[PATCH] update signal quality correctly when out of coverage

[Prathmesh Prabhu]

When querying signal quality using AT+CSQ, a response of '+CSQ:99,99' indicates no
network. This should lead to the signal quality being set to 0. Before this
patch, the last most recent signal quality would be left untouched.
---
 src/mm-iface-modem.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/mm-iface-modem.c b/src/mm-iface-modem.c
index 433dbac..ea433ed 100644
--- a/src/mm-iface-modem.c
+++ b/src/mm-iface-modem.c
@@ -1169,7 +1169,16 @@ signal_quality_check_ready (MMIfaceModem *self,
                                                                                       res,
                                                                                       &error);
     if (error) {
-        mm_dbg ("Couldn't refresh signal quality: '%s'", error->message);
+        /* If we failed to update signal quality because there was no network,
+         * we should set the signal quality to zero to reflect no network
+         * coverage.
+         */
+        if (error->code == MM_MOBILE_EQUIPMENT_ERROR_NO_NETWORK) {
+            mm_dbg ("Out of coverage area. Setting signal quality to '0'");
+            update_signal_quality (self, 0, TRUE);
+        } else {
+            mm_dbg ("Couldn't refresh signal quality: '%s'", error->message);
+        }
         g_error_free (error);
     } else
         update_signal_quality (self, signal_quality, TRUE);
-- 
1.8.4