Commit Graph

225 Commits

Author SHA1 Message Date
Bill Pemberton 77f37917a6 pwm: remove use of __devexit
CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:23:41 -08:00
Bill Pemberton 3e9fe83d27 pwm: remove use of __devinit
CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:23:41 -08:00
Bill Pemberton fd1091125a pwm: remove use of __devexit_p
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:23:41 -08:00
Peter Ujfalusi 6179a58ec7 pwm: Remove pwm-twl6030 driver
This driver only supported the Charging indicator LED.
New set of drivers going to provide support for both PWMs and LEDs for twl4030
and twl6030 series of PMICs.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:16:20 +01:00
Peter Ujfalusi aa7656471d pwm: New driver to support PWM driven LEDs on TWL4030/6030 series of PMICs
The driver supports the following LED outputs as generic PWM driver:
TWL4030 LEDA and LEDB (PWMA and PWMB)
TWL6030 Charging indicator LED (PWM LED)

On TWL6030 when the PWM requested LED is configured to be controlled by SW.
In this case the user can enable/disable and set the duty period freely.
When the PWM has been freed, the LED driver is put back to HW control.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:16:19 +01:00
Peter Ujfalusi 3744c26386 pwm: New driver to support PWMs on TWL4030/6030 series of PMICs
The driver supports the following PWM outputs:
TWL4030 PWM0 and PWM1
TWL6030 PWM1 and PWM2

On TWL4030 the PWM signals are muxed. Upon requesting the PWM the driver
will select the correct mux so the PWM can be used. When the PWM has been
freed the original configuration is going to be restored.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:16:19 +01:00
Philip, Avinash 98ccf49daf pwm: pwm-tiehrpwm: pinctrl support
Enable pinctrl for pwm-tiehrpwm if pinctrl driver available, else
bail out with warning message.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:16:18 +01:00
Philip, Avinash 53ad9e8d37 pwm: tiehrpwm: Add device-tree binding
This patch
1. Add support for device-tree binding for EHRWPM driver.
2. Set size of pwm-cells set to 3 to support PWM channel number, PWM
   period & polarity configuration from device tree.
3. Add enable/disable clock gating in PWM subsystem common config space.
4. When here set .owner member in platform_driver structure to
   THIS_MODULE.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:16:17 +01:00
Philip, Avinash d91861dafd pwm: pwm-tiehrpwm: Adding TBCLK gating support.
Some platforms (like AM33XX) requires clock gating from control module
explicitly for TBCLK. Enabling of this clock required for the
functioning of the time base sub module in EHRPWM module. Adding support
for handling by enabling the clock on PWM device enable & disable on PWM
device disable. Platforms don't have explicit TBCLK gating has to add
dummy TBCLK node.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:16:16 +01:00
Philip, Avinash 3db9b76d7b pwm: pwm-tiecap: pinctrl support
Enable pinctrl for pwm-tiecap if pinctrl driver available, else
bail out with warning message.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:16:16 +01:00
Philip, Avinash 333b08ee8c pwm: tiecap: Add device-tree binding
This patch
1. Add support for device-tree binding for ECAP APWM driver.
2. Set size of pwm-cells set to 3 to support PWM channel number, PWM
   period & polarity configuration from device tree.
3. Add enable/disable clock gating in PWM subsystem common config space.
4. When here set .owner member in platform_driver structure to
   THIS_MODULE.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:16:15 +01:00
Philip, Avinash af0ba001d2 pwm: Add TI PWM subsystem driver
In some platforms (like am33xx), PWM sub modules (ECAP, EHRPWM, EQEP)
are integrated to PWM subsystem. These PWM submodules has resources
shared and only one register bit-field is provided to control
module/clock enable/disable, makes it difficult to handle common
resources from independent PWMSS submodule drivers.

So the solution here implemented in this patch is, to create driver for
PWMSS and take the role of parent driver for PWM submodules. PWMSS
parent driver enumerates all the child nodes under PWMSS module. Also
symbol "pwmss_submodule_state_change" exported to enable clock gating
for individual PWMSS submodules, and submodule drivers has to enable
clock gating from their drivers.

As this is only supported during DT boot, the parent/child relationship
is created and populated in DT execution flow. The only required change
is inside DTS file, making EHRPWM & ECAP as a child to PWMSS node.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:14:41 +01:00
Philip, Avinash 83af24027b pwm: Device tree support for PWM polarity
Add support for encoding PWM properties in bit encoded form with
of_pwm_xlate_with_flags() function support. Platforms require platform
specific PWM properties has to populate in 3rd cell of the pwm-specifier
and PWM driver should also set .of_xlate support with this function.
Currently PWM property polarity encoded in bit position 0 of the third
cell in pwm-specifier.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-22 22:47:12 +01:00
Tony Prisk 422470a826 pwm: vt8500: Ensure PWM clock is enabled during pwm_config
This patch corrects a bug reported by Peter Vasil.

When all PWMs are disabled, PWM module may be disabled during
calls to pwm_config. This patch enables/disables the clock in
pwm_config to ensure the module is active before register read/
writes.

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Tested-by: Peter Vasil <petervasil@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-22 22:47:12 +01:00
Tony Prisk 2f9569f7ce pwm: vt8500: Fix build error
A missing '{' causes a build error in pwm-vt8500.c

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-22 22:47:11 +01:00
Axel Lin c937136099 pwm: spear: Staticize spear_pwm_config()
spear_pwm_config() is not referenced outside of this file, make it static.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-22 22:47:10 +01:00
Shiraz Hashim ce20364bf7 pwm: Add SPEAr PWM chip driver support
Add support for PWM chips present on SPEAr platforms. These PWM
chips support 4 channel output with programmable duty cycle and
frequency.

More details on these PWM chips can be obtained from relevant
chapter of reference manual, present at following[1] location.

1. http://www.st.com/internet/mcu/product/251211.jsp

Cc: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Vipin Kumar <vipin.kumar@st.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-22 22:47:03 +01:00
Tony Prisk 63e1ed2364 pwm: vt8500: Update vt8500 PWM driver support
This patch updates pwm-vt8500.c to support devicetree probing and
make use of the common clock subsystem.

A binding document describing the PWM controller found on
arch-vt8500 is also included.

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-01 16:23:19 +01:00
Linus Torvalds 2474542f64 pwm: Changes for v3.7-rc1
All legacy PWM providers have now been moved to the PWM subsystem. The
 plan for 3.8 is to adapt all board files to provide a lookup table for
 PWM devices in order to get rid of the global namespace. Subsequently,
 users of the legacy pwm_request() and pwm_free() functions can be
 migrated to the new pwm_get() and pwm_put() functions. Once this has
 been completed, the legacy API and the compatibility code in the core
 can be removed.
 
 In addition to the above, these changes also add support for configuring
 the polarity of a PWM signal (currently only supported on ECAP and
 EHRPWM) and include a much needed rework of the i.MX driver. Managed
 functions to obtain and release a PWM device (devm_pwm_get() and
 devm_pwm_put()) have been added and the pwm-backlight driver has been
 updated to use them. If the PWM subsystem hasn't been enabled, dummy
 functions are provided that allow the subsystem to safely compile out.
 
 Some common checks on input parameters have been moved to the core and
 removed from the drivers. Finally, a small fix corrects the description
 of the PWM specifier's second cell in the device tree representation.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.19 (GNU/Linux)
 
 iQIcBAABAgAGBQJQcV6pAAoJEN0jrNd/PrOh594P/3NHPjnTiyAZpUICX4mJeoMd
 1rX685HofCyX5jlHloS1pLRXYtIPZP97We5crNR/k/RujKcHAqAFzLtG2Jj93gxm
 nRUwLZ4xbrAgeaZeJV8YG1naWx9R1OjrK2sv+FyHRWsn9UZus2vDMV7tB0oNWo9k
 DMhtF1q7gQxx4nRu8z9FFybyItQinVREODNs+Gdv6AOJ36t+mOsGPL3LKZeFsIG3
 LdaB1p3t/07Job4KwGYYRjkOR7bIQ+ADnnO8Pkk0a9lxkMI8rA0uFbLwgyx7Hohh
 xZtm8R5il2IlHwqh52RzpShceWICxCZ3htuIXTRbVa1PSEsBzZ66W2CT7sy1jPm5
 lJlHgc7abaiwijtoG76I+Lgslv5UTViBuIYHSX4dH2kF3Jgm2SgTBNzZYePI5MMT
 BI3xc9WnwBpxgMybJsPHfU0Ff6O/9h9ab7q5lBOHkQJittahYxzWD+FgYlalcAa+
 I919iFREKNZytewLnXu+4TG0RfacQoj6D5G+SquOGmXyKYRhhJ1O6WodnRZHi/0n
 M6J0f6fLxpomI1RMn44VYP43OPJCDYxgXYoDLwCZQL9tSWYpdhXoDrjcIPO547w1
 ZS5HTXUE4DrxeYjoeqL555vtQIooM9CuH4JwKlz5zzea8NPC8eVtmNFTTWE6wKWX
 ZIOOLVvw/FI0/DSjBb8H
 =MQ5V
 -----END PGP SIGNATURE-----

Merge tag 'for-3.7-rc1' of git://gitorious.org/linux-pwm/linux-pwm

Pull pwm changes from Thierry Reding:
 "All legacy PWM providers have now been moved to the PWM subsystem.
  The plan for 3.8 is to adapt all board files to provide a lookup table
  for PWM devices in order to get rid of the global namespace.
  Subsequently, users of the legacy pwm_request() and pwm_free()
  functions can be migrated to the new pwm_get() and pwm_put()
  functions.  Once this has been completed, the legacy API and the
  compatibility code in the core can be removed.

  In addition to the above, these changes also add support for
  configuring the polarity of a PWM signal (currently only supported on
  ECAP and EHRPWM) and include a much needed rework of the i.MX driver.
  Managed functions to obtain and release a PWM device (devm_pwm_get()
  and devm_pwm_put()) have been added and the pwm-backlight driver has
  been updated to use them.  If the PWM subsystem hasn't been enabled,
  dummy functions are provided that allow the subsystem to safely
  compile out.

  Some common checks on input parameters have been moved to the core and
  removed from the drivers.  Finally, a small fix corrects the
  description of the PWM specifier's second cell in the device tree
  representation."

* tag 'for-3.7-rc1' of git://gitorious.org/linux-pwm/linux-pwm: (23 commits)
  pwm: dt: Fix description of second PWM cell
  pwm: Check for negative duty-cycle and period
  pwm: Add Ingenic JZ4740 support
  MIPS: JZ4740: Export timer API
  pwm: Move PUV3 PWM driver to PWM framework
  unicore32: pwm: Use managed resource allocations
  unicore32: pwm: Remove unnecessary indirection
  unicore32: pwm: Use module_platform_driver()
  unicore32: pwm: Properly remap memory-mapped registers
  pwm-backlight: Use devm_pwm_get() instead of pwm_get()
  pwm: Move AB8500 PWM driver to PWM framework
  pwm: Fix compilation error when CONFIG_PWM is not defined
  pwm: i.MX: fix clock lookup
  pwm: i.MX: use per clock unconditionally
  pwm: i.MX: add devicetree support
  pwm: i.MX: Use module_platform_driver
  pwm: i.MX: add functions to enable/disable pwm.
  pwm: i.MX: remove unnecessary if in pwm_[en|dis]able
  pwm: i.MX: factor out SoC specific functions
  pwm: pwm-tiehrpwm: Add support for configuring polarity of PWM
  ...
2012-10-10 20:15:24 +09:00
Thierry Reding c2d476a98f pwm: Check for negative duty-cycle and period
Make sure the duty-cycle and period passed in are not negative. This
should eventually be made implicit by making them unsigned. While at
it, the drivers' .config() implementations can have the equivalent
checks removed.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Axel Lin <axel.lin@gmail.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Cc: Jonghwan Choi <jhbird.choi@samsung.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: "Philip, Avinash" <avinashphilip@ti.com>
Cc: Vaibhav Bedia <vaibhav.bedia@ti.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
2012-10-05 20:56:43 +02:00
Thierry Reding f6b8a57000 pwm: Add Ingenic JZ4740 support
This commit moves the driver to drivers/pwm and converts it to the new
PWM framework.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Tested-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
2012-10-05 20:56:42 +02:00
Thierry Reding 79c11b6fa0 pwm: Move PUV3 PWM driver to PWM framework
This commit moves the driver to drivers/pwm and converts it to the new
PWM framework.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Tested-by: Qin Rui <qinrui@mprc.pku.edu.cn>
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
2012-10-05 20:56:41 +02:00
Linus Torvalds 578f1ef91a MFD bits for the 3.7 merge window.
As usual we have a few new drivers:
 
 - TI LP8788
 - TI OMAP USB TLL
 - Maxim MAX8907
 - SMSC ECE1099
 - Dialog Semiconductor DA9055
 - A simpler syscon driver that allow us to get rid of the anatop one.
 
 Drivers are also gradually getting Device Tree and IRQ domain support.
 
 The following drivers got DT support:
 - palmas, 88pm860x, tc3589x and twl4030-audio
 
 And those ones now use the IRQ domain APIs:
 - 88pm860x, tc3589x, db8500_prcmu
 
 Also some other interesting changes:
 - Intel's ICH LPC now supports Lynx Point
 - TI's twl4030-audio added a GPO child
 - tps6527 enabled its backlight subdevice
 - The twl6030 pwm driver moved to the new PWM subsystem
 
 And finally a bunch of cleanup and casual fixes for mc13xxx, 88pm860x, palmas,
 ab8500, wm8994, wm5110, max8907 and the tps65xxx family.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 
 iQIcBAABAgAGBQJQbVq4AAoJEIqAPN1PVmxKXOsP/ifwoqYkaGUsZ7M8b8iTTxlk
 a0/SBU1O+FDG7LbIsOyJ6VZCpipj8R4WyVqNdS2CSPVoSdT8KnakrxFY9FAtcmpA
 c6O7r+9dymcT7HeQ6mBQYYeEyXcZQkTXj9Y298zuRT88gccH5PQIOX8DTj6gKVxN
 xhuDuAWtizvwAJWfof/57p7JLilCF96Hq0UdeISD10UWJPxPmXFJTzzYw6GbPPOl
 zk1N6yig3VpK6sfK+QdqZykHFKj23RX57SmceHOISTpEr66ayuKIkJEqWm/IydMO
 XWDTT2IN80ca+1PnbrQOyiMtXg3EKrZN5WDEp2AcUiKP0fnAoZBTeuZUkqyLc3rJ
 W8LowQe6x5154CeLwcJc4+kmeGUhbj09GHKCsI7x/lQpMWgJCaGHGvLxAUE1uRZi
 4Bn9IUP7OqE465fNolLOd1fRxgzWJxe5rBYKQB7UcOrS0NThPhu0r0qV905zBrBO
 tyCZz+PexTiirpbv1K0dMTcpWeHVOmtYG5uJTmw9wTRv7jW7aUhkhkW5Q+E5BAdb
 9Rj5/vYertqI3VzRQ1w2z1SavzBO3OykTURWGDkwjfFWYbJtEdPYGGjRSFiphVYG
 8jvs5UzrDm2ICqkpkKzovVWi9lXyvNVVCgSwxHQeoPXfqb5dXLlbUZZBaCaQpRII
 XlItAJvIiUNIA8bXLoC8
 =n6lp
 -----END PGP SIGNATURE-----

Merge tag 'mfd-3.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6

Pull MFD changes from Samuel Ortiz:
 "MFD bits for the 3.7 merge window.

  As usual we have a few new drivers:

   - TI LP8788
   - TI OMAP USB TLL
   - Maxim MAX8907
   - SMSC ECE1099
   - Dialog Semiconductor DA9055
   - A simpler syscon driver that allow us to get rid of the anatop one.

  Drivers are also gradually getting Device Tree and IRQ domain support.

  The following drivers got DT support:
   - palmas, 88pm860x, tc3589x and twl4030-audio

  And those ones now use the IRQ domain APIs:
   - 88pm860x, tc3589x, db8500_prcmu

  Also some other interesting changes:
   - Intel's ICH LPC now supports Lynx Point
   - TI's twl4030-audio added a GPO child
   - tps6527 enabled its backlight subdevice
   - The twl6030 pwm driver moved to the new PWM subsystem

  And finally a bunch of cleanup and casual fixes for mc13xxx, 88pm860x,
  palmas, ab8500, wm8994, wm5110, max8907 and the tps65xxx family."

Fix up various annoying conflicts: the DT and IRQ domain support came in
twice and was already in 3.6. And then it was apparently rebased.

Guys, DON'T REBASE!

* tag 'mfd-3.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6: (89 commits)
  ARM: dts: Enable 88pm860x pmic
  mfd: 88pm860x: Move gpadc init into touch
  mfd: 88pm860x: Device tree support
  mfd: 88pm860x: Use irqdomain
  mfd: smsc: Add support for smsc gpio io/keypad driver
  backlight: tps65217_bl: Add missing platform_set_drvdata in tps65217_bl_probe
  mfd: DA9055 core driver
  mfd: tps65910: Add alarm interrupt of TPS65910 RTC to mfd device list
  mfd: wm5110: Add register patches for revision B
  mfd: wm5110: Disable control interface error report for WM5110 rev B
  mfd: max8907: Remove regulator-compatible from DT docs
  backlight: Add TPS65217 WLED driver
  mfd: Add backlight as subdevice to the tps65217
  mfd: Provide the PRCMU with its own IRQ domain
  mfd: Fix max8907 sparse warning
  mfd: Add lp8788 mfd driver
  mfd: dbx500: Provide a more accurate smp_twd clock
  mfd: rc5t583: Fix warning messages
  regulator: palmas: Add DT support
  mfd: palmas: Change regulator defns to better suite DT
  ...
2012-10-05 12:01:30 +09:00
Thierry Reding 6173f8f4ed pwm: Move AB8500 PWM driver to PWM framework
This commit moves the driver to drivers/pwm and converts it to the new
PWM framework.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arun Murthy <arun.murthy@stericsson.com>
2012-09-20 12:52:03 +02:00
Thierry Reding 48a364b758 pwm: Move TWL6030 PWM driver to PWM framework
This commit moves the driver to drivers/pwm and converts it to the new
PWM framework. In order for this to work properly, register the PWM as
child of the multi-function TWL6030 device.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2012-09-19 12:04:25 +02:00
Philipp Zabel 7b27c160c6 pwm: i.MX: fix clock lookup
The i.MX PWM core has two clocks: The ipg clock and the ipg highfreq
(peripheral) clock. The ipg clock has to be enabled for this hardware
to work. The actual PWM output can either be driven by the ipg clock
or the ipg highfreq. The ipg highfreq has the advantage that it runs
even when the SoC is in low power modes.
This patch requests both clocks and enables the ipg clock for accessing
registers and the peripheral clock to actually turn on the PWM.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-12 14:25:07 +02:00
Sascha Hauer 8d1c24bfd2 pwm: i.MX: use per clock unconditionally
The i.MX PWM module has two clocks: The ipg clock and the ipg highfreq
(peripheral) clock. The ipg clock has to be enabled for this hardware
to work. The actual PWM output can either be driven by the ipg clock
or the ipg highfreq. The ipg highfreq has the advantage that it runs
even when the SoC is in low power modes.
Use the always running clock also on i.MX25.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-12 14:25:06 +02:00
Philipp Zabel 479e2e301c pwm: i.MX: add devicetree support
At the same time remove platform based support. No user for
this driver has made it into mainline so far, so all we break
is out of tree stuff.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-12 14:25:06 +02:00
Sascha Hauer 208d038f47 pwm: i.MX: Use module_platform_driver
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-12 14:25:05 +02:00
Sascha Hauer 66ad6a613a pwm: i.MX: add functions to enable/disable pwm.
We used to enable/disable the PWM only by switching the
clock on or off. Instead, use the dedicated register bits.
These differ on different SoCs, so introduce a SoC specific
function for this.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-12 14:25:05 +02:00
Sascha Hauer 140827c148 pwm: i.MX: remove unnecessary if in pwm_[en|dis]able
The PWM core makes sure that pwm_enable/disable are called only
once. Still keep the enabled state since we will need it in
pwm_config.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-12 14:25:04 +02:00
Sascha Hauer 19e7333323 pwm: i.MX: factor out SoC specific functions
To cleanup the code and to make it easier to support different
SoCs.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-12 14:25:04 +02:00
Philip, Avinash daa5629b21 pwm: pwm-tiehrpwm: Add support for configuring polarity of PWM
EHRPWM hardware supports polarity configuration of PWM output. However
configuration of polarity done in hardware only in .enable() to ensure
PWM output present only after enabling PWM. This commit adds support for
polarity configuration for EHRPWM.
When being here, remove configuring of polarity during .config() and do
it explicitly from .set_polarity().

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-10 17:05:53 +02:00
Philip, Avinash 454870a44b pwm: pwm-tiecap: Add support for configuring polarity of PWM
ECAP APWM hardware supports polarity configuration of PWM output.
This commit adds support for polarity configuration of ECAP APWM.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-10 17:05:52 +02:00
Alexandre Courbot 6354316dbe pwm: add devm_pwm_get() and devm_pwm_put()
Add resource managed variants of pwm_get() and pwm_put() for
convenience. Code is largely inspired by the equivalent devm functions
of the regulator framework.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-10 17:05:45 +02:00
Philip, Avinash 0aa0869c3c pwm: Add support for configuring the PWM polarity
Some hardware supports inverting the polarity of the PWM signal. This
commit adds support to the PWM framework to allow users of the PWM API
to configure the polarity. Note that in order to reduce complexity,
changing the polarity of a PWM signal is only allowed while the PWM is
disabled.

A practical example where this can prove useful is to simulate inversion
of the duty cycle. While inversion of polarity and duty cycle are not
exactly the same, the differences for most use-cases are negligible.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-10 17:05:44 +02:00
Philip, Avinash 01b2d4536f pwm: pwm-tiehrpwm: Fix conflicting channel period setting
EHRPWM hardware supports 2 independent PWM channels. However the device
uses only one register to handle period setting for both channels. So
both channels should be configured for same period (in nsec).

Fix the same by returning error for conflicting period values.

However, allow
1. Configuration of period settings if not conflicting with other
channels
2. Re-configuring of period settings if no other channels being
configured

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-10 17:04:38 +02:00
Philip, Avinash c06fad9d28 pwm: pwm-tiecap: Disable APWM mode after configure
APWM mode is enabled while configuring PWM device. This was done to
handle shadow & immediate mode update of period and compare registers.
However, leaving it enabled after configuring will cause APWM output on
PWM pin even before enabling PWM device.
Fix the same by disabling APWM mode after configuring if PWM device is
not running.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-10 17:03:13 +02:00
Thierry Reding b817bf5c72 pwm: Improve Kconfig help text
The Kconfig help text should help the user understand what functionality
is provided by an option. This is especially true for new subsystems. An
improved help text is provided by this commit in the hopes of clarifying
the usefulness of the PWM framework.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Borislav Petkov <bp@alien8.de>
2012-08-20 11:58:43 +02:00
Sachin Kamat e50d3523ff pwm: core: Fix coding style issues
Fixes the following:
WARNING: line over 80 characters
ERROR: spaces required around that ':' (ctx:VxW)
WARNING: Prefer pr_warn(... to pr_warning(...

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-08-17 14:08:26 +02:00
Sachin Kamat eba7cbe5d8 pwm: vt8500: Fix coding style issue
Fixes the following:
WARNING: Prefer pr_warn(... to pr_warning(...
	pr_warning("Waiting for status bits 0x%x to clear timed out\n",

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-08-17 14:08:25 +02:00
Axel Lin 2ffdc9a648 pwm: Remove a redundant error message when devm_request_and_ioremap fails
The implementation in devm_request_and_ioremap() already shows error message,
so no need to show dev_err again if devm_request_and_ioremap() fails.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-08-17 14:08:25 +02:00
Jingoo Han ecefeb7921 pwm: samsung: add missing device pointer to struct pwm_chip
This patch adds missing device pointer to struct pwm_chip. If the
device pointer is NULL, pwmchip_add() will return error.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-08-17 14:08:24 +02:00
Sachin Kamat dfeb86ecde pwm: Add missing static storage class specifiers in core.c file
Fixes the following sparse warnings:
drivers/pwm/core.c:152:6: warning:
symbol 'of_pwmchip_add' was not declared. Should it be static?
drivers/pwm/core.c:165:6: warning:
symbol 'of_pwmchip_remove' was not declared. Should it be static?

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-08-17 14:08:24 +02:00
Philip, Avinash 19891b20e7 pwm: pwm-tiehrpwm: PWM driver support for EHRPWM
Enhanced high resolution PWM module (EHRPWM) hardware can be used to
generate PWM output over 2 channels. This commit adds PWM driver support
for EHRPWM device present on AM33XX SOC. Current implementation supports
simple PWM functionality.

Reviewed-by: Vaibhav Bedia <vaibhav.bedia@ti.com>
Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-26 07:45:20 +02:00
Philip, Avinash 8e0cb05b3b pwm: pwm-tiecap: PWM driver support for ECAP APWM
ECAP hardware on AM33XX SOC supports auxiliary PWM (APWM) feature. This
commit adds PWM driver support for ECAP hardware on AM33XX SOC.

In the ECAP hardware, each PWM pin can also be configured to be in
capture mode. Current implementation only supports PWM mode of
operation. Also, hardware supports sync between multiple PWM pins but
the driver supports simple independent PWM functionality.

Reviewed-by: Vaibhav Bedia <vaibhav.bedia@ti.com>
Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-26 07:44:52 +02:00
Thierry Reding d295b12976 pwm: fix used-uninitialized warning in pwm_get()
Some versions of GCC don't seem no notice that the initialization of the
index variable is tied to that of the chip variable and falsely report
it as potentially being used uninitialized. However, to save anybody
else from tripping over this, we now initialize the index variable
unconditionally.

Originally-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:24:17 +02:00
Alexandre Pereira da Silva 2132fa8d95 pwm: add lpc32xx PWM support
Add lpc32xx SOC PWM driver.

Signed-off-by: Alexandre Pereira da Silva <aletes.xgr@gmail.com>
Acked-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:24:05 +02:00
Sachin Kamat 2437b0d95c pwm: Use pr_* functions in pwm-samsung.c file
Replace printk with pr_* functions to avoid checkpatch warnings.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:24:03 +02:00
Axel Lin 6192fa8744 pwm: Convert pwm-samsung to use devm_* APIs
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:24:03 +02:00
Axel Lin 0c8f527d8c pwm: Convert pwm-tegra to use devm_clk_get()
Also return proper error in tegra_pwm_remove() if pwmchip_remove()
fails.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:24:02 +02:00
Axel Lin 457fd768ee pwm: pwm-mxs: Return proper error if pwmchip_remove() fails
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:24:01 +02:00
Axel Lin b50675dcc3 pwm: pwm-bfin: Return proper error if pwmchip_remove() fails
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:24:00 +02:00
Thierry Reding abeaf75527 pwm: pxa: Propagate pwmchip_remove() error
If the pwmchip_remove() call fails, propagate the error to the driver's
remove callback. This is required to prevent the module from being
unloaded if a PWM provided by the driver is still in use.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:23:59 +02:00
Axel Lin 45b301d2b1 pwm: Convert pwm-pxa to use devm_* APIs
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:23:59 +02:00
Axel Lin 261995dd30 pwm: Convert pwm-vt8500 to use devm_* APIs
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:23:58 +02:00
Axel Lin a9970e3bec pwm: Convert pwm-imx to use devm_* APIs
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:23:57 +02:00
Thierry Reding eac7a92fd0 pwm: Conflict with legacy PWM API
In order to avoid duplicate symbols with legacy PWM API implementations,
the new PWM framework needs to conflict with any of the existing legacy
implementations. This is done in two ways: for implementations provided
by drivers, a conflict is added to the driver to ensure it will have to
be ported to the PWM subsystem before it can coexist with other PWM
providers. For architecture-specific code, the conflict is added to the
PWM symbol to avoid confusion when a previously picked platform or
machine can no longer be selected because of the PWM subsystem being
included.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:23:56 +02:00
Shawn Guo 1112fe88d4 pwm: pwm-mxs: add pinctrl support
Call pinctrl subsystem to set up pwm pin.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:23:56 +02:00
Shawn Guo 22d260bd88 pwm: pwm-mxs: use devm_* managed functions
Use devm_* managed functions to have a clean fail-out.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:23:55 +02:00
Shawn Guo 01bf32e949 pwm: pwm-mxs: use global reset function stmp_reset_block
Use global reset function stmp_reset_block instead of mxs_reset_block
to remove <mach/common.h> inclusion.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:23:54 +02:00
Shawn Guo 071407eefd pwm: pwm-mxs: encode soc name in compatible string
Encode soc name in the compatible string to know the specific version
hardware block.  This is the general approach adopted for most bindings.
Change mxs-pwm binding to use the approach.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-23 13:23:53 +02:00
Shawn Guo 4dce82c1e8 pwm: add pwm-mxs support
Add generic PWM framework driver (DT only) for Freescale MXS.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-02 22:06:34 +02:00
Sascha Hauer a245ccebb4 ARM vt8500: Move vt8500 pwm driver to pwm framework
Move the driver to drivers/pwm/ and convert it to use the framework.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-02 22:06:33 +02:00
Sascha Hauer 215c29d3d0 ARM Samsung: Move s3c pwm driver to pwm framework
Move the driver to drivers/pwm/ and convert it to use the framework.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
[eric@eukrea.com: fix pwmchip_add return code test]
Signed-off-by: Eric Bénard <eric@eukrea.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-02 21:39:02 +02:00
Sascha Hauer 29693248ed ARM i.MX: Move i.MX pwm driver to pwm framework
Move the driver to drivers/pwm/ and convert it to use the framework.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
[eric@eukrea.com: set chip.dev to prevent probe failure]
[eric@eukrea.com: fix pwmchip_add return code test]
Signed-off-by: Eric Bénard <eric@eukrea.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-02 21:39:01 +02:00
Thierry Reding 17b2b4780f pwm: Move PXA PWM driver to PWM framework
This commit moves the PXA PWM driver to the drivers/pwm subdirectory and
converts it to use the new PWM framework.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-02 21:39:00 +02:00
Thierry Reding a4315e3c11 pwm: Move Blackfin PWM driver to PWM framework
This commit moves the Blackfin PWM driver to the drivers/pwm sub-
directory and converts it to register with the new PWM framework.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-02 21:38:59 +02:00
Thierry Reding 140fd977dc pwm: tegra: Add device tree support
Add auxdata to instantiate the PWFM controller from a device tree,
include the corresponding nodes in the dtsi files for Tegra 20 and
Tegra 30 and add binding documentation.

Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-02 21:38:59 +02:00
Thierry Reding 0134b932a0 pwm: Add NVIDIA Tegra SoC support
This commit adds a generic PWM framework driver for the PWFM controller
found on NVIDIA Tegra SoCs. The driver is based on code from the
Chromium kernel tree and was originally written by Gary King (NVIDIA)
and later modified by Simon Que (Chromium).

Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-02 21:38:57 +02:00
Thierry Reding 7299ab70e6 pwm: Add device tree support
This patch adds helpers to support device tree bindings for the generic
PWM API. Device tree binding documentation for PWM controllers is also
provided.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-06-15 12:56:57 +02:00
Thierry Reding 8138d2ddbc pwm: Add table-based lookup for static mappings
In order to get rid of the global namespace for PWM devices, this commit
provides an alternative method, similar to that of the regulator or
clock frameworks, for registering a static mapping for PWM devices. This
works by providing a table with a provider/consumer map in the board
setup code.

With the new pwm_get() and pwm_put() functions available, usage of
pwm_request() and pwm_free() becomes deprecated.

Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-06-15 12:56:53 +02:00
Thierry Reding 62099abf67 pwm: Add debugfs interface
This commit adds a debugfs interface that can be used to list the
current internal state of the PWM devices registered with the PWM
framework.

Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-06-15 12:56:53 +02:00
Thierry Reding f051c466cf pwm: Allow chips to support multiple PWMs
Many PWM controllers provide access to more than a single PWM output and
may even share some resource among them. Allowing a PWM chip to provide
multiple PWM devices enables better sharing of those resources. As a
side-effect this change allows easy integration with the device tree
where a given PWM can be looked up based on the PWM chip's phandle and a
corresponding index.

This commit modifies the PWM core to support multiple PWMs per struct
pwm_chip. It achieves this in a similar way to how gpiolib works, by
allowing PWM ranges to be requested dynamically (pwm_chip.base == -1) or
starting at a given offset (pwm_chip.base >= 0). A chip specifies how
many PWMs it controls using the npwm member. Each of the functions in
the pwm_ops structure gets an additional argument that specified the PWM
number (it can be converted to a per-chip index by subtracting the
chip's base).

The total maximum number of PWM devices is currently fixed to 1024 while
the data is actually stored in a radix tree, thus saving resources if
not all of them are used.

Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
[eric@eukrea.com: fix error handling in pwmchip_add]
Signed-off-by: Eric Bénard <eric@eukrea.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-06-15 12:56:52 +02:00
Sascha Hauer 0c2498f166 pwm: Add PWM framework support
This patch adds framework support for PWM (pulse width modulation) devices.

The is a barebone PWM API already in the kernel under include/linux/pwm.h,
but it does not allow for multiple drivers as each of them implements the
pwm_*() functions.

There are other PWM framework patches around from Bill Gatliff. Unlike
his framework this one does not change the existing API for PWMs so that
this framework can act as a drop in replacement for the existing API.

Why another framework?

Several people argue that there should not be another framework for PWMs
but they should be integrated into one of the existing frameworks like led
or hwmon. Unlike these frameworks the PWM framework is agnostic to the
purpose of the PWM. In fact, a PWM can drive a LED, but this makes the
LED framework a user of a PWM, like already done in leds-pwm.c. The gpio
framework also is not suitable for PWMs. Every gpio could be turned into
a PWM using timer based toggling, but on the other hand not every PWM hardware
device can be turned into a gpio due to the lack of hardware capabilities.

This patch does not try to improve the PWM API yet, this could be done in
subsequent patches.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Kurt Van Dijck <kurt.van.dijck@eia.be>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Matthias Kaehlcke <matthias@kaehlcke.net>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
[thierry.reding@avionic-design.de: fixup typos, kerneldoc comments]
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-06-15 12:56:50 +02:00