[PATCH] lib/igt_kms: Do not treat writeback and virtual connectors as connected

Writeback and virtual connectors (e.g. DRM_MODE_CONNECTOR_WRITEBACK and
DRM_MODE_CONNECTOR_VIRTUAL) do not represent physical display sinks and
cannot be modeset using standard CRTC / atomic commit operations without
configuring a writeback output framebuffer (WRITEBACK_FB_ID).

On drivers such as MSM, writeback connectors (e.g. Virtual-1, Virtual-2)
report connected status with virtual modes. When generic KMS tests iterate
over connected outputs via for_each_connected_output() or during initial
display setup in igt_display_init(), attempting standard modesets on these
connectors causes failures (-EINVAL) before test execution can begin.

Exclude DRM_MODE_CONNECTOR_WRITEBACK and DRM_MODE_CONNECTOR_VIRTUAL in
igt_output_is_connected() so generic KMS tests only target standard
physical display outputs, while dedicated writeback tests can continue to
iterate all outputs explicitly via for_each_output().

Signed-off-by: Mark Yacoub <[email protected]>
---
 lib/igt_kms.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/igt_kms.h b/lib/igt_kms.h
index 521a03c01..8d4d14847 100644
--- a/lib/igt_kms.h
+++ b/lib/igt_kms.h
@@ -668,6 +668,10 @@ static inline bool igt_output_is_connected(igt_output_t *output)
 	    !output->config.connector->count_modes)
 		return false;
 
+	if (output->config.connector->connector_type == DRM_MODE_CONNECTOR_WRITEBACK ||
+	    output->config.connector->connector_type == DRM_MODE_CONNECTOR_VIRTUAL)
+		return false;
+
 	if (output->config.connector->connection == DRM_MODE_CONNECTED)
 		return true;
 
-- 
2.55.0.737.g08866a6d13-goog