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