1 files changed, 90 insertions, 27 deletions

diff --git a/src/tdm_backend_drm.c b/src/tdm_backend_drm.c
index d6e420e..931fda6 100644
--- a/src/tdm_backend_drm.c
+++ b/src/tdm_backend_drm.c
@@ -43,8 +43,52 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #define TDM_DRM_NAME "vigs"
 
 #ifdef HAVE_UDEV
+static int
+_tdm_drm_is_kms(struct udev_device *device)
+{
+	drmModeRes *res;
+	int fd = -1, id = -1;
+	const char *file_name;
+	const char *sys_num;
+
+	file_name = udev_device_get_devnode(device);
+	if (!file_name) return 0;
+
+	TDM_BACKEND_INFO("check kms device:%s", file_name);
+
+	sys_num = udev_device_get_sysnum(device);
+	if (!sys_num) return 0;
+
+	id = atoi(sys_num);
+	if (id < 0) return 0;
+
+	fd = open(file_name, O_RDWR | O_CLOEXEC);
+	if (fd < 0) {
+		TDM_BACKEND_ERR("fail to open drm device(%s)", file_name);
+		return 0;
+	}
+
+	res = drmModeGetResources(fd);
+	if (!res) goto fail;
+
+	if ((res->count_crtcs <= 0) || (res->count_connectors <= 0) ||
+		(res->count_encoders <= 0))
+		goto fail;
+
+	close(fd);
+	drmModeFreeResources(res);
+
+	return 1;
+
+fail:
+	if (fd >= 0) close(fd);
+	if (res) drmModeFreeResources(res);
+
+	return 0;
+}
+
 static struct udev_device *
-_tdm_find_primary_gpu(void)
+_tdm_drm_find_primary_gpu(void)
 {
 	struct udev *udev;
 	struct udev_enumerate *e;
@@ -65,6 +109,8 @@ _tdm_find_primary_gpu(void)
 	udev_enumerate_scan_devices(e);
 	drm_device = NULL;
 	udev_list_entry_foreach(entry, udev_enumerate_get_list_entry(e)) {
+		int is_boot_vga;
+
 		path = udev_list_entry_get_name(entry);
 		device = udev_device_new_from_syspath(udev, path);
 		if (!device)
@@ -74,21 +120,32 @@ _tdm_find_primary_gpu(void)
 						"pci", NULL);
 		if (pci) {
 			id = udev_device_get_sysattr_value(pci, "boot_vga");
-			if (id && !strcmp(id, "1")) {
-				if (drm_device)
-					udev_device_unref(drm_device);
-				drm_device = device;
-				break;
-			}
+			if (id && !strcmp(id, "1"))
+				is_boot_vga = 1;
 		}
 
-		if (!drm_device)
-			drm_device = device;
-		else
+		if (!is_boot_vga && drm_device) {
+			udev_device_unref(device);
+			continue;
+		}
+
+		if (!_tdm_drm_is_kms(device)) {
 			udev_device_unref(device);
+			continue;
+		}
+
+		if (is_boot_vga) {
+			if (drm_device)
+				udev_device_unref(drm_device);
+			drm_device = device;
+			break;
+		}
+
+		drm_device = device;
 	}
 
 	udev_enumerate_unref(e);
+
 	return drm_device;
 }
 
@@ -190,31 +247,37 @@ _tdm_drm_open_drm(void)
 
 	fd = drmOpen(TDM_DRM_NAME, NULL);
 	if (fd < 0)
-		TDM_BACKEND_WRN("Cannot open '%s' drm", TDM_DRM_NAME);
+		TDM_BACKEND_WRN("fail to open '%s' drm", TDM_DRM_NAME);
 
 #ifdef HAVE_UDEV
+	struct udev_device *drm_device = NULL;
+	const char *file_name;
+
 	if (fd < 0) {
-		struct udev_device *drm_device = NULL;
-		const char *filename;
-		TDM_BACKEND_WRN("Cannot open drm device.. search by udev");
-
-		drm_device = _tdm_find_primary_gpu();
-		if (drm_device == NULL) {
-			TDM_BACKEND_ERR("fail to find drm device\n");
-			goto close_l;
-		}
+		TDM_BACKEND_WRN("fail to open drm device.. search by udev");
 
-		filename = udev_device_get_devnode(drm_device);
+		drm_device = _tdm_drm_find_primary_gpu();
+		if (!drm_device) {
+			TDM_BACKEND_ERR("fail to find drm device");
+			goto ret;
+		}
 
-		fd = open(filename, O_RDWR | O_CLOEXEC);
-		if (fd < 0)
-			TDM_BACKEND_ERR("Cannot open drm device(%s)\n", filename);
+		file_name = udev_device_get_devnode(drm_device);
+		if (!file_name) {
+			TDM_BACKEND_ERR("fail to get devnode");
+			goto ret;
+		}
 
-		TDM_BACKEND_DBG("open drm device (name:%s, fd:%d)", filename, fd);
+		fd = open(file_name, O_RDWR | O_CLOEXEC);
+		if (fd < 0) {
+			TDM_BACKEND_ERR("fail to open drm device(%s)", file_name);
+			goto ret;
+		}
 
-		udev_device_unref(drm_device);
+		TDM_BACKEND_INFO("open drm device (name:%s fd:%d)", file_name, fd);
 	}
-close_l:
+ret:
+	if (drm_device) udev_device_unref(drm_device);
 #endif
 	return fd;
 }