diff options
Diffstat (limited to 'Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt | 41 |
1 files changed, 26 insertions, 15 deletions
diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt index aeb3c995cc0..1958ca9f9e5 100644 --- a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt @@ -127,21 +127,20 @@ 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 pin configuration node content == -Generic pinconfig parameters can be used by defining a separate node containing -the applicable parameters (and optional values), like: +Many data items that are represented in a pin configuration node are common +and generic. Pin control bindings should use the properties defined below +where they are applicable; not all of these properties are relevant or useful +for all hardware or binding structures. Each individual binding document +should state which of these generic properties, if any, are used, and the +structure of the DT nodes that contain these properties. -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: +Supported generic properties are: +pins - the list of pins that properties in the node + apply to +function - the mux function to select bias-disable - disable any pin bias bias-high-impedance - high impedance mode ("third-state", "floating") bias-bus-hold - latch weakly @@ -160,7 +159,21 @@ 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 -Arguments for parameters: +Some of the generic properties take arguments. For those that do, the +arguments are described below. + +- pins takes a list of pin names or IDs as a required argument. The specific + binding for the hardware defines: + - Whether the entries are integers or strings, and their meaning. + +- function takes a list of function names/IDs as a required argument. The + specific binding for the hardware defines: + - Whether the entries are integers or strings, and their meaning. + - Whether only a single entry is allowed (which is applied to all entries + in the pins property), or whether there may alternatively be one entry per + entry in the pins property, in which case the list lengths must match, and + for each list index i, the function at list index i is applied to the pin + at list index i. - bias-pull-up, -down and -pin-default take as optional argument on hardware supporting it the pull strength in Ohm. bias-disable will disable the pull. @@ -170,7 +183,5 @@ Arguments for parameters: - 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> |