frontend/linux/fbdev.c

   1 /*
   2  * (C) Gražvydas "notaz" Ignotas, 2009-2010
   3  *
   4  * This work is licensed under the terms of any of these licenses
   5  * (at your option):
   6  *  - GNU GPL, version 2 or later.
   7  *  - GNU LGPL, version 2.1 or later.
   8  * See the COPYING file in the top-level directory.
   9  */
  10
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <sys/types.h>
  15 #include <sys/stat.h>
  16 #include <fcntl.h>
  17 #include <sys/ioctl.h>
  18 #include <sys/mman.h>
  19 #include <unistd.h>
  20 #include <linux/fb.h>
  21 #include <linux/matroxfb.h>
  22
  23 #include "fbdev.h"
  24
  25 struct vout_fbdev {
  26         int     fd;
  27         void    *mem;
  28         size_t  mem_size;
  29         struct  fb_var_screeninfo fbvar_old;
  30         struct  fb_var_screeninfo fbvar_new;
  31         int     buffer_write;
  32         int     fb_size;
  33         int     buffer_count;
  34         int     top_border, bottom_border;
  35 };
  36
  37 void *vout_fbdev_flip(struct vout_fbdev *fbdev)
  38 {
  39         int draw_buf;
  40
  41         if (fbdev->buffer_count < 2)
  42                 return fbdev->mem;
  43
  44         draw_buf = fbdev->buffer_write;
  45         fbdev->buffer_write++;
  46         if (fbdev->buffer_write >= fbdev->buffer_count)
  47                 fbdev->buffer_write = 0;
  48
  49         fbdev->fbvar_new.yoffset =
  50                 (fbdev->top_border + fbdev->fbvar_new.yres + fbdev->bottom_border) * draw_buf +
  51                 fbdev->top_border;
  52
  53         ioctl(fbdev->fd, FBIOPAN_DISPLAY, &fbdev->fbvar_new);
  54
  55         return (char *)fbdev->mem + fbdev->fb_size * fbdev->buffer_write;
  56 }
  57
  58 void vout_fbdev_wait_vsync(struct vout_fbdev *fbdev)
  59 {
  60         int arg = 0;
  61         ioctl(fbdev->fd, FBIO_WAITFORVSYNC, &arg);
  62 }
  63
  64 int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
  65                       int left_border, int right_border, int top_border, int bottom_border, int buffer_cnt)
  66 {
  67         int w_total = left_border + w + right_border;
  68         int h_total = top_border + h + bottom_border;
  69         size_t mem_size;
  70         int ret;
  71
  72         // unblank to be sure the mode is really accepted
  73         ioctl(fbdev->fd, FBIOBLANK, FB_BLANK_UNBLANK);
  74
  75         if (fbdev->fbvar_new.bits_per_pixel != bpp ||
  76                         w != fbdev->fbvar_new.xres ||
  77                         h != fbdev->fbvar_new.yres ||
  78                         w_total != fbdev->fbvar_new.xres_virtual ||
  79                         h_total > fbdev->fbvar_new.yres_virtual ||
  80                         left_border != fbdev->fbvar_new.xoffset) {
  81                 fbdev->fbvar_new.xres = w;
  82                 fbdev->fbvar_new.yres = h;
  83                 fbdev->fbvar_new.xres_virtual = w_total;
  84                 fbdev->fbvar_new.yres_virtual = h_total;
  85                 fbdev->fbvar_new.xoffset = left_border;
  86                 fbdev->fbvar_new.bits_per_pixel = bpp;
  87                 printf(" switching to %dx%d@%d\n", w, h, bpp);
  88                 ret = ioctl(fbdev->fd, FBIOPUT_VSCREENINFO, &fbdev->fbvar_new);
  89                 if (ret == -1) {
  90                         perror("FBIOPUT_VSCREENINFO ioctl");
  91                         return -1;
  92                 }
  93         }
  94
  95         fbdev->buffer_count = buffer_cnt;
  96
  97         if (fbdev->fbvar_new.yres_virtual < h_total * fbdev->buffer_count) {
  98                 fbdev->fbvar_new.yres_virtual = h_total * fbdev->buffer_count;
  99                 ret = ioctl(fbdev->fd, FBIOPUT_VSCREENINFO, &fbdev->fbvar_new);
 100                 if (ret == -1) {
 101                         fbdev->buffer_count = 1;
 102                         fprintf(stderr, "Warning: failed to increase virtual resolution, "
 103                                         "doublebuffering disabled\n");
 104                 }
 105         }
 106
 107         fbdev->fb_size = w_total * h_total * bpp / 8;
 108         fbdev->top_border = top_border;
 109         fbdev->bottom_border = bottom_border;
 110
 111         mem_size = fbdev->fb_size * fbdev->buffer_count;
 112         if (fbdev->mem_size >= mem_size)
 113                 return 0;
 114
 115         if (fbdev->mem != NULL)
 116                 munmap(fbdev->mem, fbdev->mem_size);
 117
 118         fbdev->mem = mmap(0, mem_size, PROT_WRITE|PROT_READ, MAP_SHARED, fbdev->fd, 0);
 119         if (fbdev->mem == MAP_FAILED && fbdev->buffer_count > 1) {
 120                 fprintf(stderr, "Warning: can't map %zd bytes, doublebuffering disabled\n", fbdev->mem_size);
 121                 fbdev->buffer_count = 1;
 122                 mem_size = fbdev->fb_size;
 123                 fbdev->mem = mmap(0, mem_size, PROT_WRITE|PROT_READ, MAP_SHARED, fbdev->fd, 0);
 124         }
 125         if (fbdev->mem == MAP_FAILED) {
 126                 fbdev->mem = NULL;
 127                 fbdev->mem_size = 0;
 128                 perror("mmap framebuffer");
 129                 return -1;
 130         }
 131
 132         fbdev->mem_size = mem_size;
 133         return 0;
 134 }
 135
 136 void vout_fbdev_clear(struct vout_fbdev *fbdev)
 137 {
 138         memset(fbdev->mem, 0, fbdev->mem_size);
 139 }
 140
 141 void vout_fbdev_clear_lines(struct vout_fbdev *fbdev, int y, int count)
 142 {
 143         int stride = fbdev->fbvar_new.xres_virtual * fbdev->fbvar_new.bits_per_pixel / 8;
 144         int i;
 145
 146         if (y + count > fbdev->top_border + fbdev->fbvar_new.yres)
 147                 count = fbdev->top_border + fbdev->fbvar_new.yres - y;
 148
 149         if (y >= 0 && count > 0)
 150                 for (i = 0; i < fbdev->buffer_count; i++)
 151                         memset((char *)fbdev->mem + fbdev->fb_size * i + y * stride, 0, stride * count);
 152 }
 153
 154 int vout_fbdev_get_fd(struct vout_fbdev *fbdev)
 155 {
 156         return fbdev->fd;
 157 }
 158
 159 struct vout_fbdev *vout_fbdev_init(const char *fbdev_name, int *w, int *h, int bpp, int buffer_cnt)
 160 {
 161         struct vout_fbdev *fbdev;
 162         int req_w, req_h;
 163         int ret;
 164
 165         fbdev = calloc(1, sizeof(*fbdev));
 166         if (fbdev == NULL)
 167                 return NULL;
 168
 169         fbdev->fd = open(fbdev_name, O_RDWR);
 170         if (fbdev->fd == -1) {
 171                 fprintf(stderr, "%s: ", fbdev_name);
 172                 perror("open");
 173                 goto fail_open;
 174         }
 175
 176         ret = ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->fbvar_old);
 177         if (ret == -1) {
 178                 perror("FBIOGET_VSCREENINFO ioctl");
 179                 goto fail;
 180         }
 181
 182         fbdev->fbvar_new = fbdev->fbvar_old;
 183
 184         req_w = fbdev->fbvar_new.xres;
 185         if (*w != 0)
 186                 req_w = *w;
 187         req_h = fbdev->fbvar_new.yres;
 188         if (*h != 0)
 189                 req_h = *h;
 190
 191         ret = vout_fbdev_resize(fbdev, req_w, req_h, bpp, 0, 0, 0, 0, buffer_cnt);
 192         if (ret != 0)
 193                 goto fail;
 194
 195         printf("%s: %ix%i@%d\n", fbdev_name, fbdev->fbvar_new.xres, fbdev->fbvar_new.yres,
 196                 fbdev->fbvar_new.bits_per_pixel);
 197         *w = fbdev->fbvar_new.xres;
 198         *h = fbdev->fbvar_new.yres;
 199
 200         memset(fbdev->mem, 0, fbdev->mem_size);
 201
 202         // some checks
 203         ret = 0;
 204         ret = ioctl(fbdev->fd, FBIO_WAITFORVSYNC, &ret);
 205         if (ret != 0)
 206                 fprintf(stderr, "Warning: vsync doesn't seem to be supported\n");
 207
 208         if (fbdev->buffer_count > 1) {
 209                 fbdev->buffer_write = 0;
 210                 fbdev->fbvar_new.yoffset = fbdev->fbvar_new.yres * (fbdev->buffer_count - 1);
 211                 ret = ioctl(fbdev->fd, FBIOPAN_DISPLAY, &fbdev->fbvar_new);
 212                 if (ret != 0) {
 213                         fbdev->buffer_count = 1;
 214                         fprintf(stderr, "Warning: can't pan display, doublebuffering disabled\n");
 215                 }
 216         }
 217
 218         printf("fbdev initialized.\n");
 219         return fbdev;
 220
 221 fail:
 222         close(fbdev->fd);
 223 fail_open:
 224         free(fbdev);
 225         return NULL;
 226 }
 227
 228 void vout_fbdev_finish(struct vout_fbdev *fbdev)
 229 {
 230         ioctl(fbdev->fd, FBIOPUT_VSCREENINFO, &fbdev->fbvar_old);
 231         if (fbdev->mem != MAP_FAILED)
 232                 munmap(fbdev->mem, fbdev->mem_size);
 233         if (fbdev->fd >= 0)
 234                 close(fbdev->fd);
 235         fbdev->mem = NULL;
 236         fbdev->fd = -1;
 237         free(fbdev);
 238 }
 239