drivers/macintosh/via-pmu-backlight.c

   1 /*
   2  * Backlight code for via-pmu
   3  *
   4  * Copyright (C) 1998 Paul Mackerras and Fabio Riccardi.
   5  * Copyright (C) 2001-2002 Benjamin Herrenschmidt
   6  * Copyright (C) 2006      Michael Hanselmann <linux-kernel@hansmi.ch>
   7  *
   8  */
   9
  10 #include <asm/ptrace.h>
  11 #include <linux/adb.h>
  12 #include <linux/pmu.h>
  13 #include <asm/backlight.h>
  14 #include <asm/prom.h>
  15
  16 #define MAX_PMU_LEVEL 0xFF
  17
  18 static struct backlight_ops pmu_backlight_data;
  19 static DEFINE_SPINLOCK(pmu_backlight_lock);
  20 <<<<<<< HEAD:drivers/macintosh/via-pmu-backlight.c
  21 static int sleeping;
  22 =======
  23 static int sleeping, uses_pmu_bl;
  24 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:drivers/macintosh/via-pmu-backlight.c
  25 static u8 bl_curve[FB_BACKLIGHT_LEVELS];
  26
  27 static void pmu_backlight_init_curve(u8 off, u8 min, u8 max)
  28 {
  29         int i, flat, count, range = (max - min);
  30
  31         bl_curve[0] = off;
  32
  33         for (flat = 1; flat < (FB_BACKLIGHT_LEVELS / 16); ++flat)
  34                 bl_curve[flat] = min;
  35
  36         count = FB_BACKLIGHT_LEVELS * 15 / 16;
  37         for (i = 0; i < count; ++i)
  38                 bl_curve[flat + i] = min + (range * (i + 1) / count);
  39 }
  40
  41 static int pmu_backlight_curve_lookup(int value)
  42 {
  43         int level = (FB_BACKLIGHT_LEVELS - 1);
  44         int i, max = 0;
  45
  46         /* Look for biggest value */
  47         for (i = 0; i < FB_BACKLIGHT_LEVELS; i++)
  48                 max = max((int)bl_curve[i], max);
  49
  50         /* Look for nearest value */
  51         for (i = 0; i < FB_BACKLIGHT_LEVELS; i++) {
  52                 int diff = abs(bl_curve[i] - value);
  53                 if (diff < max) {
  54                         max = diff;
  55                         level = i;
  56                 }
  57         }
  58         return level;
  59 }
  60
  61 static int pmu_backlight_get_level_brightness(int level)
  62 {
  63         int pmulevel;
  64
  65         /* Get and convert the value */
  66         pmulevel = bl_curve[level] * FB_BACKLIGHT_MAX / MAX_PMU_LEVEL;
  67         if (pmulevel < 0)
  68                 pmulevel = 0;
  69         else if (pmulevel > MAX_PMU_LEVEL)
  70                 pmulevel = MAX_PMU_LEVEL;
  71
  72         return pmulevel;
  73 }
  74
  75 static int __pmu_backlight_update_status(struct backlight_device *bd)
  76 {
  77         struct adb_request req;
  78         int level = bd->props.brightness;
  79
  80
  81         if (bd->props.power != FB_BLANK_UNBLANK ||
  82             bd->props.fb_blank != FB_BLANK_UNBLANK)
  83                 level = 0;
  84
  85         if (level > 0) {
  86                 int pmulevel = pmu_backlight_get_level_brightness(level);
  87
  88                 pmu_request(&req, NULL, 2, PMU_BACKLIGHT_BRIGHT, pmulevel);
  89                 pmu_wait_complete(&req);
  90
  91                 pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
  92                         PMU_POW_BACKLIGHT | PMU_POW_ON);
  93                 pmu_wait_complete(&req);
  94         } else {
  95                 pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
  96                         PMU_POW_BACKLIGHT | PMU_POW_OFF);
  97                 pmu_wait_complete(&req);
  98         }
  99
 100         return 0;
 101 }
 102
 103 static int pmu_backlight_update_status(struct backlight_device *bd)
 104 {
 105         unsigned long flags;
 106         int rc = 0;
 107
 108         spin_lock_irqsave(&pmu_backlight_lock, flags);
 109         /* Don't update brightness when sleeping */
 110         if (!sleeping)
 111                 rc = __pmu_backlight_update_status(bd);
 112         spin_unlock_irqrestore(&pmu_backlight_lock, flags);
 113         return rc;
 114 }
 115
 116
 117 static int pmu_backlight_get_brightness(struct backlight_device *bd)
 118 {
 119         return bd->props.brightness;
 120 }
 121
 122 static struct backlight_ops pmu_backlight_data = {
 123         .get_brightness = pmu_backlight_get_brightness,
 124         .update_status  = pmu_backlight_update_status,
 125
 126 };
 127
 128 #ifdef CONFIG_PM
 129 void pmu_backlight_set_sleep(int sleep)
 130 {
 131         unsigned long flags;
 132
 133         spin_lock_irqsave(&pmu_backlight_lock, flags);
 134         sleeping = sleep;
 135 <<<<<<< HEAD:drivers/macintosh/via-pmu-backlight.c
 136         if (pmac_backlight) {
 137 =======
 138         if (pmac_backlight && uses_pmu_bl) {
 139 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:drivers/macintosh/via-pmu-backlight.c
 140                 if (sleep) {
 141                         struct adb_request req;
 142
 143                         pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
 144                                     PMU_POW_BACKLIGHT | PMU_POW_OFF);
 145                         pmu_wait_complete(&req);
 146                 } else
 147                         __pmu_backlight_update_status(pmac_backlight);
 148         }
 149         spin_unlock_irqrestore(&pmu_backlight_lock, flags);
 150 }
 151 #endif /* CONFIG_PM */
 152
 153 void __init pmu_backlight_init()
 154 {
 155         struct backlight_device *bd;
 156         char name[10];
 157         int level, autosave;
 158
 159         /* Special case for the old PowerBook since I can't test on it */
 160         autosave =
 161                 machine_is_compatible("AAPL,3400/2400") ||
 162                 machine_is_compatible("AAPL,3500");
 163
 164         if (!autosave &&
 165             !pmac_has_backlight_type("pmu") &&
 166             !machine_is_compatible("AAPL,PowerBook1998") &&
 167             !machine_is_compatible("PowerBook1,1"))
 168                 return;
 169
 170         snprintf(name, sizeof(name), "pmubl");
 171
 172         bd = backlight_device_register(name, NULL, NULL, &pmu_backlight_data);
 173         if (IS_ERR(bd)) {
 174                 printk(KERN_ERR "PMU Backlight registration failed\n");
 175                 return;
 176         }
 177 <<<<<<< HEAD:drivers/macintosh/via-pmu-backlight.c
 178 =======
 179         uses_pmu_bl = 1;
 180 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:drivers/macintosh/via-pmu-backlight.c
 181         bd->props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
 182         pmu_backlight_init_curve(0x7F, 0x46, 0x0E);
 183
 184         level = bd->props.max_brightness;
 185
 186         if (autosave) {
 187                 /* read autosaved value if available */
 188                 struct adb_request req;
 189                 pmu_request(&req, NULL, 2, 0xd9, 0);
 190                 pmu_wait_complete(&req);
 191
 192                 level = pmu_backlight_curve_lookup(
 193                                 (req.reply[0] >> 4) *
 194                                 bd->props.max_brightness / 15);
 195         }
 196
 197         bd->props.brightness = level;
 198         bd->props.power = FB_BLANK_UNBLANK;
 199         backlight_update_status(bd);
 200
 201         printk(KERN_INFO "PMU Backlight initialized (%s)\n", name);
 202 }