[PATCH i-g-t v2 40/43] lib/vkms: Test changing enabled device CRTCs

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

Test that, once a VKMS device is enabled, the CRTC values can't change
and that deleting it or the attached planes/encoders doesn't change the
VKMS device.

Signed-off-by: José Expósito <jose.exposito89@gmail.com>
---
 lib/igt_vkms.c             | 12 +++++++++
 lib/igt_vkms.h             |  1 +
 tests/vkms/vkms_configfs.c | 55 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 68 insertions(+)

diff --git a/lib/igt_vkms.c b/lib/igt_vkms.c
index 96f13d628..5923e8527 100644
--- a/lib/igt_vkms.c
+++ b/lib/igt_vkms.c
@@ -804,6 +804,18 @@ void igt_vkms_device_add_crtc(igt_vkms_t *dev, const char *name)
 	add_pipeline_item(dev, VKMS_PIPELINE_ITEM_CRTC, name);
 }
 
+/**
+ * igt_vkms_device_remove_crtc:
+ * @dev: Device to remove the CRTC from
+ * @name: CRTC name
+ *
+ * Remove an existing CRTC from the VKMS device.
+ */
+bool igt_vkms_device_remove_crtc(igt_vkms_t *dev, const char *name)
+{
+	return remove_pipeline_item(dev, VKMS_PIPELINE_ITEM_CRTC, name);
+}
+
 /**
  * igt_vkms_crtc_is_writeback_enabled:
  * @dev: Device the CRTC belongs to
diff --git a/lib/igt_vkms.h b/lib/igt_vkms.h
index 786db224e..9785a64e9 100644
--- a/lib/igt_vkms.h
+++ b/lib/igt_vkms.h
@@ -105,6 +105,7 @@ bool igt_vkms_plane_detach_crtc(igt_vkms_t *dev, const char *plane_name,
 				const char *crtc_name);
 
 void igt_vkms_device_add_crtc(igt_vkms_t *dev, const char *name);
+bool igt_vkms_device_remove_crtc(igt_vkms_t *dev, const char *name);
 bool igt_vkms_crtc_is_writeback_enabled(igt_vkms_t *dev, const char *name);
 void igt_vkms_crtc_set_writeback_enabled(igt_vkms_t *dev, const char *name,
 					 bool writeback);
diff --git a/tests/vkms/vkms_configfs.c b/tests/vkms/vkms_configfs.c
index 11dea86ed..62dfb99be 100644
--- a/tests/vkms/vkms_configfs.c
+++ b/tests/vkms/vkms_configfs.c
@@ -1635,6 +1635,60 @@ static void test_enabled_plane_cannot_change(void)
 	igt_vkms_device_destroy(dev);
 }
 
+/**
+ * SUBTEST: enabled-crtc-cannot-change
+ * Description: Test that, once a VKMS device is enabled, the CRTC values can't
+ *              change and that deleting it or the attached planes/encoders
+ *              doesn't change the VKMS device.
+ */
+
+static void test_enabled_crtc_cannot_change(void)
+{
+	igt_vkms_t *dev;
+
+	igt_vkms_config_t cfg = {
+		.device_name = __func__,
+		.planes = {
+			{
+				.name = "plane0",
+				.type = DRM_PLANE_TYPE_PRIMARY,
+				.possible_crtcs = { "crtc0"},
+			},
+		},
+		.crtcs = {
+			{ .name = "crtc0", .writeback = true },
+		},
+		.encoders = {
+			{ .name = "encoder0", .possible_crtcs = { "crtc0" } },
+		},
+		.connectors = {
+			{
+				.name = "connector0",
+				.possible_encoders = { "encoder0" },
+			},
+		},
+	};
+
+	dev = igt_vkms_device_create_from_config(&cfg);
+	igt_assert(dev);
+
+	igt_vkms_device_set_enabled(dev, true);
+	igt_assert(igt_vkms_device_is_enabled(dev));
+	assert_device_config(&cfg);
+
+	/* Try to change values */
+	igt_vkms_crtc_set_writeback_enabled(dev, "crtc0", false);
+	igt_assert(igt_vkms_crtc_is_writeback_enabled(dev, "crtc0"));
+
+	/* Deleting pipeline items doesn't affect the device */
+	igt_assert(igt_vkms_plane_detach_crtc(dev, "plane0", "crtc0"));
+	igt_assert(igt_vkms_encoder_detach_crtc(dev, "encoder0", "crtc0"));
+	igt_assert(igt_vkms_device_remove_crtc(dev, "crtc0"));
+	assert_device_config(&cfg);
+
+	igt_vkms_device_destroy(dev);
+}
+
 igt_main
 {
 	struct {
@@ -1676,6 +1730,7 @@ igt_main
 		{ "enable-no-connectors", test_enable_no_connectors },
 		{ "enable-too-many-connectors", test_enable_too_many_connectors },
 		{ "enabled-plane-cannot-change", test_enabled_plane_cannot_change },
+		{ "enabled-crtc-cannot-change", test_enabled_crtc_cannot_change },
 	};
 
 	igt_fixture {
-- 
2.48.1