1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright 2011 Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
4*4882a593Smuzhiyun */
5*4882a593Smuzhiyun /*
6*4882a593Smuzhiyun * generic EDID driver
7*4882a593Smuzhiyun */
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include <linux/slab.h>
10*4882a593Smuzhiyun #include <linux/fb.h>
11*4882a593Smuzhiyun #include "via_aux.h"
12*4882a593Smuzhiyun #include "../edid.h"
13*4882a593Smuzhiyun
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun static const char *name = "EDID";
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun
query_edid(struct via_aux_drv * drv)18*4882a593Smuzhiyun static void query_edid(struct via_aux_drv *drv)
19*4882a593Smuzhiyun {
20*4882a593Smuzhiyun struct fb_monspecs *spec = drv->data;
21*4882a593Smuzhiyun unsigned char edid[EDID_LENGTH];
22*4882a593Smuzhiyun bool valid = false;
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun if (spec) {
25*4882a593Smuzhiyun fb_destroy_modedb(spec->modedb);
26*4882a593Smuzhiyun } else {
27*4882a593Smuzhiyun spec = kmalloc(sizeof(*spec), GFP_KERNEL);
28*4882a593Smuzhiyun if (!spec)
29*4882a593Smuzhiyun return;
30*4882a593Smuzhiyun }
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun spec->version = spec->revision = 0;
33*4882a593Smuzhiyun if (via_aux_read(drv, 0x00, edid, EDID_LENGTH)) {
34*4882a593Smuzhiyun fb_edid_to_monspecs(edid, spec);
35*4882a593Smuzhiyun valid = spec->version || spec->revision;
36*4882a593Smuzhiyun }
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun if (!valid) {
39*4882a593Smuzhiyun kfree(spec);
40*4882a593Smuzhiyun spec = NULL;
41*4882a593Smuzhiyun } else
42*4882a593Smuzhiyun printk(KERN_DEBUG "EDID: %s %s\n", spec->manufacturer, spec->monitor);
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun drv->data = spec;
45*4882a593Smuzhiyun }
46*4882a593Smuzhiyun
get_preferred_mode(struct via_aux_drv * drv)47*4882a593Smuzhiyun static const struct fb_videomode *get_preferred_mode(struct via_aux_drv *drv)
48*4882a593Smuzhiyun {
49*4882a593Smuzhiyun struct fb_monspecs *spec = drv->data;
50*4882a593Smuzhiyun int i;
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun if (!spec || !spec->modedb || !(spec->misc & FB_MISC_1ST_DETAIL))
53*4882a593Smuzhiyun return NULL;
54*4882a593Smuzhiyun
55*4882a593Smuzhiyun for (i = 0; i < spec->modedb_len; i++) {
56*4882a593Smuzhiyun if (spec->modedb[i].flag & FB_MODE_IS_FIRST &&
57*4882a593Smuzhiyun spec->modedb[i].flag & FB_MODE_IS_DETAILED)
58*4882a593Smuzhiyun return &spec->modedb[i];
59*4882a593Smuzhiyun }
60*4882a593Smuzhiyun
61*4882a593Smuzhiyun return NULL;
62*4882a593Smuzhiyun }
63*4882a593Smuzhiyun
cleanup(struct via_aux_drv * drv)64*4882a593Smuzhiyun static void cleanup(struct via_aux_drv *drv)
65*4882a593Smuzhiyun {
66*4882a593Smuzhiyun struct fb_monspecs *spec = drv->data;
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun if (spec)
69*4882a593Smuzhiyun fb_destroy_modedb(spec->modedb);
70*4882a593Smuzhiyun }
71*4882a593Smuzhiyun
via_aux_edid_probe(struct via_aux_bus * bus)72*4882a593Smuzhiyun void via_aux_edid_probe(struct via_aux_bus *bus)
73*4882a593Smuzhiyun {
74*4882a593Smuzhiyun struct via_aux_drv drv = {
75*4882a593Smuzhiyun .bus = bus,
76*4882a593Smuzhiyun .addr = 0x50,
77*4882a593Smuzhiyun .name = name,
78*4882a593Smuzhiyun .cleanup = cleanup,
79*4882a593Smuzhiyun .get_preferred_mode = get_preferred_mode};
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun query_edid(&drv);
82*4882a593Smuzhiyun
83*4882a593Smuzhiyun /* as EDID devices can be connected/disconnected just add the driver */
84*4882a593Smuzhiyun via_aux_add(&drv);
85*4882a593Smuzhiyun }
86