On 21-01-14 11:59:07, Daewoong Kim wrote: > DMA mapping of urb->setup_packet is not necessary for xHCI host > controllers. The xHCI specification says that Setup Stage TRB includes > whole Setup Data; therefore, urb->setup_dma will not be used in the xhci > HCD code. > How about bypass map/unmap operation for xHCI control transfer directly? diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 91ab81c3fc79..0a0ab14b7638 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -1374,7 +1374,8 @@ static int xhci_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, xhci = hcd_to_xhci(hcd); - if (xhci_urb_suitable_for_idt(urb)) + if (xhci_urb_suitable_for_idt(urb) || + (usb_endpoint_xfer_control(&urb->ep->desc))) return 0; if (xhci->quirks & XHCI_SG_TRB_CACHE_SIZE_QUIRK) { @@ -1389,6 +1390,9 @@ static void xhci_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb) struct xhci_hcd *xhci; bool unmap_temp_buf = false; + if (usb_endpoint_xfer_control(&urb->ep->desc)) + return; + xhci = hcd_to_xhci(hcd); if (urb->num_sgs && (urb->transfer_flags & URB_DMA_MAP_SINGLE)) > Signed-off-by: Daewoong Kim <daewoong00.kim@xxxxxxx> > --- > drivers/usb/core/hcd.c | 4 +++- > drivers/usb/host/xhci.c | 1 + > include/linux/usb.h | 4 ++++ > 3 files changed, 8 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c > index ad5a0f405a75..b1f9eac93f0d 100644 > --- a/drivers/usb/core/hcd.c > +++ b/drivers/usb/core/hcd.c > @@ -1411,7 +1411,9 @@ int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, > if (usb_endpoint_xfer_control(&urb->ep->desc)) { > if (hcd->self.uses_pio_for_control) > return ret; > - if (hcd->localmem_pool) { > + if (hcd->self.uses_pio_for_setup_pkt) { > + ; /* do nothing */ > + } else if (hcd->localmem_pool) { > ret = hcd_alloc_coherent( > urb->dev->bus, mem_flags, > &urb->setup_dma, > diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c > index e86940571b4c..c263aee82dc0 100644 > --- a/drivers/usb/host/xhci.c > +++ b/drivers/usb/host/xhci.c > @@ -643,6 +643,7 @@ int xhci_run(struct usb_hcd *hcd) > */ > > hcd->uses_new_polling = 1; > + hcd->self.uses_pio_for_setup_pkt = 1; > if (!usb_hcd_is_primary_hcd(hcd)) > return xhci_run_finished(xhci); > > diff --git a/include/linux/usb.h b/include/linux/usb.h > index 7d72c4e0713c..76600e8de414 100644 > --- a/include/linux/usb.h > +++ b/include/linux/usb.h > @@ -430,6 +430,10 @@ struct usb_bus { > * Does the host controller use PIO > * for control transfers? > */ > + u8 uses_pio_for_setup_pkt; /* > + * Does the host controller use PIO > + * for setup packets? > + */ > u8 otg_port; /* 0, or number of OTG/HNP port */ > unsigned is_b_host:1; /* true during some HNP roleswitches */ > unsigned b_hnp_enable:1; /* OTG: did A-Host enable HNP? */ > -- > 2.17.1 > -- Thanks, Peter Chen