Hi Per >>>>>> >>>>>> if (card->ext_csd.rev >= 5) { >>>>>> + /* check whether the eMMC card support BKOPS */ >>>>>> + if (ext_csd[EXT_CSD_BKOPS_SUPPORT] & 0x1) { >>>>>> + card->ext_csd.bkops = 1; >>>>>> + card->ext_csd.bkops_en = 1; >>>>> What if the card has not enabled bkops? This bit could be unset. >>>>> card->ext_csd.bkops_en = ext_csd[EXT_CSD_BKOPS_EN]; >>>> When card is supported the bkops, bkops_en bit is set by default... >>>> >>> How do you know if the bkops_en is really enabled in th ext_csd? >>> It could be unset in the ext_csd, right? >> >> In emmc4.5 spec, if card is supported the bkops, bkops_en is set by default. > If bkops_en is set by default it should be in the the ext_csd too, right? > It should be safer to trust the value of ext_csd[EXT_CSD_BKOPS_EN] in > this case I think. If we want to ensure whether bkops_en bit is set or not, your approach is right. Best Regards, Jaehoon Chung -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html