[PATCH i-g-t v10 07/49] lib/igt_kms: Add helper to get a pipe from a connector

[Louis Chauvet <louis.chauvet@bootlin.com>]

Currently there is no way to get a pipe from the connector. Add this tiny
helper that will try to get the currently used pipe for a specific
connector.

Reviewed-by: Kory Maincent <kory.maincent@bootlin.com>
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
---
 lib/igt_kms.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
 lib/igt_kms.h |  3 +++
 2 files changed, 47 insertions(+)

diff --git a/lib/igt_kms.c b/lib/igt_kms.c
index 481b556dee99..d134fd4bb80e 100644
--- a/lib/igt_kms.c
+++ b/lib/igt_kms.c
@@ -8483,3 +8483,47 @@ int kms_wait_for_new_connectors(uint32_t **newly_connected,
 
 	return newly_connected_count;
 }
+
+/**
+ * igt_get_crtc_index_from_connector_id() - Get a pipe from the connector id
+ * @drm_fd: drm file descriptor to which the connector belongs
+ * @connector_id: connector to inspect
+ *
+ * Assert if:
+ * - CRTC_ID property is not found
+ * - CRTC_ID property don't have the DRM_MODE_PROP_OBJECT flag
+ * Returns: 0 if the connector is not connected to any pipe
+ */
+int igt_get_crtc_index_from_connector_id(int drm_fd, int connector_id)
+{
+	drmModeObjectPropertiesPtr proplist;
+	drmModePropertyPtr crtc_id_prop;
+	drmModePropertyPtr prop;
+	int crtc_index;
+	uint32_t crtc_id;
+	int i;
+
+	proplist = drmModeObjectGetProperties(drm_fd, connector_id, DRM_MODE_OBJECT_CONNECTOR);
+	crtc_id_prop = NULL;
+
+	for (i = 0; i < proplist->count_props; i++) {
+		prop = drmModeGetProperty(drm_fd, proplist->props[i]);
+
+		if (strcmp(prop->name, "CRTC_ID") == 0) {
+			crtc_id_prop = prop;
+			break;
+		}
+		drmModeFreeProperty(prop);
+	}
+
+	igt_assert(crtc_id_prop);
+	igt_assert((crtc_id_prop->flags & DRM_MODE_PROP_EXTENDED_TYPE) == DRM_MODE_PROP_OBJECT);
+	crtc_id = proplist->prop_values[i];
+	drmModeFreeProperty(crtc_id_prop);
+	drmModeFreeObjectProperties(proplist);
+	if (crtc_id != 0) {
+		crtc_index = kmstest_get_crtc_index_from_id(drm_fd, crtc_id);
+		return crtc_index;
+	}
+	return 0;
+}
diff --git a/lib/igt_kms.h b/lib/igt_kms.h
index 02f6f427f1f0..462e139c46af 100644
--- a/lib/igt_kms.h
+++ b/lib/igt_kms.h
@@ -1306,4 +1306,7 @@ int kms_wait_for_new_connectors(uint32_t **newly_connected,
 int
 get_array_diff(const uint32_t *array_a, int array_a_len, const uint32_t *array_b, int array_b_len,
 	       uint32_t **diff);
+
+int igt_get_crtc_index_from_connector_id(int drm_fd, int connector_id);
+
 #endif /* __IGT_KMS_H__ */

-- 
2.52.0