[PATCH 15/15] drm/i915/intel_dp: Add support for forcing ultrajoiner

[Ville Syrjälä]

On Wed, Sep 18, 2024 at 08:13:43PM +0530, Ankit Nautiyal wrote:
> Allow forcing ultrajoiner through debugfs.
> 
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
> Reviewed-by: Suraj Kandpal <suraj.kandpal at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_display_debugfs.c | 8 ++++++++
>  drivers/gpu/drm/i915/display/intel_dp.c              | 2 ++
>  2 files changed, 10 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> index 85742400348f..f5dcc1a4c45c 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
> @@ -1520,6 +1520,7 @@ static ssize_t i915_joiner_write(struct file *file,
>  	struct seq_file *m = file->private_data;
>  	struct intel_connector *connector = m->private;
>  	struct intel_display *display = to_intel_display(connector);
> +	struct drm_i915_private *i915 = to_i915(display->drm);
>  	int force_join_pipes = 0;
>  	int ret;
>  
> @@ -1538,6 +1539,13 @@ static ssize_t i915_joiner_write(struct file *file,
>  	case 2:
>  		connector->force_joined_pipes = force_join_pipes;
>  		break;
> +	case 4:
> +		if (HAS_ULTRAJOINER(i915)) {
> +			connector->force_joined_pipes = 4;

You assigned '... = force_join_pipes' in the other cases
so I'd do the same here instead of hardcoding the =4.

> +			break;
> +		}
> +
> +		fallthrough;
>  	default:
>  		drm_dbg(display->drm, "Ignoring Invalid num of pipes %d for force joining\n",
>  			force_join_pipes);
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 4005700ab043..be82d4485fee 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -1317,6 +1317,8 @@ int intel_dp_compute_num_pipes(struct intel_dp *intel_dp,
>  	case 1:
>  		fallthrough;
>  	case 2:
> +		fallthrough;

Unnecessary fallthrough.

> +	case 4:
>  		return connector->force_joined_pipes;
>  	default:
>  		MISSING_CASE(connector->force_joined_pipes);
> -- 
> 2.45.2

-- 
Ville Syrjälä
Intel