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linux/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.txt

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pwm: tegra: Add device tree support Add auxdata to instantiate the PWFM controller from a device tree, include the corresponding nodes in the dtsi files for Tegra 20 and Tegra 30 and add binding documentation. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2011-12-21 15:04:13 +08:00
Tegra SoC PWFM controller
Required properties:
dt-bindings: pwm: tegra: Add compatible string for Tegra186 Tegra186 has 8 different PWM controllers and each controller has only one output. Earlier SoC generations have 4 PWM outputs per controller. Add a device tree compatible string for Tegra186 to be able to differentiate between the two. Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-06-22 19:47:22 +08:00
- compatible: Must be:
- "nvidia,tegra20-pwm": for Tegra20
- "nvidia,tegra30-pwm", "nvidia,tegra20-pwm": for Tegra30
- "nvidia,tegra114-pwm", "nvidia,tegra20-pwm": for Tegra114
- "nvidia,tegra124-pwm", "nvidia,tegra20-pwm": for Tegra124
- "nvidia,tegra132-pwm", "nvidia,tegra20-pwm": for Tegra132
- "nvidia,tegra210-pwm", "nvidia,tegra20-pwm": for Tegra210
- "nvidia,tegra186-pwm": for Tegra186
pwm: tegra: Add device tree support Add auxdata to instantiate the PWFM controller from a device tree, include the corresponding nodes in the dtsi files for Tegra 20 and Tegra 30 and add binding documentation. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2011-12-21 15:04:13 +08:00
- reg: physical base address and length of the controller's registers
pwm: Update DT bindings to reference pwm.txt for cells documentation The PWM client cells format is documented in the generic pwm.txt documentation and duplicated in all PWM driver bindings. Remove duplicate information and reference pwm.txt instead. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Reviewed-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-07-18 06:54:23 +08:00
- #pwm-cells: should be 2. See pwm.txt in this directory for a description of
the cells format.
ARM: tegra: add missing clock documentation to DT bindings Many of the Tegra DT binding documents say nothing about the clocks or clock-names properties, yet those are present and required in DT files. This patch simply updates the documentation file to match the implicit definition of the binding, based on real-world DT content. All Tegra bindings that mention clocks are updated to have consistent wording and formatting of the clock-related properties. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-By: Terje Bergstrom <tbergstrom@nvidia.com>
2013-11-07 05:00:25 +08:00
- clocks: Must contain one entry, for the module clock.
See ../clocks/clock-bindings.txt for details.
ARM: tegra: document reset properties in DT bindings Update all the Tegra DT bindings to require resets/reset-names properties where the HW module has reset inputs. Remove any entries from clocks or clock-names that were only required to identify reset inputs, rather than referring to real clocks. This is a DT-ABI-incompatible change. It is the first of two changes required for me to consider the Tegra DT bindings as stable, the other being conversion to the common DMA DT bindings. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-By: Terje Bergstrom <tbergstrom@nvidia.com>
2013-11-08 01:11:27 +08:00
- resets: Must contain an entry for each entry in reset-names.
See ../reset/reset.txt for details.
- reset-names: Must include the following entries:
- pwm
pwm: tegra: Add device tree support Add auxdata to instantiate the PWFM controller from a device tree, include the corresponding nodes in the dtsi files for Tegra 20 and Tegra 30 and add binding documentation. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2011-12-21 15:04:13 +08:00
pwm: tegra: Add DT binding details to configure pin in suspends/resume In some of NVIDIA Tegra's platform, PWM controller is used to control the PWM controlled regulators. PWM signal is connected to the VID pin of the regulator where duty cycle of PWM signal decide the voltage level of the regulator output. When system enters suspend, some PWM client/slave regulator devices require the PWM output to be tristated. Add DT binding details to provide the pin configuration state from PWM and pinctrl DT node in suspend and active state of the system. Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> Acked-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2017-04-07 17:34:01 +08:00
Optional properties:
============================
In some of the interface like PWM based regulator device, it is required
to configure the pins differently in different states, especially in suspend
state of the system. The configuration of pin is provided via the pinctrl
DT node as detailed in the pinctrl DT binding document
Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
The PWM node will have following optional properties.
pinctrl-names: Pin state names. Must be "default" and "sleep".
pinctrl-0: phandle for the default/active state of pin configurations.
pinctrl-1: phandle for the sleep state of pin configurations.
pwm: tegra: Add device tree support Add auxdata to instantiate the PWFM controller from a device tree, include the corresponding nodes in the dtsi files for Tegra 20 and Tegra 30 and add binding documentation. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2011-12-21 15:04:13 +08:00
Example:
pwm: pwm@7000a000 {
compatible = "nvidia,tegra20-pwm";
reg = <0x7000a000 0x100>;
#pwm-cells = <2>;
ARM: tegra: add missing clock documentation to DT bindings Many of the Tegra DT binding documents say nothing about the clocks or clock-names properties, yet those are present and required in DT files. This patch simply updates the documentation file to match the implicit definition of the binding, based on real-world DT content. All Tegra bindings that mention clocks are updated to have consistent wording and formatting of the clock-related properties. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-By: Terje Bergstrom <tbergstrom@nvidia.com>
2013-11-07 05:00:25 +08:00
clocks = <&tegra_car 17>;
ARM: tegra: document reset properties in DT bindings Update all the Tegra DT bindings to require resets/reset-names properties where the HW module has reset inputs. Remove any entries from clocks or clock-names that were only required to identify reset inputs, rather than referring to real clocks. This is a DT-ABI-incompatible change. It is the first of two changes required for me to consider the Tegra DT bindings as stable, the other being conversion to the common DMA DT bindings. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-By: Terje Bergstrom <tbergstrom@nvidia.com>
2013-11-08 01:11:27 +08:00
resets = <&tegra_car 17>;
reset-names = "pwm";
pwm: tegra: Add device tree support Add auxdata to instantiate the PWFM controller from a device tree, include the corresponding nodes in the dtsi files for Tegra 20 and Tegra 30 and add binding documentation. Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2011-12-21 15:04:13 +08:00
};
pwm: tegra: Add DT binding details to configure pin in suspends/resume In some of NVIDIA Tegra's platform, PWM controller is used to control the PWM controlled regulators. PWM signal is connected to the VID pin of the regulator where duty cycle of PWM signal decide the voltage level of the regulator output. When system enters suspend, some PWM client/slave regulator devices require the PWM output to be tristated. Add DT binding details to provide the pin configuration state from PWM and pinctrl DT node in suspend and active state of the system. Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> Acked-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2017-04-07 17:34:01 +08:00
Example with the pin configuration for suspend and resume:
=========================================================
Suppose pin PE7 (On Tegra210) interfaced with the regulator device and
it requires PWM output to be tristated when system enters suspend.
Following will be DT binding to achieve this:
#include <dt-bindings/pinctrl/pinctrl-tegra.h>
pinmux@700008d4 {
pwm_active_state: pwm_active_state {
pe7 {
nvidia,pins = "pe7";
nvidia,tristate = <TEGRA_PIN_DISABLE>;
};
};
pwm_sleep_state: pwm_sleep_state {
pe7 {
nvidia,pins = "pe7";
nvidia,tristate = <TEGRA_PIN_ENABLE>;
};
};
};
pwm@7000a000 {
/* Mandatory PWM properties */
pinctrl-names = "default", "sleep";
pinctrl-0 = <&pwm_active_state>;
pinctrl-1 = <&pwm_sleep_state>;
};
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