tree 6b3c34b585d7412cf1c82d0eb33b389ea0fa8e0f
parent 6f60c22252af05df94352240f30f9fc84090d88d
author Mikko Vinni <mmvinni@yahoo.com> 1302615378 -0400
committer Chris Ball <cjb@laptop.org> 1306285289 -0400

mmc: sdhci: work around broken dma boundary behavior

Some SD host controllers (noticed on an integrated JMicron SD reader on an
HP Pavilion dv5-1250eo laptop) don't update the dma address register before
signaling a dma interrupt due to a dma boundary. Update the register
manually to the next boundary (by default 512KiB), at which the transfer
stopped.

As long as each transfer is at most 512KiB in size (guaranteed by a BUG_ON
in sdhci_prepare_data()) and the boundary is kept at the default value,
this fix is needed at most once per transfer. Smaller boundaries are taken
care of by counting the transferred bytes.

Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=28462

Signed-off-by: Mikko Vinni <mmvinni@yahoo.com>
Signed-off-by: Chris Ball <cjb@laptop.org>