Blame view

drivers/hid/hid-picolcd_backlight.c 4.08 KB
81f7e3824   Eric Lee   Initial Release, ...
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
  /***************************************************************************
   *   Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org>  *
   *                                                                         *
   *   Based on Logitech G13 driver (v0.4)                                   *
   *     Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu>   *
   *                                                                         *
   *   This program is free software: you can redistribute it and/or modify  *
   *   it under the terms of the GNU General Public License as published by  *
   *   the Free Software Foundation, version 2 of the License.               *
   *                                                                         *
   *   This driver is distributed in the hope that it will be useful, but    *
   *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
   *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
   *   General Public License for more details.                              *
   *                                                                         *
   *   You should have received a copy of the GNU General Public License     *
   *   along with this software. If not see <http://www.gnu.org/licenses/>.  *
   ***************************************************************************/
  
  #include <linux/hid.h>
  
  #include <linux/fb.h>
  #include <linux/backlight.h>
  
  #include "hid-picolcd.h"
  
  static int picolcd_get_brightness(struct backlight_device *bdev)
  {
  	struct picolcd_data *data = bl_get_data(bdev);
  	return data->lcd_brightness;
  }
  
  static int picolcd_set_brightness(struct backlight_device *bdev)
  {
  	struct picolcd_data *data = bl_get_data(bdev);
  	struct hid_report *report = picolcd_out_report(REPORT_BRIGHTNESS, data->hdev);
  	unsigned long flags;
  
  	if (!report || report->maxfield != 1 || report->field[0]->report_count != 1)
  		return -ENODEV;
  
  	data->lcd_brightness = bdev->props.brightness & 0x0ff;
  	data->lcd_power      = bdev->props.power;
  	spin_lock_irqsave(&data->lock, flags);
  	hid_set_field(report->field[0], 0, data->lcd_power == FB_BLANK_UNBLANK ? data->lcd_brightness : 0);
  	if (!(data->status & PICOLCD_FAILED))
  		hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT);
  	spin_unlock_irqrestore(&data->lock, flags);
  	return 0;
  }
  
  static int picolcd_check_bl_fb(struct backlight_device *bdev, struct fb_info *fb)
  {
  	return fb && fb == picolcd_fbinfo((struct picolcd_data *)bl_get_data(bdev));
  }
  
  static const struct backlight_ops picolcd_blops = {
  	.update_status  = picolcd_set_brightness,
  	.get_brightness = picolcd_get_brightness,
  	.check_fb       = picolcd_check_bl_fb,
  };
  
  int picolcd_init_backlight(struct picolcd_data *data, struct hid_report *report)
  {
  	struct device *dev = &data->hdev->dev;
  	struct backlight_device *bdev;
  	struct backlight_properties props;
  	if (!report)
  		return -ENODEV;
  	if (report->maxfield != 1 || report->field[0]->report_count != 1 ||
  			report->field[0]->report_size != 8) {
  		dev_err(dev, "unsupported BRIGHTNESS report");
  		return -EINVAL;
  	}
  
  	memset(&props, 0, sizeof(props));
  	props.type = BACKLIGHT_RAW;
  	props.max_brightness = 0xff;
  	bdev = backlight_device_register(dev_name(dev), dev, data,
  			&picolcd_blops, &props);
  	if (IS_ERR(bdev)) {
  		dev_err(dev, "failed to register backlight
  ");
  		return PTR_ERR(bdev);
  	}
  	bdev->props.brightness     = 0xff;
  	data->lcd_brightness       = 0xff;
  	data->backlight            = bdev;
  	picolcd_set_brightness(bdev);
  	return 0;
  }
  
  void picolcd_exit_backlight(struct picolcd_data *data)
  {
  	struct backlight_device *bdev = data->backlight;
  
  	data->backlight = NULL;
  	backlight_device_unregister(bdev);
  }
  
  int picolcd_resume_backlight(struct picolcd_data *data)
  {
  	if (!data->backlight)
  		return 0;
  	return picolcd_set_brightness(data->backlight);
  }
  
  #ifdef CONFIG_PM
  void picolcd_suspend_backlight(struct picolcd_data *data)
  {
  	int bl_power = data->lcd_power;
  	if (!data->backlight)
  		return;
  
  	data->backlight->props.power = FB_BLANK_POWERDOWN;
  	picolcd_set_brightness(data->backlight);
  	data->lcd_power = data->backlight->props.power = bl_power;
  }
  #endif /* CONFIG_PM */