[0/2] i2c: Add new driver for Renesas RZ/V2M controller

Message

Phil Edworthy June 24, 2022, 10:17 a.m. UTC

Hi,

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.

Phil Edworthy (2):
  dt-bindings: i2c: Document RZ/V2M I2C controller
  i2c: Add Renesas RZ/V2M controller

 .../bindings/i2c/renesas,rzv2m.yaml           |  76 +++
 drivers/i2c/busses/Kconfig                    |  10 +
 drivers/i2c/busses/Makefile                   |   1 +
 drivers/i2c/busses/i2c-rzv2m.c                | 530 ++++++++++++++++++
 4 files changed, 617 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/i2c/renesas,rzv2m.yaml
 create mode 100644 drivers/i2c/busses/i2c-rzv2m.c

Comments

Geert Uytterhoeven June 24, 2022, 11:18 a.m. UTC | #1

Hi Phil,

Thanks for your series!

On Fri, Jun 24, 2022 at 12:17 PM Phil Edworthy
<[e-mail]> 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.

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 -- [e-mail]

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