Re: [PATCH 3/6] drm/i915/display: add intel_display_conversion.c to hide stuff better

[Raag Jadav <raag.jadav@intel.com>]

On Thu, Oct 31, 2024 at 01:38:33PM +0200, Jani Nikula wrote:
> The __to_intel_display() generics require the definition of struct
> drm_i915_private i.e. inclusion of i915_drv.h. Add
> intel_display_conversion.c with a __i915_to_display() function to do the
> conversion without the intel_display_conversion.h having an implicit
> dependency on i915_drv.h.
> 
> The long term goal is to remove __to_intel_display() and the
> intel_display_conversion.[ch] files altoghether, and this is merely a
> transitional step to make the dependencies on i915_drv.h explicit.
> 
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> ---
>  drivers/gpu/drm/i915/Makefile                           | 1 +
>  drivers/gpu/drm/i915/display/intel_display_conversion.c | 9 +++++++++
>  drivers/gpu/drm/i915/display/intel_display_conversion.h | 9 +++++++--
>  drivers/gpu/drm/xe/Makefile                             | 1 +
>  4 files changed, 18 insertions(+), 2 deletions(-)
>  create mode 100644 drivers/gpu/drm/i915/display/intel_display_conversion.c
> 
> diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
> index ac47d7e988fc..43686d843ef7 100644
> --- a/drivers/gpu/drm/i915/Makefile
> +++ b/drivers/gpu/drm/i915/Makefile
> @@ -237,6 +237,7 @@ i915-y += \
>  	display/intel_crtc_state_dump.o \
>  	display/intel_cursor.o \
>  	display/intel_display.o \
> +	display/intel_display_conversion.o \
>  	display/intel_display_driver.o \
>  	display/intel_display_irq.o \
>  	display/intel_display_params.o \
> diff --git a/drivers/gpu/drm/i915/display/intel_display_conversion.c b/drivers/gpu/drm/i915/display/intel_display_conversion.c
> new file mode 100644
> index 000000000000..bdd947f5ccd8
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/display/intel_display_conversion.c
> @@ -0,0 +1,9 @@
> +// SPDX-License-Identifier: MIT
> +/* Copyright © 2024 Intel Corporation */
> +
> +#include "i915_drv.h"
> +
> +struct intel_display *__i915_to_display(struct drm_i915_private *i915)
> +{
> +	return &i915->display;
> +}
> diff --git a/drivers/gpu/drm/i915/display/intel_display_conversion.h b/drivers/gpu/drm/i915/display/intel_display_conversion.h
> index ad8545c8055d..790d0be698dc 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_conversion.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_conversion.h
> @@ -8,14 +8,19 @@
>  #ifndef __INTEL_DISPLAY_CONVERSION__
>  #define __INTEL_DISPLAY_CONVERSION__
>  
> +struct drm_i915_private;
> +struct intel_display;
> +
> +struct intel_display *__i915_to_display(struct drm_i915_private *i915);
> +
>  /*
>   * Transitional macro to optionally convert struct drm_i915_private * to struct
>   * intel_display *, also accepting the latter.
>   */
>  #define __to_intel_display(p)						\
>  	_Generic(p,							\
> -		 const struct drm_i915_private *: (&((const struct drm_i915_private *)(p))->display), \
> -		 struct drm_i915_private *: (&((struct drm_i915_private *)(p))->display), \
> +		 const struct drm_i915_private *: __i915_to_display((struct drm_i915_private *)(p)), \
> +		 struct drm_i915_private *: __i915_to_display((struct drm_i915_private *)(p)), \
>  		 const struct intel_display *: (p),			\
>  		 struct intel_display *: (p))

Perhaps,

#define TYPE_ENTRY(type, x)	\
	const type: x,		\
	type: x

May snip the duplication.

Raag