option/hso: check generic access tech first, then specific tech

During the explicit access technology check, the plugin would request
specific 2G (OCTI) and 3G (OWCTI) technologies explicitly.  Some devices
(like Nozomi) don't support the AT_OWCTI command, which leaves us with
only AT_OSSYS for determining whether the device is registered with
the 3G network or the 2G network.  So like the unsolicited mode change
handling code, when requesting access technology explicitly, ask for
generic 2G/3G tech first, and then get the specific tech.  If the
device doesn't support explicit 3G tech then at least we have the
generic 3G tech from OSSYS to use.

1 files changed, 107 insertions, 23 deletions

diff --git a/plugins/mm-modem-option-utils.c b/plugins/mm-modem-option-utils.c
index 61ca5d15..2316ee41 100644
--- a/plugins/mm-modem-option-utils.c
+++ b/plugins/mm-modem-option-utils.c
@@ -190,6 +190,22 @@ owcti_to_mm (char owcti, MMModemGsmAccessTech *out_act)
 }
 
 static gboolean
+ossys_to_mm (char ossys, MMModemGsmAccessTech *out_act)
+{
+    if (ossys == '0') {
+        *out_act = MM_MODEM_GSM_ACCESS_TECH_GPRS;
+        return TRUE;
+    } else if (ossys == '2') {
+        *out_act = MM_MODEM_GSM_ACCESS_TECH_UMTS;
+        return TRUE;
+    } else if (ossys == '3') {
+        *out_act = MM_MODEM_GSM_ACCESS_TECH_UNKNOWN;
+        return TRUE;
+    }
+    return FALSE;
+}
+
+static gboolean
 parse_octi_response (GString *response, MMModemGsmAccessTech *act)
 {
     MMModemGsmAccessTech cur_act = MM_MODEM_GSM_ACCESS_TECH_UNKNOWN;
@@ -222,6 +238,39 @@ parse_octi_response (GString *response, MMModemGsmAccessTech *act)
     return success;
 }
 
+static gboolean
+parse_ossys_response (GString *response, MMModemGsmAccessTech *act)
+{
+    MMModemGsmAccessTech cur_act = MM_MODEM_GSM_ACCESS_TECH_UNKNOWN;
+    const char *p;
+    GRegex *r;
+    GMatchInfo *match_info;
+    char *str;
+    gboolean success = FALSE;
+
+    g_return_val_if_fail (act != NULL, FALSE);
+    g_return_val_if_fail (response != NULL, FALSE);
+
+    p = mm_strip_tag (response->str, "_OSSYS:");
+
+    r = g_regex_new ("(\\d),(\\d)", G_REGEX_UNGREEDY, 0, NULL);
+    g_return_val_if_fail (r != NULL, FALSE);
+
+    g_regex_match (r, p, 0, &match_info);
+    if (g_match_info_matches (match_info)) {
+        str = g_match_info_fetch (match_info, 2);
+        if (str && ossys_to_mm (str[0], &cur_act)) {
+            *act = cur_act;
+            success = TRUE;
+        }
+        g_free (str);
+    }
+    g_match_info_free (match_info);
+    g_regex_unref (r);
+
+    return success;
+}
+
 static void
 ossys_octi_request_done (MMAtSerialPort *port,
                          GString *response,
@@ -261,18 +310,8 @@ option_ossys_tech_changed (MMAtSerialPort *port,
     char *str;
 
     str = g_match_info_fetch (info, 1);
-    if (str) {
-        switch (atoi (str)) {
-        case 0:
-            act = MM_MODEM_GSM_ACCESS_TECH_GPRS;
-            break;
-        case 2:
-            act = MM_MODEM_GSM_ACCESS_TECH_UMTS;
-            break;
-        default:
-            break;
-        }
-    }
+    if (str)
+        ossys_to_mm (str[0], &act);
     g_free (str);
 
     mm_generic_gsm_update_access_technology (MM_GENERIC_GSM (user_data), act);
@@ -408,7 +447,7 @@ get_act_octi_request_done (MMAtSerialPort *port,
 {
     MMCallbackInfo *info = user_data;
     MMModemGsmAccessTech octi = MM_MODEM_GSM_ACCESS_TECH_UNKNOWN;
-    MMModemGsmAccessTech owcti;
+    MMModemGsmAccessTech act;
 
     /* If the modem has already been removed, return without
      * scheduling callback */
@@ -417,9 +456,11 @@ get_act_octi_request_done (MMAtSerialPort *port,
 
     if (!error) {
         if (parse_octi_response (response, &octi)) {
-            /* If no 3G tech yet or current tech isn't 3G, then 2G tech is the best */
-            owcti = GPOINTER_TO_UINT (mm_callback_info_get_data (info, "owcti"));
-            if (octi && !owcti)
+            /* If current tech is 2G or unknown then use the more specific
+             * OCTI response.
+             */
+            act = GPOINTER_TO_UINT (mm_callback_info_get_result (info));
+            if (act < MM_MODEM_GSM_ACCESS_TECH_UMTS)
                 mm_callback_info_set_result (info, GUINT_TO_POINTER (octi), NULL);
         }
     }
@@ -444,13 +485,57 @@ get_act_owcti_request_done (MMAtSerialPort *port,
 
     if (!error) {
         p = mm_strip_tag (response->str, "_OWCTI:");
-        if (owcti_to_mm (*p, &owcti)) {
-            /* 3G tech always takes precedence over 2G tech */
-            if (owcti)
-                mm_callback_info_set_result (info, GUINT_TO_POINTER (owcti), NULL);
+        if (owcti_to_mm (*p, &owcti) && owcti)
+            mm_callback_info_set_result (info, GUINT_TO_POINTER (owcti), NULL);
+    }
+
+    mm_callback_info_chain_complete_one (info);
+}
+
+static void
+get_act_ossys_request_done (MMAtSerialPort *port,
+                            GString *response,
+                            GError *error,
+                            gpointer user_data)
+{
+    MMCallbackInfo *info = user_data;
+    MMModemGsmAccessTech ossys = MM_MODEM_GSM_ACCESS_TECH_UNKNOWN;
+    gboolean check_2g = TRUE, check_3g = TRUE;
+
+    /* If the modem has already been removed, return without
+     * scheduling callback */
+    if (mm_callback_info_check_modem_removed (info))
+        return;
+
+    /* If for some reason the OSSYS request failed, still try to check
+     * explicit 2G/3G mode with OCTI and OWCTI; maybe we'll get something.
+     */
+
+    if (!error) {
+        /* Response is _OSSYS: <n>,<act> so we must skip the <n> */
+        if (parse_ossys_response (response, &ossys)) {
+            mm_callback_info_set_result (info, GUINT_TO_POINTER (ossys), NULL);
+
+            /* If the OSSYS response indicated a generic access tech type
+             * then only check for more specific access tech of that type.
+             */
+            if (ossys == MM_MODEM_GSM_ACCESS_TECH_GPRS)
+                check_3g = FALSE;
+            if (ossys == MM_MODEM_GSM_ACCESS_TECH_UMTS)
+                check_2g = FALSE;
         }
     }
 
+    if (check_2g)
+        mm_at_serial_port_queue_command (port, "_OCTI?", 3, get_act_octi_request_done, info);
+    else
+        mm_callback_info_chain_complete_one (info);  /* complete it if it wasn't used */
+
+    if (check_3g)
+        mm_at_serial_port_queue_command (port, "_OWCTI?", 3, get_act_owcti_request_done, info);
+    else
+        mm_callback_info_chain_complete_one (info);  /* complete it if it wasn't used */
+
     mm_callback_info_chain_complete_one (info);
 }
 
@@ -463,7 +548,7 @@ option_get_access_technology (MMGenericGsm *modem,
     MMCallbackInfo *info;
 
     info = mm_callback_info_uint_new (MM_MODEM (modem), callback, user_data);
-    mm_callback_info_chain_start (info, 2);
+    mm_callback_info_chain_start (info, 3);
 
     port = mm_generic_gsm_get_best_at_port (modem, &info->error);
     if (!port) {
@@ -471,7 +556,6 @@ option_get_access_technology (MMGenericGsm *modem,
         return;
     }
 
-    mm_at_serial_port_queue_command (port, "_OCTI?", 3, get_act_octi_request_done, info);
-    mm_at_serial_port_queue_command (port, "_OWCTI?", 3, get_act_owcti_request_done, info);
+    mm_at_serial_port_queue_command (port, "_OSSYS?", 3, get_act_ossys_request_done, info);
 }