@@ -31,6 +31,7 @@
#include <linux/pci.h>
#include <linux/slab.h>
#include <video/edid.h>
+#include <video/of_videomode.h>
#include <video/videomode.h>
#ifdef CONFIG_PPC_OF
#include <asm/prom.h>
@@ -1425,6 +1426,47 @@ int fb_videomode_from_videomode(const struct videomode *vm,
EXPORT_SYMBOL_GPL(fb_videomode_from_videomode);
#endif
+#if IS_ENABLED(CONFIG_OF_VIDEOMODE)
+static inline void dump_fb_videomode(const struct fb_videomode *m)
+{
+ pr_debug("fb_videomode = %ux%u@%uHz (%ukHz) %u %u %u %u %u %u %u %u %u\n",
+ m->xres, m->yres, m->refresh, m->pixclock, m->left_margin,
+ m->right_margin, m->upper_margin, m->lower_margin,
+ m->hsync_len, m->vsync_len, m->sync, m->vmode, m->flag);
+}
+
+/**
+ * of_get_fb_videomode - get a fb_videomode from devicetree
+ * @np: device_node with the timing specification
+ * @fb: will be set to the return value
+ * @index: index into the list of display timings in devicetree
+ *
+ * DESCRIPTION:
+ * This function is expensive and should only be used, if only one mode is to be
+ * read from DT. To get multiple modes start with of_get_display_timings ond
+ * work with that instead.
+ */
+int of_get_fb_videomode(struct device_node *np, struct fb_videomode *fb,
+ int index)
+{
+ struct videomode vm;
+ int ret;
+
+ ret = of_get_videomode(np, &vm, index);
+ if (ret)
+ return ret;
+
+ fb_videomode_from_videomode(&vm, fb);
+
+ pr_debug("%s: got %dx%d display mode from %s\n",
+ of_node_full_name(np), vm.hactive, vm.vactive, np->name);
+ dump_fb_videomode(fb);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_get_fb_videomode);
+#endif
+
#else
int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
{
@@ -20,6 +20,7 @@ struct fb_info;
struct device;
struct file;
struct videomode;
+struct device_node;
/* Definitions below are used in the parsed monitor specs */
#define FB_DPMS_ACTIVE_OFF 1
@@ -715,6 +716,9 @@ extern void fb_destroy_modedb(struct fb_videomode *modedb);
extern int fb_find_mode_cvt(struct fb_videomode *mode, int margins, int rb);
extern unsigned char *fb_ddc_read(struct i2c_adapter *adapter);
+extern int of_get_fb_videomode(struct device_node *np,
+ struct fb_videomode *fb,
+ int index);
extern int fb_videomode_from_videomode(const struct videomode *vm,
struct fb_videomode *fbmode);