Re: [PATCH 4/6] regulator: lp872x: Add enable GPIO pin support

From: Paul Kocialkowski
Date: Thu Dec 24 2015 - 13:13:14 EST


Le mercredi 23 dÃcembre 2015 Ã 11:56 +0000, Mark Brown a Ãcrit :
> On Wed, Dec 23, 2015 at 11:58:37AM +0100, Paul Kocialkowski wrote:
>
> > + gpio = lp->pdata->enable_gpio;
> > + if (!gpio_is_valid(gpio))
> > + return 0;
> > +
> > + /* Always set enable GPIO high. */
> > + ret = devm_gpio_request_one(lp->dev, gpio, GPIOF_OUT_INIT_HIGH, "LP872X EN");
> > + if (ret) {
> > + dev_err(lp->dev, "gpio request err: %d\n", ret);
> > + return ret;
> > + }
>
> This isn't really adding support for the enable GPIO as the changelog
> suggests, it's requesting but not managing the GPIO. Since there is
> core support for manging enable GPIOs this seems especially silly,
> please tell the core about the GPIO and then it will work at runtime
> too.

It looks like the core bindings for GPIO can only be used instead of the
rdev->desc->ops->enable callback, not jointly, which doesn't fit my use
case, where both the GPIO and register write have to be used to enable
regulators.

I think it would be worth making it possible to use both in core, since
that situation is probably shared with other regulators. I suggest the
following diff (that would be split into a separate patch in v2 of this
series):

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index e92f344..dd0674f 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1963,7 +1963,6 @@ static int regulator_ena_gpio_ctrl(struct
regulator_dev *rdev, bool enable)
if (pin->enable_count == 0)
gpiod_set_value_cansleep(pin->gpiod,
!pin->ena_gpio_invert);
-
pin->enable_count++;
} else {
if (pin->enable_count > 1) {
@@ -2063,6 +2062,14 @@ static int _regulator_do_enable(struct
regulator_dev *rdev)
}
}

+ if (rdev->desc->ops->enable) {
+ ret = rdev->desc->ops->enable(rdev);
+ if (ret < 0)
+ return ret;
+ } else if (!rdev->ena_pin) {
+ return -EINVAL;
+ }
+
if (rdev->ena_pin) {
if (!rdev->ena_gpio_state) {
ret = regulator_ena_gpio_ctrl(rdev, true);
@@ -2070,10 +2077,6 @@ static int _regulator_do_enable(struct
regulator_dev *rdev)
return ret;
rdev->ena_gpio_state = 1;
}
- } else if (rdev->desc->ops->enable) {
- ret = rdev->desc->ops->enable(rdev);
- if (ret < 0)
- return ret;
} else {
return -EINVAL;
}

Attachment: signature.asc
Description: This is a digitally signed message part