1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /***************************************************************************
3*4882a593Smuzhiyun * Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org> *
4*4882a593Smuzhiyun * *
5*4882a593Smuzhiyun * Based on Logitech G13 driver (v0.4) *
6*4882a593Smuzhiyun * Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu> *
7*4882a593Smuzhiyun * *
8*4882a593Smuzhiyun ***************************************************************************/
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include <linux/hid.h>
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun #include <linux/fb.h>
13*4882a593Smuzhiyun #include <linux/backlight.h>
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun #include "hid-picolcd.h"
16*4882a593Smuzhiyun
picolcd_get_brightness(struct backlight_device * bdev)17*4882a593Smuzhiyun static int picolcd_get_brightness(struct backlight_device *bdev)
18*4882a593Smuzhiyun {
19*4882a593Smuzhiyun struct picolcd_data *data = bl_get_data(bdev);
20*4882a593Smuzhiyun return data->lcd_brightness;
21*4882a593Smuzhiyun }
22*4882a593Smuzhiyun
picolcd_set_brightness(struct backlight_device * bdev)23*4882a593Smuzhiyun static int picolcd_set_brightness(struct backlight_device *bdev)
24*4882a593Smuzhiyun {
25*4882a593Smuzhiyun struct picolcd_data *data = bl_get_data(bdev);
26*4882a593Smuzhiyun struct hid_report *report = picolcd_out_report(REPORT_BRIGHTNESS, data->hdev);
27*4882a593Smuzhiyun unsigned long flags;
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun if (!report || report->maxfield != 1 || report->field[0]->report_count != 1)
30*4882a593Smuzhiyun return -ENODEV;
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun data->lcd_brightness = bdev->props.brightness & 0x0ff;
33*4882a593Smuzhiyun data->lcd_power = bdev->props.power;
34*4882a593Smuzhiyun spin_lock_irqsave(&data->lock, flags);
35*4882a593Smuzhiyun hid_set_field(report->field[0], 0, data->lcd_power == FB_BLANK_UNBLANK ? data->lcd_brightness : 0);
36*4882a593Smuzhiyun if (!(data->status & PICOLCD_FAILED))
37*4882a593Smuzhiyun hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT);
38*4882a593Smuzhiyun spin_unlock_irqrestore(&data->lock, flags);
39*4882a593Smuzhiyun return 0;
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun
picolcd_check_bl_fb(struct backlight_device * bdev,struct fb_info * fb)42*4882a593Smuzhiyun static int picolcd_check_bl_fb(struct backlight_device *bdev, struct fb_info *fb)
43*4882a593Smuzhiyun {
44*4882a593Smuzhiyun return fb && fb == picolcd_fbinfo((struct picolcd_data *)bl_get_data(bdev));
45*4882a593Smuzhiyun }
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun static const struct backlight_ops picolcd_blops = {
48*4882a593Smuzhiyun .update_status = picolcd_set_brightness,
49*4882a593Smuzhiyun .get_brightness = picolcd_get_brightness,
50*4882a593Smuzhiyun .check_fb = picolcd_check_bl_fb,
51*4882a593Smuzhiyun };
52*4882a593Smuzhiyun
picolcd_init_backlight(struct picolcd_data * data,struct hid_report * report)53*4882a593Smuzhiyun int picolcd_init_backlight(struct picolcd_data *data, struct hid_report *report)
54*4882a593Smuzhiyun {
55*4882a593Smuzhiyun struct device *dev = &data->hdev->dev;
56*4882a593Smuzhiyun struct backlight_device *bdev;
57*4882a593Smuzhiyun struct backlight_properties props;
58*4882a593Smuzhiyun if (!report)
59*4882a593Smuzhiyun return -ENODEV;
60*4882a593Smuzhiyun if (report->maxfield != 1 || report->field[0]->report_count != 1 ||
61*4882a593Smuzhiyun report->field[0]->report_size != 8) {
62*4882a593Smuzhiyun dev_err(dev, "unsupported BRIGHTNESS report");
63*4882a593Smuzhiyun return -EINVAL;
64*4882a593Smuzhiyun }
65*4882a593Smuzhiyun
66*4882a593Smuzhiyun memset(&props, 0, sizeof(props));
67*4882a593Smuzhiyun props.type = BACKLIGHT_RAW;
68*4882a593Smuzhiyun props.max_brightness = 0xff;
69*4882a593Smuzhiyun bdev = backlight_device_register(dev_name(dev), dev, data,
70*4882a593Smuzhiyun &picolcd_blops, &props);
71*4882a593Smuzhiyun if (IS_ERR(bdev)) {
72*4882a593Smuzhiyun dev_err(dev, "failed to register backlight\n");
73*4882a593Smuzhiyun return PTR_ERR(bdev);
74*4882a593Smuzhiyun }
75*4882a593Smuzhiyun bdev->props.brightness = 0xff;
76*4882a593Smuzhiyun data->lcd_brightness = 0xff;
77*4882a593Smuzhiyun data->backlight = bdev;
78*4882a593Smuzhiyun picolcd_set_brightness(bdev);
79*4882a593Smuzhiyun return 0;
80*4882a593Smuzhiyun }
81*4882a593Smuzhiyun
picolcd_exit_backlight(struct picolcd_data * data)82*4882a593Smuzhiyun void picolcd_exit_backlight(struct picolcd_data *data)
83*4882a593Smuzhiyun {
84*4882a593Smuzhiyun struct backlight_device *bdev = data->backlight;
85*4882a593Smuzhiyun
86*4882a593Smuzhiyun data->backlight = NULL;
87*4882a593Smuzhiyun backlight_device_unregister(bdev);
88*4882a593Smuzhiyun }
89*4882a593Smuzhiyun
picolcd_resume_backlight(struct picolcd_data * data)90*4882a593Smuzhiyun int picolcd_resume_backlight(struct picolcd_data *data)
91*4882a593Smuzhiyun {
92*4882a593Smuzhiyun if (!data->backlight)
93*4882a593Smuzhiyun return 0;
94*4882a593Smuzhiyun return picolcd_set_brightness(data->backlight);
95*4882a593Smuzhiyun }
96*4882a593Smuzhiyun
97*4882a593Smuzhiyun #ifdef CONFIG_PM
picolcd_suspend_backlight(struct picolcd_data * data)98*4882a593Smuzhiyun void picolcd_suspend_backlight(struct picolcd_data *data)
99*4882a593Smuzhiyun {
100*4882a593Smuzhiyun int bl_power = data->lcd_power;
101*4882a593Smuzhiyun if (!data->backlight)
102*4882a593Smuzhiyun return;
103*4882a593Smuzhiyun
104*4882a593Smuzhiyun data->backlight->props.power = FB_BLANK_POWERDOWN;
105*4882a593Smuzhiyun picolcd_set_brightness(data->backlight);
106*4882a593Smuzhiyun data->lcd_power = data->backlight->props.power = bl_power;
107*4882a593Smuzhiyun }
108*4882a593Smuzhiyun #endif /* CONFIG_PM */
109*4882a593Smuzhiyun
110