backlight: hx8357: Utilise temporary variable for struct device

We have a temporary variable to keep pointer to struct device.
Utilise it inside the ->probe() implementation.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20240201144951.294215-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Lee Jones <lee@kernel.org>

backlight: hx8357: Make use of dev_err_probe()

Simplify the error handling in probe function by switching from
dev_err() to dev_err_probe().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20240201144951.294215-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Lee Jones <lee@kernel.org>

backlight: hx8357: Move OF table closer to its consumer

Move OF table near to the user.

While at it, drop comma at terminator entry.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20240201144951.294215-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Lee Jones <lee@kernel.org>

backlight: hx8357: Make use of device properties

Convert the module to be property provider agnostic and allow
it to be used on non-OF platforms.

Include mod_devicetable.h explicitly to replace the dropped of.h
which included mod_devicetable.h indirectly.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20240201144951.294215-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Lee Jones <lee@kernel.org>

backlight: hx8357: Fix potential NULL pointer dereference

The "im" pins are optional. Add missing check in the hx8357_probe().

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/642e1230-3358-4006-a17f-3f297897ae74@moroto.mountain
Fixes: 7d84a63a39b7 ("backlight: hx8357: Convert to agnostic GPIO API")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20240114143921.550736-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Lee Jones <lee@kernel.org>

backlight: hx8357: Convert to agnostic GPIO API

The of_gpio.h is going to be removed. In preparation of that convert
the driver to the agnostic API.

Fixes: fbbbcd177a27 ("gpiolib: of: add quirk for locating reset lines with legacy bindings")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20231207161513.3195509-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Lee Jones <lee@kernel.org>

backlight: hx8357: Use of_property_present() for testing DT property presence

It is preferred to use typed property access functions (i.e.
of_property_read_<type> functions) rather than low-level
of_get_property/of_find_property functions for reading properties. As
part of this, convert of_get_property/of_find_property calls to the
recently added of_property_present() helper when we just want to test
for presence of a property and nothing more.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230310144730.1546101-1-robh@kernel.org

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 71

Based on 1 normalized pattern(s):

licensed under the gplv2 or later

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 5 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
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/20190520071859.659568621@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

backlight: hx8357: 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>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/backlight/hx8357.c: remove redundant of_match_ptr

'hx8357_dt_ids' is always compiled in. Hence of_match_ptr is not needed.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: hx8357: use devm_lcd_device_register()

Use devm_lcd_device_register() to make cleanup paths simpler, and remove
unnecessary remove().

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fb: backlight: HX8357: Add HX8369 support

Add support for the Himax HX8369 controller as it is quite similar to the
hx8357.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

video: hx8357: Make IM pins optional

The IM pins of the HX8357 controller are used to define the interface
used to feed pixel stream to the LCD panel.

Most of the time, these pins are directly routed to either the ground or
the VCC to set their values.

Remove the need to assign GPIOs to these pins when we are in such a case.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

fb: backlight: add the Himax HX-8357B LCD controller

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Brian Lilly <brian@crystalfontz.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>