Patch "usb: renesas_usbhs: fix usbhsf_fifo_clear() for RX direction" has been added to the 4.4-stable tree

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 the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
usb-renesas_usbhs-fix-usbhsf_fifo_clear-for-rx-direction.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Yoshihiro Shimoda <[email protected]>
Date: Wed, 27 Sep 2017 18:47:13 +0900
Subject: usb: renesas_usbhs: fix usbhsf_fifo_clear() for RX direction

From: Yoshihiro Shimoda <[email protected]>

commit 0a2ce62b61f2c76d0213edf4e37aaf54a8ddf295 upstream.

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.

---
 drivers/usb/renesas_usbhs/fifo.c |   13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

@@ -287,8 +287,17 @@ static void usbhsf_fifo_clear(struct usb
 	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

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/usb-renesas_usbhs-fix-usbhsf_fifo_clear-for-rx-direction.patch queue-4.4/usb-renesas_usbhs-fix-the-bclr-setting-condition-for-non-dcp-pipe.patch