[PATCH 4.14 048/217] dwc2: gadget: Fix ISOC IN DDMA PID bitfield value calculation

Greg Kroah-Hartman
2018-08-23T08:22:10Z

From: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>

[ 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@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
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
@@ -848,6 +848,7 @@ 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) {
@@ -893,7 +894,11 @@ 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) |