1 /***************************************************************************
2 * Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org> *
3 * *
4 * Based on Logitech G13 driver (v0.4) *
5 * Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu> *
6 * *
7 * This program is free software: you can redistribute it and/or modify *
8 * it under the terms of the GNU General Public License as published by *
9 * the Free Software Foundation, version 2 of the License. *
10 * *
11 * This driver is distributed in the hope that it will be useful, but *
12 * WITHOUT ANY WARRANTY; without even the implied warranty of *
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU *
14 * General Public License for more details. *
15 * *
16 * You should have received a copy of the GNU General Public License *
17 * along with this software. If not see <http://www.gnu.org/licenses/>. *
18 ***************************************************************************/
19
20 #include <linux/hid.h>
21
22 #include <linux/fb.h>
23 #include <linux/lcd.h>
24
25 #include "hid-picolcd.h"
26
27 /*
28 * lcd class device
29 */
picolcd_get_contrast(struct lcd_device * ldev)30 static int picolcd_get_contrast(struct lcd_device *ldev)
31 {
32 struct picolcd_data *data = lcd_get_data(ldev);
33 return data->lcd_contrast;
34 }
35
picolcd_set_contrast(struct lcd_device * ldev,int contrast)36 static int picolcd_set_contrast(struct lcd_device *ldev, int contrast)
37 {
38 struct picolcd_data *data = lcd_get_data(ldev);
39 struct hid_report *report = picolcd_out_report(REPORT_CONTRAST, data->hdev);
40 unsigned long flags;
41
42 if (!report || report->maxfield != 1 || report->field[0]->report_count != 1)
43 return -ENODEV;
44
45 data->lcd_contrast = contrast & 0x0ff;
46 spin_lock_irqsave(&data->lock, flags);
47 hid_set_field(report->field[0], 0, data->lcd_contrast);
48 if (!(data->status & PICOLCD_FAILED))
49 hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT);
50 spin_unlock_irqrestore(&data->lock, flags);
51 return 0;
52 }
53
picolcd_check_lcd_fb(struct lcd_device * ldev,struct fb_info * fb)54 static int picolcd_check_lcd_fb(struct lcd_device *ldev, struct fb_info *fb)
55 {
56 return fb && fb == picolcd_fbinfo((struct picolcd_data *)lcd_get_data(ldev));
57 }
58
59 static struct lcd_ops picolcd_lcdops = {
60 .get_contrast = picolcd_get_contrast,
61 .set_contrast = picolcd_set_contrast,
62 .check_fb = picolcd_check_lcd_fb,
63 };
64
picolcd_init_lcd(struct picolcd_data * data,struct hid_report * report)65 int picolcd_init_lcd(struct picolcd_data *data, struct hid_report *report)
66 {
67 struct device *dev = &data->hdev->dev;
68 struct lcd_device *ldev;
69
70 if (!report)
71 return -ENODEV;
72 if (report->maxfield != 1 || report->field[0]->report_count != 1 ||
73 report->field[0]->report_size != 8) {
74 dev_err(dev, "unsupported CONTRAST report");
75 return -EINVAL;
76 }
77
78 ldev = lcd_device_register(dev_name(dev), dev, data, &picolcd_lcdops);
79 if (IS_ERR(ldev)) {
80 dev_err(dev, "failed to register LCD\n");
81 return PTR_ERR(ldev);
82 }
83 ldev->props.max_contrast = 0x0ff;
84 data->lcd_contrast = 0xe5;
85 data->lcd = ldev;
86 picolcd_set_contrast(ldev, 0xe5);
87 return 0;
88 }
89
picolcd_exit_lcd(struct picolcd_data * data)90 void picolcd_exit_lcd(struct picolcd_data *data)
91 {
92 struct lcd_device *ldev = data->lcd;
93
94 data->lcd = NULL;
95 lcd_device_unregister(ldev);
96 }
97
picolcd_resume_lcd(struct picolcd_data * data)98 int picolcd_resume_lcd(struct picolcd_data *data)
99 {
100 if (!data->lcd)
101 return 0;
102 return picolcd_set_contrast(data->lcd, data->lcd_contrast);
103 }
104
105