This patch fixes an issue that 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.
Fixes: e8d548d54968 ("usb: renesas_usbhs: fifo became independent from pipe.")
Cc: <sta...@vger.kernel.org> # v3.1+
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda...@renesas.com>
---
drivers/usb/renesas_usbhs/fifo.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/renesas_usbhs/fifo.c b/drivers/usb/renesas_usbhs/fifo.c
index 03cac07..68f2690 100644
--- a/drivers/usb/renesas_usbhs/fifo.c
+++ b/drivers/usb/renesas_usbhs/fifo.c
@@ -284,8 +284,17 @@ static void usbhsf_fifo_clear(struct usbhs_pipe *pipe,
struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
int ret = 0;
- if (!usbhs_pipe_is_dcp(pipe))
- ret = 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);
+ }
/*
* if non-DCP pipe, this driver should set BCLR when
--
1.9.1
