Re: [PATCH] drm/amdgpu: fix build for CONFIG_DRM_FBDEV_EMULATION=n

[Thomas Zimmermann <tzimmermann@suse.de>]

Hi

Am 24.04.26 um 20:48 schrieb Yury Norov:
> The merge-commit 02e778f12359 ("Merge tag 'amd-drm-next-7.1-2026-03-12' of
> https://gitlab.freedesktop.org/agd5f/linux into drm-next") removes stubs
> for drm_fb_helper_xxx() functions, so the buld gets broken if
> DRM_FBDEV_EMULATION is not set.
>
> ‘drm_fb_helper_gem_is_fb’; did you mean ‘drm_fb_helper_from_client’? [-Wimplicit-function-declaration]
>   1777 |                 if (!drm_fb_helper_gem_is_fb(dev->fb_helper, fb->obj[0])) {
>        |                      ^~~~~~~~~~~~~~~~~~~~~~~
>        |                      drm_fb_helper_from_client
>
> Restore the stubs.
> Fixes: 02e778f12359 ("Merge tag 'amd-drm-next-7.1-2026-03-12' of https://gitlab.freedesktop.org/agd5f/linux into drm-next")
> Signed-off-by: Yury Norov <ynorov@nvidia.com>
> ---
>   include/drm/drm_fb_helper.h | 111 ++++++++++++++++++++++++++++++++++++
>   1 file changed, 111 insertions(+)
>
> diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h
> index bf391903443d..ca214b5c0283 100644
> --- a/include/drm/drm_fb_helper.h
> +++ b/include/drm/drm_fb_helper.h
> @@ -273,6 +273,117 @@ int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
>   int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper);
>   bool drm_fb_helper_gem_is_fb(const struct drm_fb_helper *fb_helper,
>   			     const struct drm_gem_object *obj);
> +#else
> +static inline bool drm_fb_helper_gem_is_fb(const struct drm_fb_helper *fb_helper,
> +					   const struct drm_gem_object *obj)
> +{
> +	return false;
> +}

Only this helper is required. The others have been removed.

Best regards
Thomas

> +
> +static inline void drm_fb_helper_prepare(struct drm_device *dev,
> +					 struct drm_fb_helper *helper,
> +					 unsigned int preferred_bpp,
> +					 const struct drm_fb_helper_funcs *funcs)
> +{
> +}
> +
> +static inline void drm_fb_helper_unprepare(struct drm_fb_helper *fb_helper)
> +{
> +}
> +
> +static inline int drm_fb_helper_init(struct drm_device *dev,
> +		       struct drm_fb_helper *helper)
> +{
> +	/* So drivers can use it to free the struct */
> +	helper->dev = dev;
> +	dev->fb_helper = helper;
> +
> +	return 0;
> +}
> +
> +static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
> +{
> +	if (helper && helper->dev)
> +		helper->dev->fb_helper = NULL;
> +}
> +
> +static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
> +{
> +	return 0;
> +}
> +
> +static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
> +					    struct fb_info *info)
> +{
> +	return 0;
> +}
> +
> +static inline int drm_fb_helper_set_par(struct fb_info *info)
> +{
> +	return 0;
> +}
> +
> +static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
> +					  struct fb_info *info)
> +{
> +	return 0;
> +}
> +
> +static inline int
> +drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
> +{
> +	return 0;
> +}
> +
> +static inline void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper)
> +{
> +}
> +
> +static inline void
> +drm_fb_helper_fill_info(struct fb_info *info,
> +			struct drm_fb_helper *fb_helper,
> +			struct drm_fb_helper_surface_size *sizes)
> +{
> +}
> +
> +static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
> +					struct fb_info *info)
> +{
> +	return 0;
> +}
> +
> +static inline int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
> +				      unsigned long arg)
> +{
> +	return 0;
> +}
> +
> +#ifdef CONFIG_FB_DEFERRED_IO
> +static inline void drm_fb_helper_deferred_io(struct fb_info *info,
> +					     struct list_head *pagelist)
> +{
> +}
> +#endif
> +
> +static inline void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper,
> +					     bool suspend)
> +{
> +}
> +
> +static inline void
> +drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, bool suspend)
> +{
> +}
> +
> +static inline int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
> +{
> +	return 0;
> +}
> +
> +static inline int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper)
> +{
> +	return 0;
> +}
>   #endif
>   
>   #endif

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)