1 GPIO driver for Maxim MAX3191x industrial seri 1 GPIO driver for Maxim MAX3191x industrial serializer
2 2
3 Required properties: 3 Required properties:
4 - compatible: Must be one of: 4 - compatible: Must be one of:
5 "maxim,max31910" 5 "maxim,max31910"
6 "maxim,max31911" 6 "maxim,max31911"
7 "maxim,max31912" 7 "maxim,max31912"
8 "maxim,max31913" 8 "maxim,max31913"
9 "maxim,max31953" 9 "maxim,max31953"
10 "maxim,max31963" 10 "maxim,max31963"
11 - reg: Chip select number. 11 - reg: Chip select number.
12 - gpio-controller: Marks the device node 12 - gpio-controller: Marks the device node as a GPIO controller.
13 - #gpio-cells: Should be two. For con 13 - #gpio-cells: Should be two. For consumer use see gpio.txt.
14 14
15 Optional properties: 15 Optional properties:
16 - #daisy-chained-devices: 16 - #daisy-chained-devices:
17 Number of chips in the 17 Number of chips in the daisy-chain (default is 1).
18 - maxim,modesel-gpios: GPIO pins to configure 18 - maxim,modesel-gpios: GPIO pins to configure modesel of each chip.
19 The number of GPIOs mu 19 The number of GPIOs must equal "#daisy-chained-devices"
20 (if each chip is drive 20 (if each chip is driven by a separate pin) or 1
21 (if all chips are wire 21 (if all chips are wired to the same pin).
22 - maxim,fault-gpios: GPIO pins to read faul 22 - maxim,fault-gpios: GPIO pins to read fault of each chip.
23 The number of GPIOs mu 23 The number of GPIOs must equal "#daisy-chained-devices"
24 or 1. 24 or 1.
25 - maxim,db0-gpios: GPIO pins to configure 25 - maxim,db0-gpios: GPIO pins to configure debounce of each chip.
26 The number of GPIOs mu 26 The number of GPIOs must equal "#daisy-chained-devices"
27 or 1. 27 or 1.
28 - maxim,db1-gpios: GPIO pins to configure 28 - maxim,db1-gpios: GPIO pins to configure debounce of each chip.
29 The number of GPIOs mu 29 The number of GPIOs must equal "maxim,db0-gpios".
30 - maxim,modesel-8bit: Boolean whether the mo 30 - maxim,modesel-8bit: Boolean whether the modesel pin of the chips is
31 pulled high (8-bit mod 31 pulled high (8-bit mode). Use this if the modesel pin
32 is hardwired and conse 32 is hardwired and consequently "maxim,modesel-gpios"
33 cannot be specified. 33 cannot be specified. By default if neither this nor
34 "maxim,modesel-gpios" 34 "maxim,modesel-gpios" is given, the driver assumes
35 that modesel is pulled 35 that modesel is pulled low (16-bit mode).
36 - maxim,ignore-undervoltage: 36 - maxim,ignore-undervoltage:
37 Boolean whether to ign 37 Boolean whether to ignore undervoltage alarms signaled
38 by the "maxim,fault-gp 38 by the "maxim,fault-gpios" or by the status byte
39 (in 16-bit mode). Use 39 (in 16-bit mode). Use this if the chips are powered
40 through 5VOUT instead 40 through 5VOUT instead of VCC24V, in which case they
41 will constantly signal 41 will constantly signal undervoltage.
42 42
43 For other required and optional properties of 43 For other required and optional properties of SPI slave nodes please refer to
44 ../spi/spi-bus.txt. 44 ../spi/spi-bus.txt.
45 45
46 Example: 46 Example:
47 gpio@0 { 47 gpio@0 {
48 compatible = "maxim,max31913"; 48 compatible = "maxim,max31913";
49 reg = <0>; 49 reg = <0>;
50 gpio-controller; 50 gpio-controller;
51 #gpio-cells = <2>; 51 #gpio-cells = <2>;
52 52
53 maxim,modesel-gpios = <&gpio2 53 maxim,modesel-gpios = <&gpio2 23>;
54 maxim,fault-gpios = <&gpio2 54 maxim,fault-gpios = <&gpio2 24 GPIO_ACTIVE_LOW>;
55 maxim,db0-gpios = <&gpio2 55 maxim,db0-gpios = <&gpio2 25>;
56 maxim,db1-gpios = <&gpio2 56 maxim,db1-gpios = <&gpio2 26>;
57 57
58 spi-max-frequency = <25000000> 58 spi-max-frequency = <25000000>;
59 }; 59 };
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.