jcs.org
Control intel backlight on FreeBSD (and OpenBSD)
openbsd
1/*
2 * Copyright © 2011 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 * Chris Wilson <chris@chris-wilson.co.uk>
25 * Maurizio Vairani <maurizio.vairani@cloverinformatica.it>
26 */
27
28#include <stdint.h>
29#include <stdlib.h>
30#include <stdio.h>
31#include <string.h>
32
33#include "intel_gpu_tools.h"
34#define NUM_ELEMENTS(array) (sizeof(array) / sizeof(array[0]))
35
36/* XXX PCH only today */
37
38static uint32_t reg_read(uint32_t reg)
39{
40 return *(volatile uint32_t *)((volatile char*)mmio + reg);
41}
42
43static void reg_write(uint32_t reg, uint32_t val)
44{
45 *(volatile uint32_t *)((volatile char*)mmio + reg) = val;
46}
47
48static int brightness_levels[] = {1, 2, 4, 6, 9, 12, 16, 20, 25, 30, 36, 43,
49 51, 60, 70, 80, 90, 100};
50
51static int brightness_incr(int curr)
52{
53 int i;
54 for (i = 0; i < NUM_ELEMENTS(brightness_levels) - 1; ++i)
55 if (curr < brightness_levels[i])
56 break;
57 return brightness_levels[i];
58}
59
60static int brightness_decr(int curr)
61{
62 int i;
63 for (i = NUM_ELEMENTS(brightness_levels) - 1; i > 0; --i)
64 if (brightness_levels[i] < curr)
65 break;
66 return brightness_levels[i];
67}
68
69int main(int argc, char** argv)
70{
71 uint32_t current, max, min;
72 struct pci_device *dev;
73 int result;
74
75 dev = intel_get_pci_device();
76 intel_get_mmio(dev);
77
78 if (IS_GEN8(dev->device_id) || IS_GEN9(dev->device_id)) /* bdw/skl */
79 current = reg_read(BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
80 else
81 current = reg_read(BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
82
83 max = reg_read(BLC_PWM_PCH_CTL2) >> 16;
84
85 min = 0.5 + 0.5 * max / 100.0; // 0.5%
86 result = 0.5 + current * 100.0 / max;
87
88 printf ("%d", result);
89
90 if (argc > 1) {
91 uint32_t v;
92 if (0 == strcmp(argv[1], "incr"))
93 v = 0.5 + brightness_incr(result) * max / 100.0;
94 else if (0 == strcmp(argv[1], "decr"))
95 v = 0.5 + brightness_decr(result) * max / 100.0;
96 else
97 v = 0.5 + atoi (argv[1]) * max / 100.0;
98
99 if (v < min)
100 v = min;
101 else if (v > max)
102 v = max;
103
104 if (IS_GEN8(dev->device_id) || IS_GEN9(dev->device_id)) {
105 reg_write(BLC_PWM_PCH_CTL2,
106 (reg_read(BLC_PWM_PCH_CTL2) &~
107 BACKLIGHT_DUTY_CYCLE_MASK) | v);
108 (void) reg_read(BLC_PWM_PCH_CTL2);
109 } else {
110 reg_write(BLC_PWM_CPU_CTL,
111 (reg_read(BLC_PWM_CPU_CTL) &~
112 BACKLIGHT_DUTY_CYCLE_MASK) | v);
113 (void) reg_read(BLC_PWM_CPU_CTL);
114 }
115 result = 0.5 + v * 100.0 / max;
116 printf (" -> %d", result);
117 }
118
119 printf("\n");
120
121 return (0);
122}