1/*
2 * Copyright 2011 Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License as published by the Free Software Foundation;
7 * either version 2, or (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTIES OR REPRESENTATIONS; without even
11 * the implied warranty of MERCHANTABILITY or FITNESS FOR
12 * A PARTICULAR PURPOSE.See the GNU General Public License
13 * for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc.,
18 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 */
20/*
21 * generic EDID driver
22 */
23
24#include <linux/slab.h>
25#include <linux/fb.h>
26#include "via_aux.h"
27#include "../edid.h"
28
29
30static const char *name = "EDID";
31
32
33static void query_edid(struct via_aux_drv *drv)
34{
35	struct fb_monspecs *spec = drv->data;
36	unsigned char edid[EDID_LENGTH];
37	bool valid = false;
38
39	if (spec) {
40		fb_destroy_modedb(spec->modedb);
41	} else {
42		spec = kmalloc(sizeof(*spec), GFP_KERNEL);
43		if (!spec)
44			return;
45	}
46
47	spec->version = spec->revision = 0;
48	if (via_aux_read(drv, 0x00, edid, EDID_LENGTH)) {
49		fb_edid_to_monspecs(edid, spec);
50		valid = spec->version || spec->revision;
51	}
52
53	if (!valid) {
54		kfree(spec);
55		spec = NULL;
56	} else
57		printk(KERN_DEBUG "EDID: %s %s\n", spec->manufacturer, spec->monitor);
58
59	drv->data = spec;
60}
61
62static const struct fb_videomode *get_preferred_mode(struct via_aux_drv *drv)
63{
64	struct fb_monspecs *spec = drv->data;
65	int i;
66
67	if (!spec || !spec->modedb || !(spec->misc & FB_MISC_1ST_DETAIL))
68		return NULL;
69
70	for (i = 0; i < spec->modedb_len; i++) {
71		if (spec->modedb[i].flag & FB_MODE_IS_FIRST &&
72			spec->modedb[i].flag & FB_MODE_IS_DETAILED)
73			return &spec->modedb[i];
74	}
75
76	return NULL;
77}
78
79static void cleanup(struct via_aux_drv *drv)
80{
81	struct fb_monspecs *spec = drv->data;
82
83	if (spec)
84		fb_destroy_modedb(spec->modedb);
85}
86
87void via_aux_edid_probe(struct via_aux_bus *bus)
88{
89	struct via_aux_drv drv = {
90		.bus	=	bus,
91		.addr	=	0x50,
92		.name	=	name,
93		.cleanup	=	cleanup,
94		.get_preferred_mode	=	get_preferred_mode};
95
96	query_edid(&drv);
97
98	/* as EDID devices can be connected/disconnected just add the driver */
99	via_aux_add(&drv);
100}
101