1 /*
2 * Copyright (c) 2024 STMicroelectronics
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <zephyr/kernel.h>
8 #include <zephyr/device.h>
9 #include <zephyr/devicetree.h>
10 #include <zephyr/drivers/gpio.h>
11 #include <zephyr/sys/printk.h>
12 #include <stm32u5xx_ll_pwr.h>
13 #include <gpio/gpio_stm32.h>
14
15 #define SLEEP_TIME_MS 2000
16
17 static const struct gpio_dt_spec led =
18 GPIO_DT_SPEC_GET(DT_ALIAS(led0), gpios);
19
main(void)20 int main(void)
21 {
22 bool led_is_on = true;
23
24 /* Compute GPIO port to be passed to LL_PWR_EnableGPIOPullUp etc. */
25 const struct gpio_stm32_config *cfg = led.port->config;
26 uint32_t pwr_port = ((uint32_t)LL_PWR_GPIO_PORTA) + (cfg->port * 8);
27
28 __ASSERT_NO_MSG(gpio_is_ready_dt(&led));
29
30 printk("Device ready\n");
31 gpio_pin_configure_dt(&led, GPIO_OUTPUT_ACTIVE);
32
33 /* Enable the pull-up/pull-down feature globally.
34 * User can decide to not use this feature to further reduce power consumption
35 *
36 * This configuration is active only in STOP3 mode, so no need to disable it
37 * during wake up
38 */
39 LL_PWR_EnablePUPDConfig();
40
41 while (true) {
42 gpio_pin_set(led.port, led.pin, (int)led_is_on);
43 /* In STOP3, GPIOs are disabled. Only pull-up/pull-down can be enabled.
44 * So we enable pull-up/pull-down based on LED status
45 */
46 if (led_is_on) {
47 LL_PWR_DisableGPIOPullDown(pwr_port, (1 << led.pin));
48 LL_PWR_EnableGPIOPullUp(pwr_port, (1 << led.pin));
49 } else {
50 LL_PWR_DisableGPIOPullUp(pwr_port, (1 << led.pin));
51 LL_PWR_EnableGPIOPullDown(pwr_port, (1 << led.pin));
52 }
53
54 k_msleep(SLEEP_TIME_MS);
55 led_is_on = !led_is_on;
56 }
57 return 0;
58 }
59
