pwm_samsung_config() sets the manual update bit via a call to the
pwm_samsung_enable() function even when the channel is already running.
This causes noticable flicker on display if we try to change the
backlight brightness from minimum to maximum, continuously.

So, we remove the call to pwm_samsung_enable() from pwm_samsung_config
to avoid the flicker and this change doesn't harm normal working since
the pwm-backlight driver already calls pwm_samsung_enable() where
needed.
Signed-off-by: Ajay Kumar <ajaykumar.rs@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Read/write through I2C can sleep, thus set pwm_chip can_sleep flag.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

atmel_pwm_config() calls clk_get_rate() which might sleep, so we need to
set pwm_chip can_sleep flag.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The .config() calls clk_get_rate() which might sleep, so we need to set
pwm_chip can_sleep flag.  Otherwise, we see the following warning when
using PWM driven heartbeat led.

WARNING: CPU: 0 PID: 0 at kernel/locking/mutex.c:856 mutex_trylock+0x184/0x1a4()
DEBUG_LOCKS_WARN_ON(in_interrupt())
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 3.14.0-rc5 #18
[<c0015420>] (unwind_backtrace) from [<c0012cb0>] (show_stack+0x10/0x14)
[<c0012cb0>] (show_stack) from [<c001daf8>] (warn_slowpath_common+0x6c/0x8c)
[<c001daf8>] (warn_slowpath_common) from [<c001dbac>] (warn_slowpath_fmt+0x30/0x40)
[<c001dbac>] (warn_slowpath_fmt) from [<c045df74>] (mutex_trylock+0x184/0x1a4)
[<c045df74>] (mutex_trylock) from [<c0360950>] (clk_prepare_lock+0xc/0xec)
[<c0360950>] (clk_prepare_lock) from [<c0362020>] (clk_get_rate+0xc/0x68)
[<c0362020>] (clk_get_rate) from [<c028d07c>] (mxs_pwm_config+0x20/0x198)
[<c028d07c>] (mxs_pwm_config) from [<c028bde8>] (pwm_config+0x60/0x70)
[<c028bde8>] (pwm_config) from [<c034b61c>] (__led_pwm_set+0x1c/0x3c)
[<c034b61c>] (__led_pwm_set) from [<c034bc3c>] (led_heartbeat_function+0x70/0x110)
[<c034bc3c>] (led_heartbeat_function) from [<c00292f0>] (call_timer_fn+0x7c/0x164)
[<c00292f0>] (call_timer_fn) from [<c00295c8>] (run_timer_softirq+0x1f0/0x260)
[<c00295c8>] (run_timer_softirq) from [<c002255c>] (__do_softirq+0xc4/0x2f0)
[<c002255c>] (__do_softirq) from [<c0022890>] (irq_exit+0xa4/0x10c)
[<c0022890>] (irq_exit) from [<c0010240>] (handle_IRQ+0x34/0x84)
[<c0010240>] (handle_IRQ) from [<c0013524>] (__irq_svc+0x44/0x54)
[<c0013524>] (__irq_svc) from [<c00107f8>] (arch_cpu_idle+0x40/0x48)
[<c00107f8>] (arch_cpu_idle) from [<c005deb8>] (cpu_startup_entry+0x70/0x198)
[<c005deb8>] (cpu_startup_entry) from [<c060aac8>] (start_kernel+0x2a8/0x2f8)
Reported-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

These elementary functions should be inlined for fastest access. Also
fixes this warning as a side-effect (when no PM_SLEEP is selected):

drivers/pwm/pwm-tiehrpwm.c:141:12: warning: 'ehrpwm_read' defined but not used [-Wunused-function]
Signed-off-by: Wolfram Sang <wsa@sang-engineering.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Fixes following warnings on AM335X with no PM_SLEEP

drivers/pwm/pwm-tiehrpwm.c:534:13: warning: 'ehrpwm_pwm_save_context' defined but not used [-Wunused-function]
drivers/pwm/pwm-tiehrpwm.c:548:13: warning: 'ehrpwm_pwm_restore_context' defined but not used [-Wunused-function]
Signed-off-by: Wolfram Sang <wsa@sang-engineering.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The PWM core is now able to initialize the PWM period from a lookup
table defined by board files. Use it if available and fallback to the
value supplied in pwm_period_ns.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The PWM core is now able to initialize the PWM period from a lookup
table defined by board files. Use it if available and fallback to the
value supplied in pwm_period_ns.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Use the new variant of the PWM_LOOKUP macro to initialize the PWM lookup
table.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Use the new variant of the PWM_LOOKUP macro to initialize the PWM lookup
table.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Use the new variant of the PWM_LOOKUP macro to initialize the PWM lookup
table.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Now that PWM_LOOKUP is not used anymore, modify it to initialize all the
members of struct pwm_lookup.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Instead of relying on the .pwm_period_ns member of the pwm-backlight
driver's platform data, the PWM period can be retrieved from the PWM
lookup table.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The PWM core can retrieve the period from the PWM lookup table, so the
struct led_pwm.pwm_period_ns member can be removed.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The struct is not used anymore and the polarity initialization will be
done using the PWM lookup table (or device tree).
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Initializing all the struct pwm_lookup members allows to get rid of the
struct tpu_pwm_platform_data as the polarity initialization will be
taken care of by the PWM core.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Add period and polarity members to struct pwm_lookup so that platforms
using the lookup table can be treated the same way as those using the
device tree.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Current twl6030_pwm_disable() implementation writes TWL6030_TOGGLE3_REG
twice, the second write sets TWL6030_PWMXEN bits so the PWM clock does
not disable.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Fixes the following warnings reported by the 0-DAY kernel build testing
backend:

   drivers/pwm/pwm-lpss.c: In function 'pwm_lpss_probe_pci':
>> drivers/pwm/pwm-lpss.c:192:2: warning: passing argument 3 of 'pwm_lpss_probe' discards 'const' qualifier from pointer target type [enabled by default]
     lpwm = pwm_lpss_probe(&pdev->dev, &pdev->resource[0], info);
     ^
   drivers/pwm/pwm-lpss.c:130:30: note: expected 'struct pwm_lpss_boardinfo *' but argument is of type 'const struct pwm_lpss_boardinfo *'
    static struct pwm_lpss_chip *pwm_lpss_probe(struct device *dev,
                                 ^
>> drivers/pwm/pwm-lpss.c:143:28: sparse: incorrect type in return expression (different address spaces)
   drivers/pwm/pwm-lpss.c:143:28:    expected struct pwm_lpss_chip *
   drivers/pwm/pwm-lpss.c:143:28:    got void [noderef] <asn:2>*regs
>> drivers/pwm/pwm-lpss.c:192:63: sparse: incorrect type in argument 3 (different modifiers)
   drivers/pwm/pwm-lpss.c:192:63:    expected struct pwm_lpss_boardinfo *info
   drivers/pwm/pwm-lpss.c:192:63:    got struct pwm_lpss_boardinfo const *[assigned] info
   drivers/pwm/pwm-lpss.c: In function 'pwm_lpss_probe_pci':
   drivers/pwm/pwm-lpss.c:192:2: warning: passing argument 3 of 'pwm_lpss_probe' discards 'const' qualifier from pointer target type [enabled by default]
     lpwm = pwm_lpss_probe(&pdev->dev, &pdev->resource[0], info);
     ^
   drivers/pwm/pwm-lpss.c:130:30: note: expected 'struct pwm_lpss_boardinfo *' but argument is of type 'const struct pwm_lpss_boardinfo *'
    static struct pwm_lpss_chip *pwm_lpss_probe(struct device *dev,
                                 ^
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

pwmchip_add() returns zero on success and a negative value on error,
so the condition of the check must be inverted.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Switch to the new gpiod interface, which allows to handle GPIO
properties such as active low transparently and removes a whole bunch of
code.

There are still a couple of users of this driver that rely on passing
the enable GPIO number through platform data, so a fallback mechanism
using a GPIO number is still available to avoid breaking them. It will
be removed once current users have switched to the GPIO lookup tables
provided by the gpiod interface.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The pwm-backlight driver is moving to use the gpiod interface,
which has its own mapping mechanism for platform data GPIOs.
These mappings carry GPIO properties like active low so they don't have
to be explicitly handled by GPIO consumers.

Because of this change, the enable_gpio_flags member of
platform_pwm_backlight_data is going away. dev-backlight was passing
this member, but had no user making use of it, so it can safely be
removed. Further GPIOs used by pwm-backlight are expected to be
defined using the mechanisms provided by the gpiod API.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

When a device is shut down, make sure to disable the backlight. If it
stays lit, it gives the impression that the device hasn't turned off.
Furthermore keeping the backlight on may consume power, which is not
what users expect when they shut down a device.
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

Not all systems enumerate the PWM devices via ACPI. They can also be
exposed via the PCI interface.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Add support for the six-channel Kona PWM controller found on Broadcom
mobile SoCs like bcm281xx.
Signed-off-by: Tim Kryger <tim.kryger@linaro.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Reviewed-by: Markus Mayer <markus.mayer@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Add the binding description for the Kona PWM controller found on Broadcom's
mobile SoCs.
Signed-off-by: Tim Kryger <tim.kryger@linaro.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Reviewed-by: Markus Mayer <markus.mayer@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

The PWM subsystem defines normal and inversed PWM signal polarity in an
unambiguous way. In addition to the documentation in the linux/pwm.h
header file, add a paragraph in Documentation/pwm.txt because people are
likely to look there for guidance.
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Some versions of gcc even warn about it:

  mm/shmem.c: In function ‘shmem_file_aio_read’:
  mm/shmem.c:1414: warning: ‘error’ may be used uninitialized in this function

If the loop is aborted during the first iteration by one of the two
first break statements, error will be uninitialized.

Introduced by commit 6e58e79d ("introduce copy_page_to_iter, kill
loop over iovec in generic_file_aio_read()").
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

On 32 bit, size_t is "unsigned int", not "unsigned long", causing the
following warning when comparing with PAGE_SIZE, which is always "unsigned
long":

  fs/cifs/file.c: In function ‘cifs_readdata_to_iov’:
  fs/cifs/file.c:2757: warning: comparison of distinct pointer types lacks a cast

Introduced by commit 7f25bba8 ("cifs_iovec_read: keep iov_iter
between the calls of cifs_readdata_to_iov()"), which changed the
signedness of "remaining" and the code from min_t() to min().
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull slab changes from Pekka Enberg:
 "The biggest change is byte-sized freelist indices which reduces slab
  freelist memory usage:

    https://lkml.org/lkml/2013/12/2/64"

* 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux:
  mm: slab/slub: use page->list consistently instead of page->lru
  mm/slab.c: cleanup outdated comments and unify variables naming
  slab: fix wrongly used macro
  slub: fix high order page allocation problem with __GFP_NOFAIL
  slab: Make allocations with GFP_ZERO slightly more efficient
  slab: make more slab management structure off the slab
  slab: introduce byte sized index for the freelist of a slab
  slab: restrict the number of objects in a slab
  slab: introduce helper functions to get/set free object
  slab: factor out calculate nr objects in cache_estimate