@@ -2083,9 +2083,19 @@ static void dwc3_gadget_config_params(struct usb_gadget *g,
/* Recommended BESL */
if (!dwc->dis_enblslpm_quirk) {
- params->besl_baseline = 0;
+ /*
+ * If the recommended BESL baseline is 0 or if the BESL deep is
+ * less than 2, Microsoft's Windows 10 host usb stack will issue
+ * a usb reset immediately after it receives the extended BOS
+ * descriptor and the enumeration will fail. To maintain
+ * compatibility with the Windows' usb stack, let's set the
+ * recommended BESL baseline to 1 and clamp the BESL deep to be
+ * within 2 to 15.
+ */
+ params->besl_baseline = 1;
if (dwc->is_utmi_l1_suspend)
- params->besl_deep = min_t(u8, dwc->hird_threshold, 15);
+ params->besl_deep =
+ clamp_t(u8, dwc->hird_threshold, 2, 15);
}
/* U1 Device exit Latency */
While testing our host system using Microsoft's usb stack against our gadget for various BESL values, we found an issue with their usb stack when the recommended baseline BESL value is 0 (125us) or when the deep BESL is 1 or less. The Windows host will issue a usb reset immediately after it receives the extended BOS descriptor and the enumeration will fail after a few attempts. To keep compatibility with Microsoft's host usb stack, let's workaround this issue by using the recommended baseline BESL of 1 (or 150us) and clamp the deep BESL value within 2 to 15. This was tested against Windows 10 build 18956. Signed-off-by: Thinh Nguyen <thinhn@synopsys.com> --- changes in v2: - Add comment in code for the new change drivers/usb/dwc3/gadget.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)