CIFS: Fix endian conversion of vcnum field
[linux-2.6/mini2440.git] / drivers / macintosh / via-pmu-backlight.c
bloba348bb0791d37b764a2e61ffe55bacd57a12e182
1 /*
2 * Backlight code for via-pmu
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>
8 */
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>
16 #define MAX_PMU_LEVEL 0xFF
18 static struct backlight_ops pmu_backlight_data;
19 static DEFINE_SPINLOCK(pmu_backlight_lock);
20 static int sleeping, uses_pmu_bl;
21 static u8 bl_curve[FB_BACKLIGHT_LEVELS];
23 static void pmu_backlight_init_curve(u8 off, u8 min, u8 max)
25 int i, flat, count, range = (max - min);
27 bl_curve[0] = off;
29 for (flat = 1; flat < (FB_BACKLIGHT_LEVELS / 16); ++flat)
30 bl_curve[flat] = min;
32 count = FB_BACKLIGHT_LEVELS * 15 / 16;
33 for (i = 0; i < count; ++i)
34 bl_curve[flat + i] = min + (range * (i + 1) / count);
37 static int pmu_backlight_curve_lookup(int value)
39 int level = (FB_BACKLIGHT_LEVELS - 1);
40 int i, max = 0;
42 /* Look for biggest value */
43 for (i = 0; i < FB_BACKLIGHT_LEVELS; i++)
44 max = max((int)bl_curve[i], max);
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;
54 return level;
57 static int pmu_backlight_get_level_brightness(int level)
59 int pmulevel;
61 /* Get and convert the value */
62 pmulevel = bl_curve[level] * FB_BACKLIGHT_MAX / MAX_PMU_LEVEL;
63 if (pmulevel < 0)
64 pmulevel = 0;
65 else if (pmulevel > MAX_PMU_LEVEL)
66 pmulevel = MAX_PMU_LEVEL;
68 return pmulevel;
71 static int __pmu_backlight_update_status(struct backlight_device *bd)
73 struct adb_request req;
74 int level = bd->props.brightness;
77 if (bd->props.power != FB_BLANK_UNBLANK ||
78 bd->props.fb_blank != FB_BLANK_UNBLANK)
79 level = 0;
81 if (level > 0) {
82 int pmulevel = pmu_backlight_get_level_brightness(level);
84 pmu_request(&req, NULL, 2, PMU_BACKLIGHT_BRIGHT, pmulevel);
85 pmu_wait_complete(&req);
87 pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
88 PMU_POW_BACKLIGHT | PMU_POW_ON);
89 pmu_wait_complete(&req);
90 } else {
91 pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
92 PMU_POW_BACKLIGHT | PMU_POW_OFF);
93 pmu_wait_complete(&req);
96 return 0;
99 static int pmu_backlight_update_status(struct backlight_device *bd)
101 unsigned long flags;
102 int rc = 0;
104 spin_lock_irqsave(&pmu_backlight_lock, flags);
105 /* Don't update brightness when sleeping */
106 if (!sleeping)
107 rc = __pmu_backlight_update_status(bd);
108 spin_unlock_irqrestore(&pmu_backlight_lock, flags);
109 return rc;
113 static int pmu_backlight_get_brightness(struct backlight_device *bd)
115 return bd->props.brightness;
118 static struct backlight_ops pmu_backlight_data = {
119 .get_brightness = pmu_backlight_get_brightness,
120 .update_status = pmu_backlight_update_status,
124 #ifdef CONFIG_PM
125 void pmu_backlight_set_sleep(int sleep)
127 unsigned long flags;
129 spin_lock_irqsave(&pmu_backlight_lock, flags);
130 sleeping = sleep;
131 if (pmac_backlight && uses_pmu_bl) {
132 if (sleep) {
133 struct adb_request req;
135 pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
136 PMU_POW_BACKLIGHT | PMU_POW_OFF);
137 pmu_wait_complete(&req);
138 } else
139 __pmu_backlight_update_status(pmac_backlight);
141 spin_unlock_irqrestore(&pmu_backlight_lock, flags);
143 #endif /* CONFIG_PM */
145 void __init pmu_backlight_init()
147 struct backlight_device *bd;
148 char name[10];
149 int level, autosave;
151 /* Special case for the old PowerBook since I can't test on it */
152 autosave =
153 machine_is_compatible("AAPL,3400/2400") ||
154 machine_is_compatible("AAPL,3500");
156 if (!autosave &&
157 !pmac_has_backlight_type("pmu") &&
158 !machine_is_compatible("AAPL,PowerBook1998") &&
159 !machine_is_compatible("PowerBook1,1"))
160 return;
162 snprintf(name, sizeof(name), "pmubl");
164 bd = backlight_device_register(name, NULL, NULL, &pmu_backlight_data);
165 if (IS_ERR(bd)) {
166 printk(KERN_ERR "PMU Backlight registration failed\n");
167 return;
169 uses_pmu_bl = 1;
170 bd->props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
171 pmu_backlight_init_curve(0x7F, 0x46, 0x0E);
173 level = bd->props.max_brightness;
175 if (autosave) {
176 /* read autosaved value if available */
177 struct adb_request req;
178 pmu_request(&req, NULL, 2, 0xd9, 0);
179 pmu_wait_complete(&req);
181 level = pmu_backlight_curve_lookup(
182 (req.reply[0] >> 4) *
183 bd->props.max_brightness / 15);
186 bd->props.brightness = level;
187 bd->props.power = FB_BLANK_UNBLANK;
188 backlight_update_status(bd);
190 printk(KERN_INFO "PMU Backlight initialized (%s)\n", name);