dwc2: gadget: Fix ISOC IN DDMA PID bitfield value calculation

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: NMinas Harutyunyan <hminas@synopsys.com>
Signed-off-by: NFelipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/dwc2/gadget.c

@@ -812,6 +812,7 @@ static int dwc2_gadget_fill_isoc_desc(struct dwc2_hsotg_ep *hs_ep,
 	u32 index;
 	u32 maxsize = 0;
 	u32 mask = 0;
+	u8 pid = 0;
 
 	maxsize = dwc2_gadget_get_desc_params(hs_ep, &mask);
 
@@ -840,7 +841,11 @@ static int dwc2_gadget_fill_isoc_desc(struct dwc2_hsotg_ep *hs_ep,
 			 ((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) |