On Tue, Jun 9, 2015 at 12:53 AM, Dov Levenglick <dovl@xxxxxxxxxxxxxx> wrote: >> On Sun, Jun 7, 2015 at 10:32 AM, <ygardi@xxxxxxxxxxxxxx> wrote: >>>> 2015-06-05 5:53 GMT+09:00 <ygardi@xxxxxxxxxxxxxx>: [...] >>> If ufshcd-pltfrm driver is loaded before ufs-qcom, (what actually >>> happens >>> always), then the calling to of_platform_populate() which is added, >>> guarantees that ufs-qcom probe will be called and finish, before >>> ufshcd_pltfrm probe continues. >>> so ufs_variant device is always there, and ready. >>> I think it means we are safe - since either way, we make sure ufs-qcom >>> probe will be called and finish before dealing with ufs_variant device >>> in >>> ufshcd_pltfrm probe. >> >> This is due to the fact that you have 2 platform drivers. You should >> only have 1 (and 1 node). If you really think you need 2, then you >> should do like many other common *HCIs do and make the base UFS driver >> a set of library functions that drivers can use or call. Look at EHCI, >> AHCI, SDHCI, etc. for inspiration. > > Hi Rob, > We did look at SDHCI and decided to go with this design due to its > simplicity and lack of library functions. Yaniv described the proper flow > of probing and, as we understand things, it is guaranteed to work as > designed. > > Furthermore, the design of having a subcore in the dts is used in the > Linux kernel. Please have a look at drivers/usb/dwc3 where - as an example > - both dwc3-msm and dwc3-exynox invoke the probing function in core.c > (i.e. the shared underlying Synopsys USB dwc3 core) by calling > of_platform_populate(). That binding has the same problem. Please don't propagate that. There is no point in a sub-node in this case. > Do you see a benefit in the SDHCi implementation? Yes, it does not let the kernel driver design dictate the hardware description. Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
