As each led device gets registered a kernel message gets printed. In
an embedded system with a number of leds this can produce a lot
of output that just looks like noise.

Change the message type to KERN_DEBUG since it might be useful
in the dmesg output "after" booting.
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

Makes use of skip_spaces() defined in lib/string.c for removing leading
spaces from strings all over the tree.

It decreases lib.a code size by 47 bytes and reuses the function tree-wide:
   text    data     bss     dec     hex filename
  64688     584     592   65864   10148 (TOTALS-BEFORE)
  64641     584     592   65817   10119 (TOTALS-AFTER)

Also, while at it, if we see (*str && isspace(*str)), we can be sure to
remove the first condition (*str) as the second one (isspace(*str)) also
evaluates to 0 whenever *str == 0, making it redundant. In other words,
"a char equals zero is never a space".

Julia Lawall tried the semantic patch (http://coccinelle.lip6.fr) below,
and found occurrences of this pattern on 3 more files:
    drivers/leds/led-class.c
    drivers/leds/ledtrig-timer.c
    drivers/video/output.c

@@
expression str;
@@

( // ignore skip_spaces cases
while (*str &&  isspace(*str)) { \(str++;\|++str;\) }
|
- *str &&
isspace(*str)
)
Signed-off-by: NAndré Goddard Rosa <andre.goddard@gmail.com>
Cc: Julia Lawall <julia@diku.dk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Neil Brown <neilb@suse.de>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: David Howells <dhowells@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch allows drivers to override the default maximum brightness value
of 255.  We take care to preserve backwards-compatibility as much as
possible, so that user-space ABI doesn't change for existing drivers.
LED trigger code has also been updated to use the per-LED maximum.
Signed-off-by: NGuennadi Liakhovetski <lg@denx.de>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

Add suspend/resume to the core class and remove all the now unneeded
code from various drivers. Originally the class code couldn't support
suspend/resume but since class_device can there is no reason for
each driver doing its own suspend/resume anymore.

Signed-off-by: NSven Wegener <sven.wegener@stealer.net>
Signed-off-by: NRichard Purdie <rpurdie@intel.linux.com>

Fix a race during trigger registration where we could try and use a lock
before it was initialised.
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

led_classdev_unregister() has no "__" prefix, remove it.
Signed-off-by: NQinghuang Feng <qhfeng.kernel@gmail.com>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

There's no need for the additional call to strlen(), we can directly
return the value returned by sprintf().  We now return a length value
that doesn't include the final '\0', but user space shouldn't bother
about it anyway.
Signed-off-by: NSven Wegener <sven.wegener@stealer.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

Now that device_create() has been audited, rename things back to the
original call to be sane.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

There is a race from when a device is created with device_create() and
then the drvdata is set with a call to dev_set_drvdata() in which a
sysfs file could be open, yet the drvdata will be NULL, causing all
sorts of bad things to happen.

This patch fixes the problem by using the new function,
device_create_drvdata().

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Some drivers have duplicated unlikely() macros.  IS_ERR() already has
unlikely() in itself.

This patch cleans up such pointless code.
Signed-off-by: NHirofumi Nakagawa <hnakagawa@miraclelinux.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NJeff Garzik <jeff@garzik.org>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some led hardware allows drivers to query the led state, and this patch
adds a hook to let the led class take advantage of that information when
available.

Without this functionality, when access to the led hardware is not
exclusive (i.e. firmware or hardware might change its state behind the
kernel's back), reality goes out of sync with the led class' idea of what
the led is doing, which is annoying at best.

Behaviour for drivers that do not or cannot read the led status is
unchanged.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>

Disable any active triggers when the brightness attribute is
set to zero.
Signed-off-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NMárton Németh <nm127@freemail.hu>
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>

After 2.6.24 there was a plan to make the PM core acquire all device
semaphores during a suspend/hibernation to protect itself from
concurrent operations involving device objects.  That proved to be
too heavy-handed and we found a better way to achieve the goal, but
before it happened, we had introduced the functions
device_pm_schedule_removal() and destroy_suspended_device() to allow
drivers to "safely" destroy a suspended device and we had adapted some
drivers to use them.  Now that these functions are no longer necessary,
it seems reasonable to remove them and modify their users to use the
normal device unregistration instead.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Make it possible to unregister a led classdev object in a safe way during a
suspend/resume cycle.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Covert leds_list_lock to a rw_sempahore to match previous LED trigger
locking fixes, fixing lock ordering.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>

Convert part of the led trigger core from rw spinlocks to rw
semaphores. We're calling functions which can sleep from invalid
contexts otherwise. Fixes bug #9264.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>

Convert the LEDs class from struct class_device to struct device
since class_device is scheduled for removal.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NJeff Garzik <jeff@garzik.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fixes a typo in led-class.c kerneldoc.
Signed-off-by: NHenrik Kretzschmar <henne@nachtwindheim.de>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

Signed-off-by: NJörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

Fix the error handling of some LED _store functions.  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>

Add support for LED triggers to the LED subsystem.  "Triggers" are events
which change the state of an LED.  Two kinds of trigger are available, simple
ones which can be added to exising code with minimum disruption and complex
ones for implementing new or more complex functionality.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add the foundations of a new LEDs subsystem.  This patch adds a class which
presents LED devices within sysfs and allows their brightness to be
controlled.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>