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-rw-r--r--drivers/macintosh/via-pmu-backlight.c150
1 files changed, 150 insertions, 0 deletions
diff --git a/drivers/macintosh/via-pmu-backlight.c b/drivers/macintosh/via-pmu-backlight.c
new file mode 100644
index 000000000000..b42d05f2aaff
--- /dev/null
+++ b/drivers/macintosh/via-pmu-backlight.c
@@ -0,0 +1,150 @@
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
18static struct device_node *vias;
19static struct backlight_properties pmu_backlight_data;
20
21static int pmu_backlight_get_level_brightness(struct fb_info *info,
22 int level)
23{
24 int pmulevel;
25
26 /* Get and convert the value */
27 mutex_lock(&info->bl_mutex);
28 pmulevel = info->bl_curve[level] * FB_BACKLIGHT_MAX / MAX_PMU_LEVEL;
29 mutex_unlock(&info->bl_mutex);
30
31 if (pmulevel < 0)
32 pmulevel = 0;
33 else if (pmulevel > MAX_PMU_LEVEL)
34 pmulevel = MAX_PMU_LEVEL;
35
36 return pmulevel;
37}
38
39static int pmu_backlight_update_status(struct backlight_device *bd)
40{
41 struct fb_info *info = class_get_devdata(&bd->class_dev);
42 struct adb_request req;
43 int pmulevel, level = bd->props->brightness;
44
45 if (vias == NULL)
46 return -ENODEV;
47
48 if (bd->props->power != FB_BLANK_UNBLANK ||
49 bd->props->fb_blank != FB_BLANK_UNBLANK)
50 level = 0;
51
52 pmulevel = pmu_backlight_get_level_brightness(info, level);
53
54 pmu_request(&req, NULL, 2, PMU_BACKLIGHT_BRIGHT, pmulevel);
55 pmu_wait_complete(&req);
56
57 pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
58 PMU_POW_BACKLIGHT | (level > 0 ? PMU_POW_ON : PMU_POW_OFF));
59 pmu_wait_complete(&req);
60
61 return 0;
62}
63
64static int pmu_backlight_get_brightness(struct backlight_device *bd)
65{
66 return bd->props->brightness;
67}
68
69static struct backlight_properties pmu_backlight_data = {
70 .owner = THIS_MODULE,
71 .get_brightness = pmu_backlight_get_brightness,
72 .update_status = pmu_backlight_update_status,
73 .max_brightness = (FB_BACKLIGHT_LEVELS - 1),
74};
75
76void __init pmu_backlight_init(struct device_node *in_vias)
77{
78 struct backlight_device *bd;
79 struct fb_info *info;
80 char name[10];
81 int level, autosave;
82
83 vias = in_vias;
84
85 /* Special case for the old PowerBook since I can't test on it */
86 autosave =
87 machine_is_compatible("AAPL,3400/2400") ||
88 machine_is_compatible("AAPL,3500");
89
90 if (!autosave &&
91 !pmac_has_backlight_type("pmu") &&
92 !machine_is_compatible("AAPL,PowerBook1998") &&
93 !machine_is_compatible("PowerBook1,1"))
94 return;
95
96 /* Actually, this is a hack, but I don't know of a better way
97 * to get the first framebuffer device.
98 */
99 info = registered_fb[0];
100 if (!info) {
101 printk("pmubl: No framebuffer found\n");
102 goto error;
103 }
104
105 snprintf(name, sizeof(name), "pmubl%d", info->node);
106
107 bd = backlight_device_register(name, info, &pmu_backlight_data);
108 if (IS_ERR(bd)) {
109 printk("pmubl: Backlight registration failed\n");
110 goto error;
111 }
112
113 mutex_lock(&info->bl_mutex);
114 info->bl_dev = bd;
115 fb_bl_default_curve(info, 0x7F, 0x46, 0x0E);
116 mutex_unlock(&info->bl_mutex);
117
118 level = pmu_backlight_data.max_brightness;
119
120 if (autosave) {
121 /* read autosaved value if available */
122 struct adb_request req;
123 pmu_request(&req, NULL, 2, 0xd9, 0);
124 pmu_wait_complete(&req);
125
126 mutex_lock(&info->bl_mutex);
127 level = pmac_backlight_curve_lookup(info,
128 (req.reply[0] >> 4) *
129 pmu_backlight_data.max_brightness / 15);
130 mutex_unlock(&info->bl_mutex);
131 }
132
133 up(&bd->sem);
134 bd->props->brightness = level;
135 bd->props->power = FB_BLANK_UNBLANK;
136 bd->props->update_status(bd);
137 down(&bd->sem);
138
139 mutex_lock(&pmac_backlight_mutex);
140 if (!pmac_backlight)
141 pmac_backlight = bd;
142 mutex_unlock(&pmac_backlight_mutex);
143
144 printk("pmubl: Backlight initialized (%s)\n", name);
145
146 return;
147
148error:
149 return;
150}