On 10/20/2016 03:45 PM, Heiko Stübner wrote: > Am Donnerstag, 20. Oktober 2016, 10:07:25 schrieb Tomeu Vizoso: >> Add an empty 'i2c-bus' subnode to the edp node just so that the I2C core >> doesn't attemp to parse the 'ports' subnode as containing i2c devices. >> >> This is to avoid spurious failure messages such as: >> >> i2c i2c-6: of_i2c: modalias failure on /dp@ff970000/ports > > On the one hand, the edp really has an i2c bus - with its only client the > EDID > listening at 0x50 (and maybe 0x30). > > On the other hand, adding an empty bus to the (implementation independent) > devicetree just to make the Linux i2c subsystem happy sounds heavily like a > implementation-specific hack, as the edp i2c bus doesn't leak into the > outside > world otherwise. > > I guess this empty i2c bus not being part of the binding document points > heavily into the implementation-specific corner :-) . > > My short search on other patches touching this didn't reveal anything but > maybe this was already discussed somewhere and found to be ok?
Here it is: http://www.spinics.net/lists/linux-tegra/msg27862.html Regards, Tomeu > Another option could be to just make of_i2c_register_device silent if > of_modalias_node returns -ENODEV? > > > Heiko > >> Signed-off-by: Tomeu Vizoso <[email protected]> >> Cc: Randy Li <[email protected]> >> Cc: Jon Hunter <[email protected]> >> --- >> arch/arm/boot/dts/rk3288.dtsi | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/arch/arm/boot/dts/rk3288.dtsi b/arch/arm/boot/dts/rk3288.dtsi >> index 2f814ffeb605..94f4b7eecca2 100644 >> --- a/arch/arm/boot/dts/rk3288.dtsi >> +++ b/arch/arm/boot/dts/rk3288.dtsi >> @@ -1075,6 +1075,11 @@ >> }; >> }; >> }; >> + >> + i2c-bus { >> + #address-cells = <1>; >> + #size-cells = <0>; >> + }; >> }; >> >> hdmi: hdmi@ff980000 { >
