I’m working in Zephyr to have a bit more control over the BLE, but I’m currently just trying to map a GPIO pin (12) to a device tree node defined in my overlay file that allocates gpios = <&gpio1 12 GPIO_ACTIVE_HIGH>; The problem is that pin 12 is already occupied by uart0_default. Therefore, I deleted the node and substituted a node in the overlay file (shown below).
> /delete-node/ &uart0_default;
> /delete-node/ &uart0_sleep;
> / {
> csn_pins {
> compatible = "spi-rhd";
> csn1: csn_1 {
> gpios = <&gpio1 12 GPIO_ACTIVE_LOW>;
> label = "csn manual gpio pin";
> };
> };
> };
I also have a corresponding yaml bindings folder in dts/bindings that defines the service:
description: |
test
compatible: "spi-rhd"
child-binding:
description: GPIO SPI CSN
properties:
gpios:
type: phandle-array
required: true
label:
type: string
description: |
Human readable string
Then I’m trying to just toggle the pin on a timer.
#include <zephyr/device.h>
#include <zephyr/devicetree.h>
#include <zephyr/drivers/gpio.h>
#include <zephyr/sys/printk.h>
#define CSN_NODE DT_NODELABEL(csn1)
static const struct gpio_dt_spec csn_spec = GPIO_DT_SPEC_GET(CSN_NODE, gpios);
int main(void) {
int ret;
ret = gpio_pin_configure_dt(&csn_spec, GPIO_OUTPUT_INIT_LOW);
while (1) {
gpio_pin_set_dt(&csn_spec, 0);
k_sleep(K_MSEC(1000));
gpio_pin_set_dt(&csn_spec, 1);
k_sleep(K_MSEC(1000));
}
}
So far, the code compiles and the new bindings are found and accepted, but I’m unable to see any change on the pin. Any pointers? I’m really confused why it is so hard to use an arbitrary pin on the board as a gpio.