src/gbm/main/gbm.c

   1 /*
   2  * Copyright © 2011 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,
  16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18  * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  19  * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  20  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  22  * DEALINGS IN THE SOFTWARE.
  23  *
  24  * Authors:
  25  *    Benjamin Franzke <benjaminfranzke@googlemail.com>
  26  */
  27
  28 #define _BSD_SOURCE
  29
  30 #include <stddef.h>
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include <stdint.h>
  35
  36 #include <sys/types.h>
  37 #include <sys/stat.h>
  38 #include <unistd.h>
  39
  40 #include "gbm.h"
  41 #include "gbmint.h"
  42 #include "common.h"
  43 #include "backend.h"
  44
  45 #define ARRAY_SIZE(a) (sizeof(a)/sizeof((a)[0]))
  46
  47 struct gbm_device *devices[16];
  48
  49 static int device_num = 0;
  50
  51 /** Returns the file description for the gbm device
  52  *
  53  * \return The fd that the struct gbm_device was created with
  54  */
  55 GBM_EXPORT int
  56 gbm_device_get_fd(struct gbm_device *gbm)
  57 {
  58    return gbm->fd;
  59 }
  60
  61 /* FIXME: maybe superfluous, use udev subclass from the fd? */
  62 /** Get the backend name for the given gbm device
  63  *
  64  * \return The backend name string - this belongs to the device and must not
  65  * be freed
  66  */
  67 GBM_EXPORT const char *
  68 gbm_device_get_backend_name(struct gbm_device *gbm)
  69 {
  70    return gbm->name;
  71 }
  72
  73 /** Test if a format is supported for a given set of usage flags.
  74  *
  75  * \param gbm The created buffer manager
  76  * \param format The format to test
  77  * \param usage A bitmask of the usages to test the format against
  78  * \return 1 if the format is supported otherwise 0
  79  *
  80  * \sa enum gbm_bo_flags for the list of flags that the format can be
  81  * tested against
  82  *
  83  * \sa enum gbm_bo_format for the list of formats
  84  */
  85 int
  86 gbm_device_is_format_supported(struct gbm_device *gbm,
  87                                enum gbm_bo_format format,
  88                                uint32_t usage)
  89 {
  90    return gbm->is_format_supported(gbm, format, usage);
  91 }
  92
  93 /** Destroy the gbm device and free all resources associated with it.
  94  *
  95  * \param gbm The device created using gbm_create_device()
  96  */
  97 GBM_EXPORT void
  98 gbm_device_destroy(struct gbm_device *gbm)
  99 {
 100    gbm->refcount--;
 101    if (gbm->refcount == 0)
 102       gbm->destroy(gbm);
 103 }
 104
 105 GBM_EXPORT struct gbm_device *
 106 _gbm_mesa_get_device(int fd)
 107 {
 108    struct gbm_device *gbm = NULL;
 109    struct stat buf;
 110    dev_t dev;
 111    int i;
 112
 113    if (fd < 0 || fstat(fd, &buf) < 0 || !S_ISCHR(buf.st_mode)) {
 114       fprintf(stderr, "_gbm_mesa_get_device: invalid fd: %d\n", fd);
 115       return NULL;
 116    }
 117
 118    for (i = 0; i < device_num; ++i) {
 119       dev = devices[i]->stat.st_rdev;
 120       if (major(dev) == major(buf.st_rdev) &&
 121           minor(dev) == minor(buf.st_rdev)) {
 122          gbm = devices[i];
 123          gbm->refcount++;
 124          break;
 125       }
 126    }
 127
 128    return gbm;
 129 }
 130
 131 /** Create a gbm device for allocating buffers
 132  *
 133  * The file descriptor passed in is used by the backend to communicate with
 134  * platform for allocating the memory. For allocations using DRI this would be
 135  * the file descriptor returned when opening a device such as \c
 136  * /dev/dri/card0
 137  *
 138  * \param fd The file descriptor for an backend specific device
 139  * \return The newly created struct gbm_device. The resources associated with
 140  * the device should be freed with gbm_device_destroy() when it is no longer
 141  * needed. If the creation of the device failed NULL will be returned.
 142  */
 143 GBM_EXPORT struct gbm_device *
 144 gbm_create_device(int fd)
 145 {
 146    struct gbm_device *gbm = NULL;
 147    struct stat buf;
 148
 149    if (fd < 0 || fstat(fd, &buf) < 0 || !S_ISCHR(buf.st_mode)) {
 150       fprintf(stderr, "gbm_create_device: invalid fd: %d\n", fd);
 151       return NULL;
 152    }
 153
 154    if (device_num == 0)
 155       memset(devices, 0, sizeof devices);
 156
 157    gbm = _gbm_create_device(fd);
 158    if (gbm == NULL)
 159       return NULL;
 160
 161    gbm->dummy = gbm_create_device;
 162    gbm->stat = buf;
 163    gbm->refcount = 1;
 164
 165    if (device_num < ARRAY_SIZE(devices)-1)
 166       devices[device_num++] = gbm;
 167
 168    return gbm;
 169 }
 170
 171 /** Get the width of the buffer object
 172  *
 173  * \param bo The buffer object
 174  * \return The width of the allocated buffer object
 175  *
 176  */
 177 GBM_EXPORT unsigned int
 178 gbm_bo_get_width(struct gbm_bo *bo)
 179 {
 180    return bo->width;
 181 }
 182
 183 /** Get the height of the buffer object
 184  *
 185  * \param bo The buffer object
 186  * \return The height of the allocated buffer object
 187  */
 188 GBM_EXPORT unsigned int
 189 gbm_bo_get_height(struct gbm_bo *bo)
 190 {
 191    return bo->height;
 192 }
 193
 194 /** Get the stride of the buffer object
 195  *
 196  * This is calculated by the backend when it does the allocation in
 197  * gbm_bo_create()
 198  *
 199  * \param bo The buffer object
 200  * \return The stride of the allocated buffer object
 201  */
 202 GBM_EXPORT uint32_t
 203 gbm_bo_get_pitch(struct gbm_bo *bo)
 204 {
 205    return bo->pitch;
 206 }
 207
 208 /** Get the format of the buffer object
 209  *
 210  * The format of the pixels in the buffer.
 211  *
 212  * \param bo The buffer object
 213  * \return The format of buffer object, on of the GBM_FORMAT_* codes
 214  */
 215 GBM_EXPORT uint32_t
 216 gbm_bo_get_format(struct gbm_bo *bo)
 217 {
 218    return bo->format;
 219 }
 220
 221 /** Get the handle of the buffer object
 222  *
 223  * This is stored in the platform generic union gbm_bo_handle type. However
 224  * the format of this handle is platform specific.
 225  *
 226  * \param bo The buffer object
 227  * \return Returns the handle of the allocated buffer object
 228  */
 229 GBM_EXPORT union gbm_bo_handle
 230 gbm_bo_get_handle(struct gbm_bo *bo)
 231 {
 232    return bo->handle;
 233 }
 234
 235 /**
 236  * Destroys the given buffer object and frees all resources associated with
 237  * it.
 238  *
 239  * \param bo The buffer object
 240  */
 241 GBM_EXPORT void
 242 gbm_bo_destroy(struct gbm_bo *bo)
 243 {
 244    bo->gbm->bo_destroy(bo);
 245 }
 246
 247 /**
 248  * Allocate a buffer object for the given dimensions
 249  *
 250  * \param gbm The gbm device returned from gbm_create_device()
 251  * \param width The width for the buffer
 252  * \param height The height for the buffer
 253  * \param format The format to use for the buffer
 254  * \param usage The union of the usage flags for this buffer
 255  *
 256  * \return A newly allocated buffer that should be freed with gbm_bo_destroy()
 257  * when no longer needed. If an error occurs during allocation %NULL will be
 258  * returned.
 259  *
 260  * \sa enum gbm_bo_format for the list of formats
 261  * \sa enum gbm_bo_flags for the list of usage flags
 262  */
 263 GBM_EXPORT struct gbm_bo *
 264 gbm_bo_create(struct gbm_device *gbm,
 265               uint32_t width, uint32_t height,
 266               enum gbm_bo_format format, uint32_t usage)
 267 {
 268    if (width == 0 || height == 0)
 269       return NULL;
 270
 271    if (usage & GBM_BO_USE_CURSOR_64X64 &&
 272        (width != 64 || height != 64))
 273       return NULL;
 274
 275    return gbm->bo_create(gbm, width, height, format, usage);
 276 }
 277
 278 /**
 279  * Create a buffer object representing the contents of an EGLImage
 280  *
 281  * \param gbm The gbm device returned from gbm_create_device()
 282  * \param egl_dpy The EGLDisplay on which the EGLImage was created
 283  * \param egl_image The EGLImage to create the buffer from
 284  * \param width The width to use in the creation of the buffer object
 285  * \param height The height to use in the creation of the buffer object
 286  * \param usage The union of the usage flags for this buffer
 287  *
 288  * \return A newly allocated buffer object that should be freed with
 289  * gbm_bo_destroy() when no longer needed.
 290  *
 291  * \sa enum gbm_bo_flags for the list of usage flags
 292  *
 293  * \note The expectation is that this function will use an efficient method
 294  * for making the contents of the EGLImage available as a buffer object.
 295  */
 296 GBM_EXPORT struct gbm_bo *
 297 gbm_bo_create_from_egl_image(struct gbm_device *gbm,
 298                              void *egl_dpy, void *egl_image,
 299                              uint32_t width, uint32_t height,
 300                              uint32_t usage)
 301 {
 302    if (width == 0 || height == 0)
 303       return NULL;
 304
 305    return gbm->bo_create_from_egl_image(gbm, egl_dpy, egl_image,
 306                                         width, height, usage);
 307 }