On 09/19/2013 03:01 PM, Srinivas KANDAGATLA wrote: > On 19/09/13 08:16, Maxime COQUELIN wrote: >> Hi Srini, >> >> On 09/18/2013 03:17 PM, Srinivas KANDAGATLA wrote: >>> On 18/09/13 13:46, Maxime COQUELIN wrote: >>>> On 09/18/2013 02:03 PM, Lee Jones wrote: >>>>>>>> This patch supplies I2C configuration to STiH416 SoC. >>>>>>>> >>>>>>>> Cc: Srinivas Kandagatla <srinivas.kandagatla@xxxxxx> >>>>>>>> Signed-off-by: Maxime Coquelin <maxime.coquelin@xxxxxx> >>>>>>>> --- >>>>>>>> arch/arm/boot/dts/stih416-pinctrl.dtsi | 35 ++++++++++++++++++++ >>>>>>>> arch/arm/boot/dts/stih416.dtsi | 57 ++++++++++++++++++++++++++++++++ >>>>>>>> 2 files changed, 92 insertions(+) >>>>>>>> >>>>>>>> diff --git a/arch/arm/boot/dts/stih416-pinctrl.dtsi b/arch/arm/boot/dts/stih416-pinctrl.dtsi >>>>>> I genuinely don't know the answer to this question, but are these >>>>>> nodes identical to the ones you've just put in the stih415 DTSI file? >>>>>> If so, I think it will be worth creating a stih41x DTSI rather than >>>>>> duplicating lots of stuff unnecessarily. >>>> There are close to be identical indeed. >>>> For the clocks and pinctrl, the references names are the same, but they are >>>> pointing on different nodes, as STiH415 and STiH416 have their own >>>> clocks and pinctrl dtsi files. >>>> >>>> Srini, what is opinion about this? >>> There is already a stih41x.dtsi file, but I don't think it is the right >>> place for the pinctrl nodes there. >>> >>> Am not OK with the idea of common pinctrl nodes for STiH415 and STiH416 >>> for two reasons. >>> >>> 1> If we common up the pinctrl nodes, it will be very difficult to >>> accommodate new pinctrls layout which is not guaranteed to be in same >>> layout in future SOCs. >>> >>> 2> The retiming values in the pinctrl nodes tend to change as per SOC, >>> so it will be difficult to manage it if we common it up. >>> >>> Am sure we can come up with a dt layout which can reduce duplication, >>> but we have to be careful here not to lose the flexiblity to accommodate >>> new picntrl layouts, new retimings values based on SOC. >> Ok. What do you think of declaring the i2c nodes inside the stih41x.dtsi >> file, >> and overload them with the pinctrl and clock properties in the stih416 >> and stih415 dtsi files? > Am not very comfortable with this idea. > > As there is no guarantee that the interrupt number/memory map and the > i2c numbering will be same in future SOCs or other IPs. > > You might be already aware that the number of i2cs on each SOC are > different as example on STiH415 we have 10 SSCs and on STiH416 we have > 11 SSCs. So, At what point you decide that which devices/IPs should be > in stih41x and which should in stih415/Stih416? Yes, I know there is one more SSC on STiH416. On one hand, this could add some confusion. But on the other hand, someone who will need to activate a SSP will know which one he has to activate. > > Each i2c node will save around 5 lines if we common it up, but if the > interrupt number or map changes this difference will be negligible. > > Common up at this level and mixing un-common ones in stih415.dtsi or > stih416.dtsi will add confusion to readers as the information is split > at multiple places. I agree it will be messy if one part of the node declared at one place, and the rest at another place. > > IMO the common up idea sounds good but reduces the readability and has > no effect on final dtb size. Fair enough. Lee, are you ok with keeping it as is? Thanks, Maxime > > Thanks, > srini > > >> Regards, >> Maxime >>> >>> thanks, >>> srini >>> >>> >> >> > -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
