pwm: vt8500: Make use of devm_pwmchip_alloc() function

This prepares the pwm-vt8500 driver to further changes of the pwm core
outlined in the commit introducing devm_pwmchip_alloc(). There is no
intended semantical change and the driver should behave as before.

Also convert the to_vt8500_chip() helper macro to a static inline to
get some type safety.

Link: https://lore.kernel.org/r/b203c4448db23ebad1165b7bce43ac41468c4e89.1707900770.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

pwm: vt8500: Make use of pwmchip_parent() accessor

struct pwm_chip::dev is about to change. To not have to touch this
driver in the same commit as struct pwm_chip::dev, use the accessor
function provided for exactly this purpose.

Link: https://lore.kernel.org/r/c3c45a08f2ccb8bb13b4042c73f93064876586eb.1707900770.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

pwm: vt8500: Introduce a local pwm_chip variable in .probe()

This simplifies converting the driver to pwmchip_alloc() as there is only
a single code line left that makes use of struct vt8500_chip::chip.

Link: https://lore.kernel.org/r/7d903b608609d46cf1ee1e06530f516f42af1ebb.1707900770.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

pwm: vt8500: Change prototype of a helper to prepare further changes

This prepares the driver for further changes that will make it harder to
determine the pwm_chip from a given vt8500_chip. To just not have to do
that, rework vt8500_pwm_busy_wait() to take a pwm_chip.

Link: https://lore.kernel.org/r/fb384c550b359e7707219f87872bcf36482875ff.1707900770.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

pwm: Rename pwm_apply_state() to pwm_apply_might_sleep()

In order to introduce a pwm api which can be used from atomic context,
we will need two functions for applying pwm changes:

int pwm_apply_might_sleep(struct pwm *, struct pwm_state *);
int pwm_apply_atomic(struct pwm *, struct pwm_state *);

This commit just deals with renaming pwm_apply_state(), a following
commit will introduce the pwm_apply_atomic() function.

Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> # for input
Acked-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Lee Jones <lee@kernel.org>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: Stop referencing pwm->chip

Drivers have access to the chip via a function argument already, so
there is no need to reference it via the PWM device.

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

pwm: vt8500: Simplify using devm functions

With devm_clk_get_prepared() the call to clk_unprepare() can be dropped
from the error path and the remove callback. With devm_pwmchip_add()
pwmchip_remove() can be dropped. Then the remove callback is empty and
can go away, too. With vt8500_pwm_remove() the last user of
platform_get_drvdata() is gone and so platform_set_drvdata() can be
dropped, too.

Also use dev_err_probe() for simplified (and improved) error reporting.

Link: https://lore.kernel.org/r/20230929161918.2410424-10-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: Manage owner assignment implicitly for drivers

Instead of requiring each driver to care for assigning the owner member
of struct pwm_ops, handle that implicitly using a macro. Note that the
owner member has to be moved to struct pwm_chip, as the ops structure
usually lives in read-only memory and so cannot be modified.

The upside is that new low level drivers cannot forget the assignment and
save one line each. The pwm-crc driver didn't assign .owner, that's not
a problem in practice though as the driver cannot be compiled as a
module.

Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # Intel LPSS
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> # pwm-{bcm,brcm}*.c
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> # sun4i
Acked-by: Andi Shyti <andi.shyti@kernel.org>
Acked-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp> # pwm-visconti
Acked-by: Heiko Stuebner <heiko@sntech.de> # pwm-rockchip
Acked-by: Michael Walle <michael@walle.cc> # pwm-sl28cpld
Acked-by: Neil Armstrong <neil.armstrong@linaro.org> # pwm-meson
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230804142707.412137-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: Explicitly include correct DT includes

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: vt8500: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

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

pwm: vt8500: Rename variable pointing to driver private data

Status quo is that variables of type struct vt8500_chip * are named
"vt8500", "chip". Because usually only struct pwm_device * variables
are named "pwm" and "chip" is usually used for variabled of type
struct pwm_chip *.

So consistently use the same and non-conflicting name "vt8500".

Signed-off-by: zhaoxiao <zhaoxiao@uniontech.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: vt8500: Implement .apply() callback

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>

pwm: vt8500: Rename pwm_busy_wait() to make it obviously driver-specific

The pwm_ prefix suggests that pwm_busy_wait() is a function provided by
the pwm core. Use the otherwise consistently used driver prefix for this
function, too.

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

pwm: vt8500: Only unprepare the clock after the pwmchip was removed

Until pwmchip_remove() returns the PWM is supposed to work, so
pwmchip_remove() must be called before the clock is stopped.

The return value of pwmchip_remove doesn't need to be checked because
it returns zero anyhow and I plan to make it return void soon.

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

pwm: vt8500: Drop if with an always false condition

vt8500_pwm_remove() is only called after vt8500_pwm_probe() returned
successfully. In this case driver data was set to a non-NULL value
and so chip can never be NULL.

While touching this code also put declaration and assignment in a single
line.

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

pwm: Simplify all drivers with explicit of_pwm_n_cells = 3

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>

pwm: Always allocate PWM chip base ID dynamically

Since commit 5e5da1e9fbee ("pwm: ab8500: Explicitly allocate pwm chip
base dynamically") all drivers use dynamic ID allocation explicitly. New
drivers are supposed to do the same, so remove support for driver
specified base IDs and drop all assignments in the low-level drivers.

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

pwm: vt8500: Convert to devm_platform_ioremap_resource()

Use devm_platform_ioremap_resource() to simplify code.

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

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282

Based on 1 normalized pattern(s):

this software is licensed under the terms of the gnu general public
license version 2 as published by the free software foundation and
may be copied distributed and modified under those terms 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-only

has been chosen to replace the boilerplate/reference in 285 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pwm: vt8500: Undo preparation of a clock source.

Undo preparation of a clock source if vt8500_pwm_probe() is not
successful.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: constify pwm_ops structures

Declare pwm_ops structures as const as they are only stored in the ops
field of a pwm_chip structure. This field is of type const struct pwm_ops
*, so pwm_ops structures having this property can be declared as const.
Done using Coccinelle:

@r1 disable optional_qualifier@
identifier i;
position p;
@@
static struct pwm_ops i@p={...};

@ok1@
identifier r1.i;
position p;
struct pxa_pwm_chip pwm;
struct bfin_pwm_chip bwm;
struct vt8500_chip vp;
struct imx_chip icp;
@@
(
pwm.chip.ops=&i@p
|
bwm.chip.ops=&i@p
|
vp.chip.ops=&i@p
|
icp.chip.ops=&i@p
)

@bad@
position p!={r1.p,ok1.p};
identifier r1.i;
@@
i@p

@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
+const
struct pwm_ops i;

File size details:

text data bss dec hex filename
1646 328 0 1974 7b6 drivers/pwm/pwm-imx.o
1742 224 0 1966 7ae drivers/pwm/pwm-imx.o

1941 296 0 2237 8bd drivers/pwm/pwm-pxa.o
2037 192 0 2229 8b5 drivers/pwm/pwm-pxa.o

1946 296 0 2242 8c2 drivers/pwm/pwm-vt8500.o
2050 192 0 2242 8c2 drivers/pwm/pwm-vt8500.o

The drivers/pwm/pwm-bfin.o file did not compile.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: drop owner assignment from platform_drivers

A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

pwm: vt8500: Remove unnecessary OOM messages

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm: don't check resource with devm_ioremap_resource

devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Stephen Warren <swarren@nvidia.com>

pwm: Convert to devm_ioremap_resource()

Convert all uses of devm_request_and_ioremap() to the newly introduced
devm_ioremap_resource() which provides more consistent error handling.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pwm: vt8500: Add polarity support

Add support to set polarity on PWM devices, allowing for inverted
duty cycles.

Also update the binding document to #pwm-cells = <3> to allow
passing the flags from devicetree.

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

pwm: vt8500: Register write busy test performed incorrectly

Correct operation for register writes is to perform a busy-wait
after writing the register. Currently the busy wait it performed
before, meaning subsequent register writes to bitfields may occur
before the previous field has been updated.

Also, all registers are defined as 32-bit read/write. Change
pwm_busy_wait() to use readl rather than readb.

Improve readability of code with defines for registers and bitfields.

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

pwm: vt8500: Ensure PWM clock is enabled during pwm_config

This patch corrects a bug reported by Peter Vasil.

When all PWMs are disabled, PWM module may be disabled during
calls to pwm_config. This patch enables/disables the clock in
pwm_config to ensure the module is active before register read/
writes.

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Tested-by: Peter Vasil <petervasil@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

pwm: vt8500: Fix build error

A missing '{' causes a build error in pwm-vt8500.c

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

pwm: vt8500: Update vt8500 PWM driver support

This patch updates pwm-vt8500.c to support devicetree probing and
make use of the common clock subsystem.

A binding document describing the PWM controller found on
arch-vt8500 is also included.

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

pwm: vt8500: Fix coding style issue

Fixes the following:
WARNING: Prefer pr_warn(... to pr_warning(...
pr_warning("Waiting for status bits 0x%x to clear timed out\n",

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

pwm: Convert pwm-vt8500 to use devm_* APIs

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

ARM vt8500: Move vt8500 pwm driver to pwm framework

Move the driver to drivers/pwm/ and convert it to use the framework.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>