tree 80c4c186f1765fb057c26bca5a59a98d96e2e109
parent 6840a345224653883db887c3cbed0e36483686cf
author Bin Meng <bmeng.cn@gmail.com> 1504789998 -0700
committer Marek Vasut <marek.vasut+renesas@gmail.com> 1506507142 +0200

dm: usb: xhci: Implement get_max_xfer_size() operation

xHCD allocates one segment which includes 64 TRBs for each endpoint
and the last TRB in this segment is configured as a link TRB to form
a TRB ring. Each TRB can transfer up to 64K bytes, however data
buffers referenced by transfer TRBs shall not span 64KB boundaries.
Hence the maximum number of TRBs we can use in one transfer is 62.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>