Re: [Intel-gfx] [PATCH v3 4/6] drm/i915/opregion: Cond dgfx opregion func registration

[Jani Nikula]

On Sun, 20 Feb 2022, Anshuman Gupta <anshuman.gu...@intel.com> wrote:
> DGFX ASLS and OPROM OpRegion are only supported on the GFX Cards,
> which supports Display Engine. Register opregion function accordingly
> using the HAS_DISPLAY(). And early return intel_opregion_setup()
> if no opregion func to avoid NULL pointer oops.
>
> v2:
> - Change the commit log.
>
> Cc: Badal Nilawar <badal.nila...@intel.com>
> Cc: Jani Nikula <jani.nik...@intel.com>
> Cc: Uma Shankar <uma.shan...@intel.com>
> Signed-off-by: Anshuman Gupta <anshuman.gu...@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_opregion.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_opregion.c 
> b/drivers/gpu/drm/i915/display/intel_opregion.c
> index eca2d3a4f72b..562161a929d6 100644
> --- a/drivers/gpu/drm/i915/display/intel_opregion.c
> +++ b/drivers/gpu/drm/i915/display/intel_opregion.c
> @@ -894,6 +894,9 @@ static int intel_opregion_setup(struct drm_i915_private 
> *dev_priv)
>       BUILD_BUG_ON(sizeof(struct opregion_asle) != 0x100);
>       BUILD_BUG_ON(sizeof(struct opregion_asle_ext) != 0x400);
>  
> +     if (!opregion->opregion_func)
> +             return 0;
> +
>       INIT_WORK(&opregion->asle_work, asle_work);
>  
>       base = opregion->opregion_func->alloc_opregion(dev_priv);
> @@ -1348,9 +1351,9 @@ int intel_opregion_init(struct drm_i915_private *i915)
>  {
>       struct intel_opregion *opregion = &i915->opregion;
>  
> -     if (IS_DGFX(i915))
> +     if (IS_DGFX(i915) && HAS_DISPLAY(i915))
>               opregion->opregion_func = &dgfx_opregion_func;
> -     else
> +     else if (!IS_DGFX(i915))
>               opregion->opregion_func = &igfx_opregion_func;

IOW, and IMO much clearer:

        if (dgfx) {
                if (has_dislay)
                        ...
        } else {
                ...
        }

>  
>       return intel_opregion_setup(i915);

-- 
Jani Nikula, Intel Open Source Graphics Center