This source file includes following definitions.
- input_polldev_queue_work
- input_polled_device_work
- input_open_polled_device
- input_close_polled_device
- input_polldev_get_poll
- input_polldev_set_poll
- input_polldev_get_max
- input_polldev_get_min
- input_allocate_polled_device
- devm_input_polldev_match
- devm_input_polldev_release
- devm_input_polldev_unregister
- devm_input_allocate_polled_device
- input_free_polled_device
- input_register_polled_device
- input_unregister_polled_device
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8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10 #include <linux/jiffies.h>
11 #include <linux/slab.h>
12 #include <linux/mutex.h>
13 #include <linux/workqueue.h>
14 #include <linux/module.h>
15 #include <linux/input-polldev.h>
16
17 MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
18 MODULE_DESCRIPTION("Generic implementation of a polled input device");
19 MODULE_LICENSE("GPL v2");
20
21 static void input_polldev_queue_work(struct input_polled_dev *dev)
22 {
23 unsigned long delay;
24
25 delay = msecs_to_jiffies(dev->poll_interval);
26 if (delay >= HZ)
27 delay = round_jiffies_relative(delay);
28
29 queue_delayed_work(system_freezable_wq, &dev->work, delay);
30 }
31
32 static void input_polled_device_work(struct work_struct *work)
33 {
34 struct input_polled_dev *dev =
35 container_of(work, struct input_polled_dev, work.work);
36
37 dev->poll(dev);
38 input_polldev_queue_work(dev);
39 }
40
41 static int input_open_polled_device(struct input_dev *input)
42 {
43 struct input_polled_dev *dev = input_get_drvdata(input);
44
45 if (dev->open)
46 dev->open(dev);
47
48
49 if (dev->poll_interval > 0) {
50 dev->poll(dev);
51 input_polldev_queue_work(dev);
52 }
53
54 return 0;
55 }
56
57 static void input_close_polled_device(struct input_dev *input)
58 {
59 struct input_polled_dev *dev = input_get_drvdata(input);
60
61 cancel_delayed_work_sync(&dev->work);
62
63 if (dev->close)
64 dev->close(dev);
65 }
66
67
68
69 static ssize_t input_polldev_get_poll(struct device *dev,
70 struct device_attribute *attr, char *buf)
71 {
72 struct input_polled_dev *polldev = dev_get_drvdata(dev);
73
74 return sprintf(buf, "%d\n", polldev->poll_interval);
75 }
76
77 static ssize_t input_polldev_set_poll(struct device *dev,
78 struct device_attribute *attr, const char *buf,
79 size_t count)
80 {
81 struct input_polled_dev *polldev = dev_get_drvdata(dev);
82 struct input_dev *input = polldev->input;
83 unsigned int interval;
84 int err;
85
86 err = kstrtouint(buf, 0, &interval);
87 if (err)
88 return err;
89
90 if (interval < polldev->poll_interval_min)
91 return -EINVAL;
92
93 if (interval > polldev->poll_interval_max)
94 return -EINVAL;
95
96 mutex_lock(&input->mutex);
97
98 polldev->poll_interval = interval;
99
100 if (input->users) {
101 cancel_delayed_work_sync(&polldev->work);
102 if (polldev->poll_interval > 0)
103 input_polldev_queue_work(polldev);
104 }
105
106 mutex_unlock(&input->mutex);
107
108 return count;
109 }
110
111 static DEVICE_ATTR(poll, S_IRUGO | S_IWUSR, input_polldev_get_poll,
112 input_polldev_set_poll);
113
114
115 static ssize_t input_polldev_get_max(struct device *dev,
116 struct device_attribute *attr, char *buf)
117 {
118 struct input_polled_dev *polldev = dev_get_drvdata(dev);
119
120 return sprintf(buf, "%d\n", polldev->poll_interval_max);
121 }
122
123 static DEVICE_ATTR(max, S_IRUGO, input_polldev_get_max, NULL);
124
125 static ssize_t input_polldev_get_min(struct device *dev,
126 struct device_attribute *attr, char *buf)
127 {
128 struct input_polled_dev *polldev = dev_get_drvdata(dev);
129
130 return sprintf(buf, "%d\n", polldev->poll_interval_min);
131 }
132
133 static DEVICE_ATTR(min, S_IRUGO, input_polldev_get_min, NULL);
134
135 static struct attribute *sysfs_attrs[] = {
136 &dev_attr_poll.attr,
137 &dev_attr_max.attr,
138 &dev_attr_min.attr,
139 NULL
140 };
141
142 static struct attribute_group input_polldev_attribute_group = {
143 .attrs = sysfs_attrs
144 };
145
146 static const struct attribute_group *input_polldev_attribute_groups[] = {
147 &input_polldev_attribute_group,
148 NULL
149 };
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156
157 struct input_polled_dev *input_allocate_polled_device(void)
158 {
159 struct input_polled_dev *dev;
160
161 dev = kzalloc(sizeof(struct input_polled_dev), GFP_KERNEL);
162 if (!dev)
163 return NULL;
164
165 dev->input = input_allocate_device();
166 if (!dev->input) {
167 kfree(dev);
168 return NULL;
169 }
170
171 return dev;
172 }
173 EXPORT_SYMBOL(input_allocate_polled_device);
174
175 struct input_polled_devres {
176 struct input_polled_dev *polldev;
177 };
178
179 static int devm_input_polldev_match(struct device *dev, void *res, void *data)
180 {
181 struct input_polled_devres *devres = res;
182
183 return devres->polldev == data;
184 }
185
186 static void devm_input_polldev_release(struct device *dev, void *res)
187 {
188 struct input_polled_devres *devres = res;
189 struct input_polled_dev *polldev = devres->polldev;
190
191 dev_dbg(dev, "%s: dropping reference/freeing %s\n",
192 __func__, dev_name(&polldev->input->dev));
193
194 input_put_device(polldev->input);
195 kfree(polldev);
196 }
197
198 static void devm_input_polldev_unregister(struct device *dev, void *res)
199 {
200 struct input_polled_devres *devres = res;
201 struct input_polled_dev *polldev = devres->polldev;
202
203 dev_dbg(dev, "%s: unregistering device %s\n",
204 __func__, dev_name(&polldev->input->dev));
205 input_unregister_device(polldev->input);
206
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210
211
212 }
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234 struct input_polled_dev *devm_input_allocate_polled_device(struct device *dev)
235 {
236 struct input_polled_dev *polldev;
237 struct input_polled_devres *devres;
238
239 devres = devres_alloc(devm_input_polldev_release, sizeof(*devres),
240 GFP_KERNEL);
241 if (!devres)
242 return NULL;
243
244 polldev = input_allocate_polled_device();
245 if (!polldev) {
246 devres_free(devres);
247 return NULL;
248 }
249
250 polldev->input->dev.parent = dev;
251 polldev->devres_managed = true;
252
253 devres->polldev = polldev;
254 devres_add(dev, devres);
255
256 return polldev;
257 }
258 EXPORT_SYMBOL(devm_input_allocate_polled_device);
259
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266
267 void input_free_polled_device(struct input_polled_dev *dev)
268 {
269 if (dev) {
270 if (dev->devres_managed)
271 WARN_ON(devres_destroy(dev->input->dev.parent,
272 devm_input_polldev_release,
273 devm_input_polldev_match,
274 dev));
275 input_put_device(dev->input);
276 kfree(dev);
277 }
278 }
279 EXPORT_SYMBOL(input_free_polled_device);
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290
291 int input_register_polled_device(struct input_polled_dev *dev)
292 {
293 struct input_polled_devres *devres = NULL;
294 struct input_dev *input = dev->input;
295 int error;
296
297 if (dev->devres_managed) {
298 devres = devres_alloc(devm_input_polldev_unregister,
299 sizeof(*devres), GFP_KERNEL);
300 if (!devres)
301 return -ENOMEM;
302
303 devres->polldev = dev;
304 }
305
306 input_set_drvdata(input, dev);
307 INIT_DELAYED_WORK(&dev->work, input_polled_device_work);
308
309 if (!dev->poll_interval)
310 dev->poll_interval = 500;
311 if (!dev->poll_interval_max)
312 dev->poll_interval_max = dev->poll_interval;
313
314 input->open = input_open_polled_device;
315 input->close = input_close_polled_device;
316
317 input->dev.groups = input_polldev_attribute_groups;
318
319 error = input_register_device(input);
320 if (error) {
321 devres_free(devres);
322 return error;
323 }
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332 input_get_device(input);
333
334 if (dev->devres_managed) {
335 dev_dbg(input->dev.parent, "%s: registering %s with devres.\n",
336 __func__, dev_name(&input->dev));
337 devres_add(input->dev.parent, devres);
338 }
339
340 return 0;
341 }
342 EXPORT_SYMBOL(input_register_polled_device);
343
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352 void input_unregister_polled_device(struct input_polled_dev *dev)
353 {
354 if (dev->devres_managed)
355 WARN_ON(devres_destroy(dev->input->dev.parent,
356 devm_input_polldev_unregister,
357 devm_input_polldev_match,
358 dev));
359
360 input_unregister_device(dev->input);
361 }
362 EXPORT_SYMBOL(input_unregister_polled_device);