drivers/gpu/drm/drm_rect.c

   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 #include <drm/drmP.h>
  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
  53 /**
  54  * drm_rect_clip_scaled - perform a scaled clip operation
  55  * @src: source window rectangle
  56  * @dst: destination window rectangle
  57  * @clip: clip rectangle
  58  * @hscale: horizontal scaling factor
  59  * @vscale: vertical scaling factor
  60  *
  61  * Clip rectangle @dst by rectangle @clip. Clip rectangle @src by the
  62  * same amounts multiplied by @hscale and @vscale.
  63  *
  64  * RETURNS:
  65  * %true if rectangle @dst is still visible after being clipped,
  66  * %false otherwise
  67  */
  68 bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst,
  69                           const struct drm_rect *clip,
  70                           int hscale, int vscale)
  71 {
  72         int diff;
  73
  74         diff = clip->x1 - dst->x1;
  75         if (diff > 0) {
  76                 int64_t tmp = src->x1 + (int64_t) diff * hscale;
  77                 src->x1 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
  78         }
  79         diff = clip->y1 - dst->y1;
  80         if (diff > 0) {
  81                 int64_t tmp = src->y1 + (int64_t) diff * vscale;
  82                 src->y1 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
  83         }
  84         diff = dst->x2 - clip->x2;
  85         if (diff > 0) {
  86                 int64_t tmp = src->x2 - (int64_t) diff * hscale;
  87                 src->x2 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
  88         }
  89         diff = dst->y2 - clip->y2;
  90         if (diff > 0) {
  91                 int64_t tmp = src->y2 - (int64_t) diff * vscale;
  92                 src->y2 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
  93         }
  94
  95         return drm_rect_intersect(dst, clip);
  96 }
  97 EXPORT_SYMBOL(drm_rect_clip_scaled);
  98
  99 static int drm_calc_scale(int src, int dst)
 100 {
 101         int scale = 0;
 102
 103         if (src < 0 || dst < 0)
 104                 return -EINVAL;
 105
 106         if (dst == 0)
 107                 return 0;
 108
 109         scale = src / dst;
 110
 111         return scale;
 112 }
 113
 114 /**
 115  * drm_rect_calc_hscale - calculate the horizontal scaling factor
 116  * @src: source window rectangle
 117  * @dst: destination window rectangle
 118  * @min_hscale: minimum allowed horizontal scaling factor
 119  * @max_hscale: maximum allowed horizontal scaling factor
 120  *
 121  * Calculate the horizontal scaling factor as
 122  * (@src width) / (@dst width).
 123  *
 124  * RETURNS:
 125  * The horizontal scaling factor, or errno of out of limits.
 126  */
 127 int drm_rect_calc_hscale(const struct drm_rect *src,
 128                          const struct drm_rect *dst,
 129                          int min_hscale, int max_hscale)
 130 {
 131         int src_w = drm_rect_width(src);
 132         int dst_w = drm_rect_width(dst);
 133         int hscale = drm_calc_scale(src_w, dst_w);
 134
 135         if (hscale < 0 || dst_w == 0)
 136                 return hscale;
 137
 138         if (hscale < min_hscale || hscale > max_hscale)
 139                 return -ERANGE;
 140
 141         return hscale;
 142 }
 143 EXPORT_SYMBOL(drm_rect_calc_hscale);
 144
 145 /**
 146  * drm_rect_calc_vscale - calculate the vertical scaling factor
 147  * @src: source window rectangle
 148  * @dst: destination window rectangle
 149  * @min_vscale: minimum allowed vertical scaling factor
 150  * @max_vscale: maximum allowed vertical scaling factor
 151  *
 152  * Calculate the vertical scaling factor as
 153  * (@src height) / (@dst height).
 154  *
 155  * RETURNS:
 156  * The vertical scaling factor, or errno of out of limits.
 157  */
 158 int drm_rect_calc_vscale(const struct drm_rect *src,
 159                          const struct drm_rect *dst,
 160                          int min_vscale, int max_vscale)
 161 {
 162         int src_h = drm_rect_height(src);
 163         int dst_h = drm_rect_height(dst);
 164         int vscale = drm_calc_scale(src_h, dst_h);
 165
 166         if (vscale < 0 || dst_h == 0)
 167                 return vscale;
 168
 169         if (vscale < min_vscale || vscale > max_vscale)
 170                 return -ERANGE;
 171
 172         return vscale;
 173 }
 174 EXPORT_SYMBOL(drm_rect_calc_vscale);
 175
 176 /**
 177  * drm_calc_hscale_relaxed - calculate the horizontal scaling factor
 178  * @src: source window rectangle
 179  * @dst: destination window rectangle
 180  * @min_hscale: minimum allowed horizontal scaling factor
 181  * @max_hscale: maximum allowed horizontal scaling factor
 182  *
 183  * Calculate the horizontal scaling factor as
 184  * (@src width) / (@dst width).
 185  *
 186  * If the calculated scaling factor is below @min_vscale,
 187  * decrease the height of rectangle @dst to compensate.
 188  *
 189  * If the calculated scaling factor is above @max_vscale,
 190  * decrease the height of rectangle @src to compensate.
 191  *
 192  * RETURNS:
 193  * The horizontal scaling factor.
 194  */
 195 int drm_rect_calc_hscale_relaxed(struct drm_rect *src,
 196                                  struct drm_rect *dst,
 197                                  int min_hscale, int max_hscale)
 198 {
 199         int src_w = drm_rect_width(src);
 200         int dst_w = drm_rect_width(dst);
 201         int hscale = drm_calc_scale(src_w, dst_w);
 202
 203         if (hscale < 0 || dst_w == 0)
 204                 return hscale;
 205
 206         if (hscale < min_hscale) {
 207                 int max_dst_w = src_w / min_hscale;
 208
 209                 drm_rect_adjust_size(dst, max_dst_w - dst_w, 0);
 210
 211                 return min_hscale;
 212         }
 213
 214         if (hscale > max_hscale) {
 215                 int max_src_w = dst_w * max_hscale;
 216
 217                 drm_rect_adjust_size(src, max_src_w - src_w, 0);
 218
 219                 return max_hscale;
 220         }
 221
 222         return hscale;
 223 }
 224 EXPORT_SYMBOL(drm_rect_calc_hscale_relaxed);
 225
 226 /**
 227  * drm_rect_calc_vscale_relaxed - calculate the vertical scaling factor
 228  * @src: source window rectangle
 229  * @dst: destination window rectangle
 230  * @min_vscale: minimum allowed vertical scaling factor
 231  * @max_vscale: maximum allowed vertical scaling factor
 232  *
 233  * Calculate the vertical scaling factor as
 234  * (@src height) / (@dst height).
 235  *
 236  * If the calculated scaling factor is below @min_vscale,
 237  * decrease the height of rectangle @dst to compensate.
 238  *
 239  * If the calculated scaling factor is above @max_vscale,
 240  * decrease the height of rectangle @src to compensate.
 241  *
 242  * RETURNS:
 243  * The vertical scaling factor.
 244  */
 245 int drm_rect_calc_vscale_relaxed(struct drm_rect *src,
 246                                  struct drm_rect *dst,
 247                                  int min_vscale, int max_vscale)
 248 {
 249         int src_h = drm_rect_height(src);
 250         int dst_h = drm_rect_height(dst);
 251         int vscale = drm_calc_scale(src_h, dst_h);
 252
 253         if (vscale < 0 || dst_h == 0)
 254                 return vscale;
 255
 256         if (vscale < min_vscale) {
 257                 int max_dst_h = src_h / min_vscale;
 258
 259                 drm_rect_adjust_size(dst, 0, max_dst_h - dst_h);
 260
 261                 return min_vscale;
 262         }
 263
 264         if (vscale > max_vscale) {
 265                 int max_src_h = dst_h * max_vscale;
 266
 267                 drm_rect_adjust_size(src, 0, max_src_h - src_h);
 268
 269                 return max_vscale;
 270         }
 271
 272         return vscale;
 273 }
 274 EXPORT_SYMBOL(drm_rect_calc_vscale_relaxed);
 275
 276 /**
 277  * drm_rect_debug_print - print the rectangle information
 278  * @r: rectangle to print
 279  * @fixed_point: rectangle is in 16.16 fixed point format
 280  */
 281 void drm_rect_debug_print(const struct drm_rect *r, bool fixed_point)
 282 {
 283         int w = drm_rect_width(r);
 284         int h = drm_rect_height(r);
 285
 286         if (fixed_point)
 287                 DRM_DEBUG_KMS("%d.%06ux%d.%06u%+d.%06u%+d.%06u\n",
 288                               w >> 16, ((w & 0xffff) * 15625) >> 10,
 289                               h >> 16, ((h & 0xffff) * 15625) >> 10,
 290                               r->x1 >> 16, ((r->x1 & 0xffff) * 15625) >> 10,
 291                               r->y1 >> 16, ((r->y1 & 0xffff) * 15625) >> 10);
 292         else
 293                 DRM_DEBUG_KMS("%dx%d%+d%+d\n", w, h, r->x1, r->y1);
 294 }
 295 EXPORT_SYMBOL(drm_rect_debug_print);