CAN RAW sockets allow userspace to tell if a received CAN frame comes
from the same socket, another socket on the same host, or another host.
See commit 1e55659ce6 ("can-raw: add msg_flags to distinguish local
traffic"). However, this feature is missing in CAN BCM sockets.
Add the same feature to CAN BCM sockets. When reading a received frame
(opcode RX_CHANGED) using recvmsg, two flags in msg->msg_flags may be
set following the previous convention (from CAN RAW), to distinguish
between 'own', 'local' and 'remote' CAN traffic.
Update the documentation to reflect this change.
Signed-off-by: Nicolas Maier <nicolas.maier.dev@gmail.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20240120081018.2319-1-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Correct spelling problems for Documentation/networking/ as reported
by codespell.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Jiri Pirko <jiri@nvidia.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: netdev@vger.kernel.org
Link: https://lore.kernel.org/r/20230129231053.20863-5-rdunlap@infradead.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add documentation for how to use and setup the switchable termination
resistor support for CAN controllers.
Signed-off-by: Daniel Trevitz <dan@sstrev.com>
Link: https://lore.kernel.org/all/3441354.44csPzL39Z@daniel6430
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
There are two sections called "Local Loopback of Sent Frames". One was
meant to link to the other, but pointed at itself instead.
Link: https://lore.kernel.org/all/20220611171155.9090-1-max@enpas.org
Fixes: 7d59773945 ("can: migrate documentation to restructured text")
Signed-off-by: Max Staudt <max@enpas.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Some parts of the documentation may lead the reader to think that the
socket's own frames are always received when CAN_RAW_RECV_OWN_MSGS is
enabled, but all frames are subject to filtering.
As explained by Marc Kleine-Budde:
On TX complete of a CAN frame it's pushed into the RX path of the
networking stack, along with the information of the originating socket.
Then the CAN frame is delivered into AF_CAN, where it is passed on to
all registered receivers depending on filters. One receiver is the
sending socket in CAN_RAW. Then in CAN_RAW the it is checked if the
sending socket has RECV_OWN_MSGS enabled.
Link: https://lore.kernel.org/r/20210420191212.42753-1-erik@flodin.me
Signed-off-by: Erik Flodin <erik@flodin.me>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The extension of struct can_frame with the len8_dlc element and the
can_dlc naming issue required an update of the documentation.
Additionally introduce the term 'Classical CAN' which has been established
by CAN in Automation to separate the original CAN2.0 A/B from CAN FD.
Updated some data structures and flags.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-7-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The helper functions can_len2dlc and can_dlc2len are only relevant for
CAN FD data length code (DLC) conversion.
To fit the introduced can_cc_dlc2len for Classical CAN we rename:
can_dlc2len -> can_fd_dlc2len to get the payload length from the DLC
can_len2dlc -> can_fd_len2dlc to get the DLC from the payload length
Suggested-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-6-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
- add SPDX header;
- adjust title markup;
- mark lists as such;
- adjust identation, whitespaces and blank lines;
- add to networking/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
As stated at:
http://www.sphinx-doc.org/en/master/usage/restructuredtext/basics.html#footnotes
A footnote should contain either a number, a reference or
an auto number, e. g.:
[1], [#f1] or [#].
While using [*] accidentaly works for html, it fails for other
document outputs. In particular, it causes an error with LaTeX
output, causing all books after networking to not be built.
So, replace it by a valid syntax.
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
The kernel documentation is now restructured text. Convert the SocketCAN
documentation and include it in the toplevel kernel documentation.
This patch doesn't do any content change.
All references to can.txt in the code are converted to can.rst.
Signed-off-by: Robert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
