mmc: tegra: Disable UHS-I modes for Tegra124
authorJon Hunter <jonathanh@nvidia.com>
Wed, 13 Apr 2016 14:35:56 +0000 (15:35 +0100)
committerUlf Hansson <ulf.hansson@linaro.org>
Thu, 14 Apr 2016 09:40:01 +0000 (11:40 +0200)
commit70ad7f7e40af31e7ab4a1719602542856b7ea856
treea38fc705bee69c64a315071f3b61a9cd7b8e5087
parent9aaf3437aa72ed5370bf32c99580a3fa2c330e3d
mmc: tegra: Disable UHS-I modes for Tegra124

Tegra124 has been randomly hanging during system suspend when entering
the Tegra LP1 low power state. The hang is caused by the Tegra SDHCI
driver and linked to the UHS-I tuning sequence. Disabling the UHS-I
modes for Tegra124 prevents any hangs from occurring when entering
system suspend.

Unfortunately, the tuning sequence described in the public Tegra
documentation is incomplete and on inspection of the current tuning
sequence that has been implemented is also incomplete and may cause
problems. In the short-term it is safer to disable UHS-I modes for now
and fix later because it would be too large of a change to simply patch
now. Therefore, disable UHS-I modes for Tegra124.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
drivers/mmc/host/sdhci-tegra.c