modem-helpers-qmi: better handle no supported modes

Dell Snapdragon X62 before FCC Unlock reports no radio interfaces
from QMI and no device capabilities from MBIM. Instead of asserting
in mm_filter_supported_modes() when called from
mm_supported_modes_from_qmi_supported_modes_context() gracefully
handle the lack of supported modes.

Signed-off-by: Dan Williams <dan@ioncontrol.co>

4 files changed, 52 insertions, 14 deletions

diff --git a/src/mm-modem-helpers-qmi.c b/src/mm-modem-helpers-qmi.c
index bc0be400..7a87454b 100644
--- a/src/mm-modem-helpers-qmi.c
+++ b/src/mm-modem-helpers-qmi.c
@@ -2541,13 +2541,22 @@ mm_supported_capabilities_from_qmi_supported_capabilities_context (MMQmiSupporte
 /* Utility to build list of supported modes */
 
 GArray *
-mm_supported_modes_from_qmi_supported_modes_context (MMQmiSupportedModesContext *ctx,
-                                                     gpointer                    log_object)
+mm_supported_modes_from_qmi_supported_modes_context (MMQmiSupportedModesContext  *ctx,
+                                                     gpointer                     log_object,
+                                                     GError                     **error)
 {
     g_autoptr(GArray)       combinations = NULL;
     g_autoptr(GArray)       all = NULL;
     MMModemModeCombination  mode;
 
+    if (ctx->all == MM_MODEM_MODE_NONE) {
+        g_set_error (error,
+                     MM_CORE_ERROR,
+                     MM_CORE_ERROR_FAILED,
+                     "No supported modes reported");
+        return NULL;
+    }
+
     /* Start with a mode including ALL */
     mode.allowed = ctx->all;
     mode.preferred = MM_MODEM_MODE_NONE;
diff --git a/src/mm-modem-helpers-qmi.h b/src/mm-modem-helpers-qmi.h
index 6adb1597..75fdd5f7 100644
--- a/src/mm-modem-helpers-qmi.h
+++ b/src/mm-modem-helpers-qmi.h
@@ -217,8 +217,9 @@ typedef struct {
     MMModemCapability current_capabilities;
 } MMQmiSupportedModesContext;
 
-GArray *mm_supported_modes_from_qmi_supported_modes_context (MMQmiSupportedModesContext *ctx,
-                                                             gpointer                    log_object);
+GArray *mm_supported_modes_from_qmi_supported_modes_context (MMQmiSupportedModesContext  *ctx,
+                                                             gpointer                     log_object,
+                                                             GError                     **error);
 
 /*****************************************************************************/
 /* QMI unique id manipulation */
diff --git a/src/mm-shared-qmi.c b/src/mm-shared-qmi.c
index f6a7404d..4fd92cb0 100644
--- a/src/mm-shared-qmi.c
+++ b/src/mm-shared-qmi.c
@@ -1728,6 +1728,7 @@ mm_shared_qmi_load_supported_modes (MMIfaceModem        *self,
     MMQmiSupportedModesContext  ctx = { 0 };
     guint                       i;
     GArray                     *combinations;
+    GError                     *error = NULL;
 
     task = g_task_new (self, NULL, callback, user_data);
 
@@ -1753,8 +1754,11 @@ mm_shared_qmi_load_supported_modes (MMIfaceModem        *self,
     ctx.current_capabilities = priv->current_capabilities;
     ctx.multimode = priv->multimode;
 
-    combinations = mm_supported_modes_from_qmi_supported_modes_context (&ctx, self);
-    g_task_return_pointer (task, combinations, (GDestroyNotify) g_array_unref);
+    combinations = mm_supported_modes_from_qmi_supported_modes_context (&ctx, self, &error);
+    if (error)
+        g_task_return_error (task, error);
+    else
+        g_task_return_pointer (task, combinations, (GDestroyNotify) g_array_unref);
     g_object_unref (task);
 }
 
diff --git a/src/tests/test-modem-helpers-qmi.c b/src/tests/test-modem-helpers-qmi.c
index 7ff1c9f2..576beb68 100644
--- a/src/tests/test-modem-helpers-qmi.c
+++ b/src/tests/test-modem-helpers-qmi.c
@@ -72,14 +72,22 @@ test_supported_modes_expected (MMQmiSupportedModesContext   *ctx,
     g_autoptr(GArray)  built = NULL;
     g_autofree gchar  *expected_str = NULL;
     g_autofree gchar  *built_str = NULL;
-
-    built = mm_supported_modes_from_qmi_supported_modes_context (ctx, NULL);
-
-    expected_str = mm_common_build_mode_combinations_string (expected_modes, n_expected_modes);
-    built_str = mm_common_build_mode_combinations_string ((MMModemModeCombination *)built->data, built->len);
-
-    /* compare strings, so that the error shows the string values as well */
-    g_assert_cmpstr (built_str, ==, expected_str);
+    g_autoptr(GError)  error = NULL;
+
+    built = mm_supported_modes_from_qmi_supported_modes_context (ctx, NULL, &error);
+    if (built == NULL) {
+        g_assert_error (error, MM_CORE_ERROR, MM_CORE_ERROR_FAILED);
+        g_assert_cmpint (n_expected_modes, ==, 0);
+    } else {
+        g_assert_no_error (error);
+        g_assert_cmpint (n_expected_modes, >, 0);
+
+        expected_str = mm_common_build_mode_combinations_string (expected_modes, n_expected_modes);
+        built_str = mm_common_build_mode_combinations_string ((MMModemModeCombination *)built->data, built->len);
+
+        /* compare strings, so that the error shows the string values as well */
+        g_assert_cmpstr (built_str, ==, expected_str);
+    }
 }
 
 /*****************************************************************************/
@@ -1332,6 +1340,20 @@ test_supported_modes_generic_nr5g_lte_evdo (void)
                                    G_N_ELEMENTS (expected_modes));
 }
 
+static void
+test_supported_modes_generic_none (void)
+{
+    MMQmiSupportedModesContext ctx;
+
+    /* Dell Snapdragon X62 before FCC unlock reports no supported radio interfaces */
+    ctx.multimode = FALSE;
+    ctx.all = MM_MODEM_MODE_NONE;
+
+    test_supported_modes_expected (&ctx,
+                                   NULL,
+                                   0);
+}
+
 /*****************************************************************************/
 /* System Info processor helper */
 
@@ -1970,6 +1992,8 @@ int main (int argc, char **argv)
     g_test_add_func ("/MM/qmi/supported-capabilities/generic/nr5g-lte-evdo",  test_supported_capabilities_generic_nr5g_lte_evdo);
     g_test_add_func ("/MM/qmi/supported-modes/generic/nr5g-lte-evdo",         test_supported_modes_generic_nr5g_lte_evdo);
 
+    g_test_add_func ("/MM/qmi/supported-modes/generic/none",                  test_supported_modes_generic_none);
+
     g_test_add_func ("/MM/qmi/registration-state-from-system-info/2g/searching",     test_registration_state_from_qmi_system_info_2g_searching);
     g_test_add_func ("/MM/qmi/registration-state-from-system-info/2g/idle",          test_registration_state_from_qmi_system_info_2g_idle);
     g_test_add_func ("/MM/qmi/registration-state-from-system-info/2g/cs-home",       test_registration_state_from_qmi_system_info_2g_cs_home);