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>
14 #include <linux/pci.h>
19 /* We do not have any information about which values are allowed, thus
20 * we used safe values.
22 #define MIN_LEVEL 0x158
23 #define MAX_LEVEL 0x534
24 #define LEVEL_STEP ((MAX_LEVEL - MIN_LEVEL) / FB_BACKLIGHT_MAX)
26 static int nvidia_bl_get_level_brightness(struct nvidia_par *par,
29 struct fb_info *info = pci_get_drvdata(par->pci_dev);
32 /* Get and convert the value */
33 /* No locking of bl_curve since we read a single value */
34 nlevel = MIN_LEVEL + info->bl_curve[level] * LEVEL_STEP;
38 else if (nlevel < MIN_LEVEL)
40 else if (nlevel > MAX_LEVEL)
46 static int nvidia_bl_update_status(struct backlight_device *bd)
48 struct nvidia_par *par = class_get_devdata(&bd->class_dev);
49 u32 tmp_pcrt, tmp_pmc, fpcontrol;
55 if (bd->props.power != FB_BLANK_UNBLANK ||
56 bd->props.fb_blank != FB_BLANK_UNBLANK)
59 level = bd->props.brightness;
61 tmp_pmc = NV_RD32(par->PMC, 0x10F0) & 0x0000FFFF;
62 tmp_pcrt = NV_RD32(par->PCRTC0, 0x081C) & 0xFFFFFFFC;
63 fpcontrol = NV_RD32(par->PRAMDAC, 0x0848) & 0xCFFFFFCC;
67 tmp_pmc |= (1 << 31); /* backlight bit */
68 tmp_pmc |= nvidia_bl_get_level_brightness(par, level) << 16;
69 fpcontrol |= par->fpSyncs;
71 fpcontrol |= 0x20000022;
73 NV_WR32(par->PCRTC0, 0x081C, tmp_pcrt);
74 NV_WR32(par->PMC, 0x10F0, tmp_pmc);
75 NV_WR32(par->PRAMDAC, 0x848, fpcontrol);
80 static int nvidia_bl_get_brightness(struct backlight_device *bd)
82 return bd->props.brightness;
85 static struct backlight_ops nvidia_bl_ops = {
86 .get_brightness = nvidia_bl_get_brightness,
87 .update_status = nvidia_bl_update_status,
90 void nvidia_bl_init(struct nvidia_par *par)
92 struct fb_info *info = pci_get_drvdata(par->pci_dev);
93 struct backlight_device *bd;
99 #ifdef CONFIG_PMAC_BACKLIGHT
100 if (!machine_is(powermac) ||
101 !pmac_has_backlight_type("mnca"))
105 snprintf(name, sizeof(name), "nvidiabl%d", info->node);
107 bd = backlight_device_register(name, info->dev, par, &nvidia_bl_ops);
110 printk(KERN_WARNING "nvidia: Backlight registration failed\n");
115 fb_bl_default_curve(info, 0,
116 0x158 * FB_BACKLIGHT_MAX / MAX_LEVEL,
117 0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL);
119 bd->props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
120 bd->props.brightness = bd->props.max_brightness;
121 bd->props.power = FB_BLANK_UNBLANK;
122 backlight_update_status(bd);
124 printk("nvidia: Backlight initialized (%s)\n", name);
132 void nvidia_bl_exit(struct nvidia_par *par)
134 struct fb_info *info = pci_get_drvdata(par->pci_dev);
135 struct backlight_device *bd = info->bl_dev;
137 backlight_device_unregister(bd);
138 printk("nvidia: Backlight unloaded\n");