Commit Graph

600183 Commits

Author SHA1 Message Date
Boris Brezillon
d81d8e4b87 UPSTREAM: regulator: pwm: Support extra continuous mode cases
The continuous mode allows one to declare a PWM regulator without having
to declare the voltage <-> dutycycle association table. It works fine as
long as your voltage(dutycycle) function is linear, but also has the
following constraints:

- dutycycle for min_uV = 0%
- dutycycle for max_uV = 100%
- dutycycle for min_uV < dutycycle for max_uV

While the linearity constraint is acceptable for now, we sometimes need to
restrict of the PWM range (to limit the maximum/minimum voltage for
example) or have a min_uV_dutycycle > max_uV_dutycycle (this could be
tweaked with PWM polarity, but not all PWMs support inverted polarity).

Add the pwm-dutycycle-range and pwm-dutycycle-unit DT properties to define
such constraints. If those properties are not defined, the PWM regulator
use the default pwm-dutycycle-range = <0 100> and
pwm-dutycycle-unit = <100> values (existing behavior).

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>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit ea398e2873)

Change-Id: I6e10c93a6620113e1463221d461fc23ccf3fe398
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
d86d501a10 UPSTREAM: pwm: rockchip: Add support for atomic update
Implement the ->apply() function to add support for atomic update.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(commit 2bf1c98aa5)

Conflicts:
	drivers/pwm/pwm-rockchip.c

Change-Id: I92745cf301c26d20da284da8234e244828598d52
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
370a8d95d4 UPSTREAM: pwm: rockchip: Avoid glitches on already running PWMs
The current logic will disable the PWM clk even if the PWM was left
enabled by the bootloader (because it's controlling a critical device
like a regulator for example).
Keep the PWM clk enabled if the PWM is enabled to avoid any glitches.

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>
(commit 48cf973cae)

Conflicts:
	drivers/pwm/pwm-rockchip.c

Change-Id: I75ffccd19c5244568fc0034d1585dac490296111
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
c365d86972 UPSTREAM: pwm: rockchip: Add support for hardware readout
Implement the ->get_state() function to expose initial state.

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>
(cherry picked from commit 1ebb74cf35)

Change-Id: Ia7454ce2f96ee814118724fa98bdd41d8b5ae922
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
d0a5c68483 UPSTREAM: 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>
(cherry picked from commit 12f9ce4a51)

Change-Id: Ife75404e663d1380725d634ac621b2ca9f831791
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
ccdd153753 UPSTREAM: regulator: pwm: Retrieve correct voltage
The continuous PWM voltage regulator is caching the voltage value in
the ->volt_uV field. While most of the time this value should reflect the
real voltage, sometime it can be sightly different if the PWM device
rounded the set_duty_cycle request.
Moreover, this value is not valid until someone has modified the regulator
output.

Remove the ->volt_uV field and always rely on the PWM state to calculate
the regulator output.

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>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit d9070fdbe4)

Change-Id: Iba7b143c1b08d547b5cd46ac42d9051fb34309df
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
cada6fee2f UPSTREAM: regulator: pwm: Properly initialize the ->state field
The ->state field is currently initialized to 0, thus referencing the
voltage selector at index 0, which might not reflect the current
voltage value.
If possible, retrieve the current voltage selector from the PWM state,
else return -EINVAL.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Brian Norris <briannorris@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 87248991a1)

Change-Id: I179395dc7bad7aa867e68c92be7ce92b03ae7112
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
d9e3d266ec UPSTREAM: regulator: pwm: Switch to the atomic PWM API
Use the atomic API wherever appropriate and get rid of pwm_apply_args()
call (the reference period and polarity are now explicitly set when
calling pwm_apply_state()).

We also make use of the pwm_set_relative_duty_cycle() helper to ease
relative to absolute duty_cycle conversion.

Note that changes introduced by commit fd786fb027 ("regulator: pwm:
Try to avoid voltage error in duty cycle calculation") are no longer
needed because pwm_set_relative_duty_cycle() takes care of all rounding
approximation for us.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 3f4eb39be9)

Change-Id: Id12d4d625fb6e1e5ff3725737cc9232e4df40c36
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
5452a5568c UPSTREAM: regulator: pwm: Adjust PWM config at probe time
The PWM attached to a PWM regulator device might have been previously
configured by the bootloader.
Make sure the bootloader and linux config are in sync, and adjust the PWM
config if that's not the case.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-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>
(cherry picked from commit fd4f99c4c3)

Change-Id: I06abddddc4666cd6510b6317795931f282e44eb0
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Thierry Reding
96e741fe6b UPSTREAM: pwm: Remove gratuitous blank line
Commit 5ec803edcb ("pwm: Add core infrastructure to allow atomic
updates") introduced this double blank line by mistake.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 2b77487f2e)

Change-Id: Ie84fc2496ae6ca111386fa42ab31b8ab0559bece
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
4898ef2167 UPSTREAM: pwm: Add relative duty cycle manipulation helpers
The PWM framework expects PWM users to configure the duty cycle in nano-
seconds, but many users want to express the duty cycle relatively to the
period value (i.e. duty_cycle = 33% of the period).

Add the pwm_{get,set}_relative_duty_cycle() helpers to ease this kind of
conversion.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit f6f3bddf7b)

Change-Id: Ifffc72290225766a6006db6b18e6902ee51adb1c
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
1889e37ad5 UPSTREAM: pwm: Add a helper to prepare a new PWM state
The pwm_init_state() helper prepares a new state object containing the
current PWM state except for the polarity and period fields which are
set to the reference values (those in struct pwm_args).

This is particularly useful for PWM users who want to apply a new duty-
cycle expressed relatively to the reference period without changing the
enable state.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit a6a0dbbcfa)

Change-Id: Ib968e8fa6a49d5f853fc13cb4935e2af7494040f
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Douglas Anderson
89ae836944 UPSTREAM: regulator: pwm: Fix regulator ramp delay for continuous mode
The original commit adding support for continuous voltage mode didn't
handle the regulator ramp delay properly.  It treated the delay as a
fixed delay in uS despite the property being defined as uV / uS.  Let's
adjust it.  Luckily there appear to be no users of this ramp delay for
PWM regulators (as per grepping through device trees in linuxnext).

Note also that the upper bound of usleep_range probably shouldn't be a
full 1 ms longer than the lower bound since I've seen plenty of hardware
with a ramp rate of ~5000 uS / uV and for small jumps the total delays
are in the tens of uS.  1000 is way too much.  We'll try to be dynamic
and use 10%.

NOTE: This commit doesn't add support for regulator-enable-ramp-delay.
That could be done in a future patch when someone has a user of that
featre.

Though this patch is shows as "fixing" a bug, there are no actual known
users of continuous mode PWM regulator w/ ramp delay in mainline and so
this likely won't have any effect on anyone unless they are working
out-of-tree with private patches.  For anyone in this state, it is
highly encouraged to also pick Boris Brezillon's WIP patches to get
yourself a reliable and glitch-free regulator.

Fixes: 4773be185a ("regulator: pwm-regulator: Add support for continuous-voltage")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit c2588393e6)

Change-Id: Ib0af8e04275813f333af12d48567b7e411b4d49f
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
19994c65c7 UPSTREAM: pwm: Fix pwm_apply_args()
Commit 5ec803edcb ("pwm: Add core infrastructure to allow atomic
updates"), implemented pwm_disable() as a wrapper around
pwm_apply_state(), and then, commit ef2bf4997f ("pwm: Improve args
checking in pwm_apply_state()") added missing checks on the ->period
value in pwm_apply_state() to ensure we were not passing inappropriate
values to the ->config() or ->apply() methods.

The conjunction of these 2 commits led to a case where pwm_disable()
was no longer succeeding, thus preventing the polarity setting done
in pwm_apply_args().

Set a valid period in pwm_apply_args() to ensure polarity setting
won't be rejected.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Suggested-by: Brian Norris <briannorris@chromium.org>
Fixes: 5ec803edcb ("pwm: Add core infrastructure to allow atomic updates")
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 33cdcee04b)

Change-Id: I9f28ae411953208b31c8d17214fce21e5177cee1
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Alexandre Courbot
60dc7d8eda UPSTREAM: regulator: pwm: Support for enable GPIO
Add an optional enable GPIO to the pwm-regulator driver.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 27bfa8893b)

Change-Id: I6530165e6bccb4fc82d2916d169a02ecdcbfcd3e
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Lee Jones
ea5d08da89 UPSTREAM: pwm: sysfs: Add PWM capture support
Allow a user to read PWM capture results from sysfs. To start a capture
and read the result, simply read the file:

  $ cat $PWMCHIP/capture

The output format is "<period> <duty cycle>".

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 1a366fe915)

Change-Id: I86326709c373630a9189232a1cf2804a1a6ed380
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Lee Jones
76e1d28062 UPSTREAM: pwm: Add PWM capture support
Supply a PWM capture callback op in order to pass back information
obtained by running analysis on a PWM signal. This would normally (at
least during testing) be called from the sysfs routines with a view to
printing out PWM capture data which has been encoded into a string.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
[thierry.reding@gmail.com: make capture data unsigned int for symmetry]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

(cherry picked from commit 3a3d1a4e32)

Change-Id: Iee3acf2eb02c5282d586f4e7f1745031e17cc383
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Ryo Kodama
9d523c1462 UPSTREAM: pwm: sysfs: Get return value from pwm_apply_state()
This patch adds to check the return value from pwm_apply_state()
used in enable_store(). The error of enable_store() doesn't work
if the return value doesn't received.

Signed-off-by: Ryo Kodama <ryo.kodama.vz@renesas.com>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Fixes: 39100ceea7 ("pwm: Switch to the atomic API")
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit fe5aa34d6e)

Change-Id: I550da28345bcee7a6aa8e1f9b5c43adae923ff2d
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Brian Norris
5e88e30e7e UPSTREAM: pwm: Improve args checking in pwm_apply_state()
It seems like in the process of refactoring pwm_config() to utilize the
newly-introduced pwm_apply_state() API, some args/bounds checking was
dropped.

In particular, I noted that we are now allowing invalid period
selections, e.g.:

  # echo 1 > /sys/class/pwm/pwmchip0/export
  # cat /sys/class/pwm/pwmchip0/pwm1/period
  100
  # echo 101 > /sys/class/pwm/pwmchip0/pwm1/duty_cycle
  [... driver may or may not reject the value, or trigger some logic bug ...]

It's better to see:

  # echo 1 > /sys/class/pwm/pwmchip0/export
  # cat /sys/class/pwm/pwmchip0/pwm1/period
  100
  # echo 101 > /sys/class/pwm/pwmchip0/pwm1/duty_cycle
  -bash: echo: write error: Invalid argument

This patch reintroduces some bounds checks in both pwm_config() (for its
signed parameters; we don't want to convert negative values into large
unsigned values) and in pwm_apply_state() (which fix the above described
behavior, as well as other potential API misuses).

Fixes: 5ec803edcb ("pwm: Add core infrastructure to allow atomic updates")
Signed-off-by: Brian Norris <briannorris@chromium.org>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit ef2bf4997f)

Change-Id: I7d7515a51b5c3c2a77ae9743b7ed69eedc11d4b4
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
d1b4c71db8 UPSTREAM: regulator: pwm: Drop unneeded pwm_enable() call
Now that the PWM regulator driver implements the ->enable/disable() hooks
we can remove the pwm_enable() call from pwm_regulator_set_voltage().

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 830583004e)

Change-Id: I89fba9a44d98ed94ede099b841b7358ba4011e35
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Heiko Stübner
0cb6a1b23b UPSTREAM: pwm: Add information about polarity, duty cycle and period to debugfs
The PWM states make it possible to also output the polarity, duty cycle
and period information in the debugfs summary output. This simplifies
gathering information about PWMs without needing to walk through the
sysfs attributes of every PWM.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[thierry.reding@gmail.com: use more spaces in debugfs output]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

(cherry picked from commit 23e3523f5d)

Change-Id: Ia5d4d9ab898510d07364ad455ccf93e1c1d95d2b
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
a5721888cd UPSTREAM: pwm: Switch to the atomic API
Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls
by pwm_get/apply_state().

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 39100ceea7)

Change-Id: I01fe340686c044e22c8e78f0a6f6995dc82b440a
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
3f49705613 UPSTREAM: pwm: Update documentation
Update the PWM subsystem documentation to reflect the atomic PWM
changes.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit a07136fdcf)

Change-Id: I04796750d3da1b7e7fd9eb0e4a2c900796fbd126
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
7da6121026 UPSTREAM: pwm: Add core infrastructure to allow atomic updates
Add an ->apply() method to the pwm_ops struct to allow PWM drivers to
implement atomic updates. This method is preferred over the ->enable(),
->disable() and ->config() methods if available.

Add the pwm_apply_state() function to the PWM user API.

Note that the pwm_apply_state() does not guarantee the atomicity of the
update operation, it all depends on the availability and implementation
of the ->apply() method.

pwm_enable/disable/set_polarity/config() are now implemented as wrappers
around the pwm_apply_state() function.

pwm_adjust_config() is allowing smooth handover between the bootloader
and the kernel. This function tries to adapt the current PWM state to
the PWM arguments coming from a PWM lookup table or a DT definition
without changing the duty_cycle/period proportion.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[thierry.reding@gmail.com: fix a couple of typos]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

(cherry picked from commit 5ec803edcb)

Change-Id: Ib527f34ca3ce90ded3b48725d7ab9509de2053c9
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
92c320f5e4 UPSTREAM: pwm: Add hardware readout infrastructure
Add a ->get_state() function to the pwm_ops struct to let PWM drivers
initialize the PWM state attached to a PWM device.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 15fa8a43c1)

Change-Id: Ie37be2d34833cbb6cc4b4b4cb6af98ac721b953a
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
8ea6738fe0 UPSTREAM: pwm: Move the enabled/disabled info into pwm_state
Prepare the transition to PWM atomic update by moving the enabled and
disabled state into the pwm_state struct. This way we can easily update
the whole PWM state by copying the new state in the ->state field.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 09a7e4a3d9)

Change-Id: I38808d868c7e73f0ffd49cfb6c0b4b45fa911613
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
46307ce2a6 UPSTREAM: pwm: Introduce the pwm_state concept
The PWM state, represented by its period, duty_cycle and polarity is
currently directly stored in the PWM device. Declare a pwm_state
structure embedding those field so that we can later use this struct
to atomically update all the PWM parameters at once.

All pwm_get_xxx() helpers are now implemented as wrappers around
pwm_get_state().

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 43a276b003)

Change-Id: I44037440bcc9d9164d18f3bfa1c8ff3e593925c5
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
3805a86892 UPSTREAM: pwm: Keep PWM state in sync with hardware state
Before the introduction of pwm_args, the core was resetting the PWM
period and polarity states to the reference values (those provided
through the DT, a PWM lookup table or hardcoded in the driver).

Now that all PWM users are correctly using pwm_args to configure their
PWM device, we can safely remove the pwm_apply_args() call in pwm_get()
and of_pwm_get().

We can also get rid of the pwm_set_period() call in pwm_apply_args(),
because PWM users are now directly using pargs->period instead of
pwm_get_period(). By doing that we avoid messing with the current PWM
period.

The only remaining bit in pwm_apply_args() is the initial polarity
setting, and it should go away when all PWM users have been patched to
use the atomic API (with this API the polarity will be set along with
other PWM arguments when configuring the PWM).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit a8c3862551)

Change-Id: I5112f2d8a7b66e01184984376dcae84decf5ad28
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
9d99f123ad UPSTREAM: backlight: pwm_bl: Use pwm_get_args() where appropriate
The PWM framework has clarified the concept of reference PWM config (the
platform dependent config retrieved from the DT or the PWM lookup table)
and real PWM state.

Use pwm_get_args() when the PWM user wants to retrieve this reference
config and not the current state.

This is part of the rework allowing the PWM framework to support
hardware readout and expose real PWM state even when the PWM has just
been requested (before the user calls pwm_config/enable/disable()).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 6cb9644db7)

Change-Id: Idc29a17716d439962b50db156c13b65abd852d90
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
e4041f3958 UPSTREAM: regulator: pwm: Use pwm_get_args() where appropriate
The PWM framework has clarified the concept of reference PWM config (the
platform dependent config retrieved from the DT or the PWM lookup table)
and real PWM state.

Use pwm_get_args() when the PWM user wants to retrieve this reference
config and not the current state.

This is part of the rework allowing the PWM framework to support
hardware readout and expose real PWM state even when the PWM has just
been requested (before the user calls pwm_config/enable/disable()).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from 8c12ad8e91)

Conflicts:
	drivers/regulator/pwm-regulator.c

Change-Id: Id7fb1d823db7a0be207de4f0393e6c86df143335
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris BREZILLON
3f4e6dcb3d UPSTREAM: pwm: Get rid of pwm->lock
PWM devices are not protected against concurrent accesses. The lock in
struct pwm_device might let PWM users think it is, but it's actually
only protecting the enabled state.

Removing this lock should be fine as long as all PWM users are aware
that accesses to the PWM device have to be serialized, which seems to be
the case for all of them except the sysfs interface. Patch the sysfs
code by adding a lock to the pwm_export struct and making sure it's
taken for all relevant accesses to the exported PWM device.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 459a25afe9)

Change-Id: I30d97ebaf1db8b80c353da5ebebd0fc5d5c57bb0
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris BREZILLON
a0a5f14bc8 UPSTREAM: backlight: pwm_bl: Remove useless call to pwm_set_period()
The PWM period will be set when calling pwm_config. Remove this useless
call to pwm_set_period(), which might mess up the internal PWM state.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 7f044b09b6)

Change-Id: I6eecc6cd8e9dbe5929bdc016433772a721711928
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
394b99f37d UPSTREAM: pwm: Fix pwm_apply_args() call sites
pwm_apply_args() is supposed to initialize a PWM device according to the
arguments provided by the DT or the PWM lookup, but this function was
called inside pwm_device_request(), which in turn was called before the
core had a chance to initialize the pwm->args fields.

Fix that by calling pwm_apply_args directly in pwm_get() and of_pwm_get()
after initializing pwm->args field.

This commit also fixes an invalid pointer dereference introduced by
commit e39c0df1be ("pwm: Introduce the pwm_args concept").

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Fixes: e39c0df1be ("pwm: Introduce the pwm_args concept")
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit fbd45a1298)

Change-Id: I9746f4ada57a6cc8155bafe662a63c82338c223a
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Aaron Lu
55d922eb73 UPSTREAM: video / backlight: remove the backlight_device_registered API
Since we will need the backlight_device_get_by_type API, we can use it
instead of the backlight_device_registered API whenever necessary so
remove the backlight_device_registered API.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from commit 01c3664de6)

Change-Id: I12fdee74963c2cbc5b950019598ec218de1b7b5d
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Aaron Lu
2d30b518c9 UPSTREAM: video / backlight: add two APIs for drivers to use
It is useful to get the backlight device's pointer and use it to set
backlight in some cases(the following patch will make use of it) so add
the two APIs and export them.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from commit f6a4790a54)

Change-Id: Ia7d06bf600f86ae25939b830e49f5057f48f992d
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Vladimir Zapolskiy
8c232cdec7 UPSTREAM: backlight: pwm_bl: Free PWM requested by legacy API on error path
If pwm is requested by legacy pwm_request() and if the following
backlight_device_register() call fails, add pwm_free() clean-up.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
(cherry picked from commit 60d613d6ae)

Change-Id: I7fc9742e69aacbe3f7cef1c56bbd35b4ca72720e
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Philipp Zabel
9b2f443b1a UPSTREAM: backlight: pwm_bl: Fix broken PWM backlight for non-dt platforms
Commit ee65ad0e2a9e ("backlight: pwm_bl: Avoid backlight flicker when
probed from DT") tries to dereference the device of_node pointer
unconditionally, causing a NULL pointer dereference on non-dt platforms.
Fix it by replacing the phandle variable with a node variable and
by checking that for NULL before dereferencing it.

Reported-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
(cherry picked from commit 8777078015)

Change-Id: If98d57968b7ae64164ae4d5995c8bf3007a35c0c
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Philipp Zabel
ccbd3bdde8 UPSTREAM: backlight: pwm_bl: Avoid backlight flicker when probed from DT
If the driver is probed from the device tree, and there is a phandle
property set on it, and the enable GPIO is already configured as output,
and the backlight is currently disabled, keep it disabled.
If all these conditions are met, assume there will be some other driver
that can enable the backlight at the appropriate time.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
(cherry picked from commit 3698d7e7d2)

Change-Id: I76012aae7f546b0189c879283988d7c098f23410
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Thierry Reding
5818f819cc UPSTREAM: pwm: Use kcalloc() instead of kzalloc()
kcalloc() should be preferred for allocations of arrays over kzalloc()
with multiplication.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 2907f8abb7)

Change-Id: Ifa4619bcd5c0869e516ae7765bab7515b299c533
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Thierry Reding
4079e6a2d2 UPSTREAM: pwm: Add missing newline
checkpatch requires that declarations be separated from code by a blank
line. Add one for readability and to silence the warning.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 83a98864ff)

Change-Id: I1e59599b099fe6b4d29e0f39225f8e18ce7c139e
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
e82fc9af20 UPSTREAM: pwm: Introduce the pwm_args concept
Currently the PWM core mixes the current PWM state with the per-platform
reference config (specified through the PWM lookup table, DT definition
or directly hardcoded in PWM drivers).

Create a struct pwm_args to store this reference configuration, so that
PWM users can differentiate between the current and reference
configurations.

Patch all places where pwm->args should be initialized. We keep the
pwm_set_polarity/period() calls until all PWM users are patched to use
pwm_args instead of pwm_get_period/polarity().

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

(cherry picked from commit e39c0df1be)

Change-Id: Id9ec0898d92d7049813c32acbd909103e949c846
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Jon Hunter
9f7ad83534 UPSTREAM: regulator: core: Add early supply resolution for regulators
The call to set_machine_constraints() in regulator_register(), will
attempt to get the voltage for the regulator. If a regulator is in
bypass will fail to get the voltage (ie. it's bypass voltage) and
hence register the regulator, because the supply for the regulator has
not been resolved yet.

To fix this, add a call to regulator_resolve_supply() before we call
set_machine_constraints(). If the call to regulator_resolve_supply()
fails, rather than returning an error at this point, allow the
registration of the regulator to continue because for some regulators
resolving the supply at this point may not be necessary and it will be
resolved later as more regulators are added. Furthermore, if the supply
is still not resolved for a bypassed regulator, this will be detected
when we attempt to get the voltage for the regulator and an error will
be propagated at this point.

If a bypassed regulator does not have a supply when we attempt to get
the voltage, rather than returing -EINVAL, return -EPROBE_DEFER instead
to allow the registration of the regulator to be deferred and tried
again later.

Please note that regulator_resolve_supply() will call
regulator_dev_lookup() which may acquire the regulator_list_mutex. To
avoid any deadlocks we cannot hold the regulator_list_mutex when calling
regulator_resolve_supply(). Therefore, rather than holding the lock
around a large portion of the registration code, just hold the lock when
aquiring any GPIOs and setting up supplies because these sections may
add entries to the regulator_map_list and regulator_ena_gpio_list,
respectively.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 45389c4752)

Change-Id: I9a0fa34c92b3326b9563672b74b5651cfd3a96f8
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
WEN Pingbo
0b97d6af04 UPSTREAM: regulator: refactor valid_ops_mask checking code
To make the code more compat and centralized, this patch add a
unified function - regulator_ops_is_valid. So we can add
some extra checking code easily later.

Signed-off-by: WEN Pingbo <pingbo.wen@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 8a34e979f6)

Change-Id: Ib3ffc949004c71abe3b75b4e0ffaf2e303f00d22
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Jon Hunter
14b8d1e030 UPSTREAM: regulator: helpers: Ensure bypass register field matches ON value
When checking bypass state for a regulator, we check to see if any bits
in the bypass mask are set. For most cases this is fine because there is
typically, only a single bit used to determine if the regulator is in
bypass. However, for some regulators, such as LDO6 on AS3722, the bypass
state is indicate by a value rather than a single bit. Therefore, when
checking the bypass state, check that the bypass field matches the ON
value.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit dd1a571dae)

Change-Id: Ic9f9ee919969cc744be7e7c94729ee7ab9e0e7a1
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Jon Hunter
e322305bba UPSTREAM: regulator: core: Move registration of regulator device
The public functions to acquire a regulator, such as regulator_get(),
internally look-up the regulator from the list of regulators that have
been registered with the regulator device class. The registration of
a new regulator with the regulator device class happens before the
regulator has been completely setup. Therefore, it is possible that
the regulator could be acquired before it has been setup successfully.
To avoid this move the device registration of the regulator to the end
of the regulator setup and update the error exit path accordingly.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit c438b9d017)

Change-Id: I9b33820c1ea748fdf5ccfb8949775b753af4a848
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Jon Hunter
2ba368178b UPSTREAM: regulator: core: Clear the supply pointer if enabling fails
During the resolution of a regulator's supply, we may attempt to enable
the supply if the regulator itself is already enabled. If enabling the
supply fails, then we will call _regulator_put() for the supply.
However, the pointer to the supply has not been cleared for the
regulator and this will cause a crash if we then unregister the
regulator and attempt to call regulator_put() a second time for the
supply. Fix this by clearing the supply pointer if enabling the supply
after fails when resolving the supply for a regulator.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 8e5356a736)

Change-Id: I3e83852db8c624fdd5b6c0bcab42c07289501a58
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Jon Hunter
faf68e977e UPSTREAM: regulator: core: Don't terminate supply resolution early
The function regulator_register_resolve_supply() is called from the
context of class_for_each_dev() (during the regulator registration) to
resolve any supplies added. regulator_register_resolve_supply() will
return an error if a regulator's supply cannot be resolved and this will
terminate the loop in class_for_each_dev(). This means that we will not
attempt to resolve any other supplies after one has failed. Hence, this
may delay the resolution of other regulator supplies until the failing
one itself can be resolved.

Rather than terminating the loop early, don't return an error code and
keep attempting to resolve any other supplies for regulators that have
been registered.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 7ddede6a58)

Change-Id: I92644a3c2006476440f0eeca2e4a9717743b13b9
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Richard Fitzgerald
2c0da078a7 UPSTREAM: regulator: core: Add debugfs to show constraint flags
There are debugfs entries for voltage and current, but not for
the constraint flags. It's useful for debugging to be able to
see what these flags are so this patch adds a new debugfs file.
We can't use debugfs_create_bool for this because the flags are
bitfields, so as this needs a special read callback they have been
collected into a single file that lists all the flags.

Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 2d80a91b2f)

Change-Id: Ia3e78960204e34e004340e28b3a7f933aa457371
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Mark Brown
59ba6e0376 UPSTREAM: regulator: core: Fix locking of GPIO list on free
When we acquire a shareable enable GPIO on probe we do so with the
regulator_list_mutex held.  However when we release the GPIOs we do this
immediately after dropping the mutex meaning that the list could become
corrupted.  Move the release into the locked region to avoid this.

Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 2c0a303a12)

Change-Id: I27a96e1b5ff3034fa068bda5436a479e01e5a61b
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00
Boris Brezillon
286d645c52 UPSTREAM: regulator: reorder initialization steps in regulator_register()
device_register() is calling ->get_voltage() as part of it's sysfs attribute
initialization process, and this functions might need to know the regulator
constraints to return a valid value.
This is at least true for the pwm regulator driver (when operating in
continuous mode) which needs to know the minimum and maximum voltage values
to calculate the current voltage:

min_uV + (((max_uV - min_uV) * dutycycle) / 100);

Move device_register() after set_machine_constraints() to make sure those
constraints are correctly initialized when ->get_voltage() is called.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reported-by: Stephen Barber <smbarber@chromium.org>
Tested-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 469b640e4f)

Change-Id: I83c95e5baef0501876d19f1e2e7a7e3af8631b1f
Signed-off-by: David Wu <david.wu@rock-chips.com>
2017-03-06 18:28:40 +08:00