Input: keyboard - simplify emulate_raw() implementation

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/char/keyboard.c

@@ -1025,7 +1025,7 @@ static const unsigned short x86_keycodes[256] =
 	 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
 	 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
 	 80, 81, 82, 83, 84,118, 86, 87, 88,115,120,119,121,112,123, 92,
-	284,285,309,298,312, 91,327,328,329,331,333,335,336,337,338,339,
+	284,285,309,  0,312, 91,327,328,329,331,333,335,336,337,338,339,
 	367,288,302,304,350, 89,334,326,267,126,268,269,125,347,348,349,
 	360,261,262,263,268,376,100,101,321,316,373,286,289,102,351,355,
 	103,104,105,275,287,279,306,106,274,107,294,364,358,363,362,361,
@@ -1047,38 +1047,55 @@ extern void sun_do_break(void);
 static int emulate_raw(struct vc_data *vc, unsigned int keycode,
 		       unsigned char up_flag)
 {
-	if (keycode > 255 || !x86_keycodes[keycode])
-		return -1;
+	int code;
 
 	switch (keycode) {
 		case KEY_PAUSE:
 			put_queue(vc, 0xe1);
 			put_queue(vc, 0x1d | up_flag);
 			put_queue(vc, 0x45 | up_flag);
-			return 0;
+			break;
+
 		case KEY_HANGEUL:
 			if (!up_flag)
 				put_queue(vc, 0xf2);
-			return 0;
+			break;
+
 		case KEY_HANJA:
 			if (!up_flag)
 				put_queue(vc, 0xf1);
-			return 0;
-	}
+			break;
 
-	if (keycode == KEY_SYSRQ && sysrq_alt) {
-		put_queue(vc, 0x54 | up_flag);
-		return 0;
-	}
+		case KEY_SYSRQ:
+			/*
+			 * Real AT keyboards (that's what we're trying
+			 * to emulate here emit 0xe0 0x2a 0xe0 0x37 when
+			 * pressing PrtSc/SysRq alone, but simply 0x54
+			 * when pressing Alt+PrtSc/SysRq.
+			 */
+			if (sysrq_alt) {
+				put_queue(vc, 0x54 | up_flag);
+			} else {
+				put_queue(vc, 0xe0);
+				put_queue(vc, 0x2a | up_flag);
+				put_queue(vc, 0xe0);
+				put_queue(vc, 0x37 | up_flag);
+			}
+			break;
+
+		default:
+			if (keycode > 255)
+				return -1;
 
-	if (x86_keycodes[keycode] & 0x100)
-		put_queue(vc, 0xe0);
+			code = x86_keycodes[keycode];
+			if (!code)
+				return -1;
 
-	put_queue(vc, (x86_keycodes[keycode] & 0x7f) | up_flag);
+			if (code & 0x100)
+				put_queue(vc, 0xe0);
+			put_queue(vc, (code & 0x7f) | up_flag);
 
-	if (keycode == KEY_SYSRQ) {
-		put_queue(vc, 0xe0);
-		put_queue(vc, 0x37 | up_flag);
+			break;
 	}
 
 	return 0;