Yes, it is possible to control the SPI chip select (CS) pin with the Zephyr GPIO API. The Zephyr GPIO API provides a set of functions for configuring and controlling GPIO pins on a microcontroller.
To control the CS pin of an SPI device using the GPIO API, you would need to first configure a GPIO pin as an output pin using the gpio_pin_configure() function. Once the pin is configured, you can set its value to high or low using the gpio_pin_set() or gpio_pin_clear() functions, respectively.
Here's an example of how you could use the GPIO API to control the CS pin of an SPI device:
#include <zephyr.h>
#include <device.h>
#include <drivers/gpio.h>
// Define the CS pin
#define CS_PIN 10
// Configure the CS pin as an output
const struct device *gpio_dev;
gpio_pin_configure(gpio_dev, CS_PIN, GPIO_OUTPUT);
// Set the CS pin low to select the SPI device
gpio_pin_clear(gpio_dev, CS_PIN);
// Perform SPI transactions here...
// Set the CS pin high to deselect the SPI device
gpio_pin_set(gpio_dev, CS_PIN);
In this example, we first define the CS pin as CS_PIN, and then configure it as an output using the gpio_pin_configure() function. We then set the CS pin low using gpio_pin_clear() to select the SPI device and perform SPI transactions. Finally, we set the CS pin high using gpio_pin_set() to deselect the SPI device.
