From: Douglas Anderson dianders@chromium.org
commit ba2d139b02ba684c6c101de42fed782d6cd2b997 upstream.
In commit 46d179525a1f ("mmc: dw_mmc: Wait for data transfer after response errors.") we fixed a tuning-induced hang that I saw when stress testing tuning on certain SD cards. I won't re-hash that whole commit, but the summary is that as a normal part of tuning you need to deal with transfer errors and there were cases where these transfer errors was putting my system into a bad state causing all future transfers to fail. That commit fixed handling of the transfer errors for me.
In downstream Chrome OS my fix landed and had the same behavior for all SD/MMC commands. However, it looks like when the commit landed upstream we limited it to only SD tuning commands. Presumably this was to try to get around problems that Alim Akhtar reported on exynos [1].
Unfortunately while stress testing reboots (and suspend/resume) on some rk3288-based Chromebooks I found the same problem on the eMMC on some of my Chromebooks (the ones with Hynix eMMC). Since the eMMC tuning command is different (MMC_SEND_TUNING_BLOCK_HS200 vs. MMC_SEND_TUNING_BLOCK) we were basically getting back into the same situation.
I'm hoping that whatever problems exynos was having in the past are somehow magically fixed now and we can make the behavior the same for all commands.
[1] https://lkml.kernel.org/r/CAGOxZ53WfNbaMe0_AM0qBqU47kAfgmPBVZC8K8Y-_J3mDMqW4...
Fixes: 46d179525a1f ("mmc: dw_mmc: Wait for data transfer after response errors.") Signed-off-by: Douglas Anderson dianders@chromium.org Cc: Marek Szyprowski m.szyprowski@samsung.com Cc: Alim Akhtar alim.akhtar@gmail.com Cc: Enric Balletbo i Serra enric.balletbo@collabora.com Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/mmc/host/dw_mmc.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
--- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -2038,8 +2038,7 @@ static void dw_mci_tasklet_func(unsigned * delayed. Allowing the transfer to take place * avoids races and keeps things simple. */ - if ((err != -ETIMEDOUT) && - (cmd->opcode == MMC_SEND_TUNING_BLOCK)) { + if (err != -ETIMEDOUT) { state = STATE_SENDING_DATA; continue; }