On Fri, Jan 30, 2015 at 5:20 PM, Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxx> wrote: > On Fri 30 Jan 02:27 PST 2015, Stanimir Varbanov wrote: > >> + case PIN_CONFIG_INPUT_ENABLE: >> + /* Pin is output */ >> + if (arg) >> + return -EINVAL; >> + arg = 1; >> + break; > > My idea of this function is to query if we have the specific option > enabled, so I don't like the fact that we're returning an error here, we > should just return 0 with arg 0 (or something like that). > > However, that would not give the results we expect and your patch is > "correct". > > Linus, conf_items in pinconf_generic_dump_one() seems to represent > boolean properties of the pins. Returning 0 from pin_config_*_get() > should in my view then be treated as it not being active. > > Is this in line with your view and should we modify > pinconf_generic_dump_one() to continue for these values if the getter > returns 0? > > If not, at least all the bias properties here should return -EINVAL as > well. (which I think is wrong) Well currently the semantics are: - ENOTSUPP = this property is not even supported - EINVAL = this value exists but can not be determined It has this form primarily to serve the non-boolean properties. For example pull-up can return -EINVAL if pull-up is supported but pull-down is currently active, so it cannot say what resistance it is pulled up with, as it is "infinite" (NAN, thus translated -EINVAL). It just folds over to the boolean props doing things in the same way to simplify things... -EINVAL just means "false". If we should return 1/0 from boolean props we need to handle them as a special case in the pinconf-generic. code, by extending the struct pinconf_generic_params, which is possible of course. Further: as of now pinconf_generic_dump_one() doesn't print anything for inactive pulls etc return -EINVAL, but maybe it should? It was just handy on some system to only see the stuff that was really active, not to get a list of stuff that was not active as well. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
