serial: report port-not-open in queueing commands via callback

Reporting errors instead of just returning permits routines like
mm-generic-gsm.c:simple_get_status() to work again, as their callbacks
get the error they are expecting. To make this work, adapt get_csq_done()
to handle a NULL response when error is set, and make sure that multiple
errors don't step on each other in the mm_callback_info_chain() sequence
created by simple_get_status().

Change-Id: Ie3a72b1ce71b7f117e8b1f3da7a406c4d2da9e02

1 files changed, 9 insertions, 1 deletions

diff --git a/src/mm-serial-port.c b/src/mm-serial-port.c
index 29f99ef3..ab64dc80 100644
--- a/src/mm-serial-port.c
+++ b/src/mm-serial-port.c
@@ -1021,9 +1021,17 @@ internal_queue_command (MMSerialPort *self,
     MMQueueData *info;
 
     g_return_if_fail (MM_IS_SERIAL_PORT (self));
-    g_return_if_fail (priv->open_count > 0);
     g_return_if_fail (command != NULL);
 
+    if (priv->open_count == 0) {
+        GError *error = g_error_new_literal (MM_SERIAL_ERROR,
+                                             MM_SERIAL_ERROR_SEND_FAILED,
+                                             "Sending command failed: device is not enabled");
+        callback (self, NULL, error, user_data);
+        g_error_free (error);
+        return;
+    }
+
     info = g_slice_new0 (MMQueueData);
     if (take_command)
         info->command = command;