This is a note to let you know that I've just added the patch titled
usb: renesas_usbhs: fix usbhsf_fifo_clear() for RX direction
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 0a2ce62b61f2c76d0213edf4e37aaf54a8ddf295 Mon Sep 17 00:00:00 2001
From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Date: Wed, 27 Sep 2017 18:47:13 +0900
Subject: usb: renesas_usbhs: fix usbhsf_fifo_clear() for RX direction
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: <stable@xxxxxxxxxxxxxxx> # v3.1+
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
---
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 03cac07f57b5..68f26904c316 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
--
2.14.1