Commit Graph

291 Commits

Author SHA1 Message Date
Linus Torvalds 82278fc079 pwm: Changes for v4.3-rc1
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).
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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
2015-09-09 10:55:32 -07:00
Josh Wu 7a59382018 ARM: at91: pwm: atmel-hlcdc: Add at91sam9n12 errata
The errata for HLCDC PWM of at91sam9n12 are the same as for at91sam9x5.

Signed-off-by: Josh Wu <josh.wu@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-09-09 15:16:01 +02:00
Ariel D'Alessandro 841e6f90bb pwm: NXP LPC18xx PWM/SCT driver
This commit adds support for NXP LPC18xx PWM/SCT.

NXP LPC SoCs family, which includes LPC18xx/LPC43xx, provides a State
Configurable Timer (SCT) which can be configured as a Pulse Width
Modulator. Other SoCs in that family may share the same hardware.

The PWM supports a total of 16 channels, but only 15 can be simultaneously
requested. There's only one period, global to all the channels, thus PWM
driver will refuse setting different values to it, unless there's only one
channel requested.

Signed-off-by: Ariel D'Alessandro <ariel@vanguardiasur.com.ar>
[thierry.reding@gmail.com: remove excessive padding of fields]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-09-09 15:00:33 +02:00
Clemens Gruber 01ec847200 pwm-pca9685: Support changing the output frequency
Previously, period_ns and duty_ns were only used to determine the
ratio of ON and OFF time, the default frequency of 200 Hz was never
changed.
The PCA9685 however is capable of changing the PWM output frequency,
which is expected when changing the period.

This patch configures the prescaler accordingly, using the formula
and notes provided in the PCA9685 datasheet.
Bounds checking for the minimum and maximum frequencies, last updated
in revision v.4 of said datasheet, is also added.

The prescaler is only touched if the period changed, because we have to
put the chip into sleep mode to unlock the prescale register.
If it is changed, the PWM output frequency changes for all outputs,
because there is one prescaler per chip. This is documented in the
PCA9685 datasheet and in the comments.

If the duty cycle is not changed at the same time as the period, then
we restart the PWM output using the duty cycle to period ratio from
before the period change.
When using LEDs for example, previously set brightness levels stay the
same when the frequency changes.

Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-08-17 16:35:46 +02:00
Clemens Gruber 4a627b52e4 pwm-pca9685: Fix several driver bugs
Problems:
- When duty_ns == period_ns, the full OFF bit was not cleared and the
  PWM output of the PCA9685 stayed off.
- When duty_ns == period_ns and the catch-all channel was used, the
  ALL_LED_OFF_L register was not cleared.
- The full ON bit was not cleared when setting the OFF time, therefore
  the exact OFF time was ignored when setting a duty_ns < period_ns

Solution: Clear both OFF registers when setting full ON and clear the
full ON bit when changing the OFF registers.

Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-08-17 16:35:13 +02:00
Jonathan Richardson fe0aea7978 pwm: kona: Modify settings application sequence
Update the driver so that settings are applied in accordance with the
most recent version of the hardware spec.  The revised sequence clears
the trigger bit, waits 400ns, writes settings, sets the trigger bit,
and waits another 400ns.  This corrects an issue where occasionally a
requested change was not properly reflected in the PWM output.

Reviewed-by: Arun Ramamurthy <arunrama@broadcom.com>
Reviewed-by: Scott Branden <sbranden@broadcom.com>
Tested-by: Scott Branden <sbranden@broadcom.com>
Reviewed-by: Tim Kryger <tim.kryger@gmail.com>
Signed-off-by: Jonathan Richardson <jonathar@broadcom.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-08-17 16:19:41 +02:00
Krzysztof Kozlowski 09c14459f2 pwm: pca9685: Drop owner assignment
i2c_driver does not need to set an owner because i2c_register_driver()
will set it.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-08-17 15:56:01 +02:00
Thierry Reding 0488380276 pwm: Clean up kerneldoc
Clean up kerneldoc in preparation for including the PWM documentation in
DocBook.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-08-17 15:40:20 +02:00
Thierry Reding 6bc7064a69 pwm: Remove useless whitespace
Remove useless tabs used for padding in structure definitions as well as
some blank lines.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-08-17 15:40:19 +02:00
Thierry Reding 412820dd53 pwm: sysfs: Remove unnecessary padding
Padding initializers so that assignment operators align is bound to lead
to inconsistencies or churn. Single spaces around the assignment is just
fine.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-07-27 12:03:38 +02:00
Thierry Reding 5a063d87e9 pwm: sysfs: Properly convert from enum to string
The current code will check for polarity in a boolean way. While it is
correct that polarity is either normal or inversed, make it more obvious
that it's an enumeration by using a switch statement and explicit
matches on the enumeration values.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-07-27 12:03:37 +02:00
Shobhit Kumar a3f37a104b pwm: crc: Add Crystalcove (CRC) PWM driver
The Crystalcove PMIC provides three PWM signals and this driver exports
one of them on the BYT platform which is used to control backlight for
DSI panel. This is platform device implementation of the drivers/mfd
cell device for CRC PMIC.

CC: Samuel Ortiz <sameo@linux.intel.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com>
Reviewed-by: Varka Bhadram <varkabhadram@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-07-21 09:22:23 +02:00
Boris Brezillon 15da7b5001 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>
2015-07-20 09:53:22 +02:00
Boris Brezillon 5c31252c4a pwm: Add the pwm_is_enabled() helper
Some PWM drivers are testing the PWMF_ENABLED flag. Create a helper
function to hide the logic behind enabled test. This will allow us to
smoothly move from the current approach to an atomic PWM update
approach.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-07-20 09:46:06 +02:00
Linus Torvalds c70c5fb2b9 pwm: Changes for v4.2-rc1
This has a couple of fixes for Atmel, Samsung and Broadcom drivers. Some
 preparatory patches for more upcoming Intel work is included as well.
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Merge tag 'pwm/for-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "This has a couple of fixes for Atmel, Samsung and Broadcom drivers.

  Some preparatory patches for more upcoming Intel work is included as
  well"

* tag 'pwm/for-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: lpss: pci: Add support for Broxton platform
  pwm: bcm-kona: Don't set polarity in probe
  pwm: Add pwmchip_add_with_polarity() API
  pwm: atmel: Fix incorrect CDTY value after disabling
  pwm: atmel: Fix incorrect CDTY value after enabling
  pwm: samsung: Use MODULE_DEVICE_TABLE() to include OF modalias
  pwm: Add support to remove registered consumer lookup tables
2015-06-23 13:32:38 -07:00
Qipeng Zha 361c1066c9 pwm: lpss: pci: Add support for Broxton platform
Add PCI device IDs for Broxton platform.

Signed-off-by: Qipeng Zha <qipeng.zha@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-06-12 12:46:50 +02:00
Arun Ramamurthy e23db65f3d pwm: bcm-kona: Don't set polarity in probe
Omit setting the polarity to normal during probe and instead use the new
pwmchip_add_with_polarity() function to register a PWM chip with inverse
polarity by default for all channels to reflect the hardware default.

Signed-off-by: Arun Ramamurthy <arunrama@broadcom.com>
Reviewed-by: Ray Jui <rjui@broadcom.com>
Signed-off-by: Scott Branden <sbranden@broadcom.com>
Signed-off-by: Tim Kryger <tim.kryger@gmail.com>
Signed-off-by: Jonathan Richardson <jonathar@broadcom.com>
[thierry.reding@gmail.com: use pwmchip_add_with_polarity()]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-06-12 11:42:33 +02:00
Tim Kryger b6a00fae97 pwm: Add pwmchip_add_with_polarity() API
Add a new function to register a PWM chip with channels that have their
initial polarity as specified by an additional parameter. This benefits
drivers of controllers that by default operate with inversed polarity
by removing the need to modify the polarity during initialization.

Signed-off-by: Tim Kryger <tim.kryger@gmail.com>
Signed-off-by: Jonathan Richardson <jonathar@broadcom.com>
[thierry.reding@gmail.com: export pwmchip_add_with_polarity()]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-06-12 11:36:30 +02:00
Alexandre Belloni 472ac3dcac pwm: atmel: Fix incorrect CDTY value after disabling
pwm-leds calls .config() and .disable() in a row. This exhibits that it
may happen that the channel gets disabled before CDTY has been updated
with CUPD. The issue gets quite worse with long periods. So, ensure that
at least one period has past before disabling the channel by polling
ISR.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Tested-by: Gaël PORTAY <gael.portay@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-06-12 11:16:12 +02:00
Alexandre Belloni 4c027f7ba8 pwm: atmel: Fix incorrect CDTY value after enabling
CUPD is not flushed before enabling the channel so it will update
CDTY/CPRD just after one period. So we always set CUPD, even when the
channel is not enabled.

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>
2015-06-12 11:12:20 +02:00
Javier Martinez Canillas cccb94543c pwm: samsung: Use MODULE_DEVICE_TABLE() to include OF modalias
If the pwm-samsung driver is built as a module, modalias information is
not filled so the module is not autoloaded. Use the MODULE_DEVICE_TABLE()
macro to export the OF device ID so the module contains that information.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-05-21 15:56:53 +02:00
Naidu Tellapati 1e70897d0e pwm: img: Impose upper and lower timebase steps value
The PWM hardware on Pistachio platform has a maximum timebase steps
value to 255. To fix it, let's introduce a compatible-specific
data structure to contain the SoC-specific details and use it to
specify a maximum timebase.

Also, let's limit the minimum timebase to 16 steps, to allow a sane
range of duty cycle steps.

Fixes: 277bb6a29e ("pwm: Imagination Technologies PWM DAC driver")
Signed-off-by: Naidu Tellapati <naidu.tellapati@imgtec.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-05-19 16:07:40 +02:00
Shobhit Kumar efb0de55b6 pwm: Add support to remove registered consumer lookup tables
In case some drivers are unloading, they can remove lookup tables which
they had registered during their load time to avoid redundant entries if
loaded again.

CC: Samuel Ortiz <sameo@linux.intel.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-05-06 14:19:35 +02:00
Shobhit Kumar c264f1110d pwm: Remove __init initializer for pwm_add_table()
For platforms that don't support DT, some early MFD modules can register
lookup tables. Remove the __init annotation so that this works. This is
similar to gpio_add_lookup_table() which allows late additions.

CC: Samuel Ortiz <sameo@linux.intel.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-04-23 14:50:52 +02:00
Sjoerd Simons 4a1c683c98 pwm: samsung: Fix output race on disabling
When disabling the Samsung PWM the output state remains at the level it
was at the end of a PWM cycle. In other words, calling pwm_disable()
when at 100% duty cycle will keep the output active, while at all other
settings the output will go/stay inactive. On top of that the Samsung
PWM settings are double-buffered, which means the new settings only get
applied at the start of a new PWM cycle.

This results in a race if the PWM is at 100% duty cycle and a driver
calls:

  pwm_config(pwm, 0, period);
  pwm_disable(pwm);

In this case the PWMs output will unexpectedly stay active, unless a new
PWM cycle happened to start between the register writes in pwm_config()
and pwm_disable(). As far as I can tell this is a regression introduced
by 3bdf878, before that a call to pwm_config() would call
pwm_samsung_enable() which, while heavy-handed, made sure the expected
settings were live.

To resolve this, while not re-introducing the issues 3bdf878 (flickering
as the PWM got reset while in a PWM cycle) fixed, only force an update
of the settings when at 100% duty cycle, which shouldn't have any
noticeable effect on the output but is enough to ensure the behaviour is
as expected on disable.

Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Acked-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-03-27 13:06:47 +01:00
Gaetan Hug 24ccea1ce6 pwm: mxs: Fix period divider computation
The driver computes which clock divider it sould be using from the
requested period. This computation assumes that the link between the
register value and the actual divider value is raising 2 to the power of
the registry value.

    div = 1 << regvalue

This is true only for the first 5 values out of 8. Next values are 64,
256 and, 1024 - instead of 32, 64, 128.
This affects only the users requesting a period > 0.04369s.

Replace the computation with a look-up table.

Signed-off-by: Gaetan Hug <ghug@induct.be>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-03-11 13:11:16 +01:00
Nicolas Ferre 054d3e1f9a pwm: atmel-hlcdc: Add errata handling for sama5d4
sama5d4 SoC also has an errata on the HLCDC PWM. It is the same as the
sama5d3 that is forbidding the use of div1 prescaler.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-03-11 11:59:54 +01:00
Krzysztof Kozlowski c456fbb2b2 pwm: pca9685: Constify struct regmap_config
The regmap_config struct may be const because it is not modified by the
driver and regmap_init() accepts pointer to const.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-03-11 10:25:13 +01:00
Thierry Reding b65af27ad8 pwm: tegra: Use NSEC_PER_SEC
Instead of using the literal value for the number of nanoseconds per
second, use the macro instead to increase readability.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-02-18 08:40:29 +01:00
Markus Elfring 8d6cc07385 pwm: Remove unnecessary check before of_node_put()
The of_node_put() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-02-03 12:56:54 +01:00
Naidu Tellapati 277bb6a29e pwm: Imagination Technologies PWM DAC driver
The Pistachio SOC from Imagination Technologies includes a Pulse Width
Modulation DAC which produces 1 to 4 digital bit-outputs which represent
digital waveforms. These PWM outputs are primarily in charge of controlling
backlight LED devices.

Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Naidu Tellapati <Naidu.Tellapati@imgtec.com>
Signed-off-by: Sai Masarapu <Sai.Masarapu@imgtec.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Reviewed-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
[thierry.reding: fixup license header as discussed on list]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-01-30 12:16:04 +01:00
Ajit Pal Singh cd264b6a65 pwm: sti: Maintain a bitmap of configured devices
This patch introduces a bitmap which is used to keep track of the
pwm channels which have been configured in a pwm chip.

The method used earlier to find the number of configured channels,
was to count the pwmdevices with PWMF_REQUESTED field set
and period value configured. This was not correct and failed
when of_pwm_get()/pwm_get() and then pwm_config() was used.

Signed-off-by: Ajit Pal Singh <ajitpal.singh@st.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-01-30 12:16:03 +01:00
Alexandre Belloni 09853ce7bc pwm: Add Allwinner SoC support
This adds a generic PWM framework driver for the PWM controller
found on Allwinner SoCs.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-01-30 12:16:01 +01:00
Boris BREZILLON df6922adec pwm: atmel-hlcdc: Prevent division by zero
The slow and system clock should never return a rate of zero, but this
might happen if the clocks property defined in the DT is referencing the
wrong clocks.

Prevent any division by zero from happening by testing the clk_freq
value before calling do_div().

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-01-30 12:16:00 +01:00
Thierry Reding d2048c4915 pwm: atmel-hlcdc: Depend on HAVE_CLK
The include/linux/clk.h header defines dummy implementations for the
various clk_*() functions if HAVE_CLK is not selected to improve build
coverage in randconfig builds.

The dummy implementation of clk_get_rate() returns 0, which causes the
Atmel HLCDC PWM driver's atmel_hlcdc_pwm_config() implementation to end
up calling:

	do_div(clk_period_ns, 0)

On x86, do_div(n, base) will end up evaluating to this:

	n >>= ilog2(base)

with base = 0, the implementation of ilog2() will call ____ilog2_NaN(),
which is purposely undefined and results in a linker failure:

	ERROR: "____ilog2_NaN" [drivers/pwm/pwm-atmel-hlcdc.ko] undefined!

The implementation of do_div() checks that base is a power of 2 before
calling ilog2(). The compiler doesn't optimize this away, presumably
because is_power_of_2() is an inline function and the compiler doesn't
or can't inspect it closely enough. ilog2() being a macro it still ends
up generating the ____ilog2_NaN() because of the constant 0.

The root of the problem is that the driver really should be checking
before possibly dividing by zero. That should eventually be fixed, but
for now just assume that the clock runs at a sensible frequency when
available.

Reported-by: Jim Davis <jim.epost@gmail.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-01-30 12:15:58 +01:00
Linus Torvalds 0b4954c469 pwm: Changes for v3.19-rc1
There are two new drivers, one for the BCM2835 (Raspberry Pi) and one
 used in conjunction with the LCD controller on various Atmel SoCs. The
 Samsung PWM driver can now be built for 64-bit ARM (Exynos7).
 
 A couple of fixes have been applied to the FTM PWM driver and system
 sleep support was added.
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Merge tag 'pwm/for-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "There are two new drivers, one for the BCM2835 (Raspberry Pi) and one
  used in conjunction with the LCD controller on various Atmel SoCs.
  The Samsung PWM driver can now be built for 64-bit ARM (Exynos7).

  A couple of fixes have been applied to the FTM PWM driver and system
  sleep support was added"

* tag 'pwm/for-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: atmel-hlcdc: add at91sam9x5 and sama5d3 errata handling
  pwm: ftm: Add Power Management support for FTM PWM
  pwm: ftm: Add regmap rbtree type cache support
  pwm: ftm: Correctly track usage count
  pwm: samsung: Allow Samsung PWM driver to be enabled on Exynos7
  pwm: add DT bindings documentation for atmel-hlcdc-pwm driver
  pwm: add support for atmel-hlcdc-pwm device
  pwm: Add BCM2835 PWM driver
2014-12-17 10:10:51 -08:00
Boris BREZILLON 39e046f2c1 pwm: atmel-hlcdc: add at91sam9x5 and sama5d3 errata handling
at91sam9x5 has an errata forbidding the use of slow clk as a clk source and
sama5d3 SoCs has another errata forbidding the use of div1 prescaler.

Take both of these erratas into account.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-12-04 11:32:36 +01:00
Xiubo Li 97d0b42e39 pwm: ftm: Add Power Management support for FTM PWM
Add PM support for FTM PWM driver using callback function suspend
and resume in .driver.pm of platform_driver.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-12-01 10:48:54 +01:00
Xiubo Li 49599cf6bb pwm: ftm: Add regmap rbtree type cache support
This patch is to prepare for adding PM support for FTM PWM driver using
callback function suspend and resume in .driver.pm of platform_driver.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-12-01 10:44:48 +01:00
Xiubo Li 8e6e765102 pwm: ftm: Correctly track usage count
No matter how many times the FTM PWM is enabled, the use_count will
always be one.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-12-01 10:43:45 +01:00
Abhilash Kesavan 06e4cb6b1d pwm: samsung: Allow Samsung PWM driver to be enabled on Exynos7
To re-use the existing PWM driver for 64-bit ARM based Exynos7 SoC, make
the driver depend on ARCH_EXYNOS along with PLAT_SAMSUNG.

Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-11-17 12:24:17 +01:00
Boris Brezillon 2b4984bef4 pwm: add support for atmel-hlcdc-pwm device
The HLCDC IP available in some Atmel SoCs (i.e. at91sam9x5, at91sam9n12
or sama5d3 families for instance) provides a PWM device.

This driver add support for a PWM chip exposing a single PWM device (which
will most likely be used to drive a backlight device).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Anthony Harivel <anthony.harivel@emtrion.de>
Tested-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-11-17 12:20:17 +01:00
Bart Tanghe e5a06dc5ac pwm: Add BCM2835 PWM driver
Add PWM driver for Broadcom BCM2835 processor (Raspberry Pi)

Signed-off-by: Bart Tanghe <bart.tanghe@thomasmore.be>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-11-17 12:20:13 +01:00
Greg Kroah-Hartman a8a93c6f99 Merge branch 'platform/remove_owner' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux into driver-core-next
Remove all .owner fields from platform drivers
2014-11-03 19:53:56 -08:00
Linus Torvalds 5b9c897252 pwm: Changes for v3.18-rc1
There are no new drivers here, only a couple of fixes all over the place.
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Merge tag 'pwm/for-3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm changes from Thierry Reding:
 "There are no new drivers here, only a couple of fixes all over the
  place"

* tag 'pwm/for-3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: Let PWM_CLPS711X depend on HAS_IOMEM
  pwm: atmel: Fix calculation of prescale value
  pwm: Fix uninitialized warnings in pwm_get()
  pwm: rockchip: Allow polarity invert on rk3288
  pwm: imx: Avoid sample FIFO overflow for i.MX PWM version2
  pwm: imx: Cleanup indentation for register definitions
  pwm: imx: Fix the macro MX3_PWMCR_PRESCALER(x) definition
  pwm: Fix possible ZERO_SIZE_PTR pointer dereferencing error.
  pwm: lpss: make it buildable only on X86
  pwm: lpss: use c99 initializers in structures
  pwm: lpss: Fix build failure on PowerPC
  pwm: lpss: pci: Move to use pcim_enable_device()
  pwm: lpss: Properly split driver to parts
  pwm: lpss: Add ACPI and PCI IDs for Intel Braswell
  pwm: fsl-ftm: Select REGMAP_MMIO
  pwm: fsl-ftm: Document 'big-endian' property
  pwm: fsl-ftm: Convert to direct regmap API usage
  pwm: fsl-ftm: Clean up the code
2014-10-21 08:17:43 -07:00
Wolfram Sang f05fae14a1 pwm: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:21:28 +02:00
Chen Gang dec02f98ae pwm: Let PWM_CLPS711X depend on HAS_IOMEM
PWM_CLPS711X needs HAS_IOMEM, so depend on it, the related error (with
allmodconfig under um):

    MODPOST 1205 modules
  ERROR: "devm_ioremap_resource" [drivers/pwm/pwm-clps711x.ko] undefined!
  ERROR: "devm_ioremap" [drivers/net/phy/mdio-bcm-unimac.ko] undefined!

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-10-20 09:39:44 +02:00
Nikolaus Voss e2e0897010 pwm: atmel: Fix calculation of prescale value
The prescale value used for calculating the period was incremented
afterwards, thus the resulting prescale value is by one too high.
This resulted in a PWM frequency only half as high as requested.

This patch moves the 64 bit division out of the prescale loop to
correct the above issue and make the calculation more efficient.

Signed-off-by: Nikolaus Voss <n.voss@weinmann-emt.de>
Tested-by: Bo Shen <voice.shen@atmel.com>
Acked-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-09-25 08:52:39 +02:00
Arnd Bergmann c40c4028f0 Second batch of AT91 cleanup for 3.18:
- Timer Counter (TC) fixup and cleanup:
   - fix segmentation fault when kexec-ing a kernel by masking
     TC interrupts at shutdown and probe time
   - use modern driver model: devm_*, probe function, sanitize IRQ request
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Merge tag 'at91-cleanup2' of git://github.com/at91linux/linux-at91 into next/cleanup

Pull "Second batch of AT91 cleanup for 3.18" from Nicolas Ferre:
- Timer Counter (TC) fixup and cleanup:
  - fix segmentation fault when kexec-ing a kernel by masking
    TC interrupts at shutdown and probe time
  - use modern driver model: devm_*, probe function, sanitize IRQ request

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

* tag 'at91-cleanup2' of git://github.com/at91linux/linux-at91:
  clocksource: tcb_clksrc: sanitize IRQ request
  ARM: at91/tclib: mask interruptions at shutdown and probe
  ARM: at91/tclib: move initialization from alloc to probe
  ARM: at91/tclib: prefer using of devm_* functions
2014-09-09 17:03:17 +02:00
Gaël PORTAY 4930d247af ARM: at91/tclib: move initialization from alloc to probe
Move resource retrieval from atmel_tc_alloc to tc_probe to avoid lately
reporting resource related issues when a TC block user request a TC block.

Moreover, resources retrieval are usually done in the probe function,
thus moving them add some consistency with other drivers.

Initialization is done once, ie not every time a tc block is requested.
If it fails, the device is not appended to the list of tc blocks.

Furhermore, the device id is retrieved at probe as well, avoiding parsing
DT every time the user requests of tc block.

Signed-off-by: Gaël PORTAY <gael.portay@gmail.com>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-09-08 10:54:03 +02:00