mmc: core: Set read only for SD cards with permanent write protect bit

commit 917a5336f2c27928be270226ab374ed0cbf3805d upstream.

Some of SD cards sets permanent write protection bit in their CSD register,
due to lifespan or internal problem. To avoid unnecessary I/O write
operations, let's parse the bits in the CSD during initialization and mark
the card as read only for this case.

Signed-off-by: Seunghui Lee <sh043.lee@samsung.com>
Link: https://lore.kernel.org/r/20210222083156.19158-1-sh043.lee@samsung.com
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Seunghui Lee 2021-02-22 17:31:56 +09:00 committed by Greg Kroah-Hartman
parent 42998c98ce
commit c80524b9e4
1 changed files with 6 additions and 0 deletions

View File

@ -135,6 +135,9 @@ static int mmc_decode_csd(struct mmc_card *card)
csd->erase_size = UNSTUFF_BITS(resp, 39, 7) + 1;
csd->erase_size <<= csd->write_blkbits - 9;
}
if (UNSTUFF_BITS(resp, 13, 1))
mmc_card_set_readonly(card);
break;
case 1:
/*
@ -169,6 +172,9 @@ static int mmc_decode_csd(struct mmc_card *card)
csd->write_blkbits = 9;
csd->write_partial = 0;
csd->erase_size = 1;
if (UNSTUFF_BITS(resp, 13, 1))
mmc_card_set_readonly(card);
break;
default:
pr_err("%s: unrecognised CSD structure version %d\n",