xref: /linux/drivers/hid/hid-picolcd_leds.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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 #include <linux/hid-debug.h>
22 #include <linux/input.h>
23 #include "hid-ids.h"
24 #include "usbhid/usbhid.h"
25 #include <linux/usb.h>
26 
27 #include <linux/fb.h>
28 #include <linux/vmalloc.h>
29 #include <linux/backlight.h>
30 #include <linux/lcd.h>
31 
32 #include <linux/leds.h>
33 
34 #include <linux/seq_file.h>
35 #include <linux/debugfs.h>
36 
37 #include <linux/completion.h>
38 #include <linux/uaccess.h>
39 #include <linux/module.h>
40 
41 #include "hid-picolcd.h"
42 
43 
44 void picolcd_leds_set(struct picolcd_data *data)
45 {
46 	struct hid_report *report;
47 	unsigned long flags;
48 
49 	if (!data->led[0])
50 		return;
51 	report = picolcd_out_report(REPORT_LED_STATE, data->hdev);
52 	if (!report || report->maxfield != 1 || report->field[0]->report_count != 1)
53 		return;
54 
55 	spin_lock_irqsave(&data->lock, flags);
56 	hid_set_field(report->field[0], 0, data->led_state);
57 	if (!(data->status & PICOLCD_FAILED))
58 		usbhid_submit_report(data->hdev, report, USB_DIR_OUT);
59 	spin_unlock_irqrestore(&data->lock, flags);
60 }
61 
62 static void picolcd_led_set_brightness(struct led_classdev *led_cdev,
63 			enum led_brightness value)
64 {
65 	struct device *dev;
66 	struct hid_device *hdev;
67 	struct picolcd_data *data;
68 	int i, state = 0;
69 
70 	dev  = led_cdev->dev->parent;
71 	hdev = container_of(dev, struct hid_device, dev);
72 	data = hid_get_drvdata(hdev);
73 	if (!data)
74 		return;
75 	for (i = 0; i < 8; i++) {
76 		if (led_cdev != data->led[i])
77 			continue;
78 		state = (data->led_state >> i) & 1;
79 		if (value == LED_OFF && state) {
80 			data->led_state &= ~(1 << i);
81 			picolcd_leds_set(data);
82 		} else if (value != LED_OFF && !state) {
83 			data->led_state |= 1 << i;
84 			picolcd_leds_set(data);
85 		}
86 		break;
87 	}
88 }
89 
90 static enum led_brightness picolcd_led_get_brightness(struct led_classdev *led_cdev)
91 {
92 	struct device *dev;
93 	struct hid_device *hdev;
94 	struct picolcd_data *data;
95 	int i, value = 0;
96 
97 	dev  = led_cdev->dev->parent;
98 	hdev = container_of(dev, struct hid_device, dev);
99 	data = hid_get_drvdata(hdev);
100 	for (i = 0; i < 8; i++)
101 		if (led_cdev == data->led[i]) {
102 			value = (data->led_state >> i) & 1;
103 			break;
104 		}
105 	return value ? LED_FULL : LED_OFF;
106 }
107 
108 int picolcd_init_leds(struct picolcd_data *data, struct hid_report *report)
109 {
110 	struct device *dev = &data->hdev->dev;
111 	struct led_classdev *led;
112 	size_t name_sz = strlen(dev_name(dev)) + 8;
113 	char *name;
114 	int i, ret = 0;
115 
116 	if (!report)
117 		return -ENODEV;
118 	if (report->maxfield != 1 || report->field[0]->report_count != 1 ||
119 			report->field[0]->report_size != 8) {
120 		dev_err(dev, "unsupported LED_STATE report");
121 		return -EINVAL;
122 	}
123 
124 	for (i = 0; i < 8; i++) {
125 		led = kzalloc(sizeof(struct led_classdev)+name_sz, GFP_KERNEL);
126 		if (!led) {
127 			dev_err(dev, "can't allocate memory for LED %d\n", i);
128 			ret = -ENOMEM;
129 			goto err;
130 		}
131 		name = (void *)(&led[1]);
132 		snprintf(name, name_sz, "%s::GPO%d", dev_name(dev), i);
133 		led->name = name;
134 		led->brightness = 0;
135 		led->max_brightness = 1;
136 		led->brightness_get = picolcd_led_get_brightness;
137 		led->brightness_set = picolcd_led_set_brightness;
138 
139 		data->led[i] = led;
140 		ret = led_classdev_register(dev, data->led[i]);
141 		if (ret) {
142 			data->led[i] = NULL;
143 			kfree(led);
144 			dev_err(dev, "can't register LED %d\n", i);
145 			goto err;
146 		}
147 	}
148 	return 0;
149 err:
150 	for (i = 0; i < 8; i++)
151 		if (data->led[i]) {
152 			led = data->led[i];
153 			data->led[i] = NULL;
154 			led_classdev_unregister(led);
155 			kfree(led);
156 		}
157 	return ret;
158 }
159 
160 void picolcd_exit_leds(struct picolcd_data *data)
161 {
162 	struct led_classdev *led;
163 	int i;
164 
165 	for (i = 0; i < 8; i++) {
166 		led = data->led[i];
167 		data->led[i] = NULL;
168 		if (!led)
169 			continue;
170 		led_classdev_unregister(led);
171 		kfree(led);
172 	}
173 }
174 
175 
176