• Andreas Koop's avatar
    mmc: mmc_spi: Enable stable writes · 3a6ffb3c
    Andreas Koop authored
    While using the mmc_spi driver occasionally errors like this popped up:
    mmcblk0: error -84 transferring data end_request: I/O error, dev mmcblk0, sector 581756
    I looked on the Internet for occurrences of the same problem and came
    across a helpful post [1]. It includes source code to reproduce the bug.
    There is also an analysis about the cause. During transmission data in the
    supplied buffer is being modified. Thus the previously calculated checksum
    is not correct anymore.
    After some digging I found out that device drivers are supposed to report
    they need stable writes. To fix this I set the appropriate flag at queue
    initialization if CRC checksumming is enabled for that SPI host.
    https://groups.google.com/forum/#!msg/sim1/gLlzWeXGFr8/KevXinUXfc8JSigned-off-by: default avatarAndreas Koop <andreas.koop@zf.com>
    [shihpo: Rebase on top of v5.3-rc1]
    Signed-off-by: default avatarShihPo Hung <shihpo.hung@sifive.com>
    Cc: Paul Walmsley <paul.walmsley@sifive.com>
    CC: stable@vger.kernel.org
    Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
queue.c 11.8 KB