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         level = backlight_get_brightness(bd);
  61
  62         del_timer_sync(&rinfo->lvds_timer);
  63         radeon_engine_idle();
  64
  65         lvds_gen_cntl = INREG(LVDS_GEN_CNTL);
  66         if (level > 0) {
  67                 lvds_gen_cntl &= ~LVDS_DISPLAY_DIS;
  68                 if (!(lvds_gen_cntl & LVDS_BLON) || !(lvds_gen_cntl & LVDS_ON)) {
  69                         lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_DIGON);
  70                         lvds_gen_cntl |= LVDS_BLON | LVDS_EN;
  71                         OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
  72                         lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
  73                         lvds_gen_cntl |=
  74                                 (radeon_bl_get_level_brightness(pdata, level) <<
  75                                  LVDS_BL_MOD_LEVEL_SHIFT);
  76                         lvds_gen_cntl |= LVDS_ON;
  77                         lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_BL_MOD_EN);
  78                         rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
  79                         mod_timer(&rinfo->lvds_timer,
  80                                   jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
  81                 } else {
  82                         lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
  83                         lvds_gen_cntl |=
  84                                 (radeon_bl_get_level_brightness(pdata, level) <<
  85                                  LVDS_BL_MOD_LEVEL_SHIFT);
  86                         OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
  87                 }
  88                 rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
  89                 rinfo->init_state.lvds_gen_cntl |= rinfo->pending_lvds_gen_cntl
  90                         & LVDS_STATE_MASK;
  91         } else {
  92                 /* Asic bug, when turning off LVDS_ON, we have to make sure
  93                    RADEON_PIXCLK_LVDS_ALWAYS_ON bit is off
  94                 */
  95                 tmpPixclksCntl = INPLL(PIXCLKS_CNTL);
  96                 if (rinfo->is_mobility || rinfo->is_IGP)
  97                         OUTPLLP(PIXCLKS_CNTL, 0, ~PIXCLK_LVDS_ALWAYS_ONb);
  98                 lvds_gen_cntl &= ~(LVDS_BL_MOD_LEVEL_MASK | LVDS_BL_MOD_EN);
  99                 lvds_gen_cntl |= (radeon_bl_get_level_brightness(pdata, 0) <<
 100                                   LVDS_BL_MOD_LEVEL_SHIFT);
 101                 lvds_gen_cntl |= LVDS_DISPLAY_DIS;
 102                 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
 103                 udelay(100);
 104                 lvds_gen_cntl &= ~(LVDS_ON | LVDS_EN);
 105                 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
 106                 lvds_gen_cntl &= ~(LVDS_DIGON);
 107                 rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
 108                 mod_timer(&rinfo->lvds_timer,
 109                           jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
 110                 if (rinfo->is_mobility || rinfo->is_IGP)
 111                         OUTPLL(PIXCLKS_CNTL, tmpPixclksCntl);
 112         }
 113         rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
 114         rinfo->init_state.lvds_gen_cntl |= (lvds_gen_cntl & LVDS_STATE_MASK);
 115
 116         return 0;
 117 }
 118
 119 static const struct backlight_ops radeon_bl_data = {
 120         .update_status  = radeon_bl_update_status,
 121 };
 122
 123 void radeonfb_bl_init(struct radeonfb_info *rinfo)
 124 {
 125         struct backlight_properties props;
 126         struct backlight_device *bd;
 127         struct radeon_bl_privdata *pdata;
 128         char name[12];
 129
 130         if (rinfo->mon1_type != MT_LCD)
 131                 return;
 132
 133 #ifdef CONFIG_PMAC_BACKLIGHT
 134         if (!pmac_has_backlight_type("ati") &&
 135             !pmac_has_backlight_type("mnca"))
 136                 return;
 137 #endif
 138
 139         pdata = kmalloc(sizeof(struct radeon_bl_privdata), GFP_KERNEL);
 140         if (!pdata) {
 141                 printk("radeonfb: Memory allocation failed\n");
 142                 goto error;
 143         }
 144
 145         snprintf(name, sizeof(name), "radeonbl%d", rinfo->info->node);
 146
 147         memset(&props, 0, sizeof(struct backlight_properties));
 148         props.type = BACKLIGHT_RAW;
 149         props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
 150         bd = backlight_device_register(name, rinfo->info->device, pdata,
 151                                        &radeon_bl_data, &props);
 152         if (IS_ERR(bd)) {
 153                 rinfo->info->bl_dev = NULL;
 154                 printk("radeonfb: Backlight registration failed\n");
 155                 goto error;
 156         }
 157
 158         pdata->rinfo = rinfo;
 159
 160         /* Pardon me for that hack... maybe some day we can figure out in what
 161          * direction backlight should work on a given panel?
 162          */
 163         pdata->negative =
 164                 (rinfo->family != CHIP_FAMILY_RV200 &&
 165                  rinfo->family != CHIP_FAMILY_RV250 &&
 166                  rinfo->family != CHIP_FAMILY_RV280 &&
 167                  rinfo->family != CHIP_FAMILY_RV350);
 168
 169 #ifdef CONFIG_PMAC_BACKLIGHT
 170         pdata->negative = pdata->negative ||
 171                 of_machine_is_compatible("PowerBook4,3") ||
 172                 of_machine_is_compatible("PowerBook6,3") ||
 173                 of_machine_is_compatible("PowerBook6,5");
 174 #endif
 175
 176         rinfo->info->bl_dev = bd;
 177         fb_bl_default_curve(rinfo->info, 0,
 178                  63 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL,
 179                 217 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL);
 180
 181         bd->props.brightness = bd->props.max_brightness;
 182         bd->props.power = FB_BLANK_UNBLANK;
 183         backlight_update_status(bd);
 184
 185         printk("radeonfb: Backlight initialized (%s)\n", name);
 186
 187         return;
 188
 189 error:
 190         kfree(pdata);
 191         return;
 192 }
 193
 194 void radeonfb_bl_exit(struct radeonfb_info *rinfo)
 195 {
 196         struct backlight_device *bd = rinfo->info->bl_dev;
 197
 198         if (bd) {
 199                 struct radeon_bl_privdata *pdata;
 200
 201                 pdata = bl_get_data(bd);
 202                 backlight_device_unregister(bd);
 203                 kfree(pdata);
 204                 rinfo->info->bl_dev = NULL;
 205
 206                 printk("radeonfb: Backlight unloaded\n");
 207         }
 208 }