src: Disable PM mode during wifi join.

Had a few reports that joining wifi can be very slow. Disabling power
management seems to fix the problem. The PM mode is cleared when a join
is started and restored when complete on success or failure.

Fixes #9

Author: peterharperuk

src/cyw43.h

@@ -103,6 +103,7 @@ typedef struct _cyw43_t {
     bool pend_disassoc;
     bool pend_rejoin;
     bool pend_rejoin_wpa;
+    bool pend_restore_pm;
 
     // AP settings
     uint32_t ap_auth;
@@ -126,6 +127,9 @@ typedef struct _cyw43_t {
 
     // mac from otp (or from cyw43_hal_generate_laa_mac if not set)
     uint8_t mac[6];
+
+    // Power management setting, restored after connect
+    uint32_t saved_pm;
 } cyw43_t;
 
 extern cyw43_t cyw43_state;

src/cyw43_ctrl.c

@@ -103,6 +103,7 @@ void cyw43_init(cyw43_t *self) {
     self->pend_disassoc = false;
     self->pend_rejoin = false;
     self->pend_rejoin_wpa = false;
+    self->pend_restore_pm = false;
     self->ap_channel = 3;
     self->ap_ssid_len = 0;
     self->ap_key_len = 0;
@@ -235,6 +236,14 @@ STATIC void cyw43_poll_func(void) {
         self->wifi_join_state = WIFI_JOIN_STATE_ACTIVE;
     }
 
+    if (self->pend_restore_pm) {
+        self->pend_restore_pm = false;
+        if (self->saved_pm) {
+            cyw43_wifi_pm(self, self->saved_pm);
+            self->saved_pm = 0;
+        }
+    }
+
     if (cyw43_sleep == 0) {
         cyw43_ll_bus_sleep(&self->cyw43_ll, true);
         #if !USE_SDIOIT && !CYW43_USE_SPI
@@ -409,6 +418,12 @@ void cyw43_cb_process_async_event(void *cb_data, const cyw43_async_event_t *ev)
         self->wifi_join_state = WIFI_JOIN_STATE_ACTIVE;
         cyw43_cb_tcpip_set_link_up(self, CYW43_ITF_STA);
     }
+
+    // Restore power management value after wifi join
+    if ((self->wifi_join_state & WIFI_JOIN_STATE_KIND_MASK) != 0 && self->saved_pm) {
+        self->pend_restore_pm = true;
+        cyw43_schedule_internal_poll_dispatch(cyw43_poll_func);
+    }
 }
 
 /*******************************************************************************/
@@ -611,6 +626,11 @@ int cyw43_wifi_join(cyw43_t *self, size_t ssid_len, const uint8_t *ssid, size_t
         return ret;
     }
 
+    // Disable power management while connecting
+    if (cyw43_wifi_get_pm(self, &self->saved_pm) == 0) {
+        cyw43_wifi_pm(self, self->saved_pm & ~0xf);
+    }
+
     ret = cyw43_ll_wifi_join(&self->cyw43_ll, ssid_len, ssid, key_len, key, auth_type, bssid, channel);
 
     if (ret == 0) {