pcmcia: CompactFlash driver for PA Semi Electra boards
[pv_ops_mirror.git] / drivers / video / nvidia / nv_backlight.c
blob443e3c85a9a0a677c12c2840899b55c209b261be
1 /*
2 * Backlight code for nVidia based graphic cards
4 * Copyright 2004 Antonino Daplas <adaplas@pol.net>
5 * Copyright (c) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 #include <linux/backlight.h>
13 #include <linux/fb.h>
14 #include <linux/pci.h>
16 #ifdef CONFIG_PMAC_BACKLIGHT
17 #include <asm/backlight.h>
18 #endif
20 #include "nv_local.h"
21 #include "nv_type.h"
22 #include "nv_proto.h"
24 /* We do not have any information about which values are allowed, thus
25 * we used safe values.
27 #define MIN_LEVEL 0x158
28 #define MAX_LEVEL 0x534
29 #define LEVEL_STEP ((MAX_LEVEL - MIN_LEVEL) / FB_BACKLIGHT_MAX)
31 static int nvidia_bl_get_level_brightness(struct nvidia_par *par,
32 int level)
34 struct fb_info *info = pci_get_drvdata(par->pci_dev);
35 int nlevel;
37 /* Get and convert the value */
38 /* No locking of bl_curve since we read a single value */
39 nlevel = MIN_LEVEL + info->bl_curve[level] * LEVEL_STEP;
41 if (nlevel < 0)
42 nlevel = 0;
43 else if (nlevel < MIN_LEVEL)
44 nlevel = MIN_LEVEL;
45 else if (nlevel > MAX_LEVEL)
46 nlevel = MAX_LEVEL;
48 return nlevel;
51 static int nvidia_bl_update_status(struct backlight_device *bd)
53 struct nvidia_par *par = bl_get_data(bd);
54 u32 tmp_pcrt, tmp_pmc, fpcontrol;
55 int level;
57 if (!par->FlatPanel)
58 return 0;
60 if (bd->props.power != FB_BLANK_UNBLANK ||
61 bd->props.fb_blank != FB_BLANK_UNBLANK)
62 level = 0;
63 else
64 level = bd->props.brightness;
66 tmp_pmc = NV_RD32(par->PMC, 0x10F0) & 0x0000FFFF;
67 tmp_pcrt = NV_RD32(par->PCRTC0, 0x081C) & 0xFFFFFFFC;
68 fpcontrol = NV_RD32(par->PRAMDAC, 0x0848) & 0xCFFFFFCC;
70 if (level > 0) {
71 tmp_pcrt |= 0x1;
72 tmp_pmc |= (1 << 31); /* backlight bit */
73 tmp_pmc |= nvidia_bl_get_level_brightness(par, level) << 16;
74 fpcontrol |= par->fpSyncs;
75 } else
76 fpcontrol |= 0x20000022;
78 NV_WR32(par->PCRTC0, 0x081C, tmp_pcrt);
79 NV_WR32(par->PMC, 0x10F0, tmp_pmc);
80 NV_WR32(par->PRAMDAC, 0x848, fpcontrol);
82 return 0;
85 static int nvidia_bl_get_brightness(struct backlight_device *bd)
87 return bd->props.brightness;
90 static struct backlight_ops nvidia_bl_ops = {
91 .get_brightness = nvidia_bl_get_brightness,
92 .update_status = nvidia_bl_update_status,
95 void nvidia_bl_init(struct nvidia_par *par)
97 struct fb_info *info = pci_get_drvdata(par->pci_dev);
98 struct backlight_device *bd;
99 char name[12];
101 if (!par->FlatPanel)
102 return;
104 #ifdef CONFIG_PMAC_BACKLIGHT
105 if (!machine_is(powermac) ||
106 !pmac_has_backlight_type("mnca"))
107 return;
108 #endif
110 snprintf(name, sizeof(name), "nvidiabl%d", info->node);
112 bd = backlight_device_register(name, info->dev, par, &nvidia_bl_ops);
113 if (IS_ERR(bd)) {
114 info->bl_dev = NULL;
115 printk(KERN_WARNING "nvidia: Backlight registration failed\n");
116 goto error;
119 info->bl_dev = bd;
120 fb_bl_default_curve(info, 0,
121 0x158 * FB_BACKLIGHT_MAX / MAX_LEVEL,
122 0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL);
124 bd->props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
125 bd->props.brightness = bd->props.max_brightness;
126 bd->props.power = FB_BLANK_UNBLANK;
127 backlight_update_status(bd);
129 printk("nvidia: Backlight initialized (%s)\n", name);
131 return;
133 error:
134 return;
137 void nvidia_bl_exit(struct nvidia_par *par)
139 struct fb_info *info = pci_get_drvdata(par->pci_dev);
140 struct backlight_device *bd = info->bl_dev;
142 backlight_device_unregister(bd);
143 printk("nvidia: Backlight unloaded\n");