[PATCH 4.17 057/324] dwc2: gadget: Fix ISOC IN DDMA PID bitfield value calculation

[Greg Kroah-Hartman]

4.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Minas Harutyunyan <Minas.Harutyunyan@xxxxxxxxxxxx>

[ Upstream commit 1d8e5c00275825fc42aaa5597dab1d0b5b26bb64 ]

PID bitfield in descriptor should be set based on particular request
length, not based on EP's mc value. PID value can't be set to 0 even
request length is 0.

Signed-off-by: Minas Harutyunyan <hminas@xxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/usb/dwc2/gadget.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -808,6 +808,7 @@ static int dwc2_gadget_fill_isoc_desc(st
 	u32 index;
 	u32 maxsize = 0;
 	u32 mask = 0;
+	u8 pid = 0;
 
 	maxsize = dwc2_gadget_get_desc_params(hs_ep, &mask);
 	if (len > maxsize) {
@@ -853,7 +854,11 @@ static int dwc2_gadget_fill_isoc_desc(st
 			 ((len << DEV_DMA_NBYTES_SHIFT) & mask));
 
 	if (hs_ep->dir_in) {
-		desc->status |= ((hs_ep->mc << DEV_DMA_ISOC_PID_SHIFT) &
+		if (len)
+			pid = DIV_ROUND_UP(len, hs_ep->ep.maxpacket);
+		else
+			pid = 1;
+		desc->status |= ((pid << DEV_DMA_ISOC_PID_SHIFT) &
 				 DEV_DMA_ISOC_PID_MASK) |
 				((len % hs_ep->ep.maxpacket) ?
 				 DEV_DMA_SHORT : 0) |