Re: [PATCH v3] reset: Exclusive resets must be dedicated to a single hardware block

[Geert Uytterhoeven]

On Tue, Nov 13, 2018 at 2:35 PM Geert Uytterhoeven
<geert+renesas@xxxxxxxxx> wrote:
> In some SoCs multiple hardware blocks may share a reset control.
> The reset control API for shared resets will only assert such a reset
> when the drivers for all hardware blocks agree.
> The exclusive reset control API still allows to assert such a reset, but
> that impacts all other hardware blocks sharing the reset.
>
> While the kernel doc comments clearly state that the API for shared
> resets applies to reset controls which are shared between hardware
> blocks, the exact meaning of exclusive resets is not documented.
> Fix the semantic ambiguity with respect to exclusive access vs.
> exclusive reset lines by:
>   1. Clarifying that exclusive resets really are intended for use with
>      reset controls which are dedicated to a single hardware block,
>   2. Ensuring that obtaining an exclusive reset control will fail if the
>      reset is shared by multiple hardware blocks, for both DT-based and
>      lookup-based reset controls.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
> Question from Philipp for the DT maintainers:
>
>    "I'd still like to hear the device tree maintainers' opinion on
>     parsing the whole DT for "resets" phandle properties to find shared
>     resets like this."

Mark, Rob: Ping?

Thanks!

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