The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From d53dc38857f6dbefabd9eecfcbf67b6eac9a1ef4 Mon Sep 17 00:00:00 2001
From: Minas Harutyunyan <Minas.Harutyunyan@xxxxxxxxxxxx>
Date: Tue, 20 Jul 2021 05:41:24 -0700
Subject: [PATCH] usb: dwc2: gadget: Fix sending zero length packet in DDMA
mode.
Sending zero length packet in DDMA mode perform by DMA descriptor
by setting SP (short packet) flag.
For DDMA in function dwc2_hsotg_complete_in() does not need to send
zlp.
Tested by USBCV MSC tests.
Fixes: f71b5e2533de ("usb: dwc2: gadget: fix zero length packet transfers")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Minas Harutyunyan <Minas.Harutyunyan@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/967bad78c55dd2db1c19714eee3d0a17cf99d74a.1626777738.git.Minas.Harutyunyan@xxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 74d25019272f..3146df6e6510 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -2749,12 +2749,14 @@ static void dwc2_hsotg_complete_in(struct dwc2_hsotg *hsotg,
return;
}
- /* Zlp for all endpoints, for ep0 only in DATA IN stage */
+ /* Zlp for all endpoints in non DDMA, for ep0 only in DATA IN stage */
if (hs_ep->send_zlp) {
- dwc2_hsotg_program_zlp(hsotg, hs_ep);
hs_ep->send_zlp = 0;
- /* transfer will be completed on next complete interrupt */
- return;
+ if (!using_desc_dma(hsotg)) {
+ dwc2_hsotg_program_zlp(hsotg, hs_ep);
+ /* transfer will be completed on next complete interrupt */
+ return;
+ }
}
if (hs_ep->index == 0 && hsotg->ep0_state == DWC2_EP0_DATA_IN) {
