On Mon. 6 Jun. 2022, at 05:46, Max Staudt <max@xxxxxxxxx> wrote: > > On Sun, 5 Jun 2022 20:06:41 +0200 > Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> wrote: > > > On 05.06.2022 19:23:47, Max Staudt wrote: > > > This seemingly splits drivers into "things that speak to hardware" > > > and "things that don't". Except... slcan really does speak to > > > hardware. slcan is just an oddity in this regard because all the netlink logic is done in userspace using slcand. I think that it would really benefit to be rewritten using the features under CAN_NETLINK. This way, it could for example benefit from can_priv::bitrate_const to manage the bitrates via iproute2 instead of relying on slcand c.f.: https://elinux.org/Bringing_CAN_interface_up#SLCAN_based_Interfaces Similarly, it doesn't seem that slcan loopbacks the TX frames which, in some way, violates one of the core concepts of SocketCAN: https://docs.kernel.org/networking/can.html#local-loopback-of-sent-frames You did a great job by putting all the logic in your can327 driver instead of requiring a userland tool and I think slcan merits to have your can327 improvements backported to him. > It just so happens to not use any of BITTIMING or > > > RX_OFFLOAD. However, my can327 (formerly elmcan) driver, which is > > > an ldisc just like slcan, *does* use RX_OFFLOAD, so where to I put > > > it? Next to flexcan, m_can, mcp251xfd and ti_hecc? > > > > > > Is it really just a split by features used in drivers, and no > > > longer a split by virtual/real? > > > > We can move RX_OFFLOAD out of the "if CAN_NETLINK". Who wants to > > create an incremental patch against can-next/master? > > Yes, this may be useful in the future. But for now, I think I can > answer my question myself :) I was about to answer you, but you corrected the shot before I had time to do so :) > My driver does support Netlink to set CAN link parameters. So I'll just > drop it into the CAN_NETLINK -> RX_OFFLOAD category in Kconfig, unless > anyone objects. This is the correct approach (and the only one). Try to maintain the alphabetical order of the menu when you add it. > I just got confused because in my mind, I'm still comparing it to > slcan, whereas in reality, it's now functionally closer to all the other > hardware drivers. Netlink and all. > > Apologies for the noise! No problem! Yours sincerely, Vincent Mailhol
