• Roger Tseng's avatar
    mmc: rtsx_usb_sdmmc: fix incorrect last byte in R2 response · 6f67cc6f
    Roger Tseng authored
    Current code erroneously fill the last byte of R2 response with an undefined
    value. In addition, the controller actually 'offloads' the last byte
    (CRC7, end bit) while receiving R2 response and thus it's impossible to get the
    actual value. This could cause mmc stack to obtain inconsistent CID from the
    same card after resume and misidentify it as a different card.
    
    Fix by assigning dummy CRC and end bit: {7'b0, 1} = 0x1 to the last byte of R2.
    
    Cc: <stable@vger.kernel.org> # v3.16+
    Fixes: c7f6558d ("mmc: Add realtek USB sdmmc host driver")
    Signed-off-by: default avatarRoger Tseng <rogerable@realtek.com>
    Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
    6f67cc6f
rtsx_usb_sdmmc.c 35.9 KB