msm: 8960: usb: Add msm_bus vote when cable is connected
Drivers need to specify their bandwidth requirements to
bus-scaling driver to get guaranteed bandwidth on fabrics.
USB hardware uses a single buffer to transfer data across the
bus. As a result USB performance is highly dependent on system
fabric frequency as USB controller continuously sends NAKs on
the USB BUS unless complete buffer is filled/drained to the memory.
Hence, request for high bus bandwidth as long as USB cable is
connected to improve USB throughput.
While testing with Class-10 Extreme III SD cards, this patch
seems to improve the IN performance from 15MBps to 24MBps and
OUT performance from 11MBps to 16MBps.
CRs-Fixed: 327557
Change-Id: I21c284c611a09b1b12df9ae7a6f39e0b1bff45ef
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>
3 files changed