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Diffstat (limited to 'Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt index c95ea8278f87..b275be49a546 100644 --- a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt @@ -126,3 +126,55 @@ device; they may be grandchildren, for example. Whether this is legal, and whether there is any interaction between the child and intermediate parent nodes, is again defined entirely by the binding for the individual pin controller device. + +== Using generic pinconfig options == + +Generic pinconfig parameters can be used by defining a separate node containing +the applicable parameters (and optional values), like: + +pcfg_pull_up: pcfg_pull_up { + bias-pull-up; + drive-strength = <20>; +}; + +This node should then be referenced in the appropriate pinctrl node as a phandle +and parsed in the driver using the pinconf_generic_parse_dt_config function. + +Supported configuration parameters are: + +bias-disable - disable any pin bias +bias-high-impedance - high impedance mode ("third-state", "floating") +bias-bus-hold - latch weakly +bias-pull-up - pull up the pin +bias-pull-down - pull down the pin +bias-pull-pin-default - use pin-default pull state +drive-push-pull - drive actively high and low +drive-open-drain - drive with open drain +drive-open-source - drive with open source +drive-strength - sink or source at most X mA +input-enable - enable input on pin (no effect on output) +input-disable - disable input on pin (no effect on output) +input-schmitt-enable - enable schmitt-trigger mode +input-schmitt-disable - disable schmitt-trigger mode +input-debounce - debounce mode with debound time X +low-power-enable - enable low power mode +low-power-disable - disable low power mode +output-low - set the pin to output mode with low level +output-high - set the pin to output mode with high level +slew-rate - set the slew rate + +Arguments for parameters: + +- bias-pull-up, -down and -pin-default take as optional argument 0 to disable + the pull, on hardware supporting it the pull strength in Ohm. bias-disable + will also disable any active pull. + +- drive-strength takes as argument the target strength in mA. + +- input-debounce takes the debounce time in usec as argument + or 0 to disable debouncing + +All parameters not listed here, do not take an argument. + +More in-depth documentation on these parameters can be found in +<include/linux/pinctrl/pinconfig-generic.h> |