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From bfa3dbb343f664573292afb9e44f9abeb81a19de Mon Sep 17 00:00:00 2001
From: Samuel Holland <samuel@sholland.org>
Date: Fri, 25 Oct 2019 17:30:28 +0300
Subject: [PATCH] usb: xhci: fix Immediate Data Transfer endianness
Git-commit: bfa3dbb343f664573292afb9e44f9abeb81a19de
Patch-mainline: v5.4-rc6
References: git-fixes bnc#1151927 5.3.9

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: <stable@vger.kernel.org> # 5.2+
Fixes: 33e39350ebd2 ("usb: xhci: add Immediate Data Transfer support")
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/1572013829-14044-3-git-send-email-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 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;
-- 
2.16.4