On 10/28/2016 05:12 PM, Ulf Hansson wrote: > On 25 October 2016 at 21:58, Zach Brown <zach.brown@xxxxxx> wrote: >> On some systems the sdhci capabilty registers are incorrect for one >> reason or another. >> >> The sdhci-caps-mask property specifies which bits in the registers >> are incorrect and should be turned off before using sdhci-caps to turn >> on bits. >> >> The sdhci-caps property specifies which bits should be turned on. >> >> Signed-off-by: Zach Brown <zach.brown@xxxxxx> >> --- >> Documentation/devicetree/bindings/mmc/mmc.txt | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt >> index 8a37782..1415aa0 100644 >> --- a/Documentation/devicetree/bindings/mmc/mmc.txt >> +++ b/Documentation/devicetree/bindings/mmc/mmc.txt > > The bindings in this document are common mmc DT bindings, not bindings > specific to a mmc controller. > > So unless these bindings are applicable for another controller than > sdhci, I suggest we create a new file to document these. > How about Documentation/devicetree/bindings/mmc/sdhci.txt? > >> @@ -52,6 +52,13 @@ Optional properties: >> - no-sdio: controller is limited to send sdio cmd during initialization >> - no-sd: controller is limited to send sd cmd during initialization >> - no-mmc: controller is limited to send mmc cmd during initialization >> +- sdhci-caps-mask: The sdhci capabilities registers are incorrect. This 64bit > > /s/registers/register > > This applies to some more places below as well. > >> + property corresponds to the bits in the sdhci capabilty registers. If the bit >> + is on in the mask then the bit is incorrect in the registers and should be >> + turned off. >> +- sdhci-caps: The sdhci capabilities registers are incorrect. This 64bit >> + property corresponds to the bits in the sdhci capability registers. If the >> + bit is on in the property then the bit should be on in the reigsters. > > /s/reigsters/register > >> >> *NOTE* on CD and WP polarity. To use common for all SD/MMC host controllers line >> polarity properties, we have to fix the meaning of the "normal" and "inverted" >> -- >> 2.7.4 >> > > Overall, I like this idea as it gives us good flexibility. Thus it > should avoid us to having to add any further new similar "sdhci broken > cap" DT binding. We could also decide to start deprecate some of the > existing sdhci bindings, if we think that makes sense. > > The downside is that we get a "magic" hex value in the dts. Although, > people could address this issue by providing some comments about what > the bits it means in the dts files themselves. I think it's not good about getting "magic" hex value. In my experience, it's too difficult what bits means and calculate.. Because some people who i know had already used like this.(locally..) It needs to consider this...otherwise..it should become really complex magic code. Best Regards, Jaehoon Chung > > Let's see what Rob thinks about this. > > Kind regards > Uffe > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > -- 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
