1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /*************************************************************************** |
3 | * Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org> * |
4 | * * |
5 | * Based on Logitech G13 driver (v0.4) * |
6 | * Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu> * |
7 | * * |
8 | ***************************************************************************/ |
9 | |
10 | #include <linux/hid.h> |
11 | |
12 | #include <linux/fb.h> |
13 | #include <linux/lcd.h> |
14 | |
15 | #include "hid-picolcd.h" |
16 | |
17 | /* |
18 | * lcd class device |
19 | */ |
20 | static int picolcd_get_contrast(struct lcd_device *ldev) |
21 | { |
22 | struct picolcd_data *data = lcd_get_data(ld_dev: ldev); |
23 | return data->lcd_contrast; |
24 | } |
25 | |
26 | static int picolcd_set_contrast(struct lcd_device *ldev, int contrast) |
27 | { |
28 | struct picolcd_data *data = lcd_get_data(ld_dev: ldev); |
29 | struct hid_report *report = picolcd_out_report(REPORT_CONTRAST, data->hdev); |
30 | unsigned long flags; |
31 | |
32 | if (!report || report->maxfield != 1 || report->field[0]->report_count != 1) |
33 | return -ENODEV; |
34 | |
35 | data->lcd_contrast = contrast & 0x0ff; |
36 | spin_lock_irqsave(&data->lock, flags); |
37 | hid_set_field(report->field[0], 0, data->lcd_contrast); |
38 | if (!(data->status & PICOLCD_FAILED)) |
39 | hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT); |
40 | spin_unlock_irqrestore(lock: &data->lock, flags); |
41 | return 0; |
42 | } |
43 | |
44 | static int picolcd_check_lcd_fb(struct lcd_device *ldev, struct fb_info *fb) |
45 | { |
46 | return fb && fb == picolcd_fbinfo((struct picolcd_data *)lcd_get_data(ldev)); |
47 | } |
48 | |
49 | static struct lcd_ops picolcd_lcdops = { |
50 | .get_contrast = picolcd_get_contrast, |
51 | .set_contrast = picolcd_set_contrast, |
52 | .check_fb = picolcd_check_lcd_fb, |
53 | }; |
54 | |
55 | int picolcd_init_lcd(struct picolcd_data *data, struct hid_report *report) |
56 | { |
57 | struct device *dev = &data->hdev->dev; |
58 | struct lcd_device *ldev; |
59 | |
60 | if (!report) |
61 | return -ENODEV; |
62 | if (report->maxfield != 1 || report->field[0]->report_count != 1 || |
63 | report->field[0]->report_size != 8) { |
64 | dev_err(dev, "unsupported CONTRAST report" ); |
65 | return -EINVAL; |
66 | } |
67 | |
68 | ldev = lcd_device_register(name: dev_name(dev), parent: dev, devdata: data, ops: &picolcd_lcdops); |
69 | if (IS_ERR(ptr: ldev)) { |
70 | dev_err(dev, "failed to register LCD\n" ); |
71 | return PTR_ERR(ptr: ldev); |
72 | } |
73 | ldev->props.max_contrast = 0x0ff; |
74 | data->lcd_contrast = 0xe5; |
75 | data->lcd = ldev; |
76 | picolcd_set_contrast(ldev, contrast: 0xe5); |
77 | return 0; |
78 | } |
79 | |
80 | void picolcd_exit_lcd(struct picolcd_data *data) |
81 | { |
82 | struct lcd_device *ldev = data->lcd; |
83 | |
84 | data->lcd = NULL; |
85 | lcd_device_unregister(ld: ldev); |
86 | } |
87 | |
88 | int picolcd_resume_lcd(struct picolcd_data *data) |
89 | { |
90 | if (!data->lcd) |
91 | return 0; |
92 | return picolcd_set_contrast(ldev: data->lcd, contrast: data->lcd_contrast); |
93 | } |
94 | |
95 | |