static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
 {
        struct mtd_info *mtd = mfi->mtd;
+       size_t retlen;
        int ret = 0;
 
+       /*
+        * Make a fake call to mtd_read_fact_prot_reg() to check if OTP
+        * operations are supported.
+        */
+       if (mtd_read_fact_prot_reg(mtd, -1, -1, &retlen, NULL) == -EOPNOTSUPP)
+               return -EOPNOTSUPP;
+
        switch (mode) {
        case MTD_OTP_FACTORY:
-               if (!mtd->read_fact_prot_reg)
-                       ret = -EOPNOTSUPP;
-               else
-                       mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
+               mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
                break;
        case MTD_OTP_USER:
-               if (!mtd->read_fact_prot_reg)
-                       ret = -EOPNOTSUPP;
-               else
-                       mfi->mode = MTD_FILE_MODE_OTP_USER;
+               mfi->mode = MTD_FILE_MODE_OTP_USER;
                break;
        default:
                ret = -EINVAL;
 
                                         u_char *buf)
 {
        *retlen = 0;
+       if (!mtd->read_fact_prot_reg)
+               return -EOPNOTSUPP;
        return mtd->read_fact_prot_reg(mtd, from, len, retlen, buf);
 }
 
                                         u_char *buf)
 {
        *retlen = 0;
+       if (!mtd->read_user_prot_reg)
+               return -EOPNOTSUPP;
        return mtd->read_user_prot_reg(mtd, from, len, retlen, buf);
 }