Commit Graph

22 Commits

Author SHA1 Message Date
Vincent Mailhol
6153a7ea65 can: slcan: add software tx timestamps
TX timestamps were added to the can_put_echo_skb() function of can_dev
modules in [1]. However, slcan does not rely on that function and as
such does not offer TX timestamping.

Add a call to skb_tx_timestamp() in the slc_xmit() function so that
the module now supports TX software timestamps.

[1] commit 741b91f1b0 ("can: dev: can_put_echo_skb(): add software
tx timestamps")
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=741b91f1b0ea34f00f6a7d4539b767c409291fcf

CC: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/all/20220727101641.198847-4-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28 09:30:36 +02:00
Dario Binacchi
4aeccfd84d MAINTAINERS: Add maintainer for the slcan driver
At the suggestion of its author Oliver Hartkopp ([1]), I take over the
maintainer-ship and add myself to the authors of the driver.

[1] https://lore.kernel.org/all/507b5973-d673-4755-3b64-b41cb9a13b6f@hartkopp.net

Suggested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Link: https://lore.kernel.org/all/20220728070254.267974-8-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28 09:14:42 +02:00
Dario Binacchi
3e72013196 can: slcan: add support for listen-only mode
For non-legacy, i.e. ip based configuration, add support for listen-only
mode. If listen-only is requested send a listen-only ("L\r") command
instead of an open ("O\r") command to the adapter.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Link: https://lore.kernel.org/all/20220728070254.267974-7-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28 09:14:42 +02:00
Dario Binacchi
341c5724d7 can: slcan: use the generic can_change_mtu()
It is useless to define a custom function that does nothing but always
return the same error code. Better to use the generic can_change_mtu()
function.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Link: https://lore.kernel.org/all/20220728070254.267974-6-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28 09:14:42 +02:00
Dario Binacchi
0cef03b109 can: slcan: change every slc' occurrence in slcan'
In the driver there are parts of code where the prefix `slc' is used and
others where the prefix `slcan' is used instead. The patch replaces
every occurrence of `slc' with `slcan', except for the netdev functions
where, to avoid compilation conflicts, it was necessary to replace `slc'
with `slcan_netdev'.

The patch does not make any functional changes.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Link: https://lore.kernel.org/all/20220728070254.267974-5-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28 09:14:35 +02:00
Dario Binacchi
cfcb4465e9 can: slcan: remove legacy infrastructure
Taking inspiration from the drivers/net/can/can327.c driver and at the
suggestion of its author Max Staudt, I removed legacy stuff like
`SLCAN_MAGIC' and `slcan_devs' resulting in simplification of the code
and its maintainability.

The use of slcan_devs is derived from a very old kernel, since slip.c
is about 30 years old, so today's kernel allows us to remove it.

The .hangup() ldisc function, which only called the ldisc .close(), has
been removed since the ldisc layer calls .close() in a good place
anyway.

The old slcanX name has been dropped in order to use the standard canX
interface naming. The ioctl SIOCGIFNAME can be used to query the name of
the created interface. Furthermore, there are several ways to get stable
interfaces names in user space, e.g. udev or systemd-networkd.

The `maxdev' module parameter has also been removed.

CC: Max Staudt <max@enpas.org>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Reviewed-by: Max Staudt <max@enpas.org>
Link: https://lore.kernel.org/all/20220728070254.267974-4-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28 09:13:11 +02:00
Dario Binacchi
7a1fc3eea7 can: slcan: remove useless header inclusions
Include only the necessary headers.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Link: https://lore.kernel.org/all/20220728070254.267974-3-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28 09:10:47 +02:00
Vincent Mailhol
e2c9bb0297 can: slcan: use KBUILD_MODNAME and define pr_fmt to replace hardcoded names
The driver uses the string "slcan" to populate
tty_ldisc_ops::name. KBUILD_MODNAME also evaluates to "slcan". Use
KBUILD_MODNAME to get rid on the hardcoded string names.

Similarly, the pr_info() and pr_err() hardcoded the "slcan"
prefix. Define pr_fmt so that the "slcan" prefix gets automatically
added.

CC: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Link: https://lore.kernel.org/all/20220728070254.267974-2-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28 09:10:47 +02:00
Vincent Mailhol
1851532fd3 can: slcan: export slcan_ethtool_ops and remove slcan_set_ethtool_ops()
The function slcan_set_ethtool_ops() does one thing: populate
net_device::ethtool_ops. Instead, it is possible to directly assign
this field and remove one function call and slightly reduce the object
size. To do so, export slcan_ethtool_ops so it becomes visible to
sclan-core.c.

This patch reduces the footprint by 14 bytes:

| $ ./scripts/bloat-o-meter drivers/net/can/slcan/slcan.{old,new}.o
| drivers/net/can/slcan/slcan.o
| add/remove: 0/1 grow/shrink: 1/0 up/down: 15/-29 (-14)
| Function                                     old     new   delta
| slcan_open                                  1010    1025     +15
| slcan_set_ethtool_ops                         29       -     -29
| Total: Before=11115, After=11101, chg -0.13%

Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/all/20220727104939.279022-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-27 13:09:01 +02:00
Vincent Mailhol
3e5c291c79 can: add CAN_ERR_CNT flag to notify availability of error counter
Add a dedicated flag in uapi/linux/can/error.h to notify the userland
that fields data[6] and data[7] of the CAN error frame were
respectively populated with the tx and rx error counters.

For all driver tree-wide, set up this flags whenever needed.

Link: https://lore.kernel.org/all/20220719143550.3681-12-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-20 09:27:37 +02:00
Vincent Mailhol
ce0e7aeb67 can: slcan: do not report txerr and rxerr during bus-off
During bus off, the error count is greater than 255 and can not fit in
a u8.

alloc_can_err_skb() already sets cf to NULL if the allocation fails [1],
so the redundant cf = NULL assignment gets removed.

[1] https://elixir.bootlin.com/linux/latest/source/drivers/net/can/dev/skb.c#L187

Fixes: 0a9cdcf098 ("can: slcan: extend the protocol with CAN state info")
Link: https://lore.kernel.org/all/20220719143550.3681-5-mailhol.vincent@wanadoo.fr
CC: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-20 09:26:49 +02:00
Dario Binacchi
c688702326 can: slcan: do not sleep with a spin lock held
We can't call close_candev() with a spin lock held, so release the lock
before calling it. After calling close_candev(), we can update the
fields of the private `struct can_priv' without having to acquire the
lock.

Fixes: c4e54b063f ("can: slcan: use CAN network device driver API")
Link: https://lore.kernel.org/linux-kernel/Ysrf1Yc5DaRGN1WE@xsang-OptiPlex-9020/
Link: https://lore.kernel.org/all/20220715072951.859586-1-dario.binacchi@amarulasolutions.com
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-19 20:54:53 +02:00
Marc Kleine-Budde
18de712a58 can: slcan: clean up if/else
Remove braces after if() for single statement blocks, also remove else
after return() in if() block.

Link: https://lore.kernel.org/all/20220704125954.1587880-6-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-19 20:30:14 +02:00
Marc Kleine-Budde
69a6539632 can: slcan: convert comparison to NULL into !val
All comparison to NULL could be written "!val", convert them to make
checkpatch happy.

Link: https://lore.kernel.org/all/20220704125954.1587880-5-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-19 20:30:14 +02:00
Marc Kleine-Budde
f07d9e3c84 can: slcan: fix whitespace issues
Add and remove whitespace to make checkpatch happy.

Link: https://lore.kernel.org/all/20220704125954.1587880-4-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-19 20:30:14 +02:00
Marc Kleine-Budde
ded5fa885b can: slcan: slcan_init() convert printk(LEVEL ...) to pr_level()
Convert the last printk(LEVEL ...) to pr_level().

Link: https://lore.kernel.org/all/20220704125954.1587880-3-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-19 20:30:14 +02:00
Marc Kleine-Budde
71f3a4cc74 can: slcan: convert comments to network style comments
Convert all comments to network subsystem style comments.

Link: https://lore.kernel.org/all/20220704125954.1587880-2-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-19 20:30:14 +02:00
Dan Carpenter
0159a9305d can: slcan: use scnprintf() as a hardening measure
The snprintf() function returns the number of bytes which *would* have
been copied if there were no space. So, since this code does not check
the return value, there if the buffer was not large enough then there
would be a buffer overflow two lines later when it does:

	actual = sl->tty->ops->write(sl->tty, sl->xbuff, n);

Use scnprintf() instead because that returns the number of bytes which
were actually copied.

Fixes: 52f9ac85b8 ("can: slcan: allow to send commands to the adapter")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/all/YsVA9KoY/ZSvNGYk@kili
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-19 20:29:36 +02:00
Dario Binacchi
0a9cdcf098 can: slcan: extend the protocol with CAN state info
It extends the protocol to receive the adapter CAN state changes
(warning, busoff, etc.) and forward them to the netdev upper levels.

Link: https://lore.kernel.org/all/20220628163137.413025-13-dario.binacchi@amarulasolutions.com
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-03 11:34:45 +02:00
Dario Binacchi
b32ff46685 can: slcan: extend the protocol with error info
It extends the protocol to receive the adapter CAN communication errors
and forward them to the netdev upper levels.

Link: https://lore.kernel.org/all/20220628163137.413025-12-dario.binacchi@amarulasolutions.com
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-03 11:34:44 +02:00
Dario Binacchi
4de0e8efa0 can: slcan: add ethtool support to reset adapter errors
This patch adds a private flag to the slcan driver to switch the
"err-rst-on-open" setting on and off.

"err-rst-on-open" on  - Reset error states on opening command

"err-rst-on-open" off - Don't reset error states on opening command
                        (default)

The setting can only be changed if the interface is down:

    ip link set dev can0 down
    ethtool --set-priv-flags can0 err-rst-on-open {off|on}
    ip link set dev can0 up

Link: https://lore.kernel.org/all/20220628163137.413025-11-dario.binacchi@amarulasolutions.com
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-03 11:34:44 +02:00
Dario Binacchi
98b1206459 can: slcan: move driver into separate sub directory
This patch moves the slcan driver into a separate directory, a later
patch will add more files.

Link: https://lore.kernel.org/all/20220628163137.413025-10-dario.binacchi@amarulasolutions.com
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-03 11:34:44 +02:00