From 72d92e865d1560723e1957ee3f393688c49ca5bf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20M=C3=A4tje?= <Stefan.Maetje@esd.eu>
Date: Wed, 18 Oct 2017 13:25:17 +0200
Subject: [PATCH] can: esd_usb2: Fix can_dlc value for received RTR, frames
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Git-commit: 72d92e865d1560723e1957ee3f393688c49ca5bf
Patch-mainline: v4.14-rc6
References: bsc#1051510

The dlc member of the struct rx_msg contains also the ESD_RTR flag to
mark received RTR frames. Without the fix the can_dlc value for received
RTR frames would always be set to 8 by get_can_dlc() instead of the
received value.

Fixes: 96d8e90382dc ("can: Add driver for esd CAN-USB/2 device")
Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/can/usb/esd_usb2.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/can/usb/esd_usb2.c
+++ b/drivers/net/can/usb/esd_usb2.c
@@ -333,7 +333,7 @@ static void esd_usb2_rx_can_msg(struct e
 		}
 
 		cf->can_id = id & ESD_IDMASK;
-		cf->can_dlc = get_can_dlc(msg->msg.rx.dlc);
+		cf->can_dlc = get_can_dlc(msg->msg.rx.dlc & ~ESD_RTR);
 
 		if (id & ESD_EXTID)
 			cf->can_id |= CAN_EFF_FLAG;