mirror of
https://github.com/torvalds/linux.git
synced 2024-12-26 04:42:12 +00:00
31d610f196
Support gpio devicetree subnodes to allow a more detailed DT hardware description. Signed-off-by: Markus Pargmann <mpa@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
122 lines
3.1 KiB
Plaintext
122 lines
3.1 KiB
Plaintext
* Freescale IMX27 IOMUX Controller
|
|
|
|
Required properties:
|
|
- compatible: "fsl,imx27-iomuxc"
|
|
|
|
The iomuxc driver node should define subnodes containing of pinctrl configuration subnodes.
|
|
|
|
Required properties for pin configuration node:
|
|
- fsl,pins: three integers array, represents a group of pins mux and config
|
|
setting. The format is fsl,pins = <PIN MUX_ID CONFIG>.
|
|
|
|
PIN is an integer between 0 and 0xbf. imx27 has 6 ports with 32 configurable
|
|
configurable pins each. PIN is PORT * 32 + PORT_PIN, PORT_PIN is the pin
|
|
number on the specific port (between 0 and 31).
|
|
|
|
MUX_ID is
|
|
function + (direction << 2) + (gpio_oconf << 4) + (gpio_iconfa << 8) + (gpio_iconfb << 10)
|
|
|
|
function value is used to select the pin function.
|
|
Possible values:
|
|
0 - Primary function
|
|
1 - Alternate function
|
|
2 - GPIO
|
|
Registers: GIUS (GPIO In Use), GPR (General Purpose Register)
|
|
|
|
direction defines the data direction of the pin.
|
|
Possible values:
|
|
0 - Input
|
|
1 - Output
|
|
Register: DDIR
|
|
|
|
gpio_oconf configures the gpio submodule output signal. This does not
|
|
have any effect unless GPIO function is selected. A/B/C_IN are output
|
|
signals of function blocks A,B and C. Specific function blocks are
|
|
described in the reference manual.
|
|
Possible values:
|
|
0 - A_IN
|
|
1 - B_IN
|
|
2 - C_IN
|
|
3 - Data Register
|
|
Registers: OCR1, OCR2
|
|
|
|
gpio_iconfa/b configures the gpio submodule input to functionblocks A and
|
|
B. GPIO function should be selected if this is configured.
|
|
Possible values:
|
|
0 - GPIO_IN
|
|
1 - Interrupt Status Register
|
|
2 - Pulldown
|
|
3 - Pullup
|
|
Registers ICONFA1, ICONFA2, ICONFB1 and ICONFB2
|
|
|
|
CONFIG can be 0 or 1, meaning Pullup disable/enable.
|
|
|
|
|
|
The iomux controller has gpio child nodes which are embedded in the iomux
|
|
control registers. They have to be defined as child nodes of the iomux device
|
|
node. If gpio subnodes are defined "#address-cells", "#size-cells" and "ranges"
|
|
properties for the iomux device node are required.
|
|
|
|
Example:
|
|
|
|
iomuxc: iomuxc@10015000 {
|
|
compatible = "fsl,imx27-iomuxc";
|
|
reg = <0x10015000 0x600>;
|
|
#address-cells = <1>;
|
|
#size-cells = <1>;
|
|
ranges;
|
|
|
|
gpio1: gpio@10015000 {
|
|
...
|
|
};
|
|
|
|
...
|
|
|
|
uart {
|
|
pinctrl_uart1: uart-1 {
|
|
fsl,pins = <
|
|
0x8c 0x004 0x0 /* UART1_TXD__UART1_TXD */
|
|
0x8d 0x000 0x0 /* UART1_RXD__UART1_RXD */
|
|
0x8e 0x004 0x0 /* UART1_CTS__UART1_CTS */
|
|
0x8f 0x000 0x0 /* UART1_RTS__UART1_RTS */
|
|
>;
|
|
};
|
|
|
|
...
|
|
};
|
|
};
|
|
|
|
|
|
For convenience there are macros defined in imx27-pinfunc.h which provide PIN
|
|
and MUX_ID. They are structured as MX27_PAD_<Pad name>__<Signal name>. The names
|
|
are defined in the i.MX27 reference manual.
|
|
|
|
The above example using macros:
|
|
|
|
iomuxc: iomuxc@10015000 {
|
|
compatible = "fsl,imx27-iomuxc";
|
|
reg = <0x10015000 0x600>;
|
|
#address-cells = <1>;
|
|
#size-cells = <1>;
|
|
ranges;
|
|
|
|
gpio1: gpio@10015000 {
|
|
...
|
|
};
|
|
|
|
...
|
|
|
|
uart {
|
|
pinctrl_uart1: uart-1 {
|
|
fsl,pins = <
|
|
MX27_PAD_UART1_TXD__UART1_TXD 0x0
|
|
MX27_PAD_UART1_RXD__UART1_RXD 0x0
|
|
MX27_PAD_UART1_CTS__UART1_CTS 0x0
|
|
MX27_PAD_UART1_RTS__UART1_RTS 0x0
|
|
>;
|
|
};
|
|
|
|
...
|
|
};
|
|
};
|