Convert drivers/video/backlight/class to use dev_pm_ops for power
management and remove Legacy PM ops hooks.

With this change, backlight class registers suspend/resume callbacks via
class->pm (dev_pm_ops) instead of Legacy class->suspend/resume.  When
__device_suspend() runs call-backs, it will find class->pm ops for the
backlight class.

[jg1.han@samsung.com: add CONFIG_PM_SLEEP to suspend/resume functions]
Signed-off-by: NShuah Khan <shuah.kh@samsung.com>
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Cc: Shuah Khan <shuahkhan@gmail.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Cc: Shuah Khan <shuahkhan@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

These functions allow the driver core to automatically clean up any
allocation made by backlight drivers.  Thus it simplifies the error
paths.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Calling dev_set_name with a single paramter causes it to be handled as a
format string.  Many callers are passing potentially dynamic string
content, so use "%s" in those cases to avoid any potential accidents,
including wrappers like device_create*() and bdi_register().
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Michał's previous patch missed this backlight check to fix up the
class_find_device() arguments.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Cc: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This function finds the struct backlight_device for a given device tree
node.  A dummy function is provided so that it safely compiles out if OF
support is disabled.

[akpm@linux-foundation.org: Don't use IS_ENABLED(CONFIG_OF)]
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>
Acked-by: NJingoo Han <jg1.han@samsung.com>
Reviewed-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Thierry Reding <thierry.reding@avionic-design.de>
Reviewed-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use pr_warn() and pr_debug() instead of printk to allow dynamic debugging.
The pr_fmt prefix for pr_ macros is used.  Also fix checkpatch warnings
as below:

WARNING: Prefer pr_warn(... to printk(KERN_WARNING, ...

[akpm@linux-foundation.org: use KBUILD_MODNAME, per Joe]
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The usage of simple_strtoul() or strict_strtoul() is not preferred.  Thus,
kstrtoul should be used.

This patch also fixes checkpatch error as follows:
ERROR: space required after that ',' (ctx:VxV)
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since backlight_types[] isn't modified, let's declare it const.  That
was probably the intention of the author of commit bb7ca747
("backlight: add backlight type"), via which the "const char const *"
construct was introduced.  The duplicate const was detected by sparse.
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There may be multiple ways of controlling the backlight on a given
machine.  Allow drivers to expose the type of interface they are
providing, making it possible for userspace to make appropriate policy
decisions.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Airlie <airlied@linux.ie>
Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus 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 c835ee7f ("backlight: Add suspend/resume
support to the backlight core") in Jan 2009.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: NRichard Purdie <rpurdie@linux.intel.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

Values such as max_brightness should be set before backlights are
registered, but the current API doesn't allow that. Add a parameter to
backlight_device_register and update drivers to ensure that they
set this correctly.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

check_fb from backlight_ops lacks a reference to the backlight_device
that's being referred to. Add this parameter so a backlight_device
can be mapped to a single framebuffer, especially if the same driver
handles multiple devices on a single system.
Signed-off-by: NBruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

Signed-off-by: NEmese Revfy <re.emese@gmail.com>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

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: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NRichard 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: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NRichard 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: NPavel Roskin <proski@gnu.org>
Reported-by: NEric Miao <eric.y.miao@gmail.com>
Signed-off-by: NAndrea 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: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus 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: NAndrey Borzenkov <arvidjaar@mail.ru>
Signed-off-by: NAndrea 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: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add suspend/resume support to the backlight core and enable use of it
by appropriate drivers.
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

Always invoke backlight_update_status when users want to change
the backlight.

For setups where brightness change is an expensive operation,
this could be done in the driver rather than the core.

http://bugzilla.kernel.org/show_bug.cgi?id=12249Signed-off-by: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

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: NPavel Machek <pavel@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NSebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>

Avoid driver callbacks when the brightness hasn't changed since
they're not necessary.
Signed-off-by: NHelge Deller <deller@gmx.de>
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>

This patch makes two needlessly global structs static.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NRichard 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: NRichard Purdie <rpurdie@rpsys.net>
Acked-by: NGreg 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: NTejun Heo <htejun@gmail.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg 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: NRichard 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: NRichard 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: NRichard Purdie <rpurdie@rpsys.net>

Convert internal semaphore to a mutex
Signed-off-by: NRichard 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: NRichard 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: NDmitry Torokhov <dtor@mail.ru>
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>

Fix error handling when registering new device
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
Signed-off-by: NRichard 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: NLuming Yu <Luming.yu@intel.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLen 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: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: NRichard Purdie <rpurdie@rpsys.net>
Acked-by: NPavel Machek <pavel@ucw.cz>
Acked-by: NJames Simmons <jsimmons@infradead.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus 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: NJames Simmons <jsimmons@infradead.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

- move some structs and arrays to the read-only (.rodata) section

[akpm@osdl.org: build fix]
Signed-off-by: NHelge Deller <deller@gmx.de>
Acked-by: NJames Simmons <jsimmons@infradead.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The backlight and LCD class _store functions currently accept values like "34
some random strings" without error.  This corrects them to return -EINVAL if
the value is not numeric with an optional byte of trailing whitespace.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Backlight class attributes are currently easy to implement incorrectly.
Moving certain handling into the backlight core prevents this whilst at the
same time makes the drivers simpler and consistent.  The following changes are
included:

The brightness attribute only sets and reads the brightness variable in the
backlight_properties structure.

The power attribute only sets and reads the power variable in the
backlight_properties structure.

Any framebuffer blanking events change a variable fb_blank in the
backlight_properties structure.

The backlight driver has only two functions to implement.  One function is
called when any of the above properties change (to update the backlight
brightness), the second is called to return the current backlight brightness
value.  A new attribute "actual_brightness" is added to return this brightness
as determined by the driver having combined all the above factors (and any
driver/device specific factors).

Additionally, the backlight core takes care of checking the maximum brightness
is not exceeded and of turning off the backlight before device removal.

The corgi backlight driver is updated to reflect these changes.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAntonino Daplas <adaplas@pol.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>