From fb79a6da459b20554151eed84c991cd9bd35ff15 Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Mon, 23 Jan 2017 14:20:01 +0200 Subject: [PATCH] usb: xhci: avoid unnecessary calculation No need to calculate remainder and length_field, if there is no data phase of a control transfer. Signed-off-by: Lu Baolu Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-ring.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 61b5fea4cdb3..2374a13efb56 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -3237,7 +3237,7 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags, struct usb_ctrlrequest *setup; struct xhci_generic_trb *start_trb; int start_cycle; - u32 field, length_field, remainder; + u32 field; struct urb_priv *urb_priv; struct xhci_td *td; @@ -3310,16 +3310,16 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags, else field = TRB_TYPE(TRB_DATA); - remainder = xhci_td_remainder(xhci, 0, - urb->transfer_buffer_length, - urb->transfer_buffer_length, - urb, 1); - - length_field = TRB_LEN(urb->transfer_buffer_length) | - TRB_TD_SIZE(remainder) | - TRB_INTR_TARGET(0); - if (urb->transfer_buffer_length > 0) { + u32 length_field, remainder; + + remainder = xhci_td_remainder(xhci, 0, + urb->transfer_buffer_length, + urb->transfer_buffer_length, + urb, 1); + length_field = TRB_LEN(urb->transfer_buffer_length) | + TRB_TD_SIZE(remainder) | + TRB_INTR_TARGET(0); if (setup->bRequestType & USB_DIR_IN) field |= TRB_DIR_IN; queue_trb(xhci, ep_ring, true, -- 2.39.5