Commit | Line | Data |
---|---|---|
5474c120 MH |
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 | ||
599a52d1 | 18 | static struct backlight_ops pmu_backlight_data; |
4efd587b | 19 | static DEFINE_SPINLOCK(pmu_backlight_lock); |
4b755999 | 20 | static int sleeping; |
d565dd3b | 21 | static u8 bl_curve[FB_BACKLIGHT_LEVELS]; |
5474c120 | 22 | |
d565dd3b BH |
23 | static void pmu_backlight_init_curve(u8 off, u8 min, u8 max) |
24 | { | |
25 | unsigned int i, flat, count, range = (max - min); | |
26 | ||
27 | bl_curve[0] = off; | |
28 | ||
29 | for (flat = 1; flat < (FB_BACKLIGHT_LEVELS / 16); ++flat) | |
30 | bl_curve[flat] = min; | |
31 | ||
32 | count = FB_BACKLIGHT_LEVELS * 15 / 16; | |
33 | for (i = 0; i < count; ++i) | |
34 | bl_curve[flat + i] = min + (range * (i + 1) / count); | |
35 | } | |
36 | ||
37 | static int pmu_backlight_curve_lookup(int value) | |
38 | { | |
39 | int level = (FB_BACKLIGHT_LEVELS - 1); | |
40 | int i, max = 0; | |
41 | ||
42 | /* Look for biggest value */ | |
43 | for (i = 0; i < FB_BACKLIGHT_LEVELS; i++) | |
44 | max = max((int)bl_curve[i], max); | |
45 | ||
46 | /* Look for nearest value */ | |
47 | for (i = 0; i < FB_BACKLIGHT_LEVELS; i++) { | |
48 | int diff = abs(bl_curve[i] - value); | |
49 | if (diff < max) { | |
50 | max = diff; | |
51 | level = i; | |
52 | } | |
53 | } | |
54 | return level; | |
55 | } | |
56 | ||
57 | static int pmu_backlight_get_level_brightness(int level) | |
5474c120 MH |
58 | { |
59 | int pmulevel; | |
60 | ||
61 | /* Get and convert the value */ | |
d565dd3b | 62 | pmulevel = bl_curve[level] * FB_BACKLIGHT_MAX / MAX_PMU_LEVEL; |
5474c120 MH |
63 | if (pmulevel < 0) |
64 | pmulevel = 0; | |
65 | else if (pmulevel > MAX_PMU_LEVEL) | |
66 | pmulevel = MAX_PMU_LEVEL; | |
67 | ||
68 | return pmulevel; | |
69 | } | |
70 | ||
71 | static int pmu_backlight_update_status(struct backlight_device *bd) | |
72 | { | |
5474c120 | 73 | struct adb_request req; |
4b755999 | 74 | unsigned long flags; |
599a52d1 | 75 | int level = bd->props.brightness; |
5474c120 | 76 | |
4b755999 MH |
77 | spin_lock_irqsave(&pmu_backlight_lock, flags); |
78 | ||
79 | /* Don't update brightness when sleeping */ | |
80 | if (sleeping) | |
81 | goto out; | |
5474c120 | 82 | |
599a52d1 RP |
83 | if (bd->props.power != FB_BLANK_UNBLANK || |
84 | bd->props.fb_blank != FB_BLANK_UNBLANK) | |
5474c120 MH |
85 | level = 0; |
86 | ||
4b755999 | 87 | if (level > 0) { |
d565dd3b | 88 | int pmulevel = pmu_backlight_get_level_brightness(level); |
5474c120 | 89 | |
4b755999 MH |
90 | pmu_request(&req, NULL, 2, PMU_BACKLIGHT_BRIGHT, pmulevel); |
91 | pmu_wait_complete(&req); | |
5474c120 | 92 | |
4b755999 MH |
93 | pmu_request(&req, NULL, 2, PMU_POWER_CTRL, |
94 | PMU_POW_BACKLIGHT | PMU_POW_ON); | |
95 | pmu_wait_complete(&req); | |
96 | } else { | |
97 | pmu_request(&req, NULL, 2, PMU_POWER_CTRL, | |
98 | PMU_POW_BACKLIGHT | PMU_POW_OFF); | |
99 | pmu_wait_complete(&req); | |
100 | } | |
101 | ||
102 | out: | |
103 | spin_unlock_irqrestore(&pmu_backlight_lock, flags); | |
5474c120 MH |
104 | |
105 | return 0; | |
106 | } | |
107 | ||
108 | static int pmu_backlight_get_brightness(struct backlight_device *bd) | |
109 | { | |
599a52d1 | 110 | return bd->props.brightness; |
5474c120 MH |
111 | } |
112 | ||
599a52d1 | 113 | static struct backlight_ops pmu_backlight_data = { |
5474c120 MH |
114 | .get_brightness = pmu_backlight_get_brightness, |
115 | .update_status = pmu_backlight_update_status, | |
599a52d1 | 116 | |
5474c120 MH |
117 | }; |
118 | ||
4b755999 | 119 | #ifdef CONFIG_PM |
d565dd3b | 120 | void pmu_backlight_set_sleep(int sleep) |
4b755999 MH |
121 | { |
122 | unsigned long flags; | |
123 | ||
124 | spin_lock_irqsave(&pmu_backlight_lock, flags); | |
d565dd3b | 125 | sleeping = sleep; |
4b755999 | 126 | spin_unlock_irqrestore(&pmu_backlight_lock, flags); |
4b755999 | 127 | } |
d565dd3b | 128 | #endif /* CONFIG_PM */ |
4b755999 MH |
129 | |
130 | void __init pmu_backlight_init() | |
5474c120 MH |
131 | { |
132 | struct backlight_device *bd; | |
5474c120 MH |
133 | char name[10]; |
134 | int level, autosave; | |
135 | ||
5474c120 MH |
136 | /* Special case for the old PowerBook since I can't test on it */ |
137 | autosave = | |
138 | machine_is_compatible("AAPL,3400/2400") || | |
139 | machine_is_compatible("AAPL,3500"); | |
140 | ||
141 | if (!autosave && | |
142 | !pmac_has_backlight_type("pmu") && | |
143 | !machine_is_compatible("AAPL,PowerBook1998") && | |
144 | !machine_is_compatible("PowerBook1,1")) | |
145 | return; | |
146 | ||
d565dd3b | 147 | snprintf(name, sizeof(name), "pmubl"); |
5474c120 | 148 | |
96ceeaf4 | 149 | bd = backlight_device_register(name, NULL, NULL, &pmu_backlight_data); |
5474c120 MH |
150 | if (IS_ERR(bd)) { |
151 | printk("pmubl: Backlight registration failed\n"); | |
152 | goto error; | |
153 | } | |
599a52d1 | 154 | bd->props.max_brightness = FB_BACKLIGHT_LEVELS - 1; |
d565dd3b | 155 | pmu_backlight_init_curve(0x7F, 0x46, 0x0E); |
5474c120 | 156 | |
599a52d1 | 157 | level = bd->props.max_brightness; |
5474c120 MH |
158 | |
159 | if (autosave) { | |
160 | /* read autosaved value if available */ | |
161 | struct adb_request req; | |
162 | pmu_request(&req, NULL, 2, 0xd9, 0); | |
163 | pmu_wait_complete(&req); | |
164 | ||
d565dd3b | 165 | level = pmu_backlight_curve_lookup( |
5474c120 | 166 | (req.reply[0] >> 4) * |
599a52d1 | 167 | bd->props.max_brightness / 15); |
5474c120 MH |
168 | } |
169 | ||
599a52d1 RP |
170 | bd->props.brightness = level; |
171 | bd->props.power = FB_BLANK_UNBLANK; | |
28ee086d | 172 | backlight_update_status(bd); |
5474c120 | 173 | |
5474c120 MH |
174 | printk("pmubl: Backlight initialized (%s)\n", name); |
175 | ||
176 | return; | |
177 | ||
178 | error: | |
179 | return; | |
180 | } |