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 #define LEVEL_STEP ((MAX_LEVEL - MIN_LEVEL) / FB_BACKLIGHT_MAX)
  30
  31 static struct backlight_properties nvidia_bl_data;
  32
  33 /* Call with fb_info->bl_mutex held */
  34 static int nvidia_bl_get_level_brightness(struct nvidia_par *par,
  35                 int level)
  36 {
  37         struct fb_info *info = pci_get_drvdata(par->pci_dev);
  38         int nlevel;
  39
  40         /* Get and convert the value */
  41         nlevel = MIN_LEVEL + info->bl_curve[level] * LEVEL_STEP;
  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 /* Call with fb_info->bl_mutex held */
  54 static int __nvidia_bl_update_status(struct backlight_device *bd)
  55 {
  56         struct nvidia_par *par = class_get_devdata(&bd->class_dev);
  57         u32 tmp_pcrt, tmp_pmc, fpcontrol;
  58         int level;
  59
  60         if (!par->FlatPanel)
  61                 return 0;
  62
  63         if (bd->props->power != FB_BLANK_UNBLANK ||
  64             bd->props->fb_blank != FB_BLANK_UNBLANK)
  65                 level = 0;
  66         else
  67                 level = bd->props->brightness;
  68
  69         tmp_pmc = NV_RD32(par->PMC, 0x10F0) & 0x0000FFFF;
  70         tmp_pcrt = NV_RD32(par->PCRTC0, 0x081C) & 0xFFFFFFFC;
  71         fpcontrol = NV_RD32(par->PRAMDAC, 0x0848) & 0xCFFFFFCC;
  72
  73         if (level > 0) {
  74                 tmp_pcrt |= 0x1;
  75                 tmp_pmc |= (1 << 31); /* backlight bit */
  76                 tmp_pmc |= nvidia_bl_get_level_brightness(par, level) << 16;
  77                 fpcontrol |= par->fpSyncs;
  78         } else
  79                 fpcontrol |= 0x20000022;
  80
  81         NV_WR32(par->PCRTC0, 0x081C, tmp_pcrt);
  82         NV_WR32(par->PMC, 0x10F0, tmp_pmc);
  83         NV_WR32(par->PRAMDAC, 0x848, fpcontrol);
  84
  85         return 0;
  86 }
  87
  88 static int nvidia_bl_update_status(struct backlight_device *bd)
  89 {
  90         struct nvidia_par *par = class_get_devdata(&bd->class_dev);
  91         struct fb_info *info = pci_get_drvdata(par->pci_dev);
  92         int ret;
  93
  94         mutex_lock(&info->bl_mutex);
  95         ret = __nvidia_bl_update_status(bd);
  96         mutex_unlock(&info->bl_mutex);
  97
  98         return ret;
  99 }
 100
 101 static int nvidia_bl_get_brightness(struct backlight_device *bd)
 102 {
 103         return bd->props->brightness;
 104 }
 105
 106 static struct backlight_properties nvidia_bl_data = {
 107         .owner          = THIS_MODULE,
 108         .get_brightness = nvidia_bl_get_brightness,
 109         .update_status  = nvidia_bl_update_status,
 110         .max_brightness = (FB_BACKLIGHT_LEVELS - 1),
 111 };
 112
 113 void nvidia_bl_set_power(struct fb_info *info, int power)
 114 {
 115         mutex_lock(&info->bl_mutex);
 116
 117         if (info->bl_dev) {
 118                 down(&info->bl_dev->sem);
 119                 info->bl_dev->props->power = power;
 120                 __nvidia_bl_update_status(info->bl_dev);
 121                 up(&info->bl_dev->sem);
 122         }
 123
 124         mutex_unlock(&info->bl_mutex);
 125 }
 126
 127 void nvidia_bl_init(struct nvidia_par *par)
 128 {
 129         struct fb_info *info = pci_get_drvdata(par->pci_dev);
 130         struct backlight_device *bd;
 131         char name[12];
 132
 133         if (!par->FlatPanel)
 134                 return;
 135
 136 #ifdef CONFIG_PMAC_BACKLIGHT
 137         if (!machine_is(powermac) ||
 138             !pmac_has_backlight_type("mnca"))
 139                 return;
 140 #endif
 141
 142         snprintf(name, sizeof(name), "nvidiabl%d", info->node);
 143
 144         bd = backlight_device_register(name, info->dev, par, &nvidia_bl_data);
 145         if (IS_ERR(bd)) {
 146                 info->bl_dev = NULL;
 147                 printk(KERN_WARNING "nvidia: Backlight registration failed\n");
 148                 goto error;
 149         }
 150
 151         mutex_lock(&info->bl_mutex);
 152         info->bl_dev = bd;
 153         fb_bl_default_curve(info, 0,
 154                 0x158 * FB_BACKLIGHT_MAX / MAX_LEVEL,
 155                 0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL);
 156         mutex_unlock(&info->bl_mutex);
 157
 158         down(&bd->sem);
 159         bd->props->brightness = nvidia_bl_data.max_brightness;
 160         bd->props->power = FB_BLANK_UNBLANK;
 161         bd->props->update_status(bd);
 162         up(&bd->sem);
 163
 164 #ifdef CONFIG_PMAC_BACKLIGHT
 165         mutex_lock(&pmac_backlight_mutex);
 166         if (!pmac_backlight)
 167                 pmac_backlight = bd;
 168         mutex_unlock(&pmac_backlight_mutex);
 169 #endif
 170
 171         printk("nvidia: Backlight initialized (%s)\n", name);
 172
 173         return;
 174
 175 error:
 176         return;
 177 }
 178
 179 void nvidia_bl_exit(struct nvidia_par *par)
 180 {
 181         struct fb_info *info = pci_get_drvdata(par->pci_dev);
 182
 183 #ifdef CONFIG_PMAC_BACKLIGHT
 184         mutex_lock(&pmac_backlight_mutex);
 185 #endif
 186
 187         mutex_lock(&info->bl_mutex);
 188         if (info->bl_dev) {
 189 #ifdef CONFIG_PMAC_BACKLIGHT
 190                 if (pmac_backlight == info->bl_dev)
 191                         pmac_backlight = NULL;
 192 #endif
 193
 194                 backlight_device_unregister(info->bl_dev);
 195
 196                 printk("nvidia: Backlight unloaded\n");
 197         }
 198         mutex_unlock(&info->bl_mutex);
 199
 200 #ifdef CONFIG_PMAC_BACKLIGHT
 201         mutex_unlock(&pmac_backlight_mutex);
 202 #endif
 203 }