drivers/gpu/drm/drm_rect.c

Source file repositories/reference/linux-study-clean/drivers/gpu/drm/drm_rect.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/drm/drm_rect.c
Extension
.c
Size
9667 bytes
Lines
375
Domain
Driver Families
Bucket
drivers/gpu
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

if (rotation & DRM_MODE_REFLECT_X) {
			r->x1 = width - tmp.x2;
			r->x2 = width - tmp.x1;
		}

		if (rotation & DRM_MODE_REFLECT_Y) {
			r->y1 = height - tmp.y2;
			r->y2 = height - tmp.y1;
		}
	}

	switch (rotation & DRM_MODE_ROTATE_MASK) {
	case DRM_MODE_ROTATE_0:
		break;
	case DRM_MODE_ROTATE_90:
		tmp = *r;
		r->x1 = tmp.y1;
		r->x2 = tmp.y2;
		r->y1 = width - tmp.x2;
		r->y2 = width - tmp.x1;
		break;
	case DRM_MODE_ROTATE_180:
		tmp = *r;
		r->x1 = width - tmp.x2;
		r->x2 = width - tmp.x1;
		r->y1 = height - tmp.y2;
		r->y2 = height - tmp.y1;
		break;
	case DRM_MODE_ROTATE_270:
		tmp = *r;
		r->x1 = height - tmp.y2;
		r->x2 = height - tmp.y1;
		r->y1 = tmp.x1;
		r->y2 = tmp.x2;
		break;
	default:
		break;
	}
}
EXPORT_SYMBOL(drm_rect_rotate);

/**
 * drm_rect_rotate_inv - Inverse rotate the rectangle
 * @r: rectangle to be rotated
 * @width: Width of the coordinate space
 * @height: Height of the coordinate space
 * @rotation: Transformation whose inverse is to be applied
 *
 * Apply the inverse of @rotation to the coordinates
 * of rectangle @r.
 *
 * @width and @height combined with @rotation define
 * the location of the new origin.
 *
 * @width correcsponds to the horizontal and @height
 * to the vertical axis of the original untransformed
 * coordinate space, so that you never have to flip
 * them when doing a rotatation and its inverse.
 * That is, if you do ::
 *
 *     drm_rect_rotate(&r, width, height, rotation);
 *     drm_rect_rotate_inv(&r, width, height, rotation);
 *
 * you will always get back the original rectangle.
 */
void drm_rect_rotate_inv(struct drm_rect *r,
			 int width, int height,
			 unsigned int rotation)
{
	struct drm_rect tmp;

	switch (rotation & DRM_MODE_ROTATE_MASK) {
	case DRM_MODE_ROTATE_0:
		break;
	case DRM_MODE_ROTATE_90:
		tmp = *r;
		r->x1 = width - tmp.y2;
		r->x2 = width - tmp.y1;
		r->y1 = tmp.x1;
		r->y2 = tmp.x2;
		break;
	case DRM_MODE_ROTATE_180:
		tmp = *r;
		r->x1 = width - tmp.x2;
		r->x2 = width - tmp.x1;
		r->y1 = height - tmp.y2;
		r->y2 = height - tmp.y1;
		break;
	case DRM_MODE_ROTATE_270:
		tmp = *r;

Annotation

Implementation Notes