File: /usr/src/linux/arch/ppc/kernel/pmac_backlight.c
1 /*
2 * BK Id: SCCS/s.pmac_backlight.c 1.8 09/08/01 15:47:42 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[1] >> 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 }
151