[PATCH i-g-t v2 12/43] lib/vkms: Test CRTC default values

["José Expósito" <jose.exposito89@gmail.com>]

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

Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
---
 lib/igt_vkms.c             | 33 +++++++++++++++++++++++++++++++++
 lib/igt_vkms.h             |  3 +++
 tests/vkms/vkms_configfs.c | 20 ++++++++++++++++++++
 3 files changed, 56 insertions(+)

diff --git a/lib/igt_vkms.c b/lib/igt_vkms.c
index e780e4af2..0c3c9812a 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,
@@ -241,6 +242,22 @@ void igt_vkms_get_crtc_path(igt_vkms_t *dev, const char *name, char *path,
 	get_pipeline_item_path(dev, VKMS_PIPELINE_ITEM_CRTC, name, path, len);
 }
 
+/**
+ * igt_vkms_get_crtc_writeback_path:
+ * @dev: Device containing the CRTC
+ * @name: CRTC name
+ * @path: Output path
+ * @len: Maximum @path length
+ *
+ * Returns the CRTC "writeback" file path.
+ */
+void igt_vkms_get_crtc_writeback_path(igt_vkms_t *dev, const char *name,
+				      char *path, size_t len)
+{
+	get_pipeline_item_file_path(dev, VKMS_PIPELINE_ITEM_CRTC, name,
+				    VKMS_FILE_CRTC_WRITEBACK, path, len);
+}
+
 /**
  * igt_vkms_device_create:
  * @name: VKMS device name
@@ -476,3 +493,19 @@ 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];
+
+	igt_vkms_get_crtc_writeback_path(dev, name, path, sizeof(path));
+
+	return read_bool(path);
+}
diff --git a/lib/igt_vkms.h b/lib/igt_vkms.h
index d44131407..23c0560f8 100644
--- a/lib/igt_vkms.h
+++ b/lib/igt_vkms.h
@@ -29,6 +29,8 @@ void igt_vkms_get_plane_type_path(igt_vkms_t *dev, const char *name, char *path,
 				  size_t len);
 void igt_vkms_get_crtc_path(igt_vkms_t *dev, const char *name, char *path,
 			    size_t len);
+void igt_vkms_get_crtc_writeback_path(igt_vkms_t *dev, const char *name,
+				      char *path, size_t len);
 
 igt_vkms_t *igt_vkms_device_create(const char *name);
 void igt_vkms_device_destroy(igt_vkms_t *dev);
@@ -42,5 +44,6 @@ 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 ab15f29f9..7f0e07121 100644
--- a/tests/vkms/vkms_configfs.c
+++ b/tests/vkms/vkms_configfs.c
@@ -338,6 +338,25 @@ 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 {
@@ -352,6 +371,7 @@ igt_main
 		{ "plane-wrong-values", test_plane_wrong_values },
 		{ "plane-valid-values", test_plane_valid_values },
 		{ "crtc-default-files", test_crtc_default_files },
+		{ "crtc-default-values", test_crtc_default_values },
 	};
 
 	igt_fixture {
-- 
2.48.1