1 /* 2 * Copyright (c) 2016 Laurent Pinchart <laurent.pinchart@ideasonboard.com> 3 * 4 * DRM core format related functions 5 * 6 * Permission to use, copy, modify, distribute, and sell this software and its 7 * documentation for any purpose is hereby granted without fee, provided that 8 * the above copyright notice appear in all copies and that both that copyright 9 * notice and this permission notice appear in supporting documentation, and 10 * that the name of the copyright holders not be used in advertising or 11 * publicity pertaining to distribution of the software without specific, 12 * written prior permission. The copyright holders make no representations 13 * about the suitability of this software for any purpose. It is provided "as 14 * is" without express or implied warranty. 15 * 16 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 17 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO 18 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR 19 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, 20 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER 21 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 22 * OF THIS SOFTWARE. 23 */ 24 25 #include <linux/bug.h> 26 #include <linux/ctype.h> 27 #include <linux/export.h> 28 #include <linux/kernel.h> 29 30 #include <drm/drmP.h> 31 #include <drm/drm_fourcc.h> 32 33 static char printable_char(int c) 34 { 35 return isascii(c) && isprint(c) ? c : '?'; 36 } 37 38 /** 39 * drm_mode_legacy_fb_format - compute drm fourcc code from legacy description 40 * @bpp: bits per pixels 41 * @depth: bit depth per pixel 42 * 43 * Computes a drm fourcc pixel format code for the given @bpp/@depth values. 44 * Useful in fbdev emulation code, since that deals in those values. 45 */ 46 uint32_t drm_mode_legacy_fb_format(uint32_t bpp, uint32_t depth) 47 { 48 uint32_t fmt; 49 50 switch (bpp) { 51 case 8: 52 fmt = DRM_FORMAT_C8; 53 break; 54 case 16: 55 if (depth == 15) 56 fmt = DRM_FORMAT_XRGB1555; 57 else 58 fmt = DRM_FORMAT_RGB565; 59 break; 60 case 24: 61 fmt = DRM_FORMAT_RGB888; 62 break; 63 case 32: 64 if (depth == 24) 65 fmt = DRM_FORMAT_XRGB8888; 66 else if (depth == 30) 67 fmt = DRM_FORMAT_XRGB2101010; 68 else 69 fmt = DRM_FORMAT_ARGB8888; 70 break; 71 default: 72 DRM_ERROR("bad bpp, assuming x8r8g8b8 pixel format\n"); 73 fmt = DRM_FORMAT_XRGB8888; 74 break; 75 } 76 77 return fmt; 78 } 79 EXPORT_SYMBOL(drm_mode_legacy_fb_format); 80 81 /** 82 * drm_get_format_name - return a string for drm fourcc format 83 * @format: format to compute name of 84 * 85 * Note that the buffer returned by this function is owned by the caller 86 * and will need to be freed using kfree(). 87 */ 88 char *drm_get_format_name(uint32_t format) 89 { 90 char *buf = kmalloc(32, M_DRM, GFP_KERNEL); 91 92 snprintf(buf, 32, 93 "%c%c%c%c %s-endian (0x%08x)", 94 printable_char(format & 0xff), 95 printable_char((format >> 8) & 0xff), 96 printable_char((format >> 16) & 0xff), 97 printable_char((format >> 24) & 0x7f), 98 format & DRM_FORMAT_BIG_ENDIAN ? "big" : "little", 99 format); 100 101 return buf; 102 } 103 EXPORT_SYMBOL(drm_get_format_name); 104 105 /** 106 * drm_fb_get_bpp_depth - get the bpp/depth values for format 107 * @format: pixel format (DRM_FORMAT_*) 108 * @depth: storage for the depth value 109 * @bpp: storage for the bpp value 110 * 111 * This only supports RGB formats here for compat with code that doesn't use 112 * pixel formats directly yet. 113 */ 114 void drm_fb_get_bpp_depth(uint32_t format, unsigned int *depth, 115 int *bpp) 116 { 117 char *format_name; 118 119 switch (format) { 120 case DRM_FORMAT_C8: 121 case DRM_FORMAT_RGB332: 122 case DRM_FORMAT_BGR233: 123 *depth = 8; 124 *bpp = 8; 125 break; 126 case DRM_FORMAT_XRGB1555: 127 case DRM_FORMAT_XBGR1555: 128 case DRM_FORMAT_RGBX5551: 129 case DRM_FORMAT_BGRX5551: 130 case DRM_FORMAT_ARGB1555: 131 case DRM_FORMAT_ABGR1555: 132 case DRM_FORMAT_RGBA5551: 133 case DRM_FORMAT_BGRA5551: 134 *depth = 15; 135 *bpp = 16; 136 break; 137 case DRM_FORMAT_RGB565: 138 case DRM_FORMAT_BGR565: 139 *depth = 16; 140 *bpp = 16; 141 break; 142 case DRM_FORMAT_RGB888: 143 case DRM_FORMAT_BGR888: 144 *depth = 24; 145 *bpp = 24; 146 break; 147 case DRM_FORMAT_XRGB8888: 148 case DRM_FORMAT_XBGR8888: 149 case DRM_FORMAT_RGBX8888: 150 case DRM_FORMAT_BGRX8888: 151 *depth = 24; 152 *bpp = 32; 153 break; 154 case DRM_FORMAT_XRGB2101010: 155 case DRM_FORMAT_XBGR2101010: 156 case DRM_FORMAT_RGBX1010102: 157 case DRM_FORMAT_BGRX1010102: 158 case DRM_FORMAT_ARGB2101010: 159 case DRM_FORMAT_ABGR2101010: 160 case DRM_FORMAT_RGBA1010102: 161 case DRM_FORMAT_BGRA1010102: 162 *depth = 30; 163 *bpp = 32; 164 break; 165 case DRM_FORMAT_ARGB8888: 166 case DRM_FORMAT_ABGR8888: 167 case DRM_FORMAT_RGBA8888: 168 case DRM_FORMAT_BGRA8888: 169 *depth = 32; 170 *bpp = 32; 171 break; 172 default: 173 format_name = drm_get_format_name(format); 174 DRM_DEBUG_KMS("unsupported pixel format %s\n", format_name); 175 kfree(format_name); 176 *depth = 0; 177 *bpp = 0; 178 break; 179 } 180 } 181 EXPORT_SYMBOL(drm_fb_get_bpp_depth); 182 183 /** 184 * drm_format_num_planes - get the number of planes for format 185 * @format: pixel format (DRM_FORMAT_*) 186 * 187 * Returns: 188 * The number of planes used by the specified pixel format. 189 */ 190 int drm_format_num_planes(uint32_t format) 191 { 192 switch (format) { 193 case DRM_FORMAT_YUV410: 194 case DRM_FORMAT_YVU410: 195 case DRM_FORMAT_YUV411: 196 case DRM_FORMAT_YVU411: 197 case DRM_FORMAT_YUV420: 198 case DRM_FORMAT_YVU420: 199 case DRM_FORMAT_YUV422: 200 case DRM_FORMAT_YVU422: 201 case DRM_FORMAT_YUV444: 202 case DRM_FORMAT_YVU444: 203 return 3; 204 case DRM_FORMAT_NV12: 205 case DRM_FORMAT_NV21: 206 case DRM_FORMAT_NV16: 207 case DRM_FORMAT_NV61: 208 case DRM_FORMAT_NV24: 209 case DRM_FORMAT_NV42: 210 return 2; 211 default: 212 return 1; 213 } 214 } 215 EXPORT_SYMBOL(drm_format_num_planes); 216 217 /** 218 * drm_format_plane_cpp - determine the bytes per pixel value 219 * @format: pixel format (DRM_FORMAT_*) 220 * @plane: plane index 221 * 222 * Returns: 223 * The bytes per pixel value for the specified plane. 224 */ 225 int drm_format_plane_cpp(uint32_t format, int plane) 226 { 227 unsigned int depth; 228 int bpp; 229 230 if (plane >= drm_format_num_planes(format)) 231 return 0; 232 233 switch (format) { 234 case DRM_FORMAT_YUYV: 235 case DRM_FORMAT_YVYU: 236 case DRM_FORMAT_UYVY: 237 case DRM_FORMAT_VYUY: 238 return 2; 239 case DRM_FORMAT_NV12: 240 case DRM_FORMAT_NV21: 241 case DRM_FORMAT_NV16: 242 case DRM_FORMAT_NV61: 243 case DRM_FORMAT_NV24: 244 case DRM_FORMAT_NV42: 245 return plane ? 2 : 1; 246 case DRM_FORMAT_YUV410: 247 case DRM_FORMAT_YVU410: 248 case DRM_FORMAT_YUV411: 249 case DRM_FORMAT_YVU411: 250 case DRM_FORMAT_YUV420: 251 case DRM_FORMAT_YVU420: 252 case DRM_FORMAT_YUV422: 253 case DRM_FORMAT_YVU422: 254 case DRM_FORMAT_YUV444: 255 case DRM_FORMAT_YVU444: 256 return 1; 257 default: 258 drm_fb_get_bpp_depth(format, &depth, &bpp); 259 return bpp >> 3; 260 } 261 } 262 EXPORT_SYMBOL(drm_format_plane_cpp); 263 264 /** 265 * drm_format_horz_chroma_subsampling - get the horizontal chroma subsampling factor 266 * @format: pixel format (DRM_FORMAT_*) 267 * 268 * Returns: 269 * The horizontal chroma subsampling factor for the 270 * specified pixel format. 271 */ 272 int drm_format_horz_chroma_subsampling(uint32_t format) 273 { 274 switch (format) { 275 case DRM_FORMAT_YUV411: 276 case DRM_FORMAT_YVU411: 277 case DRM_FORMAT_YUV410: 278 case DRM_FORMAT_YVU410: 279 return 4; 280 case DRM_FORMAT_YUYV: 281 case DRM_FORMAT_YVYU: 282 case DRM_FORMAT_UYVY: 283 case DRM_FORMAT_VYUY: 284 case DRM_FORMAT_NV12: 285 case DRM_FORMAT_NV21: 286 case DRM_FORMAT_NV16: 287 case DRM_FORMAT_NV61: 288 case DRM_FORMAT_YUV422: 289 case DRM_FORMAT_YVU422: 290 case DRM_FORMAT_YUV420: 291 case DRM_FORMAT_YVU420: 292 return 2; 293 default: 294 return 1; 295 } 296 } 297 EXPORT_SYMBOL(drm_format_horz_chroma_subsampling); 298 299 /** 300 * drm_format_vert_chroma_subsampling - get the vertical chroma subsampling factor 301 * @format: pixel format (DRM_FORMAT_*) 302 * 303 * Returns: 304 * The vertical chroma subsampling factor for the 305 * specified pixel format. 306 */ 307 int drm_format_vert_chroma_subsampling(uint32_t format) 308 { 309 switch (format) { 310 case DRM_FORMAT_YUV410: 311 case DRM_FORMAT_YVU410: 312 return 4; 313 case DRM_FORMAT_YUV420: 314 case DRM_FORMAT_YVU420: 315 case DRM_FORMAT_NV12: 316 case DRM_FORMAT_NV21: 317 return 2; 318 default: 319 return 1; 320 } 321 } 322 EXPORT_SYMBOL(drm_format_vert_chroma_subsampling); 323 324 /** 325 * drm_format_plane_width - width of the plane given the first plane 326 * @width: width of the first plane 327 * @format: pixel format 328 * @plane: plane index 329 * 330 * Returns: 331 * The width of @plane, given that the width of the first plane is @width. 332 */ 333 int drm_format_plane_width(int width, uint32_t format, int plane) 334 { 335 if (plane >= drm_format_num_planes(format)) 336 return 0; 337 338 if (plane == 0) 339 return width; 340 341 return width / drm_format_horz_chroma_subsampling(format); 342 } 343 EXPORT_SYMBOL(drm_format_plane_width); 344 345 /** 346 * drm_format_plane_height - height of the plane given the first plane 347 * @height: height of the first plane 348 * @format: pixel format 349 * @plane: plane index 350 * 351 * Returns: 352 * The height of @plane, given that the height of the first plane is @height. 353 */ 354 int drm_format_plane_height(int height, uint32_t format, int plane) 355 { 356 if (plane >= drm_format_num_planes(format)) 357 return 0; 358 359 if (plane == 0) 360 return height; 361 362 return height / drm_format_vert_chroma_subsampling(format); 363 } 364 EXPORT_SYMBOL(drm_format_plane_height); 365