On Thu, 2014-07-24 at 17:23 -0700, Stephen Boyd wrote: > On 07/24/14 08:40, Linus Walleij wrote: > > On Thu, Jul 24, 2014 at 1:47 AM, Stephen Boyd <sboyd@xxxxxxxxxxxxxx> wrote: > > > >>> Please add these constants to the table of valid power-source values and use > >>> something like I did to translate them to register values - it makes the DT > >>> much more readable. > >> The DT could be similarly readable if we had a bunch of #defines for the > >> different VIN settings that resolved to the final register value for > >> that pmic. Something like PM8921_GPIO1_14_VPH, PM8921_GPIO19_36_VPH, > >> etc. There would be a lot of them, but then the driver could be really > >> simple and just jam whatever value is in the DT into the register > >> without having to bounce through a mapping table in software to figure > >> out the register value. If we did this for the functions also then I > >> believe we achieve readability without requiring a bunch of drivers for > >> each and every single pmic? > > Not sure but it sounds like you want to make the device tree a jam table, > > (know about individual register offsets, sequences etc). That has been > > throrougly NACKed in the past, because DT is not Open Firmware. > > > > The exception is pinctrl-single which is restricted to single register > > per pin use cases and is still a point of contention... > > > > I'm not proposing a jam table. I'm proposing that we make the > function/source property convenient to the driver by having the actual > function field value encoded there instead of some string that has to be > translated through a table in a driver. There's still going to be > shifting and masking of bits in the driver to put the value in the right > place in the register, but we avoid needing N number of drivers for each > pmic just to translate strings into integers (for functions) and > integers into other integers (for the power source). This sounds good to me. Drawback is that we will have custom function parsing code, but I will try and see what that looks like. Thanks, Ivan > From what I can > tell there isn't any benefit to having the function property be a string > vs. a #define number besides having a human readable string in pinctrl > debugfs. Is there some other benefit? > -- 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
