On 04/24/2018 10:45 AM, Mark Brown wrote: >>> You'd need to ask Mark if he's OK with it, but a option #3 is to add a >>> patch to your series fix the regulator framework to try setting the >>> voltage if _regulator_get_voltage() fails. Presumably in >>> machine_constraints_voltage() you'd now do something like: >>> >>> int target_min, target_max; >>> int current_uV = _regulator_get_voltage(rdev); >>> if (current_uV < 0) { >>> /* Maybe this regulator's hardware can't be read and needs to be initted */ >>> _regulator_do_set_voltage( >>> rdev, rdev->constraints->min_uV, rdev->constraints->min_uV); >>> current_uV = _regulator_get_voltage(rdev); >>> } >>> if (current_uV < 0) { >>> rdev_err(rdev, >>> "failed to get the current voltage(%d)\n", >>> current_uV); >>> return current_uV; >>> } > >>> If Mark doesn't like that then I guess I'd be OK w/ initting it to 0 >>> but this needs to be documented _somewhere_ (unlike for bypass it's >>> not obvious, so you need to find someplace to put it). I'd rather not >>> hack the DT to deal with our software limitations. > >> I'm not opposed to your option #3 though it does seem a little hacky and >> tailored to the qcom_rpmh-regulator specific case. Note that I think it >> would be better to vote for min_uV to max_uV than min_uV to min_uV though. > >> Mark, what are your thoughts on the best way to handle this situation? > > I think that's probably only OK if we have a specific error code for the > regulator being limited in this way otherwise our error handling for I/O > problems involves us trying to reconfigure supplies which seems like it > would be risky. Would you be ok with -EAGAIN being used for this purpose? Thanks, David -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project -- 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