Hi Philipp,
On Wed, Jun 29, 2022 at 6:21 PM Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> wrote:
> On Di, 2022-06-28 at 20:45 +0100, Phil Edworthy wrote:
> > The Renesas RZ/V2M SoC (r9a09g011) has a new i2c controller. This series
> > add the driver. One annoying problem is that the SoC uses a single reset
> > line for two i2c controllers, and unfortunately one of the controllers
> > is managed by some firmware, not by Linux. Therefore, the driver just
> > deasserts the reset.
>
> This sounds scary. If the driver is never loaded, and the reset is
> never deasserted, what happens to the firmware trying to access the
> other i2c controller? Does it hang? Or write to the reset controller
> registers to deassert the reset? If so, is there any protection against
> concurrent access from firmware and reset controller driver?
In response to v1, I wrote
| That is actually an integration issue, not an i2c controller issue.
|
| Perhaps we need a RESET_IS_CRITICAL flag, cfr. CLK_IS_CRITICAL,
| to be set by the reset provider?
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
