aty: use memory_read_from_buffer()

Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/video/aty/radeon_base.c

@@ -2098,15 +2098,7 @@ static void radeon_identify_vram(struct radeonfb_info *rinfo)
 
 static ssize_t radeon_show_one_edid(char *buf, loff_t off, size_t count, const u8 *edid)
 {
-	if (off > EDID_LENGTH)
-		return 0;
-
-	if (off + count > EDID_LENGTH)
-		count = EDID_LENGTH - off;
-
-	memcpy(buf, edid + off, count);
-
-	return count;
+	return memory_read_from_buffer(buf, count, &off, edid, EDID_LENGTH);
 }