On Thu, Jul 9, 2020 at 4:11 PM Rodolfo Giometti <giometti@xxxxxxxxxxxx> wrote:
> gpio_lines {
> compatible = "gpio-line";
>
> bypass0 {
> gpios = <&gpionb 10 GPIO_ACTIVE_HIGH>;
> mode = "out-low";
> };
>
> bypass1 {
> gpios = <&gpiosb 11 GPIO_ACTIVE_HIGH>;
> mode = "out-low";
> };
>
> key {
> gpios = <&gpionb 4 GPIO_ACTIVE_HIGH>;
> mode = "input";
> };
>
> motor {
> gpios = <&gpionb 8 GPIO_ACTIVE_HIGH>;
> mode = "out-high-open-drain";
> };
These mode = ... strings are really just a big confusion for me since
they reinvent several of the flags you can already give to the gpios,
see include/dt-bindings/gpio/gpio.h:
/* Bit 0 express polarity */
#define GPIO_ACTIVE_HIGH 0
#define GPIO_ACTIVE_LOW 1
/* Bit 1 express single-endedness */
#define GPIO_PUSH_PULL 0
#define GPIO_SINGLE_ENDED 2
/* Bit 2 express Open drain or open source */
#define GPIO_LINE_OPEN_SOURCE 0
#define GPIO_LINE_OPEN_DRAIN 4
/*
* Open Drain/Collector is the combination of single-ended open drain interface.
* Open Source/Emitter is the combination of single-ended open source interface.
*/
#define GPIO_OPEN_DRAIN (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_DRAIN)
#define GPIO_OPEN_SOURCE (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_SOURCE)
Yours,
Linus Walleij
