e3b0a4a470
When the FD is turned off through the netlink interface, the data bit timing values still remain in data_bittiming and are displayed despite of the feature being disabled. Example: | $ ip link set can0 type can bitrate 500000 dbitrate 2000000 fd on | $ ip --details link show can0 | 1: can0: <NOARP,ECHO> mtu 72 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 10 | link/can promiscuity 0 minmtu 0 maxmtu 0 | can <FD> state STOPPED restart-ms 0 | bitrate 500000 sample-point 0.875 | tq 12 prop-seg 69 phase-seg1 70 phase-seg2 20 sjw 1 | ES582.1/ES584.1: tseg1 2..256 tseg2 2..128 sjw 1..128 brp 1..512 brp-inc 1 | dbitrate 2000000 dsample-point 0.750 | dtq 12 dprop-seg 14 dphase-seg1 15 dphase-seg2 10 dsjw 1 | ES582.1/ES584.1: dtseg1 2..32 dtseg2 1..16 dsjw 1..8 dbrp 1..32 dbrp-inc 1 | clock 80000000 numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 | | $ ip link set can0 type can bitrate 500000 fd off | $ ip --details link show can0 | 1: can0: <NOARP,ECHO> mtu 16 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 10 | link/can promiscuity 0 minmtu 0 maxmtu 0 | can state STOPPED restart-ms 0 | bitrate 500000 sample-point 0.875 | tq 12 prop-seg 69 phase-seg1 70 phase-seg2 20 sjw 1 | ES582.1/ES584.1: tseg1 2..256 tseg2 2..128 sjw 1..128 brp 1..512 brp-inc 1 | dbitrate 2000000 dsample-point 0.750 | dtq 12 dprop-seg 14 dphase-seg1 15 dphase-seg2 10 dsjw 1 | ES582.1/ES584.1: dtseg1 2..32 dtseg2 1..16 dsjw 1..8 dbrp 1..32 dbrp-inc 1 | clock 80000000 numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 Remark: once FD is turned off, it is not possible to turn fd back on and reuse the previously input data bit timing values: | $ ip link set can0 type can bitrate 500000 fd on | RTNETLINK answers: Operation not supported This means that the user will need to re-configure the data bit timing in order to turn fd on again. Because old data bit timing values cannot be reused, this patch clears priv->data_bit timing whenever FD is turned off. This way, the data bit timing variables are not displayed anymore. Link: https://lore.kernel.org/r/20210618081904.141114-2-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.