Re: [PATCH 1/2] drm/i915/display: add intel_dig_port_alloc()

[Dibin Moolakadan Subrahmanian <dibin.moolakadan.subrahmanian@intel.com>]

On 29-07-2025 16:47, Jani Nikula wrote:
> Add a common allocator function for struct intel_digital_port, with some
> member default initialization to deduplicate them from everywhere
> else. This is similar to intel_connector_alloc().
>
> At least for now, place this in intel_encoder.[ch]. We don't have a
> dedicated file for dig port stuff, and there wouldn't be much to add
> there anyway. A digital port is a sort of subclass of encoder, so the
> location isn't far off the mark.
>
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Looks good to me.
Reviewed-by: Dibin Moolakadan Subrahmanian <dibin.moolakadan.subrahmanian@intel.com>

> ---
>   drivers/gpu/drm/i915/display/g4x_dp.c        |  7 +------
>   drivers/gpu/drm/i915/display/g4x_hdmi.c      |  9 ++-------
>   drivers/gpu/drm/i915/display/intel_ddi.c     |  8 +-------
>   drivers/gpu/drm/i915/display/intel_encoder.c | 18 ++++++++++++++++++
>   drivers/gpu/drm/i915/display/intel_encoder.h |  3 +++
>   5 files changed, 25 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/g4x_dp.c b/drivers/gpu/drm/i915/display/g4x_dp.c
> index 846dbd8ae931..aa159f9ce12f 100644
> --- a/drivers/gpu/drm/i915/display/g4x_dp.c
> +++ b/drivers/gpu/drm/i915/display/g4x_dp.c
> @@ -1300,12 +1300,10 @@ bool g4x_dp_init(struct intel_display *display,
>   		drm_dbg_kms(display->drm, "No VBT child device for DP-%c\n",
>   			    port_name(port));
>   
> -	dig_port = kzalloc(sizeof(*dig_port), GFP_KERNEL);
> +	dig_port = intel_dig_port_alloc();
>   	if (!dig_port)
>   		return false;
>   
> -	dig_port->aux_ch = AUX_CH_NONE;
> -
>   	intel_connector = intel_connector_alloc();
>   	if (!intel_connector)
>   		goto err_connector_alloc;
> @@ -1315,8 +1313,6 @@ bool g4x_dp_init(struct intel_display *display,
>   
>   	intel_encoder->devdata = devdata;
>   
> -	mutex_init(&dig_port->hdcp.mutex);
> -
>   	if (drm_encoder_init(display->drm, &intel_encoder->base,
>   			     &intel_dp_enc_funcs, DRM_MODE_ENCODER_TMDS,
>   			     "DP %c", port_name(port)))
> @@ -1386,7 +1382,6 @@ bool g4x_dp_init(struct intel_display *display,
>   	}
>   
>   	dig_port->dp.output_reg = output_reg;
> -	dig_port->max_lanes = 4;
>   
>   	intel_encoder->type = INTEL_OUTPUT_DP;
>   	intel_encoder->power_domain = intel_display_power_ddi_lanes_domain(display, port);
> diff --git a/drivers/gpu/drm/i915/display/g4x_hdmi.c b/drivers/gpu/drm/i915/display/g4x_hdmi.c
> index 2610f5702fb9..108ebd97f9e4 100644
> --- a/drivers/gpu/drm/i915/display/g4x_hdmi.c
> +++ b/drivers/gpu/drm/i915/display/g4x_hdmi.c
> @@ -19,6 +19,7 @@
>   #include "intel_display_types.h"
>   #include "intel_dp_aux.h"
>   #include "intel_dpio_phy.h"
> +#include "intel_encoder.h"
>   #include "intel_fdi.h"
>   #include "intel_fifo_underrun.h"
>   #include "intel_hdmi.h"
> @@ -690,12 +691,10 @@ bool g4x_hdmi_init(struct intel_display *display,
>   		drm_dbg_kms(display->drm, "No VBT child device for HDMI-%c\n",
>   			    port_name(port));
>   
> -	dig_port = kzalloc(sizeof(*dig_port), GFP_KERNEL);
> +	dig_port = intel_dig_port_alloc();
>   	if (!dig_port)
>   		return false;
>   
> -	dig_port->aux_ch = AUX_CH_NONE;
> -
>   	intel_connector = intel_connector_alloc();
>   	if (!intel_connector)
>   		goto err_connector_alloc;
> @@ -704,8 +703,6 @@ bool g4x_hdmi_init(struct intel_display *display,
>   
>   	intel_encoder->devdata = devdata;
>   
> -	mutex_init(&dig_port->hdcp.mutex);
> -
>   	if (drm_encoder_init(display->drm, &intel_encoder->base,
>   			     &intel_hdmi_enc_funcs, DRM_MODE_ENCODER_TMDS,
>   			     "HDMI %c", port_name(port)))
> @@ -767,8 +764,6 @@ bool g4x_hdmi_init(struct intel_display *display,
>   		intel_encoder->cloneable |= BIT(INTEL_OUTPUT_HDMI);
>   
>   	dig_port->hdmi.hdmi_reg = hdmi_reg;
> -	dig_port->dp.output_reg = INVALID_MMIO_REG;
> -	dig_port->max_lanes = 4;
>   
>   	intel_infoframe_init(dig_port);
>   
> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> index 0405396c7750..403249345f12 100644
> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> @@ -5148,12 +5148,10 @@ void intel_ddi_init(struct intel_display *display,
>   			    phy_name(phy));
>   	}
>   
> -	dig_port = kzalloc(sizeof(*dig_port), GFP_KERNEL);
> +	dig_port = intel_dig_port_alloc();
>   	if (!dig_port)
>   		return;
>   
> -	dig_port->aux_ch = AUX_CH_NONE;
> -
>   	encoder = &dig_port->base;
>   	encoder->devdata = devdata;
>   
> @@ -5191,9 +5189,6 @@ void intel_ddi_init(struct intel_display *display,
>   
>   	intel_encoder_link_check_init(encoder, intel_ddi_link_check);
>   
> -	mutex_init(&dig_port->hdcp.mutex);
> -	dig_port->hdcp.num_streams = 0;
> -
>   	encoder->hotplug = intel_ddi_hotplug;
>   	encoder->compute_output_type = intel_ddi_compute_output_type;
>   	encoder->compute_config = intel_ddi_compute_config;
> @@ -5331,7 +5326,6 @@ void intel_ddi_init(struct intel_display *display,
>   
>   	dig_port->ddi_a_4_lanes = DISPLAY_VER(display) < 11 && ddi_buf_ctl & DDI_A_4_LANES;
>   
> -	dig_port->dp.output_reg = INVALID_MMIO_REG;
>   	dig_port->max_lanes = intel_ddi_max_lanes(dig_port);
>   
>   	if (need_aux_ch(encoder, init_dp)) {
> diff --git a/drivers/gpu/drm/i915/display/intel_encoder.c b/drivers/gpu/drm/i915/display/intel_encoder.c
> index 0b7bd26f4339..f9ce81320d68 100644
> --- a/drivers/gpu/drm/i915/display/intel_encoder.c
> +++ b/drivers/gpu/drm/i915/display/intel_encoder.c
> @@ -80,3 +80,21 @@ void intel_encoder_shutdown_all(struct intel_display *display)
>   		if (encoder->shutdown_complete)
>   			encoder->shutdown_complete(encoder);
>   }
> +
> +struct intel_digital_port *intel_dig_port_alloc(void)
> +{
> +	struct intel_digital_port *dig_port;
> +
> +	dig_port = kzalloc(sizeof(*dig_port), GFP_KERNEL);
> +	if (!dig_port)
> +		return NULL;
> +
> +	dig_port->hdmi.hdmi_reg = INVALID_MMIO_REG;
> +	dig_port->dp.output_reg = INVALID_MMIO_REG;
> +	dig_port->aux_ch = AUX_CH_NONE;
> +	dig_port->max_lanes = 4;
> +
> +	mutex_init(&dig_port->hdcp.mutex);
> +
> +	return dig_port;
> +}
> diff --git a/drivers/gpu/drm/i915/display/intel_encoder.h b/drivers/gpu/drm/i915/display/intel_encoder.h
> index 3fa5589f0b1c..65a9c521f8a6 100644
> --- a/drivers/gpu/drm/i915/display/intel_encoder.h
> +++ b/drivers/gpu/drm/i915/display/intel_encoder.h
> @@ -6,6 +6,7 @@
>   #ifndef __INTEL_ENCODER_H__
>   #define __INTEL_ENCODER_H__
>   
> +struct intel_digital_port;
>   struct intel_display;
>   struct intel_encoder;
>   
> @@ -17,4 +18,6 @@ void intel_encoder_link_check_flush_work(struct intel_encoder *encoder);
>   void intel_encoder_suspend_all(struct intel_display *display);
>   void intel_encoder_shutdown_all(struct intel_display *display);
>   
> +struct intel_digital_port *intel_dig_port_alloc(void);
> +
>   #endif /* __INTEL_ENCODER_H__ */