Commit 7c4f10ac authored Jun 14, 2013 by Romain Izard Committed by Chris Ball Jul 05, 2013

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>

parent d7a985e0

drivers/mmc/core/mmc.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -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;