lkml.org 
[lkml]   [2016]   [Apr]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3.12 65/78] mmc: Allow forward compatibility for eMMC
Date
From: Romain Izard <romain.izard.pro@gmail.com>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 03a59437ef6b6ad7fb0165cb9b96c08d6bf057fc upstream.

As stated by the eMMC 5.0 specification, a chip should not be rejected
only because of the revision stated in the EXT_CSD_REV field of the
EXT_CSD register.

Remove the control on this value, the control of the CSD_STRUCTURE field
should be sufficient to reject future incompatible changes.

Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
drivers/mmc/core/mmc.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 6d02012a1d0b..36d6701de972 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -292,13 +292,12 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
}
}

+ /*
+ * The EXT_CSD format is meant to be forward compatible. As long
+ * as CSD_STRUCTURE does not change, all values for EXT_CSD_REV
+ * are authorized, see JEDEC JESD84-B50 section B.8.
+ */
card->ext_csd.rev = ext_csd[EXT_CSD_REV];
- if (card->ext_csd.rev > 7) {
- pr_err("%s: unrecognised EXT_CSD revision %d\n",
- mmc_hostname(card->host), card->ext_csd.rev);
- err = -EINVAL;
- goto out;
- }

card->ext_csd.raw_sectors[0] = ext_csd[EXT_CSD_SEC_CNT + 0];
card->ext_csd.raw_sectors[1] = ext_csd[EXT_CSD_SEC_CNT + 1];
--
2.8.1
\
 
 \ /
  Last update: 2016-04-22 13:21    [W:0.196 / U:0.748 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site