With MAX_PWM being defined to 255 the code
unsigned long period;
...
period = ctx->pwm->args.period;
state.duty_cycle = DIV_ROUND_UP(pwm * (period - 1), MAX_PWM);
calculates a too small value for duty_cycle if the configured period is
big (either by discarding the 64 bit value ctx->pwm->args.period or by
overflowing the multiplication). As this results in a too slow fan and
so maybe an overheating machine better be safe than sorry and error out
in .probe.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20201215092031.152243-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The pwm-fan driver is updated to use the recommended API.
Signed-off-by: Paul Barker <pbarker@konsulko.com>
[groeck: Dropped unused variable]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Use platform_irq_count to determine the number of fan tachometer inputs
configured in the device tree. At this stage we support either 0 or 1
inputs.
Once we have this information we only need to read the
pulses-per-revolution value if a fan tachometer is actually configured
via an IRQ value.
Also add a debug print of the IRQ number and the pulses-per-revolution
value to aid in investigating issues.
Signed-off-by: Paul Barker <pbarker@konsulko.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20201126174408.755-2-pbarker@konsulko.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
To convert the number of pulses counted into an RPM estimation, we need
to divide by the width of our measurement interval instead of
multiplying by it. If the width of the measurement interval is zero we
don't update the RPM value to avoid dividing by zero.
We also don't need to do 64-bit division, with 32-bits we can handle a
fan running at over 4 million RPM.
Signed-off-by: Paul Barker <pbarker@konsulko.com>
Link: https://lore.kernel.org/r/20201111164643.7087-1-pbarker@konsulko.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Since the PWM framework is switching struct pwm_args.period's datatype
to u64, prepare for this transition by using DIV_ROUND_UP_ULL to handle
a 64-bit dividend.
Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The pwm-fan driver stops the fan in suspend but leaves the fan on in
shutdown. It seems strange to leave the fan on in shutdown because there
is no use case in my mind and the gpio-fan driver on the other hand stops
in shutdown.
This change turns off the fan in shutdown. If anyone complains then we'll
add an optional property to switch the behavior.
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Kamil Debski <kamil@wypas.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Link: https://lore.kernel.org/r/1579534344-11694-1-git-send-email-akinobu.mita@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The PWM fan interrupt is optional, so we don't want an error message in
the kernel log if it wasn't specified.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://lore.kernel.org/r/20190828083411.2496-2-thierry.reding@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
devm_add_action_or_reset() can fail due to a memory allocation failure.
Check for it and return the error if that happens.
Fixes: 37bcec5d9f ("hwmon: (pwm-fan) Use devm_thermal_of_cooling_device_register")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Based on 3 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [kishon] [vijay] [abraham]
[i] [kishon]@[ti] [com] this program is distributed in the hope that
it will be useful but without any warranty without even the implied
warranty of merchantability or fitness for a particular purpose see
the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [graeme] [gregory]
[gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
[kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
[hk] [hemahk]@[ti] [com] this program is distributed in the hope
that it will be useful but without any warranty without even the
implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1105 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull thermal soc updates from Eduardo Valentin:
- thermal core has a new devm_* API for registering cooling devices. I
took the entire series, that is why you see changes on drivers/hwmon
in this pull (Guenter Roeck)
- rockchip thermal driver gains support to PX30 SoC (Elaine Zhang)
- the generic-adc thermal driver now considers the lookup table DT
property as optional (Jean-Francois Dagenais)
- Refactoring of tsens thermal driver (Amit Kucheria)
- Cleanups on cpu cooling driver (Daniel Lezcano)
- broadcom thermal driver dropped support to ACPI (Srinath Mannam)
- tegra thermal driver gains support to OC hw throttle and GPU throtle
(Wei Ni)
- Fixes in several thermal drivers.
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal: (59 commits)
hwmon: (pwm-fan) Use devm_thermal_of_cooling_device_register
hwmon: (npcm750-pwm-fan) Use devm_thermal_of_cooling_device_register
hwmon: (mlxreg-fan) Use devm_thermal_of_cooling_device_register
hwmon: (gpio-fan) Use devm_thermal_of_cooling_device_register
hwmon: (aspeed-pwm-tacho) Use devm_thermal_of_cooling_device_register
thermal: rcar_gen3_thermal: Fix to show correct trip points number
thermal: rcar_thermal: update calculation formula for R-Car Gen3 SoCs
thermal: cpu_cooling: Actually trace CPU load in thermal_power_cpu_get_power
thermal: rockchip: Support the PX30 SoC in thermal driver
dt-bindings: rockchip-thermal: Support the PX30 SoC compatible
thermal: rockchip: fix up the tsadc pinctrl setting error
thermal: broadcom: Remove ACPI support
thermal: Fix build error of missing devm_ioremap_resource on UM
thermal/drivers/cpu_cooling: Remove pointless field
thermal/drivers/cpu_cooling: Add Software Package Data Exchange (SPDX)
thermal/drivers/cpu_cooling: Fixup the header and copyright
thermal/drivers/cpu_cooling: Remove pointless test in power2state()
thermal: rcar_gen3_thermal: disable interrupt in .remove
thermal: rcar_gen3_thermal: fix interrupt type
thermal: Introduce devm_thermal_of_cooling_device_register
...
Use devm_thermal_of_cooling_device_register() to register the cooling
device. Also use devm_add_action_or_reset() to stop the fan on device
removal, and to disable the pwm. Introduce a local 'dev' variable in
the probe function to make the code easier to read.
As a side effect, this fixes a bug seen if pwm_fan_of_get_cooling_data()
returned an error. In that situation, the pwm was not disabled, and
the fan was not stopped. Using devm functions also ensures that the
pwm is disabled and that the fan is stopped only after the hwmon device
has been unregistered.
Cc: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Printing the error code for a failure provides a head-start for
debugging, since it's often sufficient to pinpoint the origin of the
failure. We already do this for some probe-failure messages, so let's
make the rest of them consistent.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This adds RPM support to the pwm-fan driver in order to use with
fancontrol/pwmconfig. This feature is intended for fans with a tachometer
output signal, which generate a defined number of pulses per revolution.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[groeck: Drop unused 'devattr' variable]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
In case pwm_fan_of_get_cooling_data() fails we should disable the PWM
just like in the other error cases.
Fixes: 2e5219c771 ("hwmon: (pwm-fan) Read PWM FAN configuration from device tree")
Cc: <stable@vger.kernel.org> # 4.14+
Reported-by: Guenter Rock <linux@roeck-us.net>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This adds optional regulator support to the pwm-fan driver. This is
necessary for pwm fans which are powered by a switchable supply.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Technically this is not required because disabling the PWM should be
enough. However, when support for atomic operations was implemented in
the PWM subsystem, only actual changes to the PWM channel are applied
during pwm_config(), which means that during after resume from suspend
the old settings won't be applied.
One possible solution is for the PWM driver to implement its own PM
operations such that settings from before suspend get applied on resume.
This has the disadvantage of completely ignoring any particular ordering
requirements that PWM user drivers might have, so it is best to leave it
up to the user drivers to apply the settings that they want at the
appropriate time.
Another way to solve this would be to read back the current state of the
PWM at the time of resume. That way, in case the configuration was lost
during suspend, applying the old settings in PWM user drivers would
actually get them applied because they differ from the current settings.
However, not all PWM drivers support reading the hardware state, and not
all hardware may support it.
The best workaround at this point seems to be to let PWM user drivers
tell the PWM subsystem that the PWM is turned off by, in addition to
disabling it, also setting the duty cycle to 0. This causes the resume
operation to apply a configuration that is different from the current
configuration, resulting in the proper state from before suspend getting
restored.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Probe deferrals aren't actual errors, so silence the error message in
case the PWM cannot yet be acquired.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The PWM framework has clarified the concept of reference PWM config (the
platform dependent config retrieved from the DT or the PWM lookup table)
and real PWM state.
Use pwm_get_args() when the PWM user wants to retrieve this reference
config and not the current state.
This is part of the rework allowing the PWM framework to support
hardware readout and expose real PWM state even when the PWM has just
been requested (before the user calls pwm_config/enable/disable()).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This platform driver has a OF device ID table but the OF module
alias information is not created so module autoloading won't work.
Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
pwm_config() must be called with a duty cycle of 0 prior to calling
pwm_disable() to ensure that the pwm signal is set to low.
Reported-by: Markus Reichl <m.reichl@fivetechno.de>
Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
Reviewed-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Signed-off-by: Anand Moon <linux.amoon@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Address the following sparse warnings.
drivers/hwmon/pwm-fan.c:176:5: warning:
symbol 'pwm_fan_of_get_cooling_data' was not declared. Should it be static?
drivers/hwmon/pwm-fan.c:176:5: warning:
no previous prototype for 'pwm_fan_of_get_cooling_data'
pwm_fan_of_get_cooling_data is only used in the pwm-fan driver and thus should
be declared static.
Cc: Lukasz Majewski <l.majewski@samsung.com>
Acked-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The PWM FAN device can now be used as a thermal cooling device.
Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This patch provides code for reading PWM FAN configuration data via
device tree. The pwm-fan can work with full speed when configuration
is not provided. However, errors are propagated when wrong DT bindings
are found.
Additionally the struct pwm_fan_ctx has been extended.
Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
It was necessary to decouple code handling writing to sysfs from the one
responsible for setting PWM of the fan.
Due to that, new __set_pwm() method was extracted, which is responsible for
only setting new PWM duty cycle.
Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The state of a PWM output is not clearly defined after resume. Some PWM
drivers do not restore the duty cycle upon resume, thus it is necessary to
manually restore the correct value.
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The dev_set_drvdata() call is equivalent to the platform_set_drvdata() call in
next line.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The pwm-fan driver enables control of fans connected to PWM lines.
This driver uses the PWM framework, so it is compatible with all
PWM devices that provide drivers through the PWM framework.
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Reviewed-by: Varka Bhadram <varkabhadram@gmail.com>
Reviewed-by: Tobias Klauser <tklauser@distanz.ch>
[Guenter Roeck: Last argument to devm_of_pwm_get is pointer, use NULL]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Uwe Kleine-König