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: NThierry 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: NJingoo Han <jg1.han@samsung.com>

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

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

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: NAxel Lin <axel.lin@gmail.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

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>