device-tree-bindings/pinctrl/pinctrl-bindings.txt

4 such as pull-up/down, tri-state, drive-strength etc are designated as pin
5 controllers. Each pin controller must be represented as a node in device tree,
13 set up certain specific pin configurations. Some client devices need a
15 need to reconfigure pins at run-time, for example to tri-state pins when the
25 For example, a pin controller may set up its own "active" state when the
31 they require certain specific named states for dynamic pin configuration.
47 pinctrl-0:	List of phandles, each pointing at a pin configuration
49 		nodes of the pin controller that they configure. Multiple
52 		from multiple nodes for a single pin controller, each
59 		used in an SoC either without a pin controller, or where the
60 		pin controller does not affect the HW module in question. If
65 pinctrl-1:	List of phandles, each pointing at a pin configuration
66 		node within a pin controller.
68 pinctrl-n:	List of phandles, each pointing at a pin configuration
69 		node within a pin controller.
70 pinctrl-names:	The list of names to assign states. List entry 0 defines the
78 		pinctrl-names = "active", "idle";
79 		pinctrl-0 = <&state_0_node_a>;
80 		pinctrl-1 = <&state_1_node_a &state_1_node_b>;
85 		pinctrl-0 = <&state_0_node_a>;
86 		pinctrl-1 = <&state_1_node_a &state_1_node_b>;
94 		pinctrl-names = "active", "idle";
95 		pinctrl-0 = <>;
96 		pinctrl-1 = <>;
99 == Pin controller devices ==
101 Pin controller devices should contain the pin configuration nodes that client
121 entirely by the binding for the individual pin controller device. There
124 The pin configuration nodes need not be direct children of the pin controller
128 controller device.
134 function		- the mux function to select
135 groups			- the list of groups to select with this function
137 pins			- the list of pins to select with this function (either
170 pins			- the list of pins that properties in the node
173 group			- the group to apply the properties to, if the driver
177 bias-disable		- disable any pin bias
178 bias-high-impedance	- high impedance mode ("third-state", "floating")
179 bias-bus-hold		- latch weakly
180 bias-pull-up		- pull up the pin
181 bias-pull-down		- pull down the pin
182 bias-pull-pin-default	- use pin-default pull state
183 drive-push-pull		- drive actively high and low
184 drive-open-drain	- drive with open drain
185 drive-open-source	- drive with open source
186 drive-strength		- sink or source at most X mA
187 input-enable		- enable input on pin (no effect on output)
188 input-disable		- disable input on pin (no effect on output)
189 input-schmitt-enable	- enable schmitt-trigger mode
190 input-schmitt-disable	- disable schmitt-trigger mode
191 input-debounce		- debounce mode with debound time X
192 power-source		- select between different power supplies
193 low-power-enable	- enable low power mode
194 low-power-disable	- disable low power mode
195 output-low		- set the pin to output mode with low level
196 output-high		- set the pin to output mode with high level
197 slew-rate		- set the slew rate
204 		bias-pull-up;
210 		output-high;
215 		group = "foo-group";
216 		bias-pull-up;
223 - pins takes a list of pin names or IDs as a required argument. The specific
225   - Whether the entries are integers or strings, and their meaning.
227 - bias-pull-up, -down and -pin-default take as optional argument on hardware
228   supporting it the pull strength in Ohm. bias-disable will disable the pull.
230 - drive-strength takes as argument the target strength in mA.
232 - input-debounce takes the debounce time in usec as argument
235 More in-depth documentation on these parameters can be found in
236 <include/linux/pinctrl/pinconf-generic.h>