1fc760cb8SSimon Glassconfig DM_PWM 2fc760cb8SSimon Glass bool "Enable support for pulse-width modulation devices (PWM)" 3fc760cb8SSimon Glass depends on DM 4fc760cb8SSimon Glass help 5fc760cb8SSimon Glass A pulse-width modulator emits a pulse of varying width and provides 6fc760cb8SSimon Glass control over the duty cycle (high and low time) of the signal. This 7fc760cb8SSimon Glass is often used to control a voltage level. The more time the PWM 8fc760cb8SSimon Glass spends in the 'high' state, the higher the voltage. The PWM's 9fc760cb8SSimon Glass frequency/period can be controlled along with the proportion of that 10fc760cb8SSimon Glass time that the signal is high. 110e23fd81SSimon Glass 125c2dd4cdSSimon Glassconfig PWM_EXYNOS 135c2dd4cdSSimon Glass bool "Enable support for the Exynos PWM" 145c2dd4cdSSimon Glass depends on DM_PWM 155c2dd4cdSSimon Glass help 165c2dd4cdSSimon Glass This PWM is found on Samsung Exynos 5250 and other Samsung SoCs. It 175c2dd4cdSSimon Glass supports a programmable period and duty cycle. A 32-bit counter is 185c2dd4cdSSimon Glass used. It provides 5 channels which can be independently 195c2dd4cdSSimon Glass programmed. Channel 4 (the last) is normally used as a timer. 205c2dd4cdSSimon Glass 210e23fd81SSimon Glassconfig PWM_ROCKCHIP 220e23fd81SSimon Glass bool "Enable support for the Rockchip PWM" 230e23fd81SSimon Glass depends on DM_PWM 240e23fd81SSimon Glass help 250e23fd81SSimon Glass This PWM is found on RK3288 and other Rockchip SoCs. It supports a 260e23fd81SSimon Glass programmable period and duty cycle. A 32-bit counter is used. 270e23fd81SSimon Glass Various options provided in the hardware (such as capture mode and 280e23fd81SSimon Glass continuous/single-shot) are not supported by the driver. 2941fa035cSSimon Glass 30*43b41566SSimon Glassconfig PWM_SANDBOX 31*43b41566SSimon Glass bool "Enable support for the sandbox PWM" 32*43b41566SSimon Glass help 33*43b41566SSimon Glass This is a sandbox PWM used for testing. It provides 3 channels and 34*43b41566SSimon Glass records the settings passed into it, but otherwise does nothing 35*43b41566SSimon Glass useful. The PWM can be enabled but is not connected to any outputs 36*43b41566SSimon Glass so this is not very useful. 37*43b41566SSimon Glass 3841fa035cSSimon Glassconfig PWM_TEGRA 3941fa035cSSimon Glass bool "Enable support for the Tegra PWM" 4091c08afeSSimon Glass depends on DM_PWM 4141fa035cSSimon Glass help 4241fa035cSSimon Glass This PWM is found on Tegra 20 and other Nvidia SoCs. It supports 4341fa035cSSimon Glass four channels with a programmable period and duty cycle. Only a 4441fa035cSSimon Glass 32KHz clock is supported by the driver but the duty cycle is 4541fa035cSSimon Glass configurable. 46