nordic: watchdog: Cannot be initialized - circular dependency #8976
Description
I was looking at adding watchdog support in my Zephyr application. I was following Zephyr watchdog test as the watchdog sample uses the deprecated API.
The initialization code is pretty simple:
static int app_watchdog_init(void) {
int err;
struct device *wdt = device_get_binding(CONFIG_WDT_0_NAME);
if (wdt == NULL) {
printk("Could not find watchdog device %s\n", CONFIG_WDT_0_NAME);
return -ENODEV;
}
watchdog_cfg.callback = NULL;
watchdog_cfg.flags = WDT_FLAG_RESET_SOC;
watchdog_cfg.window.max = 2000;
err = wdt_install_timeout(wdt, &watchdog_cfg);
if (err < 0) {
return err;
}
err = wdt_setup(wdt, 0);
if (err < 0) {
return err;
}
return 0;
}
The issue is using this code, I have the following assert in Nordic HAL Watchdog driver:
assertion "m_state == NRFX_DRV_STATE_INITIALIZED" failed: file "/tmp/zephyr/ext/hal/nordic/nrfx/drivers/src/nrfx_wdt.c", line 119, function: nrfx_wdt_channel_alloc
The assert occurs in wdt_install_timeout(). It expects the HAL function nrfx_wdt_init() being invoked before nrfx_wdt_channel_alloc().
If I call wdt_setup() before calling wdt_install_timeout() I have a different assert:
assertion "m_alloc_index != 0" failed: file "/tmp/zephyr/ext/hal/nordic/nrfx/drivers/src/nrfx_wdt.c", line 97, function: nrfx_wdt_enable
Again, it expects a watchdog channel to be allocated. But it is only done by wdt_install_timeout().
One possible fix would be to call nrfx_wdt_init() in wdt_install_timeout() as Zephyr Watchdog API seems to require wdt_install_timeout() to be called before wdt_setup().
And Nordic Watchdog driver only supports one channel: https://github.com/zephyrproject-rtos/zephyr/blob/master/drivers/watchdog/wdt_nrfx.c#L126. So wdt_install_timeout() should only be called once.
cc: @kl-cruz