drivers/video/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
  16 #ifdef CONFIG_PMAC_BACKLIGHT
  17 #include <asm/backlight.h>
  18 #endif
  19
  20 #define MAX_RADEON_LEVEL 0xFF
  21
  22 struct radeon_bl_privdata {
  23         struct radeonfb_info *rinfo;
  24         uint8_t negative;
  25 };
  26
  27 static int radeon_bl_get_level_brightness(struct radeon_bl_privdata *pdata,
  28                 int level)
  29 {
  30         int rlevel;
  31
  32         /* Get and convert the value */
  33         /* No locking of bl_curve since we read a single value */
  34         rlevel = pdata->rinfo->info->bl_curve[level] *
  35                  FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL;
  36
  37         if (rlevel < 0)
  38                 rlevel = 0;
  39         else if (rlevel > MAX_RADEON_LEVEL)
  40                 rlevel = MAX_RADEON_LEVEL;
  41
  42         if (pdata->negative)
  43                 rlevel = MAX_RADEON_LEVEL - rlevel;
  44
  45         return rlevel;
  46 }
  47
  48 static int radeon_bl_update_status(struct backlight_device *bd)
  49 {
  50         struct radeon_bl_privdata *pdata = bl_get_data(bd);
  51         struct radeonfb_info *rinfo = pdata->rinfo;
  52         u32 lvds_gen_cntl, tmpPixclksCntl;
  53         int level;
  54
  55         if (rinfo->mon1_type != MT_LCD)
  56                 return 0;
  57
  58         /* We turn off the LCD completely instead of just dimming the
  59          * backlight. This provides some greater power saving and the display
  60          * is useless without backlight anyway.
  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         del_timer_sync(&rinfo->lvds_timer);
  69         radeon_engine_idle();
  70
  71         lvds_gen_cntl = INREG(LVDS_GEN_CNTL);
  72         if (level > 0) {
  73                 lvds_gen_cntl &= ~LVDS_DISPLAY_DIS;
  74                 if (!(lvds_gen_cntl & LVDS_BLON) || !(lvds_gen_cntl & LVDS_ON)) {
  75                         lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_DIGON);
  76                         lvds_gen_cntl |= LVDS_BLON | LVDS_EN;
  77                         OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
  78                         lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
  79                         lvds_gen_cntl |=
  80                                 (radeon_bl_get_level_brightness(pdata, level) <<
  81                                  LVDS_BL_MOD_LEVEL_SHIFT);
  82                         lvds_gen_cntl |= LVDS_ON;
  83                         lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_BL_MOD_EN);
  84                         rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
  85                         mod_timer(&rinfo->lvds_timer,
  86                                   jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
  87                 } else {
  88                         lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
  89                         lvds_gen_cntl |=
  90                                 (radeon_bl_get_level_brightness(pdata, level) <<
  91                                  LVDS_BL_MOD_LEVEL_SHIFT);
  92                         OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
  93                 }
  94                 rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
  95                 rinfo->init_state.lvds_gen_cntl |= rinfo->pending_lvds_gen_cntl
  96                         & LVDS_STATE_MASK;
  97         } else {
  98                 /* Asic bug, when turning off LVDS_ON, we have to make sure
  99                    RADEON_PIXCLK_LVDS_ALWAYS_ON bit is off
 100                 */
 101                 tmpPixclksCntl = INPLL(PIXCLKS_CNTL);
 102                 if (rinfo->is_mobility || rinfo->is_IGP)
 103                         OUTPLLP(PIXCLKS_CNTL, 0, ~PIXCLK_LVDS_ALWAYS_ONb);
 104                 lvds_gen_cntl &= ~(LVDS_BL_MOD_LEVEL_MASK | LVDS_BL_MOD_EN);
 105                 lvds_gen_cntl |= (radeon_bl_get_level_brightness(pdata, 0) <<
 106                                   LVDS_BL_MOD_LEVEL_SHIFT);
 107                 lvds_gen_cntl |= LVDS_DISPLAY_DIS;
 108                 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
 109                 udelay(100);
 110                 lvds_gen_cntl &= ~(LVDS_ON | LVDS_EN);
 111                 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
 112                 lvds_gen_cntl &= ~(LVDS_DIGON);
 113                 rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
 114                 mod_timer(&rinfo->lvds_timer,
 115                           jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
 116                 if (rinfo->is_mobility || rinfo->is_IGP)
 117                         OUTPLL(PIXCLKS_CNTL, tmpPixclksCntl);
 118         }
 119         rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
 120         rinfo->init_state.lvds_gen_cntl |= (lvds_gen_cntl & LVDS_STATE_MASK);
 121
 122         return 0;
 123 }
 124
 125 static int radeon_bl_get_brightness(struct backlight_device *bd)
 126 {
 127         return bd->props.brightness;
 128 }
 129
 130 static struct backlight_ops radeon_bl_data = {
 131         .get_brightness = radeon_bl_get_brightness,
 132         .update_status  = radeon_bl_update_status,
 133 };
 134
 135 void radeonfb_bl_init(struct radeonfb_info *rinfo)
 136 {
 137         struct backlight_properties props;
 138         struct backlight_device *bd;
 139         struct radeon_bl_privdata *pdata;
 140         char name[12];
 141
 142         if (rinfo->mon1_type != MT_LCD)
 143                 return;
 144
 145 #ifdef CONFIG_PMAC_BACKLIGHT
 146         if (!pmac_has_backlight_type("ati") &&
 147             !pmac_has_backlight_type("mnca"))
 148                 return;
 149 #endif
 150
 151         pdata = kmalloc(sizeof(struct radeon_bl_privdata), GFP_KERNEL);
 152         if (!pdata) {
 153                 printk("radeonfb: Memory allocation failed\n");
 154                 goto error;
 155         }
 156
 157         snprintf(name, sizeof(name), "radeonbl%d", rinfo->info->node);
 158
 159         memset(&props, 0, sizeof(struct backlight_properties));
 160         props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
 161         bd = backlight_device_register(name, rinfo->info->dev, pdata,
 162                                        &radeon_bl_data, &props);
 163         if (IS_ERR(bd)) {
 164                 rinfo->info->bl_dev = NULL;
 165                 printk("radeonfb: Backlight registration failed\n");
 166                 goto error;
 167         }
 168
 169         pdata->rinfo = rinfo;
 170
 171         /* Pardon me for that hack... maybe some day we can figure out in what
 172          * direction backlight should work on a given panel?
 173          */
 174         pdata->negative =
 175                 (rinfo->family != CHIP_FAMILY_RV200 &&
 176                  rinfo->family != CHIP_FAMILY_RV250 &&
 177                  rinfo->family != CHIP_FAMILY_RV280 &&
 178                  rinfo->family != CHIP_FAMILY_RV350);
 179
 180 #ifdef CONFIG_PMAC_BACKLIGHT
 181         pdata->negative = pdata->negative ||
 182                 of_machine_is_compatible("PowerBook4,3") ||
 183                 of_machine_is_compatible("PowerBook6,3") ||
 184                 of_machine_is_compatible("PowerBook6,5");
 185 #endif
 186
 187         rinfo->info->bl_dev = bd;
 188         fb_bl_default_curve(rinfo->info, 0,
 189                  63 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL,
 190                 217 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL);
 191
 192         bd->props.brightness = bd->props.max_brightness;
 193         bd->props.power = FB_BLANK_UNBLANK;
 194         backlight_update_status(bd);
 195
 196         printk("radeonfb: Backlight initialized (%s)\n", name);
 197
 198         return;
 199
 200 error:
 201         kfree(pdata);
 202         return;
 203 }
 204
 205 void radeonfb_bl_exit(struct radeonfb_info *rinfo)
 206 {
 207         struct backlight_device *bd = rinfo->info->bl_dev;
 208
 209         if (bd) {
 210                 struct radeon_bl_privdata *pdata;
 211
 212                 pdata = bl_get_data(bd);
 213                 backlight_device_unregister(bd);
 214                 kfree(pdata);
 215                 rinfo->info->bl_dev = NULL;
 216
 217                 printk("radeonfb: Backlight unloaded\n");
 218         }
 219 }