video: add command cls

Implement the existing command cls, for clear screen, when CONFIG_DM_VIDEO is activated.

This command was defined for old LCD framework (not dm) in
common/lcd.c:251
U_BOOT_CMD(cls, 1, 1, do_lcd_clear, "clear screen", "");

This command is useful to clear existing output (vidconsole) before to display splashscreen with bmp command.

---
Example of simple splashscreen in DISTRO script: boot.scr.uimg

if load ${devtype} ${devnum}:${distro_bootpart} ${splashimage} splash.bmp then
env set stdout "serial"
env set stderr "serial"
cls
bmp display ${splashimage}
fi

 drivers/video/video-uclass.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

index 44dfa71..5fe49a5 100644
@@ -300,3 +300,17 @@ UCLASS_DRIVER(video) = {
 	.per_device_auto_alloc_size	= sizeof(struct video_priv),
 	.per_device_platdata_auto_alloc_size = sizeof(struct video_uc_platdata),
 };
+
+static int do_video_clear(cmd_tbl_t *cmdtp, int flag, int argc,
+			  char *const argv[])
+{
+	struct udevice *dev;
+
+	if (uclass_first_device_err(UCLASS_VIDEO, &dev))
+		return CMD_RET_FAILURE;
+	video_clear(dev);
+
+	return 0;
+}
+
+U_BOOT_CMD(cls,	1, 1, do_video_clear, "clear screen", "");

2.7.4

Hi Patrick,

Thanks for the patch! But I think we should remove this existing lcd specific cls and add a common command under cmd/cls.c. I'll submit a path for this.

--
Anatolij

Hi Patrick,

On Sat, 17 Nov 2018 14:50:26 +0100
Anatolij Gustschin agust at denx.de wrote:
...

Please test using this patch [1].

[1] http://patchwork.ozlabs.org/patch/999320/

--
Anatolij

Hi Anatolij,

Hi Patrick,

I agree, that adding a new command file in cmd directory is cleaner. I hesitate to do the same when I prepare my patch.

This patchset is superseded by (1), tested on my side for DM_VIDEO configuration (stm32mp157 board).

Regards
Patrick