Applied patch from Jochen Friedrich to correct the UDev discovery.

The UDev discovery looked for known USB devices and guessed what the device
path would be. Patch fixes this to look for tty devices, and works back to
check if their parent device is a known GPS device.

Fixes: FDO#41673

1 files changed, 54 insertions, 22 deletions

diff --git a/src/gypsy-discovery.c b/src/gypsy-discovery.c
index 643b7cb..6735468 100644
--- a/src/gypsy-discovery.c
+++ b/src/gypsy-discovery.c
@@ -309,17 +309,12 @@ setup_bluetooth_discovery (GypsyDiscovery *discovery)
 struct ProductMap {
 	char *product_id;
 	char *product_name;
-	char *device_path;
 };
 
-/* This is a bit jury rigged really, but UDev doesn't appear to know the
-   tty devices that these devices use
-   Issues: Multiple GPS devices will appear as ttyACMn rather than always
-   as ttyACM0. */
 static struct ProductMap known_ids[] = {
-	{ "e8d/3329/100", "MTK GPS Receiver", "/dev/ttyACM0" },
-	{ "1546/1a4/100", "u-blox AG ANTARIS r4 GPS Receiver", "/dev/ttyACM0" },
-	{ NULL, NULL, NULL }
+	{ "e8d/3329/100", "MTK GPS Receiver" },
+	{ "1546/1a4/100", "u-blox AG ANTARIS r4 GPS Receiver" },
+	{ NULL, NULL }
 };
 
 static const char *
@@ -327,16 +322,32 @@ maybe_add_device (GypsyDiscovery *discovery,
 		  GUdevDevice    *device)
 {
 	GypsyDiscoveryPrivate *priv = discovery->priv;
-	const char *property_id, *property_type;
+	GUdevDevice *parent;
+	const char *property_id, *property_type, *name;
 	int i;
 
-	property_type = g_udev_device_get_property (device, "DEVTYPE");
+	name = g_udev_device_get_device_file (device);
+	if (name == NULL) {
+		return NULL;
+	}
+
+	/* Get USB interface */
+	parent = g_udev_device_get_parent (device);
+	if (parent == NULL)
+		return NULL;
+
+	/* Get USB device */
+	parent = g_udev_device_get_parent (parent);
+	if (parent == NULL)
+		return NULL;
+
+	property_type = g_udev_device_get_property (parent, "DEVTYPE");
 	if (property_type == NULL ||
 	    g_str_equal (property_type, "usb_device") == FALSE) {
 		return NULL;
 	}
 
-	property_id = g_udev_device_get_property (device, "PRODUCT");
+	property_id = g_udev_device_get_property (parent, "PRODUCT");
 	if (property_id == NULL) {
 		return NULL;
 	}
@@ -346,11 +357,11 @@ maybe_add_device (GypsyDiscovery *discovery,
 				 known_ids[i].product_id)) {
 			GYPSY_NOTE (DISCOVERY, "Found %s - %s",
 				    known_ids[i].product_name,
-				    known_ids[i].device_path);
+				    name);
 			g_ptr_array_add (priv->known_devices,
-					 g_strdup (known_ids[i].device_path));
+					 g_strdup (name));
 
-			return known_ids[i].device_path;
+			return name;
 		}
 	}
 
@@ -380,16 +391,37 @@ maybe_remove_device (GypsyDiscovery *discovery,
 		     GUdevDevice    *device)
 {
 	GypsyDiscoveryPrivate *priv = discovery->priv;
-	const char *property_id, *property_type;
+	const char *property_id, *property_type, *name;
+	GUdevDevice *parent;
 	int i;
 
-	property_type = g_udev_device_get_property (device, "DEVTYPE");
+	name = g_udev_device_get_device_file (device);
+	if (name == NULL) {
+		return NULL;
+	}
+
+	/* Get tty device */
+	parent = g_udev_device_get_parent (device);
+	if (parent == NULL)
+		return NULL;
+
+	/* Get USB interface */
+	parent = g_udev_device_get_parent (parent);
+	if (parent == NULL)
+		return NULL;
+
+	/* Get USB device */
+	parent = g_udev_device_get_parent (parent);
+	if (parent == NULL)
+		return NULL;
+
+	property_type = g_udev_device_get_property (parent, "DEVTYPE");
 	if (property_type == NULL ||
 	    g_str_equal (property_type, "usb_device") == FALSE) {
 		return NULL;
 	}
 
-	property_id = g_udev_device_get_property (device, "PRODUCT");
+	property_id = g_udev_device_get_property (parent, "PRODUCT");
 	if (property_id == NULL) {
 		return NULL;
 	}
@@ -399,11 +431,11 @@ maybe_remove_device (GypsyDiscovery *discovery,
 				 known_ids[i].product_id)) {
 			GYPSY_NOTE (DISCOVERY, "Found %s - %s",
 				    known_ids[i].product_name,
-				    known_ids[i].device_path);
+				    name);
 			remove_string_from_array (priv->known_devices,
-						  known_ids[i].device_path);
+						  name);
 
-			return known_ids[i].device_path;
+			return name;
 		}
 	}
 
@@ -449,7 +481,7 @@ add_known_udev_devices (GypsyDiscovery *self)
 	GypsyDiscoveryPrivate *priv = self->priv;
 	GList *udev_devices = NULL, *l;
 
-	udev_devices = g_udev_client_query_by_subsystem (priv->client, "usb");
+	udev_devices = g_udev_client_query_by_subsystem (priv->client, "tty");
 	for (l = udev_devices; l; l = l->next) {
 		GUdevDevice *device = l->data;
 
@@ -464,7 +496,7 @@ static void
 gypsy_discovery_init (GypsyDiscovery *self)
 {
         GypsyDiscoveryPrivate *priv = GET_PRIVATE (self);
-        const char * const subsystems[] = { "usb" };
+        const char * const subsystems[] = { "tty" };
 
         self->priv = priv;