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"); | |
36bd52a4 | 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 | 51 | /* Only start polling if polling is enabled */ |
5e3e4eb1 DT |
52 | if (dev->poll_interval > 0) { |
53 | dev->poll(dev); | |
54 | input_polldev_queue_work(dev); | |
55 | } | |
0dcd8073 DT |
56 | |
57 | return 0; | |
58 | } | |
59 | ||
60 | static void input_close_polled_device(struct input_dev *input) | |
61 | { | |
3797fec1 | 62 | struct input_polled_dev *dev = input_get_drvdata(input); |
0dcd8073 | 63 | |
374766bc | 64 | cancel_delayed_work_sync(&dev->work); |
b0aba1e6 SO |
65 | |
66 | if (dev->close) | |
67 | dev->close(dev); | |
0dcd8073 DT |
68 | } |
69 | ||
dad725d0 SO |
70 | /* SYSFS interface */ |
71 | ||
72 | static ssize_t input_polldev_get_poll(struct device *dev, | |
73 | struct device_attribute *attr, char *buf) | |
74 | { | |
75 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
76 | ||
77 | return sprintf(buf, "%d\n", polldev->poll_interval); | |
78 | } | |
79 | ||
80 | static ssize_t input_polldev_set_poll(struct device *dev, | |
81 | struct device_attribute *attr, const char *buf, | |
82 | size_t count) | |
83 | { | |
84 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
85 | struct input_dev *input = polldev->input; | |
76496e7a JD |
86 | unsigned int interval; |
87 | int err; | |
dad725d0 | 88 | |
76496e7a JD |
89 | err = kstrtouint(buf, 0, &interval); |
90 | if (err) | |
91 | return err; | |
dad725d0 SO |
92 | |
93 | if (interval < polldev->poll_interval_min) | |
94 | return -EINVAL; | |
95 | ||
96 | if (interval > polldev->poll_interval_max) | |
97 | return -EINVAL; | |
98 | ||
99 | mutex_lock(&input->mutex); | |
100 | ||
101 | polldev->poll_interval = interval; | |
102 | ||
103 | if (input->users) { | |
104 | cancel_delayed_work_sync(&polldev->work); | |
105 | if (polldev->poll_interval > 0) | |
106 | input_polldev_queue_work(polldev); | |
107 | } | |
108 | ||
109 | mutex_unlock(&input->mutex); | |
110 | ||
111 | return count; | |
112 | } | |
113 | ||
114 | static DEVICE_ATTR(poll, S_IRUGO | S_IWUSR, input_polldev_get_poll, | |
115 | input_polldev_set_poll); | |
116 | ||
117 | ||
118 | static ssize_t input_polldev_get_max(struct device *dev, | |
119 | struct device_attribute *attr, char *buf) | |
120 | { | |
121 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
122 | ||
123 | return sprintf(buf, "%d\n", polldev->poll_interval_max); | |
124 | } | |
125 | ||
126 | static DEVICE_ATTR(max, S_IRUGO, input_polldev_get_max, NULL); | |
127 | ||
128 | static ssize_t input_polldev_get_min(struct device *dev, | |
129 | struct device_attribute *attr, char *buf) | |
130 | { | |
131 | struct input_polled_dev *polldev = dev_get_drvdata(dev); | |
132 | ||
133 | return sprintf(buf, "%d\n", polldev->poll_interval_min); | |
134 | } | |
135 | ||
136 | static DEVICE_ATTR(min, S_IRUGO, input_polldev_get_min, NULL); | |
137 | ||
138 | static struct attribute *sysfs_attrs[] = { | |
139 | &dev_attr_poll.attr, | |
140 | &dev_attr_max.attr, | |
141 | &dev_attr_min.attr, | |
142 | NULL | |
143 | }; | |
144 | ||
145 | static struct attribute_group input_polldev_attribute_group = { | |
146 | .attrs = sysfs_attrs | |
147 | }; | |
148 | ||
d1fefd5b DT |
149 | static const struct attribute_group *input_polldev_attribute_groups[] = { |
150 | &input_polldev_attribute_group, | |
151 | NULL | |
152 | }; | |
153 | ||
0dcd8073 | 154 | /** |
2546bcc2 | 155 | * input_allocate_polled_device - allocate memory for polled device |
0dcd8073 DT |
156 | * |
157 | * The function allocates memory for a polled device and also | |
158 | * for an input device associated with this polled device. | |
159 | */ | |
160 | struct input_polled_dev *input_allocate_polled_device(void) | |
161 | { | |
162 | struct input_polled_dev *dev; | |
163 | ||
164 | dev = kzalloc(sizeof(struct input_polled_dev), GFP_KERNEL); | |
165 | if (!dev) | |
166 | return NULL; | |
167 | ||
168 | dev->input = input_allocate_device(); | |
169 | if (!dev->input) { | |
170 | kfree(dev); | |
171 | return NULL; | |
172 | } | |
173 | ||
174 | return dev; | |
175 | } | |
176 | EXPORT_SYMBOL(input_allocate_polled_device); | |
177 | ||
bf1de976 DT |
178 | struct input_polled_devres { |
179 | struct input_polled_dev *polldev; | |
180 | }; | |
181 | ||
182 | static int devm_input_polldev_match(struct device *dev, void *res, void *data) | |
183 | { | |
184 | struct input_polled_devres *devres = res; | |
185 | ||
186 | return devres->polldev == data; | |
187 | } | |
188 | ||
189 | static void devm_input_polldev_release(struct device *dev, void *res) | |
190 | { | |
191 | struct input_polled_devres *devres = res; | |
192 | struct input_polled_dev *polldev = devres->polldev; | |
193 | ||
194 | dev_dbg(dev, "%s: dropping reference/freeing %s\n", | |
195 | __func__, dev_name(&polldev->input->dev)); | |
196 | ||
197 | input_put_device(polldev->input); | |
198 | kfree(polldev); | |
199 | } | |
200 | ||
201 | static void devm_input_polldev_unregister(struct device *dev, void *res) | |
202 | { | |
203 | struct input_polled_devres *devres = res; | |
204 | struct input_polled_dev *polldev = devres->polldev; | |
205 | ||
206 | dev_dbg(dev, "%s: unregistering device %s\n", | |
207 | __func__, dev_name(&polldev->input->dev)); | |
208 | input_unregister_device(polldev->input); | |
209 | ||
210 | /* | |
211 | * Note that we are still holding extra reference to the input | |
212 | * device so it will stick around until devm_input_polldev_release() | |
213 | * is called. | |
214 | */ | |
215 | } | |
216 | ||
217 | /** | |
218 | * devm_input_allocate_polled_device - allocate managed polled device | |
219 | * @dev: device owning the polled device being created | |
220 | * | |
221 | * Returns prepared &struct input_polled_dev or %NULL. | |
222 | * | |
223 | * Managed polled input devices do not need to be explicitly unregistered | |
224 | * or freed as it will be done automatically when owner device unbinds | |
225 | * from * its driver (or binding fails). Once such managed polled device | |
226 | * is allocated, it is ready to be set up and registered in the same | |
227 | * fashion as regular polled input devices (using | |
228 | * input_register_polled_device() function). | |
229 | * | |
230 | * If you want to manually unregister and free such managed polled devices, | |
231 | * it can be still done by calling input_unregister_polled_device() and | |
232 | * input_free_polled_device(), although it is rarely needed. | |
233 | * | |
234 | * NOTE: the owner device is set up as parent of input device and users | |
235 | * should not override it. | |
236 | */ | |
237 | struct input_polled_dev *devm_input_allocate_polled_device(struct device *dev) | |
238 | { | |
239 | struct input_polled_dev *polldev; | |
240 | struct input_polled_devres *devres; | |
241 | ||
242 | devres = devres_alloc(devm_input_polldev_release, sizeof(*devres), | |
243 | GFP_KERNEL); | |
244 | if (!devres) | |
245 | return NULL; | |
246 | ||
247 | polldev = input_allocate_polled_device(); | |
248 | if (!polldev) { | |
249 | devres_free(devres); | |
250 | return NULL; | |
251 | } | |
252 | ||
253 | polldev->input->dev.parent = dev; | |
254 | polldev->devres_managed = true; | |
255 | ||
256 | devres->polldev = polldev; | |
257 | devres_add(dev, devres); | |
258 | ||
259 | return polldev; | |
260 | } | |
261 | EXPORT_SYMBOL(devm_input_allocate_polled_device); | |
262 | ||
0dcd8073 DT |
263 | /** |
264 | * input_free_polled_device - free memory allocated for polled device | |
265 | * @dev: device to free | |
266 | * | |
267 | * The function frees memory allocated for polling device and drops | |
36203c4f | 268 | * reference to the associated input device. |
0dcd8073 DT |
269 | */ |
270 | void input_free_polled_device(struct input_polled_dev *dev) | |
271 | { | |
272 | if (dev) { | |
bf1de976 DT |
273 | if (dev->devres_managed) |
274 | WARN_ON(devres_destroy(dev->input->dev.parent, | |
275 | devm_input_polldev_release, | |
276 | devm_input_polldev_match, | |
277 | dev)); | |
278 | input_put_device(dev->input); | |
0dcd8073 DT |
279 | kfree(dev); |
280 | } | |
281 | } | |
282 | EXPORT_SYMBOL(input_free_polled_device); | |
283 | ||
284 | /** | |
285 | * input_register_polled_device - register polled device | |
286 | * @dev: device to register | |
287 | * | |
288 | * The function registers previously initialized polled input device | |
289 | * with input layer. The device should be allocated with call to | |
290 | * input_allocate_polled_device(). Callers should also set up poll() | |
291 | * method and set up capabilities (id, name, phys, bits) of the | |
2546bcc2 | 292 | * corresponding input_dev structure. |
0dcd8073 DT |
293 | */ |
294 | int input_register_polled_device(struct input_polled_dev *dev) | |
295 | { | |
bf1de976 | 296 | struct input_polled_devres *devres = NULL; |
0dcd8073 | 297 | struct input_dev *input = dev->input; |
dad725d0 | 298 | int error; |
0dcd8073 | 299 | |
bf1de976 DT |
300 | if (dev->devres_managed) { |
301 | devres = devres_alloc(devm_input_polldev_unregister, | |
302 | sizeof(*devres), GFP_KERNEL); | |
303 | if (!devres) | |
304 | return -ENOMEM; | |
305 | ||
306 | devres->polldev = dev; | |
307 | } | |
308 | ||
3797fec1 | 309 | input_set_drvdata(input, dev); |
0dcd8073 | 310 | INIT_DELAYED_WORK(&dev->work, input_polled_device_work); |
d1fefd5b | 311 | |
0dcd8073 DT |
312 | if (!dev->poll_interval) |
313 | dev->poll_interval = 500; | |
dad725d0 SO |
314 | if (!dev->poll_interval_max) |
315 | dev->poll_interval_max = dev->poll_interval; | |
d1fefd5b | 316 | |
0dcd8073 DT |
317 | input->open = input_open_polled_device; |
318 | input->close = input_close_polled_device; | |
319 | ||
d1fefd5b DT |
320 | input->dev.groups = input_polldev_attribute_groups; |
321 | ||
dad725d0 | 322 | error = input_register_device(input); |
bf1de976 DT |
323 | if (error) { |
324 | devres_free(devres); | |
dad725d0 | 325 | return error; |
bf1de976 | 326 | } |
dad725d0 | 327 | |
36203c4f DT |
328 | /* |
329 | * Take extra reference to the underlying input device so | |
330 | * that it survives call to input_unregister_polled_device() | |
331 | * and is deleted only after input_free_polled_device() | |
332 | * has been invoked. This is needed to ease task of freeing | |
333 | * sparse keymaps. | |
334 | */ | |
335 | input_get_device(input); | |
336 | ||
bf1de976 DT |
337 | if (dev->devres_managed) { |
338 | dev_dbg(input->dev.parent, "%s: registering %s with devres.\n", | |
339 | __func__, dev_name(&input->dev)); | |
340 | devres_add(input->dev.parent, devres); | |
341 | } | |
342 | ||
dad725d0 | 343 | return 0; |
0dcd8073 DT |
344 | } |
345 | EXPORT_SYMBOL(input_register_polled_device); | |
346 | ||
347 | /** | |
348 | * input_unregister_polled_device - unregister polled device | |
349 | * @dev: device to unregister | |
350 | * | |
351 | * The function unregisters previously registered polled input | |
352 | * device from input layer. Polling is stopped and device is | |
353 | * ready to be freed with call to input_free_polled_device(). | |
0dcd8073 DT |
354 | */ |
355 | void input_unregister_polled_device(struct input_polled_dev *dev) | |
356 | { | |
bf1de976 DT |
357 | if (dev->devres_managed) |
358 | WARN_ON(devres_destroy(dev->input->dev.parent, | |
359 | devm_input_polldev_unregister, | |
360 | devm_input_polldev_match, | |
361 | dev)); | |
362 | ||
0dcd8073 | 363 | input_unregister_device(dev->input); |
0dcd8073 DT |
364 | } |
365 | EXPORT_SYMBOL(input_unregister_polled_device); |