[linux-2.6-block.git] / drivers / gpu / drm / drm_rect.c

/*
 * Copyright (C) 2011-2013 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/errno.h>
#include <linux/export.h>
#include <linux/kernel.h>

#include <drm/drm_mode.h>
#include <drm/drm_print.h>
#include <drm/drm_rect.h>

/**
 * drm_rect_intersect - intersect two rectangles
 * @r1: first rectangle
 * @r2: second rectangle
 *
 * Calculate the intersection of rectangles @r1 and @r2.
 * @r1 will be overwritten with the intersection.
 *
 * RETURNS:
 * %true if rectangle @r1 is still visible after the operation,
 * %false otherwise.
 */
bool drm_rect_intersect(struct drm_rect *r1, const struct drm_rect *r2)
{
	r1->x1 = max(r1->x1, r2->x1);
	r1->y1 = max(r1->y1, r2->y1);
	r1->x2 = min(r1->x2, r2->x2);
	r1->y2 = min(r1->y2, r2->y2);

	return drm_rect_visible(r1);
}
EXPORT_SYMBOL(drm_rect_intersect);

static u32 clip_scaled(u32 src, u32 dst, u32 clip)
{
	u64 tmp = mul_u32_u32(src, dst - clip);

	/*
	 * Round toward 1.0 when clipping so that we don't accidentally
	 * change upscaling to downscaling or vice versa.
	 */
	if (src < (dst << 16))
		return DIV_ROUND_UP_ULL(tmp, dst);
	else
		return DIV_ROUND_DOWN_ULL(tmp, dst);
}

/**
 * drm_rect_clip_scaled - perform a scaled clip operation
 * @src: source window rectangle
 * @dst: destination window rectangle
 * @clip: clip rectangle
 *
 * Clip rectangle @dst by rectangle @clip. Clip rectangle @src by the
 * same amounts multiplied by @hscale and @vscale.
 *
 * RETURNS:
 * %true if rectangle @dst is still visible after being clipped,
 * %false otherwise
 */
bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst,
			  const struct drm_rect *clip)
{
	int diff;

	diff = clip->x1 - dst->x1;
	if (diff > 0) {
		u32 new_src_w = clip_scaled(drm_rect_width(src),
					    drm_rect_width(dst), diff);

		src->x1 = clamp_t(int64_t, src->x2 - new_src_w, INT_MIN, INT_MAX);
		dst->x1 = clip->x1;
	}
	diff = clip->y1 - dst->y1;
	if (diff > 0) {
		u32 new_src_h = clip_scaled(drm_rect_height(src),
					    drm_rect_height(dst), diff);

		src->y1 = clamp_t(int64_t, src->y2 - new_src_h, INT_MIN, INT_MAX);
		dst->y1 = clip->y1;
	}
	diff = dst->x2 - clip->x2;
	if (diff > 0) {
		u32 new_src_w = clip_scaled(drm_rect_width(src),
					    drm_rect_width(dst), diff);

		src->x2 = clamp_t(int64_t, src->x1 + new_src_w, INT_MIN, INT_MAX);
		dst->x2 = clip->x2;
	}
	diff = dst->y2 - clip->y2;
	if (diff > 0) {
		u32 new_src_h = clip_scaled(drm_rect_height(src),
					    drm_rect_height(dst), diff);

		src->y2 = clamp_t(int64_t, src->y1 + new_src_h, INT_MIN, INT_MAX);
		dst->y2 = clip->y2;
	}

	return drm_rect_visible(dst);
}
EXPORT_SYMBOL(drm_rect_clip_scaled);

static int drm_calc_scale(int src, int dst)
{
	int scale = 0;

	if (WARN_ON(src < 0 || dst < 0))
		return -EINVAL;

	if (dst == 0)
		return 0;

	if (src > (dst << 16))
		return DIV_ROUND_UP(src, dst);
	else
		scale = src / dst;

	return scale;
}

/**
 * drm_rect_calc_hscale - calculate the horizontal scaling factor
 * @src: source window rectangle
 * @dst: destination window rectangle
 * @min_hscale: minimum allowed horizontal scaling factor
 * @max_hscale: maximum allowed horizontal scaling factor
 *
 * Calculate the horizontal scaling factor as
 * (@src width) / (@dst width).
 *
 * If the scale is below 1 << 16, round down. If the scale is above
 * 1 << 16, round up. This will calculate the scale with the most
 * pessimistic limit calculation.
 *
 * RETURNS:
 * The horizontal scaling factor, or errno of out of limits.
 */
int drm_rect_calc_hscale(const struct drm_rect *src,
			 const struct drm_rect *dst,
			 int min_hscale, int max_hscale)
{
	int src_w = drm_rect_width(src);
	int dst_w = drm_rect_width(dst);
	int hscale = drm_calc_scale(src_w, dst_w);

	if (hscale < 0 || dst_w == 0)
		return hscale;

	if (hscale < min_hscale || hscale > max_hscale)
		return -ERANGE;

	return hscale;
}
EXPORT_SYMBOL(drm_rect_calc_hscale);

/**
 * drm_rect_calc_vscale - calculate the vertical scaling factor
 * @src: source window rectangle
 * @dst: destination window rectangle
 * @min_vscale: minimum allowed vertical scaling factor
 * @max_vscale: maximum allowed vertical scaling factor
 *
 * Calculate the vertical scaling factor as
 * (@src height) / (@dst height).
 *
 * If the scale is below 1 << 16, round down. If the scale is above
 * 1 << 16, round up. This will calculate the scale with the most
 * pessimistic limit calculation.
 *
 * RETURNS:
 * The vertical scaling factor, or errno of out of limits.
 */
int drm_rect_calc_vscale(const struct drm_rect *src,
			 const struct drm_rect *dst,
			 int min_vscale, int max_vscale)
{
	int src_h = drm_rect_height(src);
	int dst_h = drm_rect_height(dst);
	int vscale = drm_calc_scale(src_h, dst_h);

	if (vscale < 0 || dst_h == 0)
		return vscale;

	if (vscale < min_vscale || vscale > max_vscale)
		return -ERANGE;

	return vscale;
}
EXPORT_SYMBOL(drm_rect_calc_vscale);

/**
 * drm_rect_debug_print - print the rectangle information
 * @prefix: prefix string
 * @r: rectangle to print
 * @fixed_point: rectangle is in 16.16 fixed point format
 */
void drm_rect_debug_print(const char *prefix, const struct drm_rect *r, bool fixed_point)
{
	if (fixed_point)
		DRM_DEBUG_KMS("%s" DRM_RECT_FP_FMT "\n", prefix, DRM_RECT_FP_ARG(r));
	else
		DRM_DEBUG_KMS("%s" DRM_RECT_FMT "\n", prefix, DRM_RECT_ARG(r));
}
EXPORT_SYMBOL(drm_rect_debug_print);

/**
 * drm_rect_rotate - Rotate the rectangle
 * @r: rectangle to be rotated
 * @width: Width of the coordinate space
 * @height: Height of the coordinate space
 * @rotation: Transformation to be applied
 *
 * Apply @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 untransformed coordinate
 * space.
 */
void drm_rect_rotate(struct drm_rect *r,
		     int width, int height,
		     unsigned int rotation)
{
	struct drm_rect tmp;

	if (rotation & (DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y)) {
		tmp = *r;

		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;
		r->x1 = tmp.y1;
		r->x2 = tmp.y2;
		r->y1 = height - tmp.x2;
		r->y2 = height - tmp.x1;
		break;
	default:
		break;
	}

	if (rotation & (DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y)) {
		tmp = *r;

		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;
		}
	}
}
EXPORT_SYMBOL(drm_rect_rotate_inv);
Commit	Line	Data
3512f976 VS	1	/*
	2	* Copyright (C) 2011-2013 Intel Corporation
	3	*
	4	* Permission is hereby granted, free of charge, to any person obtaining a
	5	* copy of this software and associated documentation files (the "Software"),
	6	* to deal in the Software without restriction, including without limitation
	7	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	8	* and/or sell copies of the Software, and to permit persons to whom the
	9	* Software is furnished to do so, subject to the following conditions:
	10	*
	11	* The above copyright notice and this permission notice (including the next
	12	* paragraph) shall be included in all copies or substantial portions of the
	13	* Software.
	14	*
	15	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	16	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	17	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	18	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	19	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	20	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	21	* SOFTWARE.
	22	*/
	23
	24	#include <linux/errno.h>
	25	#include <linux/export.h>
	26	#include <linux/kernel.h>
0500c04e SR	27
	28	#include <drm/drm_mode.h>
	29	#include <drm/drm_print.h>
3512f976 VS	30	#include <drm/drm_rect.h>
	31
	32	/**
	33	* drm_rect_intersect - intersect two rectangles
	34	* @r1: first rectangle
	35	* @r2: second rectangle
	36	*
	37	* Calculate the intersection of rectangles @r1 and @r2.
	38	* @r1 will be overwritten with the intersection.
	39	*
	40	* RETURNS:
	41	* %true if rectangle @r1 is still visible after the operation,
	42	* %false otherwise.
	43	*/
	44	bool drm_rect_intersect(struct drm_rect r1, const struct drm_rect r2)
	45	{
	46	r1->x1 = max(r1->x1, r2->x1);
	47	r1->y1 = max(r1->y1, r2->y1);
	48	r1->x2 = min(r1->x2, r2->x2);
	49	r1->y2 = min(r1->y2, r2->y2);
	50
	51	return drm_rect_visible(r1);
	52	}
	53	EXPORT_SYMBOL(drm_rect_intersect);
	54
f96bdf56 ML	55	static u32 clip_scaled(u32 src, u32 dst, u32 clip)
	56	{
	57	u64 tmp = mul_u32_u32(src, dst - clip);
	58
	59	/*
	60	* Round toward 1.0 when clipping so that we don't accidentally
	61	* change upscaling to downscaling or vice versa.
	62	*/
	63	if (src < (dst << 16))
	64	return DIV_ROUND_UP_ULL(tmp, dst);
	65	else
	66	return DIV_ROUND_DOWN_ULL(tmp, dst);
	67	}
	68
3512f976 VS	69	/**
	70	* drm_rect_clip_scaled - perform a scaled clip operation
	71	* @src: source window rectangle
	72	* @dst: destination window rectangle
	73	* @clip: clip rectangle
3512f976 VS	74	*
	75	* Clip rectangle @dst by rectangle @clip. Clip rectangle @src by the
	76	* same amounts multiplied by @hscale and @vscale.
	77	*
	78	* RETURNS:
	79	* %true if rectangle @dst is still visible after being clipped,
	80	* %false otherwise
	81	*/
	82	bool drm_rect_clip_scaled(struct drm_rect src, struct drm_rect dst,
f96bdf56	83	const struct drm_rect *clip)
3512f976 VS	84	{
	85	int diff;
	86
	87	diff = clip->x1 - dst->x1;
	88	if (diff > 0) {
f96bdf56 ML	89	u32 new_src_w = clip_scaled(drm_rect_width(src),
	90	drm_rect_width(dst), diff);
	91
	92	src->x1 = clamp_t(int64_t, src->x2 - new_src_w, INT_MIN, INT_MAX);
	93	dst->x1 = clip->x1;
3512f976 VS	94	}
	95	diff = clip->y1 - dst->y1;
	96	if (diff > 0) {
f96bdf56 ML	97	u32 new_src_h = clip_scaled(drm_rect_height(src),
	98	drm_rect_height(dst), diff);
	99
	100	src->y1 = clamp_t(int64_t, src->y2 - new_src_h, INT_MIN, INT_MAX);
	101	dst->y1 = clip->y1;
3512f976 VS	102	}
	103	diff = dst->x2 - clip->x2;
	104	if (diff > 0) {
f96bdf56 ML	105	u32 new_src_w = clip_scaled(drm_rect_width(src),
	106	drm_rect_width(dst), diff);
	107
	108	src->x2 = clamp_t(int64_t, src->x1 + new_src_w, INT_MIN, INT_MAX);
	109	dst->x2 = clip->x2;
3512f976 VS	110	}
	111	diff = dst->y2 - clip->y2;
	112	if (diff > 0) {
f96bdf56 ML	113	u32 new_src_h = clip_scaled(drm_rect_height(src),
	114	drm_rect_height(dst), diff);
	115
	116	src->y2 = clamp_t(int64_t, src->y1 + new_src_h, INT_MIN, INT_MAX);
	117	dst->y2 = clip->y2;
3512f976 VS	118	}
3512f976 VS	119
f96bdf56	120	return drm_rect_visible(dst);
3512f976 VS	121	}
3512f976 VS	122	EXPORT_SYMBOL(drm_rect_clip_scaled);
4954c428 VS	123
	124	static int drm_calc_scale(int src, int dst)
	125	{
	126	int scale = 0;
	127
1e1a5f8f	128	if (WARN_ON(src < 0 \|\| dst < 0))
4954c428 VS	129	return -EINVAL;
	130
	131	if (dst == 0)
	132	return 0;
	133
6f96f200 ML	134	if (src > (dst << 16))
	135	return DIV_ROUND_UP(src, dst);
	136	else
	137	scale = src / dst;
4954c428 VS	138
	139	return scale;
	140	}
	141
	142	/**
	143	* drm_rect_calc_hscale - calculate the horizontal scaling factor
	144	* @src: source window rectangle
	145	* @dst: destination window rectangle
	146	* @min_hscale: minimum allowed horizontal scaling factor
	147	* @max_hscale: maximum allowed horizontal scaling factor
	148	*
	149	* Calculate the horizontal scaling factor as
	150	* (@src width) / (@dst width).
	151	*
6f96f200 ML	152	* If the scale is below 1 << 16, round down. If the scale is above
	153	* 1 << 16, round up. This will calculate the scale with the most
	154	* pessimistic limit calculation.
	155	*
4954c428 VS	156	* RETURNS:
	157	* The horizontal scaling factor, or errno of out of limits.
	158	*/
	159	int drm_rect_calc_hscale(const struct drm_rect *src,
	160	const struct drm_rect *dst,
	161	int min_hscale, int max_hscale)
	162	{
	163	int src_w = drm_rect_width(src);
	164	int dst_w = drm_rect_width(dst);
	165	int hscale = drm_calc_scale(src_w, dst_w);
	166
	167	if (hscale < 0 \|\| dst_w == 0)
	168	return hscale;
	169
	170	if (hscale < min_hscale \|\| hscale > max_hscale)
	171	return -ERANGE;
	172
	173	return hscale;
	174	}
	175	EXPORT_SYMBOL(drm_rect_calc_hscale);
	176
	177	/**
	178	* drm_rect_calc_vscale - calculate the vertical scaling factor
	179	* @src: source window rectangle
	180	* @dst: destination window rectangle
	181	* @min_vscale: minimum allowed vertical scaling factor
	182	* @max_vscale: maximum allowed vertical scaling factor
	183	*
	184	* Calculate the vertical scaling factor as
	185	* (@src height) / (@dst height).
	186	*
6f96f200 ML	187	* If the scale is below 1 << 16, round down. If the scale is above
	188	* 1 << 16, round up. This will calculate the scale with the most
	189	* pessimistic limit calculation.
	190	*
4954c428 VS	191	* RETURNS:
	192	* The vertical scaling factor, or errno of out of limits.
	193	*/
	194	int drm_rect_calc_vscale(const struct drm_rect *src,
	195	const struct drm_rect *dst,
	196	int min_vscale, int max_vscale)
	197	{
	198	int src_h = drm_rect_height(src);
	199	int dst_h = drm_rect_height(dst);
	200	int vscale = drm_calc_scale(src_h, dst_h);
	201
	202	if (vscale < 0 \|\| dst_h == 0)
	203	return vscale;
	204
	205	if (vscale < min_vscale \|\| vscale > max_vscale)
	206	return -ERANGE;
	207
	208	return vscale;
	209	}
	210	EXPORT_SYMBOL(drm_rect_calc_vscale);
	211
e7272df3 VS	212	/**
e7272df3 VS	213	* drm_rect_debug_print - print the rectangle information
c70f577a	214	* @prefix: prefix string
e7272df3 VS	215	* @r: rectangle to print
	216	* @fixed_point: rectangle is in 16.16 fixed point format
	217	*/
c70f577a	218	void drm_rect_debug_print(const char prefix, const struct drm_rect r, bool fixed_point)
e7272df3	219	{
e7272df3	220	if (fixed_point)
65c7dc18	221	DRM_DEBUG_KMS("%s" DRM_RECT_FP_FMT "\n", prefix, DRM_RECT_FP_ARG(r));
e7272df3	222	else
65c7dc18	223	DRM_DEBUG_KMS("%s" DRM_RECT_FMT "\n", prefix, DRM_RECT_ARG(r));
e7272df3 VS	224	}
e7272df3 VS	225	EXPORT_SYMBOL(drm_rect_debug_print);
07074006 VS	226
	227	/**
	228	* drm_rect_rotate - Rotate the rectangle
	229	* @r: rectangle to be rotated
	230	* @width: Width of the coordinate space
	231	* @height: Height of the coordinate space
	232	* @rotation: Transformation to be applied
	233	*
	234	* Apply @rotation to the coordinates of rectangle @r.
	235	*
	236	* @width and @height combined with @rotation define
	237	* the location of the new origin.
	238	*
	239	* @width correcsponds to the horizontal and @height
	240	* to the vertical axis of the untransformed coordinate
	241	* space.
	242	*/
	243	void drm_rect_rotate(struct drm_rect *r,
	244	int width, int height,
	245	unsigned int rotation)
	246	{
	247	struct drm_rect tmp;
	248
c2c446ad	249	if (rotation & (DRM_MODE_REFLECT_X \| DRM_MODE_REFLECT_Y)) {
07074006 VS	250	tmp = *r;
07074006 VS	251
c2c446ad	252	if (rotation & DRM_MODE_REFLECT_X) {
07074006 VS	253	r->x1 = width - tmp.x2;
	254	r->x2 = width - tmp.x1;
	255	}
	256
c2c446ad	257	if (rotation & DRM_MODE_REFLECT_Y) {
07074006 VS	258	r->y1 = height - tmp.y2;
	259	r->y2 = height - tmp.y1;
	260	}
	261	}
	262
c2c446ad RF	263	switch (rotation & DRM_MODE_ROTATE_MASK) {
c2c446ad RF	264	case DRM_MODE_ROTATE_0:
07074006	265	break;
c2c446ad	266	case DRM_MODE_ROTATE_90:
07074006 VS	267	tmp = *r;
	268	r->x1 = tmp.y1;
	269	r->x2 = tmp.y2;
	270	r->y1 = width - tmp.x2;
	271	r->y2 = width - tmp.x1;
	272	break;
c2c446ad	273	case DRM_MODE_ROTATE_180:
07074006 VS	274	tmp = *r;
	275	r->x1 = width - tmp.x2;
	276	r->x2 = width - tmp.x1;
	277	r->y1 = height - tmp.y2;
	278	r->y2 = height - tmp.y1;
	279	break;
c2c446ad	280	case DRM_MODE_ROTATE_270:
07074006 VS	281	tmp = *r;
	282	r->x1 = height - tmp.y2;
	283	r->x2 = height - tmp.y1;
	284	r->y1 = tmp.x1;
	285	r->y2 = tmp.x2;
	286	break;
	287	default:
	288	break;
	289	}
	290	}
	291	EXPORT_SYMBOL(drm_rect_rotate);
	292
	293	/**
	294	* drm_rect_rotate_inv - Inverse rotate the rectangle
	295	* @r: rectangle to be rotated
	296	* @width: Width of the coordinate space
	297	* @height: Height of the coordinate space
	298	* @rotation: Transformation whose inverse is to be applied
	299	*
	300	* Apply the inverse of @rotation to the coordinates
	301	* of rectangle @r.
	302	*
	303	* @width and @height combined with @rotation define
	304	* the location of the new origin.
	305	*
	306	* @width correcsponds to the horizontal and @height
	307	* to the vertical axis of the original untransformed
	308	* coordinate space, so that you never have to flip
	309	* them when doing a rotatation and its inverse.
5edbfc47	310	* That is, if you do ::
07074006	311	*
ec667231 VS	312	* drm_rect_rotate(&r, width, height, rotation);
ec667231 VS	313	* drm_rect_rotate_inv(&r, width, height, rotation);
07074006 VS	314	*
	315	* you will always get back the original rectangle.
	316	*/
	317	void drm_rect_rotate_inv(struct drm_rect *r,
	318	int width, int height,
	319	unsigned int rotation)
	320	{
	321	struct drm_rect tmp;
	322
c2c446ad RF	323	switch (rotation & DRM_MODE_ROTATE_MASK) {
c2c446ad RF	324	case DRM_MODE_ROTATE_0:
07074006	325	break;
c2c446ad	326	case DRM_MODE_ROTATE_90:
07074006 VS	327	tmp = *r;
	328	r->x1 = width - tmp.y2;
	329	r->x2 = width - tmp.y1;
	330	r->y1 = tmp.x1;
	331	r->y2 = tmp.x2;
	332	break;
c2c446ad	333	case DRM_MODE_ROTATE_180:
07074006 VS	334	tmp = *r;
	335	r->x1 = width - tmp.x2;
	336	r->x2 = width - tmp.x1;
	337	r->y1 = height - tmp.y2;
	338	r->y2 = height - tmp.y1;
	339	break;
c2c446ad	340	case DRM_MODE_ROTATE_270:
07074006 VS	341	tmp = *r;
	342	r->x1 = tmp.y1;
	343	r->x2 = tmp.y2;
	344	r->y1 = height - tmp.x2;
	345	r->y2 = height - tmp.x1;
	346	break;
	347	default:
	348	break;
	349	}
	350
c2c446ad	351	if (rotation & (DRM_MODE_REFLECT_X \| DRM_MODE_REFLECT_Y)) {
07074006 VS	352	tmp = *r;
07074006 VS	353
c2c446ad	354	if (rotation & DRM_MODE_REFLECT_X) {
07074006 VS	355	r->x1 = width - tmp.x2;
	356	r->x2 = width - tmp.x1;
	357	}
	358
c2c446ad	359	if (rotation & DRM_MODE_REFLECT_Y) {
07074006 VS	360	r->y1 = height - tmp.y2;
	361	r->y2 = height - tmp.y1;
	362	}
	363	}
	364	}
	365	EXPORT_SYMBOL(drm_rect_rotate_inv);