Extend the backlight event support to also allow the use of
poll()/select() on actual_brightness.
We already have the entire event hookup anyway, adding a single
function call in one line to get functionality like that is a really
good deal.
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
Certain hardware will send us events when the backlight brightness
changes. Add a function to update the value in the core, and
additionally send a uevent so that userspace can pop up appropriate
UI. The uevents are flagged depending on whether the update originated
in the kernel or from userspace, making it easier to only display UI
at the appropriate time.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
fb_notifier_call_chain() is called with info->lock held, i.e. in
do_fb_ioctl() => FBIOPUT_VSCREENINFO => fb_set_var() and the some
notifier callbacks, like fbcon_event_notify(), try to re-acquire
info->lock again.
Remove the lock/unlock_fb_info() in all the framebuffer notifier
callbacks' and be sure to always call fb_notifier_call_chain() with
info->lock held.
Reported-by: Pavel Roskin <proski@gnu.org>
Reported-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a circular locking dependency in the frame buffer console driver
pushing down the mutex fb_info->lock.
Circular locking dependecies occur calling the blocking
fb_notifier_call_chain() with fb_info->lock held. Notifier callbacks can
try to acquire mm->mmap_sem, while fb_mmap() acquires the locks in the
reverse order mm->mmap_sem => fb_info->lock.
Tested-by: Andrey Borzenkov <arvidjaar@mail.ru>
Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Check input properly in backlight, echo > brightness should not turn off
the backlight.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix printk warning]
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
Avoid driver callbacks when the brightness hasn't changed since
they're not necessary.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Convert the backlight and LCD classes from struct class_device
to struct device since class_device is scheduled for removal.
One nasty API break is the backlight power attribute has had to be
renamed to bl_power and the LCD power attribute has had to be renamed
to lcd_power since the original names clash with the core. I can't see
a way around this.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
sysfs is now completely out of driver/module lifetime game. After
deletion, a sysfs node doesn't access anything outside sysfs proper,
so there's no reason to hold onto the attribute owners. Note that
often the wrong modules were accounted for as owners leading to
accessing removed modules.
This patch kills now unnecessary attribute->owner. Note that with
this change, userland holding a sysfs node does not prevent the
backing module from being unloaded.
For more info regarding lifetime rule cleanup, please read the
following message.
http://article.gmane.org/gmane.linux.kernel/510293
(tweaked by Greg to not delete the field just yet, to make it easier to
merge things properly.)
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Per device data such as brightness belongs to the indivdual device
and should therefore be separate from the the backlight operation
function pointers. This patch splits the two types of data and
allows simplifcation of some code.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Move the setting/unsetting of pmac_backlight into the
backlight core instead of doing it in each driver.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
The backlight class wants notification whenever the console is blanked
but doesn't get this when hardware blanking fails and software blanking
is used. Changing FB_EVENT_BLANK to report both would be a behaviour
change which could confuse the console layer so add a new event for
software blanking and have the backlight class listen for both.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
backlight_device->sem has a very specific use as documented in the
header file. The external users of this are using it for a different
reason, to serialise access to the update_status() method.
backlight users were supposed to implement their own internal
serialisation of update_status() if needed but everyone is doing
things differently and incorrectly. Therefore add a global mutex to
take care of serialisation for everyone, once and for all.
Locking for get_brightness remains optional since most users don't
need it.
Also update the lcd class in a similar way.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Remove excessive numbers of (un)likely()s in the backlight core.
There are no hot paths in this code so rely on compiler to do
the right thing.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
This patch set adds generic abstract layer support for acpi video driver to
have generic user interface to control backlight and output switch control by
leveraging the existing backlight sysfs class driver, and by adding a new
video output sysfs class driver.
This patch:
Add dev argument for backlight_device_register to link the class device to
real device object. The platform specific driver should find a way to get the
real device object for their video device.
[akpm@osdl.org: build fix]
[akpm@osdl.org: fix msi-laptop.c]
Signed-off-by: Luming Yu <Luming.yu@intel.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
ACPI drivers like ibm-acpi are moving to the backlight sysfs
infrastructure. During ibm-acpi testing, I have noticed that
backlight_device_unregister() sets the display brightness and power to
zero.
This causes the display to be dimmed on ibm-acpi module removal. It will
affect all other ACPI drivers that are being converted to use the backlight
class, as well. It also affects a number of framebuffer devices that are
used on desktops and laptops which might also not want such behaviour.
Since working around this behaviour requires undesireable hacks, Richard
Purdie decided that we would be better off reverting the changes in the
sysfs class, and adding the code to dim and power off the backlight device
to the drivers that want it. This patch is my attempt to do so.
Patch against latest linux-2.6.git. Changes untested, as I lack the
required hardware. Still, they are trivial enough that, apart from typos,
there is little chance of getting them wrong.
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The backlight layer should be independent from the framebuffer layer. It
can use the services offered by the framebuffer, but its absence should not
prevent the backlight/lcd layer from functioning.
[akpm@osdl.org: cleanups]
Signed-off-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
