arch/ppc/platforms/pmac_backlight.c

   1 /*
   2  * BK Id: SCCS/s.pmac_backlight.c 1.14 08/13/02 21:52:54 paulus
   3  */
   4 /*
   5  * Miscellaneous procedures for dealing with the PowerMac hardware.
   6  * Contains support for the backlight.
   7  *
   8  *   Copyright (C) 2000 Benjamin Herrenschmidt
   9  *
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/kernel.h>
  14 #include <linux/stddef.h>
  15 #include <linux/reboot.h>
  16 #include <linux/nvram.h>
  17 #include <asm/sections.h>
  18 #include <asm/ptrace.h>
  19 #include <asm/io.h>
  20 #include <asm/pgtable.h>
  21 #include <asm/system.h>
  22 #include <asm/prom.h>
  23 #include <asm/machdep.h>
  24 #include <asm/nvram.h>
  25 #include <asm/backlight.h>
  26
  27 #include <linux/adb.h>
  28 #include <linux/pmu.h>
  29
  30 static struct backlight_controller *backlighter = NULL;
  31 static void* backlighter_data = NULL;
  32 static int backlight_autosave = 0;
  33 static int backlight_level = BACKLIGHT_MAX;
  34 static int backlight_enabled = 1;
  35
  36 void __pmac
  37 register_backlight_controller(struct backlight_controller *ctrler, void *data, char *type)
  38 {
  39         struct device_node* bk_node;
  40         char *prop;
  41         int valid = 0;
  42
  43         bk_node = find_devices("backlight");
  44
  45 #ifdef CONFIG_ADB_PMU
  46         /* Special case for the old PowerBook since I can't test on it */
  47         backlight_autosave = machine_is_compatible("AAPL,3400/2400")
  48                 || machine_is_compatible("AAPL,3500");
  49         if ((backlight_autosave
  50              || machine_is_compatible("AAPL,PowerBook1998")
  51              || machine_is_compatible("PowerBook1,1"))
  52             && !strcmp(type, "pmu"))
  53                 valid = 1;
  54 #endif
  55         if (bk_node) {
  56                 prop = get_property(bk_node, "backlight-control", NULL);
  57                 if (prop && !strncmp(prop, type, strlen(type)))
  58                         valid = 1;
  59         }
  60         if (!valid)
  61                 return;
  62         backlighter = ctrler;
  63         backlighter_data = data;
  64
  65         if (bk_node && !backlight_autosave)
  66                 prop = get_property(bk_node, "bklt", NULL);
  67         else
  68                 prop = NULL;
  69         if (prop) {
  70                 backlight_level = ((*prop)+1) >> 1;
  71                 if (backlight_level > BACKLIGHT_MAX)
  72                         backlight_level = BACKLIGHT_MAX;
  73         }
  74
  75 #ifdef CONFIG_ADB_PMU
  76         if (backlight_autosave) {
  77                 struct adb_request req;
  78                 pmu_request(&req, NULL, 2, 0xd9, 0);
  79                 while (!req.complete)
  80                         pmu_poll();
  81                 backlight_level = req.reply[0] >> 4;
  82         }
  83 #endif
  84         if (!backlighter->set_enable(1, backlight_level, data))
  85                 backlight_enabled = 1;
  86
  87         printk(KERN_INFO "Registered \"%s\" backlight controller, level: %d/15\n",
  88                 type, backlight_level);
  89 }
  90
  91 void __pmac
  92 unregister_backlight_controller(struct backlight_controller *ctrler, void *data)
  93 {
  94         /* We keep the current backlight level (for now) */
  95         if (ctrler == backlighter && data == backlighter_data)
  96                 backlighter = NULL;
  97 }
  98
  99 int __pmac
 100 set_backlight_enable(int enable)
 101 {
 102         int rc;
 103
 104         if (!backlighter)
 105                 return -ENODEV;
 106         rc = backlighter->set_enable(enable, backlight_level, backlighter_data);
 107         if (!rc)
 108                 backlight_enabled = enable;
 109         return rc;
 110 }
 111
 112 int __pmac
 113 get_backlight_enable(void)
 114 {
 115         if (!backlighter)
 116                 return -ENODEV;
 117         return backlight_enabled;
 118 }
 119
 120 int __pmac
 121 set_backlight_level(int level)
 122 {
 123         int rc = 0;
 124
 125         if (!backlighter)
 126                 return -ENODEV;
 127         if (level < BACKLIGHT_MIN)
 128                 level = BACKLIGHT_OFF;
 129         if (level > BACKLIGHT_MAX)
 130                 level = BACKLIGHT_MAX;
 131         if (backlight_enabled)
 132                 rc = backlighter->set_level(level, backlighter_data);
 133         if (!rc)
 134                 backlight_level = level;
 135         if (!rc && !backlight_autosave) {
 136                 level <<=1;
 137                 if (level & 0x10)
 138                         level |= 0x01;
 139                 // -- todo: save to property "bklt"
 140         }
 141         return rc;
 142 }
 143
 144 int __pmac
 145 get_backlight_level(void)
 146 {
 147         if (!backlighter)
 148                 return -ENODEV;
 149         return backlight_level;
 150 }