servod: explicitly claim interface USB interface.

From the second run of servod, dut-control i2c IO gets timeout
in _raw_wr_rd() temporarily at the beginning, and it takes a
few attempts to get back normal. The endpoint resource seems
not released.

This CL detaches the active stm32usb driver and claim it before
it sets configuration.

CQ-DEPEND=CL:1250029, CL:1522846
BUG=b:126189871
BRANCH=none
TEST=manually ran dut-control on bip and ampton.

[Before this CL]
$ dut-control dut_i2c_mux
Problem with ['dut_i2c_mux'] :: [Errno 110] Operation timed out
$ dut-control dut_i2c_mux
Problem with ['dut_i2c_mux'] :: [Errno 110] Operation timed out
$ dut-control dut_i2c_mux
dut_i2c_mux:none
$ dut-control dut_i2c_mux
dut_i2c_mux:none

[After this CL]
$ dut-control dut_i2c_mux
dut_i2c_mux:none
$ dut-control dut_i2c_mux
dut_i2c_mux:none
$ dut-control dut_i2c_mux
dut_i2c_mux:none
$ dut-control dut_i2c_mux
dut_i2c_mux:none

Change-Id: I20bd53c361d8298372901c9c5670d3f1e2c2a3ab
Signed-off-by: Namyoon Woo <namyoon@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1490412
Commit-Ready: Nick Sanders <nsanders@chromium.org>
Reviewed-by: Nick Sanders <nsanders@chromium.org>
Reviewed-by: Matthew Blecker <matthewb@chromium.org>
1 file changed