Re: [PATCH] regulator: fp9931: Fix error handling for optional regulator

[Andreas Kemnade <andreas@kemnade.info>]

On Thu, 12 Mar 2026 12:01:48 +0800
Robby Cai <robby.cai@nxp.com> wrote:

> If "vin" reg does not exist in the device tree, the regulator framework
> returns -ENODEV, which is normal for an optional supply. But the current
> code treats -ENODEV as a fatal error, causing the driver probe to fail.
> This patch fixes that by handling -ENODEV correctly for optional regulator.
> 
> Fixes: 12d821bd13d4 ("regulator: Add FP9931/JD9930 driver")
> Signed-off-by: Robby Cai <robby.cai@nxp.com>
> ---
>  drivers/regulator/fp9931.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/regulator/fp9931.c b/drivers/regulator/fp9931.c
> index 7fbcc6327cc63..fa7f32adfb666 100644
> --- a/drivers/regulator/fp9931.c
> +++ b/drivers/regulator/fp9931.c
> @@ -448,9 +448,13 @@ static int fp9931_probe(struct i2c_client *client)
>  				     "failed to allocate regmap!\n");
>  
>  	data->vin_reg = devm_regulator_get_optional(&client->dev, "vin");

looking at that thing again. I think I have abused the optional api.
Of course this chip needs a supply. It may be hardwired so something
not switchable. But that needs to be wired to something... So I think
rather the _optional is wrong here.

Regards,
Andreas