bindings/pinctrl/pinctrl-mcp23s08.txt

2 8-/16-bit I/O expander with serial interface (I2C/SPI)
5 - compatible : Should be
6     - "mcp,mcp23s08" (DEPRECATED) for  8 GPIO SPI version
7     - "mcp,mcp23s17" (DEPRECATED) for 16 GPIO SPI version
8     - "mcp,mcp23008" (DEPRECATED) for  8 GPIO I2C version or
9     - "mcp,mcp23017" (DEPRECATED) for 16 GPIO I2C version of the chip
11     - "microchip,mcp23s08" for  8 GPIO SPI version
12     - "microchip,mcp23s17" for 16 GPIO SPI version
13     - "microchip,mcp23s18" for 16 GPIO SPI version
14     - "microchip,mcp23008" for  8 GPIO I2C version or
15     - "microchip,mcp23017" for 16 GPIO I2C version of the chip
16     - "microchip,mcp23018" for 16 GPIO I2C version
19 - #gpio-cells : Should be two.
20   - first cell is the pin number
21   - second cell is used to specify flags as described in
22     'Documentation/devicetree/bindings/gpio/gpio.txt'. Allowed values defined by
23     'include/dt-bindings/gpio/gpio.h' (e.g. GPIO_ACTIVE_LOW).
24 - gpio-controller : Marks the device node as a GPIO controller.
25 - reg : For an address on its bus. I2C uses this a the I2C address of the chip.
26         SPI uses this to specify the chipselect line which the chip is
27         connected to. The driver and the SPI variant of the chip support
29         microchip,spi-present-mask below.
31 Required device specific properties (only for SPI chips):
32 - mcp,spi-present-mask (DEPRECATED)
33 - microchip,spi-present-mask : This is a present flag, that makes only sense for SPI
34         chips - as the name suggests. Multiple SPI chips can share the same
35         SPI chipselect. Set a bit in bit0-7 in this mask to 1 if there is a
36         chip connected with the corresponding spi address set. For example if
38         which is 0x08. mcp23s08 chip variant only supports bits 0-3. It is not
40         least one bit to 1 for SPI chips.
43 - spi-max-frequency = The maximum frequency this chip is able to handle
46 - #interrupt-cells : Should be two.
47   - first cell is the pin number
48   - second cell is used to specify flags.
49 - interrupt-controller: Marks the device node as a interrupt controller.
50 - drive-open-drain: Sets the ODR flag in the IOCON register. This configures
52 - reset-gpios: Corresponds to the active-low RESET# pin for the chip
55 - microchip,irq-mirror: Sets the mirror flag in the IOCON register. Devices
57         those that have 16 IOs) have two IO banks: IO 0-7 form bank 1 and
58         IO 8-15 are bank 2. These chips have two different interrupt outputs:
59         One for bank 1 and another for bank 2. If irq-mirror is set, both
64 - microchip,irq-active-high: Sets the INTPOL flag in the IOCON register. This
68 gpiom1: gpio@20 {
70         gpio-controller;
71         #gpio-cells = <2>;
74         interrupt-parent = <&gpio1>;
76         interrupt-controller;
77         #interrupt-cells=<2>;
78         microchip,irq-mirror;
81 Example SPI:
82 gpiom1: gpio@0 {
84         gpio-controller;
85         #gpio-cells = <2>;
86         microchip,spi-present-mask = <0x01>;
88         spi-max-frequency = <1000000>;
91 Pull-up configuration
94 If pins are used as output, they can also be configured with pull-ups. This is
97 Please refer file <devicetree/bindings/pinctrl/pinctrl-bindings.txt>
102 --------------------------
105 - pinctrl-names: A pinctrl state named per <pinctrl-bindings.txt>.
106 - pinctrl[0...n]: Properties to contain the phandle for pinctrl states per
107 		<pinctrl-bindings.txt>.
110 sub-node have following properties:
113 ------------------
114 - pins: List of pins. Valid values of pins properties are:
115 		      gpio0 ... gpio7 for the devices with 8 GPIO pins and
116 		      gpio0 ... gpio15 for the devices with 16 GPIO pins.
119 -------------------
121 <pinctrl-bindings.txt>. Absence of this property will leave the configuration
123 	bias-pull-up
125 Example with pinctrl to pull-up output pins:
126 gpio21: gpio@21 {
128 	gpio-controller;
129 	#gpio-cells = <0x2>;
131 	interrupt-parent = <&socgpio>;
133 	interrupt-names = "mcp23017@21 irq";
134 	interrupt-controller;
135 	#interrupt-cells = <0x2>;
136 	microchip,irq-mirror;
137 	pinctrl-names = "default";
138 	pinctrl-0 = <&i2cgpio0irq>, <&gpio21pullups>;
139 	reset-gpios = <&gpio6 15 GPIO_ACTIVE_LOW>;
146 		bias-pull-up;