Re: [PATCH V11 3/5] kbuild: Allow .dtso format for overlay source files

[Geert Uytterhoeven]

Hi Frank,

On Tue, Mar 16, 2021 at 6:39 AM Frank Rowand <frowand.list@xxxxxxxxx> wrote:
> On 3/15/21 5:12 PM, Laurent Pinchart wrote:
> > On Tue, Mar 16, 2021 at 02:43:45AM +0900, Masahiro Yamada wrote:
> >> But how can we fix drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a779*.dts
> >> if these are doing bad things.
> >> They seem to be overlay files even though the file name suffix is .dts
> >
> > That is correct, they are overlays. I have no issue with those files
> > being renamed to .dtso if that can help (but I haven't checked if that
> > would have any adverse effect on the R-Car DU driver).
>
> As Laurent replied, yes these are overlays.  They were grandfathered in
> as a deprecated use of overlays.
>
> > These files are there to ensure backward compatibility with older DT
> > bindings. The change was made 3 years ago and I wouldn't object to
> > dropping this completely, but I understand I may not be the most
> > cautious person when it comes to ensuring DT backward compatibility :-)
>
> My memory is that the goal was to eventually remove these overlays
> at some point in the future.  If everyone agrees that today is the
> proper time, it would be helpful to go ahead and remove these .dts
> files and the code that uses them.

Given [1][2][3] were merged in v4.17, and [4] was merged in v4.20, and
all were backported to the old v4.14-based R-Car BSP v3.8.0, I think
it's safe to assume all users have the DTS updates, so the backward
compatibility mode can be removed?

> >> drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7791.dts
> >> drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7795.dts
> >> drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7796.dts
> >> drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7793.dts
> >> drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7790.dts

[1] 15a1ff30d8f9bd83 ("ARM: dts: r8a7790: Convert to new LVDS DT bindings")
[2] e5c3f4707f3956a2 ("ARM: dts: r8a7791: Convert to new LVDS DT bindings")
[3] edb0c3affe5214a2 ("ARM: dts: r8a7793: Convert to new LVDS DT bindings")
[4] 58e8ed2ee9abe718 ("arm64: dts: renesas: Convert to new LVDS DT bindings")

Gr{oetje,eeting}s,

                        Geert


--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds