Re: [PATCH v2 4/5] gnss: sirf: add a separate supply for a lna

From: Johan Hovold
Date: Thu Jan 10 2019 - 07:25:15 EST


On Sun, Dec 09, 2018 at 08:51:49PM +0100, Andreas Kemnade wrote:
> Devices might have a separate lna between antenna output of the gps
> chip and the antenna which might have a separate supply.

Fix the s/antenna output/antenna input/ as per Nikolaus comment.

> Signed-off-by: Andreas Kemnade <andreas@xxxxxxxxxxxx>
> ---
> Changes in v2:
> - handle lna also if there is no on-off gpio
> - rebase on changed 2/5
>
> drivers/gnss/sirf.c | 26 ++++++++++++++++++++++----
> 1 file changed, 22 insertions(+), 4 deletions(-)

You also need to update the binding docs. As already discussed I think
adding this to the generic binding is appropriate (even if only sirf
implements it initially).

> diff --git a/drivers/gnss/sirf.c b/drivers/gnss/sirf.c
> index c64369494afb..d339e8ef2508 100644
> --- a/drivers/gnss/sirf.c
> +++ b/drivers/gnss/sirf.c
> @@ -36,6 +36,7 @@ struct sirf_data {
> struct serdev_device *serdev;
> speed_t speed;
> struct regulator *vcc;
> + struct regulator *lna;
> struct gpio_desc *on_off;
> struct gpio_desc *wakeup;
> int irq;
> @@ -282,21 +283,32 @@ static int sirf_set_active(struct sirf_data *data, bool active)
> static int sirf_runtime_suspend(struct device *dev)
> {
> struct sirf_data *data = dev_get_drvdata(dev);
> + int ret = 0;

No need to initialise.

> if (!data->on_off)

Perhaps invert this test now too.

> - return regulator_disable(data->vcc);
> + ret = regulator_disable(data->vcc);
> + else
> + ret = sirf_set_active(data, false);
>
> - return sirf_set_active(data, false);
> + if (ret)
> + return ret;
> +
> + return regulator_disable(data->lna);

You need to undo the above if this call fails.

> }
>
> static int sirf_runtime_resume(struct device *dev)
> {
> struct sirf_data *data = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = regulator_enable(data->lna);
> + if (ret)
> + return ret;
>
> if (!data->on_off)
> return regulator_enable(data->vcc);
> -
> - return sirf_set_active(data, true);
> + else
> + return sirf_set_active(data, true);

You must undo the changes here too on errors since we call this function
directly from probe in one case.

> }
>
> static int __maybe_unused sirf_suspend(struct device *dev)
> @@ -384,6 +396,12 @@ static int sirf_probe(struct serdev_device *serdev)
> goto err_put_device;
> }
>
> + data->lna = devm_regulator_get(dev, "lna");
> + if (IS_ERR(data->lna)) {
> + ret = PTR_ERR(data->lna);
> + goto err_put_device;
> + }
> +
> data->on_off = devm_gpiod_get_optional(dev, "sirf,onoff",
> GPIOD_OUT_LOW);
> if (IS_ERR(data->on_off))

Johan