drm/tests: Add tests for the new Monochrome value of tv_mode

Adds test for the cmdline parser, connector property, and
drm_analog_tv_mode to ensure the behaviour of the new value is
correct.
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240620110947.3615207-1-dave.stevenson@raspberrypi.com

drivers/gpu/drm/tests/drm_cmdline_parser_test.c

@@ -992,6 +992,17 @@ static const struct drm_cmdline_tv_option_test drm_cmdline_tv_option_tests[] = {
 	TV_OPT_TEST(PAL_M, "720x480i,tv_mode=PAL-M", drm_mode_analog_ntsc_480i),
 	TV_OPT_TEST(PAL_N, "720x576i,tv_mode=PAL-N", drm_mode_analog_pal_576i),
 	TV_OPT_TEST(SECAM, "720x576i,tv_mode=SECAM", drm_mode_analog_pal_576i),
+	{
+		.name = "MONO_525",
+		.cmdline = "720x480i,tv_mode=Mono",
+		.mode_fn = drm_mode_analog_ntsc_480i,
+		.tv_mode = DRM_MODE_TV_MODE_MONOCHROME,
+	}, {
+		.name = "MONO_625",
+		.cmdline = "720x576i,tv_mode=Mono",
+		.mode_fn = drm_mode_analog_pal_576i,
+		.tv_mode = DRM_MODE_TV_MODE_MONOCHROME,
+	},
 };
 
 static void drm_cmdline_tv_option_desc(const struct drm_cmdline_tv_option_test *t,

drivers/gpu/drm/tests/drm_connector_test.c

@@ -777,6 +777,7 @@ struct drm_get_tv_mode_from_name_test drm_get_tv_mode_from_name_valid_tests[] =
 	TV_MODE_NAME("PAL-M", DRM_MODE_TV_MODE_PAL_M),
 	TV_MODE_NAME("PAL-N", DRM_MODE_TV_MODE_PAL_N),
 	TV_MODE_NAME("SECAM", DRM_MODE_TV_MODE_SECAM),
+	TV_MODE_NAME("Mono", DRM_MODE_TV_MODE_MONOCHROME),
 };
 
 static void

drivers/gpu/drm/tests/drm_modes_test.c

@@ -130,7 +130,38 @@ static void drm_test_modes_analog_tv_pal_576i_inlined(struct kunit *test)
 	KUNIT_EXPECT_TRUE(test, drm_mode_equal(expected, mode));
 }
 
+static void drm_test_modes_analog_tv_mono_576i(struct kunit *test)
+{
+	struct drm_test_modes_priv *priv = test->priv;
+	struct drm_display_mode *mode;
+
+	mode = drm_analog_tv_mode(priv->drm,
+				  DRM_MODE_TV_MODE_MONOCHROME,
+				  13500 * HZ_PER_KHZ, 720, 576,
+				  true);
+	KUNIT_ASSERT_NOT_NULL(test, mode);
+
+	KUNIT_EXPECT_EQ(test, drm_mode_vrefresh(mode), 50);
+	KUNIT_EXPECT_EQ(test, mode->hdisplay, 720);
+
+	/* BT.601 defines hsync_start at 732 for 576i */
+	KUNIT_EXPECT_EQ(test, mode->hsync_start, 732);
+
+	/*
+	 * The PAL standard expects a line to take 64us. With a pixel
+	 * clock of 13.5 MHz, a pixel takes around 74ns, so we need to
+	 * have 64000ns / 74ns = 864.
+	 *
+	 * This is also mandated by BT.601.
+	 */
+	KUNIT_EXPECT_EQ(test, mode->htotal, 864);
+
+	KUNIT_EXPECT_EQ(test, mode->vdisplay, 576);
+	KUNIT_EXPECT_EQ(test, mode->vtotal, 625);
+}
+
 static struct kunit_case drm_modes_analog_tv_tests[] = {
+	KUNIT_CASE(drm_test_modes_analog_tv_mono_576i),
 	KUNIT_CASE(drm_test_modes_analog_tv_ntsc_480i),
 	KUNIT_CASE(drm_test_modes_analog_tv_ntsc_480i_inlined),
 	KUNIT_CASE(drm_test_modes_analog_tv_pal_576i),