drivers/video/nvidia/nv_backlight.c

   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 #include "nv_local.h"
  16 #include "nv_type.h"
  17 #include "nv_proto.h"
  18
  19 #ifdef CONFIG_PMAC_BACKLIGHT
  20 #include <asm/backlight.h>
  21 #include <asm/machdep.h>
  22 #endif
  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
  30 static struct backlight_properties nvidia_bl_data;
  31
  32 static int nvidia_bl_get_level_brightness(struct nvidia_par *par,
  33                 int level)
  34 {
  35         struct fb_info *info = pci_get_drvdata(par->pci_dev);
  36         int nlevel;
  37
  38         /* Get and convert the value */
  39         mutex_lock(&info->bl_mutex);
  40         nlevel = info->bl_curve[level] * FB_BACKLIGHT_MAX / MAX_LEVEL;
  41         mutex_unlock(&info->bl_mutex);
  42
  43         if (nlevel < 0)
  44                 nlevel = 0;
  45         else if (nlevel < MIN_LEVEL)
  46                 nlevel = MIN_LEVEL;
  47         else if (nlevel > MAX_LEVEL)
  48                 nlevel = MAX_LEVEL;
  49
  50         return nlevel;
  51 }
  52
  53 static int nvidia_bl_update_status(struct backlight_device *bd)
  54 {
  55         struct nvidia_par *par = class_get_devdata(&bd->class_dev);
  56         u32 tmp_pcrt, tmp_pmc, fpcontrol;
  57         int level;
  58
  59         if (!par->FlatPanel)
  60                 return 0;
  61
  62         if (bd->props->power != FB_BLANK_UNBLANK ||
  63             bd->props->fb_blank != FB_BLANK_UNBLANK)
  64                 level = 0;
  65         else
  66                 level = bd->props->brightness;
  67
  68         tmp_pmc = NV_RD32(par->PMC, 0x10F0) & 0x0000FFFF;
  69         tmp_pcrt = NV_RD32(par->PCRTC0, 0x081C) & 0xFFFFFFFC;
  70         fpcontrol = NV_RD32(par->PRAMDAC, 0x0848) & 0xCFFFFFCC;
  71
  72         if (level > 0) {
  73                 tmp_pcrt |= 0x1;
  74                 tmp_pmc |= (1 << 31); /* backlight bit */
  75                 tmp_pmc |= nvidia_bl_get_level_brightness(par, level) << 16;
  76                 fpcontrol |= par->fpSyncs;
  77         } else
  78                 fpcontrol |= 0x20000022;
  79
  80         NV_WR32(par->PCRTC0, 0x081C, tmp_pcrt);
  81         NV_WR32(par->PMC, 0x10F0, tmp_pmc);
  82         NV_WR32(par->PRAMDAC, 0x848, fpcontrol);
  83
  84         return 0;
  85 }
  86
  87 static int nvidia_bl_get_brightness(struct backlight_device *bd)
  88 {
  89         return bd->props->brightness;
  90 }
  91
  92 static struct backlight_properties nvidia_bl_data = {
  93         .owner          = THIS_MODULE,
  94         .get_brightness = nvidia_bl_get_brightness,
  95         .update_status  = nvidia_bl_update_status,
  96         .max_brightness = (FB_BACKLIGHT_LEVELS - 1),
  97 };
  98
  99 void nvidia_bl_init(struct nvidia_par *par)
 100 {
 101         struct fb_info *info = pci_get_drvdata(par->pci_dev);
 102         struct backlight_device *bd;
 103         char name[12];
 104
 105         if (!par->FlatPanel)
 106                 return;
 107
 108 #ifdef CONFIG_PMAC_BACKLIGHT
 109         if (!machine_is(powermac) ||
 110             !pmac_has_backlight_type("mnca"))
 111                 return;
 112 #endif
 113
 114         snprintf(name, sizeof(name), "nvidiabl%d", info->node);
 115
 116         bd = backlight_device_register(name, par, &nvidia_bl_data);
 117         if (IS_ERR(bd)) {
 118                 info->bl_dev = NULL;
 119                 printk("nvidia: Backlight registration failed\n");
 120                 goto error;
 121         }
 122
 123         mutex_lock(&info->bl_mutex);
 124         info->bl_dev = bd;
 125         fb_bl_default_curve(info, 0,
 126                 0x158 * FB_BACKLIGHT_MAX / MAX_LEVEL,
 127                 0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL);
 128         mutex_unlock(&info->bl_mutex);
 129
 130         up(&bd->sem);
 131         bd->props->brightness = nvidia_bl_data.max_brightness;
 132         bd->props->power = FB_BLANK_UNBLANK;
 133         bd->props->update_status(bd);
 134         down(&bd->sem);
 135
 136 #ifdef CONFIG_PMAC_BACKLIGHT
 137         mutex_lock(&pmac_backlight_mutex);
 138         if (!pmac_backlight)
 139                 pmac_backlight = bd;
 140         mutex_unlock(&pmac_backlight_mutex);
 141 #endif
 142
 143         printk("nvidia: Backlight initialized (%s)\n", name);
 144
 145         return;
 146
 147 error:
 148         return;
 149 }
 150
 151 void nvidia_bl_exit(struct nvidia_par *par)
 152 {
 153         struct fb_info *info = pci_get_drvdata(par->pci_dev);
 154
 155 #ifdef CONFIG_PMAC_BACKLIGHT
 156         mutex_lock(&pmac_backlight_mutex);
 157 #endif
 158
 159         mutex_lock(&info->bl_mutex);
 160         if (info->bl_dev) {
 161 #ifdef CONFIG_PMAC_BACKLIGHT
 162                 if (pmac_backlight == info->bl_dev)
 163                         pmac_backlight = NULL;
 164 #endif
 165
 166                 backlight_device_unregister(info->bl_dev);
 167
 168                 printk("nvidia: Backlight unloaded\n");
 169         }
 170         mutex_unlock(&info->bl_mutex);
 171
 172 #ifdef CONFIG_PMAC_BACKLIGHT
 173         mutex_unlock(&pmac_backlight_mutex);
 174 #endif
 175 }