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Subject[PATCH] usb: core: Check portchange C_PORT_RESET after resetting
Based on USB2.0 Spec Section

"This bit is set when the port transitions from the Resetting state (or,
if present, the Speed_eval state) to the Enabled state."

Also Section

"Setting the reset feature PORT_RESET causes the hub to signal reset on
that port. When the reset signaling is complete, the hub sets the
C_PORT_RESET status change and immediately enables the port."

So let's also check C_PORT_RESET for reset completion.

Signed-off-by: Kai-Heng Feng <>
drivers/usb/core/hub.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 7801bb30bdba..d96058372280 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2721,7 +2721,8 @@ static int hub_port_wait_reset(struct usb_hub *hub, int port1,
* so also wait for the connection to be re-established.
if (!(portstatus & USB_PORT_STAT_RESET) &&
- (portstatus & USB_PORT_STAT_CONNECTION))
+ (portstatus & USB_PORT_STAT_CONNECTION) &&
+ (portchange & USB_PORT_STAT_C_RESET))

/* switch to the long delay after two short delay failures */
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