Re: [PATCH] pinctrl: when claiming hog, skip maps not served by same device

Tony Lindgren
2017-05-11T21:44:52Z

* Nikita Yushchenko <nikita.yoush@cogentembedded.com> [170511 13:05]:
> When pinctrl device registers, it automatically claims hogs, that is,
> maps that pinctrl device serves for itself.
>
> It is possible that in addition to SoC's pinctrl device, other pinctrl
> devices get registered. E.g. some gpio expander devies are registered
> as pinctrl devices. For such devices, pinctrl maps could be defined
> that set up SoC's pins (e.g. interrupt pin for gpio expander). Such
> a map will have target device set to gpio expander.
>
> Here is device tree snippet that causes this scenario:
>
> &i2c0 {
> sx1503@20 {
> compatible = "semtech,sx1503q";
> pinctrl-names = "default";
> pinctrl-0 = <&pinctrl_sx1503_20>;
> ...
> };
> };
> ...
> &iomuxc {
> pinctrl_sx1503_20: pinctrl-sx1503-20 {
> fsl,pins = <
> VF610_PAD_PTB1__GPIO_23 0x219d
> >;
> };
> };
>
> Such a map will have target device set to gpio expander. However is not
> a hog, it is a regular map that is claimed by core before gpio expander
> device is probed.
>
> Thus when looking for hogs, it is not enough to check that map's target
> device is set to pinctrl device being registered. Need also check that
> map's control device is also set to the same.
>
> Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> ---
> drivers/pinctrl/core.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
> index 1653cbda6a82..682ebd360030 100644
> --- a/drivers/pinctrl/core.c
> +++ b/drivers/pinctrl/core.c
> @@ -1038,6 +1038,16 @@ static struct pinctrl *create_pinctrl(struct device *dev,
> /* Map must be for this device */
> if (strcmp(map->dev_name, devname))
> continue;
> + /*
> + * If pctldev is not null, we are claiming hog for it,
> + * that means, setting that is served by pctldev by itself.
> + *
> + * Thus we must skip map that is for this device but is served
> + * by other device.
> + */
> + if (pctldev &&
> + strcmp(dev_name(pctldev->dev), map->ctrl_dev_name))
> + continue;
>
> ret = add_setting(p, pctldev, map);
> /*
> --

Maybe add a comment saying pctldev is NULL in the regular case
and only exists in the hog case?

Other than that:

Acked-by: Tony Lindgren <tony@atomide.com>