pwm: pxa: Make use of devm_pwmchip_alloc() function

This prepares the pwm-pxa 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.

Link: https://lore.kernel.org/r/bee8ae436a9dfb8539637cbb7269a208f787a62a.1707900770.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

pwm: Drop useless member .of_pwm_n_cells of struct pwm_chip

Apart from the two of_xlate implementations this member is write-only.
In the of_xlate functions of_pwm_xlate_with_flags() and
of_pwm_single_xlate() it's more sensible to check for args->args_count
because this is what is actually used in the device tree.

Acked-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/53d8c545aa8f79a920358be9e72e382b3981bdc4.1704835845.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

pwm: pxa: 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>
Acked-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: pxa: Don't reimplement of_device_get_match_data()

Apart from the return type pxa_pwm_get_id_dt() reimplements
of_device_get_match_data(). Drop the former and replace the call to it
by the latter.

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>

docs: update some straggling Documentation/arm references

The Arm documentation has moved to Documentation/arch/arm; update the
last remaining references to match.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Samuel Holland <samuel@sholland.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # for pwm
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

pwm: pxa: Add reference manual link and limitations

Add a pointer to the location of reference manuals for some of the
supported chips, and add a limitations section explaining the hardware's
PWM disable behavior.

Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Doug Brown <doug@schmorgal.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20221113233639.24244-6-doug@schmorgal.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: pxa: Use abrupt shutdown mode

Switch to abrupt shutdown mode in order to stop the clock as soon as
possible when PWM is disabled. This minimizes the possibility of the
clock being re-enabled while it is still in the process of turning off,
which will result in the clock ending up erroneously disabled.

Signed-off-by: Doug Brown <doug@schmorgal.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20221113233639.24244-5-doug@schmorgal.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: pxa: Remove clk enable/disable from pxa_pwm_config

Now that pxa_pwm_apply always enables the clock first, there is no need
for pxa_pwm_config to do any clock enabling/disabling.

Signed-off-by: Doug Brown <doug@schmorgal.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20221113233639.24244-4-doug@schmorgal.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: pxa: Set duty cycle to 0 when disabling PWM

When disabling PWM, the duty cycle needs to be set to 0. This prevents
the previous duty cycle from showing up momentarily when the clock is
re-enabled next time.

Because the clock has to be running in order to configure the duty
cycle, unconditionally enable it early in pxa_pwm_apply and account for
the correct enable count at the end.

Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Doug Brown <doug@schmorgal.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20221113233639.24244-3-doug@schmorgal.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: pxa: Remove pxa_pwm_enable/disable

These functions are only acting as wrappers for clk_prepare_enable and
clk_disable_unprepare now, so remove them to simplify the driver.

Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Doug Brown <doug@schmorgal.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20221113233639.24244-2-doug@schmorgal.com
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: pxa: 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: Introduce single-PWM of_xlate function

The existing pxa driver and the upcoming addition of PWM support in the
TI sn565dsi86 DSI/eDP bridge driver both has a single PWM channel and
thereby a need for a of_xlate function with the period as its single
argument.

Introduce a common helper function in the core that can be used as
of_xlate by such drivers and migrate the pxa driver to use this.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: Steev Klimaszewski <steev@kali.org>
Tested-By: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211025170925.3096444-1-bjorn.andersson@linaro.org

pwm: pxa: Simplify using devm_pwmchip_add()

This allows to drop the platform_driver's remove function. This is the
only user of driver data so this can go away, too.

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

pwm: pxa: Always use the same variable name for driver data

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>

pwm: pxa: Drop if with an always false condition

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>

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: pxa: 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 500

Based on 2 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 version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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: Introduce the pwm_args concept

Currently the PWM core mixes the current PWM state with the per-platform
reference config (specified through the PWM lookup table, DT definition
or directly hardcoded in PWM drivers).

Create a struct pwm_args to store this reference configuration, so that
PWM users can differentiate between the current and reference
configurations.

Patch all places where pwm->args should be initialized. We keep the
pwm_set_polarity/period() calls until all PWM users are patched to use
pwm_args instead of pwm_get_period/polarity().

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[thierry.reding@gmail.com: reword kerneldoc comments]
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: pxa: 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>

pwm: pxa: Constify OF match table

The table is never modified and all OF functions that use it take a
const struct of_device_id *.

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

pwm: pxa: Fix typo "pwm" -> "PWM"

Being an abbreviation, PWM should always be capitalized in prose.

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

Revert "pwm: pxa: Use of_match_ptr()"

This reverts commit 8468949cddcdbb1b1b1bc552aefceb252078ceb1.

The OF match table dummy for non-OF configurations cannot be removed
because it is still used by the pxa_pwm_get_id_dt() function.

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

pwm: pxa: Use of_match_ptr()

Use of_match_ptr(), because of_match_ptr() returns NULL pointer
when CONFIG_OF is disabled.

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

pwm: pxa: remove unnecessary space before tabs

Remove unnecessary space before tabs in order to fix the following
checkpatch warning.

WARNING: please, no space before tabs

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

pwm: pxa: Add device tree support

This patch adds device tree support to the PXA's PWM driver. Nothing
needs to be extracted from the device tree node by the PWM device.
Client devices need only specify the period; the per-chip index is
implicitly zero because one device node must be present for each PWM
output in use. This approach is more convenient due to the wide
variability in the number of PWM channels present across the various PXA
variants, and is made possible by the fact that the register sets for
each PWM channel are segregated from each other. An of_xlate() method
is added to parse this single-cell node. The existing ID table is
reused for the match table data.

Tested on a Palm Treo 680 (both platform data and DT cases).

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwm: pxa: Use module_platform_driver

Commit 76abbdde2d95a3807d0dc6bf9f84d03d0dbd4f3d

pwm: Add sysfs interface

causes a kernel oops due to a null pointer dereference on PXA platforms.
This happens because the class added by the patch is registered in a
subsys_initcall (initcall4), but the pxa pwm driver is registered in
arch_initcall (initcall3). If the class is not registered before the
driver probe function runs, the oops occurs in device_add() when the
uninitialized pointers in struct class are dereferenced. I don't see a
reason that the driver must be an arch_initcall, so this patch makes it
a regular module_platform_driver (initcall6), preventing the oops.

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Marek Vasut <marex@denx.de>
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: pxa: Remove PWM_ID_BASE macro

PWM_ID_BASE() is not used after convert to PWM framework, remove it.
Also update driver_data field of struct platform_device_id accordingly.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

pwm: pxa: Remove clk_enabled field from struct pxa_pwm_chip

clk_enable/clk_disable maintain an enable_count, clk_prepare and clk_unprepare
also maintain a prepare_count. These APIs will do prepare/enable when the first
user calling these APIs, and do disable/unprepare when the corresponding counter
reach 0. Thus We don't need to maintain a clk_enabled counter here.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

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: remove use of __devexit

CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pwm: remove use of __devinit

CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pwm: remove use of __devexit_p

CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pwm: Check for negative duty-cycle and period

Make sure the duty-cycle and period passed in are not negative. This
should eventually be made implicit by making them unsigned. While at
it, the drivers' .config() implementations can have the equivalent
checks removed.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Axel Lin <axel.lin@gmail.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Cc: Jonghwan Choi <jhbird.choi@samsung.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: "Philip, Avinash" <avinashphilip@ti.com>
Cc: Vaibhav Bedia <vaibhav.bedia@ti.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>

pwm: pxa: Propagate pwmchip_remove() error

If the pwmchip_remove() call fails, propagate the error to the driver's
remove callback. This is required to prevent the module from being
unloaded if a PWM provided by the driver is still in use.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

pwm: Convert pwm-pxa to use devm_* APIs

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

pwm: Move PXA PWM driver to PWM framework

This commit moves the PXA PWM driver to the drivers/pwm subdirectory and
converts it to use the new PWM framework.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>