Commit | Line | Data |
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847ec80b JC |
1 | /* The industrial I/O core |
2 | * | |
3 | * Copyright (c) 2008 Jonathan Cameron | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify it | |
6 | * under the terms of the GNU General Public License version 2 as published by | |
7 | * the Free Software Foundation. | |
8 | * | |
9 | * Based on elements of hwmon and input subsystems. | |
10 | */ | |
11 | ||
12 | #include <linux/kernel.h> | |
13 | #include <linux/module.h> | |
14 | #include <linux/idr.h> | |
15 | #include <linux/kdev_t.h> | |
16 | #include <linux/err.h> | |
17 | #include <linux/device.h> | |
18 | #include <linux/fs.h> | |
19 | #include <linux/interrupt.h> | |
20 | #include <linux/poll.h> | |
ffc18afa | 21 | #include <linux/sched.h> |
4439c935 | 22 | #include <linux/wait.h> |
847ec80b | 23 | #include <linux/cdev.h> |
5a0e3ad6 | 24 | #include <linux/slab.h> |
847ec80b JC |
25 | #include "iio.h" |
26 | #include "trigger_consumer.h" | |
27 | ||
28 | #define IIO_ID_PREFIX "device" | |
29 | #define IIO_ID_FORMAT IIO_ID_PREFIX "%d" | |
30 | ||
31 | /* IDR to assign each registered device a unique id*/ | |
32 | static DEFINE_IDR(iio_idr); | |
33 | ||
34 | /* IDR for general event identifiers */ | |
35 | static DEFINE_IDR(iio_event_idr); | |
36 | /* IDR to allocate character device minor numbers */ | |
37 | static DEFINE_IDR(iio_chrdev_idr); | |
38 | /* Lock used to protect both of the above */ | |
39 | static DEFINE_SPINLOCK(iio_idr_lock); | |
40 | ||
41 | dev_t iio_devt; | |
42 | EXPORT_SYMBOL(iio_devt); | |
43 | ||
44 | #define IIO_DEV_MAX 256 | |
5aaaeba8 | 45 | struct bus_type iio_bus_type = { |
847ec80b | 46 | .name = "iio", |
847ec80b | 47 | }; |
5aaaeba8 | 48 | EXPORT_SYMBOL(iio_bus_type); |
847ec80b JC |
49 | |
50 | void __iio_change_event(struct iio_detected_event_list *ev, | |
51 | int ev_code, | |
52 | s64 timestamp) | |
53 | { | |
54 | ev->ev.id = ev_code; | |
55 | ev->ev.timestamp = timestamp; | |
56 | } | |
57 | EXPORT_SYMBOL(__iio_change_event); | |
58 | ||
59 | /* Used both in the interrupt line put events and the ring buffer ones */ | |
60 | ||
61 | /* Note that in it's current form someone has to be listening before events | |
62 | * are queued. Hence a client MUST open the chrdev before the ring buffer is | |
63 | * switched on. | |
64 | */ | |
65 | int __iio_push_event(struct iio_event_interface *ev_int, | |
66 | int ev_code, | |
67 | s64 timestamp, | |
68 | struct iio_shared_ev_pointer * | |
69 | shared_pointer_p) | |
70 | { | |
71 | struct iio_detected_event_list *ev; | |
72 | int ret = 0; | |
73 | ||
74 | /* Does anyone care? */ | |
75 | mutex_lock(&ev_int->event_list_lock); | |
76 | if (test_bit(IIO_BUSY_BIT_POS, &ev_int->handler.flags)) { | |
75c80753 JC |
77 | if (ev_int->current_events == ev_int->max_events) { |
78 | mutex_unlock(&ev_int->event_list_lock); | |
847ec80b | 79 | return 0; |
75c80753 | 80 | } |
847ec80b JC |
81 | ev = kmalloc(sizeof(*ev), GFP_KERNEL); |
82 | if (ev == NULL) { | |
83 | ret = -ENOMEM; | |
75c80753 | 84 | mutex_unlock(&ev_int->event_list_lock); |
847ec80b JC |
85 | goto error_ret; |
86 | } | |
87 | ev->ev.id = ev_code; | |
88 | ev->ev.timestamp = timestamp; | |
89 | ev->shared_pointer = shared_pointer_p; | |
90 | if (ev->shared_pointer) | |
91 | shared_pointer_p->ev_p = ev; | |
92 | ||
93 | list_add_tail(&ev->list, &ev_int->det_events.list); | |
94 | ev_int->current_events++; | |
95 | mutex_unlock(&ev_int->event_list_lock); | |
96 | wake_up_interruptible(&ev_int->wait); | |
97 | } else | |
98 | mutex_unlock(&ev_int->event_list_lock); | |
99 | ||
100 | error_ret: | |
101 | return ret; | |
102 | } | |
103 | EXPORT_SYMBOL(__iio_push_event); | |
104 | ||
105 | int iio_push_event(struct iio_dev *dev_info, | |
106 | int ev_line, | |
107 | int ev_code, | |
108 | s64 timestamp) | |
109 | { | |
110 | return __iio_push_event(&dev_info->event_interfaces[ev_line], | |
111 | ev_code, timestamp, NULL); | |
112 | } | |
113 | EXPORT_SYMBOL(iio_push_event); | |
114 | ||
115 | /* Generic interrupt line interrupt handler */ | |
77712e5f | 116 | static irqreturn_t iio_interrupt_handler(int irq, void *_int_info) |
847ec80b JC |
117 | { |
118 | struct iio_interrupt *int_info = _int_info; | |
119 | struct iio_dev *dev_info = int_info->dev_info; | |
120 | struct iio_event_handler_list *p; | |
121 | s64 time_ns; | |
122 | unsigned long flags; | |
123 | ||
124 | spin_lock_irqsave(&int_info->ev_list_lock, flags); | |
125 | if (list_empty(&int_info->ev_list)) { | |
126 | spin_unlock_irqrestore(&int_info->ev_list_lock, flags); | |
127 | return IRQ_NONE; | |
128 | } | |
129 | ||
130 | time_ns = iio_get_time_ns(); | |
131 | /* detect single element list*/ | |
132 | if (list_is_singular(&int_info->ev_list)) { | |
133 | disable_irq_nosync(irq); | |
134 | p = list_first_entry(&int_info->ev_list, | |
135 | struct iio_event_handler_list, | |
136 | list); | |
137 | /* single event handler - maybe shared */ | |
138 | p->handler(dev_info, 1, time_ns, !(p->refcount > 1)); | |
139 | } else | |
140 | list_for_each_entry(p, &int_info->ev_list, list) { | |
141 | disable_irq_nosync(irq); | |
142 | p->handler(dev_info, 1, time_ns, 0); | |
143 | } | |
144 | spin_unlock_irqrestore(&int_info->ev_list_lock, flags); | |
145 | ||
146 | return IRQ_HANDLED; | |
147 | } | |
148 | ||
149 | static struct iio_interrupt *iio_allocate_interrupt(void) | |
150 | { | |
151 | struct iio_interrupt *i = kmalloc(sizeof *i, GFP_KERNEL); | |
152 | if (i) { | |
153 | spin_lock_init(&i->ev_list_lock); | |
154 | INIT_LIST_HEAD(&i->ev_list); | |
155 | } | |
156 | return i; | |
157 | } | |
158 | ||
159 | /* Confirming the validity of supplied irq is left to drivers.*/ | |
160 | int iio_register_interrupt_line(unsigned int irq, | |
161 | struct iio_dev *dev_info, | |
162 | int line_number, | |
163 | unsigned long type, | |
164 | const char *name) | |
165 | { | |
166 | int ret; | |
167 | ||
168 | dev_info->interrupts[line_number] = iio_allocate_interrupt(); | |
169 | if (dev_info->interrupts[line_number] == NULL) { | |
170 | ret = -ENOMEM; | |
171 | goto error_ret; | |
172 | } | |
173 | dev_info->interrupts[line_number]->line_number = line_number; | |
174 | dev_info->interrupts[line_number]->irq = irq; | |
175 | dev_info->interrupts[line_number]->dev_info = dev_info; | |
176 | ||
177 | /* Possibly only request on demand? | |
178 | * Can see this may complicate the handling of interrupts. | |
179 | * However, with this approach we might end up handling lots of | |
180 | * events no-one cares about.*/ | |
181 | ret = request_irq(irq, | |
182 | &iio_interrupt_handler, | |
183 | type, | |
184 | name, | |
185 | dev_info->interrupts[line_number]); | |
186 | ||
187 | error_ret: | |
188 | return ret; | |
189 | } | |
190 | EXPORT_SYMBOL(iio_register_interrupt_line); | |
191 | ||
192 | /* This turns up an awful lot */ | |
193 | ssize_t iio_read_const_attr(struct device *dev, | |
194 | struct device_attribute *attr, | |
195 | char *buf) | |
196 | { | |
197 | return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string); | |
198 | } | |
199 | EXPORT_SYMBOL(iio_read_const_attr); | |
200 | ||
201 | /* Before this runs the interrupt generator must have been disabled */ | |
202 | void iio_unregister_interrupt_line(struct iio_dev *dev_info, int line_number) | |
203 | { | |
204 | /* make sure the interrupt handlers are all done */ | |
205 | flush_scheduled_work(); | |
206 | free_irq(dev_info->interrupts[line_number]->irq, | |
207 | dev_info->interrupts[line_number]); | |
208 | kfree(dev_info->interrupts[line_number]); | |
209 | } | |
210 | EXPORT_SYMBOL(iio_unregister_interrupt_line); | |
211 | ||
212 | /* Reference counted add and remove */ | |
213 | void iio_add_event_to_list(struct iio_event_handler_list *el, | |
214 | struct list_head *head) | |
215 | { | |
216 | unsigned long flags; | |
217 | struct iio_interrupt *inter = to_iio_interrupt(head); | |
218 | ||
219 | /* take mutex to protect this element */ | |
220 | mutex_lock(&el->exist_lock); | |
221 | if (el->refcount == 0) { | |
222 | /* Take the event list spin lock */ | |
223 | spin_lock_irqsave(&inter->ev_list_lock, flags); | |
224 | list_add(&el->list, head); | |
225 | spin_unlock_irqrestore(&inter->ev_list_lock, flags); | |
226 | } | |
227 | el->refcount++; | |
228 | mutex_unlock(&el->exist_lock); | |
229 | } | |
230 | EXPORT_SYMBOL(iio_add_event_to_list); | |
231 | ||
232 | void iio_remove_event_from_list(struct iio_event_handler_list *el, | |
233 | struct list_head *head) | |
234 | { | |
235 | unsigned long flags; | |
236 | struct iio_interrupt *inter = to_iio_interrupt(head); | |
237 | ||
238 | mutex_lock(&el->exist_lock); | |
239 | el->refcount--; | |
240 | if (el->refcount == 0) { | |
241 | /* Take the event list spin lock */ | |
242 | spin_lock_irqsave(&inter->ev_list_lock, flags); | |
243 | list_del_init(&el->list); | |
244 | spin_unlock_irqrestore(&inter->ev_list_lock, flags); | |
245 | } | |
246 | mutex_unlock(&el->exist_lock); | |
247 | } | |
248 | EXPORT_SYMBOL(iio_remove_event_from_list); | |
249 | ||
77712e5f MB |
250 | static ssize_t iio_event_chrdev_read(struct file *filep, |
251 | char __user *buf, | |
252 | size_t count, | |
253 | loff_t *f_ps) | |
847ec80b JC |
254 | { |
255 | struct iio_event_interface *ev_int = filep->private_data; | |
256 | struct iio_detected_event_list *el; | |
257 | int ret; | |
258 | size_t len; | |
259 | ||
260 | mutex_lock(&ev_int->event_list_lock); | |
261 | if (list_empty(&ev_int->det_events.list)) { | |
262 | if (filep->f_flags & O_NONBLOCK) { | |
263 | ret = -EAGAIN; | |
264 | goto error_mutex_unlock; | |
265 | } | |
266 | mutex_unlock(&ev_int->event_list_lock); | |
267 | /* Blocking on device; waiting for something to be there */ | |
268 | ret = wait_event_interruptible(ev_int->wait, | |
269 | !list_empty(&ev_int | |
270 | ->det_events.list)); | |
271 | if (ret) | |
272 | goto error_ret; | |
273 | /* Single access device so noone else can get the data */ | |
274 | mutex_lock(&ev_int->event_list_lock); | |
275 | } | |
276 | ||
277 | el = list_first_entry(&ev_int->det_events.list, | |
278 | struct iio_detected_event_list, | |
279 | list); | |
280 | len = sizeof el->ev; | |
281 | if (copy_to_user(buf, &(el->ev), len)) { | |
282 | ret = -EFAULT; | |
283 | goto error_mutex_unlock; | |
284 | } | |
285 | list_del(&el->list); | |
286 | ev_int->current_events--; | |
287 | mutex_unlock(&ev_int->event_list_lock); | |
288 | /* | |
289 | * Possible concurency issue if an update of this event is on its way | |
75b16013 JC |
290 | * through. May lead to new event being removed whilst the reported |
291 | * event was the unescalated event. In typical use case this is not a | |
292 | * problem as userspace will say read half the buffer due to a 50% | |
293 | * full event which would make the correct 100% full incorrect anyway. | |
847ec80b | 294 | */ |
75b16013 JC |
295 | if (el->shared_pointer) { |
296 | spin_lock(&el->shared_pointer->lock); | |
847ec80b | 297 | (el->shared_pointer->ev_p) = NULL; |
75b16013 JC |
298 | spin_unlock(&el->shared_pointer->lock); |
299 | } | |
847ec80b JC |
300 | kfree(el); |
301 | ||
302 | return len; | |
303 | ||
304 | error_mutex_unlock: | |
305 | mutex_unlock(&ev_int->event_list_lock); | |
306 | error_ret: | |
307 | ||
308 | return ret; | |
309 | } | |
310 | ||
77712e5f | 311 | static int iio_event_chrdev_release(struct inode *inode, struct file *filep) |
847ec80b JC |
312 | { |
313 | struct iio_handler *hand = iio_cdev_to_handler(inode->i_cdev); | |
314 | struct iio_event_interface *ev_int = hand->private; | |
315 | struct iio_detected_event_list *el, *t; | |
316 | ||
317 | mutex_lock(&ev_int->event_list_lock); | |
318 | clear_bit(IIO_BUSY_BIT_POS, &ev_int->handler.flags); | |
319 | /* | |
320 | * In order to maintain a clean state for reopening, | |
321 | * clear out any awaiting events. The mask will prevent | |
322 | * any new __iio_push_event calls running. | |
323 | */ | |
324 | list_for_each_entry_safe(el, t, &ev_int->det_events.list, list) { | |
325 | list_del(&el->list); | |
326 | kfree(el); | |
327 | } | |
328 | mutex_unlock(&ev_int->event_list_lock); | |
329 | ||
330 | return 0; | |
331 | } | |
332 | ||
77712e5f | 333 | static int iio_event_chrdev_open(struct inode *inode, struct file *filep) |
847ec80b JC |
334 | { |
335 | struct iio_handler *hand = iio_cdev_to_handler(inode->i_cdev); | |
336 | struct iio_event_interface *ev_int = hand->private; | |
337 | ||
338 | mutex_lock(&ev_int->event_list_lock); | |
339 | if (test_and_set_bit(IIO_BUSY_BIT_POS, &hand->flags)) { | |
340 | fops_put(filep->f_op); | |
341 | mutex_unlock(&ev_int->event_list_lock); | |
342 | return -EBUSY; | |
343 | } | |
344 | filep->private_data = hand->private; | |
345 | mutex_unlock(&ev_int->event_list_lock); | |
346 | ||
347 | return 0; | |
348 | } | |
349 | ||
350 | static const struct file_operations iio_event_chrdev_fileops = { | |
351 | .read = iio_event_chrdev_read, | |
352 | .release = iio_event_chrdev_release, | |
353 | .open = iio_event_chrdev_open, | |
354 | .owner = THIS_MODULE, | |
355 | }; | |
356 | ||
357 | static void iio_event_dev_release(struct device *dev) | |
358 | { | |
359 | struct iio_event_interface *ev_int | |
360 | = container_of(dev, struct iio_event_interface, dev); | |
361 | cdev_del(&ev_int->handler.chrdev); | |
362 | iio_device_free_chrdev_minor(MINOR(dev->devt)); | |
363 | }; | |
364 | ||
365 | static struct device_type iio_event_type = { | |
366 | .release = iio_event_dev_release, | |
367 | }; | |
368 | ||
369 | int iio_device_get_chrdev_minor(void) | |
370 | { | |
371 | int ret, val; | |
372 | ||
373 | idr_again: | |
374 | if (unlikely(idr_pre_get(&iio_chrdev_idr, GFP_KERNEL) == 0)) | |
375 | return -ENOMEM; | |
376 | spin_lock(&iio_idr_lock); | |
377 | ret = idr_get_new(&iio_chrdev_idr, NULL, &val); | |
378 | spin_unlock(&iio_idr_lock); | |
379 | if (unlikely(ret == -EAGAIN)) | |
380 | goto idr_again; | |
381 | else if (unlikely(ret)) | |
382 | return ret; | |
383 | if (val > IIO_DEV_MAX) | |
384 | return -ENOMEM; | |
385 | return val; | |
386 | } | |
387 | ||
388 | void iio_device_free_chrdev_minor(int val) | |
389 | { | |
390 | spin_lock(&iio_idr_lock); | |
391 | idr_remove(&iio_chrdev_idr, val); | |
392 | spin_unlock(&iio_idr_lock); | |
393 | } | |
394 | ||
395 | int iio_setup_ev_int(struct iio_event_interface *ev_int, | |
396 | const char *name, | |
397 | struct module *owner, | |
398 | struct device *dev) | |
399 | { | |
400 | int ret, minor; | |
401 | ||
5aaaeba8 | 402 | ev_int->dev.bus = &iio_bus_type; |
847ec80b JC |
403 | ev_int->dev.parent = dev; |
404 | ev_int->dev.type = &iio_event_type; | |
405 | device_initialize(&ev_int->dev); | |
406 | ||
407 | minor = iio_device_get_chrdev_minor(); | |
408 | if (minor < 0) { | |
409 | ret = minor; | |
410 | goto error_device_put; | |
411 | } | |
412 | ev_int->dev.devt = MKDEV(MAJOR(iio_devt), minor); | |
413 | dev_set_name(&ev_int->dev, "%s", name); | |
414 | ||
415 | ret = device_add(&ev_int->dev); | |
416 | if (ret) | |
417 | goto error_free_minor; | |
418 | ||
419 | cdev_init(&ev_int->handler.chrdev, &iio_event_chrdev_fileops); | |
420 | ev_int->handler.chrdev.owner = owner; | |
421 | ||
422 | mutex_init(&ev_int->event_list_lock); | |
423 | /* discussion point - make this variable? */ | |
424 | ev_int->max_events = 10; | |
425 | ev_int->current_events = 0; | |
426 | INIT_LIST_HEAD(&ev_int->det_events.list); | |
427 | init_waitqueue_head(&ev_int->wait); | |
428 | ev_int->handler.private = ev_int; | |
429 | ev_int->handler.flags = 0; | |
430 | ||
431 | ret = cdev_add(&ev_int->handler.chrdev, ev_int->dev.devt, 1); | |
432 | if (ret) | |
433 | goto error_unreg_device; | |
434 | ||
435 | return 0; | |
436 | ||
437 | error_unreg_device: | |
438 | device_unregister(&ev_int->dev); | |
439 | error_free_minor: | |
440 | iio_device_free_chrdev_minor(minor); | |
441 | error_device_put: | |
442 | put_device(&ev_int->dev); | |
443 | ||
444 | return ret; | |
445 | } | |
446 | ||
447 | void iio_free_ev_int(struct iio_event_interface *ev_int) | |
448 | { | |
449 | device_unregister(&ev_int->dev); | |
450 | put_device(&ev_int->dev); | |
451 | } | |
452 | ||
453 | static int __init iio_dev_init(void) | |
454 | { | |
455 | int err; | |
456 | ||
457 | err = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio"); | |
458 | if (err < 0) | |
459 | printk(KERN_ERR "%s: failed to allocate char dev region\n", | |
460 | __FILE__); | |
461 | ||
462 | return err; | |
463 | } | |
464 | ||
465 | static void __exit iio_dev_exit(void) | |
466 | { | |
467 | if (iio_devt) | |
468 | unregister_chrdev_region(iio_devt, IIO_DEV_MAX); | |
469 | } | |
470 | ||
471 | static int __init iio_init(void) | |
472 | { | |
473 | int ret; | |
474 | ||
5aaaeba8 JC |
475 | /* Register sysfs bus */ |
476 | ret = bus_register(&iio_bus_type); | |
847ec80b JC |
477 | if (ret < 0) { |
478 | printk(KERN_ERR | |
5aaaeba8 | 479 | "%s could not register bus type\n", |
847ec80b JC |
480 | __FILE__); |
481 | goto error_nothing; | |
482 | } | |
483 | ||
484 | ret = iio_dev_init(); | |
485 | if (ret < 0) | |
5aaaeba8 | 486 | goto error_unregister_bus_type; |
847ec80b JC |
487 | |
488 | return 0; | |
489 | ||
5aaaeba8 JC |
490 | error_unregister_bus_type: |
491 | bus_unregister(&iio_bus_type); | |
847ec80b JC |
492 | error_nothing: |
493 | return ret; | |
494 | } | |
495 | ||
496 | static void __exit iio_exit(void) | |
497 | { | |
498 | iio_dev_exit(); | |
5aaaeba8 | 499 | bus_unregister(&iio_bus_type); |
847ec80b JC |
500 | } |
501 | ||
502 | static int iio_device_register_sysfs(struct iio_dev *dev_info) | |
503 | { | |
504 | int ret = 0; | |
505 | ||
506 | ret = sysfs_create_group(&dev_info->dev.kobj, dev_info->attrs); | |
507 | if (ret) { | |
508 | dev_err(dev_info->dev.parent, | |
509 | "Failed to register sysfs hooks\n"); | |
510 | goto error_ret; | |
511 | } | |
512 | ||
513 | if (dev_info->scan_el_attrs) { | |
514 | ret = sysfs_create_group(&dev_info->dev.kobj, | |
515 | dev_info->scan_el_attrs); | |
516 | if (ret) | |
517 | dev_err(&dev_info->dev, | |
518 | "Failed to add sysfs scan els\n"); | |
519 | } | |
520 | ||
521 | error_ret: | |
522 | return ret; | |
523 | } | |
524 | ||
525 | static void iio_device_unregister_sysfs(struct iio_dev *dev_info) | |
526 | { | |
527 | if (dev_info->scan_el_attrs) | |
528 | sysfs_remove_group(&dev_info->dev.kobj, | |
529 | dev_info->scan_el_attrs); | |
530 | ||
531 | sysfs_remove_group(&dev_info->dev.kobj, dev_info->attrs); | |
532 | } | |
533 | ||
f3cdc285 | 534 | /* Return a negative errno on failure */ |
847ec80b JC |
535 | int iio_get_new_idr_val(struct idr *this_idr) |
536 | { | |
537 | int ret; | |
538 | int val; | |
539 | ||
540 | idr_again: | |
541 | if (unlikely(idr_pre_get(this_idr, GFP_KERNEL) == 0)) | |
542 | return -ENOMEM; | |
543 | ||
544 | spin_lock(&iio_idr_lock); | |
545 | ret = idr_get_new(this_idr, NULL, &val); | |
546 | spin_unlock(&iio_idr_lock); | |
547 | if (unlikely(ret == -EAGAIN)) | |
548 | goto idr_again; | |
549 | else if (unlikely(ret)) | |
550 | return ret; | |
551 | ||
552 | return val; | |
553 | } | |
554 | EXPORT_SYMBOL(iio_get_new_idr_val); | |
555 | ||
556 | void iio_free_idr_val(struct idr *this_idr, int id) | |
557 | { | |
558 | spin_lock(&iio_idr_lock); | |
559 | idr_remove(this_idr, id); | |
560 | spin_unlock(&iio_idr_lock); | |
561 | } | |
562 | EXPORT_SYMBOL(iio_free_idr_val); | |
563 | ||
564 | static int iio_device_register_id(struct iio_dev *dev_info, | |
565 | struct idr *this_idr) | |
566 | { | |
567 | ||
568 | dev_info->id = iio_get_new_idr_val(&iio_idr); | |
569 | if (dev_info->id < 0) | |
570 | return dev_info->id; | |
571 | return 0; | |
572 | } | |
573 | ||
574 | static void iio_device_unregister_id(struct iio_dev *dev_info) | |
575 | { | |
576 | iio_free_idr_val(&iio_idr, dev_info->id); | |
577 | } | |
578 | ||
579 | static inline int __iio_add_event_config_attrs(struct iio_dev *dev_info, int i) | |
580 | { | |
581 | int ret; | |
582 | /*p for adding, q for removing */ | |
583 | struct attribute **attrp, **attrq; | |
584 | ||
585 | if (dev_info->event_conf_attrs && dev_info->event_conf_attrs[i].attrs) { | |
586 | attrp = dev_info->event_conf_attrs[i].attrs; | |
587 | while (*attrp) { | |
588 | ret = sysfs_add_file_to_group(&dev_info->dev.kobj, | |
589 | *attrp, | |
590 | dev_info | |
591 | ->event_attrs[i].name); | |
592 | if (ret) | |
593 | goto error_ret; | |
594 | attrp++; | |
595 | } | |
596 | } | |
597 | return 0; | |
598 | ||
599 | error_ret: | |
600 | attrq = dev_info->event_conf_attrs[i].attrs; | |
601 | while (attrq != attrp) { | |
602 | sysfs_remove_file_from_group(&dev_info->dev.kobj, | |
603 | *attrq, | |
604 | dev_info->event_attrs[i].name); | |
605 | attrq++; | |
606 | } | |
607 | ||
608 | return ret; | |
609 | } | |
610 | ||
611 | static inline int __iio_remove_event_config_attrs(struct iio_dev *dev_info, | |
612 | int i) | |
613 | { | |
614 | struct attribute **attrq; | |
615 | ||
616 | if (dev_info->event_conf_attrs | |
617 | && dev_info->event_conf_attrs[i].attrs) { | |
618 | attrq = dev_info->event_conf_attrs[i].attrs; | |
619 | while (*attrq) { | |
620 | sysfs_remove_file_from_group(&dev_info->dev.kobj, | |
621 | *attrq, | |
622 | dev_info | |
623 | ->event_attrs[i].name); | |
624 | attrq++; | |
625 | } | |
626 | } | |
627 | ||
628 | return 0; | |
629 | } | |
630 | ||
631 | static int iio_device_register_eventset(struct iio_dev *dev_info) | |
632 | { | |
633 | int ret = 0, i, j; | |
634 | ||
635 | if (dev_info->num_interrupt_lines == 0) | |
636 | return 0; | |
637 | ||
638 | dev_info->event_interfaces = | |
639 | kzalloc(sizeof(struct iio_event_interface) | |
640 | *dev_info->num_interrupt_lines, | |
641 | GFP_KERNEL); | |
642 | if (dev_info->event_interfaces == NULL) { | |
643 | ret = -ENOMEM; | |
644 | goto error_ret; | |
645 | } | |
646 | ||
647 | dev_info->interrupts = kzalloc(sizeof(struct iio_interrupt *) | |
648 | *dev_info->num_interrupt_lines, | |
649 | GFP_KERNEL); | |
650 | if (dev_info->interrupts == NULL) { | |
651 | ret = -ENOMEM; | |
652 | goto error_free_event_interfaces; | |
653 | } | |
654 | ||
655 | for (i = 0; i < dev_info->num_interrupt_lines; i++) { | |
656 | dev_info->event_interfaces[i].owner = dev_info->driver_module; | |
657 | ret = iio_get_new_idr_val(&iio_event_idr); | |
a8947fcf | 658 | if (ret < 0) |
847ec80b JC |
659 | goto error_free_setup_ev_ints; |
660 | else | |
661 | dev_info->event_interfaces[i].id = ret; | |
662 | ||
663 | snprintf(dev_info->event_interfaces[i]._name, 20, | |
ba5c6fba JC |
664 | "%s:event%d", |
665 | dev_name(&dev_info->dev), | |
666 | dev_info->event_interfaces[i].id); | |
847ec80b JC |
667 | |
668 | ret = iio_setup_ev_int(&dev_info->event_interfaces[i], | |
669 | (const char *)(dev_info | |
670 | ->event_interfaces[i] | |
671 | ._name), | |
672 | dev_info->driver_module, | |
673 | &dev_info->dev); | |
674 | if (ret) { | |
675 | dev_err(&dev_info->dev, | |
676 | "Could not get chrdev interface\n"); | |
677 | iio_free_idr_val(&iio_event_idr, | |
678 | dev_info->event_interfaces[i].id); | |
679 | goto error_free_setup_ev_ints; | |
680 | } | |
847ec80b | 681 | |
5cba220b JC |
682 | dev_set_drvdata(&dev_info->event_interfaces[i].dev, |
683 | (void *)dev_info); | |
684 | ret = sysfs_create_group(&dev_info | |
685 | ->event_interfaces[i] | |
686 | .dev.kobj, | |
687 | &dev_info->event_attrs[i]); | |
688 | ||
847ec80b JC |
689 | if (ret) { |
690 | dev_err(&dev_info->dev, | |
691 | "Failed to register sysfs for event attrs"); | |
692 | goto error_remove_sysfs_interfaces; | |
693 | } | |
694 | } | |
695 | ||
696 | for (i = 0; i < dev_info->num_interrupt_lines; i++) { | |
697 | ret = __iio_add_event_config_attrs(dev_info, i); | |
698 | if (ret) | |
699 | goto error_unregister_config_attrs; | |
700 | } | |
701 | ||
702 | return 0; | |
703 | ||
704 | error_unregister_config_attrs: | |
705 | for (j = 0; j < i; j++) | |
706 | __iio_remove_event_config_attrs(dev_info, i); | |
707 | i = dev_info->num_interrupt_lines - 1; | |
708 | error_remove_sysfs_interfaces: | |
709 | for (j = 0; j < i; j++) | |
5cba220b JC |
710 | sysfs_remove_group(&dev_info |
711 | ->event_interfaces[j].dev.kobj, | |
847ec80b | 712 | &dev_info->event_attrs[j]); |
847ec80b JC |
713 | error_free_setup_ev_ints: |
714 | for (j = 0; j < i; j++) { | |
715 | iio_free_idr_val(&iio_event_idr, | |
5cba220b | 716 | dev_info->event_interfaces[j].id); |
847ec80b JC |
717 | iio_free_ev_int(&dev_info->event_interfaces[j]); |
718 | } | |
719 | kfree(dev_info->interrupts); | |
720 | error_free_event_interfaces: | |
721 | kfree(dev_info->event_interfaces); | |
722 | error_ret: | |
723 | ||
724 | return ret; | |
725 | } | |
726 | ||
727 | static void iio_device_unregister_eventset(struct iio_dev *dev_info) | |
728 | { | |
729 | int i; | |
730 | ||
731 | if (dev_info->num_interrupt_lines == 0) | |
732 | return; | |
733 | for (i = 0; i < dev_info->num_interrupt_lines; i++) | |
5cba220b JC |
734 | sysfs_remove_group(&dev_info |
735 | ->event_interfaces[i].dev.kobj, | |
847ec80b JC |
736 | &dev_info->event_attrs[i]); |
737 | ||
738 | for (i = 0; i < dev_info->num_interrupt_lines; i++) { | |
739 | iio_free_idr_val(&iio_event_idr, | |
740 | dev_info->event_interfaces[i].id); | |
741 | iio_free_ev_int(&dev_info->event_interfaces[i]); | |
742 | } | |
743 | kfree(dev_info->interrupts); | |
744 | kfree(dev_info->event_interfaces); | |
745 | } | |
746 | ||
747 | static void iio_dev_release(struct device *device) | |
748 | { | |
749 | struct iio_dev *dev = to_iio_dev(device); | |
750 | ||
751 | iio_put(); | |
752 | kfree(dev); | |
753 | } | |
754 | ||
755 | static struct device_type iio_dev_type = { | |
756 | .name = "iio_device", | |
757 | .release = iio_dev_release, | |
758 | }; | |
759 | ||
760 | struct iio_dev *iio_allocate_device(void) | |
761 | { | |
762 | struct iio_dev *dev = kzalloc(sizeof *dev, GFP_KERNEL); | |
763 | ||
764 | if (dev) { | |
765 | dev->dev.type = &iio_dev_type; | |
5aaaeba8 | 766 | dev->dev.bus = &iio_bus_type; |
847ec80b JC |
767 | device_initialize(&dev->dev); |
768 | dev_set_drvdata(&dev->dev, (void *)dev); | |
769 | mutex_init(&dev->mlock); | |
770 | iio_get(); | |
771 | } | |
772 | ||
773 | return dev; | |
774 | } | |
775 | EXPORT_SYMBOL(iio_allocate_device); | |
776 | ||
777 | void iio_free_device(struct iio_dev *dev) | |
778 | { | |
779 | if (dev) | |
780 | iio_put_device(dev); | |
781 | } | |
782 | EXPORT_SYMBOL(iio_free_device); | |
783 | ||
784 | int iio_device_register(struct iio_dev *dev_info) | |
785 | { | |
786 | int ret; | |
787 | ||
788 | ret = iio_device_register_id(dev_info, &iio_idr); | |
789 | if (ret) { | |
790 | dev_err(&dev_info->dev, "Failed to get id\n"); | |
791 | goto error_ret; | |
792 | } | |
793 | dev_set_name(&dev_info->dev, "device%d", dev_info->id); | |
794 | ||
795 | ret = device_add(&dev_info->dev); | |
796 | if (ret) | |
797 | goto error_free_idr; | |
798 | ret = iio_device_register_sysfs(dev_info); | |
799 | if (ret) { | |
800 | dev_err(dev_info->dev.parent, | |
801 | "Failed to register sysfs interfaces\n"); | |
802 | goto error_del_device; | |
803 | } | |
804 | ret = iio_device_register_eventset(dev_info); | |
805 | if (ret) { | |
806 | dev_err(dev_info->dev.parent, | |
c849d253 | 807 | "Failed to register event set\n"); |
847ec80b JC |
808 | goto error_free_sysfs; |
809 | } | |
810 | if (dev_info->modes & INDIO_RING_TRIGGERED) | |
811 | iio_device_register_trigger_consumer(dev_info); | |
812 | ||
813 | return 0; | |
814 | ||
815 | error_free_sysfs: | |
816 | iio_device_unregister_sysfs(dev_info); | |
817 | error_del_device: | |
818 | device_del(&dev_info->dev); | |
819 | error_free_idr: | |
820 | iio_device_unregister_id(dev_info); | |
821 | error_ret: | |
822 | return ret; | |
823 | } | |
824 | EXPORT_SYMBOL(iio_device_register); | |
825 | ||
826 | void iio_device_unregister(struct iio_dev *dev_info) | |
827 | { | |
828 | if (dev_info->modes & INDIO_RING_TRIGGERED) | |
829 | iio_device_unregister_trigger_consumer(dev_info); | |
830 | iio_device_unregister_eventset(dev_info); | |
831 | iio_device_unregister_sysfs(dev_info); | |
832 | iio_device_unregister_id(dev_info); | |
833 | device_unregister(&dev_info->dev); | |
834 | } | |
835 | EXPORT_SYMBOL(iio_device_unregister); | |
836 | ||
837 | void iio_put(void) | |
838 | { | |
839 | module_put(THIS_MODULE); | |
840 | } | |
841 | ||
842 | void iio_get(void) | |
843 | { | |
844 | __module_get(THIS_MODULE); | |
845 | } | |
846 | ||
847 | subsys_initcall(iio_init); | |
848 | module_exit(iio_exit); | |
849 | ||
850 | MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>"); | |
851 | MODULE_DESCRIPTION("Industrial I/O core"); | |
852 | MODULE_LICENSE("GPL"); |