[PATCH] s390: improve response code handling in chsc_enable_facility()

Rather than checking for some known failures, check positively for the
success response code 0x0001 and return -EIO for unrecognized failure
response codes.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Greg Smith <gsmith@nc.rr.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/s390/cio/chsc.c

@@ -1115,6 +1115,9 @@ chsc_enable_facility(int operation_code)
 		goto out;
 	}
 	switch (sda_area->response.code) {
+	case 0x0001: /* everything ok */
+		ret = 0;
+		break;
 	case 0x0003: /* invalid request block */
 	case 0x0007:
 		ret = -EINVAL;
@@ -1123,6 +1126,8 @@ chsc_enable_facility(int operation_code)
 	case 0x0101: /* facility not provided */
 		ret = -EOPNOTSUPP;
 		break;
+	default: /* something went wrong */
+		ret = -EIO;
 	}
  out:
 	free_page((unsigned long)sda_area);