drm/tests: Add HDMI connector rate filter hook tests

The previous patch adds a new hook for HDMI connectors to filter out
configurations based on the TMDS character rate. Let's add some tests to
make sure it works as expected.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527-kms-hdmi-connector-state-v15-14-c5af16c3aae2@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>

diff --git a/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c b/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c
index 23449a4786ce2630a86bfb0988a6c44679a98189..3601b3f7ed02413f5c5b9df6b583b29ccfecec26 100644 (file)
--- a/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c
+++ b/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c
@@ -115,6 +115,18 @@ static int set_connector_edid(struct kunit *test, struct drm_connector *connecto
 static const struct drm_connector_hdmi_funcs dummy_connector_hdmi_funcs = {
 };
 
+static enum drm_mode_status
+reject_connector_tmds_char_rate_valid(const struct drm_connector *connector,
+                                     const struct drm_display_mode *mode,
+                                     unsigned long long tmds_rate)
+{
+       return MODE_BAD;
+}
+
+static const struct drm_connector_hdmi_funcs reject_connector_hdmi_funcs = {
+       .tmds_char_rate_valid   = reject_connector_tmds_char_rate_valid,
+};
+
 static int dummy_connector_get_modes(struct drm_connector *connector)
 {
        struct drm_atomic_helper_connector_hdmi_priv *priv =
@@ -493,7 +505,60 @@ static void drm_test_check_tmds_char_rate_rgb_12bpc(struct kunit *test)
        KUNIT_EXPECT_EQ(test, conn_state->hdmi.tmds_char_rate, preferred->clock * 1500);
 }
 
+/*
+ * Test that if we filter a rate through our hook, it's indeed rejected
+ * by the whole atomic_check logic.
+ *
+ * We do so by first doing a commit on the pipeline to make sure that it
+ * works, change the HDMI helpers pointer, and then try the same commit
+ * again to see if it fails as it should.
+ */
+static void drm_test_check_hdmi_funcs_reject_rate(struct kunit *test)
+{
+       struct drm_atomic_helper_connector_hdmi_priv *priv;
+       struct drm_modeset_acquire_ctx *ctx;
+       struct drm_atomic_state *state;
+       struct drm_display_mode *preferred;
+       struct drm_crtc_state *crtc_state;
+       struct drm_connector *conn;
+       struct drm_device *drm;
+       struct drm_crtc *crtc;
+       int ret;
+
+       priv = drm_atomic_helper_connector_hdmi_init(test,
+                                                    BIT(HDMI_COLORSPACE_RGB),
+                                                    8);
+       KUNIT_ASSERT_NOT_NULL(test, priv);
+
+       ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+       KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
+       conn = &priv->connector;
+       preferred = find_preferred_mode(conn);
+       KUNIT_ASSERT_NOT_NULL(test, preferred);
+
+       drm = &priv->drm;
+       crtc = priv->crtc;
+       ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
+       KUNIT_ASSERT_EQ(test, ret, 0);
+
+       /* You shouldn't be doing that at home. */
+       conn->hdmi.funcs = &reject_connector_hdmi_funcs;
+
+       state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
+       KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
+
+       crtc_state = drm_atomic_get_crtc_state(state, crtc);
+       KUNIT_ASSERT_NOT_ERR_OR_NULL(test, crtc_state);
+
+       crtc_state->connectors_changed = true;
+
+       ret = drm_atomic_check_only(state);
+       KUNIT_EXPECT_LT(test, ret, 0);
+}
+
 static struct kunit_case drm_atomic_helper_connector_hdmi_check_tests[] = {
+       KUNIT_CASE(drm_test_check_hdmi_funcs_reject_rate),
        KUNIT_CASE(drm_test_check_output_bpc_crtc_mode_changed),
        KUNIT_CASE(drm_test_check_output_bpc_crtc_mode_not_changed),
        KUNIT_CASE(drm_test_check_tmds_char_rate_rgb_8bpc),