Commit Graph

269 Commits

Author SHA1 Message Date
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
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
Geert Uytterhoeven
70145f8713 pwm: Fix uninitialized warnings in pwm_get()
With some versions of gcc (e.g. 4.1.2):

drivers/pwm/core.c: In function ‘pwm_get’:
drivers/pwm/core.c:610: warning: ‘polarity’ may be used uninitialized in this function
drivers/pwm/core.c:609: warning: ‘period’ may be used uninitialized in this function

While these are false positives, we can get rid of them by refactoring
the code to store a pointer to the best match, as suggested before by
Thierry Reding. This does require moving the mutex_unlock() down.

Fixes: d717ea73e3 ("pwm: Fix period and polarity in pwm_get() for non-perfect matches")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-29 10:18:19 +02:00
Doug Anderson
7264354c0c pwm: rockchip: Allow polarity invert on rk3288
The rk3288 has the ability to invert the polarity of the PWM.  Let's
enable that ability.  Note that this increases pwm_cells to 3 for
rk3288.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Caesar Wang <caesar.wang@rock-chips.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-26 10:44:08 +02:00
Liu Ying
137fd45ffe pwm: imx: Avoid sample FIFO overflow for i.MX PWM version2
The i.MX PWM version2 is embedded in several i.MX SoCs, such as i.MX27,
i.MX51 and i.MX6SL.  There is a 4-word (16 bit) sample FIFO in this IP.
Each FIFO slot determines the duty period of a PWM waveform in one full
cycle.  The IP spec mentions that we should not write a fourth sample
because the FIFO will become full and triggers a FIFO write error (FWE)
which will prevent the PWM from starting once it is enabled.  In order
to avoid any sample FIFO overflow issue, this patch clears all sample
FIFO by doing software reset in the configuration hook when the
controller is disabled or waits for a full PWM cycle to get a
relinquished FIFO slot when the controller is enabled and the FIFO is
fully loaded.

The FIFO overflow issue can be reproduced by the following commands on
the i.MX6SL EVK platform, assuming we use PWM2 for the debug LED which
is driven by the pin HSIC_STROBE and the maximal brightness is 255.

	echo 0   > /sys/class/leds/user/brightness
	echo 0   > /sys/class/leds/user/brightness
	echo 0   > /sys/class/leds/user/brightness
	echo 0   > /sys/class/leds/user/brightness
	echo 255 > /sys/class/leds/user/brightness

Here, FWE happens (PWMSR register reads 0x58) and the LED can not be
lighten.

Another way to reproduce the FIFO overflow issue is to run this script:

	while true;
		do echo 255 > /sys/class/leds/user/brightness;
	done

Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawn.guo@freescale.com>
Cc: Lothar Waßmann <LW@KARO-electronics.de>
Cc: linux-pwm@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
Acked-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-25 15:46:42 +02:00
Liu Ying
40f260c2ce pwm: imx: Cleanup indentation for register definitions
This patch contains no logic change to cleanup indentation for register
definitions only.

Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawn.guo@freescale.com>
Cc: Lothar Waßmann <LW@KARO-electronics.de>
Cc: linux-pwm@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
Acked-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-25 15:46:36 +02:00
Liu Ying
bd59bdc898 pwm: imx: Fix the macro MX3_PWMCR_PRESCALER(x) definition
This patch adds missing parentheses around the argument of the macro
MX3_PWMCR_PRESCALER(x) to avoid any potential macro expansion issue.

Reported-by: Lothar Waßmann <LW@KARO-electronics.de>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawn.guo@freescale.com>
Cc: Lothar Waßmann <LW@KARO-electronics.de>
Cc: linux-pwm@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
Acked-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-25 15:46:28 +02:00
Xiubo Li
533acc0e8d pwm: Fix possible ZERO_SIZE_PTR pointer dereferencing error.
Since we cannot make sure the 'chip->npwm' will always be none zero here,
and then if either equal to zero, the kzalloc() will return ZERO_SIZE_PTR,
which equals to ((void *)16).

So this patch fix this with just doing the zero check before calling kzalloc().

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-25 14:38:12 +02:00
Andy Shevchenko
ad16202de8 pwm: lpss: make it buildable only on X86
There is no sign of this IP block on non-x86 architectures and rather will not
be. Thus, make this explicit by applying a direct dependency to X86.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-25 11:46:37 +02:00
Julia Lawall
b2b7adeb21 pwm: lpss: use c99 initializers in structures
Use c99 initializers for structures.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@decl@
identifier i1,fld;
type T;
field list[n] fs;
@@

struct i1 {
 fs
 T fld;
 ...};

@bad@
identifier decl.i1,i2;
expression e;
initializer list[decl.n] is;
@@

struct i1 i2 = { is,
+ .fld = e
- e
 ,...};
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
[thierry.reding: rebased and applied same fix for Braswell]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-25 11:45:34 +02:00
Thierry Reding
e0c86a3b63 pwm: lpss: Fix build failure on PowerPC
An x86 build seems to pull in the linux/io.h include indirectly. On
PowerPC that doesn't happen and the build breaks due to the readl() and
writel() functions not being declared. Fix this by explicitly including
linux/io.h.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-23 00:25:52 +02:00
Andy Shevchenko
90927fe9a0 pwm: lpss: pci: Move to use pcim_enable_device()
Let's use managed functions for this driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-23 00:25:51 +02:00
Andy Shevchenko
c558e39e14 pwm: lpss: Properly split driver to parts
The driver consists of core, PCI, and platform parts. It would be better
to split them into separate files.

The platform driver is now called pwm-lpss-platform. Thus, previously
set CONFIG_PWM_LPSS=m is not enough to build it. But we are on the safe
side since it seems no one from outside Intel is using it for now.

While here, move to use macros module_pci_driver() and
module_platform_driver().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
[thierry.reding: change select to depends on PWM_LPSS, cleanup]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-23 00:25:47 +02:00
Alan Cox
373c57829a pwm: lpss: Add ACPI and PCI IDs for Intel Braswell
This is pretty much the same as Baytrail PWM. Only difference is that the
input clock runs on different frequency.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-22 11:52:30 +02:00
Fabio Estevam
00018a8ae5 pwm: fsl-ftm: Select REGMAP_MMIO
Commit 42fa98a9c3 ("pwm: fsl-ftm: Convert to direct regmap API usage")
introduced the following error when REGMAP_MMIO=n:

drivers/built-in.o: In function `fsl_pwm_probe':
>> pwm-fsl-ftm.c:(.text+0xd7d7): undefined reference to `devm_regmap_init_mmio_clk'

Select select REGMAP_MMIO in order to fix this error.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-22 10:17:01 +02:00
Xiubo Li
42fa98a9c3 pwm: fsl-ftm: Convert to direct regmap API usage
The regmap core supports different endian modes for devices. This patch
convert to direct regmap API usage, preparing to support big endianness
for LS1 SoC.

Using the regmap framework it will be easy to support devices that only
differ in endianness with the same device driver.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-20 10:10:12 +02:00
Xiubo Li
cd6d92d2aa pwm: fsl-ftm: Clean up the code
This patch intends to prepare for converting to direct regmap API usage.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-20 10:09:54 +02:00
Geert Uytterhoeven
d717ea73e3 pwm: Fix period and polarity in pwm_get() for non-perfect matches
If pwm_get() finds a look-up entry with a perfect match (both dev_id and
con_id match), the loop is aborted, and "p" still points to the correct
struct pwm_lookup.

If only an entry with a matching dev_id or con_id is found, the loop
terminates after traversing the whole list, and "p" now points to
arbitrary memory, not part of the pwm_lookup list.
Then pwm_set_period() and pwm_set_polarity() will set random values for
period resp. polarity.

To fix this, save period and polarity when finding a new best match,
just like is done for chip (for the provider) and index.

This fixes the LCD backlight on r8a7740/armadillo-legacy, which was fed
period 0 and polarity -1068821144 instead of 33333 resp. 1.

Fixes: 3796ce1d4d ("pwm: add period and polarity to struct pwm_lookup")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: stable@vger.kernel.org
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-18 10:58:43 +02:00
Linus Torvalds
34b20e6df6 pwm: Changes for v3.17-rc1
The set of changes for this merge window contains two new drivers: one
 for Rockchip SoCs and another for STMicroelectronics STiH4xx SoCs. The
 remainder of the changes are the usual small cleanups such as removing
 redundant OOM messages, signalling that a PWM chip's operations can
 sleep and removing an unneeded dependency.
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Merge tag 'pwm/for-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm changes from Thierry Reding:
 "The set of changes for this merge window contains two new drivers: one
  for Rockchip SoCs and another for STMicroelectronics STiH4xx SoCs.

  The remainder of the changes are the usual small cleanups such as
  removing redundant OOM messages, signalling that a PWM chip's
  operations can sleep and removing an unneeded dependency"

* tag 'pwm/for-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: rockchip: Added to support for RK3288 SoC
  pwm: rockchip: document RK3288 SoC compatible
  pwm: sti: Remove PWM period table
  pwm: sti: Sync between enable/disable calls
  pwm: sti: Ensure same period values for all channels
  pwm: sti: Fix PWM prescaler handling
  pwm: sti: Supply Device Tree binding documentation for ST's PWM IP
  pwm: sti: Add new driver for ST's PWM IP
  pwm: imx: set can_sleep flag for imx_pwm
  pwm: lpss: remove dependency on clk framework
  pwm: pwm-tipwmss: remove unnecessary OOM messages
  pwm: rockchip: document device tree bindings
  pwm: add Rockchip SoC PWM support
2014-08-08 18:06:29 -07:00
Caesar Wang
f630629908 pwm: rockchip: Added to support for RK3288 SoC
This patch added to support the PWM controller found on
RK3288 SoC.

Signed-off-by: Caesar Wang <caesar.wang@rock-chips.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-08 13:12:47 +02:00
Ajit Pal Singh
3aacd3e187 pwm: sti: Remove PWM period table
Removes the PWM period table. Instead the prescaler is computed
from the period value passed in the config() function.

Signed-off-by: Ajit Pal Singh <ajitpal.singh@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-08 13:12:46 +02:00
Ajit Pal Singh
6ad6b838e1 pwm: sti: Sync between enable/disable calls
ST PWM IP has a common enable/disable control for all the PWM
channels on a PWM cell. Disables PWM output on the PWM HW only
when disable is called for the last channel.

Signed-off-by: Ajit Pal Singh <ajitpal.singh@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-08 13:12:45 +02:00
Ajit Pal Singh
5165166e8a pwm: sti: Ensure same period values for all channels
ST PWM IP shares the same clock prescaler across all the PWM
channels. Hence configuration requests which change the period
will affect all the channels. Do not allow period changes which
will stomp period settings of the already configured channels.

Signed-off-by: Ajit Pal Singh <ajitpal.singh@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-08 13:12:45 +02:00
Ajit Pal Singh
bf9cc80b6c pwm: sti: Fix PWM prescaler handling
This patch fixes the pwm driver to write the complete 8 bits of
the prescaler value to the PWM Control register.

Signed-off-by: Ajit Pal Singh <ajitpal.singh@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-08-08 13:12:40 +02:00