drivers/media/video/omap/omap_voutlib.c

   1 /*
   2  * omap_voutlib.c
   3  *
   4  * Copyright (C) 2005-2010 Texas Instruments.
   5  *
   6  * This file is licensed under the terms of the GNU General Public License
   7  * version 2. This program is licensed "as is" without any warranty of any
   8  * kind, whether express or implied.
   9  *
  10  * Based on the OMAP2 camera driver
  11  * Video-for-Linux (Version 2) camera capture driver for
  12  * the OMAP24xx camera controller.
  13  *
  14  * Author: Andy Lowe (source@mvista.com)
  15  *
  16  * Copyright (C) 2004 MontaVista Software, Inc.
  17  * Copyright (C) 2010 Texas Instruments.
  18  *
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/errno.h>
  23 #include <linux/kernel.h>
  24 #include <linux/types.h>
  25 #include <linux/videodev2.h>
  26
  27 #include <plat/cpu.h>
  28
  29 MODULE_AUTHOR("Texas Instruments");
  30 MODULE_DESCRIPTION("OMAP Video library");
  31 MODULE_LICENSE("GPL");
  32
  33 /* Return the default overlay cropping rectangle in crop given the image
  34  * size in pix and the video display size in fbuf.  The default
  35  * cropping rectangle is the largest rectangle no larger than the capture size
  36  * that will fit on the display.  The default cropping rectangle is centered in
  37  * the image.  All dimensions and offsets are rounded down to even numbers.
  38  */
  39 void omap_vout_default_crop(struct v4l2_pix_format *pix,
  40                   struct v4l2_framebuffer *fbuf, struct v4l2_rect *crop)
  41 {
  42         crop->width = (pix->width < fbuf->fmt.width) ?
  43                 pix->width : fbuf->fmt.width;
  44         crop->height = (pix->height < fbuf->fmt.height) ?
  45                 pix->height : fbuf->fmt.height;
  46         crop->width &= ~1;
  47         crop->height &= ~1;
  48         crop->left = ((pix->width - crop->width) >> 1) & ~1;
  49         crop->top = ((pix->height - crop->height) >> 1) & ~1;
  50 }
  51 EXPORT_SYMBOL_GPL(omap_vout_default_crop);
  52
  53 /* Given a new render window in new_win, adjust the window to the
  54  * nearest supported configuration.  The adjusted window parameters are
  55  * returned in new_win.
  56  * Returns zero if succesful, or -EINVAL if the requested window is
  57  * impossible and cannot reasonably be adjusted.
  58  */
  59 int omap_vout_try_window(struct v4l2_framebuffer *fbuf,
  60                         struct v4l2_window *new_win)
  61 {
  62         struct v4l2_rect try_win;
  63
  64         /* make a working copy of the new_win rectangle */
  65         try_win = new_win->w;
  66
  67         /* adjust the preview window so it fits on the display by clipping any
  68          * offscreen areas
  69          */
  70         if (try_win.left < 0) {
  71                 try_win.width += try_win.left;
  72                 try_win.left = 0;
  73         }
  74         if (try_win.top < 0) {
  75                 try_win.height += try_win.top;
  76                 try_win.top = 0;
  77         }
  78         try_win.width = (try_win.width < fbuf->fmt.width) ?
  79                 try_win.width : fbuf->fmt.width;
  80         try_win.height = (try_win.height < fbuf->fmt.height) ?
  81                 try_win.height : fbuf->fmt.height;
  82         if (try_win.left + try_win.width > fbuf->fmt.width)
  83                 try_win.width = fbuf->fmt.width - try_win.left;
  84         if (try_win.top + try_win.height > fbuf->fmt.height)
  85                 try_win.height = fbuf->fmt.height - try_win.top;
  86         try_win.width &= ~1;
  87         try_win.height &= ~1;
  88
  89         if (try_win.width <= 0 || try_win.height <= 0)
  90                 return -EINVAL;
  91
  92         /* We now have a valid preview window, so go with it */
  93         new_win->w = try_win;
  94         new_win->field = V4L2_FIELD_ANY;
  95         return 0;
  96 }
  97 EXPORT_SYMBOL_GPL(omap_vout_try_window);
  98
  99 /* Given a new render window in new_win, adjust the window to the
 100  * nearest supported configuration.  The image cropping window in crop
 101  * will also be adjusted if necessary.  Preference is given to keeping the
 102  * the window as close to the requested configuration as possible.  If
 103  * successful, new_win, vout->win, and crop are updated.
 104  * Returns zero if succesful, or -EINVAL if the requested preview window is
 105  * impossible and cannot reasonably be adjusted.
 106  */
 107 int omap_vout_new_window(struct v4l2_rect *crop,
 108                 struct v4l2_window *win, struct v4l2_framebuffer *fbuf,
 109                 struct v4l2_window *new_win)
 110 {
 111         int err;
 112
 113         err = omap_vout_try_window(fbuf, new_win);
 114         if (err)
 115                 return err;
 116
 117         /* update our preview window */
 118         win->w = new_win->w;
 119         win->field = new_win->field;
 120         win->chromakey = new_win->chromakey;
 121
 122         /* Adjust the cropping window to allow for resizing limitation */
 123         if (cpu_is_omap24xx()) {
 124                 /* For 24xx limit is 8x to 1/2x scaling. */
 125                 if ((crop->height/win->w.height) >= 2)
 126                         crop->height = win->w.height * 2;
 127
 128                 if ((crop->width/win->w.width) >= 2)
 129                         crop->width = win->w.width * 2;
 130
 131                 if (crop->width > 768) {
 132                         /* The OMAP2420 vertical resizing line buffer is 768
 133                          * pixels wide. If the cropped image is wider than
 134                          * 768 pixels then it cannot be vertically resized.
 135                          */
 136                         if (crop->height != win->w.height)
 137                                 crop->width = 768;
 138                 }
 139         } else if (cpu_is_omap34xx()) {
 140                 /* For 34xx limit is 8x to 1/4x scaling. */
 141                 if ((crop->height/win->w.height) >= 4)
 142                         crop->height = win->w.height * 4;
 143
 144                 if ((crop->width/win->w.width) >= 4)
 145                         crop->width = win->w.width * 4;
 146         }
 147         return 0;
 148 }
 149 EXPORT_SYMBOL_GPL(omap_vout_new_window);
 150
 151 /* Given a new cropping rectangle in new_crop, adjust the cropping rectangle to
 152  * the nearest supported configuration.  The image render window in win will
 153  * also be adjusted if necessary.  The preview window is adjusted such that the
 154  * horizontal and vertical rescaling ratios stay constant.  If the render
 155  * window would fall outside the display boundaries, the cropping rectangle
 156  * will also be adjusted to maintain the rescaling ratios.  If successful, crop
 157  * and win are updated.
 158  * Returns zero if succesful, or -EINVAL if the requested cropping rectangle is
 159  * impossible and cannot reasonably be adjusted.
 160  */
 161 int omap_vout_new_crop(struct v4l2_pix_format *pix,
 162               struct v4l2_rect *crop, struct v4l2_window *win,
 163               struct v4l2_framebuffer *fbuf, const struct v4l2_rect *new_crop)
 164 {
 165         struct v4l2_rect try_crop;
 166         unsigned long vresize, hresize;
 167
 168         /* make a working copy of the new_crop rectangle */
 169         try_crop = *new_crop;
 170
 171         /* adjust the cropping rectangle so it fits in the image */
 172         if (try_crop.left < 0) {
 173                 try_crop.width += try_crop.left;
 174                 try_crop.left = 0;
 175         }
 176         if (try_crop.top < 0) {
 177                 try_crop.height += try_crop.top;
 178                 try_crop.top = 0;
 179         }
 180         try_crop.width = (try_crop.width < pix->width) ?
 181                 try_crop.width : pix->width;
 182         try_crop.height = (try_crop.height < pix->height) ?
 183                 try_crop.height : pix->height;
 184         if (try_crop.left + try_crop.width > pix->width)
 185                 try_crop.width = pix->width - try_crop.left;
 186         if (try_crop.top + try_crop.height > pix->height)
 187                 try_crop.height = pix->height - try_crop.top;
 188
 189         try_crop.width &= ~1;
 190         try_crop.height &= ~1;
 191
 192         if (try_crop.width <= 0 || try_crop.height <= 0)
 193                 return -EINVAL;
 194
 195         if (cpu_is_omap24xx()) {
 196                 if (crop->height != win->w.height) {
 197                         /* If we're resizing vertically, we can't support a
 198                          * crop width wider than 768 pixels.
 199                          */
 200                         if (try_crop.width > 768)
 201                                 try_crop.width = 768;
 202                 }
 203         }
 204         /* vertical resizing */
 205         vresize = (1024 * crop->height) / win->w.height;
 206         if (cpu_is_omap24xx() && (vresize > 2048))
 207                 vresize = 2048;
 208         else if (cpu_is_omap34xx() && (vresize > 4096))
 209                 vresize = 4096;
 210
 211         win->w.height = ((1024 * try_crop.height) / vresize) & ~1;
 212         if (win->w.height == 0)
 213                 win->w.height = 2;
 214         if (win->w.height + win->w.top > fbuf->fmt.height) {
 215                 /* We made the preview window extend below the bottom of the
 216                  * display, so clip it to the display boundary and resize the
 217                  * cropping height to maintain the vertical resizing ratio.
 218                  */
 219                 win->w.height = (fbuf->fmt.height - win->w.top) & ~1;
 220                 if (try_crop.height == 0)
 221                         try_crop.height = 2;
 222         }
 223         /* horizontal resizing */
 224         hresize = (1024 * crop->width) / win->w.width;
 225         if (cpu_is_omap24xx() && (hresize > 2048))
 226                 hresize = 2048;
 227         else if (cpu_is_omap34xx() && (hresize > 4096))
 228                 hresize = 4096;
 229
 230         win->w.width = ((1024 * try_crop.width) / hresize) & ~1;
 231         if (win->w.width == 0)
 232                 win->w.width = 2;
 233         if (win->w.width + win->w.left > fbuf->fmt.width) {
 234                 /* We made the preview window extend past the right side of the
 235                  * display, so clip it to the display boundary and resize the
 236                  * cropping width to maintain the horizontal resizing ratio.
 237                  */
 238                 win->w.width = (fbuf->fmt.width - win->w.left) & ~1;
 239                 if (try_crop.width == 0)
 240                         try_crop.width = 2;
 241         }
 242         if (cpu_is_omap24xx()) {
 243                 if ((try_crop.height/win->w.height) >= 2)
 244                         try_crop.height = win->w.height * 2;
 245
 246                 if ((try_crop.width/win->w.width) >= 2)
 247                         try_crop.width = win->w.width * 2;
 248
 249                 if (try_crop.width > 768) {
 250                         /* The OMAP2420 vertical resizing line buffer is
 251                          * 768 pixels wide.  If the cropped image is wider
 252                          * than 768 pixels then it cannot be vertically resized.
 253                          */
 254                         if (try_crop.height != win->w.height)
 255                                 try_crop.width = 768;
 256                 }
 257         } else if (cpu_is_omap34xx()) {
 258                 if ((try_crop.height/win->w.height) >= 4)
 259                         try_crop.height = win->w.height * 4;
 260
 261                 if ((try_crop.width/win->w.width) >= 4)
 262                         try_crop.width = win->w.width * 4;
 263         }
 264         /* update our cropping rectangle and we're done */
 265         *crop = try_crop;
 266         return 0;
 267 }
 268 EXPORT_SYMBOL_GPL(omap_vout_new_crop);
 269
 270 /* Given a new format in pix and fbuf,  crop and win
 271  * structures are initialized to default values. crop
 272  * is initialized to the largest window size that will fit on the display.  The
 273  * crop window is centered in the image. win is initialized to
 274  * the same size as crop and is centered on the display.
 275  * All sizes and offsets are constrained to be even numbers.
 276  */
 277 void omap_vout_new_format(struct v4l2_pix_format *pix,
 278                 struct v4l2_framebuffer *fbuf, struct v4l2_rect *crop,
 279                 struct v4l2_window *win)
 280 {
 281         /* crop defines the preview source window in the image capture
 282          * buffer
 283          */
 284         omap_vout_default_crop(pix, fbuf, crop);
 285
 286         /* win defines the preview target window on the display */
 287         win->w.width = crop->width;
 288         win->w.height = crop->height;
 289         win->w.left = ((fbuf->fmt.width - win->w.width) >> 1) & ~1;
 290         win->w.top = ((fbuf->fmt.height - win->w.height) >> 1) & ~1;
 291 }
 292 EXPORT_SYMBOL_GPL(omap_vout_new_format);
 293