[PATCH i-g-t v1] tests/kms_properties: Add skip on headless machines

[sumit kishore <sumit.kishore@intel.com>]

Print debug messages for sub-tests which are expected to
skip on headless display systems.

Signed-off-by: sumit kishore <sumit.kishore@intel.com>
---
 tests/kms_properties.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/tests/kms_properties.c b/tests/kms_properties.c
index 86d05c6d4..01f0d5867 100644
--- a/tests/kms_properties.c
+++ b/tests/kms_properties.c
@@ -73,6 +73,19 @@ struct additional_test {
 			  uint32_t prop_id, uint64_t prop_value, bool atomic);
 };
 
+static void is_headless_display(igt_display_t *display)
+{
+	igt_output_t *output;
+	bool display_connected = false;
+
+	for_each_connected_output(display, output) {
+		display_connected = true;
+		break;
+	}
+
+	igt_skip_on_f(!display_connected, "No active display connected, skipping sub-test\n");
+}
+
 static void prepare_pipe(igt_display_t *display, igt_crtc_t *crtc,
 			 igt_output_t *output, struct igt_fb *fb)
 {
@@ -377,6 +390,8 @@ static void plane_properties(igt_display_t *display, bool atomic)
 	igt_output_t *output;
 	igt_crtc_t *crtc;
 
+	is_headless_display(display);
+
 	for_each_crtc_with_single_output(display, crtc, output) {
 		igt_display_reset(display);
 
@@ -400,6 +415,8 @@ static void crtc_properties(igt_display_t *display, bool atomic)
 	igt_crtc_t *crtc;
 	igt_output_t *output;
 
+	is_headless_display(display);
+
 	for_each_crtc_with_single_output(display, crtc, output) {
 		igt_display_reset(display);
 
-- 
2.43.0