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(int src,int dst,int * clip)55 static u32 clip_scaled(int src, int dst, int *clip)
56 {
57 u64 tmp;
58
59 if (dst == 0)
60 return 0;
61
62 /* Only clip what we have. Keeps the result bounded. */
63 *clip = min(*clip, dst);
64
65 tmp = mul_u32_u32(src, dst - *clip);
66
67 /*
68 * Round toward 1.0 when clipping so that we don't accidentally
69 * change upscaling to downscaling or vice versa.
70 */
71 if (src < (dst << 16))
72 return DIV_ROUND_UP_ULL(tmp, dst);
73 else
74 return DIV_ROUND_DOWN_ULL(tmp, dst);
75 }
76
77 /**
78 * drm_rect_clip_scaled - perform a scaled clip operation
79 * @src: source window rectangle
80 * @dst: destination window rectangle
81 * @clip: clip rectangle
82 *
83 * Clip rectangle @dst by rectangle @clip. Clip rectangle @src by
84 * the corresponding amounts, retaining the vertical and horizontal scaling
85 * factors from @src to @dst.
86 *
87 * RETURNS:
88 *
89 * %true if rectangle @dst is still visible after being clipped,
90 * %false otherwise.
91 */
drm_rect_clip_scaled(struct drm_rect * src,struct drm_rect * dst,const struct drm_rect * clip)92 bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst,
93 const struct drm_rect *clip)
94 {
95 int diff;
96
97 diff = clip->x1 - dst->x1;
98 if (diff > 0) {
99 u32 new_src_w = clip_scaled(drm_rect_width(src),
100 drm_rect_width(dst), &diff);
101
102 src->x1 = src->x2 - new_src_w;
103 dst->x1 += diff;
104 }
105 diff = clip->y1 - dst->y1;
106 if (diff > 0) {
107 u32 new_src_h = clip_scaled(drm_rect_height(src),
108 drm_rect_height(dst), &diff);
109
110 src->y1 = src->y2 - new_src_h;
111 dst->y1 += diff;
112 }
113 diff = dst->x2 - clip->x2;
114 if (diff > 0) {
115 u32 new_src_w = clip_scaled(drm_rect_width(src),
116 drm_rect_width(dst), &diff);
117
118 src->x2 = src->x1 + new_src_w;
119 dst->x2 -= diff;
120 }
121 diff = dst->y2 - clip->y2;
122 if (diff > 0) {
123 u32 new_src_h = clip_scaled(drm_rect_height(src),
124 drm_rect_height(dst), &diff);
125
126 src->y2 = src->y1 + new_src_h;
127 dst->y2 -= diff;
128 }
129
130 return drm_rect_visible(dst);
131 }
132 EXPORT_SYMBOL(drm_rect_clip_scaled);
133
drm_calc_scale(int src,int dst)134 static int drm_calc_scale(int src, int dst)
135 {
136 int scale = 0;
137
138 if (WARN_ON(src < 0 || dst < 0))
139 return -EINVAL;
140
141 if (dst == 0)
142 return 0;
143
144 if (src > (dst << 16))
145 return DIV_ROUND_UP(src, dst);
146 else
147 scale = src / dst;
148
149 return scale;
150 }
151
152 /**
153 * drm_rect_calc_hscale - calculate the horizontal scaling factor
154 * @src: source window rectangle
155 * @dst: destination window rectangle
156 * @min_hscale: minimum allowed horizontal scaling factor
157 * @max_hscale: maximum allowed horizontal scaling factor
158 *
159 * Calculate the horizontal scaling factor as
160 * (@src width) / (@dst width).
161 *
162 * If the scale is below 1 << 16, round down. If the scale is above
163 * 1 << 16, round up. This will calculate the scale with the most
164 * pessimistic limit calculation.
165 *
166 * RETURNS:
167 * The horizontal scaling factor, or errno of out of limits.
168 */
drm_rect_calc_hscale(const struct drm_rect * src,const struct drm_rect * dst,int min_hscale,int max_hscale)169 int drm_rect_calc_hscale(const struct drm_rect *src,
170 const struct drm_rect *dst,
171 int min_hscale, int max_hscale)
172 {
173 int src_w = drm_rect_width(src);
174 int dst_w = drm_rect_width(dst);
175 int hscale = drm_calc_scale(src_w, dst_w);
176
177 if (hscale < 0 || dst_w == 0)
178 return hscale;
179
180 if (hscale < min_hscale || hscale > max_hscale)
181 return -ERANGE;
182
183 return hscale;
184 }
185 EXPORT_SYMBOL(drm_rect_calc_hscale);
186
187 /**
188 * drm_rect_calc_vscale - calculate the vertical scaling factor
189 * @src: source window rectangle
190 * @dst: destination window rectangle
191 * @min_vscale: minimum allowed vertical scaling factor
192 * @max_vscale: maximum allowed vertical scaling factor
193 *
194 * Calculate the vertical scaling factor as
195 * (@src height) / (@dst height).
196 *
197 * If the scale is below 1 << 16, round down. If the scale is above
198 * 1 << 16, round up. This will calculate the scale with the most
199 * pessimistic limit calculation.
200 *
201 * RETURNS:
202 * The vertical scaling factor, or errno of out of limits.
203 */
drm_rect_calc_vscale(const struct drm_rect * src,const struct drm_rect * dst,int min_vscale,int max_vscale)204 int drm_rect_calc_vscale(const struct drm_rect *src,
205 const struct drm_rect *dst,
206 int min_vscale, int max_vscale)
207 {
208 int src_h = drm_rect_height(src);
209 int dst_h = drm_rect_height(dst);
210 int vscale = drm_calc_scale(src_h, dst_h);
211
212 if (vscale < 0 || dst_h == 0)
213 return vscale;
214
215 if (vscale < min_vscale || vscale > max_vscale)
216 return -ERANGE;
217
218 return vscale;
219 }
220 EXPORT_SYMBOL(drm_rect_calc_vscale);
221
222 /**
223 * drm_rect_debug_print - print the rectangle information
224 * @prefix: prefix string
225 * @r: rectangle to print
226 * @fixed_point: rectangle is in 16.16 fixed point format
227 */
drm_rect_debug_print(const char * prefix,const struct drm_rect * r,bool fixed_point)228 void drm_rect_debug_print(const char *prefix, const struct drm_rect *r, bool fixed_point)
229 {
230 if (fixed_point)
231 DRM_DEBUG_KMS("%s" DRM_RECT_FP_FMT "\n", prefix, DRM_RECT_FP_ARG(r));
232 else
233 DRM_DEBUG_KMS("%s" DRM_RECT_FMT "\n", prefix, DRM_RECT_ARG(r));
234 }
235 EXPORT_SYMBOL(drm_rect_debug_print);
236
237 /**
238 * drm_rect_rotate - Rotate the rectangle
239 * @r: rectangle to be rotated
240 * @width: Width of the coordinate space
241 * @height: Height of the coordinate space
242 * @rotation: Transformation to be applied
243 *
244 * Apply @rotation to the coordinates of rectangle @r.
245 *
246 * @width and @height combined with @rotation define
247 * the location of the new origin.
248 *
249 * @width correcsponds to the horizontal and @height
250 * to the vertical axis of the untransformed coordinate
251 * space.
252 */
drm_rect_rotate(struct drm_rect * r,int width,int height,unsigned int rotation)253 void drm_rect_rotate(struct drm_rect *r,
254 int width, int height,
255 unsigned int rotation)
256 {
257 struct drm_rect tmp;
258
259 if (rotation & (DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y)) {
260 tmp = *r;
261
262 if (rotation & DRM_MODE_REFLECT_X) {
263 r->x1 = width - tmp.x2;
264 r->x2 = width - tmp.x1;
265 }
266
267 if (rotation & DRM_MODE_REFLECT_Y) {
268 r->y1 = height - tmp.y2;
269 r->y2 = height - tmp.y1;
270 }
271 }
272
273 switch (rotation & DRM_MODE_ROTATE_MASK) {
274 case DRM_MODE_ROTATE_0:
275 break;
276 case DRM_MODE_ROTATE_90:
277 tmp = *r;
278 r->x1 = tmp.y1;
279 r->x2 = tmp.y2;
280 r->y1 = width - tmp.x2;
281 r->y2 = width - tmp.x1;
282 break;
283 case DRM_MODE_ROTATE_180:
284 tmp = *r;
285 r->x1 = width - tmp.x2;
286 r->x2 = width - tmp.x1;
287 r->y1 = height - tmp.y2;
288 r->y2 = height - tmp.y1;
289 break;
290 case DRM_MODE_ROTATE_270:
291 tmp = *r;
292 r->x1 = height - tmp.y2;
293 r->x2 = height - tmp.y1;
294 r->y1 = tmp.x1;
295 r->y2 = tmp.x2;
296 break;
297 default:
298 break;
299 }
300 }
301 EXPORT_SYMBOL(drm_rect_rotate);
302
303 /**
304 * drm_rect_rotate_inv - Inverse rotate the rectangle
305 * @r: rectangle to be rotated
306 * @width: Width of the coordinate space
307 * @height: Height of the coordinate space
308 * @rotation: Transformation whose inverse is to be applied
309 *
310 * Apply the inverse of @rotation to the coordinates
311 * of rectangle @r.
312 *
313 * @width and @height combined with @rotation define
314 * the location of the new origin.
315 *
316 * @width correcsponds to the horizontal and @height
317 * to the vertical axis of the original untransformed
318 * coordinate space, so that you never have to flip
319 * them when doing a rotatation and its inverse.
320 * That is, if you do ::
321 *
322 * drm_rect_rotate(&r, width, height, rotation);
323 * drm_rect_rotate_inv(&r, width, height, rotation);
324 *
325 * you will always get back the original rectangle.
326 */
drm_rect_rotate_inv(struct drm_rect * r,int width,int height,unsigned int rotation)327 void drm_rect_rotate_inv(struct drm_rect *r,
328 int width, int height,
329 unsigned int rotation)
330 {
331 struct drm_rect tmp;
332
333 switch (rotation & DRM_MODE_ROTATE_MASK) {
334 case DRM_MODE_ROTATE_0:
335 break;
336 case DRM_MODE_ROTATE_90:
337 tmp = *r;
338 r->x1 = width - tmp.y2;
339 r->x2 = width - tmp.y1;
340 r->y1 = tmp.x1;
341 r->y2 = tmp.x2;
342 break;
343 case DRM_MODE_ROTATE_180:
344 tmp = *r;
345 r->x1 = width - tmp.x2;
346 r->x2 = width - tmp.x1;
347 r->y1 = height - tmp.y2;
348 r->y2 = height - tmp.y1;
349 break;
350 case DRM_MODE_ROTATE_270:
351 tmp = *r;
352 r->x1 = tmp.y1;
353 r->x2 = tmp.y2;
354 r->y1 = height - tmp.x2;
355 r->y2 = height - tmp.x1;
356 break;
357 default:
358 break;
359 }
360
361 if (rotation & (DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y)) {
362 tmp = *r;
363
364 if (rotation & DRM_MODE_REFLECT_X) {
365 r->x1 = width - tmp.x2;
366 r->x2 = width - tmp.x1;
367 }
368
369 if (rotation & DRM_MODE_REFLECT_Y) {
370 r->y1 = height - tmp.y2;
371 r->y2 = height - tmp.y1;
372 }
373 }
374 }
375 EXPORT_SYMBOL(drm_rect_rotate_inv);
376