Quoting Doug Anderson (2018-06-19 14:38:57) > On Tue, Jun 19, 2018 at 2:18 PM, Stephen Boyd <swboyd@xxxxxxxxxxxx> wrote: > > Quoting Doug Anderson (2018-06-18 16:54:49) > >> > >> Is there a reason why you'd want to return 0 instead of some sort of > >> error code? Wouldn't you want to know that this pin can't be a GPIO? > > > > On ACPI there aren't any functions and thus all pins are GPIO mode and > > only GPIO mode if they're used as GPIOs. At least that's my > > understanding of how the ACPI version of this driver works. > > OK. I have no understanding of how the ACPI version of this driver > works, so your understanding is much more likely to be right than > mine. I guess this is just "pinctrl-qdf2xxx.c"? > Yes that's the single ACPI driver. > > >> Another non-ACPI example is sdc2 on sdm845 and it seems like you'd > >> want to know if someone tried to set one of those as a GPIO. > >> > >> ...oh, but I guess ufs_reset also has no funcs but it still probably > >> wants to use the GPIO framework to write something. Hrmmm... Maybe > >> check if either in_bit or out_bit is not -1? > > > > ufs_reset and sdc2 aren't in the GPIO chip's numberspace so I don't > > think we need to care? At least I can't convince myself that those pins > > would eventually call into the this function. We could check if offset > > is greater than ngpios for the chip but that seems useless if higher > > layers are handling this already. > > Ah, I see what you mean. These pins do have numbers in the code: > > PINCTRL_PIN(150, "SDC2_CLK"), > PINCTRL_PIN(151, "SDC2_CMD"), > PINCTRL_PIN(152, "SDC2_DATA"), > PINCTRL_PIN(153, "UFS_RESET"), > > ...but those are effectively made up numbers and they are all past the > "ngpios" (150). ...and the higher level code seems to be already > checking that. Right. Hopefully that saves us from this trouble. > > > OK, thought I've already proven my cluelessness about this driver, > FWIW this patch makes sense to me now so FWIW: > > Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx> > Thanks! -- 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
