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 struct backlight_properties nvidia_bl_data;
28 static int nvidia_bl_get_level_brightness(struct nvidia_par *par,
31 struct fb_info *info = pci_get_drvdata(par->pci_dev);
34 /* Get and convert the value */
35 /* No locking of bl_curve since we read a single value */
36 nlevel = MIN_LEVEL + info->bl_curve[level] * LEVEL_STEP;
40 else if (nlevel < MIN_LEVEL)
42 else if (nlevel > MAX_LEVEL)
48 static int nvidia_bl_update_status(struct backlight_device *bd)
50 struct nvidia_par *par = class_get_devdata(&bd->class_dev);
51 u32 tmp_pcrt, tmp_pmc, fpcontrol;
57 if (bd->props->power != FB_BLANK_UNBLANK ||
58 bd->props->fb_blank != FB_BLANK_UNBLANK)
61 level = bd->props->brightness;
63 tmp_pmc = NV_RD32(par->PMC, 0x10F0) & 0x0000FFFF;
64 tmp_pcrt = NV_RD32(par->PCRTC0, 0x081C) & 0xFFFFFFFC;
65 fpcontrol = NV_RD32(par->PRAMDAC, 0x0848) & 0xCFFFFFCC;
69 tmp_pmc |= (1 << 31); /* backlight bit */
70 tmp_pmc |= nvidia_bl_get_level_brightness(par, level) << 16;
71 fpcontrol |= par->fpSyncs;
73 fpcontrol |= 0x20000022;
75 NV_WR32(par->PCRTC0, 0x081C, tmp_pcrt);
76 NV_WR32(par->PMC, 0x10F0, tmp_pmc);
77 NV_WR32(par->PRAMDAC, 0x848, fpcontrol);
82 static int nvidia_bl_get_brightness(struct backlight_device *bd)
84 return bd->props->brightness;
87 static struct backlight_properties nvidia_bl_data = {
88 .get_brightness = nvidia_bl_get_brightness,
89 .update_status = nvidia_bl_update_status,
90 .max_brightness = (FB_BACKLIGHT_LEVELS - 1),
93 void nvidia_bl_init(struct nvidia_par *par)
95 struct fb_info *info = pci_get_drvdata(par->pci_dev);
96 struct backlight_device *bd;
102 #ifdef CONFIG_PMAC_BACKLIGHT
103 if (!machine_is(powermac) ||
104 !pmac_has_backlight_type("mnca"))
108 snprintf(name, sizeof(name), "nvidiabl%d", info->node);
110 bd = backlight_device_register(name, info->dev, par, &nvidia_bl_data);
113 printk(KERN_WARNING "nvidia: Backlight registration failed\n");
118 fb_bl_default_curve(info, 0,
119 0x158 * FB_BACKLIGHT_MAX / MAX_LEVEL,
120 0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL);
122 bd->props->brightness = nvidia_bl_data.max_brightness;
123 bd->props->power = FB_BLANK_UNBLANK;
124 backlight_update_status(bd);
126 printk("nvidia: Backlight initialized (%s)\n", name);
134 void nvidia_bl_exit(struct nvidia_par *par)
136 struct fb_info *info = pci_get_drvdata(par->pci_dev);
137 struct backlight_device *bd = info->bl_dev;
139 backlight_device_unregister(bd);
140 printk("nvidia: Backlight unloaded\n");