diff options
Diffstat (limited to 'include/drm/intel/display_member.h')
| -rw-r--r-- | include/drm/intel/display_member.h | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/include/drm/intel/display_member.h b/include/drm/intel/display_member.h new file mode 100644 index 000000000000..0319ea560b60 --- /dev/null +++ b/include/drm/intel/display_member.h @@ -0,0 +1,42 @@ +/* SPDX-License-Identifier: MIT */ +/* Copyright © 2025 Intel Corporation */ + +#ifndef __DRM_INTEL_DISPLAY_H__ +#define __DRM_INTEL_DISPLAY_H__ + +#include <linux/build_bug.h> +#include <linux/stddef.h> +#include <linux/stringify.h> + +#include <drm/drm_device.h> + +struct intel_display; + +/* + * A dummy device struct to define the relative offsets of drm and display + * members. With the members identically placed in struct drm_i915_private and + * struct xe_device, this allows figuring out the struct intel_display pointer + * without the definition of either driver specific structure. + */ +struct __intel_generic_device { + struct drm_device drm; + struct intel_display *display; +}; + +/** + * INTEL_DISPLAY_MEMBER_STATIC_ASSERT() - ensure correct placing of drm and display members + * @type: The struct to check + * @drm_member: Name of the struct drm_device member + * @display_member: Name of the struct intel_display * member. + * + * Use this static assert macro to ensure the struct drm_i915_private and struct + * xe_device struct drm_device and struct intel_display * members are at the + * same relative offsets. + */ +#define INTEL_DISPLAY_MEMBER_STATIC_ASSERT(type, drm_member, display_member) \ + static_assert( \ + offsetof(struct __intel_generic_device, display) - offsetof(struct __intel_generic_device, drm) == \ + offsetof(type, display_member) - offsetof(type, drm_member), \ + __stringify(type) " " __stringify(drm_member) " and " __stringify(display_member) " members at invalid offsets") + +#endif |