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>
27
28 #include <drm/drm_mode.h>
29 #include <drm/drm_print.h>
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 */
drm_rect_intersect(struct drm_rect * r1,const struct drm_rect * r2)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
clip_scaled(u32 src,u32 dst,u32 clip)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
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
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 */
drm_rect_clip_scaled(struct drm_rect * src,struct drm_rect * dst,const struct drm_rect * clip)82 bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst,
83 const struct drm_rect *clip)
84 {
85 int diff;
86
87 diff = clip->x1 - dst->x1;
88 if (diff > 0) {
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;
94 }
95 diff = clip->y1 - dst->y1;
96 if (diff > 0) {
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;
102 }
103 diff = dst->x2 - clip->x2;
104 if (diff > 0) {
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;
110 }
111 diff = dst->y2 - clip->y2;
112 if (diff > 0) {
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;
118 }
119
120 return drm_rect_visible(dst);
121 }
122 EXPORT_SYMBOL(drm_rect_clip_scaled);
123
drm_calc_scale(int src,int dst)124 static int drm_calc_scale(int src, int dst)
125 {
126 int scale = 0;
127
128 if (WARN_ON(src < 0 || dst < 0))
129 return -EINVAL;
130
131 if (dst == 0)
132 return 0;
133
134 if (src > (dst << 16))
135 return DIV_ROUND_UP(src, dst);
136 else
137 scale = src / dst;
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 *
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 *
156 * RETURNS:
157 * The horizontal scaling factor, or errno of out of limits.
158 */
drm_rect_calc_hscale(const struct drm_rect * src,const struct drm_rect * dst,int min_hscale,int max_hscale)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 *
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 *
191 * RETURNS:
192 * The vertical scaling factor, or errno of out of limits.
193 */
drm_rect_calc_vscale(const struct drm_rect * src,const struct drm_rect * dst,int min_vscale,int max_vscale)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
212 /**
213 * drm_rect_debug_print - print the rectangle information
214 * @prefix: prefix string
215 * @r: rectangle to print
216 * @fixed_point: rectangle is in 16.16 fixed point format
217 */
drm_rect_debug_print(const char * prefix,const struct drm_rect * r,bool fixed_point)218 void drm_rect_debug_print(const char *prefix, const struct drm_rect *r, bool fixed_point)
219 {
220 if (fixed_point)
221 DRM_DEBUG_KMS("%s" DRM_RECT_FP_FMT "\n", prefix, DRM_RECT_FP_ARG(r));
222 else
223 DRM_DEBUG_KMS("%s" DRM_RECT_FMT "\n", prefix, DRM_RECT_ARG(r));
224 }
225 EXPORT_SYMBOL(drm_rect_debug_print);
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 */
drm_rect_rotate(struct drm_rect * r,int width,int height,unsigned int rotation)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
249 if (rotation & (DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y)) {
250 tmp = *r;
251
252 if (rotation & DRM_MODE_REFLECT_X) {
253 r->x1 = width - tmp.x2;
254 r->x2 = width - tmp.x1;
255 }
256
257 if (rotation & DRM_MODE_REFLECT_Y) {
258 r->y1 = height - tmp.y2;
259 r->y2 = height - tmp.y1;
260 }
261 }
262
263 switch (rotation & DRM_MODE_ROTATE_MASK) {
264 case DRM_MODE_ROTATE_0:
265 break;
266 case DRM_MODE_ROTATE_90:
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;
273 case DRM_MODE_ROTATE_180:
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;
280 case DRM_MODE_ROTATE_270:
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.
310 * That is, if you do ::
311 *
312 * drm_rect_rotate(&r, width, height, rotation);
313 * drm_rect_rotate_inv(&r, width, height, rotation);
314 *
315 * you will always get back the original rectangle.
316 */
drm_rect_rotate_inv(struct drm_rect * r,int width,int height,unsigned int rotation)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
323 switch (rotation & DRM_MODE_ROTATE_MASK) {
324 case DRM_MODE_ROTATE_0:
325 break;
326 case DRM_MODE_ROTATE_90:
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;
333 case DRM_MODE_ROTATE_180:
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;
340 case DRM_MODE_ROTATE_270:
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
351 if (rotation & (DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y)) {
352 tmp = *r;
353
354 if (rotation & DRM_MODE_REFLECT_X) {
355 r->x1 = width - tmp.x2;
356 r->x2 = width - tmp.x1;
357 }
358
359 if (rotation & DRM_MODE_REFLECT_Y) {
360 r->y1 = height - tmp.y2;
361 r->y2 = height - tmp.y1;
362 }
363 }
364 }
365 EXPORT_SYMBOL(drm_rect_rotate_inv);
366
