the given register in uV or mC */
 static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
 {
@@ -55,18 +47,16 @@ static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
 	switch (reg) {
 	case LTC2990_TINT_MSB:
 		/* internal temp, 0.0625 degrees/LSB, 13-bit  */
-		val = (val & 0x1FFF) << 3;
-		*result = (val * 1000) >> 7;
+		*result = sign_extend32(val, 12) * 1000 / 16;
 		break;
 	case LTC2990_V1_MSB:
 	case LTC2990_V3_MSB:
 		 /* Vx-Vy, 19.42uV/LSB. Depends on mode. */
-		*result = ltc2990_voltage_to_int(val) * 1942 / (4 * 100);
+		*result = sign_extend32(val, 14) * 1942 / 100;
 		break;
 	case LTC2990_VCC_MSB:
 		/* Vcc, 305.18μV/LSB, 2.5V offset */
-		*result = (ltc2990_voltage_to_int(val) * 30518 /
-			   (4 * 100 * 1000)) + 2500;
+		*result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500;
 		break;
 	default:
 		return -EINVAL; /* won't happen, keep compiler happy */
-- 
1.8.3.1

[PATCH v3 2/3] hwmon: ltc2990: add devicetree binding

[Tom Levens]

Add a devicetree binding for the ltc2990 hwmon driver.

Signed-off-by: Tom Levens <tom.levens@cern.ch>
---
 .../devicetree/bindings/hwmon/ltc2990.txt          | 36 ++++++++++++++++++++++
 1 file changed, 36 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwmon/ltc2990.txt

diff --git a/Documentation/devicetree/bindings/hwmon/ltc2990.txt b/Documentation/devicetree/bindings/hwmon/ltc2990.txt
new file mode 100644
index 0000000..f92f540
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/ltc2990.txt
@@ -0,0 +1,36 @@
+ltc2990: Linear Technology LTC2990 power monitor
+
+Required properties:
+- compatible: Must be "lltc,ltc2990"
+- reg: I2C slave address
+- lltc,meas-mode:
+	An array of two integers for configuring the chip measurement mode.
+
+	The first integer defines the bits 2..0 in the control register. In all
+	cases the internal temperature and supply voltage are measured. In
+	addition the following input measurements are enabled per mode:
+
+		0: V1, V2, TR2
+		1: V1-V2, TR2
+		2: V1-V2, V3, V4
+		3: TR1, V3, V4
+		4: TR1, V3-V4
+		5: TR1, TR2
+		6: V1-V2, V3-V4
+		7: V1, V2, V3, V4
+
+	The second integer defines the bits 4..3 in the control register. This
+	allows a subset of the measurements to be enabled:
+
+		0: Internal temperature and supply voltage only
+		1: TR1, V1 or V1-V2 only per mode
+		2: TR2, V3 or V3-V4 only per mode
+		3: All measurements per mode
+
+Example:
+
+ltc2990@4c {
+	compatible = "lltc,ltc2990";
+	reg = <0x4c>;
+	lltc,meas-mode = <7 3>;	/* V1, V2, V3, V4 */
+};
-- 
1.8.3.1

Re: [PATCH v3 2/3] hwmon: ltc2990: add devicetree binding

[Rob Herring]

On Mon, Jul 03, 2017 at 06:28:59AM +0200, Tom Levens wrote:
> Add a devicetree binding for the ltc2990 hwmon driver.

Bindings are for a device, not a Linux driver.

> 
> Signed-off-by: Tom Levens <tom.levens@cern.ch>
> ---
>  .../devicetree/bindings/hwmon/ltc2990.txt          | 36 ++++++++++++++++++++++
>  1 file changed, 36 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/hwmon/ltc2990.txt

Otherwise,

Acked-by: Rob Herring <robh@kernel.org>

[PATCH v3 3/3] hwmon: ltc2990: support all measurement modes

[Tom Levens]

Updated version of the ltc2990 driver which supports all measurement
modes (current, voltage, temperature) available in the chip.

If devicetree is used, the mode must be specified with the property
"lltc,meas-mode". The format and possible values of the property are
described in the binding.

If devicetree is not used, the mode of the chip will not be configured.
Unless the chip is configured by another source, only the internal
temperature and supply voltage will be measured.

Signed-off-by: Tom Levens <tom.levens@cern.ch>
---
 Documentation/hwmon/ltc2990 |  24 ++++--
 drivers/hwmon/Kconfig       |   7 +-
 drivers/hwmon/ltc2990.c     | 196 +++++++++++++++++++++++++++++++++++++-------
 3 files changed, 185 insertions(+), 42 deletions(-)

diff --git a/Documentation/hwmon/ltc2990 b/Documentation/hwmon/ltc2990
index c25211e..3ed68f6 100644
--- a/Documentation/hwmon/ltc2990
+++ b/Documentation/hwmon/ltc2990
@@ -8,6 +8,7 @@ Supported chips:
     Datasheet: http://www.linear.com/product/ltc2990
 
 Author: Mike Looijmans <mike.looijmans@topic.nl>
+        Tom Levens <tom.levens@cern.ch>
 
 
 Description
@@ -16,10 +17,8 @@ Description
 LTC2990 is a Quad I2C Voltage, Current and Temperature Monitor.
 The chip's inputs can measure 4 voltages, or two inputs together (1+2 and 3+4)
 can be combined to measure a differential voltage, which is typically used to
-measure current through a series resistor, or a temperature.
-
-This driver currently uses the 2x differential mode only. In order to support
-other modes, the driver will need to be expanded.
+measure current through a series resistor, or a temperature with an external
+diode.
 
 
 Usage Notes
@@ -32,12 +31,19 @@ devices explicitly.
 Sysfs attributes
 ----------------
 
+in0_input     Voltage at Vcc pin in millivolt (range 2.5V to 5V)
+temp1_input   Internal chip temperature in millidegrees Celcius
+
+A subset of the following attributes are visible, depending on the measurement
+mode of the chip.
+
+in[1-4]_input Voltage at V[1-4] pin in millivolt
+temp2_input   External temperature sensor TR1 in millidegrees Celcius
+temp3_input   External temperature sensor TR2 in millidegrees Celcius
+curr1_input   Current in mA across V1-V2 assuming a 1mOhm sense resistor
+curr2_input   Current in mA across V3-V4 assuming a 1mOhm sense resistor
+
 The "curr*_input" measurements actually report the voltage drop across the
 input pins in microvolts. This is equivalent to the current through a 1mOhm
 sense resistor. Divide the reported value by the actual sense resistor value
 in mOhm to get the actual value.
-
-in0_input     Voltage at Vcc pin in millivolt (range 2.5V to 5V)
-temp1_input   Internal chip temperature in millidegrees Celcius
-curr1_input   Current in mA across v1-v2 assuming a 1mOhm sense resistor.
-curr2_input   Current in mA across v3-v4 assuming a 1mOhm sense resistor.
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 5ef2814..578e5a9 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -709,15 +709,12 @@ config SENSORS_LTC2945
 	  be called ltc2945.
 
 config SENSORS_LTC2990
-	tristate "Linear Technology LTC2990 (current monitoring mode only)"
+	tristate "Linear Technology LTC2990"
 	depends on I2C
 	help
 	  If you say yes here you get support for Linear Technology LTC2990
 	  I2C System Monitor. The LTC2990 supports a combination of voltage,
-	  current and temperature monitoring, but in addition to the Vcc supply
-	  voltage and chip temperature, this driver currently only supports
-	  reading two currents by measuring two differential voltages across
-	  series resistors.
+	  current and temperature monitoring.
 
 	  This driver can also be built as a module. If so, the module will
 	  be called ltc2990.
diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c
index e320d21..32f3a8d 100644
--- a/drivers/hwmon/ltc2990.c
+++ b/drivers/hwmon/ltc2990.c
@@ -5,10 +5,6 @@
  * Author: Mike Looijmans <mike.looijmans@topic.nl>
  *
  * License: GPLv2
- *
- * This driver assumes the chip is wired as a dual current monitor, and
- * reports the voltage drop across two series resistors. It also reports
- * the chip's internal temperature and Vcc power supply voltage.
  */
 
 #include <linux/bitops.h>
@@ -18,6 +14,7 @@
 #include <linux/i2c.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/of.h>
 
 #define LTC2990_STATUS	0x00
 #define LTC2990_CONTROL	0x01
@@ -29,35 +26,109 @@
 #define LTC2990_V4_MSB	0x0C
 #define LTC2990_VCC_MSB	0x0E
 
-#define LTC2990_CONTROL_KELVIN		BIT(7)
-#define LTC2990_CONTROL_SINGLE		BIT(6)
-#define LTC2990_CONTROL_MEASURE_ALL	(0x3 << 3)
-#define LTC2990_CONTROL_MODE_CURRENT	0x06
-#define LTC2990_CONTROL_MODE_VOLTAGE	0x07
+#define LTC2990_IN0	BIT(0)
+#define LTC2990_IN1	BIT(1)
+#define LTC2990_IN2	BIT(2)
+#define LTC2990_IN3	BIT(3)
+#define LTC2990_IN4	BIT(4)
+#define LTC2990_CURR1	BIT(5)
+#define LTC2990_CURR2	BIT(6)
+#define LTC2990_TEMP1	BIT(7)
+#define LTC2990_TEMP2	BIT(8)
+#define LTC2990_TEMP3	BIT(9)
+#define LTC2990_NONE	0
+#define LTC2990_ALL	GENMASK(9, 0)
+
+#define LTC2990_MODE0_SHIFT	0
+#define LTC2990_MODE0_MASK	GENMASK(2, 0)
+#define LTC2990_MODE1_SHIFT	3
+#define LTC2990_MODE1_MASK	GENMASK(1, 0)
+
+/* Enabled measurements for mode bits 2..0 */
+static const int ltc2990_attrs_ena_0[] = {
+	LTC2990_IN1 | LTC2990_IN2 | LTC2990_TEMP3,
+	LTC2990_CURR1 | LTC2990_TEMP3,
+	LTC2990_CURR1 | LTC2990_IN3 | LTC2990_IN4,
+	LTC2990_TEMP2 | LTC2990_IN3 | LTC2990_IN4,
+	LTC2990_TEMP2 | LTC2990_CURR2,
+	LTC2990_TEMP2 | LTC2990_TEMP3,
+	LTC2990_CURR1 | LTC2990_CURR2,
+	LTC2990_IN1 | LTC2990_IN2 | LTC2990_IN3 | LTC2990_IN4
+};
+
+/* Enabled measurements for mode bits 4..3 */
+static const int ltc2990_attrs_ena_1[] = {
+	LTC2990_NONE,
+	LTC2990_TEMP2 | LTC2990_IN1 | LTC2990_CURR1,
+	LTC2990_TEMP3 | LTC2990_IN3 | LTC2990_CURR2,
+	LTC2990_ALL
+};
+
+struct ltc2990_data {
+	struct i2c_client *i2c;
+	u32 mode[2];
+};
 
 /* Return the converted value from the given register in uV or mC */
-static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
+static int ltc2990_get_value(struct i2c_client *i2c, int index, int *result)
 {
 	int val;
+	u8 reg;
+
+	switch (index) {
+	case LTC2990_IN0:
+		reg = LTC2990_VCC_MSB;
+		break;
+	case LTC2990_IN1:
+	case LTC2990_CURR1:
+	case LTC2990_TEMP2:
+		reg = LTC2990_V1_MSB;
+		break;
+	case LTC2990_IN2:
+		reg = LTC2990_V2_MSB;
+		break;
+	case LTC2990_IN3:
+	case LTC2990_CURR2:
+	case LTC2990_TEMP3:
+		reg = LTC2990_V3_MSB;
+		break;
+	case LTC2990_IN4:
+		reg = LTC2990_V4_MSB;
+		break;
+	case LTC2990_TEMP1:
+		reg = LTC2990_TINT_MSB;
+		break;
+	default:
+		return -EINVAL;
+	}
 
 	val = i2c_smbus_read_word_swapped(i2c, reg);
 	if (unlikely(val < 0))
 		return val;
 
-	switch (reg) {
-	case LTC2990_TINT_MSB:
-		/* internal temp, 0.0625 degrees/LSB, 13-bit  */
+	switch (index) {
+	case LTC2990_TEMP1:
+	case LTC2990_TEMP2:
+	case LTC2990_TEMP3:
+		/* temp, 0.0625 degrees/LSB */
 		*result = sign_extend32(val, 12) * 1000 / 16;
 		break;
-	case LTC2990_V1_MSB:
-	case LTC2990_V3_MSB:
-		 /* Vx-Vy, 19.42uV/LSB. Depends on mode. */
+	case LTC2990_CURR1:
+	case LTC2990_CURR2:
+		 /* Vx-Vy, 19.42uV/LSB */
 		*result = sign_extend32(val, 14) * 1942 / 100;
 		break;
-	case LTC2990_VCC_MSB:
-		/* Vcc, 305.18μV/LSB, 2.5V offset */
+	case LTC2990_IN0:
+		/* Vcc, 305.18uV/LSB, 2.5V offset */
 		*result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500;
 		break;
+	case LTC2990_IN1:
+	case LTC2990_IN2:
+	case LTC2990_IN3:
+	case LTC2990_IN4:
+		/* Vx, 305.18uV/LSB */
+		*result = sign_extend32(val, 14) * 30518 / (100 * 1000);
+		break;
 	default:
 		return -EINVAL; /* won't happen, keep compiler happy */
 	}
@@ -69,48 +140,117 @@ static ssize_t ltc2990_show_value(struct device *dev,
 				  struct device_attribute *da, char *buf)
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct ltc2990_data *data = dev_get_drvdata(dev);
 	int value;
 	int ret;
 
-	ret = ltc2990_get_value(dev_get_drvdata(dev), attr->index, &value);
+	ret = ltc2990_get_value(data->i2c, attr->index, &value);
 	if (unlikely(ret < 0))
 		return ret;
 
 	return snprintf(buf, PAGE_SIZE, "%d\n", value);
 }
 
+static umode_t ltc2990_attrs_visible(struct kobject *kobj,
+				     struct attribute *a, int n)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct ltc2990_data *data = dev_get_drvdata(dev);
+	struct device_attribute *da =
+			container_of(a, struct device_attribute, attr);
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+
+	int attrs_mask = LTC2990_IN0 | LTC2990_TEMP1 |
+			 ltc2990_attrs_ena_0[data->mode[0]] &
+			 ltc2990_attrs_ena_1[data->mode[1]];
+
+	if (attr->index & attrs_mask)
+		return a->mode;
+
+	return 0;
+}
+
 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ltc2990_show_value, NULL,
-			  LTC2990_TINT_MSB);
+			  LTC2990_TEMP1);
+static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, ltc2990_show_value, NULL,
+			  LTC2990_TEMP2);
+static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, ltc2990_show_value, NULL,
+			  LTC2990_TEMP3);
 static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ltc2990_show_value, NULL,
-			  LTC2990_V1_MSB);
+			  LTC2990_CURR1);
 static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO, ltc2990_show_value, NULL,
-			  LTC2990_V3_MSB);
+			  LTC2990_CURR2);
 static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ltc2990_show_value, NULL,
-			  LTC2990_VCC_MSB);
+			  LTC2990_IN0);
+static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ltc2990_show_value, NULL,
+			  LTC2990_IN1);
+static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, ltc2990_show_value, NULL,
+			  LTC2990_IN2);
+static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, ltc2990_show_value, NULL,
+			  LTC2990_IN3);
+static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, ltc2990_show_value, NULL,
+			  LTC2990_IN4);
 
 static struct attribute *ltc2990_attrs[] = {
 	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	&sensor_dev_attr_temp2_input.dev_attr.attr,
+	&sensor_dev_attr_temp3_input.dev_attr.attr,
 	&sensor_dev_attr_curr1_input.dev_attr.attr,
 	&sensor_dev_attr_curr2_input.dev_attr.attr,
 	&sensor_dev_attr_in0_input.dev_attr.attr,
+	&sensor_dev_attr_in1_input.dev_attr.attr,
+	&sensor_dev_attr_in2_input.dev_attr.attr,
+	&sensor_dev_attr_in3_input.dev_attr.attr,
+	&sensor_dev_attr_in4_input.dev_attr.attr,
 	NULL,
 };
-ATTRIBUTE_GROUPS(ltc2990);
+
+static const struct attribute_group ltc2990_group = {
+	.attrs = ltc2990_attrs,
+	.is_visible = ltc2990_attrs_visible,
+};
+__ATTRIBUTE_GROUPS(ltc2990);
 
 static int ltc2990_i2c_probe(struct i2c_client *i2c,
 			     const struct i2c_device_id *id)
 {
 	int ret;
 	struct device *hwmon_dev;
+	struct ltc2990_data *data;
+	struct device_node *of_node = i2c->dev.of_node;
 
 	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
 				     I2C_FUNC_SMBUS_WORD_DATA))
 		return -ENODEV;
 
-	/* Setup continuous mode, current monitor */
+	data = devm_kzalloc(&i2c->dev, sizeof(struct ltc2990_data), GFP_KERNEL);
+	if (unlikely(!data))
+		return -ENOMEM;
+
+	data->i2c = i2c;
+
+	if (of_node) {
+		ret = of_property_read_u32_array(of_node, "lltc,meas-mode",
+						 data->mode, 2);
+		if (ret < 0)
+			return ret;
+
+		if (data->mode[0] & ~LTC2990_MODE0_MASK ||
+		    data->mode[1] & ~LTC2990_MODE1_MASK)
+			return -EINVAL;
+	} else {
+		ret = i2c_smbus_read_byte_data(i2c, LTC2990_CONTROL);
+		if (ret < 0)
+			return ret;
+
+		data->mode[0] = ret >> LTC2990_MODE0_SHIFT & LTC2990_MODE0_MASK;
+		data->mode[1] = ret >> LTC2990_MODE1_SHIFT & LTC2990_MODE1_MASK;
+	}
+
+	/* Setup continuous mode */
 	ret = i2c_smbus_write_byte_data(i2c, LTC2990_CONTROL,
-					LTC2990_CONTROL_MEASURE_ALL |
-					LTC2990_CONTROL_MODE_CURRENT);
+					data->mode[0] << LTC2990_MODE0_SHIFT |
+					data->mode[1] << LTC2990_MODE1_SHIFT);
 	if (ret < 0) {
 		dev_err(&i2c->dev, "Error: Failed to set control mode.\n");
 		return ret;
@@ -124,7 +264,7 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c,
 
 	hwmon_dev = devm_hwmon_device_register_with_groups(&i2c->dev,
 							   i2c->name,
-							   i2c,
+							   data,
 							   ltc2990_groups);
 
 	return PTR_ERR_OR_ZERO(hwmon_dev);
-- 
1.8.3.1

Re: [PATCH v3 3/3] hwmon: ltc2990: support all measurement modes

[Mike Looijmans]

Applied, and tested on my board, so you have my

Tested-By: mike.looijmans-Oq418RWZeHk@public.gmane.org

Probably the maintainers will like to see a patch header mail with a "v3" 
summary for what you've changed ("git send-email --cover-letter" or something 
similar to that)

On 03-07-17 06:29, Tom Levens wrote:
> Updated version of the ltc2990 driver which supports all measurement
> modes (current, voltage, temperature) available in the chip.
> 
> If devicetree is used, the mode must be specified with the property
> "lltc,meas-mode". The format and possible values of the property are
> described in the binding.
> 
> If devicetree is not used, the mode of the chip will not be configured.
> Unless the chip is configured by another source, only the internal
> temperature and supply voltage will be measured.
> 
> Signed-off-by: Tom Levens <tom.levens-vJEk5272eHo@public.gmane.org>
> ---
>   Documentation/hwmon/ltc2990 |  24 ++++--
>   drivers/hwmon/Kconfig       |   7 +-
>   drivers/hwmon/ltc2990.c     | 196 +++++++++++++++++++++++++++++++++++++-------
>   3 files changed, 185 insertions(+), 42 deletions(-)
> 
> diff --git a/Documentation/hwmon/ltc2990 b/Documentation/hwmon/ltc2990
> index c25211e..3ed68f6 100644
> --- a/Documentation/hwmon/ltc2990
> +++ b/Documentation/hwmon/ltc2990
> @@ -8,6 +8,7 @@ Supported chips:
>       Datasheet: http://www.linear.com/product/ltc2990
>   
>   Author: Mike Looijmans <mike.looijmans-Oq418RWZeHk@public.gmane.org>
> +        Tom Levens <tom.levens-vJEk5272eHo@public.gmane.org>
>   
>   
>   Description
> @@ -16,10 +17,8 @@ Description
>   LTC2990 is a Quad I2C Voltage, Current and Temperature Monitor.
>   The chip's inputs can measure 4 voltages, or two inputs together (1+2 and 3+4)
>   can be combined to measure a differential voltage, which is typically used to
> -measure current through a series resistor, or a temperature.
> -
> -This driver currently uses the 2x differential mode only. In order to support
> -other modes, the driver will need to be expanded.
> +measure current through a series resistor, or a temperature with an external
> +diode.
>   
>   
>   Usage Notes
> @@ -32,12 +31,19 @@ devices explicitly.
>   Sysfs attributes
>   ----------------
>   
> +in0_input     Voltage at Vcc pin in millivolt (range 2.5V to 5V)
> +temp1_input   Internal chip temperature in millidegrees Celcius
> +
> +A subset of the following attributes are visible, depending on the measurement
> +mode of the chip.
> +
> +in[1-4]_input Voltage at V[1-4] pin in millivolt
> +temp2_input   External temperature sensor TR1 in millidegrees Celcius
> +temp3_input   External temperature sensor TR2 in millidegrees Celcius
> +curr1_input   Current in mA across V1-V2 assuming a 1mOhm sense resistor
> +curr2_input   Current in mA across V3-V4 assuming a 1mOhm sense resistor
> +
>   The "curr*_input" measurements actually report the voltage drop across the
>   input pins in microvolts. This is equivalent to the current through a 1mOhm
>   sense resistor. Divide the reported value by the actual sense resistor value
>   in mOhm to get the actual value.
> -
> -in0_input     Voltage at Vcc pin in millivolt (range 2.5V to 5V)
> -temp1_input   Internal chip temperature in millidegrees Celcius
> -curr1_input   Current in mA across v1-v2 assuming a 1mOhm sense resistor.
> -curr2_input   Current in mA across v3-v4 assuming a 1mOhm sense resistor.
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 5ef2814..578e5a9 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -709,15 +709,12 @@ config SENSORS_LTC2945
>   	  be called ltc2945.
>   
>   config SENSORS_LTC2990
> -	tristate "Linear Technology LTC2990 (current monitoring mode only)"
> +	tristate "Linear Technology LTC2990"
>   	depends on I2C
>   	help
>   	  If you say yes here you get support for Linear Technology LTC2990
>   	  I2C System Monitor. The LTC2990 supports a combination of voltage,
> -	  current and temperature monitoring, but in addition to the Vcc supply
> -	  voltage and chip temperature, this driver currently only supports
> -	  reading two currents by measuring two differential voltages across
> -	  series resistors.
> +	  current and temperature monitoring.
>   
>   	  This driver can also be built as a module. If so, the module will
>   	  be called ltc2990.
> diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c
> index e320d21..32f3a8d 100644
> --- a/drivers/hwmon/ltc2990.c
> +++ b/drivers/hwmon/ltc2990.c
> @@ -5,10 +5,6 @@
>    * Author: Mike Looijmans <mike.looijmans-Oq418RWZeHk@public.gmane.org>
>    *
>    * License: GPLv2
> - *
> - * This driver assumes the chip is wired as a dual current monitor, and
> - * reports the voltage drop across two series resistors. It also reports
> - * the chip's internal temperature and Vcc power supply voltage.
>    */
>   
>   #include <linux/bitops.h>
> @@ -18,6 +14,7 @@
>   #include <linux/i2c.h>
>   #include <linux/kernel.h>
>   #include <linux/module.h>
> +#include <linux/of.h>
>   
>   #define LTC2990_STATUS	0x00
>   #define LTC2990_CONTROL	0x01
> @@ -29,35 +26,109 @@
>   #define LTC2990_V4_MSB	0x0C
>   #define LTC2990_VCC_MSB	0x0E
>   
> -#define LTC2990_CONTROL_KELVIN		BIT(7)
> -#define LTC2990_CONTROL_SINGLE		BIT(6)
> -#define LTC2990_CONTROL_MEASURE_ALL	(0x3 << 3)
> -#define LTC2990_CONTROL_MODE_CURRENT	0x06
> -#define LTC2990_CONTROL_MODE_VOLTAGE	0x07
> +#define LTC2990_IN0	BIT(0)
> +#define LTC2990_IN1	BIT(1)
> +#define LTC2990_IN2	BIT(2)
> +#define LTC2990_IN3	BIT(3)
> +#define LTC2990_IN4	BIT(4)
> +#define LTC2990_CURR1	BIT(5)
> +#define LTC2990_CURR2	BIT(6)
> +#define LTC2990_TEMP1	BIT(7)
> +#define LTC2990_TEMP2	BIT(8)
> +#define LTC2990_TEMP3	BIT(9)
> +#define LTC2990_NONE	0
> +#define LTC2990_ALL	GENMASK(9, 0)
> +
> +#define LTC2990_MODE0_SHIFT	0
> +#define LTC2990_MODE0_MASK	GENMASK(2, 0)
> +#define LTC2990_MODE1_SHIFT	3
> +#define LTC2990_MODE1_MASK	GENMASK(1, 0)
> +
> +/* Enabled measurements for mode bits 2..0 */
> +static const int ltc2990_attrs_ena_0[] = {
> +	LTC2990_IN1 | LTC2990_IN2 | LTC2990_TEMP3,
> +	LTC2990_CURR1 | LTC2990_TEMP3,
> +	LTC2990_CURR1 | LTC2990_IN3 | LTC2990_IN4,
> +	LTC2990_TEMP2 | LTC2990_IN3 | LTC2990_IN4,
> +	LTC2990_TEMP2 | LTC2990_CURR2,
> +	LTC2990_TEMP2 | LTC2990_TEMP3,
> +	LTC2990_CURR1 | LTC2990_CURR2,
> +	LTC2990_IN1 | LTC2990_IN2 | LTC2990_IN3 | LTC2990_IN4
> +};
> +
> +/* Enabled measurements for mode bits 4..3 */
> +static const int ltc2990_attrs_ena_1[] = {
> +	LTC2990_NONE,
> +	LTC2990_TEMP2 | LTC2990_IN1 | LTC2990_CURR1,
> +	LTC2990_TEMP3 | LTC2990_IN3 | LTC2990_CURR2,
> +	LTC2990_ALL
> +};
> +
> +struct ltc2990_data {
> +	struct i2c_client *i2c;
> +	u32 mode[2];
> +};
>   
>   /* Return the converted value from the given register in uV or mC */
> -static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
> +static int ltc2990_get_value(struct i2c_client *i2c, int index, int *result)
>   {
>   	int val;
> +	u8 reg;
> +
> +	switch (index) {
> +	case LTC2990_IN0:
> +		reg = LTC2990_VCC_MSB;
> +		break;
> +	case LTC2990_IN1:
> +	case LTC2990_CURR1:
> +	case LTC2990_TEMP2:
> +		reg = LTC2990_V1_MSB;
> +		break;
> +	case LTC2990_IN2:
> +		reg = LTC2990_V2_MSB;
> +		break;
> +	case LTC2990_IN3:
> +	case LTC2990_CURR2:
> +	case LTC2990_TEMP3:
> +		reg = LTC2990_V3_MSB;
> +		break;
> +	case LTC2990_IN4:
> +		reg = LTC2990_V4_MSB;
> +		break;
> +	case LTC2990_TEMP1:
> +		reg = LTC2990_TINT_MSB;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
>   
>   	val = i2c_smbus_read_word_swapped(i2c, reg);
>   	if (unlikely(val < 0))
>   		return val;
>   
> -	switch (reg) {
> -	case LTC2990_TINT_MSB:
> -		/* internal temp, 0.0625 degrees/LSB, 13-bit  */
> +	switch (index) {
> +	case LTC2990_TEMP1:
> +	case LTC2990_TEMP2:
> +	case LTC2990_TEMP3:
> +		/* temp, 0.0625 degrees/LSB */
>   		*result = sign_extend32(val, 12) * 1000 / 16;
>   		break;
> -	case LTC2990_V1_MSB:
> -	case LTC2990_V3_MSB:
> -		 /* Vx-Vy, 19.42uV/LSB. Depends on mode. */
> +	case LTC2990_CURR1:
> +	case LTC2990_CURR2:
> +		 /* Vx-Vy, 19.42uV/LSB */
>   		*result = sign_extend32(val, 14) * 1942 / 100;
>   		break;
> -	case LTC2990_VCC_MSB:
> -		/* Vcc, 305.18μV/LSB, 2.5V offset */
> +	case LTC2990_IN0:
> +		/* Vcc, 305.18uV/LSB, 2.5V offset */
>   		*result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500;
>   		break;
> +	case LTC2990_IN1:
> +	case LTC2990_IN2:
> +	case LTC2990_IN3:
> +	case LTC2990_IN4:
> +		/* Vx, 305.18uV/LSB */
> +		*result = sign_extend32(val, 14) * 30518 / (100 * 1000);
> +		break;
>   	default:
>   		return -EINVAL; /* won't happen, keep compiler happy */
>   	}
> @@ -69,48 +140,117 @@ static ssize_t ltc2990_show_value(struct device *dev,
>   				  struct device_attribute *da, char *buf)
>   {
>   	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
> +	struct ltc2990_data *data = dev_get_drvdata(dev);
>   	int value;
>   	int ret;
>   
> -	ret = ltc2990_get_value(dev_get_drvdata(dev), attr->index, &value);
> +	ret = ltc2990_get_value(data->i2c, attr->index, &value);
>   	if (unlikely(ret < 0))
>   		return ret;
>   
>   	return snprintf(buf, PAGE_SIZE, "%d\n", value);
>   }
>   
> +static umode_t ltc2990_attrs_visible(struct kobject *kobj,
> +				     struct attribute *a, int n)
> +{
> +	struct device *dev = container_of(kobj, struct device, kobj);
> +	struct ltc2990_data *data = dev_get_drvdata(dev);
> +	struct device_attribute *da =
> +			container_of(a, struct device_attribute, attr);
> +	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
> +
> +	int attrs_mask = LTC2990_IN0 | LTC2990_TEMP1 |
> +			 ltc2990_attrs_ena_0[data->mode[0]] &
> +			 ltc2990_attrs_ena_1[data->mode[1]];
> +
> +	if (attr->index & attrs_mask)
> +		return a->mode;
> +
> +	return 0;
> +}
> +
>   static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ltc2990_show_value, NULL,
> -			  LTC2990_TINT_MSB);
> +			  LTC2990_TEMP1);
> +static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, ltc2990_show_value, NULL,
> +			  LTC2990_TEMP2);
> +static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, ltc2990_show_value, NULL,
> +			  LTC2990_TEMP3);
>   static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ltc2990_show_value, NULL,
> -			  LTC2990_V1_MSB);
> +			  LTC2990_CURR1);
>   static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO, ltc2990_show_value, NULL,
> -			  LTC2990_V3_MSB);
> +			  LTC2990_CURR2);
>   static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ltc2990_show_value, NULL,
> -			  LTC2990_VCC_MSB);
> +			  LTC2990_IN0);
> +static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ltc2990_show_value, NULL,
> +			  LTC2990_IN1);
> +static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, ltc2990_show_value, NULL,
> +			  LTC2990_IN2);
> +static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, ltc2990_show_value, NULL,
> +			  LTC2990_IN3);
> +static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, ltc2990_show_value, NULL,
> +			  LTC2990_IN4);
>   
>   static struct attribute *ltc2990_attrs[] = {
>   	&sensor_dev_attr_temp1_input.dev_attr.attr,
> +	&sensor_dev_attr_temp2_input.dev_attr.attr,
> +	&sensor_dev_attr_temp3_input.dev_attr.attr,
>   	&sensor_dev_attr_curr1_input.dev_attr.attr,
>   	&sensor_dev_attr_curr2_input.dev_attr.attr,
>   	&sensor_dev_attr_in0_input.dev_attr.attr,
> +	&sensor_dev_attr_in1_input.dev_attr.attr,
> +	&sensor_dev_attr_in2_input.dev_attr.attr,
> +	&sensor_dev_attr_in3_input.dev_attr.attr,
> +	&sensor_dev_attr_in4_input.dev_attr.attr,
>   	NULL,
>   };
> -ATTRIBUTE_GROUPS(ltc2990);
> +
> +static const struct attribute_group ltc2990_group = {
> +	.attrs = ltc2990_attrs,
> +	.is_visible = ltc2990_attrs_visible,
> +};
> +__ATTRIBUTE_GROUPS(ltc2990);
>   
>   static int ltc2990_i2c_probe(struct i2c_client *i2c,
>   			     const struct i2c_device_id *id)
>   {
>   	int ret;
>   	struct device *hwmon_dev;
> +	struct ltc2990_data *data;
> +	struct device_node *of_node = i2c->dev.of_node;
>   
>   	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
>   				     I2C_FUNC_SMBUS_WORD_DATA))
>   		return -ENODEV;
>   
> -	/* Setup continuous mode, current monitor */
> +	data = devm_kzalloc(&i2c->dev, sizeof(struct ltc2990_data), GFP_KERNEL);
> +	if (unlikely(!data))
> +		return -ENOMEM;
> +
> +	data->i2c = i2c;
> +
> +	if (of_node) {
> +		ret = of_property_read_u32_array(of_node, "lltc,meas-mode",
> +						 data->mode, 2);
> +		if (ret < 0)
> +			return ret;
> +
> +		if (data->mode[0] & ~LTC2990_MODE0_MASK ||
> +		    data->mode[1] & ~LTC2990_MODE1_MASK)
> +			return -EINVAL;
> +	} else {
> +		ret = i2c_smbus_read_byte_data(i2c, LTC2990_CONTROL);
> +		if (ret < 0)
> +			return ret;
> +
> +		data->mode[0] = ret >> LTC2990_MODE0_SHIFT & LTC2990_MODE0_MASK;
> +		data->mode[1] = ret >> LTC2990_MODE1_SHIFT & LTC2990_MODE1_MASK;
> +	}
> +
> +	/* Setup continuous mode */
>   	ret = i2c_smbus_write_byte_data(i2c, LTC2990_CONTROL,
> -					LTC2990_CONTROL_MEASURE_ALL |
> -					LTC2990_CONTROL_MODE_CURRENT);
> +					data->mode[0] << LTC2990_MODE0_SHIFT |
> +					data->mode[1] << LTC2990_MODE1_SHIFT);
>   	if (ret < 0) {
>   		dev_err(&i2c->dev, "Error: Failed to set control mode.\n");
>   		return ret;
> @@ -124,7 +264,7 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c,
>   
>   	hwmon_dev = devm_hwmon_device_register_with_groups(&i2c->dev,
>   							   i2c->name,
> -							   i2c,
> +							   data,
>   							   ltc2990_groups);
>   
>   	return PTR_ERR_OR_ZERO(hwmon_dev);
> 



Kind regards,

Mike Looijmans
System Expert

TOPIC Products
Materiaalweg 4, NL-5681 RJ Best
Postbus 440, NL-5680 AK Best
Telefoon: +31 (0) 499 33 69 79
E-mail: mike.looijmans-yhtFebqMsb9it5bFGTN0CAC/G2K4zDHf@public.gmane.org
Website: www.topicproducts.com

Please consider the environment before printing this e-mail



--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v3 3/3] hwmon: ltc2990: support all measurement modes

[Guenter Roeck]

On 07/02/2017 11:29 PM, Mike Looijmans wrote:
> Applied, and tested on my board, so you have my
> 
> Tested-By: mike.looijmans-Oq418RWZeHk@public.gmane.org
> 
> Probably the maintainers will like to see a patch header mail with a "v3" summary for what you've changed ("git send-email --cover-letter" or something similar to that)
> 

... and without it, the patch series tends to end up at the end of my review
list since I'll have to spend time tracking down the changes myself or, per
my choice, start all over and hope I catch all the problems found earlier.

In other words, if people would like their patch series handled with
priority, making life easy for maintainers is a good start.

Guenter

> On 03-07-17 06:29, Tom Levens wrote:
>> Updated version of the ltc2990 driver which supports all measurement
>> modes (current, voltage, temperature) available in the chip.
>>
>> If devicetree is used, the mode must be specified with the property
>> "lltc,meas-mode". The format and possible values of the property are

AFAIK, DT maintainers are not much into abbreviations.

>> described in the binding.
>>
>> If devicetree is not used, the mode of the chip will not be configured.
>> Unless the chip is configured by another source, only the internal
>> temperature and supply voltage will be measured.
>>
>> Signed-off-by: Tom Levens <tom.levens-vJEk5272eHo@public.gmane.org>
>> ---
>>   Documentation/hwmon/ltc2990 |  24 ++++--
>>   drivers/hwmon/Kconfig       |   7 +-
>>   drivers/hwmon/ltc2990.c     | 196 +++++++++++++++++++++++++++++++++++++-------
>>   3 files changed, 185 insertions(+), 42 deletions(-)
>>
>> diff --git a/Documentation/hwmon/ltc2990 b/Documentation/hwmon/ltc2990
>> index c25211e..3ed68f6 100644
>> --- a/Documentation/hwmon/ltc2990
>> +++ b/Documentation/hwmon/ltc2990
>> @@ -8,6 +8,7 @@ Supported chips:
>>       Datasheet: http://www.linear.com/product/ltc2990
>>   Author: Mike Looijmans <mike.looijmans-Oq418RWZeHk@public.gmane.org>
>> +        Tom Levens <tom.levens-vJEk5272eHo@public.gmane.org>
>>   Description
>> @@ -16,10 +17,8 @@ Description
>>   LTC2990 is a Quad I2C Voltage, Current and Temperature Monitor.
>>   The chip's inputs can measure 4 voltages, or two inputs together (1+2 and 3+4)
>>   can be combined to measure a differential voltage, which is typically used to
>> -measure current through a series resistor, or a temperature.
>> -
>> -This driver currently uses the 2x differential mode only. In order to support
>> -other modes, the driver will need to be expanded.
>> +measure current through a series resistor, or a temperature with an external
>> +diode.
>>   Usage Notes
>> @@ -32,12 +31,19 @@ devices explicitly.
>>   Sysfs attributes
>>   ----------------
>> +in0_input     Voltage at Vcc pin in millivolt (range 2.5V to 5V)
>> +temp1_input   Internal chip temperature in millidegrees Celcius
>> +
>> +A subset of the following attributes are visible, depending on the measurement
>> +mode of the chip.
>> +
>> +in[1-4]_input Voltage at V[1-4] pin in millivolt
>> +temp2_input   External temperature sensor TR1 in millidegrees Celcius
>> +temp3_input   External temperature sensor TR2 in millidegrees Celcius
>> +curr1_input   Current in mA across V1-V2 assuming a 1mOhm sense resistor
>> +curr2_input   Current in mA across V3-V4 assuming a 1mOhm sense resistor
>> +
>>   The "curr*_input" measurements actually report the voltage drop across the
>>   input pins in microvolts. This is equivalent to the current through a 1mOhm
>>   sense resistor. Divide the reported value by the actual sense resistor value
>>   in mOhm to get the actual value.
>> -
>> -in0_input     Voltage at Vcc pin in millivolt (range 2.5V to 5V)
>> -temp1_input   Internal chip temperature in millidegrees Celcius
>> -curr1_input   Current in mA across v1-v2 assuming a 1mOhm sense resistor.
>> -curr2_input   Current in mA across v3-v4 assuming a 1mOhm sense resistor.
>> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
>> index 5ef2814..578e5a9 100644
>> --- a/drivers/hwmon/Kconfig
>> +++ b/drivers/hwmon/Kconfig
>> @@ -709,15 +709,12 @@ config SENSORS_LTC2945
>>         be called ltc2945.
>>   config SENSORS_LTC2990
>> -    tristate "Linear Technology LTC2990 (current monitoring mode only)"
>> +    tristate "Linear Technology LTC2990"
>>       depends on I2C
>>       help
>>         If you say yes here you get support for Linear Technology LTC2990
>>         I2C System Monitor. The LTC2990 supports a combination of voltage,
>> -      current and temperature monitoring, but in addition to the Vcc supply
>> -      voltage and chip temperature, this driver currently only supports
>> -      reading two currents by measuring two differential voltages across
>> -      series resistors.
>> +      current and temperature monitoring.
>>         This driver can also be built as a module. If so, the module will
>>         be called ltc2990.
>> diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c
>> index e320d21..32f3a8d 100644
>> --- a/drivers/hwmon/ltc2990.c
>> +++ b/drivers/hwmon/ltc2990.c
>> @@ -5,10 +5,6 @@
>>    * Author: Mike Looijmans <mike.looijmans-Oq418RWZeHk@public.gmane.org>
>>    *
>>    * License: GPLv2
>> - *
>> - * This driver assumes the chip is wired as a dual current monitor, and
>> - * reports the voltage drop across two series resistors. It also reports
>> - * the chip's internal temperature and Vcc power supply voltage.
>>    */
>>   #include <linux/bitops.h>
>> @@ -18,6 +14,7 @@
>>   #include <linux/i2c.h>
>>   #include <linux/kernel.h>
>>   #include <linux/module.h>
>> +#include <linux/of.h>
>>   #define LTC2990_STATUS    0x00
>>   #define LTC2990_CONTROL    0x01
>> @@ -29,35 +26,109 @@
>>   #define LTC2990_V4_MSB    0x0C
>>   #define LTC2990_VCC_MSB    0x0E
>> -#define LTC2990_CONTROL_KELVIN        BIT(7)
>> -#define LTC2990_CONTROL_SINGLE        BIT(6)
>> -#define LTC2990_CONTROL_MEASURE_ALL    (0x3 << 3)
>> -#define LTC2990_CONTROL_MODE_CURRENT    0x06
>> -#define LTC2990_CONTROL_MODE_VOLTAGE    0x07
>> +#define LTC2990_IN0    BIT(0)
>> +#define LTC2990_IN1    BIT(1)
>> +#define LTC2990_IN2    BIT(2)
>> +#define LTC2990_IN3    BIT(3)
>> +#define LTC2990_IN4    BIT(4)
>> +#define LTC2990_CURR1    BIT(5)
>> +#define LTC2990_CURR2    BIT(6)
>> +#define LTC2990_TEMP1    BIT(7)
>> +#define LTC2990_TEMP2    BIT(8)
>> +#define LTC2990_TEMP3    BIT(9)
>> +#define LTC2990_NONE    0
>> +#define LTC2990_ALL    GENMASK(9, 0)
>> +
>> +#define LTC2990_MODE0_SHIFT    0
>> +#define LTC2990_MODE0_MASK    GENMASK(2, 0)
>> +#define LTC2990_MODE1_SHIFT    3
>> +#define LTC2990_MODE1_MASK    GENMASK(1, 0)
>> +
>> +/* Enabled measurements for mode bits 2..0 */
>> +static const int ltc2990_attrs_ena_0[] = {
>> +    LTC2990_IN1 | LTC2990_IN2 | LTC2990_TEMP3,
>> +    LTC2990_CURR1 | LTC2990_TEMP3,
>> +    LTC2990_CURR1 | LTC2990_IN3 | LTC2990_IN4,
>> +    LTC2990_TEMP2 | LTC2990_IN3 | LTC2990_IN4,
>> +    LTC2990_TEMP2 | LTC2990_CURR2,
>> +    LTC2990_TEMP2 | LTC2990_TEMP3,
>> +    LTC2990_CURR1 | LTC2990_CURR2,
>> +    LTC2990_IN1 | LTC2990_IN2 | LTC2990_IN3 | LTC2990_IN4
>> +};
>> +
>> +/* Enabled measurements for mode bits 4..3 */
>> +static const int ltc2990_attrs_ena_1[] = {
>> +    LTC2990_NONE,
>> +    LTC2990_TEMP2 | LTC2990_IN1 | LTC2990_CURR1,
>> +    LTC2990_TEMP3 | LTC2990_IN3 | LTC2990_CURR2,
>> +    LTC2990_ALL
>> +};
>> +
>> +struct ltc2990_data {
>> +    struct i2c_client *i2c;
>> +    u32 mode[2];
>> +};
>>   /* Return the converted value from the given register in uV or mC */
>> -static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
>> +static int ltc2990_get_value(struct i2c_client *i2c, int index, int *result)
>>   {
>>       int val;
>> +    u8 reg;
>> +
>> +    switch (index) {
>> +    case LTC2990_IN0:
>> +        reg = LTC2990_VCC_MSB;
>> +        break;
>> +    case LTC2990_IN1:
>> +    case LTC2990_CURR1:
>> +    case LTC2990_TEMP2:
>> +        reg = LTC2990_V1_MSB;
>> +        break;
>> +    case LTC2990_IN2:
>> +        reg = LTC2990_V2_MSB;
>> +        break;
>> +    case LTC2990_IN3:
>> +    case LTC2990_CURR2:
>> +    case LTC2990_TEMP3:
>> +        reg = LTC2990_V3_MSB;
>> +        break;
>> +    case LTC2990_IN4:
>> +        reg = LTC2990_V4_MSB;
>> +        break;
>> +    case LTC2990_TEMP1:
>> +        reg = LTC2990_TINT_MSB;
>> +        break;
>> +    default:
>> +        return -EINVAL;
>> +    }
>>       val = i2c_smbus_read_word_swapped(i2c, reg);
>>       if (unlikely(val < 0))
>>           return val;
>> -    switch (reg) {
>> -    case LTC2990_TINT_MSB:
>> -        /* internal temp, 0.0625 degrees/LSB, 13-bit  */
>> +    switch (index) {
>> +    case LTC2990_TEMP1:
>> +    case LTC2990_TEMP2:
>> +    case LTC2990_TEMP3:
>> +        /* temp, 0.0625 degrees/LSB */
>>           *result = sign_extend32(val, 12) * 1000 / 16;
>>           break;
>> -    case LTC2990_V1_MSB:
>> -    case LTC2990_V3_MSB:
>> -         /* Vx-Vy, 19.42uV/LSB. Depends on mode. */
>> +    case LTC2990_CURR1:
>> +    case LTC2990_CURR2:
>> +         /* Vx-Vy, 19.42uV/LSB */
>>           *result = sign_extend32(val, 14) * 1942 / 100;
>>           break;
>> -    case LTC2990_VCC_MSB:
>> -        /* Vcc, 305.18μV/LSB, 2.5V offset */
>> +    case LTC2990_IN0:
>> +        /* Vcc, 305.18uV/LSB, 2.5V offset */
>>           *result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500;
>>           break;
>> +    case LTC2990_IN1:
>> +    case LTC2990_IN2:
>> +    case LTC2990_IN3:
>> +    case LTC2990_IN4:
>> +        /* Vx, 305.18uV/LSB */
>> +        *result = sign_extend32(val, 14) * 30518 / (100 * 1000);
>> +        break;
>>       default:
>>           return -EINVAL; /* won't happen, keep compiler happy */
>>       }
>> @@ -69,48 +140,117 @@ static ssize_t ltc2990_show_value(struct device *dev,
>>                     struct device_attribute *da, char *buf)
>>   {
>>       struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
>> +    struct ltc2990_data *data = dev_get_drvdata(dev);
>>       int value;
>>       int ret;
>> -    ret = ltc2990_get_value(dev_get_drvdata(dev), attr->index, &value);
>> +    ret = ltc2990_get_value(data->i2c, attr->index, &value);
>>       if (unlikely(ret < 0))
>>           return ret;
>>       return snprintf(buf, PAGE_SIZE, "%d\n", value);
>>   }
>> +static umode_t ltc2990_attrs_visible(struct kobject *kobj,
>> +                     struct attribute *a, int n)
>> +{
>> +    struct device *dev = container_of(kobj, struct device, kobj);
>> +    struct ltc2990_data *data = dev_get_drvdata(dev);
>> +    struct device_attribute *da =
>> +            container_of(a, struct device_attribute, attr);
>> +    struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
>> +
>> +    int attrs_mask = LTC2990_IN0 | LTC2990_TEMP1 |
>> +             ltc2990_attrs_ena_0[data->mode[0]] &
>> +             ltc2990_attrs_ena_1[data->mode[1]];
>> +
>> +    if (attr->index & attrs_mask)
>> +        return a->mode;
>> +
>> +    return 0;
>> +}
>> +
>>   static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ltc2990_show_value, NULL,
>> -              LTC2990_TINT_MSB);
>> +              LTC2990_TEMP1);
>> +static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, ltc2990_show_value, NULL,
>> +              LTC2990_TEMP2);
>> +static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, ltc2990_show_value, NULL,
>> +              LTC2990_TEMP3);
>>   static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ltc2990_show_value, NULL,
>> -              LTC2990_V1_MSB);
>> +              LTC2990_CURR1);
>>   static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO, ltc2990_show_value, NULL,
>> -              LTC2990_V3_MSB);
>> +              LTC2990_CURR2);
>>   static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ltc2990_show_value, NULL,
>> -              LTC2990_VCC_MSB);
>> +              LTC2990_IN0);
>> +static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ltc2990_show_value, NULL,
>> +              LTC2990_IN1);
>> +static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, ltc2990_show_value, NULL,
>> +              LTC2990_IN2);
>> +static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, ltc2990_show_value, NULL,
>> +              LTC2990_IN3);
>> +static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, ltc2990_show_value, NULL,
>> +              LTC2990_IN4);
>>   static struct attribute *ltc2990_attrs[] = {
>>       &sensor_dev_attr_temp1_input.dev_attr.attr,
>> +    &sensor_dev_attr_temp2_input.dev_attr.attr,
>> +    &sensor_dev_attr_temp3_input.dev_attr.attr,
>>       &sensor_dev_attr_curr1_input.dev_attr.attr,
>>       &sensor_dev_attr_curr2_input.dev_attr.attr,
>>       &sensor_dev_attr_in0_input.dev_attr.attr,
>> +    &sensor_dev_attr_in1_input.dev_attr.attr,
>> +    &sensor_dev_attr_in2_input.dev_attr.attr,
>> +    &sensor_dev_attr_in3_input.dev_attr.attr,
>> +    &sensor_dev_attr_in4_input.dev_attr.attr,
>>       NULL,
>>   };
>> -ATTRIBUTE_GROUPS(ltc2990);
>> +
>> +static const struct attribute_group ltc2990_group = {
>> +    .attrs = ltc2990_attrs,
>> +    .is_visible = ltc2990_attrs_visible,
>> +};
>> +__ATTRIBUTE_GROUPS(ltc2990);
>>   static int ltc2990_i2c_probe(struct i2c_client *i2c,
>>                    const struct i2c_device_id *id)
>>   {
>>       int ret;
>>       struct device *hwmon_dev;
>> +    struct ltc2990_data *data;
>> +    struct device_node *of_node = i2c->dev.of_node;
>>       if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
>>                        I2C_FUNC_SMBUS_WORD_DATA))
>>           return -ENODEV;
>> -    /* Setup continuous mode, current monitor */
>> +    data = devm_kzalloc(&i2c->dev, sizeof(struct ltc2990_data), GFP_KERNEL);
>> +    if (unlikely(!data))
>> +        return -ENOMEM;
>> +
>> +    data->i2c = i2c;
>> +
>> +    if (of_node) {
>> +        ret = of_property_read_u32_array(of_node, "lltc,meas-mode",
>> +                         data->mode, 2);
>> +        if (ret < 0)
>> +            return ret;
>> +
>> +        if (data->mode[0] & ~LTC2990_MODE0_MASK ||
>> +            data->mode[1] & ~LTC2990_MODE1_MASK)
>> +            return -EINVAL;
>> +    } else {
>> +        ret = i2c_smbus_read_byte_data(i2c, LTC2990_CONTROL);
>> +        if (ret < 0)
>> +            return ret;
>> +
>> +        data->mode[0] = ret >> LTC2990_MODE0_SHIFT & LTC2990_MODE0_MASK;
>> +        data->mode[1] = ret >> LTC2990_MODE1_SHIFT & LTC2990_MODE1_MASK;
>> +    }
>> +
>> +    /* Setup continuous mode */
>>       ret = i2c_smbus_write_byte_data(i2c, LTC2990_CONTROL,
>> -                    LTC2990_CONTROL_MEASURE_ALL |
>> -                    LTC2990_CONTROL_MODE_CURRENT);
>> +                    data->mode[0] << LTC2990_MODE0_SHIFT |
>> +                    data->mode[1] << LTC2990_MODE1_SHIFT);
>>       if (ret < 0) {
>>           dev_err(&i2c->dev, "Error: Failed to set control mode.\n");
>>           return ret;
>> @@ -124,7 +264,7 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c,
>>       hwmon_dev = devm_hwmon_device_register_with_groups(&i2c->dev,
>>                                  i2c->name,
>> -                               i2c,
>> +                               data,
>>                                  ltc2990_groups);
>>       return PTR_ERR_OR_ZERO(hwmon_dev);
>>
> 
> 
> 
> Kind regards,
> 
> Mike Looijmans
> System Expert
> 
> TOPIC Products
> Materiaalweg 4, NL-5681 RJ Best
> Postbus 440, NL-5680 AK Best
> Telefoon: +31 (0) 499 33 69 79
> E-mail: mike.looijmans-yhtFebqMsb9it5bFGTN0CAC/G2K4zDHf@public.gmane.org
> Website: www.topicproducts.com
> 
> Please consider the environment before printing this e-mail
> 
> 
> 
> 

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v3 3/3] hwmon: ltc2990: support all measurement modes

[Tom Levens]

[-- Attachment #1: Type: text/plain, Size: 17459 bytes --]



On Mon, 3 Jul 2017, Guenter Roeck wrote:

> On 07/02/2017 11:29 PM, Mike Looijmans wrote:
>>  Applied, and tested on my board, so you have my
>>
>>  Tested-By: mike.looijmans@topic.nl
>>
>>  Probably the maintainers will like to see a patch header mail with a "v3"
>>  summary for what you've changed ("git send-email --cover-letter" or
>>  something similar to that)
>> 
>
> ... and without it, the patch series tends to end up at the end of my review
> list since I'll have to spend time tracking down the changes myself or, per
> my choice, start all over and hope I catch all the problems found earlier.
>
> In other words, if people would like their patch series handled with
> priority, making life easy for maintainers is a good start.

Apologies, it seems the change summary got lost when sending the patches. 
Here it is:

Changes since v2:
  * If a devicetree node does not exist, do not initialise the chip. In
    this case it is assumed that the initialisation has been done by
    another source.
  * Allow configuration of both of the "mode" fields in the control
    register.
  * Rename the devicetree property lltc->mode to lltc->meas-mode.
  * Specifying the mode in the devicetree node is now mandatory.
  * Small documentation updates.
  * Revert some unnecessary change of types.

> Guenter
>
>>  On 03-07-17 06:29, Tom Levens wrote:
>> >  Updated version of the ltc2990 driver which supports all measurement
>> >  modes (current, voltage, temperature) available in the chip.
>> > 
>> >  If devicetree is used, the mode must be specified with the property
>> >  "lltc,meas-mode". The format and possible values of the property are
>
> AFAIK, DT maintainers are not much into abbreviations.

As far as I recall, this change was the suggestion of Rob as "mode" was 
too vague.

>> >  described in the binding.
>> > 
>> >  If devicetree is not used, the mode of the chip will not be configured.
>> >  Unless the chip is configured by another source, only the internal
>> >  temperature and supply voltage will be measured.
>> > 
>> >  Signed-off-by: Tom Levens <tom.levens@cern.ch>
>> >  ---
>> >    Documentation/hwmon/ltc2990 |  24 ++++--
>> >    drivers/hwmon/Kconfig       |   7 +-
>> >    drivers/hwmon/ltc2990.c     | 196 
>> >    +++++++++++++++++++++++++++++++++++++-------
>> >    3 files changed, 185 insertions(+), 42 deletions(-)
>> > 
>> >  diff --git a/Documentation/hwmon/ltc2990 b/Documentation/hwmon/ltc2990
>> >  index c25211e..3ed68f6 100644
>> >  --- a/Documentation/hwmon/ltc2990
>> >  +++ b/Documentation/hwmon/ltc2990
>> >  @@ -8,6 +8,7 @@ Supported chips:
>> >        Datasheet: http://www.linear.com/product/ltc2990
>> >    Author: Mike Looijmans <mike.looijmans@topic.nl>
>> >  +        Tom Levens <tom.levens@cern.ch>
>> >    Description
>> >  @@ -16,10 +17,8 @@ Description
>> >    LTC2990 is a Quad I2C Voltage, Current and Temperature Monitor.
>> >    The chip's inputs can measure 4 voltages, or two inputs together (1+2 
>> >    and 3+4)
>> >    can be combined to measure a differential voltage, which is typically 
>> >    used to
>> >  -measure current through a series resistor, or a temperature.
>> >  -
>> >  -This driver currently uses the 2x differential mode only. In order to 
>> >  support
>> >  -other modes, the driver will need to be expanded.
>> >  +measure current through a series resistor, or a temperature with an 
>> >  external
>> >  +diode.
>> >    Usage Notes
>> >  @@ -32,12 +31,19 @@ devices explicitly.
>> >    Sysfs attributes
>> >    ----------------
>> >  +in0_input     Voltage at Vcc pin in millivolt (range 2.5V to 5V)
>> >  +temp1_input   Internal chip temperature in millidegrees Celcius
>> >  +
>> >  +A subset of the following attributes are visible, depending on the 
>> >  measurement
>> >  +mode of the chip.
>> >  +
>> >  +in[1-4]_input Voltage at V[1-4] pin in millivolt
>> >  +temp2_input   External temperature sensor TR1 in millidegrees Celcius
>> >  +temp3_input   External temperature sensor TR2 in millidegrees Celcius
>> >  +curr1_input   Current in mA across V1-V2 assuming a 1mOhm sense 
>> >  resistor
>> >  +curr2_input   Current in mA across V3-V4 assuming a 1mOhm sense 
>> >  resistor
>> >  +
>> >    The "curr*_input" measurements actually report the voltage drop across 
>> >    the
>> >    input pins in microvolts. This is equivalent to the current through a 
>> >    1mOhm
>> >    sense resistor. Divide the reported value by the actual sense resistor 
>> >    value
>> >    in mOhm to get the actual value.
>> >  -
>> >  -in0_input     Voltage at Vcc pin in millivolt (range 2.5V to 5V)
>> >  -temp1_input   Internal chip temperature in millidegrees Celcius
>> >  -curr1_input   Current in mA across v1-v2 assuming a 1mOhm sense 
>> >  resistor.
>> >  -curr2_input   Current in mA across v3-v4 assuming a 1mOhm sense 
>> >  resistor.
>> >  diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
>> >  index 5ef2814..578e5a9 100644
>> >  --- a/drivers/hwmon/Kconfig
>> >  +++ b/drivers/hwmon/Kconfig
>> >  @@ -709,15 +709,12 @@ config SENSORS_LTC2945
>> >          be called ltc2945.
>> >    config SENSORS_LTC2990
>> >  -    tristate "Linear Technology LTC2990 (current monitoring mode only)"
>> >  +    tristate "Linear Technology LTC2990"
>> >        depends on I2C
>> >        help
>> >          If you say yes here you get support for Linear Technology 
>> >          LTC2990
>> >          I2C System Monitor. The LTC2990 supports a combination of 
>> >          voltage,
>> >  -      current and temperature monitoring, but in addition to the Vcc 
>> >  supply
>> >  -      voltage and chip temperature, this driver currently only supports
>> >  -      reading two currents by measuring two differential voltages 
>> >  across
>> >  -      series resistors.
>> >  +      current and temperature monitoring.
>> >          This driver can also be built as a module. If so, the module 
>> >          will
>> >          be called ltc2990.
>> >  diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c
>> >  index e320d21..32f3a8d 100644
>> >  --- a/drivers/hwmon/ltc2990.c
>> >  +++ b/drivers/hwmon/ltc2990.c
>> >  @@ -5,10 +5,6 @@
>> >     * Author: Mike Looijmans <mike.looijmans@topic.nl>
>> >     *
>> >     * License: GPLv2
>> >  - *
>> >  - * This driver assumes the chip is wired as a dual current monitor, and
>> >  - * reports the voltage drop across two series resistors. It also 
>> >  reports
>> >  - * the chip's internal temperature and Vcc power supply voltage.
>> >    */
>> >    #include <linux/bitops.h>
>> >  @@ -18,6 +14,7 @@
>> >    #include <linux/i2c.h>
>> >    #include <linux/kernel.h>
>> >    #include <linux/module.h>
>> >  +#include <linux/of.h>
>> >    #define LTC2990_STATUS    0x00
>> >    #define LTC2990_CONTROL    0x01
>> >  @@ -29,35 +26,109 @@
>> >    #define LTC2990_V4_MSB    0x0C
>> >    #define LTC2990_VCC_MSB    0x0E
>> >  -#define LTC2990_CONTROL_KELVIN        BIT(7)
>> >  -#define LTC2990_CONTROL_SINGLE        BIT(6)
>> >  -#define LTC2990_CONTROL_MEASURE_ALL    (0x3 << 3)
>> >  -#define LTC2990_CONTROL_MODE_CURRENT    0x06
>> >  -#define LTC2990_CONTROL_MODE_VOLTAGE    0x07
>> >  +#define LTC2990_IN0    BIT(0)
>> >  +#define LTC2990_IN1    BIT(1)
>> >  +#define LTC2990_IN2    BIT(2)
>> >  +#define LTC2990_IN3    BIT(3)
>> >  +#define LTC2990_IN4    BIT(4)
>> >  +#define LTC2990_CURR1    BIT(5)
>> >  +#define LTC2990_CURR2    BIT(6)
>> >  +#define LTC2990_TEMP1    BIT(7)
>> >  +#define LTC2990_TEMP2    BIT(8)
>> >  +#define LTC2990_TEMP3    BIT(9)
>> >  +#define LTC2990_NONE    0
>> >  +#define LTC2990_ALL    GENMASK(9, 0)
>> >  +
>> >  +#define LTC2990_MODE0_SHIFT    0
>> >  +#define LTC2990_MODE0_MASK    GENMASK(2, 0)
>> >  +#define LTC2990_MODE1_SHIFT    3
>> >  +#define LTC2990_MODE1_MASK    GENMASK(1, 0)
>> >  +
>> >  +/* Enabled measurements for mode bits 2..0 */
>> >  +static const int ltc2990_attrs_ena_0[] = {
>> >  +    LTC2990_IN1 | LTC2990_IN2 | LTC2990_TEMP3,
>> >  +    LTC2990_CURR1 | LTC2990_TEMP3,
>> >  +    LTC2990_CURR1 | LTC2990_IN3 | LTC2990_IN4,
>> >  +    LTC2990_TEMP2 | LTC2990_IN3 | LTC2990_IN4,
>> >  +    LTC2990_TEMP2 | LTC2990_CURR2,
>> >  +    LTC2990_TEMP2 | LTC2990_TEMP3,
>> >  +    LTC2990_CURR1 | LTC2990_CURR2,
>> >  +    LTC2990_IN1 | LTC2990_IN2 | LTC2990_IN3 | LTC2990_IN4
>> >  +};
>> >  +
>> >  +/* Enabled measurements for mode bits 4..3 */
>> >  +static const int ltc2990_attrs_ena_1[] = {
>> >  +    LTC2990_NONE,
>> >  +    LTC2990_TEMP2 | LTC2990_IN1 | LTC2990_CURR1,
>> >  +    LTC2990_TEMP3 | LTC2990_IN3 | LTC2990_CURR2,
>> >  +    LTC2990_ALL
>> >  +};
>> >  +
>> >  +struct ltc2990_data {
>> >  +    struct i2c_client *i2c;
>> >  +    u32 mode[2];
>> >  +};
>> >    /* Return the converted value from the given register in uV or mC */
>> >  -static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int 
>> >  *result)
>> >  +static int ltc2990_get_value(struct i2c_client *i2c, int index, int 
>> >  *result)
>> >    {
>> >        int val;
>> >  +    u8 reg;
>> >  +
>> >  +    switch (index) {
>> >  +    case LTC2990_IN0:
>> >  +        reg = LTC2990_VCC_MSB;
>> >  +        break;
>> >  +    case LTC2990_IN1:
>> >  +    case LTC2990_CURR1:
>> >  +    case LTC2990_TEMP2:
>> >  +        reg = LTC2990_V1_MSB;
>> >  +        break;
>> >  +    case LTC2990_IN2:
>> >  +        reg = LTC2990_V2_MSB;
>> >  +        break;
>> >  +    case LTC2990_IN3:
>> >  +    case LTC2990_CURR2:
>> >  +    case LTC2990_TEMP3:
>> >  +        reg = LTC2990_V3_MSB;
>> >  +        break;
>> >  +    case LTC2990_IN4:
>> >  +        reg = LTC2990_V4_MSB;
>> >  +        break;
>> >  +    case LTC2990_TEMP1:
>> >  +        reg = LTC2990_TINT_MSB;
>> >  +        break;
>> >  +    default:
>> >  +        return -EINVAL;
>> >  +    }
>> >        val = i2c_smbus_read_word_swapped(i2c, reg);
>> >        if (unlikely(val < 0))
>> >            return val;
>> >  -    switch (reg) {
>> >  -    case LTC2990_TINT_MSB:
>> >  -        /* internal temp, 0.0625 degrees/LSB, 13-bit  */
>> >  +    switch (index) {
>> >  +    case LTC2990_TEMP1:
>> >  +    case LTC2990_TEMP2:
>> >  +    case LTC2990_TEMP3:
>> >  +        /* temp, 0.0625 degrees/LSB */
>> >            *result = sign_extend32(val, 12) * 1000 / 16;
>> >            break;
>> >  -    case LTC2990_V1_MSB:
>> >  -    case LTC2990_V3_MSB:
>> >  -         /* Vx-Vy, 19.42uV/LSB. Depends on mode. */
>> >  +    case LTC2990_CURR1:
>> >  +    case LTC2990_CURR2:
>> >  +         /* Vx-Vy, 19.42uV/LSB */
>> >            *result = sign_extend32(val, 14) * 1942 / 100;
>> >            break;
>> >  -    case LTC2990_VCC_MSB:
>> >  -        /* Vcc, 305.18μV/LSB, 2.5V offset */
>> >  +    case LTC2990_IN0:
>> >  +        /* Vcc, 305.18uV/LSB, 2.5V offset */
>> >            *result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 
>> >            2500;
>> >            break;
>> >  +    case LTC2990_IN1:
>> >  +    case LTC2990_IN2:
>> >  +    case LTC2990_IN3:
>> >  +    case LTC2990_IN4:
>> >  +        /* Vx, 305.18uV/LSB */
>> >  +        *result = sign_extend32(val, 14) * 30518 / (100 * 1000);
>> >  +        break;
>> >        default:
>> >            return -EINVAL; /* won't happen, keep compiler happy */
>> >        }
>> >  @@ -69,48 +140,117 @@ static ssize_t ltc2990_show_value(struct device 
>> >  *dev,
>> >                      struct device_attribute *da, char *buf)
>> >    {
>> >        struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
>> >  +    struct ltc2990_data *data = dev_get_drvdata(dev);
>> >        int value;
>> >        int ret;
>> >  -    ret = ltc2990_get_value(dev_get_drvdata(dev), attr->index, &value);
>> >  +    ret = ltc2990_get_value(data->i2c, attr->index, &value);
>> >        if (unlikely(ret < 0))
>> >            return ret;
>> >        return snprintf(buf, PAGE_SIZE, "%d\n", value);
>> >    }
>> >  +static umode_t ltc2990_attrs_visible(struct kobject *kobj,
>> >  +                     struct attribute *a, int n)
>> >  +{
>> >  +    struct device *dev = container_of(kobj, struct device, kobj);
>> >  +    struct ltc2990_data *data = dev_get_drvdata(dev);
>> >  +    struct device_attribute *da =
>> >  +            container_of(a, struct device_attribute, attr);
>> >  +    struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
>> >  +
>> >  +    int attrs_mask = LTC2990_IN0 | LTC2990_TEMP1 |
>> >  +             ltc2990_attrs_ena_0[data->mode[0]] &
>> >  +             ltc2990_attrs_ena_1[data->mode[1]];
>> >  +
>> >  +    if (attr->index & attrs_mask)
>> >  +        return a->mode;
>> >  +
>> >  +    return 0;
>> >  +}
>> >  +
>> >    static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ltc2990_show_value, 
>> >  NULL,
>> >  -              LTC2990_TINT_MSB);
>> >  +              LTC2990_TEMP1);
>> >  +static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, ltc2990_show_value, 
>> >  NULL,
>> >  +              LTC2990_TEMP2);
>> >  +static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, ltc2990_show_value, 
>> >  NULL,
>> >  +              LTC2990_TEMP3);
>> >    static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ltc2990_show_value, 
>> >  NULL,
>> >  -              LTC2990_V1_MSB);
>> >  +              LTC2990_CURR1);
>> >    static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO, ltc2990_show_value, 
>> >  NULL,
>> >  -              LTC2990_V3_MSB);
>> >  +              LTC2990_CURR2);
>> >    static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ltc2990_show_value, 
>> >  NULL,
>> >  -              LTC2990_VCC_MSB);
>> >  +              LTC2990_IN0);
>> >  +static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ltc2990_show_value, NULL,
>> >  +              LTC2990_IN1);
>> >  +static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, ltc2990_show_value, NULL,
>> >  +              LTC2990_IN2);
>> >  +static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, ltc2990_show_value, NULL,
>> >  +              LTC2990_IN3);
>> >  +static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, ltc2990_show_value, NULL,
>> >  +              LTC2990_IN4);
>> >    static struct attribute *ltc2990_attrs[] = {
>> > & sensor_dev_attr_temp1_input.dev_attr.attr,
>> >  +    &sensor_dev_attr_temp2_input.dev_attr.attr,
>> >  +    &sensor_dev_attr_temp3_input.dev_attr.attr,
>> > & sensor_dev_attr_curr1_input.dev_attr.attr,
>> > & sensor_dev_attr_curr2_input.dev_attr.attr,
>> > & sensor_dev_attr_in0_input.dev_attr.attr,
>> >  +    &sensor_dev_attr_in1_input.dev_attr.attr,
>> >  +    &sensor_dev_attr_in2_input.dev_attr.attr,
>> >  +    &sensor_dev_attr_in3_input.dev_attr.attr,
>> >  +    &sensor_dev_attr_in4_input.dev_attr.attr,
>> >        NULL,
>> >    };
>> >  -ATTRIBUTE_GROUPS(ltc2990);
>> >  +
>> >  +static const struct attribute_group ltc2990_group = {
>> >  +    .attrs = ltc2990_attrs,
>> >  +    .is_visible = ltc2990_attrs_visible,
>> >  +};
>> >  +__ATTRIBUTE_GROUPS(ltc2990);
>> >    static int ltc2990_i2c_probe(struct i2c_client *i2c,
>> >                     const struct i2c_device_id *id)
>> >    {
>> >        int ret;
>> >        struct device *hwmon_dev;
>> >  +    struct ltc2990_data *data;
>> >  +    struct device_node *of_node = i2c->dev.of_node;
>> >        if (!i2c_check_functionality(i2c->adapter, 
>> >        I2C_FUNC_SMBUS_BYTE_DATA |
>> >                         I2C_FUNC_SMBUS_WORD_DATA))
>> >            return -ENODEV;
>> >  -    /* Setup continuous mode, current monitor */
>> >  +    data = devm_kzalloc(&i2c->dev, sizeof(struct ltc2990_data), 
>> >  GFP_KERNEL);
>> >  +    if (unlikely(!data))
>> >  +        return -ENOMEM;
>> >  +
>> >  +    data->i2c = i2c;
>> >  +
>> >  +    if (of_node) {
>> >  +        ret = of_property_read_u32_array(of_node, "lltc,meas-mode",
>> >  +                         data->mode, 2);
>> >  +        if (ret < 0)
>> >  +            return ret;
>> >  +
>> >  +        if (data->mode[0] & ~LTC2990_MODE0_MASK ||
>> >  +            data->mode[1] & ~LTC2990_MODE1_MASK)
>> >  +            return -EINVAL;
>> >  +    } else {
>> >  +        ret = i2c_smbus_read_byte_data(i2c, LTC2990_CONTROL);
>> >  +        if (ret < 0)
>> >  +            return ret;
>> >  +
>> >  +        data->mode[0] = ret >> LTC2990_MODE0_SHIFT & 
>> >  LTC2990_MODE0_MASK;
>> >  +        data->mode[1] = ret >> LTC2990_MODE1_SHIFT & 
>> >  LTC2990_MODE1_MASK;
>> >  +    }
>> >  +
>> >  +    /* Setup continuous mode */
>> >        ret = i2c_smbus_write_byte_data(i2c, LTC2990_CONTROL,
>> >  -                    LTC2990_CONTROL_MEASURE_ALL |
>> >  -                    LTC2990_CONTROL_MODE_CURRENT);
>> >  +                    data->mode[0] << LTC2990_MODE0_SHIFT |
>> >  +                    data->mode[1] << LTC2990_MODE1_SHIFT);
>> >        if (ret < 0) {
>> >            dev_err(&i2c->dev, "Error: Failed to set control mode.\n");
>> >            return ret;
>> >  @@ -124,7 +264,7 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c,
>> >        hwmon_dev = devm_hwmon_device_register_with_groups(&i2c->dev,
>> >                                   i2c->name,
>> >  -                               i2c,
>> >  +                               data,
>> >                                   ltc2990_groups);
>> >        return PTR_ERR_OR_ZERO(hwmon_dev);
>> >
>>
>>
>>
>>  Kind regards,
>>
>>  Mike Looijmans
>>  System Expert
>>
>>  TOPIC Products
>>  Materiaalweg 4, NL-5681 RJ Best
>>  Postbus 440, NL-5680 AK Best
>>  Telefoon: +31 (0) 499 33 69 79
>>  E-mail: mike.looijmans@topicproducts.com
>>  Website: www.topicproducts.com
>>
>>  Please consider the environment before printing this e-mail
>>
>>
>>
>> 
>
>

Re: [PATCH v3 3/3] hwmon: ltc2990: support all measurement modes

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 2030 bytes --]

Hi Tom,

[auto build test WARNING on hwmon/hwmon-next]
[also build test WARNING on v4.12 next-20170704]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Tom-Levens/hwmon-ltc2990-refactor-value-conversion/20170705-050920
base:   https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git hwmon-next
config: x86_64-randconfig-x010-201727 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All warnings (new ones prefixed by >>):

   drivers/hwmon/ltc2990.c: In function 'ltc2990_attrs_visible':
>> drivers/hwmon/ltc2990.c:164:40: warning: suggest parentheses around arithmetic in operand of '|' [-Wparentheses]
        ltc2990_attrs_ena_0[data->mode[0]] &
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
        ltc2990_attrs_ena_1[data->mode[1]];
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  

vim +164 drivers/hwmon/ltc2990.c

   148		if (unlikely(ret < 0))
   149			return ret;
   150	
   151		return snprintf(buf, PAGE_SIZE, "%d\n", value);
   152	}
   153	
   154	static umode_t ltc2990_attrs_visible(struct kobject *kobj,
   155					     struct attribute *a, int n)
   156	{
   157		struct device *dev = container_of(kobj, struct device, kobj);
   158		struct ltc2990_data *data = dev_get_drvdata(dev);
   159		struct device_attribute *da =
   160				container_of(a, struct device_attribute, attr);
   161		struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
   162	
   163		int attrs_mask = LTC2990_IN0 | LTC2990_TEMP1 |
 > 164				 ltc2990_attrs_ena_0[data->mode[0]] &
   165				 ltc2990_attrs_ena_1[data->mode[1]];
   166	
   167		if (attr->index & attrs_mask)
   168			return a->mode;
   169	
   170		return 0;
   171	}
   172	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 27950 bytes --]

Re: [v3,1/3] hwmon: ltc2990: refactor value conversion

[Guenter Roeck]

On Mon, Jul 03, 2017 at 06:28:58AM +0200, Tom Levens wrote:
> Conversion from raw values to signed integers has been refactored using
> bitops.h. This also fixes a bug where negative temperatures were
> converted incorrectly.
> 

Documentation/process/submitting-patches.rst, chapter 2: "Solve only one
problem per patch.".

I can understand the urge to merge two sets of changes here. However,
that creates a problem for me: The fix should be applied to stable kernels,
but not the refactoring.

Please split the patch in two, one for the bug fix and one for the
refactoring.

Thanks,
Guenter

> Signed-off-by: Tom Levens <tom.levens@cern.ch>
> ---
>  drivers/hwmon/ltc2990.c | 18 ++++--------------
>  1 file changed, 4 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c
> index 8f8fe05..e320d21 100644
> --- a/drivers/hwmon/ltc2990.c
> +++ b/drivers/hwmon/ltc2990.c
> @@ -11,6 +11,7 @@
>   * the chip's internal temperature and Vcc power supply voltage.
>   */
>  
> +#include <linux/bitops.h>
>  #include <linux/err.h>
>  #include <linux/hwmon.h>
>  #include <linux/hwmon-sysfs.h>
> @@ -34,15 +35,6 @@
>  #define LTC2990_CONTROL_MODE_CURRENT	0x06
>  #define LTC2990_CONTROL_MODE_VOLTAGE	0x07
>  
> -/* convert raw register value to sign-extended integer in 16-bit range */
> -static int ltc2990_voltage_to_int(int raw)
> -{
> -	if (raw & BIT(14))
> -		return -(0x4000 - (raw & 0x3FFF)) << 2;
> -	else
> -		return (raw & 0x3FFF) << 2;
> -}
> -
>  /* Return the converted value from the given register in uV or mC */
>  static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
>  {
> @@ -55,18 +47,16 @@ static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
>  	switch (reg) {
>  	case LTC2990_TINT_MSB:
>  		/* internal temp, 0.0625 degrees/LSB, 13-bit  */
> -		val = (val & 0x1FFF) << 3;
> -		*result = (val * 1000) >> 7;
> +		*result = sign_extend32(val, 12) * 1000 / 16;
>  		break;
>  	case LTC2990_V1_MSB:
>  	case LTC2990_V3_MSB:
>  		 /* Vx-Vy, 19.42uV/LSB. Depends on mode. */
> -		*result = ltc2990_voltage_to_int(val) * 1942 / (4 * 100);
> +		*result = sign_extend32(val, 14) * 1942 / 100;
>  		break;
>  	case LTC2990_VCC_MSB:
>  		/* Vcc, 305.18μV/LSB, 2.5V offset */
> -		*result = (ltc2990_voltage_to_int(val) * 30518 /
> -			   (4 * 100 * 1000)) + 2500;
> +		*result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500;
>  		break;
>  	default:
>  		return -EINVAL; /* won't happen, keep compiler happy */

Re: [v3,1/3] hwmon: ltc2990: refactor value conversion

[Tom Levens]

[-- Attachment #1: Type: text/plain, Size: 2923 bytes --]



On Sat, 8 Jul 2017, Guenter Roeck wrote:

> On Mon, Jul 03, 2017 at 06:28:58AM +0200, Tom Levens wrote:
>> Conversion from raw values to signed integers has been refactored using
>> bitops.h. This also fixes a bug where negative temperatures were
>> converted incorrectly.
>>
>
> Documentation/process/submitting-patches.rst, chapter 2: "Solve only one
> problem per patch.".
>
> I can understand the urge to merge two sets of changes here. However,
> that creates a problem for me: The fix should be applied to stable kernels,
> but not the refactoring.
>
> Please split the patch in two, one for the bug fix and one for the
> refactoring.

In reality the refactoring *is* the fix for this bug. I am not sure how to 
to fix it simply without using the bitops macro. Of course, I could fix 
only the temperature conversion in one patch and refactor the other two in 
a separate one if you prefer?

Cheers,

> Thanks,
> Guenter
>
>> Signed-off-by: Tom Levens <tom.levens-vJEk5272eHo@public.gmane.org>
>> ---
>>  drivers/hwmon/ltc2990.c | 18 ++++--------------
>>  1 file changed, 4 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c
>> index 8f8fe05..e320d21 100644
>> --- a/drivers/hwmon/ltc2990.c
>> +++ b/drivers/hwmon/ltc2990.c
>> @@ -11,6 +11,7 @@
>>   * the chip's internal temperature and Vcc power supply voltage.
>>   */
>>
>> +#include <linux/bitops.h>
>>  #include <linux/err.h>
>>  #include <linux/hwmon.h>
>>  #include <linux/hwmon-sysfs.h>
>> @@ -34,15 +35,6 @@
>>  #define LTC2990_CONTROL_MODE_CURRENT	0x06
>>  #define LTC2990_CONTROL_MODE_VOLTAGE	0x07
>>
>> -/* convert raw register value to sign-extended integer in 16-bit range */
>> -static int ltc2990_voltage_to_int(int raw)
>> -{
>> -	if (raw & BIT(14))
>> -		return -(0x4000 - (raw & 0x3FFF)) << 2;
>> -	else
>> -		return (raw & 0x3FFF) << 2;
>> -}
>> -
>>  /* Return the converted value from the given register in uV or mC */
>>  static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
>>  {
>> @@ -55,18 +47,16 @@ static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
>>  	switch (reg) {
>>  	case LTC2990_TINT_MSB:
>>  		/* internal temp, 0.0625 degrees/LSB, 13-bit  */
>> -		val = (val & 0x1FFF) << 3;
>> -		*result = (val * 1000) >> 7;
>> +		*result = sign_extend32(val, 12) * 1000 / 16;
>>  		break;
>>  	case LTC2990_V1_MSB:
>>  	case LTC2990_V3_MSB:
>>  		 /* Vx-Vy, 19.42uV/LSB. Depends on mode. */
>> -		*result = ltc2990_voltage_to_int(val) * 1942 / (4 * 100);
>> +		*result = sign_extend32(val, 14) * 1942 / 100;
>>  		break;
>>  	case LTC2990_VCC_MSB:
>>  		/* Vcc, 305.18μV/LSB, 2.5V offset */
>> -		*result = (ltc2990_voltage_to_int(val) * 30518 /
>> -			   (4 * 100 * 1000)) + 2500;
>> +		*result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500;
>>  		break;
>>  	default:
>>  		return -EINVAL; /* won't happen, keep compiler happy */
>
>

Re: [v3,1/3] hwmon: ltc2990: refactor value conversion

[Guenter Roeck]

On 07/11/2017 03:03 PM, Tom Levens wrote:
> 
> 
> On Sat, 8 Jul 2017, Guenter Roeck wrote:
> 
>> On Mon, Jul 03, 2017 at 06:28:58AM +0200, Tom Levens wrote:
>>> Conversion from raw values to signed integers has been refactored using
>>> bitops.h. This also fixes a bug where negative temperatures were
>>> converted incorrectly.
>>>
>>
>> Documentation/process/submitting-patches.rst, chapter 2: "Solve only one
>> problem per patch.".
>>
>> I can understand the urge to merge two sets of changes here. However,
>> that creates a problem for me: The fix should be applied to stable kernels,
>> but not the refactoring.
>>
>> Please split the patch in two, one for the bug fix and one for the
>> refactoring.
> 
> In reality the refactoring *is* the fix for this bug. I am not sure how to to fix it simply without using the bitops macro. Of course, I could fix only the temperature conversion in one patch and refactor the other two in a separate one if you prefer?
> 

If so, the subject and description are reversed. The subject should then be
something like "Fix incorrect conversion of negative temperatures",
and the description should explain that this is accomplished by using
existing API functions (then you can add "while at it, refactor voltage
conversions as well").

Thanks,
Guenter

> Cheers,
> 
>> Thanks,
>> Guenter
>>
>>> Signed-off-by: Tom Levens <tom.levens@cern.ch>
>>> ---
>>>  drivers/hwmon/ltc2990.c | 18 ++++--------------
>>>  1 file changed, 4 insertions(+), 14 deletions(-)
>>>
>>> diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c
>>> index 8f8fe05..e320d21 100644
>>> --- a/drivers/hwmon/ltc2990.c
>>> +++ b/drivers/hwmon/ltc2990.c
>>> @@ -11,6 +11,7 @@
>>>   * the chip's internal temperature and Vcc power supply voltage.
>>>   */
>>>
>>> +#include <linux/bitops.h>
>>>  #include <linux/err.h>
>>>  #include <linux/hwmon.h>
>>>  #include <linux/hwmon-sysfs.h>
>>> @@ -34,15 +35,6 @@
>>>  #define LTC2990_CONTROL_MODE_CURRENT    0x06
>>>  #define LTC2990_CONTROL_MODE_VOLTAGE    0x07
>>>
>>> -/* convert raw register value to sign-extended integer in 16-bit range */
>>> -static int ltc2990_voltage_to_int(int raw)
>>> -{
>>> -    if (raw & BIT(14))
>>> -        return -(0x4000 - (raw & 0x3FFF)) << 2;
>>> -    else
>>> -        return (raw & 0x3FFF) << 2;
>>> -}
>>> -
>>>  /* Return the converted value from the given register in uV or mC */
>>>  static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
>>>  {
>>> @@ -55,18 +47,16 @@ static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
>>>      switch (reg) {
>>>      case LTC2990_TINT_MSB:
>>>          /* internal temp, 0.0625 degrees/LSB, 13-bit  */
>>> -        val = (val & 0x1FFF) << 3;
>>> -        *result = (val * 1000) >> 7;
>>> +        *result = sign_extend32(val, 12) * 1000 / 16;
>>>          break;
>>>      case LTC2990_V1_MSB:
>>>      case LTC2990_V3_MSB:
>>>           /* Vx-Vy, 19.42uV/LSB. Depends on mode. */
>>> -        *result = ltc2990_voltage_to_int(val) * 1942 / (4 * 100);
>>> +        *result = sign_extend32(val, 14) * 1942 / 100;
>>>          break;
>>>      case LTC2990_VCC_MSB:
>>>          /* Vcc, 305.18μV/LSB, 2.5V offset */
>>> -        *result = (ltc2990_voltage_to_int(val) * 30518 /
>>> -               (4 * 100 * 1000)) + 2500;
>>> +        *result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500;
>>>          break;
>>>      default:
>>>          return -EINVAL; /* won't happen, keep compiler happy */
>>
>>