include/linux/i2c is not for client devices. Move the header file to a
more appropriate location.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

include/linux/i2c is not for client devices.

Move the header file to a more appropriate location.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

It is possible to update the backlight power and the brightness using
the sysfs and on writing it either returns the count or if the callback
function does not exist then returns the error code 'ENXIO'.

We have a situation where the userspace client is writing to the sysfs
to update the power and since the callback function exists the client
receives the return value as count and considers the operation to be
successful. That is correct as the write to the sysfs was successful.
But there is no way to know if the actual operation was done or not.

backlight_update_status() returns the error code if it fails. Pass that
to the userspace client who is trying to update the power so that the
client knows that the operation failed.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Pull backlight update from Lee Jones:
 "New Arctic Sand ARC2C0608 LED Backlight driver"

* tag 'backlight-next-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: Add support for Arctic Sand LED backlight driver chips
  dt-bindings: backlight: arcxcnn: Supply bindings for Arctic Sand backlight

This driver provides support for the Arctic Sand arc2c0608 chip,
and provides a framework to support future devices.

Signed-off-by: Olimpiu Dejeu <olimpiu@arcticsand.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Commit 7613c922315e308a ("backlight: pwm_bl: Move the checks for initial
power state to a separate function") not just moved some code, but made
slight changes in semantics.

If a gpiochip doesn't implement the optional .get_direction() callback,
gpiod_get_direction always returns -EINVAL, which is never equal to
GPIOF_DIR_IN, leading to the GPIO not being configured for output.

To avoid this, invert the test and check for not GPIOF_DIR_OUT instead,
like the original code did.

This restores the display on r8a7740/armadillo.

Fixes: 7613c922315e308a ("backlight: pwm_bl: Move the checks for initial power state to a separate function")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

The driver has a platform device ID table with multiple device entries,
each setting a different register address in its driver_data to control
the WLED brightness.

But the driver doesn't export these as aliases with MODULE_DEVICE_TABLE()
when the driver is built as a module, instead it just has a single alias
using MODULE_ALIAS("platform:da9052-backlight"). That is clearly wrong
since there isn't a "da9052-backlight" in the platform device ID table,
so if that device name is used, the device won't even match the driver.

So instead of having a wrong alias, export the ones in the dev ID table.

Before this patch:

$ modinfo drivers/video/backlight/da9052_bl.ko | grep alias
alias:          platform:da9052-backlight

After this patch:

$ modinfo drivers/video/backlight/da9052_bl.ko | grep alias
alias:          platform:da9052-wled3
alias:          platform:da9052-wled2
alias:          platform:da9052-wled1

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

If the PWM is not enabled the backlight initially should not be enabled
either if we have booted with DT and there is a phandle pointing to the
backlight node.

The patch extends the checks to decide if we should keep the backlight off
initially.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Move the checks to select the initial state for the backlight to a new
function and document the checks we are doing.

With the separate function it is going to be easier to fix or improve the
initial power state configuration later and it is easier to read the code.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

If adp5520_bl_setup() fails, sysfs group left unremoved.

By the way, fix overcomplicated assignement of error code.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>