Re: lm90 driver no longer working on PCs in 3.13

From: Jean Delvare
Date: Sun Jan 26 2014 - 15:49:53 EST


On Sun, 26 Jan 2014 12:44:38 -0800, Guenter Roeck wrote:
> On 01/26/2014 12:13 PM, Jean Delvare wrote:
> The regulator code changed with 3.13; the dummy regulator no longer exists,
> and the functionality it provided is supposed to be handled automatically.
> But that only really works on devicetree based systems and otherwise returns
> -EPROBE_DEFER as mentioned above.
>
> Maybe there is some configuration option, or maybe something needs to be
> configured from user space. I found neither.

Neither would be acceptable to my eyes anyway. Things worked out of the
box before, they should keep working out of the box.

> In the first case, we should create
> a dependency for the LM90 driver; in the latter case, we would have to make sure
> that it is well documented (I'd grumble on that, though - it would result in
> never ending trouble for us, having to repeatedly explain how this is now
> supposed to work).
>
> Another possible fix would be to have the regulator core return -ENODEV
> instead of -EPROBE_DEFER on non-dt systems. No idea if this would be acceptable
> or even feasible.

Well, either the regulator subsystem gets fixed (or provides a suitable
API for drivers like lm90 and we update the lm90 driver to use it), or
I'll just revert the problematic commit for now. This is a severe
regression, we just can't leave things that way.

--
Jean Delvare
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