summaryrefslogtreecommitdiffstats
path: root/arch/ppc/platforms/pmac_backlight.c
blob: ed2b1cebc19ae3ec28dc5ce11b010c6d861add81 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
/*
 * Miscellaneous procedures for dealing with the PowerMac hardware.
 * Contains support for the backlight.
 *
 *   Copyright (C) 2000 Benjamin Herrenschmidt
 *
 */

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/stddef.h>
#include <linux/reboot.h>
#include <linux/nvram.h>
#include <linux/console.h>
#include <asm/sections.h>
#include <asm/ptrace.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/nvram.h>
#include <asm/backlight.h>

#include <linux/adb.h>
#include <linux/pmu.h>

static struct backlight_controller *backlighter;
static void* backlighter_data;
static int backlight_autosave;
static int backlight_level = BACKLIGHT_MAX;
static int backlight_enabled = 1;
static int backlight_req_level = -1;
static int backlight_req_enable = -1;

static void backlight_callback(void *);
static DECLARE_WORK(backlight_work, backlight_callback, NULL);

void __pmac register_backlight_controller(struct backlight_controller *ctrler,
					  void *data, char *type)
{
	struct device_node* bk_node;
	char *prop;
	int valid = 0;

	/* There's already a matching controller, bail out */
	if (backlighter != NULL)
		return;

	bk_node = find_devices("backlight");

#ifdef CONFIG_ADB_PMU
	/* Special case for the old PowerBook since I can't test on it */
	backlight_autosave = machine_is_compatible("AAPL,3400/2400")
		|| machine_is_compatible("AAPL,3500");
	if ((backlight_autosave
	     || machine_is_compatible("AAPL,PowerBook1998")
	     || machine_is_compatible("PowerBook1,1"))
	    && !strcmp(type, "pmu"))
		valid = 1;
#endif
	if (bk_node) {
		prop = get_property(bk_node, "backlight-control", NULL);
		if (prop && !strncmp(prop, type, strlen(type)))
			valid = 1;
	}
	if (!valid)
		return;
	backlighter = ctrler;
	backlighter_data = data;

	if (bk_node && !backlight_autosave)
		prop = get_property(bk_node, "bklt", NULL);
	else
		prop = NULL;
	if (prop) {
		backlight_level = ((*prop)+1) >> 1;
		if (backlight_level > BACKLIGHT_MAX)
			backlight_level = BACKLIGHT_MAX;
	}

#ifdef CONFIG_ADB_PMU
	if (backlight_autosave) {
		struct adb_request req;
		pmu_request(&req, NULL, 2, 0xd9, 0);
		while (!req.complete)
			pmu_poll();
		backlight_level = req.reply[0] >> 4;
	}
#endif
	acquire_console_sem();
	if (!backlighter->set_enable(1, backlight_level, data))
		backlight_enabled = 1;
	release_console_sem();

	printk(KERN_INFO "Registered \"%s\" backlight controller,"
	       "level: %d/15\n", type, backlight_level);
}
EXPORT_SYMBOL(register_backlight_controller);

void __pmac unregister_backlight_controller(struct backlight_controller
					    *ctrler, void *data)
{
	/* We keep the current backlight level (for now) */
	if (ctrler == backlighter && data == backlighter_data)
		backlighter = NULL;
}
EXPORT_SYMBOL(unregister_backlight_controller);

static int __pmac __set_backlight_enable(int enable)
{
	int rc;

	if (!backlighter)
		return -ENODEV;
	acquire_console_sem();
	rc = backlighter->set_enable(enable, backlight_level,
				     backlighter_data);
	if (!rc)
		backlight_enabled = enable;
	release_console_sem();
	return rc;
}
int __pmac set_backlight_enable(int enable)
{
	if (!backlighter)
		return -ENODEV;
	backlight_req_enable = enable;
	schedule_work(&backlight_work);
	return 0;
}

EXPORT_SYMBOL(set_backlight_enable);

int __pmac get_backlight_enable(void)
{
	if (!backlighter)
		return -ENODEV;
	return backlight_enabled;
}
EXPORT_SYMBOL(get_backlight_enable);

static int __pmac __set_backlight_level(int level)
{
	int rc = 0;

	if (!backlighter)
		return -ENODEV;
	if (level < BACKLIGHT_MIN)
		level = BACKLIGHT_OFF;
	if (level > BACKLIGHT_MAX)
		level = BACKLIGHT_MAX;
	acquire_console_sem();
	if (backlight_enabled)
		rc = backlighter->set_level(level, backlighter_data);
	if (!rc)
		backlight_level = level;
	release_console_sem();
	if (!rc && !backlight_autosave) {
		level <<=1;
		if (level & 0x10)
			level |= 0x01;
		// -- todo: save to property "bklt"
	}
	return rc;
}
int __pmac set_backlight_level(int level)
{
	if (!backlighter)
		return -ENODEV;
	backlight_req_level = level;
	schedule_work(&backlight_work);
	return 0;
}

EXPORT_SYMBOL(set_backlight_level);

int __pmac get_backlight_level(void)
{
	if (!backlighter)
		return -ENODEV;
	return backlight_level;
}
EXPORT_SYMBOL(get_backlight_level);

static void backlight_callback(void *dummy)
{
	int level, enable;

	do {
		level = backlight_req_level;
		enable = backlight_req_enable;
		mb();

		if (level >= 0)
			__set_backlight_level(level);
		if (enable >= 0)
			__set_backlight_enable(enable);
	} while(cmpxchg(&backlight_req_level, level, -1) != level ||
		cmpxchg(&backlight_req_enable, enable, -1) != enable);
}
OpenPOWER on IntegriCloud