[Intel-gfx] [PATCH] drm/i915/dp: Add a helper function to return DP link rate index

[Jani Nikula]

On Tue, 22 Nov 2016, Manasi Navare <manasi.d.navare at intel.com> wrote:
> Common rates array is used to keep track of common rates
> supported between DP sink and source. This helper function
> returns the index of a specific link rate in this common rates
> array.
>
> This is in prep with patches for DP Link training compliance
> tests that need an index for the link rate specified by the
> test as well as for link training failure handling patches that
> require index of fallback link rate.

I'm not a fan of adding functions that are not used in prep patches.

BR,
Jani.


>
> Cc: Jani Nikula <jani.nikula at linux.intel.com>
> Cc: Daniel Vetter <daniel.vetter at intel.com>
> Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
> Signed-off-by: Manasi Navare <manasi.d.navare at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dp.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 90283ed..bf72335 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -288,6 +288,21 @@ static int intel_dp_common_rates(struct intel_dp *intel_dp,
>  			       common_rates);
>  }
>  
> +static int intel_dp_link_rate_index(struct intel_dp *intel_dp,
> +				    int *common_rates, int link_rate)
> +{
> +	int common_len;
> +	int index;
> +
> +	common_len = intel_dp_common_rates(intel_dp, common_rates);
> +	for (index = 0; index < common_len; index++) {
> +		if (link_rate == common_rates[common_len - index - 1])
> +			return common_len - index - 1;
> +	}
> +
> +	return -1;
> +}
> +
>  static enum drm_mode_status
>  intel_dp_mode_valid(struct drm_connector *connector,
>  		    struct drm_display_mode *mode)

-- 
Jani Nikula, Intel Open Source Technology Center