Commit Graph

849 Commits

Author SHA1 Message Date
Linus Walleij
ee0c8e494c backlight: corgi: Convert to use GPIO descriptors
The code in the Corgi backlight driver can be considerably
simplified by moving to GPIO descriptors and lookup tables
from the board files instead of passing GPIO numbers using
the old API.

Make sure to encode inversion semantics for the Akita and
Spitz platforms inside the GPIO lookup table and drop the
custom inversion semantics from the driver.

All in-tree users are converted in this patch.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-03-25 09:30:46 +00:00
Linus Walleij
2644f912b4 backlight: pwm_bl: Switch to full GPIO descriptor
The PWM backlight still supports passing a enable GPIO line as
platform data using the legacy <linux/gpio.h> API.

It turns out that ever board using this mechanism except one
is pass .enable_gpio = -1. So we drop all these cargo-culted -1's
from all instances of this platform data in the kernel.

The remaning board, Palm TC, is converted to pass a machine
descriptior table with the "enable" GPIO instead, and delete the
platform data entry for enable_gpio and the code handling it
and things should work smoothly with the new API.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org
Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-03-18 15:05:57 +00:00
Chen Zhou
7af43a7669 backlight: qcom-wled: Fix unsigned comparison to zero
Fixes coccicheck warning:
./drivers/video/backlight/qcom-wled.c:1104:5-15:
	WARNING: Unsigned expression compared with zero: string_len > 0

The unsigned variable string_len is assigned a return value from the call
to of_property_count_elems_of_size(), which may return negative error code.

Fixes: 775d2ffb4a ("backlight: qcom-wled: Restructure the driver for WLED3")
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Kiran Gunda <kgunda@codeaurora.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-01-23 07:53:12 +00:00
Linus Walleij
c8fdcc8672 backlight: bd6107: Convert to use GPIO descriptor
The Rohm BD6107 driver can pass a fixed GPIO line using the old
GPIO API using platform data. As there are no in-tree users of this
platform data since 2013, we can convert this to use a GPIO descriptor
and require any out-of-tree consumers to pass the GPIO using
a machine descriptor table instead.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-12-16 10:32:27 +00:00
Linus Walleij
edeec4fdc7 backlight: ams369fg06: Drop GPIO include
The driver includes <linux/gpio.h> yet fails to use symbols
from any the header so drop the include.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-12-16 10:30:41 +00:00
Colin Ian King
102a1b3821 backlight: qcom-wled: Fix spelling mistake "trigged" -> "triggered"
There is a spelling mistake in a dev_err error message. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-13 11:31:52 +00:00
Bartosz Golaszewski
9afa302473 backlight: gpio: Pull gpio_backlight_initial_power_state() into probe
The probe function in the gpio-backlight driver is quite short. If we
pull gpio_backlight_initial_power_state() into probe we can drop two
more fields from struct gpio_backlight and shrink the driver code.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-11 11:34:01 +00:00
Bartosz Golaszewski
d17465a0af backlight: gpio: Use a helper variable for &pdev->dev
Instead of dereferencing pdev each time, use a helper variable for
the associated device pointer.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-11 11:34:01 +00:00
Bartosz Golaszewski
f35f06b784 backlight: gpio: Simplify the platform data handling
Now that the last user of platform data (sh ecovec24) defines a proper
GPIO lookup and sets the 'default-on' device property, we can drop the
platform_data-specific GPIO handling and unify a big chunk of code.

The only field used from the platform data is now the fbdev pointer.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-11 11:34:01 +00:00
Bartosz Golaszewski
706dc68102 backlight: gpio: Explicitly set the direction of the GPIO
The GPIO backlight driver currently requests the line 'as is', without
acively setting its direction. This can lead to problems: if the line
is in input mode by default, we won't be able to drive it later when
updating the status and also reading its initial value doesn't make
sense for backlight setting.

Request the line 'as is' initially, so that we can read its value
without affecting it but then change the direction to output explicitly
when setting the initial brightness.

Also: check the current direction and only read the value if it's output.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-11 11:34:01 +00:00
Bartosz Golaszewski
3cfc291bfe backlight: gpio: Remove stray newline
Remove a double newline from the driver.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-11 11:34:01 +00:00
Bartosz Golaszewski
8a05548375 backlight: gpio: Remove unneeded include
We no longer use any symbols from of_gpio.h. Remove this include.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-11 11:33:57 +00:00
Arnd Bergmann
0b0cb52bd8 video: backlight: tosa: Use GPIO lookup table
The driver should not require a machine specific header. Change
it to pass the GPIO line through a lookup table, and move the
timing generator definitions into the drivers itself.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-11 09:29:56 +00:00
Kiran Gunda
8663c188be backlight: qcom-wled: Add auto string detection logic
The auto string detection algorithm checks if the current WLED
sink configuration is valid. It tries enabling every sink and
checks if the OVP fault is observed. Based on this information
it detects and enables the valid sink configuration.
Auto calibration will be triggered when the OVP fault interrupts
are seen frequently thereby it tries to fix the sink configuration.

The auto-detection also kicks in when the connected LED string
of the display-backlight malfunctions (because of damage) and
requires the damaged string to be turned off to prevent the
complete panel and/or board from being damaged.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-01 08:11:39 +00:00
Kiran Gunda
feeab87b30 backlight: qcom-wled: Add support for short circuit handling
Handle the short circuit interrupt and check if the short circuit
interrupt is valid. Re-enable the module to check if it goes
away. Disable the module altogether if the short circuit event
persists.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-01 08:11:39 +00:00
Kiran Gunda
03b2b5e869 backlight: qcom-wled: Add support for WLED4 peripheral
WLED4 peripheral is present on some PMICs like pmi8998 and
pm660l. It has a different register map and configurations
are also different. Add support for it.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-01 08:11:50 +00:00
Kiran Gunda
775d2ffb4a backlight: qcom-wled: Restructure the driver for WLED3
Restructure the driver to add the support for new WLED
peripherals.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-01 08:11:47 +00:00
Kiran Gunda
bb800a3715 backlight: qcom-wled: Rename PM8941* to WLED3
Rename the PM8941* references as WLED3 to make the driver
generic and have WLED support for other PMICs. Also rename
"i_boost_limit" and "i_limit" variables to "boost_i_limit"
and "string_i_limit" respectively to resemble the corresponding
register names.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-01 08:11:39 +00:00
Kiran Gunda
51c0ddc758 backlight: qcom-wled: Rename pm8941-wled.c to qcom-wled.c
pm8941-wled.c driver is supporting the WLED peripheral
on pm8941. Rename it to qcom-wled.c so that it can support
WLED on multiple PMICs.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-01 08:03:29 +00:00
Thomas Gleixner
53e4929150 backlight: Kconfig: jornada720: Use CONFIG_PREEMPTION
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.

Switch the Kconfig dependency to CONFIG_PREEMPTION.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[Sebastian: +LCD_HP700]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-10-18 08:38:48 +01:00
Rasmus Villemoes
ca58b37034 backlight: pwm_bl: Switch to power-of-2 base for fixed-point math
Using a power-of-2 instead of power-of-10 base makes the computations
much cheaper. 2^16 is safe; retval never becomes more than 2^48 +
2^32/2. On a 32 bit platform, the very expensive 64/32 division at the
end of cie1931() instead becomes essentially free (a shift by 32 is
just a register rename).

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-10-14 08:57:45 +01:00
Rasmus Villemoes
407feae1ca backlight: pwm_bl: Drop use of int_pow()
For a fixed small exponent of 3, it is more efficient to simply use
two explicit multiplications rather than calling the int_pow() library
function: Aside from the function call overhead, its implementation
using repeated squaring means it ends up doing four 64x64
multiplications.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-10-14 08:57:45 +01:00
Rasmus Villemoes
e802cbafcb backlight: pwm_bl: Eliminate a 64/32 division
lightness*1000 is nowhere near overflowing 32 bits, so we can just use
an ordinary 32/32 division, which is much cheaper than the 64/32 done
via do_div().

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-10-14 08:57:45 +01:00
Rasmus Villemoes
efdf690e15 backlight: pwm_bl: Fix cie1913 comments and constant
The "break-even" point for the two formulas is L==8, which is also
what the code actually implements. [Incidentally, at that point one
has Y=0.008856, not 0.08856].

Moreover, all the sources I can find say the linear factor is 903.3
rather than 902.3, which makes sense since then the formulas agree at
L==8, both yielding the 0.008856 figure to four significant digits.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-10-14 08:57:45 +01:00
Matthias Kaehlcke
349ee12287 backlight: pwm_bl: Add missing curly branches in else branch
Add curly braces to an 'else' branch in pwm_backlight_update_status()
to match the corresponding 'if' branch.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-10-14 08:57:45 +01:00
Matthias Kaehlcke
de6f2a7fa2 backlight: pwm_bl: Don't assign levels table repeatedly
pwm_backlight_probe() re-assigns pb->levels for every brightness
level. This is not needed and was likely not intended, since
neither side of the assignment changes during the loop. Assign
the field only once.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-10-14 08:57:45 +01:00
Andreas Kemnade
0e0e78e32e backlight: lm3630a: Add an enable gpio for the HWEN pin
For now just enable it in the probe function to allow I2C
access. Disabling also means resetting the register values
to default and according to the datasheet does not give
power savings.

Tested on Kobo Clara HD.

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-10-02 14:25:27 +01:00
Nishka Dasgupta
7050a7c374 backlight: ipaq_micro: Make structure micro_bl_props constant
Static structure micro_bl_props, having type backlight_properties, is
used only once, when it is passed as the last argument to function
devm_backlight_device_register(). devm_backlight_device_register() is
defined with its last parameter being declared constant. Hence make
micro_bl_props itself constant as well.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-10-02 14:19:00 +01:00
Andreas Kemnade
8ad003e734 backlight: lm3630a: Fix module aliases
Devicetree aliases are missing, so that module autoloading
does not work properly.

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-10-02 14:12:15 +01:00
Linus Torvalds
d0b3cfee33 - Core Frameworks
- Obtain scale type through sysfs
 
  - New Functionality
    - Provide Device Tree functionality; rave-sp-backlight
    - Calculate if scale type is (non-)linear; pwm_bl
 
  - Fix-ups
    - Simplify code; lm3630a_bl
    - Trivial rename/whitespace/typo fixes; lms283gf05
    - Remove superfluous NULL check; tosa_lcd
    - Fix power state initialisation; gpio_backlight
    - List supported file; MAINTAINERS
 
  - Bug Fixes
    - Kconfig - default to not building unless requested; {LED,BACKLIGHT}_CLASS_DEVICE
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Merge tag 'backlight-next-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight

Pull backlight updates from Lee Jones:
 "Core Frameworks
   - Obtain scale type through sysfs

  New Functionality:
   - Provide Device Tree functionality in rave-sp-backlight
   - Calculate if scale type is (non-)linear in pwm_bl

  Fix-ups:
   - Simplify code in lm3630a_bl
   - Trivial rename/whitespace/typo fixes in lms283gf05
   - Remove superfluous NULL check in tosa_lcd
   - Fix power state initialisation in gpio_backlight
   - List supported file in MAINTAINERS

  Bug Fixes:
   - Kconfig - default to not building unless requested in
     {LED,BACKLIGHT}_CLASS_DEVICE"

* tag 'backlight-next-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: pwm_bl: Set scale type for brightness curves specified in the DT
  backlight: pwm_bl: Set scale type for CIE 1931 curves
  backlight: Expose brightness curve type through sysfs
  MAINTAINERS: Add entry for stable backlight sysfs ABI documentation
  backlight: gpio-backlight: Correct initial power state handling
  video: backlight: tosa_lcd: drop check because i2c_unregister_device() is NULL safe
  video: backlight: Drop default m for {LCD,BACKLIGHT_CLASS_DEVICE}
  backlight: lms283gf05: Fix a typo in the description passed to 'devm_gpio_request_one()'
  backlight: lm3630a: Switch to use fwnode_property_count_uXX()
  backlight: rave-sp: Leave initial state and register with correct device
2019-09-23 19:33:56 -07:00
Matthias Kaehlcke
c0b64faf0f backlight: pwm_bl: Set scale type for brightness curves specified in the DT
Check if a brightness curve specified in the device tree is linear or
not and set the corresponding property accordingly. This makes the
scale type available to userspace via the 'scale' sysfs attribute.

To determine if a curve is linear it is compared to a interpolated linear
curve between min and max brightness. The curve is considered linear if
no value deviates more than +/-5% of ${brightness_range} from their
interpolated value.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 15:55:15 +01:00
Matthias Kaehlcke
511a204638 backlight: pwm_bl: Set scale type for CIE 1931 curves
For backlight curves calculated with the CIE 1931 algorithm set
the brightness scale type to non-linear. This makes the scale type
available to userspace via the 'scale' sysfs attribute.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 15:55:11 +01:00
Matthias Kaehlcke
d55c028f8b backlight: Expose brightness curve type through sysfs
Backlight brightness curves can have different shapes. The two main
types are linear and non-linear curves. The human eye doesn't
perceive linearly increasing/decreasing brightness as linear (see
also 88ba95bedb "backlight: pwm_bl: Compute brightness of LED
linearly to human eye"), hence many backlights use non-linear (often
logarithmic) brightness curves. The type of curve currently is opaque
to userspace, so userspace often uses more or less reliable heuristics
(like the number of brightness levels) to decide whether to treat a
backlight device as linear or non-linear.

Export the type of the brightness curve via the new sysfs attribute
'scale'. The value of the attribute can be 'linear', 'non-linear' or
'unknown'. For devices that don't provide information about the scale
of their brightness curve the value of the 'scale' attribute is 'unknown'.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 15:55:03 +01:00
Peter Ujfalusi
ec665b756e backlight: gpio-backlight: Correct initial power state handling
The default-on property - or the def_value via legacy pdata) should be
handled as:
if it is 1, the backlight must be enabled (kept enabled)
if it is 0, the backlight must be disabled (kept disabled)

This only works for the case when default-on is set. If it is not set then
the brightness of the backlight is set to 0. Now if the backlight is
enabled by external driver (graphics) the backlight will stay disabled since
the brightness is configured as 0. The backlight will not turn on.

In order to minimize screen flickering during device boot:

The initial brightness should be set to 1.

If booted in non DT mode or no phandle link to the backlight node:
follow the def_value/default-on to select UNBLANK or POWERDOWN

If in DT boot we have phandle link then leave the GPIO in a state which the
bootloader left it and let the user of the backlight to configure it
further.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 15:54:52 +01:00
Wolfram Sang
28a1d72a22 video: backlight: tosa_lcd: drop check because i2c_unregister_device() is NULL safe
No need to check the argument of i2c_unregister_device() because the
function itself does it.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 15:54:47 +01:00
Geert Uytterhoeven
bcd69da98e video: backlight: Drop default m for {LCD,BACKLIGHT_CLASS_DEVICE}
When running "make oldconfig" on a .config where
CONFIG_BACKLIGHT_LCD_SUPPORT is not set, two new config options
("Lowlevel LCD controls" and "Lowlevel Backlight controls") appear, both
defaulting to "m".

Drop the "default m", as options should default to disabled, and because
several driver config options already select LCD_CLASS_DEVICE or
BACKLIGHT_CLASS_DEVICE when needed.

Fixes: 8c5dc8d9f1 ("video: backlight: Remove useless BACKLIGHT_LCD_SUPPORT kernel symbol")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 15:54:29 +01:00
Christophe JAILLET
30f644fd6e backlight: lms283gf05: Fix a typo in the description passed to 'devm_gpio_request_one()'
The description passed to 'devm_gpio_request_one()' should be related to
LMS283GF05, not LMS285GF05.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-08-12 09:11:22 +01:00
Andy Shevchenko
072e2c8192 backlight: lm3630a: Switch to use fwnode_property_count_uXX()
Use use fwnode_property_count_uXX() directly, that makes code neater.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-08-12 09:11:16 +01:00
Lucas Stach
865cac14c2 backlight: rave-sp: Leave initial state and register with correct device
This way the backlight can be referenced through its device node and
enabling/disabling can be managed through the panel driver.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-08-12 09:11:10 +01:00
Sam Ravnborg
e7642f3585 backlight: drop EARLY_EVENT_BLANK support
There was no users left - so drop the code to support EARLY_EVENT_BLANK.
This patch removes the support in backlight,
and drop the notifier in fbmem.

That EARLY_EVENT_BLANK is not used can be verified that no driver set any of:

    lcd_ops.early_set_power()
    lcd_ops.r_early_set_power()

Noticed while browsing backlight code for other reasons.

v2:
- Fix changelog to say "EARLY_EVENT_BLANK" (Daniel)

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Peter Rosin <peda@axentia.se>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-fbdev@vger.kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190725143224.GB31803@ravnborg.org
2019-08-05 21:52:53 +02:00
Linus Torvalds
5095062641 - New Functionality
- Provide support for ACPI enumeration; gpio_backlight
 
  - Fix-ups
    - SPDX fixups; pwm_bl
    - Fix linear	brightness levels to include number available; pwm_bl
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Merge tag 'backlight-next-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight

Pull backlight updates from Lee Jones:
 "New Functionality:
   - Provide support for ACPI enumeration; gpio_backlight

  Fix-ups:
   - SPDX fixups; pwm_bl
   - Fix linear	brightness levels to include number available; pwm_bl"

* tag 'backlight-next-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: pwm_bl: Fix heuristic to determine number of brightness levels
  backlight: gpio_backlight: Enable ACPI enumeration
  backlight: pwm_bl: Convert to use SPDX identifier
2019-07-16 09:25:04 -07:00
Linus Torvalds
2d41ef5432 fbdev changes for v5.3:
- remove fbdev notifier usage for fbcon (as prep work to clean up the fbcon
   locking), add locking checks in vt/console code and make assorted cleanups
   in fbdev and backlight code (Daniel Vetter)
 
 - add COMPILE_TEST support to atmel_lcdfb, da8xx-fb, gbefb, imxfb, pvr2fb and
   pxa168fb drivers (me)
 
 - fix DMA API abuse in au1200fb and jz4740_fb drivers (Christoph Hellwig)
 
 - add check for new BGRT status field rotation bits in efifb driver (Hans de
   Goede)
 
 - mark expected switch fall-throughs in s3c-fb driver (Gustavo A. R. Silva)
 
 - remove fbdev mxsfb driver in favour of the drm version (Fabio Estevam)
 
 - remove broken rfbi code from omap2fb driver (me)
 
 - misc fixes (Arnd Bergmann, Shobhit Kukreti, Wei Yongjun, me)
 
 - misc cleanups (Gustavo A. R. Silva, Colin Ian King, me)
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Merge tag 'fbdev-v5.3' of git://github.com/bzolnier/linux

Pull fbdev updates from Bartlomiej Zolnierkiewicz:

 - remove fbdev notifier usage for fbcon (as prep work to clean up the
   fbcon locking), add locking checks in vt/console code and make
   assorted cleanups in fbdev and backlight code (Daniel Vetter)

 - add COMPILE_TEST support to atmel_lcdfb, da8xx-fb, gbefb, imxfb,
   pvr2fb and pxa168fb drivers (me)

 - fix DMA API abuse in au1200fb and jz4740_fb drivers (Christoph
   Hellwig)

 - add check for new BGRT status field rotation bits in efifb driver
   (Hans de Goede)

 - mark expected switch fall-throughs in s3c-fb driver (Gustavo A. R.
   Silva)

 - remove fbdev mxsfb driver in favour of the drm version (Fabio
   Estevam)

 - remove broken rfbi code from omap2fb driver (me)

 - misc fixes (Arnd Bergmann, Shobhit Kukreti, Wei Yongjun, me)

 - misc cleanups (Gustavo A. R. Silva, Colin Ian King, me)

* tag 'fbdev-v5.3' of git://github.com/bzolnier/linux: (62 commits)
  video: fbdev: imxfb: fix a typo in imxfb_probe()
  video: fbdev: s3c-fb: Mark expected switch fall-throughs
  video: fbdev: s3c-fb: fix sparse warnings about using incorrect types
  video: fbdev: don't print error message on framebuffer_alloc() failure
  video: fbdev: intelfb: return -ENOMEM on framebuffer_alloc() failure
  video: fbdev: s3c-fb: return -ENOMEM on framebuffer_alloc() failure
  vga_switcheroo: Depend upon fbcon being built-in, if enabled
  video: fbdev: omap2: remove rfbi
  video: fbdev: atmel_lcdfb: remove redundant initialization to variable ret
  video: fbdev-MMP: Use struct_size() in devm_kzalloc()
  video: fbdev: controlfb: fix warnings about comparing pointer to 0
  efifb: BGRT: Add check for new BGRT status field rotation bits
  jz4740_fb: fix DMA API abuse
  video: fbdev: pvr2fb: fix link error for pvr2fb_pci_exit
  video: fbdev: s3c-fb: add COMPILE_TEST support
  video: fbdev: imxfb: fix sparse warnings about using incorrect types
  video: fbdev: pvr2fb: fix build warning when compiling as module
  fbcon: Export fbcon_update_vcs
  backlight: simplify lcd notifier
  staging/olpc_dcon: Add drm conversion to TODO
  ...
2019-07-09 09:55:45 -07:00
Matthias Kaehlcke
73fbfc4994 backlight: pwm_bl: Fix heuristic to determine number of brightness levels
With commit 88ba95bedb ("backlight: pwm_bl: Compute brightness of
LED linearly to human eye") the number of set bits (aka hweight())
in the PWM period is used in the heuristic to determine the number
of brightness levels, when the brightness table isn't specified in
the DT. The number of set bits doesn't provide a reliable clue about
the length of the period, instead change the heuristic to:

 nlevels = period / fls(period)

Also limit the maximum number of brightness levels to 4096 to avoid
excessively large tables.

With this the number of levels increases monotonically with the PWM
period, until the maximum of 4096 levels is reached:

period (ns)    # levels

100    	       16
500	       62
1000	       111
5000	       416
10000	       769
50000	       3333
100000	       4096

Fixes: 88ba95bedb ("backlight: pwm_bl: Compute brightness of LED linearly to human eye")
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-06-27 07:09:05 +01:00
Andy Shevchenko
98b7404eb7 backlight: gpio_backlight: Enable ACPI enumeration
ACPI allows to enumerate specific devices by using compatible strings.
Enable that enumeration for GPIO based backlight devices.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-06-27 07:09:05 +01:00
Andy Shevchenko
5076fbed57 backlight: pwm_bl: Convert to use SPDX identifier
Reduce size of duplicated comments by switching to use SPDX identifier.

No functional change.

While here, correct MODULE_LICENSE() string to be aligned with license text.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-06-27 07:09:05 +01:00
Thomas Gleixner
d2912cb15b 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>
2019-06-19 17:09:55 +02:00
Thomas Gleixner
caab277b1d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234
Based on 1 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
  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 you should have received a copy of the gnu general
  public license along with this program if not see http www gnu org
  licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 503 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>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:07 +02:00
Daniel Vetter
1dcff4ae65 backlight: simplify lcd notifier
With all the work I've done on replacing fb notifier calls with direct
calls into fbcon the backlight/lcd notifier is the only user left.

It will only receive events now that it cares about, hence we can
remove this check.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jingoo Han <jingoohan1@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-34-daniel.vetter@ffwll.ch
2019-06-13 10:07:20 +02:00
Daniel Vetter
9e14670026 fbcon: replace FB_EVENT_MODE_CHANGE/_ALL with direct calls
Create a new wrapper function for this, feels like there's some
refactoring room here between the two modes.

v2: backlight notifier is also interested in the mode change event,
it calls lcd->set_mode, of which there are 3 implementations. Thanks
to Maarten for spotting this. So we keep that. We can ditch the differentiation
between mode change and all mode changes (because backlight notifier
doesn't care), and we can drop the FBINFO_MISC_USEREVENT stuff too,
because that's just to prevent recursion between fbmem.c and fbcon.c.

While at it flatten the control flow a bit.

v3: Need to add a static inline to the dummy function.

v4: Add missing #include <fbcon.h> to sh_mob (Sam).

Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Yisheng Xie <ysxie@foxmail.com>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Peter Rosin <peda@axentia.se>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: linux-fbdev@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-29-daniel.vetter@ffwll.ch
2019-06-12 20:30:21 +02:00
Daniel Vetter
7a625549ea Revert "backlight/fbcon: Add FB_EVENT_CONBLANK"
This reverts commit 994efacdf9.

The justification is that if hw blanking fails (i.e. fbops->fb_blank)
fails, then we still want to shut down the backlight. Which is exactly
_not_ what fb_blank() does and so rather inconsistent if we end up
with different behaviour between fbcon and direct fbdev usage. Given
that the entire notifier maze is getting in the way anyway I figured
it's simplest to revert this not well justified commit.

v2: Add static inline to the dummy version.

Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Yisheng Xie <ysxie@foxmail.com>
Cc: linux-fbdev@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-25-daniel.vetter@ffwll.ch
2019-06-12 20:29:40 +02:00