[PATCH v3 0/2] HWMON compatibility layer for power supplies

[PATCH v3 0/2] HWMON compatibility layer for power supplies

[Andrey Smirnov]

Everyone:

This small series contains the code I wrote to expose various power
supply sensors via HWMON layer in order to be able to access all of
the sensors in the system with libsensors.

Changes since [v2]:

  - Added missing static specified to devm_power_supply_add_hwmon_sysfs()
  
  - Collected Reviewed-by from Guenter

Changes since [v1]:

  - All multiplications converted to use check_mul_overflow()

  - All divisions converted to use DIV_ROUND_CLOSEST()

  - Places that were ignoring errors now don't

  - Alphabetized include list

[v2] lkml.kernel.org/r/20190531011620.9383-1-andrew.smirnov@gmail.com
[v1] lkml.kernel.org/r/20190529071112.16849-1-andrew.smirnov@gmail.com

Thanks,
Andrey Smirnov

Andrey Smirnov (2):
  power: supply: Add HWMON compatibility layer
  power: supply: ucs1002: Add HWMON interface

 drivers/power/supply/Kconfig              |  14 +
 drivers/power/supply/Makefile             |   1 +
 drivers/power/supply/power_supply_hwmon.c | 349 ++++++++++++++++++++++
 drivers/power/supply/ucs1002_power.c      |   6 +
 include/linux/power_supply.h              |   9 +
 5 files changed, 379 insertions(+)
 create mode 100644 drivers/power/supply/power_supply_hwmon.c

-- 
2.21.0

[PATCH v3 1/2] power: supply: Add HWMON compatibility layer

[Andrey Smirnov]

Add code implementing HWMON adapter/compatibility layer to allow
expositing various sensors present on power supply devices via HWMON
subsystem. This is done in order to allow userspace to use single
ABI/library(libsensors) to access/manipulate all of the sensors of the
system.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Cory Tusar <cory.tusar@zii.aero>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-pm@vger.kernel.org
---
 drivers/power/supply/Kconfig              |  14 +
 drivers/power/supply/Makefile             |   1 +
 drivers/power/supply/power_supply_hwmon.c | 349 ++++++++++++++++++++++
 include/linux/power_supply.h              |   9 +
 4 files changed, 373 insertions(+)
 create mode 100644 drivers/power/supply/power_supply_hwmon.c

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index c614c8a196f3..0550cedb53c9 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -14,6 +14,20 @@ config POWER_SUPPLY_DEBUG
 	  Say Y here to enable debugging messages for power supply class
 	  and drivers.
 
+config POWER_SUPPLY_HWMON
+	bool
+	prompt "Expose power supply sensors as hwmon device"
+	depends on HWMON=y || HWMON=POWER_SUPPLY
+	default y
+	help
+	  This options enables API that allows sensors found on a
+	  power supply device (current, voltage, temperature) to be
+	  exposed as a hwmon device.
+
+	  Say 'Y' here if you want power supplies to
+	  have hwmon sysfs interface too.
+
+
 config PDA_POWER
 	tristate "Generic PDA/phone power driver"
 	depends on !S390
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index c56803a9e4fe..0a87cfe49b21 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -6,6 +6,7 @@ power_supply-$(CONFIG_SYSFS)		+= power_supply_sysfs.o
 power_supply-$(CONFIG_LEDS_TRIGGERS)	+= power_supply_leds.o
 
 obj-$(CONFIG_POWER_SUPPLY)	+= power_supply.o
+obj-$(CONFIG_POWER_SUPPLY_HWMON) += power_supply_hwmon.o
 obj-$(CONFIG_GENERIC_ADC_BATTERY)	+= generic-adc-battery.o
 
 obj-$(CONFIG_PDA_POWER)		+= pda_power.o
diff --git a/drivers/power/supply/power_supply_hwmon.c b/drivers/power/supply/power_supply_hwmon.c
new file mode 100644
index 000000000000..3451b997367d
--- /dev/null
+++ b/drivers/power/supply/power_supply_hwmon.c
@@ -0,0 +1,349 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  power_supply_hwmon.c - power supply hwmon support.
+ */
+
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/power_supply.h>
+#include <linux/slab.h>
+
+struct power_supply_hwmon {
+	struct power_supply *psy;
+	unsigned long *props;
+};
+
+static int power_supply_hwmon_in_to_property(u32 attr)
+{
+	switch (attr) {
+	case hwmon_in_average:
+		return POWER_SUPPLY_PROP_VOLTAGE_AVG;
+	case hwmon_in_min:
+		return POWER_SUPPLY_PROP_VOLTAGE_MIN;
+	case hwmon_in_max:
+		return POWER_SUPPLY_PROP_VOLTAGE_MAX;
+	case hwmon_in_input:
+		return POWER_SUPPLY_PROP_VOLTAGE_NOW;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int power_supply_hwmon_curr_to_property(u32 attr)
+{
+	switch (attr) {
+	case hwmon_curr_average:
+		return POWER_SUPPLY_PROP_CURRENT_AVG;
+	case hwmon_curr_max:
+		return POWER_SUPPLY_PROP_CURRENT_MAX;
+	case hwmon_curr_input:
+		return POWER_SUPPLY_PROP_CURRENT_NOW;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int power_supply_hwmon_temp_to_property(u32 attr, int channel)
+{
+	if (channel) {
+		switch (attr) {
+		case hwmon_temp_input:
+			return POWER_SUPPLY_PROP_TEMP_AMBIENT;
+		case hwmon_temp_min_alarm:
+			return POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MIN;
+		case hwmon_temp_max_alarm:
+			return POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MAX;
+		default:
+			break;
+		}
+	} else {
+		switch (attr) {
+		case hwmon_temp_input:
+			return POWER_SUPPLY_PROP_TEMP;
+		case hwmon_temp_max:
+			return POWER_SUPPLY_PROP_TEMP_MAX;
+		case hwmon_temp_min:
+			return POWER_SUPPLY_PROP_TEMP_MIN;
+		case hwmon_temp_min_alarm:
+			return POWER_SUPPLY_PROP_TEMP_ALERT_MIN;
+		case hwmon_temp_max_alarm:
+			return POWER_SUPPLY_PROP_TEMP_ALERT_MAX;
+		default:
+			break;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int
+power_supply_hwmon_to_property(enum hwmon_sensor_types type,
+			       u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_in:
+		return power_supply_hwmon_in_to_property(attr);
+	case hwmon_curr:
+		return power_supply_hwmon_curr_to_property(attr);
+	case hwmon_temp:
+		return power_supply_hwmon_temp_to_property(attr, channel);
+	default:
+		return -EINVAL;
+	}
+}
+
+static bool power_supply_hwmon_is_a_label(enum hwmon_sensor_types type,
+					   u32 attr)
+{
+	return type == hwmon_temp && attr == hwmon_temp_label;
+}
+
+static bool power_supply_hwmon_is_writable(enum hwmon_sensor_types type,
+					   u32 attr)
+{
+	switch (type) {
+	case hwmon_in:
+		return attr == hwmon_in_min ||
+		       attr == hwmon_in_max;
+	case hwmon_curr:
+		return attr == hwmon_curr_max;
+	case hwmon_temp:
+		return attr == hwmon_temp_max ||
+		       attr == hwmon_temp_min ||
+		       attr == hwmon_temp_min_alarm ||
+		       attr == hwmon_temp_max_alarm;
+	default:
+		return false;
+	}
+}
+
+static umode_t power_supply_hwmon_is_visible(const void *data,
+					     enum hwmon_sensor_types type,
+					     u32 attr, int channel)
+{
+	const struct power_supply_hwmon *psyhw = data;
+	int prop;
+
+
+	if (power_supply_hwmon_is_a_label(type, attr))
+		return 0444;
+
+	prop = power_supply_hwmon_to_property(type, attr, channel);
+	if (prop < 0 || !test_bit(prop, psyhw->props))
+		return 0;
+
+	if (power_supply_property_is_writeable(psyhw->psy, prop) > 0 &&
+	    power_supply_hwmon_is_writable(type, attr))
+		return 0644;
+
+	return 0444;
+}
+
+static int power_supply_hwmon_read_string(struct device *dev,
+					  enum hwmon_sensor_types type,
+					  u32 attr, int channel,
+					  const char **str)
+{
+	*str = channel ? "temp" : "temp ambient";
+	return 0;
+}
+
+static int
+power_supply_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+			u32 attr, int channel, long *val)
+{
+	struct power_supply_hwmon *psyhw = dev_get_drvdata(dev);
+	struct power_supply *psy = psyhw->psy;
+	union power_supply_propval pspval;
+	int ret, prop;
+
+	prop = power_supply_hwmon_to_property(type, attr, channel);
+	if (prop < 0)
+		return prop;
+
+	ret  = power_supply_get_property(psy, prop, &pspval);
+	if (ret)
+		return ret;
+
+	switch (type) {
+	/*
+	 * Both voltage and current is reported in units of
+	 * microvolts/microamps, so we need to adjust it to
+	 * milliamps(volts)
+	 */
+	case hwmon_curr:
+	case hwmon_in:
+		pspval.intval = DIV_ROUND_CLOSEST(pspval.intval, 1000);
+		break;
+	/*
+	 * Temp needs to be converted from 1/10 C to milli-C
+	 */
+	case hwmon_temp:
+		if (check_mul_overflow(pspval.intval, 100,
+				       &pspval.intval))
+			return -EOVERFLOW;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	*val = pspval.intval;
+
+	return 0;
+}
+
+static int
+power_supply_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
+			 u32 attr, int channel, long val)
+{
+	struct power_supply_hwmon *psyhw = dev_get_drvdata(dev);
+	struct power_supply *psy = psyhw->psy;
+	union power_supply_propval pspval;
+	int prop;
+
+	prop = power_supply_hwmon_to_property(type, attr, channel);
+	if (prop < 0)
+		return prop;
+
+	pspval.intval = val;
+
+	switch (type) {
+	/*
+	 * Both voltage and current is reported in units of
+	 * microvolts/microamps, so we need to adjust it to
+	 * milliamps(volts)
+	 */
+	case hwmon_curr:
+	case hwmon_in:
+		if (check_mul_overflow(pspval.intval, 1000,
+				       &pspval.intval))
+			return -EOVERFLOW;
+		break;
+	/*
+	 * Temp needs to be converted from 1/10 C to milli-C
+	 */
+	case hwmon_temp:
+		pspval.intval = DIV_ROUND_CLOSEST(pspval.intval, 100);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return power_supply_set_property(psy, prop, &pspval);
+}
+
+static const struct hwmon_ops power_supply_hwmon_ops = {
+	.is_visible	= power_supply_hwmon_is_visible,
+	.read		= power_supply_hwmon_read,
+	.write		= power_supply_hwmon_write,
+	.read_string	= power_supply_hwmon_read_string,
+};
+
+static const struct hwmon_channel_info *power_supply_hwmon_info[] = {
+	HWMON_CHANNEL_INFO(temp,
+			   HWMON_T_LABEL     |
+			   HWMON_T_INPUT     |
+			   HWMON_T_MAX       |
+			   HWMON_T_MIN       |
+			   HWMON_T_MIN_ALARM |
+			   HWMON_T_MIN_ALARM,
+
+			   HWMON_T_LABEL     |
+			   HWMON_T_INPUT     |
+			   HWMON_T_MIN_ALARM |
+			   HWMON_T_LABEL     |
+			   HWMON_T_MAX_ALARM),
+
+	HWMON_CHANNEL_INFO(curr,
+			   HWMON_C_AVERAGE |
+			   HWMON_C_MAX     |
+			   HWMON_C_INPUT),
+
+	HWMON_CHANNEL_INFO(in,
+			   HWMON_I_AVERAGE |
+			   HWMON_I_MIN     |
+			   HWMON_I_MAX     |
+			   HWMON_I_INPUT),
+	NULL
+};
+
+static const struct hwmon_chip_info power_supply_hwmon_chip_info = {
+	.ops = &power_supply_hwmon_ops,
+	.info = power_supply_hwmon_info,
+};
+
+static void power_supply_hwmon_bitmap_free(void *data)
+{
+	bitmap_free(data);
+}
+
+int devm_power_supply_add_hwmon_sysfs(struct power_supply *psy)
+{
+	const struct power_supply_desc *desc = psy->desc;
+	struct power_supply_hwmon *psyhw;
+	struct device *dev = &psy->dev;
+	struct device *hwmon;
+	int ret, i;
+
+	if (!devres_open_group(dev, NULL, GFP_KERNEL))
+		return -ENOMEM;
+
+	psyhw = devm_kzalloc(dev, sizeof(*psyhw), GFP_KERNEL);
+	if (!psyhw) {
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	psyhw->psy = psy;
+	psyhw->props = bitmap_zalloc(POWER_SUPPLY_PROP_TIME_TO_FULL_AVG + 1,
+				     GFP_KERNEL);
+	if (!psyhw->props) {
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	ret = devm_add_action(dev, power_supply_hwmon_bitmap_free,
+			      psyhw->props);
+	if (ret)
+		goto error;
+
+	for (i = 0; i < desc->num_properties; i++) {
+		const enum power_supply_property prop = desc->properties[i];
+
+		switch (prop) {
+		case POWER_SUPPLY_PROP_CURRENT_AVG:
+		case POWER_SUPPLY_PROP_CURRENT_MAX:
+		case POWER_SUPPLY_PROP_CURRENT_NOW:
+		case POWER_SUPPLY_PROP_TEMP:
+		case POWER_SUPPLY_PROP_TEMP_MAX:
+		case POWER_SUPPLY_PROP_TEMP_MIN:
+		case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
+		case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
+		case POWER_SUPPLY_PROP_TEMP_AMBIENT:
+		case POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MIN:
+		case POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MAX:
+		case POWER_SUPPLY_PROP_VOLTAGE_AVG:
+		case POWER_SUPPLY_PROP_VOLTAGE_MIN:
+		case POWER_SUPPLY_PROP_VOLTAGE_MAX:
+		case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+			set_bit(prop, psyhw->props);
+			break;
+		default:
+			break;
+		}
+	}
+
+	hwmon = devm_hwmon_device_register_with_info(dev, psy->desc->name,
+						psyhw,
+						&power_supply_hwmon_chip_info,
+						NULL);
+	ret = PTR_ERR_OR_ZERO(hwmon);
+	if (ret)
+		goto error;
+
+	devres_remove_group(dev, NULL);
+	return 0;
+error:
+	devres_release_group(dev, NULL);
+	return ret;
+}
diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index bdab14c7ca4d..39343bc4a3f8 100644
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -475,4 +475,13 @@ static inline bool power_supply_is_watt_property(enum power_supply_property psp)
 	return 0;
 }
 
+#ifdef CONFIG_POWER_SUPPLY_HWMON
+int devm_power_supply_add_hwmon_sysfs(struct power_supply *psy);
+#else
+static int devm_power_supply_add_hwmon_sysfs(struct power_supply *psy)
+{
+	return 0;
+}
+#endif
+
 #endif /* __LINUX_POWER_SUPPLY_H__ */
-- 
2.21.0

[PATCH v3 2/2] power: supply: ucs1002: Add HWMON interface

[Andrey Smirnov]

Expose current sensors found on UCS1002 via HWMON.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Cory Tusar <cory.tusar@zii.aero>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-pm@vger.kernel.org
---
 drivers/power/supply/ucs1002_power.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/power/supply/ucs1002_power.c b/drivers/power/supply/ucs1002_power.c
index 677f20a4d76f..a4b6b37549cf 100644
--- a/drivers/power/supply/ucs1002_power.c
+++ b/drivers/power/supply/ucs1002_power.c
@@ -571,6 +571,12 @@ static int ucs1002_probe(struct i2c_client *client,
 		return ret;
 	}
 
+	ret = devm_power_supply_add_hwmon_sysfs(info->charger);
+	if (ret) {
+		dev_err(dev, "Failed to add hmwon attributes: %d\n", ret);
+		return ret;
+	}
+
 	ret = regmap_read(info->regmap, UCS1002_REG_PIN_STATUS, &regval);
 	if (ret) {
 		dev_err(dev, "Failed to read pin status: %d\n", ret);
-- 
2.21.0

Re: [PATCH v3 2/2] power: supply: ucs1002: Add HWMON interface

[Andrew F. Davis]

On 6/5/19 3:23 AM, Andrey Smirnov wrote:
> Expose current sensors found on UCS1002 via HWMON.
> 
> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> Reviewed-by: Guenter Roeck <linux@roeck-us.net>
> Cc: Chris Healy <cphealy@gmail.com>
> Cc: Cory Tusar <cory.tusar@zii.aero>
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Fabio Estevam <fabio.estevam@nxp.com>
> Cc: Guenter Roeck <linux@roeck-us.net>
> Cc: Sebastian Reichel <sre@kernel.org>
> Cc: linux-kernel@vger.kernel.org
> Cc: linux-pm@vger.kernel.org
> ---
>   drivers/power/supply/ucs1002_power.c | 6 ++++++
>   1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/power/supply/ucs1002_power.c b/drivers/power/supply/ucs1002_power.c
> index 677f20a4d76f..a4b6b37549cf 100644
> --- a/drivers/power/supply/ucs1002_power.c
> +++ b/drivers/power/supply/ucs1002_power.c
> @@ -571,6 +571,12 @@ static int ucs1002_probe(struct i2c_client *client,
>   		return ret;
>   	}
>   
> +	ret = devm_power_supply_add_hwmon_sysfs(info->charger);

Could this be added to the core power supply framework on registering so 
all devices get this, vs each driver having to add this line?

Andrew

> +	if (ret) {
> +		dev_err(dev, "Failed to add hmwon attributes: %d\n", ret);
> +		return ret;
> +	}
> +
>   	ret = regmap_read(info->regmap, UCS1002_REG_PIN_STATUS, &regval);
>   	if (ret) {
>   		dev_err(dev, "Failed to read pin status: %d\n", ret);
> 

Re: [PATCH v3 2/2] power: supply: ucs1002: Add HWMON interface

[Andrey Smirnov]

On Wed, Jun 5, 2019 at 9:26 AM Andrew F. Davis <afd@ti.com> wrote:
>
> On 6/5/19 3:23 AM, Andrey Smirnov wrote:
> > Expose current sensors found on UCS1002 via HWMON.
> >
> > Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> > Reviewed-by: Guenter Roeck <linux@roeck-us.net>
> > Cc: Chris Healy <cphealy@gmail.com>
> > Cc: Cory Tusar <cory.tusar@zii.aero>
> > Cc: Lucas Stach <l.stach@pengutronix.de>
> > Cc: Fabio Estevam <fabio.estevam@nxp.com>
> > Cc: Guenter Roeck <linux@roeck-us.net>
> > Cc: Sebastian Reichel <sre@kernel.org>
> > Cc: linux-kernel@vger.kernel.org
> > Cc: linux-pm@vger.kernel.org
> > ---
> >   drivers/power/supply/ucs1002_power.c | 6 ++++++
> >   1 file changed, 6 insertions(+)
> >
> > diff --git a/drivers/power/supply/ucs1002_power.c b/drivers/power/supply/ucs1002_power.c
> > index 677f20a4d76f..a4b6b37549cf 100644
> > --- a/drivers/power/supply/ucs1002_power.c
> > +++ b/drivers/power/supply/ucs1002_power.c
> > @@ -571,6 +571,12 @@ static int ucs1002_probe(struct i2c_client *client,
> >               return ret;
> >       }
> >
> > +     ret = devm_power_supply_add_hwmon_sysfs(info->charger);
>
> Could this be added to the core power supply framework on registering so
> all devices get this, vs each driver having to add this line?
>

I'd say it is up to Sebastian to decide if this should be opt-out
rather than opt-in. I have no objections to either approach.

Thanks,
Andrey Smirnov

Re: [PATCH v3 2/2] power: supply: ucs1002: Add HWMON interface

[Guenter Roeck]

On Wed, Jun 05, 2019 at 10:47:25AM -0700, Andrey Smirnov wrote:
> On Wed, Jun 5, 2019 at 9:26 AM Andrew F. Davis <afd@ti.com> wrote:
> >
> > On 6/5/19 3:23 AM, Andrey Smirnov wrote:
> > > Expose current sensors found on UCS1002 via HWMON.
> > >
> > > Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> > > Reviewed-by: Guenter Roeck <linux@roeck-us.net>
> > > Cc: Chris Healy <cphealy@gmail.com>
> > > Cc: Cory Tusar <cory.tusar@zii.aero>
> > > Cc: Lucas Stach <l.stach@pengutronix.de>
> > > Cc: Fabio Estevam <fabio.estevam@nxp.com>
> > > Cc: Guenter Roeck <linux@roeck-us.net>
> > > Cc: Sebastian Reichel <sre@kernel.org>
> > > Cc: linux-kernel@vger.kernel.org
> > > Cc: linux-pm@vger.kernel.org
> > > ---
> > >   drivers/power/supply/ucs1002_power.c | 6 ++++++
> > >   1 file changed, 6 insertions(+)
> > >
> > > diff --git a/drivers/power/supply/ucs1002_power.c b/drivers/power/supply/ucs1002_power.c
> > > index 677f20a4d76f..a4b6b37549cf 100644
> > > --- a/drivers/power/supply/ucs1002_power.c
> > > +++ b/drivers/power/supply/ucs1002_power.c
> > > @@ -571,6 +571,12 @@ static int ucs1002_probe(struct i2c_client *client,
> > >               return ret;
> > >       }
> > >
> > > +     ret = devm_power_supply_add_hwmon_sysfs(info->charger);
> >
> > Could this be added to the core power supply framework on registering so
> > all devices get this, vs each driver having to add this line?
> >
> 
> I'd say it is up to Sebastian to decide if this should be opt-out
> rather than opt-in. I have no objections to either approach.
> 

Same here, and agreed.

Guenter

Re: [PATCH v3 2/2] power: supply: ucs1002: Add HWMON interface

[Sebastian Reichel]

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Hi,

On Wed, Jun 05, 2019 at 11:39:45AM -0700, Guenter Roeck wrote:
> On Wed, Jun 05, 2019 at 10:47:25AM -0700, Andrey Smirnov wrote:
> > On Wed, Jun 5, 2019 at 9:26 AM Andrew F. Davis <afd@ti.com> wrote:
> > >
> > > On 6/5/19 3:23 AM, Andrey Smirnov wrote:
> > > > Expose current sensors found on UCS1002 via HWMON.
> > > >
> > > > Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> > > > Reviewed-by: Guenter Roeck <linux@roeck-us.net>
> > > > Cc: Chris Healy <cphealy@gmail.com>
> > > > Cc: Cory Tusar <cory.tusar@zii.aero>
> > > > Cc: Lucas Stach <l.stach@pengutronix.de>
> > > > Cc: Fabio Estevam <fabio.estevam@nxp.com>
> > > > Cc: Guenter Roeck <linux@roeck-us.net>
> > > > Cc: Sebastian Reichel <sre@kernel.org>
> > > > Cc: linux-kernel@vger.kernel.org
> > > > Cc: linux-pm@vger.kernel.org
> > > > ---
> > > >   drivers/power/supply/ucs1002_power.c | 6 ++++++
> > > >   1 file changed, 6 insertions(+)
> > > >
> > > > diff --git a/drivers/power/supply/ucs1002_power.c b/drivers/power/supply/ucs1002_power.c
> > > > index 677f20a4d76f..a4b6b37549cf 100644
> > > > --- a/drivers/power/supply/ucs1002_power.c
> > > > +++ b/drivers/power/supply/ucs1002_power.c
> > > > @@ -571,6 +571,12 @@ static int ucs1002_probe(struct i2c_client *client,
> > > >               return ret;
> > > >       }
> > > >
> > > > +     ret = devm_power_supply_add_hwmon_sysfs(info->charger);
> > >
> > > Could this be added to the core power supply framework on registering so
> > > all devices get this, vs each driver having to add this line?
> > >
> > 
> > I'd say it is up to Sebastian to decide if this should be opt-out
> > rather than opt-in. I have no objections to either approach.
> > 
> 
> Same here, and agreed.

I think this should be registered in power_supply_register() and
free'd in power_supply_unregister(). It's not device specific at
all and the functionality can be configured via Kconfig.

-- Sebastian

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Re: [PATCH v3 2/2] power: supply: ucs1002: Add HWMON interface

[Andrey Smirnov]

On Tue, Jun 11, 2019 at 12:46 PM Sebastian Reichel <sre@kernel.org> wrote:
>
> Hi,
>
> On Wed, Jun 05, 2019 at 11:39:45AM -0700, Guenter Roeck wrote:
> > On Wed, Jun 05, 2019 at 10:47:25AM -0700, Andrey Smirnov wrote:
> > > On Wed, Jun 5, 2019 at 9:26 AM Andrew F. Davis <afd@ti.com> wrote:
> > > >
> > > > On 6/5/19 3:23 AM, Andrey Smirnov wrote:
> > > > > Expose current sensors found on UCS1002 via HWMON.
> > > > >
> > > > > Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> > > > > Reviewed-by: Guenter Roeck <linux@roeck-us.net>
> > > > > Cc: Chris Healy <cphealy@gmail.com>
> > > > > Cc: Cory Tusar <cory.tusar@zii.aero>
> > > > > Cc: Lucas Stach <l.stach@pengutronix.de>
> > > > > Cc: Fabio Estevam <fabio.estevam@nxp.com>
> > > > > Cc: Guenter Roeck <linux@roeck-us.net>
> > > > > Cc: Sebastian Reichel <sre@kernel.org>
> > > > > Cc: linux-kernel@vger.kernel.org
> > > > > Cc: linux-pm@vger.kernel.org
> > > > > ---
> > > > >   drivers/power/supply/ucs1002_power.c | 6 ++++++
> > > > >   1 file changed, 6 insertions(+)
> > > > >
> > > > > diff --git a/drivers/power/supply/ucs1002_power.c b/drivers/power/supply/ucs1002_power.c
> > > > > index 677f20a4d76f..a4b6b37549cf 100644
> > > > > --- a/drivers/power/supply/ucs1002_power.c
> > > > > +++ b/drivers/power/supply/ucs1002_power.c
> > > > > @@ -571,6 +571,12 @@ static int ucs1002_probe(struct i2c_client *client,
> > > > >               return ret;
> > > > >       }
> > > > >
> > > > > +     ret = devm_power_supply_add_hwmon_sysfs(info->charger);
> > > >
> > > > Could this be added to the core power supply framework on registering so
> > > > all devices get this, vs each driver having to add this line?
> > > >
> > >
> > > I'd say it is up to Sebastian to decide if this should be opt-out
> > > rather than opt-in. I have no objections to either approach.
> > >
> >
> > Same here, and agreed.
>
> I think this should be registered in power_supply_register() and
> free'd in power_supply_unregister(). It's not device specific at
> all and the functionality can be configured via Kconfig.
>

Sure, will do in v4.

Thanks,
Andrey Smirnov

Re: [PATCH v3 0/2] HWMON compatibility layer for power supplies

[Chris Healy]

> This small series contains the code I wrote to expose various power
> supply sensors via HWMON layer in order to be able to access all of
> the sensors in the system with libsensors.
>
> Changes since [v2]:

Full series is tested using the UCS1002.

Tested-by: cphealy@gmail.com <cphealy@gmail.com>