linux/Documentation/devicetree/bindings/pinctrl/nvidia,tegra194-pinmux.txt
Krishna Yarlagadda 2585a584f8 pinctrl: Add Tegra194 pinctrl DT bindings
Add binding doc for Tegra 194 pinctrl driver.

Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Tested-by: Vidya Sagar <vidyas@nvidia.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-06-01 19:20:08 +02:00

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NVIDIA Tegra194 pinmux controller
Required properties:
- compatible: "nvidia,tegra194-pinmux"
- reg: Should contain a list of base address and size pairs for:
- first entry: The APB_MISC_GP_*_PADCTRL registers (pad control)
- second entry: The PINMUX_AUX_* registers (pinmux)
Please refer to pinctrl-bindings.txt in this directory for details of the
common pinctrl bindings used by client devices, including the meaning of the
phrase "pin configuration node".
Tegra's pin configuration nodes act as a container for an arbitrary number of
subnodes. Each of these subnodes represents some desired configuration for a
pin, a group, or a list of pins or groups. This configuration can include the
mux function to select on those pin(s)/group(s), and various pin configuration
parameters, such as pull-up, tristate, drive strength, etc.
See the TRM to determine which properties and values apply to each pin/group.
Macro values for property values are defined in
include/dt-binding/pinctrl/pinctrl-tegra.h.
Required subnode-properties:
- nvidia,pins : An array of strings. Each string contains the name of a pin or
group. Valid values for these names are listed below.
Optional subnode-properties:
- nvidia,function: A string containing the name of the function to mux to the
pin or group.
- nvidia,pull: Integer, representing the pull-down/up to apply to the pin.
0: none, 1: down, 2: up.
- nvidia,tristate: Integer.
0: drive, 1: tristate.
- nvidia,enable-input: Integer. Enable the pin's input path.
enable :TEGRA_PIN_ENABLE and
disable or output only: TEGRA_PIN_DISABLE.
- nvidia,open-drain: Integer.
enable: TEGRA_PIN_ENABLE.
disable: TEGRA_PIN_DISABLE.
- nvidia,lock: Integer. Lock the pin configuration against further changes
until reset.
enable: TEGRA_PIN_ENABLE.
disable: TEGRA_PIN_DISABLE.
- nvidia,io-hv: Integer. Select high-voltage receivers.
normal: TEGRA_PIN_DISABLE
high: TEGRA_PIN_ENABLE
- nvidia,schmitt: Integer. Enables Schmitt Trigger on the input.
normal: TEGRA_PIN_DISABLE
high: TEGRA_PIN_ENABLE
- nvidia,drive-type: Integer. Valid range 0...3.
- nvidia,pull-down-strength: Integer. Controls drive strength. 0 is weakest.
The range of valid values depends on the pingroup. See "CAL_DRVDN" in the
Tegra TRM.
- nvidia,pull-up-strength: Integer. Controls drive strength. 0 is weakest.
The range of valid values depends on the pingroup. See "CAL_DRVUP" in the
Tegra TRM.
Valid values for pin and group names (nvidia,pin) are:
These correspond to Tegra PADCTL_* (pinmux) registers.
Mux groups:
These correspond to Tegra PADCTL_* (pinmux) registers. Any property
that exists in those registers may be set for the following pin names.
pex_l5_clkreq_n_pgg0, pex_l5_rst_n_pgg1
Drive groups:
These registers controls a single pin for which a mux group exists.
See the list above for the pin name to use when configuring the pinmux.
pex_l5_clkreq_n_pgg0, pex_l5_rst_n_pgg1
Valid values for nvidia,functions are:
pe5
Power Domain:
pex_l5_clkreq_n_pgg0 and pex_l5_rst_n_pgg1 are part of PCIE C5 power
partition. Client devices must enable this partition before accessing
these pins here.
Example:
tegra_pinctrl: pinmux: pinmux@2430000 {
compatible = "nvidia,tegra194-pinmux";
reg = <0x2430000 0x17000
0xc300000 0x4000>;
pinctrl-names = "pex_rst";
pinctrl-0 = <&pex_rst_c5_out_state>;
pex_rst_c5_out_state: pex_rst_c5_out {
pex_rst {
nvidia,pins = "pex_l5_rst_n_pgg1";
nvidia,schmitt = <TEGRA_PIN_DISABLE>;
nvidia,lpdr = <TEGRA_PIN_ENABLE>;
nvidia,enable-input = <TEGRA_PIN_DISABLE>;
nvidia,io-high-voltage = <TEGRA_PIN_ENABLE>;
nvidia,tristate = <TEGRA_PIN_DISABLE>;
nvidia,pull = <TEGRA_PIN_PULL_NONE>;
};
};
};