usb: gadget: udc: renesas_usb3: add a safety connection way for forced_b_device
[ Upstream commit ceb94bc52c437463f0903e61060a94a2226fb672 ] This patch adds a safety connection way for "forced_b_device" with "workaround_for_vbus" like below: < Example for R-Car E3 Ebisu > # modprobe <any usb gadget driver> # echo 1 > /sys/kernel/debug/ee020000.usb/b_device (connect a usb cable to host side.) # echo 2 > /sys/kernel/debug/ee020000.usb/b_device Previous code should have connected a usb cable before the "b_device" is set to 1 on the Ebisu board. However, if xHCI driver on the board is probed, it causes some troubles: - Conflicts USB VBUS/signals between the board and another host. - "Cannot enable. Maybe the USB cable is bad?" might happen on both the board and another host with a usb hub. - Cannot enumerate a usb gadget correctly because an interruption of VBUS change happens unexpectedly. Reported-by: NKazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com> Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: NFelipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: NSasha Levin <sashal@kernel.org>
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