Hi Wolfram,
On Sun, Nov 6, 2016 at 9:20 PM, Wolfram Sang
<wsa+renesas@xxxxxxxxxxxxxxxxxxxx> wrote:
> From: Simon Horman <horms+renesas@xxxxxxxxxxxx>
>
> Make it possible to fallback to GPIO for I2C4 on the EXIO-E connector.
>
> This is based on reference work for the I2C0 core of the lager/r8a7790
> by Wolfram Sang.
>
> Signed-off-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
> [wsa: rebased and fixed aliases]
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> ---
> arch/arm/boot/dts/r8a7791-koelsch.dts | 35 +++++++++++++++++++++++++++++++++++
> 1 file changed, 35 insertions(+)
>
> diff --git a/arch/arm/boot/dts/r8a7791-koelsch.dts b/arch/arm/boot/dts/r8a7791-koelsch.dts
> index 8d653920957a4b..442d1512a8fa9c 100644
> --- a/arch/arm/boot/dts/r8a7791-koelsch.dts
> +++ b/arch/arm/boot/dts/r8a7791-koelsch.dts
> @@ -476,6 +501,11 @@
> function = "i2c2";
> };
>
> + i2c4_pins: i2c4 {
> + groups = "i2c4";
> + function = "i2c4";
> + };
> +
> du_pins: du {
> groups = "du_rgb888", "du_sync", "du_disp", "du_clk_out_0";
> function = "du";
> @@ -732,6 +762,11 @@
> clock-frequency = <100000>;
> };
>
> +&i2c4 {
> + pinctrl-0 = <&i2c4_pins>;
> + pinctrl-names = "i2c-exio4";
> +};
i2c4 shares pins with vin0. Hence enabling the former breaks the latter:
sh-pfc e6060000.pfc: pin GP_4_13 already requested by
e6520000.i2c; cannot claim for e6ef0000.video
sh-pfc e6060000.pfc: pin-141 (e6ef0000.video) status -22
sh-pfc e6060000.pfc: could not request pin 141 (GP_4_13) from
group vin0_data24 on device sh-pfc
rcar-vin e6ef0000.video: Error applying setting, reverse things back
rcar-vin: probe of e6ef0000.video failed with error -22
There may be similar issues on other boards. Haven't checked yet.
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
