> - val = simple_strtoul(buf, &endp, 0);> - if (endp == buf || val > 0x3f)> - return -EINVAL;> + ret = kstrtoul(buf, 0, &val);> + if (ret)> + return ret;> val = (val << 12) | (sysreg_read(PCCR) & 0xfffc0fff);you removed 0x3f checkthis conversion is not trivial as it seems