huawei: implement Huawei-specific CDMA signal quality checks

Many Huawei CDMA modems implement vendor commands for 1x and EVDO
signal quality, so use them since they are more accurate than the
generic signal checking.

(port of a similar patch for MM_06 by heiher <admin@heiher.info>)

plugins/huawei/mm-broadband-modem-huawei.c

@@ -42,6 +42,7 @@ static void iface_modem_3gpp_init (MMIfaceModem3gpp *iface);
 static void iface_modem_3gpp_ussd_init (MMIfaceModem3gppUssd *iface);
 static void iface_modem_cdma_init (MMIfaceModemCdma *iface);
 
+static MMIfaceModem *iface_modem_parent;
 static MMIfaceModem3gpp *iface_modem_3gpp_parent;
 static MMIfaceModemCdma *iface_modem_cdma_parent;
 
@@ -1216,7 +1217,6 @@ decode (MMIfaceModem3gppUssd *self,
 }
 
 /*****************************************************************************/
-/* Setup/Cleanup unsolicited events (CDMA interface) */
 
 static void
 huawei_1x_signal_changed (MMAtSerialPort *port,
@@ -1248,6 +1248,132 @@ huawei_evdo_signal_changed (MMAtSerialPort *port,
     mm_iface_modem_update_signal_quality (MM_IFACE_MODEM (self), (guint)quality);
 }
 
+/* Signal quality loading (Modem interface) */
+
+static guint
+modem_load_signal_quality_finish (MMIfaceModem *self,
+                                  GAsyncResult *res,
+                                  GError **error)
+{
+    if (g_simple_async_result_propagate_error (G_SIMPLE_ASYNC_RESULT (res), error))
+        return 0;
+
+    return GPOINTER_TO_UINT (g_simple_async_result_get_op_res_gpointer (
+                                 G_SIMPLE_ASYNC_RESULT (res)));
+}
+
+static void
+parent_load_signal_quality_ready (MMIfaceModem *self,
+                                  GAsyncResult *res,
+                                  GSimpleAsyncResult *simple)
+{
+    GError *error = NULL;
+    guint signal_quality;
+
+    signal_quality = iface_modem_parent->load_signal_quality_finish (self, res, &error);
+    if (error)
+        g_simple_async_result_take_error (simple, error);
+    else
+        g_simple_async_result_set_op_res_gpointer (simple,
+                                                   GUINT_TO_POINTER (signal_quality),
+                                                   NULL);
+    g_simple_async_result_complete (simple);
+    g_object_unref (simple);
+}
+
+static void
+signal_ready (MMBaseModem *self,
+              GAsyncResult *res,
+              GSimpleAsyncResult *simple)
+{
+    const gchar *response, *command;
+    gchar buf[5];
+    guint quality = 0, i = 0;
+
+    response = mm_base_modem_at_command_finish (self, res, NULL);
+    if (!response) {
+        /* Fallback to parent's method */
+        iface_modem_parent->load_signal_quality (
+            MM_IFACE_MODEM (self),
+            (GAsyncReadyCallback)parent_load_signal_quality_ready,
+            simple);
+        return;
+    }
+
+    command = g_object_get_data (G_OBJECT (simple), "command");
+    g_assert (command);
+    response = mm_strip_tag (response, command);
+    /* 'command' won't include the trailing ':' in the response, so strip that */
+    while ((*response == ':') || isspace (*response))
+        response++;
+
+    /* Sanitize response for mm_get_uint_from_str() which wants only digits */
+    memset (buf, 0, sizeof (buf));
+    while (i < (sizeof (buf) - 1) && isdigit (*response))
+        buf[i++] = *response++;
+
+    if (mm_get_uint_from_str (buf, &quality)) {
+        quality = CLAMP (quality, 0, 100);
+        g_simple_async_result_set_op_res_gpointer (simple,
+                                                   GUINT_TO_POINTER (quality),
+                                                   NULL);
+    } else {
+        g_simple_async_result_set_error (simple,
+                                         MM_CORE_ERROR,
+                                         MM_CORE_ERROR_FAILED,
+                                         "Couldn't parse %s response: '%s'",
+                                         command, response);
+    }
+
+    g_simple_async_result_complete (simple);
+    g_object_unref (simple);
+}
+
+static void
+modem_load_signal_quality (MMIfaceModem *self,
+                           GAsyncReadyCallback callback,
+                           gpointer user_data)
+{
+    GSimpleAsyncResult *result;
+    MMModemCdmaRegistrationState evdo_state = MM_MODEM_CDMA_REGISTRATION_STATE_UNKNOWN;
+    const char *command = "^CSQLVL";
+
+    mm_dbg ("loading signal quality...");
+    result = g_simple_async_result_new (G_OBJECT (self),
+                                        callback,
+                                        user_data,
+                                        modem_load_signal_quality);
+
+    /* 3GPP modems can just run parent's signal quality loading */
+    if (mm_iface_modem_is_3gpp (self)) {
+        iface_modem_parent->load_signal_quality (
+            self,
+            (GAsyncReadyCallback)parent_load_signal_quality_ready,
+            result);
+        return;
+    }
+
+    /* CDMA modems need custom signal quality loading */
+
+    g_object_get (G_OBJECT (self),
+                  MM_IFACE_MODEM_CDMA_EVDO_REGISTRATION_STATE, &evdo_state,
+                  NULL);
+    if (evdo_state > MM_MODEM_CDMA_REGISTRATION_STATE_UNKNOWN)
+        command = "^HDRCSQLVL";
+    g_object_set_data (G_OBJECT (result), "command", (gpointer) command);
+
+    mm_base_modem_at_command (
+        MM_BASE_MODEM (self),
+        command,
+        3,
+        FALSE,
+        (GAsyncReadyCallback)signal_ready,
+        result);
+}
+
+/*****************************************************************************/
+/* Setup/Cleanup unsolicited events (CDMA interface) */
+
 static void
 set_cdma_unsolicited_events_handlers (MMBroadbandModemHuawei *self,
                                       gboolean enable)
@@ -1732,6 +1858,8 @@ finalize (GObject *object)
 static void
 iface_modem_init (MMIfaceModem *iface)
 {
+    iface_modem_parent = g_type_interface_peek_parent (iface);
+
     iface->load_access_technologies = load_access_technologies;
     iface->load_access_technologies_finish = load_access_technologies_finish;
     iface->load_unlock_retries = load_unlock_retries;
@@ -1744,6 +1872,8 @@ iface_modem_init (MMIfaceModem *iface)
     iface->load_allowed_modes_finish = load_allowed_modes_finish;
     iface->set_allowed_modes = set_allowed_modes;
     iface->set_allowed_modes_finish = set_allowed_modes_finish;
+    iface->load_signal_quality = modem_load_signal_quality;
+    iface->load_signal_quality_finish = modem_load_signal_quality_finish;
 }
 
 static void