mmc: core: production year for eMMC 4.41 and later

The field containing the production date in the CID register only uses
4 bits to encode the year, starting from 1997 in the original standard.
In 2013, the production year field contains 0, and the kernel reports a
1997 production date.

The eMMC 4.51 specification adds a new interpretation rule. For all
devices implementing the 4.41 specification or later, the production
year field will be interpreted as a value between 2010 and 2025, with
0 corresponding to 2013.

Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Romain Izard 2013-06-14 14:25:44 +02:00 committed by Chris Ball
parent d7a985e08f
commit 7c4f10ac5a

View file

@ -482,6 +482,10 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
}
if (card->ext_csd.rev >= 5) {
/* Adjust production date as per JEDEC JESD84-B451 */
if (card->cid.year < 2010)
card->cid.year += 16;
/* check whether the eMMC card supports BKOPS */
if (ext_csd[EXT_CSD_BKOPS_SUPPORT] & 0x1) {
card->ext_csd.bkops = 1;