drivers/video/of_videomode.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * generic videomode helper
   4  *
   5  * Copyright (c) 2012 Steffen Trumtrar <s.trumtrar@pengutronix.de>, Pengutronix
   6  */
   7 #include <linux/errno.h>
   8 #include <linux/export.h>
   9 #include <linux/of.h>
  10 #include <video/display_timing.h>
  11 #include <video/of_display_timing.h>
  12 #include <video/of_videomode.h>
  13 #include <video/videomode.h>
  14
  15 /**
  16  * of_get_videomode - get the videomode #<index> from devicetree
  17  * @np - devicenode with the display_timings
  18  * @vm - set to return value
  19  * @index - index into list of display_timings
  20  *          (Set this to OF_USE_NATIVE_MODE to use whatever mode is
  21  *           specified as native mode in the DT.)
  22  *
  23  * DESCRIPTION:
  24  * Get a list of all display timings and put the one
  25  * specified by index into *vm. This function should only be used, if
  26  * only one videomode is to be retrieved. A driver that needs to work
  27  * with multiple/all videomodes should work with
  28  * of_get_display_timings instead.
  29  **/
  30 int of_get_videomode(struct device_node *np, struct videomode *vm,
  31                      int index)
  32 {
  33         struct display_timings *disp;
  34         int ret;
  35
  36         disp = of_get_display_timings(np);
  37         if (!disp) {
  38                 pr_err("%pOF: no timings specified\n", np);
  39                 return -EINVAL;
  40         }
  41
  42         if (index == OF_USE_NATIVE_MODE)
  43                 index = disp->native_mode;
  44
  45         ret = videomode_from_timings(disp, vm, index);
  46
  47         display_timings_release(disp);
  48
  49         return ret;
  50 }
  51 EXPORT_SYMBOL_GPL(of_get_videomode);