cmd: add clear screen 'cls' command

Add common clear screen command for configurations
CONFIG_DM_VIDEO, CONFIG_LCD and CONFIG_CFB_CONSOLE.

Remove the existing cls command implementation from
lcd.c code and activate the command for all boards
enabling CONFIG_LCD for compatibility reasons.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Tested-by: Patrick.Delaunay <patrick.delaunay@free.fr>

cmd/Kconfig

@@ -1380,6 +1380,14 @@ config CMD_CONITRACE
 	  Enable the 'conitrace' command which displays the codes received
 	  from the console input as hexadecimal numbers.
 
+config CMD_CLS
+	bool "Enable clear screen command 'cls'"
+	depends on CFB_CONSOLE || DM_VIDEO || LCD || VIDEO
+	default y if LCD
+	help
+	  Enable the 'cls' command which clears the screen contents
+	  on video frame buffer.
+
 config CMD_DISPLAY
 	bool "Enable the 'display' command, for character displays"
 	help

cmd/Makefile

@@ -32,6 +32,7 @@ obj-$(CONFIG_CMD_BTRFS) += btrfs.o
 obj-$(CONFIG_CMD_CACHE) += cache.o
 obj-$(CONFIG_CMD_CBFS) += cbfs.o
 obj-$(CONFIG_CMD_CLK) += clk.o
+obj-$(CONFIG_CMD_CLS) += cls.o
 obj-$(CONFIG_CMD_CONFIG) += config.o
 obj-$(CONFIG_CMD_CONITRACE) += conitrace.o
 obj-$(CONFIG_CMD_CONSOLE) += console.o

cmd/cls.c

@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2018
+ * DENX Software Engineering, Anatolij Gustschin <agust@denx.de>
+ *
+ * cls - clear screen command
+ */
+#include <common.h>
+#include <command.h>
+#include <dm.h>
+#include <lcd.h>
+#include <video.h>
+
+static int do_video_clear(cmd_tbl_t *cmdtp, int flag, int argc,
+			  char *const argv[])
+{
+#if defined(CONFIG_DM_VIDEO)
+	struct udevice *dev;
+
+	if (uclass_first_device_err(UCLASS_VIDEO, &dev))
+		return CMD_RET_FAILURE;
+
+	if (video_clear(dev))
+		return CMD_RET_FAILURE;
+#elif defined(CONFIG_CFB_CONSOLE)
+	video_clear();
+#elif defined(CONFIG_LCD)
+	lcd_clear();
+#else
+	return CMD_RET_FAILURE;
+#endif
+	return CMD_RET_SUCCESS;
+}
+
+U_BOOT_CMD(cls,	1, 1, do_video_clear, "clear screen", "");

common/lcd.c

@@ -242,14 +242,6 @@ void lcd_clear(void)
 	lcd_sync();
 }
 
-static int do_lcd_clear(cmd_tbl_t *cmdtp, int flag, int argc,
-			char *const argv[])
-{
-	lcd_clear();
-	return 0;
-}
-U_BOOT_CMD(cls,	1, 1, do_lcd_clear, "clear screen", "");
-
 static int lcd_init(void *lcdbase)
 {
 	debug("[LCD] Initializing LCD frambuffer at %p\n", lcdbase);