r8152: Increase USB control msg timeout to 5000ms as per spec
[ Upstream commit a5feba71 ] According to the comment next to USB_CTRL_GET_TIMEOUT and USB_CTRL_SET_TIMEOUT, although sending/receiving control messages is usually quite fast, the spec allows them to take up to 5 seconds. Let's increase the timeout in the Realtek driver from 500ms to 5000ms (using the #defines) to account for this. This is not just a theoretical change. The need for the longer timeout was seen in testing. Specifically, if you drop a sc7180-trogdor based Chromebook into the kdb debugger and then "go" again after sitting in the debugger for a while, the next USB control message takes a long time. Out of ~40 tests the slowest USB control message was 4.5 seconds. While dropping into kdb is not exactly an end-user scenario, the above is similar to what could happen due to an temporary interrupt storm, what could happen if there was a host controller (HW or SW) issue, or what could happen if the Realtek device got into a confused state and needed time to recover. This change is fairly critical since the r8152 driver in Linux doesn't expect register reads/writes (which are backed by USB control messages) to fail. Fixes: ac718b69 ("net/usb: new driver for RTL8152") Suggested-by:Hayes Wang <hayeswang@realtek.com> Signed-off-by:
Douglas Anderson <dianders@chromium.org> Reviewed-by:
Grant Grundler <grundler@chromium.org> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
Sasha Levin <sashal@kernel.org>
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