On Thu, 2018-01-18 at 22:19 +0800, weiping zhang wrote: > - return sprintf(buf, "%s\n", sd_cache_types[ct]); > + return sprintf(buf, "%s\n%s\nwrite:%s, read:%s\n", > sd_cache_types[ct], > + sd_wce_rcd[ct], sdkp->WCE ? "on" : "off", > + sdkp->RCD ? "off" : "on"); I don't think we can do this. The output of the cache type in sysfs is a user exported ABI. We'd potentially break it if we add extra stuff. James