USB: EHCI: create per-TT bandwidth tables
This patch continues the scheduling changes in ehci-hcd by adding a table to store the bandwidth allocation below each TT. This will speed up the scheduling code, as it will no longer need to read through the entire schedule to compute the bandwidth currently in use. Properly speaking, the FS/LS budget calculations should be done in terms of full-speed bytes per microframe, as described in the USB-2 spec. However the driver currently uses microseconds per microframe, and the scheduling code isn't robust enough at this point to change over. For the time being, we leave the calculations as they are. Signed-off-by: NAlan Stern <stern@rowland.harvard.edu> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
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