[PATCH 5.10 070/545] usb: dwc3: gadget: fix high speed multiplier setting

From: Greg Kroah-Hartman
Date: Fri Aug 19 2022 - 11:53:31 EST


From: Michael Grzeschik <m.grzeschik@xxxxxxxxxxxxxx>

commit 8affe37c525d800a2628c4ecfaed13b77dc5634a upstream.

For High-Speed Transfers the prepare_one_trb function is calculating the
multiplier setting for the trb based on the length parameter of the trb
currently prepared. This assumption is wrong. For trbs with a sg list,
the length of the actual request has to be taken instead.

Fixes: 40d829fb2ec6 ("usb: dwc3: gadget: Correct ISOC DATA PIDs for short packets")
Cc: stable <stable@xxxxxxxxxx>
Signed-off-by: Michael Grzeschik <m.grzeschik@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220704141812.1532306-3-m.grzeschik@xxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/dwc3/gadget.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1052,10 +1052,10 @@ static void dwc3_prepare_one_trb(struct
unsigned int mult = 2;
unsigned int maxp = usb_endpoint_maxp(ep->desc);

- if (trb_length <= (2 * maxp))
+ if (req->request.length <= (2 * maxp))
mult--;

- if (trb_length <= maxp)
+ if (req->request.length <= maxp)
mult--;

trb->size |= DWC3_TRB_SIZE_PCM1(mult);