The arguments to queue_trb are always byteswapped to LE for placement in
the ring, but this should not happen in the case of immediate data; the
bytes copied out of transfer_buffer are already in the correct order.
Add a complementary byteswap so the bytes end up in the ring correctly.

This was observed on BE ppc64 with a "Texas Instruments TUSB73x0
SuperSpeed USB 3.0 xHCI Host Controller [104c:8241]" as a ch341
usb-serial adapter ("1a86:7523 QinHeng Electronics HL-340 USB-Serial
adapter") always transmitting the same character (generally NUL) over
the serial link regardless of the key pressed.

Cc: sta...@vger.kernel.org
Fixes: 33e39350ebd2 ("usb: xhci: add Immediate Data Transfer support")
Signed-off-by: Samuel Holland <sam...@sholland.org>
---
 drivers/usb/host/xhci-ring.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 85ceb43e3405..e7aab31fd9a5 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -3330,6 +3330,7 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t 
mem_flags,
                        if (xhci_urb_suitable_for_idt(urb)) {
                                memcpy(&send_addr, urb->transfer_buffer,
                                       trb_buff_len);
+                               le64_to_cpus(&send_addr);
                                field |= TRB_IDT;
                        }
                }
@@ -3475,6 +3476,7 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t 
mem_flags,
                if (xhci_urb_suitable_for_idt(urb)) {
                        memcpy(&addr, urb->transfer_buffer,
                               urb->transfer_buffer_length);
+                       le64_to_cpus(&addr);
                        field |= TRB_IDT;
                } else {
                        addr = (u64) urb->transfer_dma;
-- 
2.21.0

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