[PATCH i-g-t 11/39] lib/vkms: Test CRTC default values

[José Expósito]

Add a helper to get the CRTC writeback status and test that the default
value is set when a new CRTC is created.

Signed-off-by: José Expósito <jose.exposito89 at gmail.com>
---
 lib/igt_vkms.c             | 19 +++++++++++++++++++
 lib/igt_vkms.h             |  1 +
 tests/vkms/vkms_configfs.c | 20 ++++++++++++++++++++
 3 files changed, 40 insertions(+)

diff --git a/lib/igt_vkms.c b/lib/igt_vkms.c
index a7dad43e2..4021f9aea 100644
--- a/lib/igt_vkms.c
+++ b/lib/igt_vkms.c
@@ -24,6 +24,7 @@
 #define VKMS_ROOT_DIR_NAME		"vkms"
 #define VKMS_FILE_ENABLED		"enabled"
 #define VKMS_FILE_PLANE_TYPE		"type"
+#define VKMS_FILE_CRTC_WRITEBACK	"writeback"
 
 enum vkms_pipeline_item {
 	VKMS_PIPELINE_ITEM_PLANE,
@@ -377,3 +378,21 @@ void igt_vkms_device_add_crtc(igt_vkms_t *dev, const char *name)
 {
 	add_pipeline_item(dev, VKMS_PIPELINE_ITEM_CRTC, name);
 }
+
+/**
+ * igt_vkms_crtc_is_writeback_enabled:
+ * @dev: Device the CRTC belongs to
+ * @name: CRTC name
+ *
+ * Indicate whether a VKMS CRTC writeback connector is enabled or not.
+ */
+bool igt_vkms_crtc_is_writeback_enabled(igt_vkms_t *dev, const char *name)
+{
+	char path[PATH_MAX];
+
+	snprintf(path, sizeof(path), "%s/%s/%s/%s", dev->path,
+		 get_pipeline_item_dir_name(VKMS_PIPELINE_ITEM_CRTC), name,
+		 VKMS_FILE_CRTC_WRITEBACK);
+
+	return read_bool(path);
+}
diff --git a/lib/igt_vkms.h b/lib/igt_vkms.h
index 7f70f92d3..59f6a9775 100644
--- a/lib/igt_vkms.h
+++ b/lib/igt_vkms.h
@@ -34,5 +34,6 @@ int igt_vkms_plane_get_type(igt_vkms_t *dev, const char *name);
 void igt_vkms_plane_set_type(igt_vkms_t *dev, const char *name, int type);
 
 void igt_vkms_device_add_crtc(igt_vkms_t *dev, const char *name);
+bool igt_vkms_crtc_is_writeback_enabled(igt_vkms_t *dev, const char *name);
 
 #endif /* __IGT_VKMS_H__ */
diff --git a/tests/vkms/vkms_configfs.c b/tests/vkms/vkms_configfs.c
index 398232c03..95779d336 100644
--- a/tests/vkms/vkms_configfs.c
+++ b/tests/vkms/vkms_configfs.c
@@ -300,6 +300,25 @@ static void test_crtc_default_files(void)
 	igt_vkms_device_destroy(dev);
 }
 
+/**
+ * SUBTEST: crtc-default-values
+ * Description: Check that the default values for the CRTC are correct.
+ */
+
+static void test_crtc_default_values(void)
+{
+	igt_vkms_t *dev;
+
+	dev = igt_vkms_device_create(__func__);
+	igt_assert(dev);
+
+	igt_vkms_device_add_crtc(dev, "crtc0");
+
+	igt_assert(!igt_vkms_crtc_is_writeback_enabled(dev, "crtc0"));
+
+	igt_vkms_device_destroy(dev);
+}
+
 igt_main
 {
 	struct {
@@ -313,6 +332,7 @@ igt_main
 		{ "plane-default-values", test_plane_default_values },
 		{ "plane-wrong-values", test_plane_wrong_values },
 		{ "crtc-default-files", test_crtc_default_files },
+		{ "crtc-default-values", test_crtc_default_values },
 	};
 
 	igt_fixture {
-- 
2.48.1