video: theadorable: Use RGB565 for BMP blitting

At present this uses RGB555 format for blitting to a display. Sandbox uses
565 and that seems to be more normal for BMP as well. Update the code
accordingly and add a test.

Note that this likely breaks the theadorable board so we may need to
discuss supporting both formats.

Signed-off-by: Simon Glass <sjg@chromium.org>

configs/sandbox_defconfig

@@ -286,6 +286,7 @@ CONFIG_SANDBOX_OSD=y
 CONFIG_SPLASH_SCREEN_ALIGN=y
 CONFIG_VIDEO_BMP_RLE8=y
 CONFIG_BMP_16BPP=y
+CONFIG_BMP_24BPP=y
 CONFIG_W1=y
 CONFIG_W1_GPIO=y
 CONFIG_W1_EEPROM=y

configs/sandbox_flattree_defconfig

@@ -199,6 +199,7 @@ CONFIG_OSD=y
 CONFIG_SANDBOX_OSD=y
 CONFIG_VIDEO_BMP_RLE8=y
 CONFIG_BMP_16BPP=y
+CONFIG_BMP_24BPP=y
 CONFIG_CMD_DHRYSTONE=y
 CONFIG_RSA_VERIFY_WITH_PKEY=y
 CONFIG_TPM=y

drivers/video/video_bmp.c

@@ -338,9 +338,9 @@ int video_bmp_display(struct udevice *dev, ulong bmp_image, int x, int y,
 		for (i = 0; i < height; ++i) {
 			for (j = 0; j < width; j++) {
 				if (bpix == 16) {
-					/* 16bit 555RGB format */
-					*(u16 *)fb = ((bmap[2] >> 3) << 10) |
-						((bmap[1] >> 3) << 5) |
+					/* 16bit 565RGB format */
+					*(u16 *)fb = ((bmap[2] >> 3) << 11) |
+						((bmap[1] >> 2) << 5) |
 						(bmap[0] >> 3);
 					bmap += 3;
 					fb += 2;

test/dm/video.c

@@ -363,6 +363,52 @@ static int dm_test_video_bmp16(struct unit_test_state *uts)
 }
 DM_TEST(dm_test_video_bmp16, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT);
 
+/* Test drawing a 24bpp bitmap file on a 16bpp display */
+static int dm_test_video_bmp24(struct unit_test_state *uts)
+{
+	ulong src, src_len = ~0UL;
+	uint dst_len = ~0U;
+	struct udevice *dev;
+	ulong dst = 0x10000;
+
+	ut_assertok(uclass_find_first_device(UCLASS_VIDEO, &dev));
+	ut_assertnonnull(dev);
+	ut_assertok(sandbox_sdl_set_bpp(dev, VIDEO_BPP16));
+
+	ut_assertok(read_file(uts, "tools/logos/denx-24bpp.bmp.gz", &src));
+	ut_assertok(gunzip(map_sysmem(dst, 0), dst_len, map_sysmem(src, 0),
+			   &src_len));
+
+	ut_assertok(video_bmp_display(dev, dst, 0, 0, false));
+	ut_asserteq(3656, compress_frame_buffer(uts, dev));
+
+	return 0;
+}
+DM_TEST(dm_test_video_bmp24, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT);
+
+/* Test drawing a 24bpp bitmap file on a 32bpp display */
+static int dm_test_video_bmp24_32(struct unit_test_state *uts)
+{
+	ulong src, src_len = ~0UL;
+	uint dst_len = ~0U;
+	struct udevice *dev;
+	ulong dst = 0x10000;
+
+	ut_assertok(uclass_find_first_device(UCLASS_VIDEO, &dev));
+	ut_assertnonnull(dev);
+	ut_assertok(sandbox_sdl_set_bpp(dev, VIDEO_BPP32));
+
+	ut_assertok(read_file(uts, "tools/logos/denx-24bpp.bmp.gz", &src));
+	ut_assertok(gunzip(map_sysmem(dst, 0), dst_len, map_sysmem(src, 0),
+			   &src_len));
+
+	ut_assertok(video_bmp_display(dev, dst, 0, 0, false));
+	ut_asserteq(6827, compress_frame_buffer(uts, dev));
+
+	return 0;
+}
+DM_TEST(dm_test_video_bmp24_32, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT);
+
 /* Test drawing a bitmap file on a 32bpp display */
 static int dm_test_video_bmp32(struct unit_test_state *uts)
 {