TI LP8788 PMU has the current sink as the keyboard led driver.
The brightness is controlled by the i2c commands.
Configurable parameters can be defined in the platform side.

Patch v2.
(a) use workqueue on changing the brightness

(b) use mutex_lock/unlock when the brightness is set
    and the led block of lp8788 device is enabled

(c) remove err_dev on _probe()
    : just return as returned value if any errors

(d) replace module_init/exit() with module_platform_driver()

(e) add led configuration structure and loading them by default
    if platform data is null
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Add driver for BlinkM device to drivers/leds/.
Add entry to MAINTAINERS file.
Add documentation in Documentation/leds/.

A BlinkM is a RGB LED controlled through I2C.

This driver implements an interface to the LED framework
and another sysfs group to access the internal options
of the BlinkM.

rev6: Use module_i2c_driver().
rev5: Removed own workqueue in favor of events wq.
rev4: Fixed comments by Bryan Wu.
rev3: Fixed issues found by Jonathan Neuschäfer.

(bryan.wu@canonical.com: remove 2 trailing whitespace)
Signed-off-by: Jan-Simon Möller <jansimon.moeller@gmx.de>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

It is not necessary to call max8997_update_reg() twice just for updating
MAX8997_REG_LEN_CNTL register. With proper val and mask arguments to
max8997_update_reg() call, this can be done in one max8997_update_reg() call.
And then we can remove max8997_led_clear_mode() function.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

why?
because if the led_classdev_register fails we wont do gpio free
because using devm_ functions, there is no need for error paths
Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Simon Guinot <sguinot@lacie.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Guennadi Liakhovetski <lg@denx.de>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Philippe Retornaz <philippe.retornaz@epfl.ch>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Michael Hennerich <hennerich@blackfin.uclinux.org>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Nate Case <ncase@xes-inc.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Magnus Damm <damm@opensource.se>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Mathias Nyman <mathias.nyman@nokia.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Peter Meerwald <p.meerwald@bct-electronic.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Kim Kyuwon <q1.kim@samsung.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Eric Miao <eric.miao@canonical.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Antonio Ospite <ospite@studenti.unina.it>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Cc: Simon Guinot <sguinot@lacie.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

devm_kzalloc() makes cleanup simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

devm_kzalloc() makes code cleanup simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

devm_kzalloc() makes cleanup simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

devm_kzalloc() makes cleanup simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

module_platform_driver() makes the code simpler.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Signed-off-by: Peter Meerwald <p.meerwald@bct-electronic.com>
Cc: NeilBrown <neilb@suse.de>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

The s3c2410_gpio* calls are obsolete and have been scheduled for
removal since several kernel releases. Remove them and use common
gpiolib API instead.
This patch also adds gpio_request/gpio_free call for API corectness.

It is a prerequisite for removal of the S3C24XX SoC specific
arch/arm/plat-samsung/include/gpio-fns.h header.

Tested on Micro2440-SDK.

Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Use the device managed resource API for simplifying
the error/driver remove paths.

Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

the platform_set_drvdata (pdev, NULL) to be set at the remove of the
driver, as we have set the platform data to led at probe.
Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Using devm_kzalloc will remove all the error checks and the frees are automatically done at the driver unload side.
Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Inside the error handling in lp5523_init_led(), there is a place that
calls to led_classdev_unregister().  When we unregister the LED drivers,
it tries to set the brightness to OFF.  In this driver setting the
brightness is done through a work queue and the work queue hasn't been
initialized yet.

The result is that we trigger a WARN_ON() in the __queue_work().

The fix is to move the INIT_WORK() in front of the call to
lp5523_init_led().

Matt Renzelmann found this using a bug finding tool.
Reported-by: Matt Renzelmann <mjr@cs.wisc.edu>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

LM3556 :
The LM3556 is a 4 MHz fixed-frequency synchronous boost
converter plus 1.5A constant current driver for a high-current white LED.
Datasheet: www.national.com/ds/LM/LM3556.pdf

Tested on OMAP4430

(bryan.wu@canonical.com: use module_i2c_driver() rather than
lm3556_init/lm3556_exit for code simplicity; fixed some typo
pointed out by Rob Landley)
Signed-off-by: G.Shark Jeong <gshark.jeong@gmail.com>
Reviewed-by: Axel Lin <axel.lin@gmail.com>
Reviewed-by: Kim, Milo <Milo.Kim@ti.com>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

the ret is got the status returned by the
led_classdev_register, returning ret if the
led_classdev_register fails and returning 0
if the led_classdev_register success, can be done
by doing just "return ret" at the end.
Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

drivers/leds/led-core.c:56:6: sparse: symbol 'led_blink_setup' was not declared. Should it be static?
drivers/leds/led-triggers.c:233:6: sparse: symbol 'led_trigger_blink_setup' was not declared. Should it be static?
Reported-by: Fengguang Wu <wfg@linux.intel.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Correct "hadrware" to "hardware", for LEDS_TRIGGER_TRANSIENT.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

Fix led_trigger_event() to use led_set_brightness() instead of
__led_set_brightness(), so that any pending blink timer is stopped before
setting the new brightness value.  Without this fix LED status may be
overridden by a pending timer.

This allows a trigger to use a mix of led_trigger_event(),
led_trigger_blink() and led_trigger_blink_oneshot() without races.

(applied over: leds: Rename led_brightness_set() to led_set_brightness())
Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Cc: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>