usb: gadget: udc: renesas_usb3: Fix b-device mode for "workaround"

commit afc92514a34c7414b28047b1205a6b709103c699 upstream.

If the "workaround_for_vbus" is true, the driver will not call
usb_disconnect(). So, since the controller keeps some registers'
value, the driver doesn't re-enumarate suitable speed after
the b-device mode is disabled. To fix the issue, this patch
adds usb_disconnect() calling in renesas_usb3_b_device_write()
if workaround_for_vbus is true.

Fixes: 43ba968b00ea ("usb: gadget: udc: renesas_usb3: add debugfs to set the b-device mode")
Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/udc/renesas_usb3.c b/drivers/usb/gadget/udc/renesas_usb3.c
index 36a706f..ade0723 100644 (file)
--- a/drivers/usb/gadget/udc/renesas_usb3.c
+++ b/drivers/usb/gadget/udc/renesas_usb3.c
@@ -2374,6 +2374,9 @@ static ssize_t renesas_usb3_b_device_write(struct file *file,
        else
                usb3->forced_b_device = false;
 
+       if (usb3->workaround_for_vbus)
+               usb3_disconnect(usb3);
+
        /* Let this driver call usb3_connect() anyway */
        usb3_check_id(usb3);