From mboxrd@z Thu Jan 1 00:00:00 1970 From: Romain Izard Subject: [PATCH] mmc: core: production year for eMMC 4.41 and later Date: Fri, 14 Jun 2013 14:25:44 +0200 Message-ID: <1371212744-31596-1-git-send-email-romain.izard.pro@gmail.com> Return-path: Received: from mail-wg0-f41.google.com ([74.125.82.41]:59902 "EHLO mail-wg0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752569Ab3FNM0F (ORCPT ); Fri, 14 Jun 2013 08:26:05 -0400 Received: by mail-wg0-f41.google.com with SMTP id y10so1126337wgg.2 for ; Fri, 14 Jun 2013 05:26:03 -0700 (PDT) Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Chris Ball Cc: linux-mmc@vger.kernel.org, Romain Izard 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 --- drivers/mmc/core/mmc.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 3a69b94..3914523 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -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; -- 1.8.1.2