[PATCH] ENOTTY for rtc ioctl

Paul Gortmaker <p_gortmaker@yahoo.com>: ENOTTY for rtc ioctl:
   ioctl(d, valid, crap) --> -EINVAL
   ioctl(d, crap, ....)  --> -ENOTTY

  man ioctl agrees:

         ENOTTY The specified request does not apply to the kind of
                object that the descriptor d references.

  Currently we return -EINVAL for both cases which is not as
  informative for debugging stuff.

  Patch is for 2.5.6 but applies cleanly (with minor offset) to 2.4.19p2

  Paul.

(Included in 2.2)
(Included in 2.4)

drivers/char/rtc.c

@@ -544,7 +544,7 @@ static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, int kernel)
 		return 0;
 	}
 	default:
-		return -EINVAL;
+		return -ENOTTY;
 	}
 	return copy_to_user((void *)arg, &wtime, sizeof wtime) ? -EFAULT : 0;
 }