summaryrefslogtreecommitdiffstats
path: root/drivers/video/nvidia/nv_backlight.c
blob: 43f62d8ee41d8e3f0417c75757ffd1864e881bfb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
/*
 * Backlight code for nVidia based graphic cards
 *
 * Copyright 2004 Antonino Daplas <adaplas@pol.net>
 * Copyright (c) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/backlight.h>
#include <linux/fb.h>
#include <linux/pci.h>

#ifdef CONFIG_PMAC_BACKLIGHT
#include <asm/backlight.h>
#endif

#include "nv_local.h"
#include "nv_type.h"
#include "nv_proto.h"

/* We do not have any information about which values are allowed, thus
 * we used safe values.
 */
#define MIN_LEVEL 0x158
#define MAX_LEVEL 0x534
#define LEVEL_STEP ((MAX_LEVEL - MIN_LEVEL) / FB_BACKLIGHT_MAX)

static int nvidia_bl_get_level_brightness(struct nvidia_par *par,
		int level)
{
	struct fb_info *info = pci_get_drvdata(par->pci_dev);
	int nlevel;

	/* Get and convert the value */
	/* No locking of bl_curve since we read a single value */
	nlevel = MIN_LEVEL + info->bl_curve[level] * LEVEL_STEP;

	if (nlevel < 0)
		nlevel = 0;
	else if (nlevel < MIN_LEVEL)
		nlevel = MIN_LEVEL;
	else if (nlevel > MAX_LEVEL)
		nlevel = MAX_LEVEL;

	return nlevel;
}

static int nvidia_bl_update_status(struct backlight_device *bd)
{
	struct nvidia_par *par = class_get_devdata(&bd->class_dev);
	u32 tmp_pcrt, tmp_pmc, fpcontrol;
	int level;

	if (!par->FlatPanel)
		return 0;

	if (bd->props.power != FB_BLANK_UNBLANK ||
	    bd->props.fb_blank != FB_BLANK_UNBLANK)
		level = 0;
	else
		level = bd->props.brightness;

	tmp_pmc = NV_RD32(par->PMC, 0x10F0) & 0x0000FFFF;
	tmp_pcrt = NV_RD32(par->PCRTC0, 0x081C) & 0xFFFFFFFC;
	fpcontrol = NV_RD32(par->PRAMDAC, 0x0848) & 0xCFFFFFCC;

	if (level > 0) {
		tmp_pcrt |= 0x1;
		tmp_pmc |= (1 << 31); /* backlight bit */
		tmp_pmc |= nvidia_bl_get_level_brightness(par, level) << 16;
		fpcontrol |= par->fpSyncs;
	} else
		fpcontrol |= 0x20000022;

	NV_WR32(par->PCRTC0, 0x081C, tmp_pcrt);
	NV_WR32(par->PMC, 0x10F0, tmp_pmc);
	NV_WR32(par->PRAMDAC, 0x848, fpcontrol);

	return 0;
}

static int nvidia_bl_get_brightness(struct backlight_device *bd)
{
	return bd->props.brightness;
}

static struct backlight_ops nvidia_bl_ops = {
	.get_brightness = nvidia_bl_get_brightness,
	.update_status	= nvidia_bl_update_status,
};

void nvidia_bl_init(struct nvidia_par *par)
{
	struct fb_info *info = pci_get_drvdata(par->pci_dev);
	struct backlight_device *bd;
	char name[12];

	if (!par->FlatPanel)
		return;

#ifdef CONFIG_PMAC_BACKLIGHT
	if (!machine_is(powermac) ||
	    !pmac_has_backlight_type("mnca"))
		return;
#endif

	snprintf(name, sizeof(name), "nvidiabl%d", info->node);

	bd = backlight_device_register(name, info->dev, par, &nvidia_bl_ops);
	if (IS_ERR(bd)) {
		info->bl_dev = NULL;
		printk(KERN_WARNING "nvidia: Backlight registration failed\n");
		goto error;
	}

	info->bl_dev = bd;
	fb_bl_default_curve(info, 0,
		0x158 * FB_BACKLIGHT_MAX / MAX_LEVEL,
		0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL);

	bd->props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
	bd->props.brightness = bd->props.max_brightness;
	bd->props.power = FB_BLANK_UNBLANK;
	backlight_update_status(bd);

	printk("nvidia: Backlight initialized (%s)\n", name);

	return;

error:
	return;
}

void nvidia_bl_exit(struct nvidia_par *par)
{
	struct fb_info *info = pci_get_drvdata(par->pci_dev);
	struct backlight_device *bd = info->bl_dev;

	backlight_device_unregister(bd);
	printk("nvidia: Backlight unloaded\n");
}