Use devm_add_action_or_reset() instead of devres_alloc() and
devres_add(), which works the same. This will simplify the
code. There is no functional changes.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

There are no users and seems no will come of the devm_pwm_put().
Remove the function.

While at it, slightly update documentation.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Historically we have two different approaches on how to check type of fwnode.
Unify them using the latest and greatest fwnode related APIs.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

In ACPI case we may use matching by fwnode as provided via
fwnode_to_pwmchip(). This makes device_to_pwmchip() not needed
anymore.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

When we traverse the list of the registered PWM controllers,
use fwnode to match. This will help for further cleanup.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

When PWM support for ACPI has been added into the kernel, it missed
the documentation update. Hence update documentation here.

Fixes: 4a6ef8e3 ("pwm: Add support referencing PWMs from ACPI")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Add compatible string for AM64 SoC in device tree binding.
IP is compatible with ti,am3352-ecap, so adding the AM64 compatible
under enum of one of the compatible list entry.
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Convert the tiecap binding to DT schema format using json-schema.
Along with this conversion the following changes are included:
- 'clock' and 'clock-names' properties are marked required as
   driver fails to probe without these properties
- Dropped ti,am33xx-ecap as it is no longer applicable.
- 'power-domains' property is introduced and marked as optional.
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwmchip_remove() returns always 0. Don't use the value to make it
possible to eventually change the function to return void. This is a
good thing as pwmchip_remove() is usually called from a remove function
(mostly for platform devices) and their return value is ignored by the
device core anyhow.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pm_runtime_get_sync will increment pm usage counter even it failed.
Forgetting to putting operation will result in reference leak here.
Fix it by replacing it with pm_runtime_resume_and_get to keep usage
counter balanced.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

In most functions the driver data variable is called pc. Do the same in
the two remaining functions.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The .remove() function is only called after .probe() returned
successfully. In this case platform_set_drvdata() was called with a
non-NULL argument and so platfrom_get_drvdata() returns the same
non-NULL value.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwmchip_remove() always returns 0. Don't use the value to make it
possible to eventually change the function to return void. This is a
good thing as pwmchip_remove() is usually called from a remove function
(mostly for platform devices) and their return value is ignored by the
device core anyhow.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply(). This just pushes down a slightly
optimized variant of how legacy drivers are handled in the core.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

A struct berlin_pwm_chip * is now always called "bpc" (instead of "pwm"
which is usually used for struct pwm_device * or "chip" which is usually
used for struct pwm_chip *). The struct pwm_device * variables were
named "pwm_dev" or "pwm"; they are now always called "pwm".
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply(). This just pushes down a slightly
optimized variant of how legacy drivers are handled in the core.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

ecap_pwm_free is only called when a consumer releases the PWM (using
pwm_put() or pwm_free()). The consumer is expected to disable the PWM
before doing that. It's not clear if a warning about that is justified, but
if it is this is independent of the actual driver and can better be done in
the core. Also if there is a good reason it's wrong to disable the hardware
and so the call to pm_runtime_put_sync() should be dropped. Moreover there
is no matching pwm_runtime_get call and so the runtime usage counter might
become negative.

Fixes: 8e0cb05b ("pwm: pwm-tiecap: PWM driver support for ECAP APWM")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Since the PWM core uses device links (commit b2c200e3 ("pwm: Add
consumer device link")) each consumer driver that requested the PWMs is
already gone. If they called pwm_put() (as they should) the
PWMF_REQUESTED bit is not set. If they failed (which is a bug) the
PWMF_REQUESTED bit might still be set, but the driver that cared is
gone, so nothing bad happens if the PWM chip goes away even if the
PWMF_REQUESTED is still present.

So the check can be dropped.

With this change pwmchip_remove() returns always 0, so lowlevel drivers
don't need to check the return code any more. Once all drivers dropped
this check this function can be changed to return void.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

With devm_pwmchip_add() we can drop pwmchip_remove() from the device
remove callback. The latter can then go away, too and as this is the
only user of platform_get_drvdata(), the respective call to
platform_set_drvdata() can go, too.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

With devm_pwmchip_add() we can drop pwmchip_remove() from the device
remove callback. The latter can then go away, too and as this is the
only user of platform_get_drvdata(), the respective call to
platform_set_drvdata() can go, too.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The .remove() callback disables clocks that were not enabled in
.probe(). So just probing and then unbinding the driver results in a clk
enable imbalance.

So just drop the call to disable the clocks. (Which BTW was also in the
wrong order because the call makes the PWM unfunctional and so should
have come only after pwmchip_remove()).

Fixes: 9f4c8f96 ("pwm: imx: Add ipg clock operation")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

With devm_pwmchip_add() we can drop pwmchip_remove() from the device
remove callback. The latter can then go away, too and as this is the
only user of platform_get_drvdata(), the respective call to
platform_set_drvdata() can go, too.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

This potentially simplifies low-level PWM drivers.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Add compatible string for AM64 SoC in device tree binding.
EPWM IP in AM64 does not support High resolution, so named epwm instead
of ehrpwm in compatible. However IP is till compatible with features
supported by driver with ti,am3352-ehrpwm compatible.
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Convert the tiehrpwm binding to DT schema format using json-schema.
Along with this conversion the following changes are included:
- 'clock' and 'clock-names' properties are marked as required as
   driver fails to probe without these properties
- Dropped ti,am33xx-ehrpwm as it is no longer applicable.
- 'power-domains' property is introduced and marked as optional.
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Regmap operations can fail if the underlying subsystem is not working
properly (e.g. hogged I2C bus, etc.)
As this is useful information for the user, print an error message if it
happens.
Let probe fail if the first regmap_read or the first regmap_write fails.
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Previously, the last used PWM channel could change the global prescale
setting, even if other channels are already in use.

Fix it by only allowing the first enabled PWM to change the global
chip-wide prescale setting. If there is more than one channel in use,
the prescale settings resulting from the chosen periods must match.

GPIOs do not count as enabled PWMs as they are not using the prescaler
and can't change it.
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

If usage_power is set, the pca9685 driver will phase shift the
individual channels relative to their channel number. This improves EMI
because the enabled channels no longer turn on at the same time, while
still maintaining the configured duty cycle / power output.
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

If usage_power is set, the PWM driver is only required to maintain
the power output but has more freedom regarding signal form.

If supported, the signal can be optimized, for example to
improve EMI by phase shifting individual channels.
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Just using the previous callbacks to implment a similar procedure as the
legacy handling in the core.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Before pwmchip_remove() returns the PWM is expected to be functional. So
remove the pwmchip before disabling the clocks. The check for
pwmchip_remove()'s return value is dropped as this function returns
effectively always 0 and returning an error in a remove callback is
useless anyhow (as the device core ignores it and drops devm allocated
resources).
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

A consumer is expected to disable a PWM before calling pwm_put(). And if
they didn't there is hopefully a good reason (or the consumer needs
fixing). Also if disabling an enabled PWM was the right thing to do,
this should better be done in the framework instead of in each low level
driver.

So drop the hardware modification from the .remove() callback.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

With the original code a request for period = 65536000 ns and period =
32768000 ns yields the same register settings (which results in 32768000
ns) because the value for pwmc0 was miscalculated.

Also simplify using that fls(0) is 0.

Fixes: 721b5957 ("pwm: visconti: Add Toshiba Visconti SoC PWM support")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

With the previous commit there is no need for the lowlevel driver any
more to specify it it uses two or three cells. So simplify accordingly.

The only non-trival change affects the pwm-rockchip driver: It used to only
support three cells if the hardware supports polarity. Now the default
number depends on the device tree which has to match hardware anyhow
(and if it doesn't the error is just a bit delayed as a PWM handle with
an inverted setting is catched when pwm_apply_state() is called).
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

This allows to simplify all drivers that use three pwm-cells.
The only ugly side effect is that if a driver specified of_pwm_n_cells = 2
it suddenly supports device trees that use #pwm-cells = <3>. This however
isn't a bad thing because the driver doesn't need explicit support for
three cells as the core handles all the details. Also there is no such
in-tree driver.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Since the previous commit the latter function can do everything that the
former does. So simplify accordingly.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The two functions of_pwm_simple_xlate() and of_pwm_xlate_with_flags()
are quite similar. of_pwm_simple_xlate() only supports two-cell PWM
specifiers while of_pwm_xlate_with_flags() only supports PWM specifiers
with 3 or more cells. The latter can easily be modified to behave
identically to of_pwm_simple_xlate() for two-cell PWM specifiers. This
is implemented here and allows to drop of_pwm_simple_xlate() in the next
commit.

There is a small detail that is different now in the two-cell specifier
case in of_pwm_xlate_with_flags(): pwm->args.polarity is unconditionally
initialized to PWM_POLARITY_NORMAL in the latter. I didn't find a case
where this matters and doing that explicitly is the more robust
approach.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
[thierry.reding@gmail.com: fix up checkpatch warnings]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>