OpenCloudOS-Kernel/drivers/video/of_videomode.c

55 lines
1.4 KiB
C

/*
* generic videomode helper
*
* Copyright (c) 2012 Steffen Trumtrar <s.trumtrar@pengutronix.de>, Pengutronix
*
* This file is released under the GPLv2
*/
#include <linux/errno.h>
#include <linux/export.h>
#include <linux/of.h>
#include <video/display_timing.h>
#include <video/of_display_timing.h>
#include <video/of_videomode.h>
#include <video/videomode.h>
/**
* of_get_videomode - get the videomode #<index> from devicetree
* @np - devicenode with the display_timings
* @vm - set to return value
* @index - index into list of display_timings
* (Set this to OF_USE_NATIVE_MODE to use whatever mode is
* specified as native mode in the DT.)
*
* DESCRIPTION:
* Get a list of all display timings and put the one
* specified by index into *vm. This function should only be used, if
* only one videomode is to be retrieved. A driver that needs to work
* with multiple/all videomodes should work with
* of_get_display_timings instead.
**/
int of_get_videomode(struct device_node *np, struct videomode *vm,
int index)
{
struct display_timings *disp;
int ret;
disp = of_get_display_timings(np);
if (!disp) {
pr_err("%s: no timings specified\n", of_node_full_name(np));
return -EINVAL;
}
if (index == OF_USE_NATIVE_MODE)
index = disp->native_mode;
ret = videomode_from_timings(disp, vm, index);
if (ret)
return ret;
display_timings_release(disp);
return 0;
}
EXPORT_SYMBOL_GPL(of_get_videomode);