1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Backlight Driver for the KB3886 Backlight |
4 | * |
5 | * Copyright (c) 2007-2008 Claudio Nieder |
6 | * |
7 | * Based on corgi_bl.c by Richard Purdie and kb3886 driver by Robert Woerle |
8 | */ |
9 | |
10 | #include <linux/module.h> |
11 | #include <linux/kernel.h> |
12 | #include <linux/init.h> |
13 | #include <linux/platform_device.h> |
14 | #include <linux/mutex.h> |
15 | #include <linux/fb.h> |
16 | #include <linux/backlight.h> |
17 | #include <linux/delay.h> |
18 | #include <linux/dmi.h> |
19 | |
20 | #define KB3886_PARENT 0x64 |
21 | #define KB3886_IO 0x60 |
22 | #define KB3886_ADC_DAC_PWM 0xC4 |
23 | #define KB3886_PWM0_WRITE 0x81 |
24 | #define KB3886_PWM0_READ 0x41 |
25 | |
26 | static DEFINE_MUTEX(bl_mutex); |
27 | |
28 | static void kb3886_bl_set_intensity(int intensity) |
29 | { |
30 | mutex_lock(&bl_mutex); |
31 | intensity = intensity&0xff; |
32 | outb(KB3886_ADC_DAC_PWM, KB3886_PARENT); |
33 | usleep_range(min: 10000, max: 11000); |
34 | outb(KB3886_PWM0_WRITE, KB3886_IO); |
35 | usleep_range(min: 10000, max: 11000); |
36 | outb(value: intensity, KB3886_IO); |
37 | mutex_unlock(lock: &bl_mutex); |
38 | } |
39 | |
40 | struct kb3886bl_machinfo { |
41 | int max_intensity; |
42 | int default_intensity; |
43 | int limit_mask; |
44 | void (*set_bl_intensity)(int intensity); |
45 | }; |
46 | |
47 | static struct kb3886bl_machinfo kb3886_bl_machinfo = { |
48 | .max_intensity = 0xff, |
49 | .default_intensity = 0xa0, |
50 | .limit_mask = 0x7f, |
51 | .set_bl_intensity = kb3886_bl_set_intensity, |
52 | }; |
53 | |
54 | static struct platform_device kb3886bl_device = { |
55 | .name = "kb3886-bl" , |
56 | .dev = { |
57 | .platform_data = &kb3886_bl_machinfo, |
58 | }, |
59 | .id = -1, |
60 | }; |
61 | |
62 | static struct platform_device *devices[] __initdata = { |
63 | &kb3886bl_device, |
64 | }; |
65 | |
66 | /* |
67 | * Back to driver |
68 | */ |
69 | |
70 | static int kb3886bl_intensity; |
71 | static struct backlight_device *kb3886_backlight_device; |
72 | static struct kb3886bl_machinfo *bl_machinfo; |
73 | |
74 | static unsigned long kb3886bl_flags; |
75 | #define KB3886BL_SUSPENDED 0x01 |
76 | |
77 | static const struct dmi_system_id kb3886bl_device_table[] __initconst = { |
78 | { |
79 | .ident = "Sahara Touch-iT" , |
80 | .matches = { |
81 | DMI_MATCH(DMI_SYS_VENDOR, "SDV" ), |
82 | DMI_MATCH(DMI_PRODUCT_NAME, "iTouch T201" ), |
83 | }, |
84 | }, |
85 | { } |
86 | }; |
87 | |
88 | static int kb3886bl_send_intensity(struct backlight_device *bd) |
89 | { |
90 | int intensity = backlight_get_brightness(bd); |
91 | |
92 | if (kb3886bl_flags & KB3886BL_SUSPENDED) |
93 | intensity = 0; |
94 | |
95 | bl_machinfo->set_bl_intensity(intensity); |
96 | |
97 | kb3886bl_intensity = intensity; |
98 | return 0; |
99 | } |
100 | |
101 | #ifdef CONFIG_PM_SLEEP |
102 | static int kb3886bl_suspend(struct device *dev) |
103 | { |
104 | struct backlight_device *bd = dev_get_drvdata(dev); |
105 | |
106 | kb3886bl_flags |= KB3886BL_SUSPENDED; |
107 | backlight_update_status(bd); |
108 | return 0; |
109 | } |
110 | |
111 | static int kb3886bl_resume(struct device *dev) |
112 | { |
113 | struct backlight_device *bd = dev_get_drvdata(dev); |
114 | |
115 | kb3886bl_flags &= ~KB3886BL_SUSPENDED; |
116 | backlight_update_status(bd); |
117 | return 0; |
118 | } |
119 | #endif |
120 | |
121 | static SIMPLE_DEV_PM_OPS(kb3886bl_pm_ops, kb3886bl_suspend, kb3886bl_resume); |
122 | |
123 | static int kb3886bl_get_intensity(struct backlight_device *bd) |
124 | { |
125 | return kb3886bl_intensity; |
126 | } |
127 | |
128 | static const struct backlight_ops kb3886bl_ops = { |
129 | .get_brightness = kb3886bl_get_intensity, |
130 | .update_status = kb3886bl_send_intensity, |
131 | }; |
132 | |
133 | static int kb3886bl_probe(struct platform_device *pdev) |
134 | { |
135 | struct backlight_properties props; |
136 | struct kb3886bl_machinfo *machinfo = dev_get_platdata(dev: &pdev->dev); |
137 | |
138 | bl_machinfo = machinfo; |
139 | if (!machinfo->limit_mask) |
140 | machinfo->limit_mask = -1; |
141 | |
142 | memset(&props, 0, sizeof(struct backlight_properties)); |
143 | props.type = BACKLIGHT_RAW; |
144 | props.max_brightness = machinfo->max_intensity; |
145 | kb3886_backlight_device = devm_backlight_device_register(dev: &pdev->dev, |
146 | name: "kb3886-bl" , parent: &pdev->dev, |
147 | NULL, ops: &kb3886bl_ops, |
148 | props: &props); |
149 | if (IS_ERR(ptr: kb3886_backlight_device)) |
150 | return PTR_ERR(ptr: kb3886_backlight_device); |
151 | |
152 | platform_set_drvdata(pdev, data: kb3886_backlight_device); |
153 | |
154 | kb3886_backlight_device->props.power = FB_BLANK_UNBLANK; |
155 | kb3886_backlight_device->props.brightness = machinfo->default_intensity; |
156 | backlight_update_status(bd: kb3886_backlight_device); |
157 | |
158 | return 0; |
159 | } |
160 | |
161 | static struct platform_driver kb3886bl_driver = { |
162 | .probe = kb3886bl_probe, |
163 | .driver = { |
164 | .name = "kb3886-bl" , |
165 | .pm = &kb3886bl_pm_ops, |
166 | }, |
167 | }; |
168 | |
169 | static int __init kb3886_init(void) |
170 | { |
171 | if (!dmi_check_system(list: kb3886bl_device_table)) |
172 | return -ENODEV; |
173 | |
174 | platform_add_devices(devices, ARRAY_SIZE(devices)); |
175 | return platform_driver_register(&kb3886bl_driver); |
176 | } |
177 | |
178 | static void __exit kb3886_exit(void) |
179 | { |
180 | platform_driver_unregister(&kb3886bl_driver); |
181 | } |
182 | |
183 | module_init(kb3886_init); |
184 | module_exit(kb3886_exit); |
185 | |
186 | MODULE_AUTHOR("Claudio Nieder <private@claudio.ch>" ); |
187 | MODULE_DESCRIPTION("Tabletkiosk Sahara Touch-iT Backlight Driver" ); |
188 | MODULE_LICENSE("GPL" ); |
189 | MODULE_ALIAS("dmi:*:svnSDV:pniTouchT201:*" ); |
190 | |