can: mcp251x: fix reception of standard RTR frames

This patch sets the missing CAN_RTR_FLAG if a standard RTR frame is
received.
(For extended frames the CAN_RTR_FLAG was already set correctly.)

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/net/can/mcp251x.c b/drivers/net/can/mcp251x.c
index 6aadc3e32bd5..7ab534aee452 100644
--- a/drivers/net/can/mcp251x.c
+++ b/drivers/net/can/mcp251x.c
@@ -169,6 +169,7 @@
 #  define RXBSIDH_SHIFT 3
 #define RXBSIDL(n)  (((n) * 0x10) + 0x60 + RXBSIDL_OFF)
 #  define RXBSIDL_IDE   0x08
+#  define RXBSIDL_SRR   0x10
 #  define RXBSIDL_EID   3
 #  define RXBSIDL_SHIFT 5
 #define RXBEID8(n)  (((n) * 0x10) + 0x60 + RXBEID8_OFF)
@@ -475,6 +476,8 @@ static void mcp251x_hw_rx(struct spi_device *spi, int buf_idx)
                 frame->can_id =
                         (buf[RXBSIDH_OFF] << RXBSIDH_SHIFT) |
                         (buf[RXBSIDL_OFF] >> RXBSIDL_SHIFT);
+                if (buf[RXBSIDL_OFF] & RXBSIDL_SRR)
+                        frame->can_id |= CAN_RTR_FLAG;
         }
         /* Data length */
         frame->can_dlc = get_can_dlc(buf[RXBDLC_OFF] & RXBDLC_LEN_MASK);