The reset command is part of the init sequence and it take effect
only if the lcd is powered.
The effect of the bug was that the sequence:
set lcd power_state to FB_BLANK_POWERDOWN
set lcd power_state to FB_BLANK_UNBLANK
Did not produced a complete reboot of the LCD which was showing fuzzy
colours.
This was not experienced before implementing correctly all the LCD power
states with the patch [1]. Since before the patch [1] the regulators were
not touched and the LCD shutdown was reached with a register write. After
the patch [1] a complete boot sequence with an initial reset is needed for
the display every time the LCD is powered up.
drivers-video-backlight-l4f00242t03c-full-implement-fb-power-states-for-this-lcd.patch
Signed-off-by: Alberto Panizzo <maramaopercheseimorto@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
According to the comment describing ops_lock in the definition of struct
backlight_device and when comparing with other functions in backlight.c
the mutex must be hold when checking ops to be non-NULL.
Fixes a problem added by c835ee7f41 ("backlight: Add suspend/resume
support to the backlight core") in Jan 2009.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This affects the get/set of the current Ambient Light Zone. Reading
should return an integer between 1..3 (1 = Daylight, 2 = office, 3 =
dark). Writing a value between 1..3 forces the backlight controller to
enter the corresponding Ambient Light Zone. Writing 0 returns to normal
operation.
Fix valid range checking so we don't write invalid values to the
controller, and make sure we subtract 1, since this is what the register
definition (CFGR:BLV) requires. Otherwise the values written don't work
correctly.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The intensity of the backlight can be varied from a range of
max_brightness to zero. Though most, if not all the pwm based backlight
devices start flickering at lower brightness value. And also for each
device there exists a brightness value below which the backlight appears
to be turned off though the value is not equal to zero.
If the range of brightness for a device is from zero to max_brightness. A
graph is plotted for brightness Vs intensity for the pwm based backlight
device has to be a linear graph.
intensity
| /
| /
| /
|/
---------
0 max_brightness
But pratically on measuring the above we note that the intensity of
backlight goes to zero(OFF) when the value in not zero almost nearing to
zero(some x%). so the graph looks like
intensity
| /
| /
| /
| |
------------
0 x max_brightness
In order to overcome this drawback knowing this x% i.e nothing but the low
threshold beyond which the backlight is off and will have no effect, the
brightness value is being offset by the low threshold value(retaining the
linearity of the graph). Now the graph becomes
intensity
| /
| /
| /
| /
-------------
0 max_brightness
With this for each and every digit increment in the brightness from zero
there is a change in the intensity of backlight. Devices having this
behaviour can set the low threshold brightness(lth_brightness) and pass
the same as platform data else can have it as zero.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Arun Murthy <arun.murthy@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I2C drivers can use the clientdata-pointer to point to private data. As I2C
devices are not really unregistered, but merely detached from their driver, it
used to be the drivers obligation to clear this pointer during remove() or a
failed probe(). As a couple of drivers forgot to do this, it was agreed that it
was cleaner if the i2c-core does this clearance when appropriate, as there is
no guarantee for the lifetime of the clientdata-pointer after remove() anyhow.
This feature was added to the core with commit
e4a7b9b04d to fix the faulty drivers.
As there is no need anymore to clear the clientdata-pointer, remove all current
occurrences in the drivers to simplify the code and prevent confusion.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This patch properly unregisters a previously registered backlight device object
in error handling
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
Properly unregister a previously registered backlight device object in error
handling of max8925_backlight_probe.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
Error handling fixes:
1. In the case of kzalloc failure, simple return -ENOMEM instead of goto
err. ( priv is NULL in this case )
2. In the case of gpio_request fail for reset_gpio and data_enable_gpio,
properly release resources by goto err and err2 respectively.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Alberto Panizzo <maramaopercheseimorto@gmail.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
This is S6E63M0 AMOLED LCD Panel(480x800) driver using 3-wired SPI
interface also almost features for lcd panel driver has been implemented
in here. and I added new structure common for all the lcd panel drivers
to include/linux/lcd.h file.
LCD Panel driver needs interfaces for controlling device power such as
power on/off and reset. these interfaces are device specific so it should
be implemented to machine code at this time, we should create new
structure for registering these functions as callbacks and also a header
file for that structure and finally registered callback functions would be
called by lcd panel driver. such header file(including new structure for
lcd panel) would be added for all the lcd panel drivers.
If anyone provides common structure for registering such callback
functions then we could reduce unnecessary header files for lcd panel. I
thought that suitable anyone could be include/linux/lcd.h so a new
lcd_platform_data structure was added there.
[akpm@linux-foundation.org: coding-style fixes]
[randy.dunlap@oracle.com: fix s6e63m0 kconfig]
[randy.dunlap@oracle.com: fix device attribute functions return types]
Signed-off-by: InKi Dae <inki.dae@samsung.com>
Reviewed-by: KyungMin Park <kyungmin.park.samsung.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
Fix DMI_SYS_VENDOR for MacBook1,1.
When the MacBook1,1 came out Apple was still named Apple Computer, I am
not sure if this applies to older MacBook2,1 versions aswell.
Signed-off-by: Steffen Röcker <sroecker@gmail.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
The EP9307, EP9312, and EP9315 processors include a framebuffer
peripheral. This peripheral has a dedicated pwm output called
BRIGHT that can be used to control the backlight on an LCD.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>