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1c353aea2b
This commit adds basic support for PWM found on Allwinner A64. It can be used for pwm_backlight driver (e.g. for Pinebook) Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
52 lines
2 KiB
Text
52 lines
2 KiB
Text
config DM_PWM
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bool "Enable support for pulse-width modulation devices (PWM)"
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depends on DM
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help
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A pulse-width modulator emits a pulse of varying width and provides
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control over the duty cycle (high and low time) of the signal. This
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is often used to control a voltage level. The more time the PWM
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spends in the 'high' state, the higher the voltage. The PWM's
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frequency/period can be controlled along with the proportion of that
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time that the signal is high.
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config PWM_EXYNOS
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bool "Enable support for the Exynos PWM"
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depends on DM_PWM
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help
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This PWM is found on Samsung Exynos 5250 and other Samsung SoCs. It
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supports a programmable period and duty cycle. A 32-bit counter is
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used. It provides 5 channels which can be independently
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programmed. Channel 4 (the last) is normally used as a timer.
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config PWM_ROCKCHIP
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bool "Enable support for the Rockchip PWM"
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depends on DM_PWM
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help
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This PWM is found on RK3288 and other Rockchip SoCs. It supports a
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programmable period and duty cycle. A 32-bit counter is used.
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Various options provided in the hardware (such as capture mode and
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continuous/single-shot) are not supported by the driver.
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config PWM_SANDBOX
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bool "Enable support for the sandbox PWM"
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help
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This is a sandbox PWM used for testing. It provides 3 channels and
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records the settings passed into it, but otherwise does nothing
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useful. The PWM can be enabled but is not connected to any outputs
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so this is not very useful.
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config PWM_TEGRA
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bool "Enable support for the Tegra PWM"
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depends on DM_PWM
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help
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This PWM is found on Tegra 20 and other Nvidia SoCs. It supports
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four channels with a programmable period and duty cycle. Only a
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32KHz clock is supported by the driver but the duty cycle is
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configurable.
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config PWM_SUNXI
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bool "Enable support for the Allwinner Sunxi PWM"
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depends on DM_PWM
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help
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This PWM is found on H3, A64 and other Allwinner SoCs. It supports a
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programmable period and duty cycle. A 16-bit counter is used.
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