1// SPDX-License-Identifier: GPL-2.0-only
2/***************************************************************************
3 *   Copyright (C) 2010-2012 by Bruno Pr��mont <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 */
20static int picolcd_get_contrast(struct lcd_device *ldev)
21{
22	struct picolcd_data *data = lcd_get_data(ldev);
23	return data->lcd_contrast;
24}
25
26static int picolcd_set_contrast(struct lcd_device *ldev, int contrast)
27{
28	struct picolcd_data *data = lcd_get_data(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(&data->lock, flags);
41	return 0;
42}
43
44static 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
49static 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
55int 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(dev_name(dev), dev, data, &picolcd_lcdops);
69	if (IS_ERR(ldev)) {
70		dev_err(dev, "failed to register LCD\n");
71		return PTR_ERR(ldev);
72	}
73	ldev->props.max_contrast = 0x0ff;
74	data->lcd_contrast = 0xe5;
75	data->lcd = ldev;
76	picolcd_set_contrast(ldev, 0xe5);
77	return 0;
78}
79
80void picolcd_exit_lcd(struct picolcd_data *data)
81{
82	struct lcd_device *ldev = data->lcd;
83
84	data->lcd = NULL;
85	lcd_device_unregister(ldev);
86}
87
88int picolcd_resume_lcd(struct picolcd_data *data)
89{
90	if (!data->lcd)
91		return 0;
92	return picolcd_set_contrast(data->lcd, data->lcd_contrast);
93}
94
95