PWM channel data was set to NULL before freeing it. This caused the
following kernel warning while unexporting the channel. Set the channel
data to NULL after freeing it.
[ 70.495000] WARNING: CPU: 0 PID: 1 at drivers/base/devres.c:805 pwm_put+0x48/0x80()
[ 70.505000] Modules linked in:
[ 70.505000] CPU: 0 PID: 1 Comm: sh Not tainted 3.12.0-rc6-next-20131024-00012-gd4aec04-dirty #58
[ 70.515000] [<c0014ddc>] (unwind_backtrace+0x0/0xf4) from [<c0011784>] (show_stack+0x10/0x14)
[ 70.525000] [<c0011784>] (show_stack+0x10/0x14) from [<c03a3cbc>] (dump_stack+0x7c/0xb0)
[ 70.530000] [<c03a3cbc>] (dump_stack+0x7c/0xb0) from [<c001de68>] (warn_slowpath_common+0x6c/0x88)
[ 70.540000] [<c001de68>] (warn_slowpath_common+0x6c/0x88) from [<c001df20>] (warn_slowpath_null+0x1c/0x24)
[ 70.550000] [<c001df20>] (warn_slowpath_null+0x1c/0x24) from [<c01d1af8>] (pwm_put+0x48/0x80)
[ 70.560000] [<c01d1af8>] (pwm_put+0x48/0x80) from [<c01d21c8>] (pwm_unexport_store+0x94/0xac)
[ 70.565000] [<c01d21c8>] (pwm_unexport_store+0x94/0xac) from [<c010991c>] (sysfs_write_file+0x148/0x1d8)
[ 70.575000] [<c010991c>] (sysfs_write_file+0x148/0x1d8) from [<c00b2a80>] (vfs_write+0xb4/0x1a0)
[ 70.585000] [<c00b2a80>] (vfs_write+0xb4/0x1a0) from [<c00b3068>] (SyS_write+0x3c/0x78)
[ 70.595000] [<c00b3068>] (SyS_write+0x3c/0x78) from [<c000e2e0>] (ret_fast_syscall+0x0/0x30)
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Remove the non-standard EP93xx PWM driver in drivers/misc and add
a new driver for the PWM controllers on the EP93xx platform based
on the PWM framework.
These PWM controllers each support 1 PWM channel with programmable
duty cycle, frequency, and polarity inversion.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ryan Mallon <rmallon@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Since commit ab78029 (drivers/pinctrl: grab default handles from device core),
we can rely on device core for setting the default pins. Compile tested only.
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The data structure of_match_ptr() protects is always compiled in.
Hence of_match_ptr() is not needed.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The data structure of_match_ptr() protects is always compiled in.
Hence of_match_ptr() is not needed.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Alexandre Pereira da Silva <aletes.xgr@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The data structure of_match_ptr() protects is always compiled in.
Hence of_match_ptr() is not needed.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
'of_match_ptr' is defined in linux/of.h. Include it explicitly.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
'of_match_ptr' is defined in linux/of.h. Include it explicitly.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
'of_match_ptr' is defined in linux/of.h. Include it explicitly.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
'of_match_ptr' is defined in linux/of.h. Include it explicitly.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Use the the tcb counter width to compute the maximum time that can be
represented using the slow clock source instead of the static 16 bit width.
Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Clock source changes are never applied to the CMR register.
This may lead to wrong period/duty cycle configuration.
Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This branch contains code cleanups, moves and removals for 3.12.
There's a large number of various cleanups, and a nice net removal of
13500 lines of code.
Highlights worth mentioning are:
- A series of patches from Stephen Boyd removing the ARM local timer API.
- Move of Qualcomm MSM IOMMU code to drivers/iommu.
- Samsung PWM driver cleanups from Tomasz Figa, removing legacy PWM driver
and switching over to the drivers/pwm one.
- Removal of some unusued auto-generated headers for OMAP2+ (PRM/CM).
There's also a move of a header file out of include/linux/i2c/ to
platform_data, where it really belongs. It touches mostly ARM platform
code for include changes so we took it through our tree.
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Merge tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC cleanups from Olof Johansson:
"This branch contains code cleanups, moves and removals for 3.12.
There's a large number of various cleanups, and a nice net removal of
13500 lines of code.
Highlights worth mentioning are:
- A series of patches from Stephen Boyd removing the ARM local timer
API.
- Move of Qualcomm MSM IOMMU code to drivers/iommu.
- Samsung PWM driver cleanups from Tomasz Figa, removing legacy PWM
driver and switching over to the drivers/pwm one.
- Removal of some unusued auto-generated headers for OMAP2+ (PRM/CM).
There's also a move of a header file out of include/linux/i2c/ to
platform_data, where it really belongs. It touches mostly ARM
platform code for include changes so we took it through our tree"
* tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (83 commits)
ARM: OMAP2+: Add back the define for AM33XX_RST_GLOBAL_WARM_SW_MASK
gpio: (gpio-pca953x) move header to linux/platform_data/
arm: zynq: hotplug: Remove unreachable code
ARM: SAMSUNG: Remove unnecessary exynos4_default_sdhci*()
tegra: simplify use of devm_ioremap_resource
ARM: SAMSUNG: Remove plat/regs-timer.h header
ARM: SAMSUNG: Remove remaining uses of plat/regs-timer.h header
ARM: SAMSUNG: Remove pwm-clock infrastructure
ARM: SAMSUNG: Remove old PWM timer platform devices
pwm: Remove superseded pwm-samsung-legacy driver
ARM: SAMSUNG: Modify board files to use new PWM platform device
ARM: SAMSUNG: Rework private data handling in dev-backlight
pwm: Add new pwm-samsung driver
ARM: mach-mvebu: remove redundant DT parsing and validation
ARM: msm: Only compile io.c on platforms that use it
iommu/msm: Move mach includes to iommu directory
ARM: msm: Remove devices-iommu.c
ARM: msm: Move mach/board.h contents to common.h
ARM: msm: Migrate msm_timer to CLOCKSOURCE_OF_DECLARE
ARM: msm: Remove TMR and TMR0 static mappings
...
Commit 76abbdde2d
pwm: Add sysfs interface
causes a kernel oops due to a null pointer dereference on PXA platforms.
This happens because the class added by the patch is registered in a
subsys_initcall (initcall4), but the pxa pwm driver is registered in
arch_initcall (initcall3). If the class is not registered before the
driver probe function runs, the oops occurs in device_add() when the
uninitialized pointers in struct class are dereferenced. I don't see a
reason that the driver must be an arch_initcall, so this patch makes it
a regular module_platform_driver (initcall6), preventing the oops.
Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
ecap_pwm_save_context() and ecap_pwm_restore_context() are only used
when CONFIG_PM_SLEEP is selected.
drivers/pwm/pwm-tiecap.c:293:13: warning: 'ecap_pwm_save_context' defined but not used [-Wunused-function]
drivers/pwm/pwm-tiecap.c:302:13: warning: 'ecap_pwm_restore_context' defined but not used [-Wunused-function]
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Remove unneeded error handling on the result of a call to
platform_get_resource when the value is passed to devm_ioremap_resource.
Move the call to platform_get_resource adjacent to the call to
devm_ioremap_resource to make the connection between them more clear.
A simplified version of the semantic patch that makes this change is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
expression pdev,res,n,e,e1;
expression ret != 0;
identifier l;
@@
- res = platform_get_resource(pdev, IORESOURCE_MEM, n);
... when != res
- if (res == NULL) { ... \(goto l;\|return ret;\) }
... when != res
+ res = platform_get_resource(pdev, IORESOURCE_MEM, n);
e = devm_ioremap_resource(e1, res);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Specify DT bindings for the TPU PWM controller and add OF support to the
driver.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Don't redefine a PWM_SPEC_POLARITY macro with a value identical to
PWM_POLARITY_INVERTED, use the PWM DT macro directly.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
stmp_reset_block() may fail, so let's check its return value and
propagate it in the case of error.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This patch removes the now unused pwm-samsung-legacy driver, which was
replaced by new pwm-samsung driver.
Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Mark Brown <broonie@linaro.org>
Tested-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
This patch introduces new Samsung PWM driver, which is completely
rewritten to be multiplatform- and DeviceTree-aware.
In addition, remaining problems of old driver are fixed, such as:
- proper handling of hardware variants,
- synchronization on SMP systems,
- handling of boundary parameter values,
- hardware sharing with PWM clocksource driver,
- undefined state of PWM output after stopping PWM channel.
Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Mark Brown <broonie@linaro.org>
Tested-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
This patch renames the old pwm-samsung driver to pwm-samsung-legacy to
create place for the new, rewritten, DT-aware pwm-samsung driver.
Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Mark Brown <broonie@linaro.org>
Tested-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
The dev_attrs field of struct class is going away soon, dev_groups
should be used instead. This converts the PWM class code to use the
correct field.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Current code actually does not set MODE1_SLEEP bit because the new value for
bitmask (0x1) is wrong. To set MODE1_SLEEP bit, we should pass MODE1_SLEEP
as the new value for bitmask.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Reviewed-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This driver can be built as module, add MODULE_ALIAS to make module auto loading
work.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
In case of error, the function devm_ioremap_resource() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should
be replaced with IS_ERR().
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Reviewed-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The Timer Pulse Unit (TPU) is a 4-channels 16-bit timer used to generate
waveforms. This driver exposes PWM functions through the PWM API for
other drivers to use.
The code is loosely based on the leds-renesas-tpu driver by Magnus Damm
and the TPU PWM driver shipped in the Armadillo EVA 800 kernel sources.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Tested-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Add a simple sysfs interface to the generic PWM framework.
/sys/class/pwm/
`-- pwmchipN/ for each PWM chip
|-- export (w/o) ask the kernel to export a PWM channel
|-- npwm (r/o) number of PWM channels in this PWM chip
|-- pwmX/ for each exported PWM channel
| |-- duty_cycle (r/w) duty cycle (in nanoseconds)
| |-- enable (r/w) enable/disable PWM
| |-- period (r/w) period (in nanoseconds)
| `-- polarity (r/w) polarity of PWM (normal/inversed)
`-- unexport (w/o) return a PWM channel to the kernel
Based on work by Lars Poeschel.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Lars Poeschel <poeschel@lemonage.de>
Cc: Ryan Mallon <rmallon@gmail.com>
Cc: Rob Landley <rob@landley.net>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Some drivers don't set the .owner fields of the struct device_driver or
struct pwm_ops, which causes the module usage count to become wrong.
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Add pwm driver for the NXP pca9685 16 channel pwm-led controller.
The driver is really barebones at this stage. E.g. the OE' pin and
therefore the corresponding registers are not supported.
The driver was tested on a HW where this pin is tied to GND.
Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
[thierry.reding@gmail.com: style and whitespace cleanups]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Replace clk_enable/disable with clk_prepare_enable/disable_unprepare to
avoid common clk framework warnings.
Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The allocated object should be the size of what the pointer is pointing
to and not the size of the pointer itself.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Since commit ab78029 (drivers/pinctrl: grab default handles from device core),
we can rely on device core for handling pinctrl.
So remove devm_pinctrl_get_select_default() from the driver.
Cc: Thierry Reding <thierry.reding@avionic-design.de>
Cc: <linux-kernel@vger.kernel.org>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Stephen Warren <swarren@nvidia.com>
lpc32xx_pwm_config() is supposed to set duty_ns and period_ns,
it should not change PWM_ENABLE bit.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Tested-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
According to the LPC32x0 User Manual [1]:
For both PWM1 and PWM2 Control Registers:
BIT 31:
This bit gates the PWM_CLK signal and enables the external output pin
to the PWM_PIN_STATE logical level.
0 = PWM disabled. (Default)
1 = PWM enabled
So in lpc32xx_pwm_enable(), we should set PWM_ENABLE bit.
In lpc32xx_pwm_disable(), we should just clear PWM_ENABLE bit rather than
write 0 to the register which will also clear PWMx_RELOADV and PWMx_DUTY bits.
[1] http://www.nxp.com/documents/user_manual/UM10326.pdf
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Tested-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
A few drivers already annotate this properly. Make the same change for
all other OF supporting drivers.
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Alexandre Pereira da Silva <aletes.xgr@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
PWM_ID_BASE() is not used after convert to PWM framework, remove it.
Also update driver_data field of struct platform_device_id accordingly.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Return proper error instead of 0 if twl6030_pwm_enable() fails.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
clk_enable/clk_disable maintain an enable_count, clk_prepare and clk_unprepare
also maintain a prepare_count. These APIs will do prepare/enable when the first
user calling these APIs, and do disable/unprepare when the corresponding counter
reach 0. Thus We don't need to maintain a clk_enabled counter here.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
We can test PWMF_ENABLED bit to know if pwm is enabled or not.
Thus remove enabled field from struct imx_chip.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Add missing .owner of struct pwm_ops. This prevents the module from being
removed from underneath its users.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Add missing .owner of struct pwm_ops. This prevents the module from being
removed from underneath its users.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Add missing .owner of struct pwm_ops. This prevents the module from being
removed from underneath its users.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Add missing .owner of struct pwm_ops. This prevents the module from being
removed from underneath its users.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Sachin Kamat