On 03/08/2015 08:38 PM, Mark Brown wrote:
> On Wed, Mar 04, 2015 at 02:45:00PM +0100, Javier Martinez Canillas wrote:
>
>> The thing is that _regulator_is_enabled() used to return -EINVAL if
>> the rdev didn't have an .is_enabled callback but that changed in
>> commit 9a7f6a4c6edc8 ("regulator: Assume regulators are enabled if
>> they don't report anything") and now returns 1 in that case. But
>> _regulator_enable() was not changed and is still checking for -EINVAL
>> which seems to me like a left over after the mentioned commit.
>
> You mean _do_enable(), not _enable() here. It's not really a leftover
No, I meant _enable() here. What I said is that _enable() is checking
if -EINVAL was returned by _is_enabled():
static int _regulator_enable(struct regulator_dev *rdev)
{
...
ret = _regulator_is_enabled(rdev);
if (ret == -EINVAL || ret == 0) {
if (!_regulator_can_change_status(rdev))
return -EPERM;
ret = _regulator_do_enable(rdev);
if (ret < 0)
return ret;
} else if (ret < 0) {
rdev_err(rdev, "is_enabled() failed: %d\n", ret);
return ret;
}
...
}
and my point was that it is checking because _is_enabled() used to return
-EINVAL if the regulator driver didn't provide a .is_enabled callback:
static int _regulator_is_enabled(struct regulator_dev *rdev)
{
...
if (!rdev->desc->ops->is_enabled)
return -EINVAL;
return rdev->desc->ops->is_enabled(rdev);
...
}
so, if a driver didn't provide a way to query if the regulator was enabled,
it was assumed that it was disabled. But after the mentioned commit, the
assumption was changed and now not having .is_enabled means that it's enabled:
static int _regulator_is_enabled(struct regulator_dev *rdev)
{
...
if (!rdev->desc->ops->is_enabled)
return 1;
return rdev->desc->ops->is_enabled(rdev);
...
}
So my question was if _is_enabled() returning -EINVAL should still mean
that the regulator has to be enabled or the error has to be propagated
since now -EINVAL will be returned by the driver .is_enabled callback.
> as the two operations are doing somewhat different things and the
> changes are a bit separate, _is_enabled() is reporting the current state
> while _do_enable() is making a change so it should fail if it can't do
> that.
>
Yes, I understand that.
> A better way of writing it in the _do_enable() case is that it possibly
> ought to be checking if the regulator is enabled before it does
> anything, though for uncached regulator operations that then means an
> extra I/O which isn't great. Given that I think rather than ignoring
> the missing op it should instead fall back to checking _is_enabled() -
> that way if we can read the state but not change it the right thing will
> happen. I'll do a patch, probably tomorrow.
>
Best regards,
Javier
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