If we look closely, the 4 writes to TRANSMIT_CHL.id1 can be collapsed
down into much simpler code.  So do just that.

This also fixes a build failure due to the I/O macros no longer
getting pulled in.  Their minor (and accidental) usage here gets
dropped as part of the unification.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Acked-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that core network takes care of trans_start updates, dont do it
in drivers themselves, if possible. Drivers can avoid one cache miss
(on dev->trans_start) in their start_xmit() handler.

Exceptions are NETIF_F_LLTX drivers
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the current implementation, CAN drivers need to #include <linux/can.h>
_before_ they #include <linux/can/dev.h>, which is both ugly and
unnecessary.

Fix this by including <linux/can.h> in <linux/can/dev.h> and remove the
#include <linux/can.h> lines from drivers.
Signed-off-by: NHans J. Koch <hjk@linutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The MMR bits are being moved to this header, so include it.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Looks like commit a6e4bc53 didn't include updates to drivers so the
Blackfin CAN driver fails to build now.
Signed-off-by: NBarry Song <barry.song@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds error checking of ctrlmode values for CAN devices. As
an example all availabe bits are implemented in the mcp251x driver.
Signed-off-by: NChristian Pellegrin <chripell@fsfe.org>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To prevent the CAN drivers to operate on invalid socketbuffers the skbs are
now checked and silently dropped at the xmit-function consistently.

Also the netdev stats are consistently using the CAN data length code (dlc)
for [rx|tx]_bytes now.
Signed-off-by: NOliver Hartkopp <oliver@hartkopp.net>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A valid CAN dataframe can have a data length code (DLC) of 0 .. 8 data bytes.

When reading the CAN controllers register the 4-bit value may contain values
from 0 .. 15 which may exceed the reserved space in the socket buffer!

The ISO 11898-1 Chapter 8.4.2.3 (DLC field) says that register values > 8
should be reduced to 8 without any error reporting or frame drop.

This patch introduces a new helper macro to cast a given 4-bit data length
code (dlc) to __u8 and ensure the DLC value to be max. 8 bytes.

The different handlings in the rx path of the CAN netdevice drivers are fixed.
Signed-off-by: NOliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBarry Song <21cnbao@gmail.com>
Signed-off-by: NH.J. Oertel <oe@port.de>
Signed-off-by: NWolfgang Grandegger <wg@grandegger.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>