[PATCH] usb: kbd: dwc2: Increase wait for dwc2 controller reset by 125us

Filip Zaludek filip.zaludek at oracle.com
Mon May 15 16:53:25 CEST 2023

Two following performance patches applied together occasionally harm usb keyboard on RPi3.

'dwc2: use the nonblock argument in submit_int_msg'
commit 9dcab2c4d2cb50ab1864c818b82a72393c160236

'console: usb: kbd: Limit poll frequency to improve performance'
commit 96991e652f541323a03c5b7e075d54a117091618

This empirically increased by sub-millisecond wait for dwc2 controller reset makes
keyboard reliable.

Signed-off-by: Filip Zaludek <filip.zaludek at oracle.com>
 drivers/usb/host/dwc2.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c
index 23060fc369..71b66a52ed 100644
--- a/drivers/usb/host/dwc2.c
+++ b/drivers/usb/host/dwc2.c
@@ -764,7 +764,7 @@ static int dwc_otg_submit_rh_msg_out(struct dwc2_priv *priv,
-			mdelay(50);
+			udelay(50125);
 			clrbits_le32(&regs->hprt0, DWC2_HPRT0_PRTRST);

More information about the U-Boot mailing list