tty: vt: make types around consw::con_blank() bool

Both the mode_switch parameter and the return value (a redraw needed)
are true/false. So switch them to bool, so that users won't return
-Eerrors or anything else.

And document the hook.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-parisc@vger.kernel.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-36-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/video/console/dummycon.c

@@ -79,21 +79,21 @@ static void dummycon_putcs(struct vc_data *vc, const u16 *s, unsigned int count,
 	raw_notifier_call_chain(&dummycon_output_nh, 0, NULL);
 }
 
-static int dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
-			  int mode_switch)
+static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
+			   bool mode_switch)
 {
 	/* Redraw, so that we get putc(s) for output done while blanked */
-	return 1;
+	return true;
 }
 #else
 static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y,
 			  unsigned int x) { }
 static void dummycon_putcs(struct vc_data *vc, const u16 *s, unsigned int count,
 			   unsigned int ypos, unsigned int xpos) { }
-static int dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
-			  int mode_switch)
+static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
+			   bool mode_switch)
 {
-	return 0;
+	return false;
 }
 #endif
 

drivers/video/console/mdacon.c

@@ -451,8 +451,8 @@ static bool mdacon_switch(struct vc_data *c)
 	return true;	/* redrawing needed */
 }
 
-static int mdacon_blank(struct vc_data *c, enum vesa_blank_mode blank,
-			int mode_switch)
+static bool mdacon_blank(struct vc_data *c, enum vesa_blank_mode blank,
+			 bool mode_switch)
 {
 	if (mda_type == TYPE_MDA) {
 		if (blank) 
@@ -460,14 +460,14 @@ static int mdacon_blank(struct vc_data *c, enum vesa_blank_mode blank,
 				mda_convert_attr(c->vc_video_erase_char),
 				c->vc_screenbuf_size);
 		/* Tell console.c that it has to restore the screen itself */
-		return 1;
+		return true;
 	} else {
 		if (blank)
 			outb_p(0x00, mda_mode_port);	/* disable video */
 		else
 			outb_p(MDA_MODE_VIDEO_EN | MDA_MODE_BLINK_EN, 
 				mda_mode_port);
-		return 0;
+		return false;
 	}
 }
 

drivers/video/console/newport_con.c

@@ -476,8 +476,8 @@ static bool newport_switch(struct vc_data *vc)
 	return true;
 }
 
-static int newport_blank(struct vc_data *c, enum vesa_blank_mode blank,
-			 int mode_switch)
+static bool newport_blank(struct vc_data *c, enum vesa_blank_mode blank,
+			  bool mode_switch)
 {
 	unsigned short treg;
 
@@ -492,7 +492,8 @@ static int newport_blank(struct vc_data *c, enum vesa_blank_mode blank,
 		newport_vc2_set(npregs, VC2_IREG_CONTROL,
 				(treg & ~(VC2_CTRL_EDISP)));
 	}
-	return 1;
+
+	return true;
 }
 
 static int newport_set_font(int unit, struct console_font *op, unsigned int vpitch)

drivers/video/console/sticon.c

@@ -298,19 +298,20 @@ static bool sticon_switch(struct vc_data *conp)
     return true;	/* needs refreshing */
 }
 
-static int sticon_blank(struct vc_data *c, enum vesa_blank_mode blank,
-			int mode_switch)
+static bool sticon_blank(struct vc_data *c, enum vesa_blank_mode blank,
+			 bool mode_switch)
 {
     if (blank == VESA_NO_BLANKING) {
 	if (mode_switch)
 	    vga_is_gfx = 0;
-	return 1;
+	return true;
     }
     sti_clear(sticon_sti, 0, 0, c->vc_rows, c->vc_cols, BLANK,
 	      font_data[c->vc_num]);
     if (mode_switch)
 	vga_is_gfx = 1;
-    return 1;
+
+    return true;
 }
 
 static u8 sticon_build_attr(struct vc_data *conp, u8 color,

drivers/video/console/vgacon.c

@@ -797,8 +797,8 @@ static void vga_pal_blank(struct vgastate *state)
 	}
 }
 
-static int vgacon_blank(struct vc_data *c, enum vesa_blank_mode blank,
-			int mode_switch)
+static bool vgacon_blank(struct vc_data *c, enum vesa_blank_mode blank,
+			 bool mode_switch)
 {
 	switch (blank) {
 	case VESA_NO_BLANKING:		/* Unblank */

drivers/video/fbdev/core/fbcon.c

@@ -2198,8 +2198,8 @@ static void fbcon_generic_blank(struct vc_data *vc, struct fb_info *info,
 	}
 }
 
-static int fbcon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
-		       int mode_switch)
+static bool fbcon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
+			bool mode_switch)
 {
 	struct fb_info *info = fbcon_info_from_console(vc->vc_num);
 	struct fbcon_ops *ops = info->fbcon_par;
@@ -2238,7 +2238,7 @@ static int fbcon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
 	else
 		fbcon_add_cursor_work(info);
 
-	return 0;
+	return false;
 }
 
 static void fbcon_debug_enter(struct vc_data *vc)

include/linux/console.h

@@ -49,6 +49,9 @@ enum vc_intensity;
  *		Invoked by csi_M and printing to the console.
  * @con_switch: notifier about the console switch; it is supposed to return
  *		true if a redraw is needed.
+ * @con_blank:  blank/unblank the console. The target mode is passed in @blank.
+ *		@mode_switch is set if changing from/to text/graphics. The hook
+ *		is supposed to return true if a redraw is needed.
  * @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)
@@ -70,8 +73,8 @@ struct consw {
 			unsigned int bottom, enum con_scroll dir,
 			unsigned int lines);
 	bool	(*con_switch)(struct vc_data *vc);
-	int	(*con_blank)(struct vc_data *vc, enum vesa_blank_mode blank,
-			     int mode_switch);
+	bool	(*con_blank)(struct vc_data *vc, enum vesa_blank_mode blank,
+			     bool mode_switch);
 	int	(*con_font_set)(struct vc_data *vc, struct console_font *font,
 			unsigned int vpitch, unsigned int flags);
 	int	(*con_font_get)(struct vc_data *vc, struct console_font *font,