drivers/video/fbdev/aty/radeon_backlight.c

   1 /*
   2  * Backlight code for ATI Radeon based graphic cards
   3  *
   4  * Copyright (c) 2000 Ani Joshi <ajoshi@kernel.crashing.org>
   5  * Copyright (c) 2003 Benjamin Herrenschmidt <benh@kernel.crashing.org>
   6  * Copyright (c) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include "radeonfb.h"
  14 #include <linux/backlight.h>
  15 #include <linux/slab.h>
  16
  17 #ifdef CONFIG_PMAC_BACKLIGHT
  18 #include <asm/backlight.h>
  19 #endif
  20
  21 #define MAX_RADEON_LEVEL 0xFF
  22
  23 struct radeon_bl_privdata {
  24         struct radeonfb_info *rinfo;
  25         uint8_t negative;
  26 };
  27
  28 static int radeon_bl_get_level_brightness(struct radeon_bl_privdata *pdata,
  29                 int level)
  30 {
  31         int rlevel;
  32
  33         /* Get and convert the value */
  34         /* No locking of bl_curve since we read a single value */
  35         rlevel = pdata->rinfo->info->bl_curve[level] *
  36                  FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL;
  37
  38         if (rlevel < 0)
  39                 rlevel = 0;
  40         else if (rlevel > MAX_RADEON_LEVEL)
  41                 rlevel = MAX_RADEON_LEVEL;
  42
  43         if (pdata->negative)
  44                 rlevel = MAX_RADEON_LEVEL - rlevel;
  45
  46         return rlevel;
  47 }
  48
  49 static int radeon_bl_update_status(struct backlight_device *bd)
  50 {
  51         struct radeon_bl_privdata *pdata = bl_get_data(bd);
  52         struct radeonfb_info *rinfo = pdata->rinfo;
  53         u32 lvds_gen_cntl, tmpPixclksCntl;
  54         int level;
  55
  56         if (rinfo->mon1_type != MT_LCD)
  57                 return 0;
  58
  59         /* We turn off the LCD completely instead of just dimming the
  60          * backlight. This provides some greater power saving and the display
  61          * is useless without backlight anyway.
  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         del_timer_sync(&rinfo->lvds_timer);
  70         radeon_engine_idle();
  71
  72         lvds_gen_cntl = INREG(LVDS_GEN_CNTL);
  73         if (level > 0) {
  74                 lvds_gen_cntl &= ~LVDS_DISPLAY_DIS;
  75                 if (!(lvds_gen_cntl & LVDS_BLON) || !(lvds_gen_cntl & LVDS_ON)) {
  76                         lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_DIGON);
  77                         lvds_gen_cntl |= LVDS_BLON | LVDS_EN;
  78                         OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
  79                         lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
  80                         lvds_gen_cntl |=
  81                                 (radeon_bl_get_level_brightness(pdata, level) <<
  82                                  LVDS_BL_MOD_LEVEL_SHIFT);
  83                         lvds_gen_cntl |= LVDS_ON;
  84                         lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_BL_MOD_EN);
  85                         rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
  86                         mod_timer(&rinfo->lvds_timer,
  87                                   jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
  88                 } else {
  89                         lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
  90                         lvds_gen_cntl |=
  91                                 (radeon_bl_get_level_brightness(pdata, level) <<
  92                                  LVDS_BL_MOD_LEVEL_SHIFT);
  93                         OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
  94                 }
  95                 rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
  96                 rinfo->init_state.lvds_gen_cntl |= rinfo->pending_lvds_gen_cntl
  97                         & LVDS_STATE_MASK;
  98         } else {
  99                 /* Asic bug, when turning off LVDS_ON, we have to make sure
 100                    RADEON_PIXCLK_LVDS_ALWAYS_ON bit is off
 101                 */
 102                 tmpPixclksCntl = INPLL(PIXCLKS_CNTL);
 103                 if (rinfo->is_mobility || rinfo->is_IGP)
 104                         OUTPLLP(PIXCLKS_CNTL, 0, ~PIXCLK_LVDS_ALWAYS_ONb);
 105                 lvds_gen_cntl &= ~(LVDS_BL_MOD_LEVEL_MASK | LVDS_BL_MOD_EN);
 106                 lvds_gen_cntl |= (radeon_bl_get_level_brightness(pdata, 0) <<
 107                                   LVDS_BL_MOD_LEVEL_SHIFT);
 108                 lvds_gen_cntl |= LVDS_DISPLAY_DIS;
 109                 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
 110                 udelay(100);
 111                 lvds_gen_cntl &= ~(LVDS_ON | LVDS_EN);
 112                 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
 113                 lvds_gen_cntl &= ~(LVDS_DIGON);
 114                 rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
 115                 mod_timer(&rinfo->lvds_timer,
 116                           jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
 117                 if (rinfo->is_mobility || rinfo->is_IGP)
 118                         OUTPLL(PIXCLKS_CNTL, tmpPixclksCntl);
 119         }
 120         rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
 121         rinfo->init_state.lvds_gen_cntl |= (lvds_gen_cntl & LVDS_STATE_MASK);
 122
 123         return 0;
 124 }
 125
 126 static const struct backlight_ops radeon_bl_data = {
 127         .update_status  = radeon_bl_update_status,
 128 };
 129
 130 void radeonfb_bl_init(struct radeonfb_info *rinfo)
 131 {
 132         struct backlight_properties props;
 133         struct backlight_device *bd;
 134         struct radeon_bl_privdata *pdata;
 135         char name[12];
 136
 137         if (rinfo->mon1_type != MT_LCD)
 138                 return;
 139
 140 #ifdef CONFIG_PMAC_BACKLIGHT
 141         if (!pmac_has_backlight_type("ati") &&
 142             !pmac_has_backlight_type("mnca"))
 143                 return;
 144 #endif
 145
 146         pdata = kmalloc(sizeof(struct radeon_bl_privdata), GFP_KERNEL);
 147         if (!pdata) {
 148                 printk("radeonfb: Memory allocation failed\n");
 149                 goto error;
 150         }
 151
 152         snprintf(name, sizeof(name), "radeonbl%d", rinfo->info->node);
 153
 154         memset(&props, 0, sizeof(struct backlight_properties));
 155         props.type = BACKLIGHT_RAW;
 156         props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
 157         bd = backlight_device_register(name, rinfo->info->dev, pdata,
 158                                        &radeon_bl_data, &props);
 159         if (IS_ERR(bd)) {
 160                 rinfo->info->bl_dev = NULL;
 161                 printk("radeonfb: Backlight registration failed\n");
 162                 goto error;
 163         }
 164
 165         pdata->rinfo = rinfo;
 166
 167         /* Pardon me for that hack... maybe some day we can figure out in what
 168          * direction backlight should work on a given panel?
 169          */
 170         pdata->negative =
 171                 (rinfo->family != CHIP_FAMILY_RV200 &&
 172                  rinfo->family != CHIP_FAMILY_RV250 &&
 173                  rinfo->family != CHIP_FAMILY_RV280 &&
 174                  rinfo->family != CHIP_FAMILY_RV350);
 175
 176 #ifdef CONFIG_PMAC_BACKLIGHT
 177         pdata->negative = pdata->negative ||
 178                 of_machine_is_compatible("PowerBook4,3") ||
 179                 of_machine_is_compatible("PowerBook6,3") ||
 180                 of_machine_is_compatible("PowerBook6,5");
 181 #endif
 182
 183         rinfo->info->bl_dev = bd;
 184         fb_bl_default_curve(rinfo->info, 0,
 185                  63 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL,
 186                 217 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL);
 187
 188         bd->props.brightness = bd->props.max_brightness;
 189         bd->props.power = FB_BLANK_UNBLANK;
 190         backlight_update_status(bd);
 191
 192         printk("radeonfb: Backlight initialized (%s)\n", name);
 193
 194         return;
 195
 196 error:
 197         kfree(pdata);
 198         return;
 199 }
 200
 201 void radeonfb_bl_exit(struct radeonfb_info *rinfo)
 202 {
 203         struct backlight_device *bd = rinfo->info->bl_dev;
 204
 205         if (bd) {
 206                 struct radeon_bl_privdata *pdata;
 207
 208                 pdata = bl_get_data(bd);
 209                 backlight_device_unregister(bd);
 210                 kfree(pdata);
 211                 rinfo->info->bl_dev = NULL;
 212
 213                 printk("radeonfb: Backlight unloaded\n");
 214         }
 215 }