1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Backlight code for ATI Radeon based graphic cards
4 *
5 * Copyright (c) 2000 Ani Joshi <ajoshi@kernel.crashing.org>
6 * Copyright (c) 2003 Benjamin Herrenschmidt <benh@kernel.crashing.org>
7 * Copyright (c) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
8 */
9
10 #include "radeonfb.h"
11 #include <linux/backlight.h>
12 #include <linux/slab.h>
13
14 #ifdef CONFIG_PMAC_BACKLIGHT
15 #include <asm/backlight.h>
16 #endif
17
18 #define MAX_RADEON_LEVEL 0xFF
19
20 struct radeon_bl_privdata {
21 struct radeonfb_info *rinfo;
22 uint8_t negative;
23 };
24
radeon_bl_get_level_brightness(struct radeon_bl_privdata * pdata,int level)25 static int radeon_bl_get_level_brightness(struct radeon_bl_privdata *pdata,
26 int level)
27 {
28 int rlevel;
29
30 /* Get and convert the value */
31 /* No locking of bl_curve since we read a single value */
32 rlevel = pdata->rinfo->info->bl_curve[level] *
33 FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL;
34
35 if (rlevel < 0)
36 rlevel = 0;
37 else if (rlevel > MAX_RADEON_LEVEL)
38 rlevel = MAX_RADEON_LEVEL;
39
40 if (pdata->negative)
41 rlevel = MAX_RADEON_LEVEL - rlevel;
42
43 return rlevel;
44 }
45
radeon_bl_update_status(struct backlight_device * bd)46 static int radeon_bl_update_status(struct backlight_device *bd)
47 {
48 struct radeon_bl_privdata *pdata = bl_get_data(bd);
49 struct radeonfb_info *rinfo = pdata->rinfo;
50 u32 lvds_gen_cntl, tmpPixclksCntl;
51 int level;
52
53 if (rinfo->mon1_type != MT_LCD)
54 return 0;
55
56 /* We turn off the LCD completely instead of just dimming the
57 * backlight. This provides some greater power saving and the display
58 * is useless without backlight anyway.
59 */
60 if (bd->props.power != FB_BLANK_UNBLANK ||
61 bd->props.fb_blank != FB_BLANK_UNBLANK)
62 level = 0;
63 else
64 level = bd->props.brightness;
65
66 del_timer_sync(&rinfo->lvds_timer);
67 radeon_engine_idle();
68
69 lvds_gen_cntl = INREG(LVDS_GEN_CNTL);
70 if (level > 0) {
71 lvds_gen_cntl &= ~LVDS_DISPLAY_DIS;
72 if (!(lvds_gen_cntl & LVDS_BLON) || !(lvds_gen_cntl & LVDS_ON)) {
73 lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_DIGON);
74 lvds_gen_cntl |= LVDS_BLON | LVDS_EN;
75 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
76 lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
77 lvds_gen_cntl |=
78 (radeon_bl_get_level_brightness(pdata, level) <<
79 LVDS_BL_MOD_LEVEL_SHIFT);
80 lvds_gen_cntl |= LVDS_ON;
81 lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_BL_MOD_EN);
82 rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
83 mod_timer(&rinfo->lvds_timer,
84 jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
85 } else {
86 lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
87 lvds_gen_cntl |=
88 (radeon_bl_get_level_brightness(pdata, level) <<
89 LVDS_BL_MOD_LEVEL_SHIFT);
90 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
91 }
92 rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
93 rinfo->init_state.lvds_gen_cntl |= rinfo->pending_lvds_gen_cntl
94 & LVDS_STATE_MASK;
95 } else {
96 /* Asic bug, when turning off LVDS_ON, we have to make sure
97 RADEON_PIXCLK_LVDS_ALWAYS_ON bit is off
98 */
99 tmpPixclksCntl = INPLL(PIXCLKS_CNTL);
100 if (rinfo->is_mobility || rinfo->is_IGP)
101 OUTPLLP(PIXCLKS_CNTL, 0, ~PIXCLK_LVDS_ALWAYS_ONb);
102 lvds_gen_cntl &= ~(LVDS_BL_MOD_LEVEL_MASK | LVDS_BL_MOD_EN);
103 lvds_gen_cntl |= (radeon_bl_get_level_brightness(pdata, 0) <<
104 LVDS_BL_MOD_LEVEL_SHIFT);
105 lvds_gen_cntl |= LVDS_DISPLAY_DIS;
106 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
107 udelay(100);
108 lvds_gen_cntl &= ~(LVDS_ON | LVDS_EN);
109 OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
110 lvds_gen_cntl &= ~(LVDS_DIGON);
111 rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
112 mod_timer(&rinfo->lvds_timer,
113 jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
114 if (rinfo->is_mobility || rinfo->is_IGP)
115 OUTPLL(PIXCLKS_CNTL, tmpPixclksCntl);
116 }
117 rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
118 rinfo->init_state.lvds_gen_cntl |= (lvds_gen_cntl & LVDS_STATE_MASK);
119
120 return 0;
121 }
122
123 static const struct backlight_ops radeon_bl_data = {
124 .update_status = radeon_bl_update_status,
125 };
126
radeonfb_bl_init(struct radeonfb_info * rinfo)127 void radeonfb_bl_init(struct radeonfb_info *rinfo)
128 {
129 struct backlight_properties props;
130 struct backlight_device *bd;
131 struct radeon_bl_privdata *pdata;
132 char name[12];
133
134 if (rinfo->mon1_type != MT_LCD)
135 return;
136
137 #ifdef CONFIG_PMAC_BACKLIGHT
138 if (!pmac_has_backlight_type("ati") &&
139 !pmac_has_backlight_type("mnca"))
140 return;
141 #endif
142
143 pdata = kmalloc(sizeof(struct radeon_bl_privdata), GFP_KERNEL);
144 if (!pdata) {
145 printk("radeonfb: Memory allocation failed\n");
146 goto error;
147 }
148
149 snprintf(name, sizeof(name), "radeonbl%d", rinfo->info->node);
150
151 memset(&props, 0, sizeof(struct backlight_properties));
152 props.type = BACKLIGHT_RAW;
153 props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
154 bd = backlight_device_register(name, rinfo->info->dev, pdata,
155 &radeon_bl_data, &props);
156 if (IS_ERR(bd)) {
157 rinfo->info->bl_dev = NULL;
158 printk("radeonfb: Backlight registration failed\n");
159 goto error;
160 }
161
162 pdata->rinfo = rinfo;
163
164 /* Pardon me for that hack... maybe some day we can figure out in what
165 * direction backlight should work on a given panel?
166 */
167 pdata->negative =
168 (rinfo->family != CHIP_FAMILY_RV200 &&
169 rinfo->family != CHIP_FAMILY_RV250 &&
170 rinfo->family != CHIP_FAMILY_RV280 &&
171 rinfo->family != CHIP_FAMILY_RV350);
172
173 #ifdef CONFIG_PMAC_BACKLIGHT
174 pdata->negative = pdata->negative ||
175 of_machine_is_compatible("PowerBook4,3") ||
176 of_machine_is_compatible("PowerBook6,3") ||
177 of_machine_is_compatible("PowerBook6,5");
178 #endif
179
180 rinfo->info->bl_dev = bd;
181 fb_bl_default_curve(rinfo->info, 0,
182 63 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL,
183 217 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL);
184
185 bd->props.brightness = bd->props.max_brightness;
186 bd->props.power = FB_BLANK_UNBLANK;
187 backlight_update_status(bd);
188
189 printk("radeonfb: Backlight initialized (%s)\n", name);
190
191 return;
192
193 error:
194 kfree(pdata);
195 return;
196 }
197
radeonfb_bl_exit(struct radeonfb_info * rinfo)198 void radeonfb_bl_exit(struct radeonfb_info *rinfo)
199 {
200 struct backlight_device *bd = rinfo->info->bl_dev;
201
202 if (bd) {
203 struct radeon_bl_privdata *pdata;
204
205 pdata = bl_get_data(bd);
206 backlight_device_unregister(bd);
207 kfree(pdata);
208 rinfo->info->bl_dev = NULL;
209
210 printk("radeonfb: Backlight unloaded\n");
211 }
212 }
213
