power: supply: hwmon: constify pointers to hwmon_channel_info

Statically allocated array of pointed to hwmon_channel_info can be made
const for safety.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: supply: core: Simplify hwmon memory allocation

Use devm_bitmap_zalloc() instead of hand writing it.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: supply: remove duplicated argument in power_supply_hwmon_info

'HWMON_T_INPUT' and 'HWMON_T_MIN_ALARM' in power_supply_hwmon_info are
duplicated and can be removed.

Signed-off-by: Menglong Dong <dong.menglong@zte.com.cn>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: supply: core: fix memory leak in HWMON error path

In function power_supply_add_hwmon_sysfs(), psyhw->props is
allocated by bitmap_zalloc(). But this pointer is not deallocated
when devm_add_action fail, which lead to a memory leak bug. To fix
this, we replace devm_add_action with devm_add_action_or_reset.

Cc: stable@kernel.org
Fixes: e67d4dfc9ff19 ("power: supply: Add HWMON compatibility layer")
Signed-off-by: Qiushi Wu <wu000273@umn.edu>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: supply: core: tabularize HWMON temperature labels

Rework power_supply_hwmon_read_string() to check it's parameters.
This allows to extend it later with labels for other types of
measurements.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: supply: core: hide unused HWMON labels

Currently HWMON emulation shows all labels (temp and ambient temp)
regardless if power supply supports reading the values. Check that at
least one property is enabled for each label.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: supply: core: fix HWMON temperature labels

tempX_label files are swapped compared to what
power_supply_hwmon_temp_to_property() uses. Make them match.

Cc: stable@vger.kernel.org
Fixes: e67d4dfc9ff1 ("power: supply: Add HWMON compatibility layer")
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: supply: register HWMON devices with valid names

With the introduction of the HWMON compatibility layer to the power
supply framework in Linux 5.3, all power supply devices' names can be
used directly to create HWMON devices with the same names.

But HWMON has rules on allowable names that are different from those
used in the power supply framework. The dash character is forbidden, as
it is used by the libsensors library in userspace as a separator,
whereas this character is used in the device names in more than half of
the existing power supply drivers. This last case is consistent with the
typical naming usage with MFD and Device Tree.

This leads to warnings in the kernel log, with the format:

power_supply gpio-charger: hwmon: \
'gpio-charger' is not a valid name attribute, please fix

Add a protection to power_supply_add_hwmon_sysfs() that replaces any
dash in the device name with an underscore when registering with the
HWMON framework. Other forbidden characters (star, slash, space, tab,
newline) are not replaced, as they are not in common use.

Fixes: e67d4dfc9ff1 ("power: supply: Add HWMON compatibility layer")
Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: supply: Add HWMON compatibility layer

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>
Tested-by: Chris Healy <cphealy@gmail.com>
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
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>