Re: [PATCH v3 3/4] regulator: core: Parse coupled regulators properties

From: Maciej Purski
Date: Thu Dec 21 2017 - 05:08:36 EST

On 12/12/2017 12:35 PM, Mark Brown wrote:
On Thu, Dec 07, 2017 at 10:46:14AM +0100, Maciej Purski wrote:
+ mutex_lock(&regulator_list_mutex);
+ regulator_resolve_coupling(rdev);
+ mutex_unlock(&regulator_list_mutex);

I'd really expect us to be failing to probe if we run into an error.
Otherwise we could end up doing bad things to the hardware at runtime
later on, or confusing ourselves and crashing with partially set up

We cannot fail to probe if some of the regulators are not registered successfully, as depending on the probing sequence, there will be some regulators, which won't be available when registering others. We can fail when resolving coupling if we encounter other errors such as max_spread not provided or disability to set voltage. Maybe that is what you meant.

It's also not 100% clear to me how we handle the case
where only some of the coupled regulators have probed.

I have two ideas how to handle it. We can prohibit setting the voltage and always fail on attempt to set voltage of a coupled regulator. Or we can just ignore it and set voltage of the regulator without checking the unregistered ones.