can, tcan4x5x: look to merge rpi support into rpi kernel tree

[Phil Elwell]

Hi Torin,

On Fri, 12 Feb 2021 at 13:20, Nicolas Saenz Julienne
<nsaenzjulienne at suse.de> wrote:
>
> On Fri, 2021-02-12 at 10:01 +0000, Torin Cooper-Bennun wrote:
> > The Texas Instruments CAN-FD controller, TCAN4550, has kernel support in the
> > tcan4x5x module.
> >
> > Until a recent patch, Raspberry Pi was unable to utilise the driver, as the
> > module supported only SPI controllers with native 32-bit word support (we
> > only have 8-bit support).
> >
> > Said patch was merged into net-next in pull request c10b377ff6, which also
> > includes a larger rework of tcan4x5x:
> > https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=c10b377ff670744e1f04f902ff4fe47ea8dd32bd
> >
> > What's the protocol for merging patches like this into the rpi kernel tree?
> > Are mainline changes the only changes merged in?
>
> AFAIK the RPi downstream tree only tracks whatever appears in Linus' kernel
> tree. So you'll have to wait until that happens. And even then, the patches
> will only be available in the downstream tree. They still have to package it
> and distribute it. Version bumps happen every so often, so you'll have to be
> patient.
>
> If it's really urgent to you, I suggest you backport the patches and send a
> pull request to the current downstream branch being released at the moment (I
> think it's rpi-5.10.y). Then you'll have to persuade them to accept it, but
> that's on you :).

We are usually happy to accept backports once the commits have been
merged upstream. Just create an issue at
https://github.com/raspberrypi/linux/issues saying what you want and
why, and you should have a fairly prompt response.

Phil