Re: [PATCH] clk: qcom: gdsc: treat optional supplies as optional

[Bjorn Andersson]

On Mon, Mar 25, 2024 at 09:58:35AM +0100, Johan Hovold wrote:
> Since commit deebc79b28d6 ("clk: qcom: gpucc-sc8280xp: Add external
> supply for GX gdsc") the GDSC supply must be treated as optional to
> avoid warnings like:
> 
> 	gpu_cc-sc8280xp 3d90000.clock-controller: supply vdd-gfx not found, using dummy regulator
> 
> on SC8280XP.
> 
> Fortunately, the driver is already prepared to handle this by checking
> that the regulator pointer is non-NULL before use.
> 
> This also avoids triggering a potential deadlock on SC8280XP even if the
> underlying issue still remains for the derivative platforms like SA8295P
> that actually use the supply.
> 
> Fixes: deebc79b28d6 ("clk: qcom: gpucc-sc8280xp: Add external supply for GX gdsc")
> Link: https://lore.kernel.org/lkml/Zf25Sv2x9WaCFuIH@xxxxxxxxxxxxxxxxxxxx/
> Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>

Thanks for fixing this, it never made it off my todo list...

Reviewed-by: Bjorn Andersson <andersson@xxxxxxxxxx>

Regards,
Bjorn

> ---
>  drivers/clk/qcom/gdsc.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/clk/qcom/gdsc.c b/drivers/clk/qcom/gdsc.c
> index e7a4068b9f39..df9618ab7eea 100644
> --- a/drivers/clk/qcom/gdsc.c
> +++ b/drivers/clk/qcom/gdsc.c
> @@ -487,9 +487,14 @@ int gdsc_register(struct gdsc_desc *desc,
>  		if (!scs[i] || !scs[i]->supply)
>  			continue;
>  
> -		scs[i]->rsupply = devm_regulator_get(dev, scs[i]->supply);
> -		if (IS_ERR(scs[i]->rsupply))
> -			return PTR_ERR(scs[i]->rsupply);
> +		scs[i]->rsupply = devm_regulator_get_optional(dev, scs[i]->supply);
> +		if (IS_ERR(scs[i]->rsupply)) {
> +			ret = PTR_ERR(scs[i]->rsupply);
> +			if (ret != -ENODEV)
> +				return ret;
> +
> +			scs[i]->rsupply = NULL;
> +		}
>  	}
>  
>  	data->num_domains = num;
> -- 
> 2.43.0
>