tty: vt: change consw::con_set_origin() return type

The return value of consw::con_set_origin() is only true/false, meaining
if vc->vc_origin is set to vc->vc_screenbuf or not.

So switch the type and returned values accordingly.

And document the hook.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-39-jirislaby@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/video/console/vgacon.c

@@ -65,7 +65,7 @@ static struct vgastate vgastate;
  *  Interface used by the world
  */
 
-static int vgacon_set_origin(struct vc_data *c);
+static bool vgacon_set_origin(struct vc_data *c);
 
 static struct uni_pagedict *vgacon_uni_pagedir;
 static int vgacon_refcount;
@@ -1100,15 +1100,15 @@ static int vgacon_resize(struct vc_data *c, unsigned int width,
 	return 0;
 }
 
-static int vgacon_set_origin(struct vc_data *c)
+static bool vgacon_set_origin(struct vc_data *c)
 {
 	if (vga_is_gfx ||	/* We don't play origin tricks in graphic modes */
 	    (console_blanked && !vga_palette_blanked))	/* Nor we write to blanked screens */
-		return 0;
+		return false;
 	c->vc_origin = c->vc_visible_origin = vga_vram_base;
 	vga_set_mem_top(c);
 	vga_rolled_over = 0;
-	return 1;
+	return true;
 }
 
 static void vgacon_save_screen(struct vc_data *c)

include/linux/console.h

@@ -55,6 +55,9 @@ enum vc_intensity;
  * @con_set_palette: sets the palette of the console to @table (optional)
  * @con_scrolldelta: the contents of the console should be scrolled by @lines.
  *		     Invoked by user. (optional)
+ * @con_set_origin: set origin (see &vc_data::vc_origin) of the @vc. If not
+ *		provided or returns false, the origin is set to
+ *		@vc->vc_screenbuf. (optional)
  */
 struct consw {
 	struct module *owner;
@@ -87,7 +90,7 @@ struct consw {
 	void	(*con_set_palette)(struct vc_data *vc,
 			const unsigned char *table);
 	void	(*con_scrolldelta)(struct vc_data *vc, int lines);
-	int	(*con_set_origin)(struct vc_data *vc);
+	bool	(*con_set_origin)(struct vc_data *vc);
 	void	(*con_save_screen)(struct vc_data *vc);
 	u8	(*con_build_attr)(struct vc_data *vc, u8 color,
 			enum vc_intensity intensity,