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.
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
