Hi, On Mon, Sep 24, 2018 at 11:23 AM Trent Piepho <tpiepho@xxxxxxxxxx> wrote: > > On Mon, 2018-09-24 at 10:13 -0700, Doug Anderson wrote: > > IIUC previous suggestions about just naming it based on the first SoC > > was due to the difficulty of coming up with a good generic name to > > give something. For instance you definitely wouldn't want to name it > > "qcom-qspi-sdm8xx" because you have no idea what future SoCs will be > > numbered. > > And the hypothetical sdm899 might use a non-compatible device that uses > a different driver, and that really makes "qcom-qspi-sdm8xx" look dumb. > > > > > In the case here calling it "qcom,qspi-v1" is better than that and if > > Rob gives the thumbs up then I won't object to it. In general though > > looking at other device tree bindings this doesn't seem like a thing > > commonly done. Perhaps if we decide it's useful here we should start > > suggesting it everywhere... > > It would help if the programming model or IP core name or whatever this > is using was mentioned in the public reference manual for the SoC. > Then is a lot more clear that a number of different SoCs all have the > same quad spi controller inside them. > > Usually it's not like that. The RMs just say, "it's got a SPI master > with these registers." What SoCs use the same IP module, which > different? When did they make a new version? The silicon vendors > don't tell you this. So any name we make up for the IP module likely > doesn't match reality. Note that Rob did recently give a positive review to a similar binding. See: https://lore.kernel.org/patchwork/patch/979432/ Specifically the text from that binding was: + Qcom SoCs must contain, as below, SoC-specific compatibles + along with "qcom,smmu-v2": + "qcom,msm8996-smmu-v2", "qcom,smmu-v2", + "qcom,sdm845-smmu-v2", "qcom,smmu-v2". Given Rob's positive review there, it seems like it would be fine to do: "qcom,sdm845-qspi", "qcom,qspi-v1". NOTE: In our case we don't need the "-v1" in SoC-specific case since there's only one Quad SPI driver there. As I understand it the reason we needed the -v2 in the SoC-specific case for the SMMU was that there are two totally different SMMUs in SDM845. You can see history in the v15 patch <https://lore.kernel.org/patchwork/patch/977888/> -Doug
