Document: devicetree: add OF documents for lantiq xway pinctrl

Signed-off-by: John Crispin <blogic@openwrt.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: linux-kernel@vger.kernel.org
This commit is contained in:
John Crispin 2012-07-20 19:01:00 +02:00
parent e316cb2b16
commit 5c56f76995
1 changed files with 97 additions and 0 deletions

View File

@ -0,0 +1,97 @@
Lantiq XWAY pinmux controller
Required properties:
- compatible: "lantiq,pinctrl-xway" or "lantiq,pinctrl-xr9"
- reg: Should contain the physical address and length of the gpio/pinmux
register range
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".
Lantiq's pin configuration nodes act as a container for an abitrary 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 group(s), and two pin configuration parameters:
pull-up and open-drain
The name of each subnode is not important as long as it is unique; all subnodes
should be enumerated and processed purely based on their content.
Each subnode only affects those parameters that are explicitly listed. In
other words, a subnode that lists a mux function but no pin configuration
parameters implies no information about any pin configuration parameters.
Similarly, a pin subnode that describes a pullup parameter implies no
information about e.g. the mux function.
We support 2 types of nodes.
Definition of mux function groups:
Required subnode-properties:
- lantiq,groups : An array of strings. Each string contains the name of a group.
Valid values for these names are listed below.
- lantiq,function: A string containing the name of the function to mux to the
group. Valid values for function names are listed below.
Valid values for group and function names:
mux groups:
exin0, exin1, exin2, jtag, ebu a23, ebu a24, ebu a25, ebu clk, ebu cs1,
ebu wait, nand ale, nand cs1, nand cle, spi, spi_cs1, spi_cs2, spi_cs3,
spi_cs4, spi_cs5, spi_cs6, asc0, asc0 cts rts, stp, nmi , gpt1, gpt2,
gpt3, clkout0, clkout1, clkout2, clkout3, gnt1, gnt2, gnt3, req1, req2,
req3
additional mux groups (XR9 only):
mdio, nand rdy, nand rd, exin3, exin4, gnt4, req4
functions:
spi, asc, cgu, jtag, exin, stp, gpt, nmi, pci, ebu, mdio
Definition of pin configurations:
Required subnode-properties:
- lantiq,pins : An array of strings. Each string contains the name of a pin.
Valid values for these names are listed below.
Optional subnode-properties:
- lantiq,pull: Integer, representing the pull-down/up to apply to the pin.
0: none, 1: down, 2: up.
- lantiq,open-drain: Boolean, enables open-drain on the defined pin.
Valid values for XWAY pin names:
Pinconf pins can be referenced via the names io0-io31.
Valid values for XR9 pin names:
Pinconf pins can be referenced via the names io0-io55.
Example:
gpio: pinmux@E100B10 {
compatible = "lantiq,pinctrl-xway";
pinctrl-names = "default";
pinctrl-0 = <&state_default>;
#gpio-cells = <2>;
gpio-controller;
reg = <0xE100B10 0xA0>;
state_default: pinmux {
stp {
lantiq,groups = "stp";
lantiq,function = "stp";
};
pci {
lantiq,groups = "gnt1";
lantiq,function = "pci";
};
conf_out {
lantiq,pins = "io4", "io5", "io6"; /* stp */
lantiq,open-drain;
lantiq,pull = <0>;
};
};
};