[PATCH 4.4 041/113] usb: renesas_usbhs: Use dmac only if the pipe type is bulk

Greg Kroah-Hartman
2016-09-05T16:51:23Z

From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

commit 700aa7ff8d2c2b9cc669c99375e2ccd06d3cd38d upstream.

This patch fixes an issue that isochronous transfer's data is possible to
be lost as a workaround. Since this driver uses a workqueue to start
the dmac, the transfer is possible to be delayed when system load is high.

Fixes: 6e4b74e4690d ("usb: renesas: fix scheduling in atomic context bug")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/renesas_usbhs/fifo.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/usb/renesas_usbhs/fifo.c
+++ b/drivers/usb/renesas_usbhs/fifo.c
@@ -869,7 +869,7 @@ static int usbhsf_dma_prepare_push(struc

/* use PIO if packet is less than pio_dma_border or pipe is DCP */
if ((len < usbhs_get_dparam(priv, pio_dma_border)) ||
- usbhs_pipe_is_dcp(pipe))
+ usbhs_pipe_type_is(pipe, USB_ENDPOINT_XFER_ISOC))
goto usbhsf_pio_prepare_push;

/* check data length if this driver don't use USB-DMAC */
@@ -974,7 +974,7 @@ static int usbhsf_dma_prepare_pop_with_u

/* use PIO if packet is less than pio_dma_border or pipe is DCP */
if ((pkt->length < usbhs_get_dparam(priv, pio_dma_border)) ||
- usbhs_pipe_is_dcp(pipe))
+ usbhs_pipe_type_is(pipe, USB_ENDPOINT_XFER_ISOC))
goto usbhsf_pio_prepare_pop;

fifo = usbhsf_get_dma_fifo(priv, pkt);