Pico W hangs connecting to WiFi in station mode #2186
Description
Pico W hangs calling cyw43_arch_wifi_connect_timeout_ms.
SDK Version: 2.1.0
Mode: pico_cyw43_arch_lwip_poll
Example: https://github.com/stfnmllr/pico-w-issue
In the example cyw43_arch_wifi_connect_timeout_ms is used to establish a connection and independently from success reboots the Pico W. Executing the program eventually stops progressing and hangs in cyw43_arch_wifi_connect_timeout_ms.
Changing the program not to reboot but calling cyw43_arch_wifi_connect_timeout_ms in a loop shows the same effect. I just used the watchdog in the example as this is closer to my real use case.
In case the Pico W is connected to a Serial Monitor (via USB), sending data is going to resume work and prints
[CYW43] do_ioctl(i, j, z): timeout
I couldn't reproduce the issue in pico_cyw43_arch_lwip_threadsafe_background mode on Pico W. I also couldn't reproduce the issue on Pico2 W whether in pico_cyw43_arch_lwip_poll nor in pico_cyw43_arch_lwip_threadsafe_background mode.
With Pico W the issue is reproducible using different Pico W and / or connecting it via USB to different USB ports and different machines.
As the warning is raised in cyw43_ll.c / cyw43_do_ioctl I did increase the timeout in
#define CYW43_DO_IOCTL_WAIT cyw43_await_background_or_timeout_us(1000);
from 1000 to 10000 us with no effect, but after adding a sleep (see below) the example program runs 'stable' on the Pico W continuously since several days.
diff --git a/src/cyw43_ll.c b/src/cyw43_ll.c
index 033eec2..9ce10ae 100644
--- a/src/cyw43_ll.c
+++ b/src/cyw43_ll.c
@@ -1186,6 +1186,7 @@ static int cyw43_do_ioctl(cyw43_int_t *self, uint32_t kind, uint32_t cmd, size_t
while (cyw43_hal_ticks_us() - start < CYW43_IOCTL_TIMEOUT_US) {
size_t res_len;
uint8_t *res_buf;
+ sleep_ms(10);
ret = cyw43_ll_sdpcm_poll_device(self, &res_len, &res_buf);
if (ret == CONTROL_HEADER) {
#if CYW43_USE_STATS