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: NVaibhav Bedia <vaibhav.bedia@ti.com>
Signed-off-by: NPhilip, Avinash <avinashphilip@ti.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

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: NVaibhav Bedia <vaibhav.bedia@ti.com>
Signed-off-by: NPhilip, Avinash <avinashphilip@ti.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

Add lpc32xx SOC PWM driver.
Signed-off-by: NAlexandre Pereira da Silva <aletes.xgr@gmail.com>
Acked-by: NRoland Stigge <stigge@antcom.de>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

Add generic PWM framework driver (DT only) for Freescale MXS.
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

Move the driver to drivers/pwm/ and convert it to use the framework.
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Cc: Alexey Charkov <alchark@gmail.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

Move the driver to drivers/pwm/ and convert it to use the framework.
Signed-off-by: NSascha 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: NEric Bénard <eric@eukrea.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

Move the driver to drivers/pwm/ and convert it to use the framework.
Signed-off-by: NSascha 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: NEric Bénard <eric@eukrea.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

This commit moves the PXA PWM driver to the drivers/pwm subdirectory and
converts it to use the new PWM framework.
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

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: NThierry Reding <thierry.reding@avionic-design.de>

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: NStephen Warren <swarren@wwwdotorg.org>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

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: NSascha Hauer <s.hauer@pengutronix.de>
Acked-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NMatthias Kaehlcke <matthias@kaehlcke.net>
Reviewed-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: NShawn Guo <shawn.guo@linaro.org>
[thierry.reding@avionic-design.de: fixup typos, kerneldoc comments]
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>