pwm: rockchip: Fix period and duty cycle approximation

The current implementation always round down the duty and period values,
while it would be better to round them to the closest integer.

These

pwm: rockchip: Fix period and duty cycle approximation

The current implementation always round down the duty and period values,
while it would be better to round them to the closest integer.

These changes are needed in preparation of atomic update support to
prevent a period/duty cycle drift when executing several times the
'pwm_get_state() / modify / pwm_apply_state()' sequence.

Say you have an expected period of 3.333 us and a clk rate of
112.666667 MHz -- the clock frequency doesn't divide evenly, so the
period (stashed in nanoseconds) shrinks when we convert to the register
value and back, as follows:

pwm_apply_state(): register = period * 112666667 / 1000000000;
pwm_get_state(): period = register * 1000000000 / 112666667;

or in other words:

period = period * 112666667 / 1000000000 * 1000000000 / 112666667;

which yields a sequence like:

3333 -> 3328
3328 -> 3319
3319 -> 3310
3310 -> 3301
3301 -> 3292
3292 -> ... (etc) ...

With this patch, we'd see instead:

period = div_round_closest(period * 112666667, 1000000000) *
1000000000 / 112666667;

which yields a stable sequence:

3333 -> 3337
3337 -> 3337
3337 -> ... (etc) ...

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

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Merge remote-tracking branch 'linusw-gpio/for-next' into devm_gpiochip

Base for demv_gpiochip_add_data() and devm_gpiochip_remove().

Merge branch 'next' into for-linus

Prepare first round of input updates for 4.3 merge window.

Merge branch 'for-4.3-fixes' into for-4.4

Merge branch 'x86/urgent' into core/efi, to pick up a pending EFI fix

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge remote-tracking branch 'net-next/master' into mac80211-next

Merge net-next to get some driver changes that patches depend
on (in order to avoid conflicts).

Signed-off-by: Johannes Berg <johan

Merge remote-tracking branch 'net-next/master' into mac80211-next

Merge net-next to get some driver changes that patches depend
on (in order to avoid conflicts).

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

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Merge remote-tracking branch 'asoc/fix/rt5645' into asoc-fix-rt5645

Merge branch 'for-4.3-rc/ti-clk-fixes' of https://github.com/t-kristo/linux-pm into clk-fixes

Pull fixes from Tero Kristo:

"A few TI clock driver fixes to pull against 4.3-rc"

* 'for-4.3-rc/ti-clk

Merge branch 'for-4.3-rc/ti-clk-fixes' of https://github.com/t-kristo/linux-pm into clk-fixes

Pull fixes from Tero Kristo:

"A few TI clock driver fixes to pull against 4.3-rc"

* 'for-4.3-rc/ti-clk-fixes' of https://github.com/t-kristo/linux-pm: (3 commits)
clk: ti: dflt: fix enable_reg validity check
clk: ti: fix dual-registration of uart4_ick
clk: ti: clk-7xx: Remove hardwired ABE clock configuration

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Merge remote-tracking branch 'airlied/drm-next' into drm-intel-next

Backmerge to catch up with 4.3. slightly more involved conflict in the
irq code, but nothing beyond adjacent changes.

Signed-off-

Merge remote-tracking branch 'airlied/drm-next' into drm-intel-next

Backmerge to catch up with 4.3. slightly more involved conflict in the
irq code, but nothing beyond adjacent changes.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

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Merge tag 'v4.3-rc3' into next

Merge with Linux 4.3-rc3 to bring in MFD DA9062 changes to merge DA9062
OnKey driver.

Merge tag 'v4.3-rc2' into k.o/for-4.3-v1

Linux 4.3-rc2

Merge tag 'v4.3-rc2' into topic/drm-misc

Backmerge Linux 4.3-rc2 because of conflicts in the dp helper code
between bugfixes and new code. Just adjacent lines really.

On top of that there's a silen

Merge tag 'v4.3-rc2' into topic/drm-misc

Backmerge Linux 4.3-rc2 because of conflicts in the dp helper code
between bugfixes and new code. Just adjacent lines really.

On top of that there's a silent conflict in the new fsl-dcu driver
merged into 4.3 and

commit 844f9111f6f54f88eb2f0fac121b82ce77193866
Author: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Date: Wed Sep 2 10:42:40 2015 +0200

drm/atomic: Make prepare_fb/cleanup_fb only take state, v3.

which Thierry Reding spotted and provided a fixup for.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

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Merge branch 'for-linus' into for-next

Merge tag 'v4.3-rc1' into spi-fix-doc

Linux 4.3-rc1

Merge branch 'fixes-rc1' into omap-for-v4.3/fixes

Merge tag 'v4.3-rc1' into MTD -next development

Merge tag 'v4.3-rc1' into patchwork

Linux 4.3-rc1

* tag 'v4.3-rc1': (11838 commits)
Linux 4.3-rc1
blk: rq_data_dir() should not return a boolean
writeback: plug writeback in wb_writeback() an

Merge tag 'v4.3-rc1' into patchwork

Linux 4.3-rc1

* tag 'v4.3-rc1': (11838 commits)
Linux 4.3-rc1
blk: rq_data_dir() should not return a boolean
writeback: plug writeback in wb_writeback() and writeback_inodes_wb()
thermal: fix intel PCH thermal driver mismerge
ARCv2: [axs103_smp] Reduce clk for SMP FPGA configs
revert "ocfs2/dlm: use list_for_each_entry instead of list_for_each"
mm/early_ioremap: add explicit #include of asm/early_ioremap.h
fs/seq_file: convert int seq_vprint/seq_printf/etc... returns to void
selftests: enhance membarrier syscall test
selftests: add membarrier syscall test
sys_membarrier(): system-wide memory barrier (generic, x86)
MODSIGN: fix a compilation warning in extract-cert
Revert "writeback: plug writeback at a high level"
scsi_dh: fix randconfig build error
target: use stringify.h instead of own definition
target/user: Fix UFLAG_UNKNOWN_OP handling
target: Remove no-op conditional
target/user: Remove unused variable
target: Fix max_cmd_sn increment w/o cmdsn mutex regressions
target: Attach EXTENDED_COPY local I/O descriptors to xcopy_pt_sess
...

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Merge tag 'v4.3-rc1' into perf/core, to refresh the tree

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'v4.3-rc1' into locking/core, to refresh the tree

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'v4.3-rc1' into sched/core, to refresh the branch

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'pwm/for-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
"This set of changes introduces the beginnings of a new A

Merge tag 'pwm/for-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
"This set of changes introduces the beginnings of a new API that's
based around the concept of states that can be atomically applied.
Drivers go to various lengths to implement something similar, which
indicates that the core should really be providing the necessary
framework.

On top of that, there is a bit of cleanup as well as improved
kerneldoc and integration into the device-drivers DocBook.

Regarding drivers there is a new one for the NXP LPC18xx family of
SoCs and a couple of fixes for existing drivers (pca9685, Broadcom
Kona and Atmel HLCDC)"

* tag 'pwm/for-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
ARM: at91: pwm: atmel-hlcdc: Add at91sam9n12 errata
pwm: Add NXP LPC18xx PWM/SCT DT binding documentation
pwm: NXP LPC18xx PWM/SCT driver
pwm-pca9685: Support changing the output frequency
pwm-pca9685: Fix several driver bugs
pwm: kona: Modify settings application sequence
pwm: pca9685: Drop owner assignment
pwm: Add to device-drivers documentation
pwm: Clean up kerneldoc
pwm: Remove useless whitespace
pwm: sysfs: Remove unnecessary padding
pwm: sysfs: Properly convert from enum to string
pwm: Make use of pwm_get_xxx() helpers where appropriate
pwm: Add pwm_get_polarity() helper function
pwm: Constify PWM device where possible
pwm: Add the pwm_is_enabled() helper

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pwm: Make use of pwm_get_xxx() helpers where appropriate

Use the pwm_get_xxx() helpers instead of directly accessing the fields
in struct pwm_device. This will allow us to smoothly move to the atomi

pwm: Make use of pwm_get_xxx() helpers where appropriate

Use the pwm_get_xxx() helpers instead of directly accessing the fields
in struct pwm_device. This will allow us to smoothly move to the atomic
update approach.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

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Merge branch 'next' into for-linus

Prepare first round of input updates for 3.20.

Merge tag 'v3.19-rc4' into next

Merge with mainline to bring in the latest thermal and other changes.

Merge branches 'arm/omap', 'arm/msm', 'arm/rockchip', 'arm/renesas', 'arm/smmu', 'x86/vt-d', 'x86/amd' and 'core' into next

Conflicts:
drivers/iommu/arm-smmu.c