Re: [PATCH v1 30/30] drm/i915/dp: return -EINVAL on failure

[Imre Deak <imre.deak@intel.com>]

On Wed, Jun 24, 2026 at 12:46:19AM +0200, Michał Grzelak wrote:
> Both intel_dp_rate_index() and intel_dp_link_config_index() in case of
> failure return -1 which equates to -EPERM. Return -EINVAL instead since
> each caller checks for negative error code.
> 
> Cc: Jani Nikula <jani.nikula@intel.com>
> Signed-off-by: Michał Grzelak <michal.grzelak@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c           | 2 +-
>  drivers/gpu/drm/i915/display/intel_dp_link_caps.c | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 66346b74b2c04..1c0b85ac27ad5 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -666,7 +666,7 @@ int intel_dp_rate_index(const int *rates, int len, int rate)
>  		if (rate == rates[i])
>  			return i;
>  
> -	return -1;
> +	return -EINVAL;

I'm not sure about these changes. Both of these functions can fail in
one way and returning an invalid index in that case looks ok to me.

>  }
>  
>  static void intel_dp_get_common_rates(struct intel_dp *intel_dp,
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_caps.c b/drivers/gpu/drm/i915/display/intel_dp_link_caps.c
> index 1c34ba6c49c35..241809e6a9cb2 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_link_caps.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_link_caps.c
> @@ -347,7 +347,7 @@ int intel_dp_link_config_index(struct intel_dp_link_caps *link_caps,
>  			return i;
>  	}
>  
> -	return -1;
> +	return -EINVAL;
>  }
>  
>  /**
> -- 
> 2.45.2
>