xref: /openbmc/linux/drivers/video/fbdev/nvidia/nv_of.c (revision c819e2cf)
1 /*
2  * linux/drivers/video/nvidia/nv_of.c
3  *
4  * Copyright 2004 Antonino A. Daplas <adaplas @pol.net>
5  *
6  * Based on rivafb-i2c.c
7  *
8  * This file is subject to the terms and conditions of the GNU General Public
9  * License.  See the file COPYING in the main directory of this archive
10  * for more details.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/delay.h>
16 #include <linux/gfp.h>
17 #include <linux/pci.h>
18 #include <linux/fb.h>
19 
20 #include <asm/io.h>
21 
22 #include <asm/prom.h>
23 #include <asm/pci-bridge.h>
24 
25 #include "nv_type.h"
26 #include "nv_local.h"
27 #include "nv_proto.h"
28 
29 #include "../edid.h"
30 
31 int nvidia_probe_of_connector(struct fb_info *info, int conn, u8 **out_edid)
32 {
33 	struct nvidia_par *par = info->par;
34 	struct device_node *parent, *dp;
35 	const unsigned char *pedid = NULL;
36 	static char *propnames[] = {
37 		"DFP,EDID", "LCD,EDID", "EDID", "EDID1",
38 		"EDID,B", "EDID,A", NULL };
39 	int i;
40 
41 	parent = pci_device_to_OF_node(par->pci_dev);
42 	if (parent == NULL)
43 		return -1;
44 	if (par->twoHeads) {
45 		const char *pname;
46 		int len;
47 
48 		for (dp = NULL;
49 		     (dp = of_get_next_child(parent, dp)) != NULL;) {
50 			pname = of_get_property(dp, "name", NULL);
51 			if (!pname)
52 				continue;
53 			len = strlen(pname);
54 			if ((pname[len-1] == 'A' && conn == 1) ||
55 			    (pname[len-1] == 'B' && conn == 2)) {
56 				for (i = 0; propnames[i] != NULL; ++i) {
57 					pedid = of_get_property(dp,
58 							propnames[i], NULL);
59 					if (pedid != NULL)
60 						break;
61 				}
62 				of_node_put(dp);
63 				break;
64 			}
65 		}
66 	}
67 	if (pedid == NULL) {
68 		for (i = 0; propnames[i] != NULL; ++i) {
69 			pedid = of_get_property(parent, propnames[i], NULL);
70 			if (pedid != NULL)
71 				break;
72 		}
73 	}
74 	if (pedid) {
75 		*out_edid = kmemdup(pedid, EDID_LENGTH, GFP_KERNEL);
76 		if (*out_edid == NULL)
77 			return -1;
78 		printk(KERN_DEBUG "nvidiafb: Found OF EDID for head %d\n", conn);
79 		return 0;
80 	}
81 	return -1;
82 }
83