[PATCH AUTOSEL for 4.4 130/167] [media] mceusb: sporadic RX truncation corruption fix

Sasha Levin
2018-03-19T17:08:44Z

From: A Sun <as1033x@comcast.net>

[ Upstream commit 8e175b22e8640bf3a58e071af54190b909e4a944 ]

Intermittent RX truncation and loss of IR received data. This resulted
in receive stream synchronization errors where driver attempted to
incorrectly parse IR data (eg 0x90 below) as command response.

[ 3969.139898] mceusb 1-1.2:1.0: processed IR data
[ 3969.151315] mceusb 1-1.2:1.0: rx data: 00 90 (length=2)
[ 3969.151321] mceusb 1-1.2:1.0: Unknown command 0x00 0x90
[ 3969.151336] mceusb 1-1.2:1.0: rx data: 98 0a 8d 0a 8e 0a 8e 0a 8e 0a 8e 0a 9a 0a 8e 0a 0b 3a 8e 00 80 41 59 00 00 (length=25)
[ 3969.151341] mceusb 1-1.2:1.0: Raw IR data, 24 pulse/space samples
[ 3969.151348] mceusb 1-1.2:1.0: Storing space with duration 500000

Bug trigger appears to be normal, but heavy, IR receiver use.

Signed-off-by: A Sun <as1033x@comcast.net>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
drivers/media/rc/mceusb.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/media/rc/mceusb.c b/drivers/media/rc/mceusb.c
index f838d9c7ed12..0fba4a2c1602 100644
--- a/drivers/media/rc/mceusb.c
+++ b/drivers/media/rc/mceusb.c
@@ -1370,8 +1370,13 @@ static int mceusb_dev_probe(struct usb_interface *intf,
goto rc_dev_fail;

/* wire up inbound data handler */
- usb_fill_int_urb(ir->urb_in, dev, pipe, ir->buf_in, maxp,
- mceusb_dev_recv, ir, ep_in->bInterval);
+ if (usb_endpoint_xfer_int(ep_in))
+ usb_fill_int_urb(ir->urb_in, dev, pipe, ir->buf_in, maxp,
+ mceusb_dev_recv, ir, ep_in->bInterval);
+ else
+ usb_fill_bulk_urb(ir->urb_in, dev, pipe, ir->buf_in, maxp,
+ mceusb_dev_recv, ir);
+
ir->urb_in->transfer_dma = ir->dma_in;
ir->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

--
2.14.1