4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Kazuya Mizuguchi <kazuya.mizuguchi.ks@xxxxxxxxxxx>
commit 29c7f3e68eec4ae94d85ad7b5dfdafdb8089f513 upstream.
The DREQE bit of the DnFIFOSEL should be set to 1 after the DE bit of
USB-DMAC on R-Car SoCs is set to 1 after the USB-DMAC received a
zero-length packet. Otherwise, a transfer completion interruption
of USB-DMAC doesn't happen. Even if the driver changes the sequence,
normal operations (transmit/receive without zero-length packet) will
not cause any side-effects. So, this patch fixes the sequence anyway.
Signed-off-by: Kazuya Mizuguchi <kazuya.mizuguchi.ks@xxxxxxxxxxx>
[shimoda: revise the commit log]
Fixes: e73a9891b3a1 ("usb: renesas_usbhs: add DMAEngine support")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/renesas_usbhs/fifo.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/usb/renesas_usbhs/fifo.c
+++ b/drivers/usb/renesas_usbhs/fifo.c
@@ -858,9 +858,9 @@ static void xfer_work(struct work_struct
fifo->name, usbhs_pipe_number(pipe), pkt->length, pkt->zero);
usbhs_pipe_running(pipe, 1);
- usbhsf_dma_start(pipe, fifo);
usbhs_pipe_set_trans_count_if_bulk(pipe, pkt->trans);
dma_async_issue_pending(chan);
+ usbhsf_dma_start(pipe, fifo);
usbhs_pipe_enable(pipe);
xfer_work_end: