memcg: fix possible panic when CONFIG_MM_OWNER=y
[linux-2.6/mini2440.git] / drivers / video / aty / radeon_backlight.c
blob1a056adb61c836784fce99d1c0314e710f4948e8
1 /*
2 * Backlight code for ATI Radeon based graphic cards
4 * Copyright (c) 2000 Ani Joshi <ajoshi@kernel.crashing.org>
5 * Copyright (c) 2003 Benjamin Herrenschmidt <benh@kernel.crashing.org>
6 * Copyright (c) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include "radeonfb.h"
14 #include <linux/backlight.h>
16 #ifdef CONFIG_PMAC_BACKLIGHT
17 #include <asm/backlight.h>
18 #endif
20 #define MAX_RADEON_LEVEL 0xFF
22 struct radeon_bl_privdata {
23 struct radeonfb_info *rinfo;
24 uint8_t negative;
27 static int radeon_bl_get_level_brightness(struct radeon_bl_privdata *pdata,
28 int level)
30 int rlevel;
32 /* Get and convert the value */
33 /* No locking of bl_curve since we read a single value */
34 rlevel = pdata->rinfo->info->bl_curve[level] *
35 FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL;
37 if (rlevel < 0)
38 rlevel = 0;
39 else if (rlevel > MAX_RADEON_LEVEL)
40 rlevel = MAX_RADEON_LEVEL;
42 if (pdata->negative)
43 rlevel = MAX_RADEON_LEVEL - rlevel;
45 return rlevel;
48 static int radeon_bl_update_status(struct backlight_device *bd)
50 struct radeon_bl_privdata *pdata = bl_get_data(bd);
51 struct radeonfb_info *rinfo = pdata->rinfo;
52 u32 lvds_gen_cntl, tmpPixclksCntl;
53 int level;
55 if (rinfo->mon1_type != MT_LCD)
56 return 0;
58 /* We turn off the LCD completely instead of just dimming the
59 * backlight. This provides some greater power saving and the display
60 * is useless without backlight anyway.
62 if (bd->props.power != FB_BLANK_UNBLANK ||
63 bd->props.fb_blank != FB_BLANK_UNBLANK)
64 level = 0;
65 else
66 level = bd->props.brightness;
68 del_timer_sync(&rinfo->lvds_timer);
69 radeon_engine_idle();
71 lvds_gen_cntl = INREG(LVDS_GEN_CNTL);
72 if (level > 0) {
73 lvds_gen_cntl &= ~LVDS_DISPLAY_DIS;
74 if (!(lvds_gen_cntl & LVDS_BLON) || !(lvds_gen_cntl & LVDS_ON)) {
75 lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_DIGON);
76 lvds_gen_cntl |= LVDS_BLON | LVDS_EN;
77 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
78 lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
79 lvds_gen_cntl |=
80 (radeon_bl_get_level_brightness(pdata, level) <<
81 LVDS_BL_MOD_LEVEL_SHIFT);
82 lvds_gen_cntl |= LVDS_ON;
83 lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_BL_MOD_EN);
84 rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
85 mod_timer(&rinfo->lvds_timer,
86 jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
87 } else {
88 lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
89 lvds_gen_cntl |=
90 (radeon_bl_get_level_brightness(pdata, level) <<
91 LVDS_BL_MOD_LEVEL_SHIFT);
92 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
94 rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
95 rinfo->init_state.lvds_gen_cntl |= rinfo->pending_lvds_gen_cntl
96 & LVDS_STATE_MASK;
97 } else {
98 /* Asic bug, when turning off LVDS_ON, we have to make sure
99 RADEON_PIXCLK_LVDS_ALWAYS_ON bit is off
101 tmpPixclksCntl = INPLL(PIXCLKS_CNTL);
102 if (rinfo->is_mobility || rinfo->is_IGP)
103 OUTPLLP(PIXCLKS_CNTL, 0, ~PIXCLK_LVDS_ALWAYS_ONb);
104 lvds_gen_cntl &= ~(LVDS_BL_MOD_LEVEL_MASK | LVDS_BL_MOD_EN);
105 lvds_gen_cntl |= (radeon_bl_get_level_brightness(pdata, 0) <<
106 LVDS_BL_MOD_LEVEL_SHIFT);
107 lvds_gen_cntl |= LVDS_DISPLAY_DIS;
108 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
109 udelay(100);
110 lvds_gen_cntl &= ~(LVDS_ON | LVDS_EN);
111 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
112 lvds_gen_cntl &= ~(LVDS_DIGON);
113 rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
114 mod_timer(&rinfo->lvds_timer,
115 jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
116 if (rinfo->is_mobility || rinfo->is_IGP)
117 OUTPLL(PIXCLKS_CNTL, tmpPixclksCntl);
119 rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
120 rinfo->init_state.lvds_gen_cntl |= (lvds_gen_cntl & LVDS_STATE_MASK);
122 return 0;
125 static int radeon_bl_get_brightness(struct backlight_device *bd)
127 return bd->props.brightness;
130 static struct backlight_ops radeon_bl_data = {
131 .get_brightness = radeon_bl_get_brightness,
132 .update_status = radeon_bl_update_status,
135 void radeonfb_bl_init(struct radeonfb_info *rinfo)
137 struct backlight_device *bd;
138 struct radeon_bl_privdata *pdata;
139 char name[12];
141 if (rinfo->mon1_type != MT_LCD)
142 return;
144 #ifdef CONFIG_PMAC_BACKLIGHT
145 if (!pmac_has_backlight_type("ati") &&
146 !pmac_has_backlight_type("mnca"))
147 return;
148 #endif
150 pdata = kmalloc(sizeof(struct radeon_bl_privdata), GFP_KERNEL);
151 if (!pdata) {
152 printk("radeonfb: Memory allocation failed\n");
153 goto error;
156 snprintf(name, sizeof(name), "radeonbl%d", rinfo->info->node);
158 bd = backlight_device_register(name, rinfo->info->dev, pdata, &radeon_bl_data);
159 if (IS_ERR(bd)) {
160 rinfo->info->bl_dev = NULL;
161 printk("radeonfb: Backlight registration failed\n");
162 goto error;
165 pdata->rinfo = rinfo;
167 /* Pardon me for that hack... maybe some day we can figure out in what
168 * direction backlight should work on a given panel?
170 pdata->negative =
171 (rinfo->family != CHIP_FAMILY_RV200 &&
172 rinfo->family != CHIP_FAMILY_RV250 &&
173 rinfo->family != CHIP_FAMILY_RV280 &&
174 rinfo->family != CHIP_FAMILY_RV350);
176 #ifdef CONFIG_PMAC_BACKLIGHT
177 pdata->negative = pdata->negative ||
178 machine_is_compatible("PowerBook4,3") ||
179 machine_is_compatible("PowerBook6,3") ||
180 machine_is_compatible("PowerBook6,5");
181 #endif
183 rinfo->info->bl_dev = bd;
184 fb_bl_default_curve(rinfo->info, 0,
185 63 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL,
186 217 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL);
188 bd->props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
189 bd->props.brightness = bd->props.max_brightness;
190 bd->props.power = FB_BLANK_UNBLANK;
191 backlight_update_status(bd);
193 printk("radeonfb: Backlight initialized (%s)\n", name);
195 return;
197 error:
198 kfree(pdata);
199 return;
202 void radeonfb_bl_exit(struct radeonfb_info *rinfo)
204 struct backlight_device *bd = rinfo->info->bl_dev;
206 if (bd) {
207 struct radeon_bl_privdata *pdata;
209 pdata = bl_get_data(bd);
210 backlight_device_unregister(bd);
211 kfree(pdata);
212 rinfo->info->bl_dev = NULL;
214 printk("radeonfb: Backlight unloaded\n");