1 /* 2 * Backlight code for nVidia based graphic cards 3 * 4 * Copyright 2004 Antonino Daplas <adaplas@pol.net> 5 * Copyright (c) 2006 Michael Hanselmann <linux-kernel@hansmi.ch> 6 * 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. 10 */ 11 12 #include <linux/backlight.h> 13 #include <linux/fb.h> 14 #include <linux/pci.h> 15 16 #ifdef CONFIG_PMAC_BACKLIGHT 17 #include <asm/backlight.h> 18 #endif 19 20 #include "nv_local.h" 21 #include "nv_type.h" 22 #include "nv_proto.h" 23 24 /* We do not have any information about which values are allowed, thus 25 * we used safe values. 26 */ 27 #define MIN_LEVEL 0x158 28 #define MAX_LEVEL 0x534 29 #define LEVEL_STEP ((MAX_LEVEL - MIN_LEVEL) / FB_BACKLIGHT_MAX) 30 31 static int nvidia_bl_get_level_brightness(struct nvidia_par *par, 32 int level) 33 { 34 struct fb_info *info = pci_get_drvdata(par->pci_dev); 35 int nlevel; 36 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; 40 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; 47 48 return nlevel; 49 } 50 51 static int nvidia_bl_update_status(struct backlight_device *bd) 52 { 53 struct nvidia_par *par = bl_get_data(bd); 54 u32 tmp_pcrt, tmp_pmc, fpcontrol; 55 int level; 56 57 if (!par->FlatPanel) 58 return 0; 59 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; 65 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; 69 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; 77 78 NV_WR32(par->PCRTC0, 0x081C, tmp_pcrt); 79 NV_WR32(par->PMC, 0x10F0, tmp_pmc); 80 NV_WR32(par->PRAMDAC, 0x848, fpcontrol); 81 82 return 0; 83 } 84 85 static const struct backlight_ops nvidia_bl_ops = { 86 .update_status = nvidia_bl_update_status, 87 }; 88 89 void nvidia_bl_init(struct nvidia_par *par) 90 { 91 struct backlight_properties props; 92 struct fb_info *info = pci_get_drvdata(par->pci_dev); 93 struct backlight_device *bd; 94 char name[12]; 95 96 if (!par->FlatPanel) 97 return; 98 99 #ifdef CONFIG_PMAC_BACKLIGHT 100 if (!machine_is(powermac) || 101 !pmac_has_backlight_type("mnca")) 102 return; 103 #endif 104 105 snprintf(name, sizeof(name), "nvidiabl%d", info->node); 106 107 memset(&props, 0, sizeof(struct backlight_properties)); 108 props.type = BACKLIGHT_RAW; 109 props.max_brightness = FB_BACKLIGHT_LEVELS - 1; 110 bd = backlight_device_register(name, info->dev, par, &nvidia_bl_ops, 111 &props); 112 if (IS_ERR(bd)) { 113 info->bl_dev = NULL; 114 printk(KERN_WARNING "nvidia: Backlight registration failed\n"); 115 goto error; 116 } 117 118 info->bl_dev = bd; 119 fb_bl_default_curve(info, 0, 120 0x158 * FB_BACKLIGHT_MAX / MAX_LEVEL, 121 0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL); 122 123 bd->props.brightness = bd->props.max_brightness; 124 bd->props.power = FB_BLANK_UNBLANK; 125 backlight_update_status(bd); 126 127 printk("nvidia: Backlight initialized (%s)\n", name); 128 129 return; 130 131 error: 132 return; 133 } 134 135 void nvidia_bl_exit(struct nvidia_par *par) 136 { 137 struct fb_info *info = pci_get_drvdata(par->pci_dev); 138 struct backlight_device *bd = info->bl_dev; 139 140 backlight_device_unregister(bd); 141 printk("nvidia: Backlight unloaded\n"); 142 } 143