unix: Update port to use the new event functions.

Necessary to get coverage of the new event functions.

Deletes the case that called usleep(delay) for mp_hal_delay_ms(), it seems
like this wouldn't have ever happened anyhow (MICROPY_EVENT_POOL_HOOK is
always defined for the unix port).

This work was funded through GitHub Sponsors.

Signed-off-by: Angus Gratton <angus@redyak.com.au>

ports/unix/coverage.c

@@ -578,9 +578,10 @@ STATIC mp_obj_t extra_coverage(void) {
         mp_sched_unlock();
         mp_printf(&mp_plat_print, "unlocked\n");
 
-        // drain pending callbacks
+        // drain pending callbacks, and test mp_event_wait_indefinite(), mp_event_wait_ms()
+        mp_event_wait_indefinite(); // the unix port only waits 500us in this call
         while (mp_sched_num_pending()) {
-            mp_handle_pending(true);
+            mp_event_wait_ms(1);
         }
 
         // setting the keyboard interrupt and raising it during mp_handle_pending

ports/unix/mpconfigport.h

@@ -222,14 +222,10 @@ static inline unsigned long mp_random_seed_init(void) {
 #endif
 
 // In lieu of a WFI(), slow down polling from being a tight loop.
-#ifndef MICROPY_EVENT_POLL_HOOK
-#define MICROPY_EVENT_POLL_HOOK \
-    do { \
-        extern void mp_handle_pending(bool); \
-        mp_handle_pending(true); \
-        usleep(500); /* equivalent to mp_hal_delay_us(500) */ \
-    } while (0);
-#endif
+//
+// Note that we don't delay for the full TIMEOUT_MS, as execution
+// can't be woken from the delay.
+#define MICROPY_INTERNAL_WFE(TIMEOUT_MS) mp_hal_delay_us(500)
 
 // Configure the implementation of machine.idle().
 #include <sched.h>

ports/unix/unix_mphal.c

@@ -237,17 +237,10 @@ uint64_t mp_hal_time_ns(void) {
 
 #ifndef mp_hal_delay_ms
 void mp_hal_delay_ms(mp_uint_t ms) {
-    #ifdef MICROPY_EVENT_POLL_HOOK
     mp_uint_t start = mp_hal_ticks_ms();
     while (mp_hal_ticks_ms() - start < ms) {
-        // MICROPY_EVENT_POLL_HOOK does usleep(500).
-        MICROPY_EVENT_POLL_HOOK
+        mp_event_wait_ms(1);
     }
-    #else
-    // TODO: POSIX et al. define usleep() as guaranteedly capable only of 1s sleep:
-    // "The useconds argument shall be less than one million."
-    usleep(ms * 1000);
-    #endif
 }
 #endif