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Tegra194 has multiple PWM controllers with each having only one output. Also the maxmimum frequency is higher than earlier SoCs. Add support for Tegra194 and specify the number of PWM outputs and maximum supported frequency using device tree match data. Signed-off-by: Sandipan Patra <spatra@nvidia.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Laxman Dewangan <ldewangan@nvidia.com> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
78 lines
2.7 KiB
Plaintext
78 lines
2.7 KiB
Plaintext
Tegra SoC PWFM controller
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Required properties:
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- compatible: Must be:
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- "nvidia,tegra20-pwm": for Tegra20
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- "nvidia,tegra30-pwm", "nvidia,tegra20-pwm": for Tegra30
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- "nvidia,tegra114-pwm", "nvidia,tegra20-pwm": for Tegra114
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- "nvidia,tegra124-pwm", "nvidia,tegra20-pwm": for Tegra124
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- "nvidia,tegra132-pwm", "nvidia,tegra20-pwm": for Tegra132
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- "nvidia,tegra210-pwm", "nvidia,tegra20-pwm": for Tegra210
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- "nvidia,tegra186-pwm": for Tegra186
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- "nvidia,tegra194-pwm": for Tegra194
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- reg: physical base address and length of the controller's registers
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- #pwm-cells: should be 2. See pwm.yaml in this directory for a description of
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the cells format.
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- clocks: Must contain one entry, for the module clock.
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See ../clocks/clock-bindings.txt for details.
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- resets: Must contain an entry for each entry in reset-names.
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See ../reset/reset.txt for details.
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- reset-names: Must include the following entries:
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- pwm
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Optional properties:
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============================
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In some of the interface like PWM based regulator device, it is required
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to configure the pins differently in different states, especially in suspend
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state of the system. The configuration of pin is provided via the pinctrl
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DT node as detailed in the pinctrl DT binding document
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Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
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The PWM node will have following optional properties.
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pinctrl-names: Pin state names. Must be "default" and "sleep".
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pinctrl-0: phandle for the default/active state of pin configurations.
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pinctrl-1: phandle for the sleep state of pin configurations.
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Example:
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pwm: pwm@7000a000 {
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compatible = "nvidia,tegra20-pwm";
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reg = <0x7000a000 0x100>;
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#pwm-cells = <2>;
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clocks = <&tegra_car 17>;
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resets = <&tegra_car 17>;
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reset-names = "pwm";
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};
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Example with the pin configuration for suspend and resume:
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=========================================================
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Suppose pin PE7 (On Tegra210) interfaced with the regulator device and
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it requires PWM output to be tristated when system enters suspend.
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Following will be DT binding to achieve this:
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#include <dt-bindings/pinctrl/pinctrl-tegra.h>
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pinmux@700008d4 {
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pwm_active_state: pwm_active_state {
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pe7 {
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nvidia,pins = "pe7";
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nvidia,tristate = <TEGRA_PIN_DISABLE>;
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};
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};
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pwm_sleep_state: pwm_sleep_state {
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pe7 {
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nvidia,pins = "pe7";
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nvidia,tristate = <TEGRA_PIN_ENABLE>;
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};
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};
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};
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pwm@7000a000 {
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/* Mandatory PWM properties */
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pinctrl-names = "default", "sleep";
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pinctrl-0 = <&pwm_active_state>;
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pinctrl-1 = <&pwm_sleep_state>;
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};
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