xref: /linux/drivers/hid/hid-picolcd_leds.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
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 
25 #include <linux/fb.h>
26 #include <linux/vmalloc.h>
27 #include <linux/backlight.h>
28 #include <linux/lcd.h>
29 
30 #include <linux/leds.h>
31 
32 #include <linux/seq_file.h>
33 #include <linux/debugfs.h>
34 
35 #include <linux/completion.h>
36 #include <linux/uaccess.h>
37 #include <linux/module.h>
38 
39 #include "hid-picolcd.h"
40 
41 
42 void picolcd_leds_set(struct picolcd_data *data)
43 {
44 	struct hid_report *report;
45 	unsigned long flags;
46 
47 	if (!data->led[0])
48 		return;
49 	report = picolcd_out_report(REPORT_LED_STATE, data->hdev);
50 	if (!report || report->maxfield != 1 || report->field[0]->report_count != 1)
51 		return;
52 
53 	spin_lock_irqsave(&data->lock, flags);
54 	hid_set_field(report->field[0], 0, data->led_state);
55 	if (!(data->status & PICOLCD_FAILED))
56 		hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT);
57 	spin_unlock_irqrestore(&data->lock, flags);
58 }
59 
60 static void picolcd_led_set_brightness(struct led_classdev *led_cdev,
61 			enum led_brightness value)
62 {
63 	struct device *dev;
64 	struct hid_device *hdev;
65 	struct picolcd_data *data;
66 	int i, state = 0;
67 
68 	dev  = led_cdev->dev->parent;
69 	hdev = to_hid_device(dev);
70 	data = hid_get_drvdata(hdev);
71 	if (!data)
72 		return;
73 	for (i = 0; i < 8; i++) {
74 		if (led_cdev != data->led[i])
75 			continue;
76 		state = (data->led_state >> i) & 1;
77 		if (value == LED_OFF && state) {
78 			data->led_state &= ~(1 << i);
79 			picolcd_leds_set(data);
80 		} else if (value != LED_OFF && !state) {
81 			data->led_state |= 1 << i;
82 			picolcd_leds_set(data);
83 		}
84 		break;
85 	}
86 }
87 
88 static enum led_brightness picolcd_led_get_brightness(struct led_classdev *led_cdev)
89 {
90 	struct device *dev;
91 	struct hid_device *hdev;
92 	struct picolcd_data *data;
93 	int i, value = 0;
94 
95 	dev  = led_cdev->dev->parent;
96 	hdev = to_hid_device(dev);
97 	data = hid_get_drvdata(hdev);
98 	for (i = 0; i < 8; i++)
99 		if (led_cdev == data->led[i]) {
100 			value = (data->led_state >> i) & 1;
101 			break;
102 		}
103 	return value ? LED_FULL : LED_OFF;
104 }
105 
106 int picolcd_init_leds(struct picolcd_data *data, struct hid_report *report)
107 {
108 	struct device *dev = &data->hdev->dev;
109 	struct led_classdev *led;
110 	size_t name_sz = strlen(dev_name(dev)) + 8;
111 	char *name;
112 	int i, ret = 0;
113 
114 	if (!report)
115 		return -ENODEV;
116 	if (report->maxfield != 1 || report->field[0]->report_count != 1 ||
117 			report->field[0]->report_size != 8) {
118 		dev_err(dev, "unsupported LED_STATE report");
119 		return -EINVAL;
120 	}
121 
122 	for (i = 0; i < 8; i++) {
123 		led = kzalloc(sizeof(struct led_classdev)+name_sz, GFP_KERNEL);
124 		if (!led) {
125 			dev_err(dev, "can't allocate memory for LED %d\n", i);
126 			ret = -ENOMEM;
127 			goto err;
128 		}
129 		name = (void *)(&led[1]);
130 		snprintf(name, name_sz, "%s::GPO%d", dev_name(dev), i);
131 		led->name = name;
132 		led->brightness = 0;
133 		led->max_brightness = 1;
134 		led->brightness_get = picolcd_led_get_brightness;
135 		led->brightness_set = picolcd_led_set_brightness;
136 
137 		data->led[i] = led;
138 		ret = led_classdev_register(dev, data->led[i]);
139 		if (ret) {
140 			data->led[i] = NULL;
141 			kfree(led);
142 			dev_err(dev, "can't register LED %d\n", i);
143 			goto err;
144 		}
145 	}
146 	return 0;
147 err:
148 	for (i = 0; i < 8; i++)
149 		if (data->led[i]) {
150 			led = data->led[i];
151 			data->led[i] = NULL;
152 			led_classdev_unregister(led);
153 			kfree(led);
154 		}
155 	return ret;
156 }
157 
158 void picolcd_exit_leds(struct picolcd_data *data)
159 {
160 	struct led_classdev *led;
161 	int i;
162 
163 	for (i = 0; i < 8; i++) {
164 		led = data->led[i];
165 		data->led[i] = NULL;
166 		if (!led)
167 			continue;
168 		led_classdev_unregister(led);
169 		kfree(led);
170 	}
171 }
172 
173 
174