Add binding doc for Tegra 194 pinctrl driver Signed-off-by: Krishna Yarlagadda <kyarlagadda@xxxxxxxxxx> --- Changes in V3: remove optional fields not supported by pins published here .../bindings/pinctrl/nvidia,tegra194-pinmux.txt | 107 +++++++++++++++++++++ 1 file changed, 107 insertions(+) create mode 100644 Documentation/devicetree/bindings/pinctrl/nvidia,tegra194-pinmux.txt diff --git a/Documentation/devicetree/bindings/pinctrl/nvidia,tegra194-pinmux.txt b/Documentation/devicetree/bindings/pinctrl/nvidia,tegra194-pinmux.txt new file mode 100644 index 0000000..8763f44 --- /dev/null +++ b/Documentation/devicetree/bindings/pinctrl/nvidia,tegra194-pinmux.txt @@ -0,0 +1,107 @@ +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>; + }; + }; + }; -- 2.7.4