drivers/video/fbdev/aty/radeon_backlight.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Backlight code for ATI Radeon based graphic cards
   4  *
   5  * Copyright (c) 2000 Ani Joshi <ajoshi@kernel.crashing.org>
   6  * Copyright (c) 2003 Benjamin Herrenschmidt <benh@kernel.crashing.org>
   7  * Copyright (c) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
   8  */
   9
  10 #include "radeonfb.h"
  11 #include <linux/backlight.h>
  12 #include <linux/slab.h>
  13
  14 #ifdef CONFIG_PMAC_BACKLIGHT
  15 #include <asm/backlight.h>
  16 #endif
  17
  18 #define MAX_RADEON_LEVEL 0xFF
  19
  20 struct radeon_bl_privdata {
  21         struct radeonfb_info *rinfo;
  22         uint8_t negative;
  23 };
  24
  25 static int radeon_bl_get_level_brightness(struct radeon_bl_privdata *pdata,
  26                 int level)
  27 {
  28         int rlevel;
  29
  30         /* Get and convert the value */
  31         /* No locking of bl_curve since we read a single value */
  32         rlevel = pdata->rinfo->info->bl_curve[level] *
  33                  FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL;
  34
  35         if (rlevel < 0)
  36                 rlevel = 0;
  37         else if (rlevel > MAX_RADEON_LEVEL)
  38                 rlevel = MAX_RADEON_LEVEL;
  39
  40         if (pdata->negative)
  41                 rlevel = MAX_RADEON_LEVEL - rlevel;
  42
  43         return rlevel;
  44 }
  45
  46 static int radeon_bl_update_status(struct backlight_device *bd)
  47 {
  48         struct radeon_bl_privdata *pdata = bl_get_data(bd);
  49         struct radeonfb_info *rinfo = pdata->rinfo;
  50         u32 lvds_gen_cntl, tmpPixclksCntl;
  51         int level;
  52
  53         if (rinfo->mon1_type != MT_LCD)
  54                 return 0;
  55
  56         /* We turn off the LCD completely instead of just dimming the
  57          * backlight. This provides some greater power saving and the display
  58          * is useless without backlight anyway.
  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         del_timer_sync(&rinfo->lvds_timer);
  67         radeon_engine_idle();
  68
  69         lvds_gen_cntl = INREG(LVDS_GEN_CNTL);
  70         if (level > 0) {
  71                 lvds_gen_cntl &= ~LVDS_DISPLAY_DIS;
  72                 if (!(lvds_gen_cntl & LVDS_BLON) || !(lvds_gen_cntl & LVDS_ON)) {
  73                         lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_DIGON);
  74                         lvds_gen_cntl |= LVDS_BLON | LVDS_EN;
  75                         OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
  76                         lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
  77                         lvds_gen_cntl |=
  78                                 (radeon_bl_get_level_brightness(pdata, level) <<
  79                                  LVDS_BL_MOD_LEVEL_SHIFT);
  80                         lvds_gen_cntl |= LVDS_ON;
  81                         lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_BL_MOD_EN);
  82                         rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
  83                         mod_timer(&rinfo->lvds_timer,
  84                                   jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
  85                 } else {
  86                         lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
  87                         lvds_gen_cntl |=
  88                                 (radeon_bl_get_level_brightness(pdata, level) <<
  89                                  LVDS_BL_MOD_LEVEL_SHIFT);
  90                         OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
  91                 }
  92                 rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
  93                 rinfo->init_state.lvds_gen_cntl |= rinfo->pending_lvds_gen_cntl
  94                         & LVDS_STATE_MASK;
  95         } else {
  96                 /* Asic bug, when turning off LVDS_ON, we have to make sure
  97                    RADEON_PIXCLK_LVDS_ALWAYS_ON bit is off
  98                 */
  99                 tmpPixclksCntl = INPLL(PIXCLKS_CNTL);
 100                 if (rinfo->is_mobility || rinfo->is_IGP)
 101                         OUTPLLP(PIXCLKS_CNTL, 0, ~PIXCLK_LVDS_ALWAYS_ONb);
 102                 lvds_gen_cntl &= ~(LVDS_BL_MOD_LEVEL_MASK | LVDS_BL_MOD_EN);
 103                 lvds_gen_cntl |= (radeon_bl_get_level_brightness(pdata, 0) <<
 104                                   LVDS_BL_MOD_LEVEL_SHIFT);
 105                 lvds_gen_cntl |= LVDS_DISPLAY_DIS;
 106                 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
 107                 udelay(100);
 108                 lvds_gen_cntl &= ~(LVDS_ON | LVDS_EN);
 109                 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
 110                 lvds_gen_cntl &= ~(LVDS_DIGON);
 111                 rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
 112                 mod_timer(&rinfo->lvds_timer,
 113                           jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
 114                 if (rinfo->is_mobility || rinfo->is_IGP)
 115                         OUTPLL(PIXCLKS_CNTL, tmpPixclksCntl);
 116         }
 117         rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
 118         rinfo->init_state.lvds_gen_cntl |= (lvds_gen_cntl & LVDS_STATE_MASK);
 119
 120         return 0;
 121 }
 122
 123 static const struct backlight_ops radeon_bl_data = {
 124         .update_status  = radeon_bl_update_status,
 125 };
 126
 127 void radeonfb_bl_init(struct radeonfb_info *rinfo)
 128 {
 129         struct backlight_properties props;
 130         struct backlight_device *bd;
 131         struct radeon_bl_privdata *pdata;
 132         char name[12];
 133
 134         if (rinfo->mon1_type != MT_LCD)
 135                 return;
 136
 137 #ifdef CONFIG_PMAC_BACKLIGHT
 138         if (!pmac_has_backlight_type("ati") &&
 139             !pmac_has_backlight_type("mnca"))
 140                 return;
 141 #endif
 142
 143         pdata = kmalloc(sizeof(struct radeon_bl_privdata), GFP_KERNEL);
 144         if (!pdata) {
 145                 printk("radeonfb: Memory allocation failed\n");
 146                 goto error;
 147         }
 148
 149         snprintf(name, sizeof(name), "radeonbl%d", rinfo->info->node);
 150
 151         memset(&props, 0, sizeof(struct backlight_properties));
 152         props.type = BACKLIGHT_RAW;
 153         props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
 154         bd = backlight_device_register(name, rinfo->info->dev, pdata,
 155                                        &radeon_bl_data, &props);
 156         if (IS_ERR(bd)) {
 157                 rinfo->info->bl_dev = NULL;
 158                 printk("radeonfb: Backlight registration failed\n");
 159                 goto error;
 160         }
 161
 162         pdata->rinfo = rinfo;
 163
 164         /* Pardon me for that hack... maybe some day we can figure out in what
 165          * direction backlight should work on a given panel?
 166          */
 167         pdata->negative =
 168                 (rinfo->family != CHIP_FAMILY_RV200 &&
 169                  rinfo->family != CHIP_FAMILY_RV250 &&
 170                  rinfo->family != CHIP_FAMILY_RV280 &&
 171                  rinfo->family != CHIP_FAMILY_RV350);
 172
 173 #ifdef CONFIG_PMAC_BACKLIGHT
 174         pdata->negative = pdata->negative ||
 175                 of_machine_is_compatible("PowerBook4,3") ||
 176                 of_machine_is_compatible("PowerBook6,3") ||
 177                 of_machine_is_compatible("PowerBook6,5");
 178 #endif
 179
 180         rinfo->info->bl_dev = bd;
 181         fb_bl_default_curve(rinfo->info, 0,
 182                  63 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL,
 183                 217 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL);
 184
 185         bd->props.brightness = bd->props.max_brightness;
 186         bd->props.power = FB_BLANK_UNBLANK;
 187         backlight_update_status(bd);
 188
 189         printk("radeonfb: Backlight initialized (%s)\n", name);
 190
 191         return;
 192
 193 error:
 194         kfree(pdata);
 195         return;
 196 }
 197
 198 void radeonfb_bl_exit(struct radeonfb_info *rinfo)
 199 {
 200         struct backlight_device *bd = rinfo->info->bl_dev;
 201
 202         if (bd) {
 203                 struct radeon_bl_privdata *pdata;
 204
 205                 pdata = bl_get_data(bd);
 206                 backlight_device_unregister(bd);
 207                 kfree(pdata);
 208                 rinfo->info->bl_dev = NULL;
 209
 210                 printk("radeonfb: Backlight unloaded\n");
 211         }
 212 }