tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Generic Backlight Driver
4 *
5 * Copyright (c) 2004-2008 Richard Purdie
6 */
7
8#include <linux/module.h>
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/platform_device.h>
12#include <linux/mutex.h>
13#include <linux/fb.h>
14#include <linux/backlight.h>
15
16static int genericbl_intensity;
17static struct backlight_device *generic_backlight_device;
18static struct generic_bl_info *bl_machinfo;
19
20static int genericbl_send_intensity(struct backlight_device *bd)
21{
22 int intensity = bd->props.brightness;
23
24 if (bd->props.power != FB_BLANK_UNBLANK)
25 intensity = 0;
26 if (bd->props.state & BL_CORE_FBBLANK)
27 intensity = 0;
28 if (bd->props.state & BL_CORE_SUSPENDED)
29 intensity = 0;
30
31 bl_machinfo->set_bl_intensity(intensity);
32
33 genericbl_intensity = intensity;
34
35 if (bl_machinfo->kick_battery)
36 bl_machinfo->kick_battery();
37
38 return 0;
39}
40
41static int genericbl_get_intensity(struct backlight_device *bd)
42{
43 return genericbl_intensity;
44}
45
46static const struct backlight_ops genericbl_ops = {
47 .options = BL_CORE_SUSPENDRESUME,
48 .get_brightness = genericbl_get_intensity,
49 .update_status = genericbl_send_intensity,
50};
51
52static int genericbl_probe(struct platform_device *pdev)
53{
54 struct backlight_properties props;
55 struct generic_bl_info *machinfo = dev_get_platdata(&pdev->dev);
56 const char *name = "generic-bl";
57 struct backlight_device *bd;
58
59 bl_machinfo = machinfo;
60 if (!machinfo->limit_mask)
61 machinfo->limit_mask = -1;
62
63 if (machinfo->name)
64 name = machinfo->name;
65
66 memset(&props, 0, sizeof(struct backlight_properties));
67 props.type = BACKLIGHT_RAW;
68 props.max_brightness = machinfo->max_intensity;
69 bd = devm_backlight_device_register(&pdev->dev, name, &pdev->dev,
70 NULL, &genericbl_ops, &props);
71 if (IS_ERR(bd))
72 return PTR_ERR(bd);
73
74 platform_set_drvdata(pdev, bd);
75
76 bd->props.power = FB_BLANK_UNBLANK;
77 bd->props.brightness = machinfo->default_intensity;
78 backlight_update_status(bd);
79
80 generic_backlight_device = bd;
81
82 dev_info(&pdev->dev, "Generic Backlight Driver Initialized.\n");
83 return 0;
84}
85
86static int genericbl_remove(struct platform_device *pdev)
87{
88 struct backlight_device *bd = platform_get_drvdata(pdev);
89
90 bd->props.power = 0;
91 bd->props.brightness = 0;
92 backlight_update_status(bd);
93
94 dev_info(&pdev->dev, "Generic Backlight Driver Unloaded\n");
95 return 0;
96}
97
98static struct platform_driver genericbl_driver = {
99 .probe = genericbl_probe,
100 .remove = genericbl_remove,
101 .driver = {
102 .name = "generic-bl",
103 },
104};
105
106module_platform_driver(genericbl_driver);
107
108MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
109MODULE_DESCRIPTION("Generic Backlight Driver");
110MODULE_LICENSE("GPL");