Add wifi.sta_ps_mode for ESP8266

mos.yml

@@ -85,6 +85,7 @@ conds:
       libs:
         - location: https://github.com/mongoose-os-libs/lwip
       config_schema:
+        - ["wifi.sta_ps_mode", "i", 0, {title: "WiFi sleep mode: 0 - none, 1 - light, 2 - modem"}]
         # min/max values are from enum RATE_11{B,G,N}_ID in the SDK, see user_interface.h for declarations.
         - ["wifi.tx_rate_limit_11b", "i", -1, {title: "TX rate limit for 11B mode, ((max << 8) | min)"}]
         - ["wifi.tx_rate_limit_11g", "i", -1, {title: "TX rate limit for 11G mode, ((max << 8) | min)"}]

src/esp8266/esp_wifi.c

@@ -130,15 +130,7 @@ static bool mgos_wifi_set_mode(uint8_t mode) {
   s_cur_mode = mode;
 
   if (mode == STATION_MODE) {
-    /*
-     * Turn off modem sleep.
-     * There is just no end to misery with it on.
-     * https://github.com/espressif/ESP8266_NONOS_SDK/issues/119 is particularly
-     * bad, but even without it there are regular disconnections reported by
-     * multiple people (and observed by us), sometimes with device never coming
-     * back (disconnect event getting lost).
-     */
-    wifi_set_sleep_type(NONE_SLEEP_T);
+    wifi_set_sleep_type(mgos_sys_config_get_wifi_sta_ps_mode());
   } else {
     /* When AP is active, modem sleep is not active anyway. */
   }