linux/drivers/pwm/Kconfig

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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>
2011-01-28 08:40:40 +00:00
menuconfig PWM
bool "PWM Support"
help
This enables PWM support through the generic PWM framework.
You only need to enable this, if you also want to enable
one or more of the PWM drivers below.
If unsure, say N.
if PWM
config PWM_BFIN
tristate "Blackfin PWM support"
depends on BFIN_GPTIMERS
help
Generic PWM framework driver for Blackfin.
To compile this driver as a module, choose M here: the module
will be called pwm-bfin.
config PWM_IMX
tristate "i.MX pwm support"
depends on ARCH_MXC
help
Generic PWM framework driver for i.MX.
To compile this driver as a module, choose M here: the module
will be called pwm-imx.
config PWM_PXA
tristate "PXA PWM support"
depends on ARCH_PXA
help
Generic PWM framework driver for PXA.
To compile this driver as a module, choose M here: the module
will be called pwm-pxa.
config PWM_SAMSUNG
tristate "Samsung pwm support"
depends on PLAT_SAMSUNG
help
Generic PWM framework driver for Samsung.
To compile this driver as a module, choose M here: the module
will be called pwm-samsung.
config PWM_TEGRA
tristate "NVIDIA Tegra PWM support"
depends on ARCH_TEGRA
help
Generic PWM framework driver for the PWFM controller found on NVIDIA
Tegra SoCs.
To compile this driver as a module, choose M here: the module
will be called pwm-tegra.
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>
2011-01-28 08:40:40 +00:00
endif