This patch fixes two issues:
- the usbhsf_fifo_clear() is possible to cause 10 msec delay if
the pipe is RX direction and empty because the FRDY bit will never
be set to 1 in such case.
- sets the BCLR of {C,Dn}FIFOCTR to 1 even when it's non-DCP pipe and
the FRDY bit sets to 0.
Fixes: e8d548d54968 ("usb: renesas_usbhs: fifo became independent from pipe.")
Cc: <stable@xxxxxxxxxxxxxxx> # v3.1+
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
---
This patch set is based on the Felipe's usb.git / testing/fixes branch
(The commit is 7661ca09b2ff98f48693f431bb01fed62830e433).
drivers/usb/renesas_usbhs/fifo.c | 21 ++++++++++++++++++---
1 file changed, 18 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/renesas_usbhs/fifo.c b/drivers/usb/renesas_usbhs/fifo.c
index d1af831..68f2690 100644
--- a/drivers/usb/renesas_usbhs/fifo.c
+++ b/drivers/usb/renesas_usbhs/fifo.c
@@ -282,11 +282,26 @@ static void usbhsf_fifo_clear(struct usbhs_pipe *pipe,
struct usbhs_fifo *fifo)
{
struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
+ int ret = 0;
- if (!usbhs_pipe_is_dcp(pipe))
- usbhsf_fifo_barrier(priv, fifo);
+ if (!usbhs_pipe_is_dcp(pipe)) {
+ /*
+ * This driver checks the pipe condition first to avoid -EBUSY
+ * from usbhsf_fifo_barrier() with about 10 msec delay in
+ * the interrupt handler if the pipe is RX direction and empty.
+ */
+ if (usbhs_pipe_is_dir_in(pipe))
+ ret = usbhs_pipe_is_accessible(pipe);
+ if (!ret)
+ ret = usbhsf_fifo_barrier(priv, fifo);
+ }
- usbhs_write(priv, fifo->ctr, BCLR);
+ /*
+ * if non-DCP pipe, this driver should set BCLR when
+ * usbhsf_fifo_barrier() returns 0.
+ */
+ if (!ret)
+ usbhs_write(priv, fifo->ctr, BCLR);
}
static int usbhsf_fifo_rcv_len(struct usbhs_priv *priv,
--
1.9.1