Commit Graph

25 Commits

Author SHA1 Message Date
Laurent Pinchart 99b82abb0a pwm: Add Renesas TPU PWM driver
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>
2013-06-21 11:33:28 +02:00
H Hartley Sweeten 76abbdde2d pwm: Add sysfs interface
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>
2013-06-21 11:32:51 +02:00
Steffen Trumtrar 88b613e623 pwm: add pca9685 driver
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>
2013-06-12 13:13:18 +02:00
Boris BREZILLON 9421bade07 pwm: atmel: add Timer Counter Block PWM driver
This patch adds a PWM driver based on Atmel Timer Counter Block. The
Timer Counter Block is used in Waveform generator mode.

A Timer Counter Block provides up to 6 PWM devices grouped by 2:
* group 0 = PWM 0 and 1
* group 1 = PWM 2 and 3
* group 2 = PMW 4 and 5

PWM devices in a given group must be configured with the same period
value. If a PWM device in a group tries to change the period value and
the other device is already configured with a different value an error
will be returned.

This driver requires device tree support. The Timer Counter Block number
used to create a PWM chip is given by the tc-block field in an
"atmel,tcb-pwm" compatible node.

This patch was tested on kizbox board (at91sam9g20 SoC) with pwm-leds.

Signed-off-by: Boris BREZILLON <linux-arm@overkiz.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2013-01-08 16:52:10 +01:00
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 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
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
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.
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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 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
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
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
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
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 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
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