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 | ||
d1fefd5b DT |
150 | static const struct attribute_group *input_polldev_attribute_groups[] = { |
151 | &input_polldev_attribute_group, | |
152 | NULL | |
153 | }; | |
154 | ||
0dcd8073 | 155 | /** |
2546bcc2 | 156 | * input_allocate_polled_device - allocate memory for polled device |
0dcd8073 DT |
157 | * |
158 | * The function allocates memory for a polled device and also | |
159 | * for an input device associated with this polled device. | |
160 | */ | |
161 | struct input_polled_dev *input_allocate_polled_device(void) | |
162 | { | |
163 | struct input_polled_dev *dev; | |
164 | ||
165 | dev = kzalloc(sizeof(struct input_polled_dev), GFP_KERNEL); | |
166 | if (!dev) | |
167 | return NULL; | |
168 | ||
169 | dev->input = input_allocate_device(); | |
170 | if (!dev->input) { | |
171 | kfree(dev); | |
172 | return NULL; | |
173 | } | |
174 | ||
175 | return dev; | |
176 | } | |
177 | EXPORT_SYMBOL(input_allocate_polled_device); | |
178 | ||
bf1de976 DT |
179 | struct input_polled_devres { |
180 | struct input_polled_dev *polldev; | |
181 | }; | |
182 | ||
183 | static int devm_input_polldev_match(struct device *dev, void *res, void *data) | |
184 | { | |
185 | struct input_polled_devres *devres = res; | |
186 | ||
187 | return devres->polldev == data; | |
188 | } | |
189 | ||
190 | static void devm_input_polldev_release(struct device *dev, void *res) | |
191 | { | |
192 | struct input_polled_devres *devres = res; | |
193 | struct input_polled_dev *polldev = devres->polldev; | |
194 | ||
195 | dev_dbg(dev, "%s: dropping reference/freeing %s\n", | |
196 | __func__, dev_name(&polldev->input->dev)); | |
197 | ||
198 | input_put_device(polldev->input); | |
199 | kfree(polldev); | |
200 | } | |
201 | ||
202 | static void devm_input_polldev_unregister(struct device *dev, void *res) | |
203 | { | |
204 | struct input_polled_devres *devres = res; | |
205 | struct input_polled_dev *polldev = devres->polldev; | |
206 | ||
207 | dev_dbg(dev, "%s: unregistering device %s\n", | |
208 | __func__, dev_name(&polldev->input->dev)); | |
209 | input_unregister_device(polldev->input); | |
210 | ||
211 | /* | |
212 | * Note that we are still holding extra reference to the input | |
213 | * device so it will stick around until devm_input_polldev_release() | |
214 | * is called. | |
215 | */ | |
216 | } | |
217 | ||
218 | /** | |
219 | * devm_input_allocate_polled_device - allocate managed polled device | |
220 | * @dev: device owning the polled device being created | |
221 | * | |
222 | * Returns prepared &struct input_polled_dev or %NULL. | |
223 | * | |
224 | * Managed polled input devices do not need to be explicitly unregistered | |
225 | * or freed as it will be done automatically when owner device unbinds | |
226 | * from * its driver (or binding fails). Once such managed polled device | |
227 | * is allocated, it is ready to be set up and registered in the same | |
228 | * fashion as regular polled input devices (using | |
229 | * input_register_polled_device() function). | |
230 | * | |
231 | * If you want to manually unregister and free such managed polled devices, | |
232 | * it can be still done by calling input_unregister_polled_device() and | |
233 | * input_free_polled_device(), although it is rarely needed. | |
234 | * | |
235 | * NOTE: the owner device is set up as parent of input device and users | |
236 | * should not override it. | |
237 | */ | |
238 | struct input_polled_dev *devm_input_allocate_polled_device(struct device *dev) | |
239 | { | |
240 | struct input_polled_dev *polldev; | |
241 | struct input_polled_devres *devres; | |
242 | ||
243 | devres = devres_alloc(devm_input_polldev_release, sizeof(*devres), | |
244 | GFP_KERNEL); | |
245 | if (!devres) | |
246 | return NULL; | |
247 | ||
248 | polldev = input_allocate_polled_device(); | |
249 | if (!polldev) { | |
250 | devres_free(devres); | |
251 | return NULL; | |
252 | } | |
253 | ||
254 | polldev->input->dev.parent = dev; | |
255 | polldev->devres_managed = true; | |
256 | ||
257 | devres->polldev = polldev; | |
258 | devres_add(dev, devres); | |
259 | ||
260 | return polldev; | |
261 | } | |
262 | EXPORT_SYMBOL(devm_input_allocate_polled_device); | |
263 | ||
0dcd8073 DT |
264 | /** |
265 | * input_free_polled_device - free memory allocated for polled device | |
266 | * @dev: device to free | |
267 | * | |
268 | * The function frees memory allocated for polling device and drops | |
36203c4f | 269 | * reference to the associated input device. |
0dcd8073 DT |
270 | */ |
271 | void input_free_polled_device(struct input_polled_dev *dev) | |
272 | { | |
273 | if (dev) { | |
bf1de976 DT |
274 | if (dev->devres_managed) |
275 | WARN_ON(devres_destroy(dev->input->dev.parent, | |
276 | devm_input_polldev_release, | |
277 | devm_input_polldev_match, | |
278 | dev)); | |
279 | input_put_device(dev->input); | |
0dcd8073 DT |
280 | kfree(dev); |
281 | } | |
282 | } | |
283 | EXPORT_SYMBOL(input_free_polled_device); | |
284 | ||
285 | /** | |
286 | * input_register_polled_device - register polled device | |
287 | * @dev: device to register | |
288 | * | |
289 | * The function registers previously initialized polled input device | |
290 | * with input layer. The device should be allocated with call to | |
291 | * input_allocate_polled_device(). Callers should also set up poll() | |
292 | * method and set up capabilities (id, name, phys, bits) of the | |
2546bcc2 | 293 | * corresponding input_dev structure. |
0dcd8073 DT |
294 | */ |
295 | int input_register_polled_device(struct input_polled_dev *dev) | |
296 | { | |
bf1de976 | 297 | struct input_polled_devres *devres = NULL; |
0dcd8073 | 298 | struct input_dev *input = dev->input; |
dad725d0 | 299 | int error; |
0dcd8073 | 300 | |
bf1de976 DT |
301 | if (dev->devres_managed) { |
302 | devres = devres_alloc(devm_input_polldev_unregister, | |
303 | sizeof(*devres), GFP_KERNEL); | |
304 | if (!devres) | |
305 | return -ENOMEM; | |
306 | ||
307 | devres->polldev = dev; | |
308 | } | |
309 | ||
3797fec1 | 310 | input_set_drvdata(input, dev); |
0dcd8073 | 311 | INIT_DELAYED_WORK(&dev->work, input_polled_device_work); |
d1fefd5b | 312 | |
0dcd8073 DT |
313 | if (!dev->poll_interval) |
314 | dev->poll_interval = 500; | |
dad725d0 SO |
315 | if (!dev->poll_interval_max) |
316 | dev->poll_interval_max = dev->poll_interval; | |
d1fefd5b | 317 | |
0dcd8073 DT |
318 | input->open = input_open_polled_device; |
319 | input->close = input_close_polled_device; | |
320 | ||
d1fefd5b DT |
321 | input->dev.groups = input_polldev_attribute_groups; |
322 | ||
dad725d0 | 323 | error = input_register_device(input); |
bf1de976 DT |
324 | if (error) { |
325 | devres_free(devres); | |
dad725d0 | 326 | return error; |
bf1de976 | 327 | } |
dad725d0 | 328 | |
36203c4f DT |
329 | /* |
330 | * Take extra reference to the underlying input device so | |
331 | * that it survives call to input_unregister_polled_device() | |
332 | * and is deleted only after input_free_polled_device() | |
333 | * has been invoked. This is needed to ease task of freeing | |
334 | * sparse keymaps. | |
335 | */ | |
336 | input_get_device(input); | |
337 | ||
bf1de976 DT |
338 | if (dev->devres_managed) { |
339 | dev_dbg(input->dev.parent, "%s: registering %s with devres.\n", | |
340 | __func__, dev_name(&input->dev)); | |
341 | devres_add(input->dev.parent, devres); | |
342 | } | |
343 | ||
dad725d0 | 344 | return 0; |
0dcd8073 DT |
345 | } |
346 | EXPORT_SYMBOL(input_register_polled_device); | |
347 | ||
348 | /** | |
349 | * input_unregister_polled_device - unregister polled device | |
350 | * @dev: device to unregister | |
351 | * | |
352 | * The function unregisters previously registered polled input | |
353 | * device from input layer. Polling is stopped and device is | |
354 | * ready to be freed with call to input_free_polled_device(). | |
0dcd8073 DT |
355 | */ |
356 | void input_unregister_polled_device(struct input_polled_dev *dev) | |
357 | { | |
bf1de976 DT |
358 | if (dev->devres_managed) |
359 | WARN_ON(devres_destroy(dev->input->dev.parent, | |
360 | devm_input_polldev_unregister, | |
361 | devm_input_polldev_match, | |
362 | dev)); | |
363 | ||
0dcd8073 | 364 | input_unregister_device(dev->input); |
0dcd8073 DT |
365 | } |
366 | EXPORT_SYMBOL(input_unregister_polled_device); |