config DM_PWM bool "Enable support for pulse-width modulation devices (PWM)" depends on DM help A pulse-width modulator emits a pulse of varying width and provides control over the duty cycle (high and low time) of the signal. This is often used to control a voltage level. The more time the PWM spends in the 'high' state, the higher the voltage. The PWM's frequency/period can be controlled along with the proportion of that time that the signal is high. config PWM_ASPEED bool "Enable support for the Aspeed PWM" depends on DM_PWM help This PWM is found on Ast2600 SoCs. It supports a programmable period and duty cycle. It provides 16 channels which can be independently programmed. config PWM_AT91 bool "Enable support for PWM found on AT91 SoC's" depends on DM_PWM && ARCH_AT91 help Support for PWM hardware on AT91 based SoC. config PWM_CADENCE_TTC bool "Enable support for the Cadence TTC PWM" depends on DM_PWM && !CADENCE_TTC_TIMER help Cadence TTC can be configured as timer which is done via CONFIG_CADENCE_TTC_TIMER or as PWM. This is covering only PWM now. config PWM_CROS_EC bool "Enable support for the Chrome OS EC PWM" depends on DM_PWM help This PWM is found on several Chrome OS devices and controlled by the Chrome OS embedded controller. It may be used to control the screen brightness and/or the keyboard backlight depending on the device. config PWM_EXYNOS bool "Enable support for the Exynos PWM" depends on DM_PWM help This PWM is found on Samsung Exynos 5250 and other Samsung SoCs. It supports a programmable period and duty cycle. A 32-bit counter is used. It provides 5 channels which can be independently programmed. Channel 4 (the last) is normally used as a timer. config PWM_IMX bool "Enable support for i.MX27 and later PWM" help This PWM is found i.MX27 and later i.MX SoCs. config PWM_MESON bool "Enable support for Amlogic Meson SoCs PWM" depends on DM_PWM help This PWM is found on Amlogic Meson SoCs. It supports a programmable period and duty cycle for 2 independant channels. config PWM_MTK bool "Enable support for MediaTek PWM" depends on DM_PWM help This PWM is found on MT7622, MT7623, and MT7629. It supports a programmable period and duty cycle. config PWM_ROCKCHIP bool "Enable support for the Rockchip PWM" depends on DM_PWM help This PWM is found on RK3288 and other Rockchip SoCs. It supports a programmable period and duty cycle. A 32-bit counter is used. Various options provided in the hardware (such as capture mode and continuous/single-shot) are not supported by the driver. config PWM_SANDBOX bool "Enable support for the sandbox PWM" help This is a sandbox PWM used for testing. It provides 3 channels and records the settings passed into it, but otherwise does nothing useful. The PWM can be enabled but is not connected to any outputs so this is not very useful. config PWM_S5P bool "Enable non-DM support for S5P PWM" depends on (S5P || ARCH_NEXELL) default y config PWM_SIFIVE bool "Enable support for SiFive PWM" depends on DM_PWM help This PWM is found SiFive's FU540 and other SoCs. config PWM_TEGRA bool "Enable support for the Tegra PWM" depends on DM_PWM help This PWM is found on Tegra 20 and other Nvidia SoCs. It supports four channels with a programmable period and duty cycle. Only a 32KHz clock is supported by the driver but the duty cycle is configurable. config PWM_SUNXI bool "Enable support for the Allwinner Sunxi PWM" depends on DM_PWM help This PWM is found on H3, A64 and other Allwinner SoCs. It supports a programmable period and duty cycle. A 16-bit counter is used. config PWM_TI_EHRPWM bool "Enable support for EHRPWM PWM" depends on DM_PWM && ARCH_OMAP2PLUS default y help PWM driver support for the EHRPWM controller found on TI SOCs.