Commit | Line | Data |
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0dcd8073 DT |
1 | /* |
2 | * Generic implementation of a polled input device | |
3 | ||
4 | * Copyright (c) 2007 Dmitry Torokhov | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify it | |
7 | * under the terms of the GNU General Public License version 2 as published by | |
8 | * the Free Software Foundation. | |
9 | */ | |
10 | ||
da0c4901 JP |
11 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
12 | ||
0dcd8073 | 13 | #include <linux/jiffies.h> |
5a0e3ad6 | 14 | #include <linux/slab.h> |
0dcd8073 | 15 | #include <linux/mutex.h> |
e490ebdc | 16 | #include <linux/workqueue.h> |
0dcd8073 DT |
17 | #include <linux/input-polldev.h> |
18 | ||
36bd52a4 EP |
19 | MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>"); |
20 | MODULE_DESCRIPTION("Generic implementation of a polled input device"); | |
21 | MODULE_LICENSE("GPL v2"); | |
22 | MODULE_VERSION("0.1"); | |
23 | ||
dad725d0 | 24 | static void input_polldev_queue_work(struct input_polled_dev *dev) |
0dcd8073 | 25 | { |
374766bc | 26 | unsigned long delay; |
0dcd8073 | 27 | |
374766bc SH |
28 | delay = msecs_to_jiffies(dev->poll_interval); |
29 | if (delay >= HZ) | |
30 | delay = round_jiffies_relative(delay); | |
31 | ||
e490ebdc | 32 | queue_delayed_work(system_freezable_wq, &dev->work, delay); |
0dcd8073 DT |
33 | } |
34 | ||
dad725d0 SO |
35 | static void input_polled_device_work(struct work_struct *work) |
36 | { | |
37 | struct input_polled_dev *dev = | |
38 | container_of(work, struct input_polled_dev, work.work); | |
39 | ||
40 | dev->poll(dev); | |
41 | input_polldev_queue_work(dev); | |
42 | } | |
43 | ||
0dcd8073 DT |
44 | static int input_open_polled_device(struct input_dev *input) |
45 | { | |
3797fec1 | 46 | struct input_polled_dev *dev = input_get_drvdata(input); |
0dcd8073 | 47 | |
b0aba1e6 SO |
48 | if (dev->open) |
49 | dev->open(dev); | |
0dcd8073 | 50 | |
11bb4cc7 SO |
51 | /* Only start polling if polling is enabled */ |
52 | if (dev->poll_interval > 0) | |
e490ebdc | 53 | queue_delayed_work(system_freezable_wq, &dev->work, 0); |
0dcd8073 DT |
54 | |
55 | return 0; | |
56 | } | |
57 | ||
58 | static void input_close_polled_device(struct input_dev *input) | |
59 | { | |
3797fec1 | 60 | struct input_polled_dev *dev = input_get_drvdata(input); |
0dcd8073 | 61 | |
374766bc | 62 | cancel_delayed_work_sync(&dev->work); |
b0aba1e6 SO |
63 | |
64 | if (dev->close) | |
65 | dev->close(dev); | |
0dcd8073 DT |
66 | } |
67 | ||
dad725d0 SO |
68 | /* SYSFS interface */ |
69 | ||
70 | static ssize_t input_polldev_get_poll(struct device *dev, | |
71 | struct device_attribute *attr, char *buf) | |
72 | { | |
73 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
74 | ||
75 | return sprintf(buf, "%d\n", polldev->poll_interval); | |
76 | } | |
77 | ||
78 | static ssize_t input_polldev_set_poll(struct device *dev, | |
79 | struct device_attribute *attr, const char *buf, | |
80 | size_t count) | |
81 | { | |
82 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
83 | struct input_dev *input = polldev->input; | |
84 | unsigned long interval; | |
85 | ||
86 | if (strict_strtoul(buf, 0, &interval)) | |
87 | return -EINVAL; | |
88 | ||
89 | if (interval < polldev->poll_interval_min) | |
90 | return -EINVAL; | |
91 | ||
92 | if (interval > polldev->poll_interval_max) | |
93 | return -EINVAL; | |
94 | ||
95 | mutex_lock(&input->mutex); | |
96 | ||
97 | polldev->poll_interval = interval; | |
98 | ||
99 | if (input->users) { | |
100 | cancel_delayed_work_sync(&polldev->work); | |
101 | if (polldev->poll_interval > 0) | |
102 | input_polldev_queue_work(polldev); | |
103 | } | |
104 | ||
105 | mutex_unlock(&input->mutex); | |
106 | ||
107 | return count; | |
108 | } | |
109 | ||
110 | static DEVICE_ATTR(poll, S_IRUGO | S_IWUSR, input_polldev_get_poll, | |
111 | input_polldev_set_poll); | |
112 | ||
113 | ||
114 | static ssize_t input_polldev_get_max(struct device *dev, | |
115 | struct device_attribute *attr, char *buf) | |
116 | { | |
117 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
118 | ||
119 | return sprintf(buf, "%d\n", polldev->poll_interval_max); | |
120 | } | |
121 | ||
122 | static DEVICE_ATTR(max, S_IRUGO, input_polldev_get_max, NULL); | |
123 | ||
124 | static ssize_t input_polldev_get_min(struct device *dev, | |
125 | struct device_attribute *attr, char *buf) | |
126 | { | |
127 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
128 | ||
129 | return sprintf(buf, "%d\n", polldev->poll_interval_min); | |
130 | } | |
131 | ||
132 | static DEVICE_ATTR(min, S_IRUGO, input_polldev_get_min, NULL); | |
133 | ||
134 | static struct attribute *sysfs_attrs[] = { | |
135 | &dev_attr_poll.attr, | |
136 | &dev_attr_max.attr, | |
137 | &dev_attr_min.attr, | |
138 | NULL | |
139 | }; | |
140 | ||
141 | static struct attribute_group input_polldev_attribute_group = { | |
142 | .attrs = sysfs_attrs | |
143 | }; | |
144 | ||
0dcd8073 | 145 | /** |
2546bcc2 | 146 | * input_allocate_polled_device - allocate memory for polled device |
0dcd8073 DT |
147 | * |
148 | * The function allocates memory for a polled device and also | |
149 | * for an input device associated with this polled device. | |
150 | */ | |
151 | struct input_polled_dev *input_allocate_polled_device(void) | |
152 | { | |
153 | struct input_polled_dev *dev; | |
154 | ||
155 | dev = kzalloc(sizeof(struct input_polled_dev), GFP_KERNEL); | |
156 | if (!dev) | |
157 | return NULL; | |
158 | ||
159 | dev->input = input_allocate_device(); | |
160 | if (!dev->input) { | |
161 | kfree(dev); | |
162 | return NULL; | |
163 | } | |
164 | ||
165 | return dev; | |
166 | } | |
167 | EXPORT_SYMBOL(input_allocate_polled_device); | |
168 | ||
169 | /** | |
170 | * input_free_polled_device - free memory allocated for polled device | |
171 | * @dev: device to free | |
172 | * | |
173 | * The function frees memory allocated for polling device and drops | |
36203c4f | 174 | * reference to the associated input device. |
0dcd8073 DT |
175 | */ |
176 | void input_free_polled_device(struct input_polled_dev *dev) | |
177 | { | |
178 | if (dev) { | |
179 | input_free_device(dev->input); | |
180 | kfree(dev); | |
181 | } | |
182 | } | |
183 | EXPORT_SYMBOL(input_free_polled_device); | |
184 | ||
185 | /** | |
186 | * input_register_polled_device - register polled device | |
187 | * @dev: device to register | |
188 | * | |
189 | * The function registers previously initialized polled input device | |
190 | * with input layer. The device should be allocated with call to | |
191 | * input_allocate_polled_device(). Callers should also set up poll() | |
192 | * method and set up capabilities (id, name, phys, bits) of the | |
2546bcc2 | 193 | * corresponding input_dev structure. |
0dcd8073 DT |
194 | */ |
195 | int input_register_polled_device(struct input_polled_dev *dev) | |
196 | { | |
197 | struct input_dev *input = dev->input; | |
dad725d0 | 198 | int error; |
0dcd8073 | 199 | |
3797fec1 | 200 | input_set_drvdata(input, dev); |
0dcd8073 DT |
201 | INIT_DELAYED_WORK(&dev->work, input_polled_device_work); |
202 | if (!dev->poll_interval) | |
203 | dev->poll_interval = 500; | |
dad725d0 SO |
204 | if (!dev->poll_interval_max) |
205 | dev->poll_interval_max = dev->poll_interval; | |
0dcd8073 DT |
206 | input->open = input_open_polled_device; |
207 | input->close = input_close_polled_device; | |
208 | ||
dad725d0 SO |
209 | error = input_register_device(input); |
210 | if (error) | |
211 | return error; | |
212 | ||
213 | error = sysfs_create_group(&input->dev.kobj, | |
214 | &input_polldev_attribute_group); | |
215 | if (error) { | |
216 | input_unregister_device(input); | |
217 | return error; | |
218 | } | |
219 | ||
36203c4f DT |
220 | /* |
221 | * Take extra reference to the underlying input device so | |
222 | * that it survives call to input_unregister_polled_device() | |
223 | * and is deleted only after input_free_polled_device() | |
224 | * has been invoked. This is needed to ease task of freeing | |
225 | * sparse keymaps. | |
226 | */ | |
227 | input_get_device(input); | |
228 | ||
dad725d0 | 229 | return 0; |
0dcd8073 DT |
230 | } |
231 | EXPORT_SYMBOL(input_register_polled_device); | |
232 | ||
233 | /** | |
234 | * input_unregister_polled_device - unregister polled device | |
235 | * @dev: device to unregister | |
236 | * | |
237 | * The function unregisters previously registered polled input | |
238 | * device from input layer. Polling is stopped and device is | |
239 | * ready to be freed with call to input_free_polled_device(). | |
0dcd8073 DT |
240 | */ |
241 | void input_unregister_polled_device(struct input_polled_dev *dev) | |
242 | { | |
dad725d0 SO |
243 | sysfs_remove_group(&dev->input->dev.kobj, |
244 | &input_polldev_attribute_group); | |
245 | ||
0dcd8073 | 246 | input_unregister_device(dev->input); |
0dcd8073 DT |
247 | } |
248 | EXPORT_SYMBOL(input_unregister_polled_device); |