Now that the potential use-after-free issue is resolved we can use
devres for LED registration in this driver.

By using devres version of LED registering function we can remove the
.remove method from this driver.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Tested-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Instead of registering LED under the MFD device, this driver sets the
parent of the LED it is registering to the parent of the MFD device (the
I2C client device).

Because of this we cannot use devres for LED registration, since it can
result in use-after-free, see commit
a0972fff ("leds: lm36274: fix use-after-free on unbind").

The only other in-tree driver that also registers under the MFD device
(drivers/regulator/lm363x-regulator.c) sets the parent to the MFD
device.

Set the parent of this LED to the MFD device, instead of the I2C client
device.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Tested-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

These settings are not parsed from DT and therefore semantically should
not be set in function with a name lm36274_parse_dt.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Tested-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

By using struct led_init_data when registering we do not need to parse
`label` DT property. Moreover `label` is deprecated and if it is not
present but `color` and `function` are, LED core will compose a name
from these properties instead.

Previously if the `label` DT property was not present, the code composed
name for the LED in the form
  "parent_name::"
For backwards compatibility we therefore set
  init_data->default_label = ":";
so that the LED will not get a different name if `label` property is not
present, nor are `color` and `function`.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Tested-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Do not use device_for_each_child_node. Since this driver works only with
once child node present, use device_get_next_child_node instead.
This also saves one level of indentation.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Rename this variable so that it is easier to read and easier to write in
80 columns. Also rename variable of this type in lm36274_brightness_set
from led to chip, to be consistent.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Tested-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Acer Iconia Tab A500 is an Android tablet device which has two LEDs
embedded into the Power Button. Orange LED indicates "battery charging"
status and white LED indicates "wake-up/charge-done" status. The new LED
driver provides control over both LEDs to userspace.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Simplify the return expression.
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

By using struct led_init_data when registering we do not need to parse
`label` DT property. Moreover `label` is deprecated and if it is not
present but `color` and `function` are, LED core will compose a name
from these properties instead.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

No need to use variable found, we can determine whether the mode was
found by comparing iterator variable to its limit.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Register each LED immediately after parsing OF properties. This
simplifies the driver.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Use helper variable dev instead of always writing &pdev->dev.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Return directly instead of setting result and breaking.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Rename variable led_dat to led in various functions.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Rename structures:
  ns2_led      -> ns2_led_of_one
  ns2_led_data -> ns2_led.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

This drivers leaks GPIO descriptors on driver removal. Use devres API
function devm_gpiod_get_from_of_node instead of gpiod_get_from_of_node
to avoid this.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Not-for-stable
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Move parsing of DT properties of one LED into separate function. This
saves indentation level and is nicer to read.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Move forward from platform data to device tree only.

Since commit c7896490 ("leds: ns2: Absorb platform data") the
platform data structure is absorbed into the driver, because nothing
else in the source tree uses it. Since nobody complained and all usage
of this driver is via device tree, change the code to work with device
tree only. As Linus Walleij wrote, the device tree should be the
preferred way forward anyway.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Since .remove method is not needed now that we use devres, there is no
need to remember the number of LEDs in struct ns2_led_priv. Alloc simple
array of ns2_led_data structs.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

By using devres version of LED registering function we can remove the
.remove method from this driver. The probe method also gets simpler.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

By using struct led_init_data when registering we do not need to parse
`label` DT property. Moreover `label` is deprecated and if it is not
present but `color` and `function` are, LED core will compose a name
from these properties instead.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: H. Nikolaus Schaller <hns@goldelico.com>
Cc: David Rivshin <drivshin@allworx.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

We can return the last ret value.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Use helper variable dev instead of always writing &pdev->dev.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

By using struct led_init_data when registering we do not need to parse
`label` DT property. Moreover `label` is deprecated and if it is not
present but `color` and `function` are, LED core will compose a name
from these properties instead.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Use helper variable dev instead of always writing &pdev->dev.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Sean Wang <sean.wang@mediatek.com>
Cc: John Crispin <john@phrozen.org>
Cc: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

By using struct led_init_data when registering we do not need to parse
`label` DT property. Moreover `label` is deprecated and if it is not
present but `color` and `function` are, LED core will compose a name
from these properties instead.

Since init_data is passed with fwnode handle, we do not need to set
the of_node member of the newly created LED classdev.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Sean Wang <sean.wang@mediatek.com>
Cc: John Crispin <john@phrozen.org>
Cc: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

By using struct led_init_data when registering we do not need to parse
`label` DT property. Moreover `label` is deprecated and if it is not
present but `color` and `function` are, LED core will compose a name
from these properties instead.

Previously if the `label` DT property was not present, the code composed
name for the LED in the form
  "max77650::"
For backwards compatibility we therefore set
  init_data->default_label = ":";
so that the LED will not get a different name if `label` property is not
present.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Use helper variable dev instead of always writing &client->dev, or
&priv->client->dev, or even &led->priv->client->dev.

With one more line moved reverse christmas tree is also achieved.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

By using struct led_init_data when registering we do not need to parse
`label` DT property. Moreover `label` is deprecated and if it is not
present but `color` and `function` are, LED core will compose a name
from these properties instead.

Previously if the `label` DT property was not present, the code composed
name for the LED in the form
  "parent_name::"
For backwards compatibility we therefore set
  init_data->default_label = ":";
so that the LED will not get a different name if `label` property is not
present.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

By using struct led_init_data when registering we do not need to parse
`label` DT property. Moreover `label` is deprecated and if it is not
present but `color` and `function` are, LED core will compose a name
from these properties instead.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Álvaro Fernández Rojas <noltari@gmail.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Jaedon Shin <jaedon.shin@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

These two drivers do not provide remove method and use devres for
allocation of other resources, yet they use led_classdev_register
instead of the devres variant, devm_led_classdev_register.

Fix this.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Álvaro Fernández Rojas <noltari@gmail.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Jaedon Shin <jaedon.shin@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Cc: stable@kernel.org

Fix OF node leaks by calling of_node_put in
for_each_available_child_of_node when the cycle breaks or returns.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Nikita Travkin <nikitos.tr@gmail.com>
Cc: Milo Kim <milo.kim@ti.com>
Cc: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Not-for-stable: untested, theoretical, insignificant leaks

Various drivers count and iterate over OF children nodes via
of_get_child_count and for_each_child_of_node. Instead they should use
of_get_available_child_count and for_each_available_child_of_node, so
that if a given node has the `status` property set to `disabled`, the
child will be ignored.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Andrey Utkin <andrey_utkin@fastmail.com>
Cc: Baolin Wang <baolin.wang7@gmail.com>
Cc: Baolin Wang <baolin.wang@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christian Mauderer <oss@c-mauderer.de>
Cc: Chunyan Zhang <zhang.lyra@gmail.com>
Cc: Dan Murphy <dmurphy@ti.com>
Cc: David Rivshin <drivshin@allworx.com>
Cc: Haojian Zhuang <haojian.zhuang@marvell.com>
Cc: H. Nikolaus Schaller <hns@goldelico.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Milo Kim <milo.kim@ti.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Nikita Travkin <nikitos.tr@gmail.com>
Cc: Orson Zhai <orsonzhai@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Philippe Retornaz <philippe.retornaz@epfl.ch>
Cc: Riku Voipio <riku.voipio@iki.fi>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Simon Shields <simon@lineageos.org>
Cc: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Cc: Xiaotong Lu <xiaotong.lu@spreadtrum.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

The devm_led_classdev_register_ext is given init_data with fwnode set,
so the LED core sets .of_node of the new LED classdev correctly.

Do not rewrite this value to parent of_node.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

The dev_of_node function should be preferred.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Orson Zhai <orsonzhai@gmail.com>
Cc: Baolin Wang <baolin.wang7@gmail.com>
Cc: Chunyan Zhang <zhang.lyra@gmail.com>
Cc: Sean Wang <sean.wang@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Simply use device_get_match_data instead of matching against the match
table again.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: H. Nikolaus Schaller <hns@goldelico.com>
Cc: David Rivshin <drivshin@allworx.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Christian Mauderer <oss@c-mauderer.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

This driver can be compiled on other platforms with small change if
COMPILE_TEST=y.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Dan Murphy <dmurphy@ti.com>
Cc: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

These drivers can be compiled without modification when COMPILE_TEST=y:
  cobalt-qube, cobalt-raq, netxbig, ns2 and s3c24xx
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

If LEDs are configured through device tree and the property 'label' is
omitted, the label is supposed to be generated from the properties
'function' and 'color' if present.  While this works fine for e.g. the
'leds-gpio' driver, it did not for 'leds-pwm'.

The reason is, you get this label naming magic only if you add a LED
device through 'devm_led_classdev_register_ext()' and pass a pointer to
the current device tree node.

For the following node from dts the LED appeared as 'led-5' in sysfs
before and as 'red:debug' after this change.

        pwm_leds {
                compatible = "pwm-leds";

                led-5 {
                        function = LED_FUNCTION_DEBUG;
                        color = <LED_COLOR_ID_RED>;
                        pwms = <&pwm0 2 10000000 0>;
                        max-brightness = <127>;

                        linux,default-trigger = "heartbeat";
                        panic-indicator;
                };
        };
Signed-off-by: Alexander Dahl <post@lespocky.de>
Cc: Marek Behún <marek.behun@nic.cz>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Common pattern of handling deferred probe can be simplified with
dev_err_probe().  Less code and also it prints the error value.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>