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> |
d2d8442d | 17 | #include <linux/module.h> |
0dcd8073 DT |
18 | #include <linux/input-polldev.h> |
19 | ||
36bd52a4 EP |
20 | MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>"); |
21 | MODULE_DESCRIPTION("Generic implementation of a polled input device"); | |
22 | MODULE_LICENSE("GPL v2"); | |
23 | MODULE_VERSION("0.1"); | |
24 | ||
dad725d0 | 25 | static void input_polldev_queue_work(struct input_polled_dev *dev) |
0dcd8073 | 26 | { |
374766bc | 27 | unsigned long delay; |
0dcd8073 | 28 | |
374766bc SH |
29 | delay = msecs_to_jiffies(dev->poll_interval); |
30 | if (delay >= HZ) | |
31 | delay = round_jiffies_relative(delay); | |
32 | ||
e490ebdc | 33 | queue_delayed_work(system_freezable_wq, &dev->work, delay); |
0dcd8073 DT |
34 | } |
35 | ||
dad725d0 SO |
36 | static void input_polled_device_work(struct work_struct *work) |
37 | { | |
38 | struct input_polled_dev *dev = | |
39 | container_of(work, struct input_polled_dev, work.work); | |
40 | ||
41 | dev->poll(dev); | |
42 | input_polldev_queue_work(dev); | |
43 | } | |
44 | ||
0dcd8073 DT |
45 | static int input_open_polled_device(struct input_dev *input) |
46 | { | |
3797fec1 | 47 | struct input_polled_dev *dev = input_get_drvdata(input); |
0dcd8073 | 48 | |
b0aba1e6 SO |
49 | if (dev->open) |
50 | dev->open(dev); | |
0dcd8073 | 51 | |
11bb4cc7 | 52 | /* Only start polling if polling is enabled */ |
5e3e4eb1 DT |
53 | if (dev->poll_interval > 0) { |
54 | dev->poll(dev); | |
55 | input_polldev_queue_work(dev); | |
56 | } | |
0dcd8073 DT |
57 | |
58 | return 0; | |
59 | } | |
60 | ||
61 | static void input_close_polled_device(struct input_dev *input) | |
62 | { | |
3797fec1 | 63 | struct input_polled_dev *dev = input_get_drvdata(input); |
0dcd8073 | 64 | |
374766bc | 65 | cancel_delayed_work_sync(&dev->work); |
b0aba1e6 SO |
66 | |
67 | if (dev->close) | |
68 | dev->close(dev); | |
0dcd8073 DT |
69 | } |
70 | ||
dad725d0 SO |
71 | /* SYSFS interface */ |
72 | ||
73 | static ssize_t input_polldev_get_poll(struct device *dev, | |
74 | struct device_attribute *attr, char *buf) | |
75 | { | |
76 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
77 | ||
78 | return sprintf(buf, "%d\n", polldev->poll_interval); | |
79 | } | |
80 | ||
81 | static ssize_t input_polldev_set_poll(struct device *dev, | |
82 | struct device_attribute *attr, const char *buf, | |
83 | size_t count) | |
84 | { | |
85 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
86 | struct input_dev *input = polldev->input; | |
76496e7a JD |
87 | unsigned int interval; |
88 | int err; | |
dad725d0 | 89 | |
76496e7a JD |
90 | err = kstrtouint(buf, 0, &interval); |
91 | if (err) | |
92 | return err; | |
dad725d0 SO |
93 | |
94 | if (interval < polldev->poll_interval_min) | |
95 | return -EINVAL; | |
96 | ||
97 | if (interval > polldev->poll_interval_max) | |
98 | return -EINVAL; | |
99 | ||
100 | mutex_lock(&input->mutex); | |
101 | ||
102 | polldev->poll_interval = interval; | |
103 | ||
104 | if (input->users) { | |
105 | cancel_delayed_work_sync(&polldev->work); | |
106 | if (polldev->poll_interval > 0) | |
107 | input_polldev_queue_work(polldev); | |
108 | } | |
109 | ||
110 | mutex_unlock(&input->mutex); | |
111 | ||
112 | return count; | |
113 | } | |
114 | ||
115 | static DEVICE_ATTR(poll, S_IRUGO | S_IWUSR, input_polldev_get_poll, | |
116 | input_polldev_set_poll); | |
117 | ||
118 | ||
119 | static ssize_t input_polldev_get_max(struct device *dev, | |
120 | struct device_attribute *attr, char *buf) | |
121 | { | |
122 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
123 | ||
124 | return sprintf(buf, "%d\n", polldev->poll_interval_max); | |
125 | } | |
126 | ||
127 | static DEVICE_ATTR(max, S_IRUGO, input_polldev_get_max, NULL); | |
128 | ||
129 | static ssize_t input_polldev_get_min(struct device *dev, | |
130 | struct device_attribute *attr, char *buf) | |
131 | { | |
132 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
133 | ||
134 | return sprintf(buf, "%d\n", polldev->poll_interval_min); | |
135 | } | |
136 | ||
137 | static DEVICE_ATTR(min, S_IRUGO, input_polldev_get_min, NULL); | |
138 | ||
139 | static struct attribute *sysfs_attrs[] = { | |
140 | &dev_attr_poll.attr, | |
141 | &dev_attr_max.attr, | |
142 | &dev_attr_min.attr, | |
143 | NULL | |
144 | }; | |
145 | ||
146 | static struct attribute_group input_polldev_attribute_group = { | |
147 | .attrs = sysfs_attrs | |
148 | }; | |
149 | ||
0dcd8073 | 150 | /** |
2546bcc2 | 151 | * input_allocate_polled_device - allocate memory for polled device |
0dcd8073 DT |
152 | * |
153 | * The function allocates memory for a polled device and also | |
154 | * for an input device associated with this polled device. | |
155 | */ | |
156 | struct input_polled_dev *input_allocate_polled_device(void) | |
157 | { | |
158 | struct input_polled_dev *dev; | |
159 | ||
160 | dev = kzalloc(sizeof(struct input_polled_dev), GFP_KERNEL); | |
161 | if (!dev) | |
162 | return NULL; | |
163 | ||
164 | dev->input = input_allocate_device(); | |
165 | if (!dev->input) { | |
166 | kfree(dev); | |
167 | return NULL; | |
168 | } | |
169 | ||
170 | return dev; | |
171 | } | |
172 | EXPORT_SYMBOL(input_allocate_polled_device); | |
173 | ||
174 | /** | |
175 | * input_free_polled_device - free memory allocated for polled device | |
176 | * @dev: device to free | |
177 | * | |
178 | * The function frees memory allocated for polling device and drops | |
36203c4f | 179 | * reference to the associated input device. |
0dcd8073 DT |
180 | */ |
181 | void input_free_polled_device(struct input_polled_dev *dev) | |
182 | { | |
183 | if (dev) { | |
184 | input_free_device(dev->input); | |
185 | kfree(dev); | |
186 | } | |
187 | } | |
188 | EXPORT_SYMBOL(input_free_polled_device); | |
189 | ||
190 | /** | |
191 | * input_register_polled_device - register polled device | |
192 | * @dev: device to register | |
193 | * | |
194 | * The function registers previously initialized polled input device | |
195 | * with input layer. The device should be allocated with call to | |
196 | * input_allocate_polled_device(). Callers should also set up poll() | |
197 | * method and set up capabilities (id, name, phys, bits) of the | |
2546bcc2 | 198 | * corresponding input_dev structure. |
0dcd8073 DT |
199 | */ |
200 | int input_register_polled_device(struct input_polled_dev *dev) | |
201 | { | |
202 | struct input_dev *input = dev->input; | |
dad725d0 | 203 | int error; |
0dcd8073 | 204 | |
3797fec1 | 205 | input_set_drvdata(input, dev); |
0dcd8073 DT |
206 | INIT_DELAYED_WORK(&dev->work, input_polled_device_work); |
207 | if (!dev->poll_interval) | |
208 | dev->poll_interval = 500; | |
dad725d0 SO |
209 | if (!dev->poll_interval_max) |
210 | dev->poll_interval_max = dev->poll_interval; | |
0dcd8073 DT |
211 | input->open = input_open_polled_device; |
212 | input->close = input_close_polled_device; | |
213 | ||
dad725d0 SO |
214 | error = input_register_device(input); |
215 | if (error) | |
216 | return error; | |
217 | ||
218 | error = sysfs_create_group(&input->dev.kobj, | |
219 | &input_polldev_attribute_group); | |
220 | if (error) { | |
221 | input_unregister_device(input); | |
222 | return error; | |
223 | } | |
224 | ||
36203c4f DT |
225 | /* |
226 | * Take extra reference to the underlying input device so | |
227 | * that it survives call to input_unregister_polled_device() | |
228 | * and is deleted only after input_free_polled_device() | |
229 | * has been invoked. This is needed to ease task of freeing | |
230 | * sparse keymaps. | |
231 | */ | |
232 | input_get_device(input); | |
233 | ||
dad725d0 | 234 | return 0; |
0dcd8073 DT |
235 | } |
236 | EXPORT_SYMBOL(input_register_polled_device); | |
237 | ||
238 | /** | |
239 | * input_unregister_polled_device - unregister polled device | |
240 | * @dev: device to unregister | |
241 | * | |
242 | * The function unregisters previously registered polled input | |
243 | * device from input layer. Polling is stopped and device is | |
244 | * ready to be freed with call to input_free_polled_device(). | |
0dcd8073 DT |
245 | */ |
246 | void input_unregister_polled_device(struct input_polled_dev *dev) | |
247 | { | |
dad725d0 SO |
248 | sysfs_remove_group(&dev->input->dev.kobj, |
249 | &input_polldev_attribute_group); | |
250 | ||
0dcd8073 | 251 | input_unregister_device(dev->input); |
0dcd8073 DT |
252 | } |
253 | EXPORT_SYMBOL(input_unregister_polled_device); |