Commit | Line | Data |
---|---|---|
beafc54c HK |
1 | /* |
2 | * drivers/uio/uio.c | |
3 | * | |
4 | * Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de> | |
5 | * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de> | |
6 | * Copyright(C) 2006, Hans J. Koch <hjk@linutronix.de> | |
7 | * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com> | |
8 | * | |
9 | * Userspace IO | |
10 | * | |
11 | * Base Functions | |
12 | * | |
13 | * Licensed under the GPLv2 only. | |
14 | */ | |
15 | ||
16 | #include <linux/module.h> | |
17 | #include <linux/init.h> | |
18 | #include <linux/poll.h> | |
19 | #include <linux/device.h> | |
5a0e3ad6 | 20 | #include <linux/slab.h> |
beafc54c HK |
21 | #include <linux/mm.h> |
22 | #include <linux/idr.h> | |
d43c36dc | 23 | #include <linux/sched.h> |
beafc54c HK |
24 | #include <linux/string.h> |
25 | #include <linux/kobject.h> | |
26 | #include <linux/uio_driver.h> | |
27 | ||
28 | #define UIO_MAX_DEVICES 255 | |
29 | ||
30 | struct uio_device { | |
31 | struct module *owner; | |
32 | struct device *dev; | |
33 | int minor; | |
34 | atomic_t event; | |
35 | struct fasync_struct *async_queue; | |
36 | wait_queue_head_t wait; | |
37 | int vma_count; | |
38 | struct uio_info *info; | |
81e7c6a6 | 39 | struct kobject *map_dir; |
e70c412e | 40 | struct kobject *portio_dir; |
beafc54c HK |
41 | }; |
42 | ||
43 | static int uio_major; | |
44 | static DEFINE_IDR(uio_idr); | |
4f014691 | 45 | static const struct file_operations uio_fops; |
beafc54c HK |
46 | |
47 | /* UIO class infrastructure */ | |
48 | static struct uio_class { | |
49 | struct kref kref; | |
50 | struct class *class; | |
51 | } *uio_class; | |
52 | ||
0d4a7bc1 JC |
53 | /* Protect idr accesses */ |
54 | static DEFINE_MUTEX(minor_lock); | |
55 | ||
beafc54c HK |
56 | /* |
57 | * attributes | |
58 | */ | |
59 | ||
81e7c6a6 GKH |
60 | struct uio_map { |
61 | struct kobject kobj; | |
62 | struct uio_mem *mem; | |
beafc54c | 63 | }; |
81e7c6a6 | 64 | #define to_map(map) container_of(map, struct uio_map, kobj) |
beafc54c | 65 | |
82057791 HK |
66 | static ssize_t map_name_show(struct uio_mem *mem, char *buf) |
67 | { | |
68 | if (unlikely(!mem->name)) | |
69 | mem->name = ""; | |
70 | ||
71 | return sprintf(buf, "%s\n", mem->name); | |
72 | } | |
73 | ||
4f808bcd | 74 | static ssize_t map_addr_show(struct uio_mem *mem, char *buf) |
beafc54c | 75 | { |
4f808bcd BP |
76 | return sprintf(buf, "0x%lx\n", mem->addr); |
77 | } | |
beafc54c | 78 | |
4f808bcd BP |
79 | static ssize_t map_size_show(struct uio_mem *mem, char *buf) |
80 | { | |
81 | return sprintf(buf, "0x%lx\n", mem->size); | |
beafc54c HK |
82 | } |
83 | ||
e2b39df1 HK |
84 | static ssize_t map_offset_show(struct uio_mem *mem, char *buf) |
85 | { | |
86 | return sprintf(buf, "0x%lx\n", mem->addr & ~PAGE_MASK); | |
87 | } | |
88 | ||
e70c412e | 89 | struct map_sysfs_entry { |
4f808bcd BP |
90 | struct attribute attr; |
91 | ssize_t (*show)(struct uio_mem *, char *); | |
92 | ssize_t (*store)(struct uio_mem *, const char *, size_t); | |
93 | }; | |
94 | ||
82057791 HK |
95 | static struct map_sysfs_entry name_attribute = |
96 | __ATTR(name, S_IRUGO, map_name_show, NULL); | |
e70c412e | 97 | static struct map_sysfs_entry addr_attribute = |
4f808bcd | 98 | __ATTR(addr, S_IRUGO, map_addr_show, NULL); |
e70c412e | 99 | static struct map_sysfs_entry size_attribute = |
4f808bcd | 100 | __ATTR(size, S_IRUGO, map_size_show, NULL); |
e70c412e | 101 | static struct map_sysfs_entry offset_attribute = |
e2b39df1 | 102 | __ATTR(offset, S_IRUGO, map_offset_show, NULL); |
beafc54c | 103 | |
81e7c6a6 | 104 | static struct attribute *attrs[] = { |
82057791 | 105 | &name_attribute.attr, |
4f808bcd | 106 | &addr_attribute.attr, |
81e7c6a6 | 107 | &size_attribute.attr, |
e2b39df1 | 108 | &offset_attribute.attr, |
81e7c6a6 | 109 | NULL, /* need to NULL terminate the list of attributes */ |
beafc54c HK |
110 | }; |
111 | ||
81e7c6a6 GKH |
112 | static void map_release(struct kobject *kobj) |
113 | { | |
114 | struct uio_map *map = to_map(kobj); | |
115 | kfree(map); | |
116 | } | |
117 | ||
4f808bcd BP |
118 | static ssize_t map_type_show(struct kobject *kobj, struct attribute *attr, |
119 | char *buf) | |
120 | { | |
121 | struct uio_map *map = to_map(kobj); | |
122 | struct uio_mem *mem = map->mem; | |
e70c412e | 123 | struct map_sysfs_entry *entry; |
4f808bcd | 124 | |
e70c412e | 125 | entry = container_of(attr, struct map_sysfs_entry, attr); |
4f808bcd BP |
126 | |
127 | if (!entry->show) | |
128 | return -EIO; | |
129 | ||
130 | return entry->show(mem, buf); | |
131 | } | |
132 | ||
52cf25d0 | 133 | static const struct sysfs_ops map_sysfs_ops = { |
4f808bcd BP |
134 | .show = map_type_show, |
135 | }; | |
136 | ||
beafc54c | 137 | static struct kobj_type map_attr_type = { |
81e7c6a6 | 138 | .release = map_release, |
e70c412e | 139 | .sysfs_ops = &map_sysfs_ops, |
81e7c6a6 | 140 | .default_attrs = attrs, |
beafc54c HK |
141 | }; |
142 | ||
e70c412e HK |
143 | struct uio_portio { |
144 | struct kobject kobj; | |
145 | struct uio_port *port; | |
146 | }; | |
147 | #define to_portio(portio) container_of(portio, struct uio_portio, kobj) | |
148 | ||
82057791 HK |
149 | static ssize_t portio_name_show(struct uio_port *port, char *buf) |
150 | { | |
151 | if (unlikely(!port->name)) | |
152 | port->name = ""; | |
153 | ||
154 | return sprintf(buf, "%s\n", port->name); | |
155 | } | |
156 | ||
e70c412e HK |
157 | static ssize_t portio_start_show(struct uio_port *port, char *buf) |
158 | { | |
159 | return sprintf(buf, "0x%lx\n", port->start); | |
160 | } | |
161 | ||
162 | static ssize_t portio_size_show(struct uio_port *port, char *buf) | |
163 | { | |
164 | return sprintf(buf, "0x%lx\n", port->size); | |
165 | } | |
166 | ||
167 | static ssize_t portio_porttype_show(struct uio_port *port, char *buf) | |
168 | { | |
169 | const char *porttypes[] = {"none", "x86", "gpio", "other"}; | |
170 | ||
171 | if ((port->porttype < 0) || (port->porttype > UIO_PORT_OTHER)) | |
172 | return -EINVAL; | |
173 | ||
174 | return sprintf(buf, "port_%s\n", porttypes[port->porttype]); | |
175 | } | |
176 | ||
177 | struct portio_sysfs_entry { | |
178 | struct attribute attr; | |
179 | ssize_t (*show)(struct uio_port *, char *); | |
180 | ssize_t (*store)(struct uio_port *, const char *, size_t); | |
181 | }; | |
182 | ||
82057791 HK |
183 | static struct portio_sysfs_entry portio_name_attribute = |
184 | __ATTR(name, S_IRUGO, portio_name_show, NULL); | |
e70c412e HK |
185 | static struct portio_sysfs_entry portio_start_attribute = |
186 | __ATTR(start, S_IRUGO, portio_start_show, NULL); | |
187 | static struct portio_sysfs_entry portio_size_attribute = | |
188 | __ATTR(size, S_IRUGO, portio_size_show, NULL); | |
189 | static struct portio_sysfs_entry portio_porttype_attribute = | |
190 | __ATTR(porttype, S_IRUGO, portio_porttype_show, NULL); | |
191 | ||
192 | static struct attribute *portio_attrs[] = { | |
82057791 | 193 | &portio_name_attribute.attr, |
e70c412e HK |
194 | &portio_start_attribute.attr, |
195 | &portio_size_attribute.attr, | |
196 | &portio_porttype_attribute.attr, | |
197 | NULL, | |
198 | }; | |
199 | ||
200 | static void portio_release(struct kobject *kobj) | |
201 | { | |
202 | struct uio_portio *portio = to_portio(kobj); | |
203 | kfree(portio); | |
204 | } | |
205 | ||
206 | static ssize_t portio_type_show(struct kobject *kobj, struct attribute *attr, | |
207 | char *buf) | |
208 | { | |
209 | struct uio_portio *portio = to_portio(kobj); | |
210 | struct uio_port *port = portio->port; | |
211 | struct portio_sysfs_entry *entry; | |
212 | ||
213 | entry = container_of(attr, struct portio_sysfs_entry, attr); | |
214 | ||
215 | if (!entry->show) | |
216 | return -EIO; | |
217 | ||
218 | return entry->show(port, buf); | |
219 | } | |
220 | ||
52cf25d0 | 221 | static const struct sysfs_ops portio_sysfs_ops = { |
e70c412e HK |
222 | .show = portio_type_show, |
223 | }; | |
224 | ||
225 | static struct kobj_type portio_attr_type = { | |
226 | .release = portio_release, | |
227 | .sysfs_ops = &portio_sysfs_ops, | |
228 | .default_attrs = portio_attrs, | |
229 | }; | |
230 | ||
beafc54c HK |
231 | static ssize_t show_name(struct device *dev, |
232 | struct device_attribute *attr, char *buf) | |
233 | { | |
234 | struct uio_device *idev = dev_get_drvdata(dev); | |
235 | if (idev) | |
236 | return sprintf(buf, "%s\n", idev->info->name); | |
237 | else | |
238 | return -ENODEV; | |
239 | } | |
240 | static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); | |
241 | ||
242 | static ssize_t show_version(struct device *dev, | |
243 | struct device_attribute *attr, char *buf) | |
244 | { | |
245 | struct uio_device *idev = dev_get_drvdata(dev); | |
246 | if (idev) | |
247 | return sprintf(buf, "%s\n", idev->info->version); | |
248 | else | |
249 | return -ENODEV; | |
250 | } | |
251 | static DEVICE_ATTR(version, S_IRUGO, show_version, NULL); | |
252 | ||
253 | static ssize_t show_event(struct device *dev, | |
254 | struct device_attribute *attr, char *buf) | |
255 | { | |
256 | struct uio_device *idev = dev_get_drvdata(dev); | |
257 | if (idev) | |
258 | return sprintf(buf, "%u\n", | |
259 | (unsigned int)atomic_read(&idev->event)); | |
260 | else | |
261 | return -ENODEV; | |
262 | } | |
263 | static DEVICE_ATTR(event, S_IRUGO, show_event, NULL); | |
264 | ||
265 | static struct attribute *uio_attrs[] = { | |
266 | &dev_attr_name.attr, | |
267 | &dev_attr_version.attr, | |
268 | &dev_attr_event.attr, | |
269 | NULL, | |
270 | }; | |
271 | ||
272 | static struct attribute_group uio_attr_grp = { | |
273 | .attrs = uio_attrs, | |
274 | }; | |
275 | ||
276 | /* | |
277 | * device functions | |
278 | */ | |
279 | static int uio_dev_add_attributes(struct uio_device *idev) | |
280 | { | |
281 | int ret; | |
e70c412e | 282 | int mi, pi; |
beafc54c | 283 | int map_found = 0; |
e70c412e | 284 | int portio_found = 0; |
beafc54c | 285 | struct uio_mem *mem; |
81e7c6a6 | 286 | struct uio_map *map; |
e70c412e HK |
287 | struct uio_port *port; |
288 | struct uio_portio *portio; | |
beafc54c HK |
289 | |
290 | ret = sysfs_create_group(&idev->dev->kobj, &uio_attr_grp); | |
291 | if (ret) | |
292 | goto err_group; | |
293 | ||
294 | for (mi = 0; mi < MAX_UIO_MAPS; mi++) { | |
295 | mem = &idev->info->mem[mi]; | |
296 | if (mem->size == 0) | |
297 | break; | |
298 | if (!map_found) { | |
299 | map_found = 1; | |
81e7c6a6 GKH |
300 | idev->map_dir = kobject_create_and_add("maps", |
301 | &idev->dev->kobj); | |
302 | if (!idev->map_dir) | |
e70c412e | 303 | goto err_map; |
beafc54c | 304 | } |
81e7c6a6 GKH |
305 | map = kzalloc(sizeof(*map), GFP_KERNEL); |
306 | if (!map) | |
e70c412e | 307 | goto err_map; |
f9cb074b | 308 | kobject_init(&map->kobj, &map_attr_type); |
81e7c6a6 GKH |
309 | map->mem = mem; |
310 | mem->map = map; | |
b2d6db58 | 311 | ret = kobject_add(&map->kobj, idev->map_dir, "map%d", mi); |
81e7c6a6 | 312 | if (ret) |
e70c412e | 313 | goto err_map; |
81e7c6a6 | 314 | ret = kobject_uevent(&map->kobj, KOBJ_ADD); |
beafc54c | 315 | if (ret) |
e70c412e HK |
316 | goto err_map; |
317 | } | |
318 | ||
319 | for (pi = 0; pi < MAX_UIO_PORT_REGIONS; pi++) { | |
320 | port = &idev->info->port[pi]; | |
321 | if (port->size == 0) | |
322 | break; | |
323 | if (!portio_found) { | |
324 | portio_found = 1; | |
325 | idev->portio_dir = kobject_create_and_add("portio", | |
326 | &idev->dev->kobj); | |
327 | if (!idev->portio_dir) | |
328 | goto err_portio; | |
329 | } | |
330 | portio = kzalloc(sizeof(*portio), GFP_KERNEL); | |
331 | if (!portio) | |
332 | goto err_portio; | |
333 | kobject_init(&portio->kobj, &portio_attr_type); | |
334 | portio->port = port; | |
335 | port->portio = portio; | |
336 | ret = kobject_add(&portio->kobj, idev->portio_dir, | |
337 | "port%d", pi); | |
338 | if (ret) | |
339 | goto err_portio; | |
340 | ret = kobject_uevent(&portio->kobj, KOBJ_ADD); | |
341 | if (ret) | |
342 | goto err_portio; | |
beafc54c HK |
343 | } |
344 | ||
345 | return 0; | |
346 | ||
e70c412e HK |
347 | err_portio: |
348 | for (pi--; pi >= 0; pi--) { | |
349 | port = &idev->info->port[pi]; | |
350 | portio = port->portio; | |
351 | kobject_put(&portio->kobj); | |
352 | } | |
353 | kobject_put(idev->portio_dir); | |
354 | err_map: | |
beafc54c HK |
355 | for (mi--; mi>=0; mi--) { |
356 | mem = &idev->info->mem[mi]; | |
81e7c6a6 | 357 | map = mem->map; |
c10997f6 | 358 | kobject_put(&map->kobj); |
beafc54c | 359 | } |
c10997f6 | 360 | kobject_put(idev->map_dir); |
beafc54c HK |
361 | sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp); |
362 | err_group: | |
363 | dev_err(idev->dev, "error creating sysfs files (%d)\n", ret); | |
364 | return ret; | |
365 | } | |
366 | ||
367 | static void uio_dev_del_attributes(struct uio_device *idev) | |
368 | { | |
e70c412e | 369 | int i; |
beafc54c | 370 | struct uio_mem *mem; |
e70c412e HK |
371 | struct uio_port *port; |
372 | ||
373 | for (i = 0; i < MAX_UIO_MAPS; i++) { | |
374 | mem = &idev->info->mem[i]; | |
beafc54c HK |
375 | if (mem->size == 0) |
376 | break; | |
c10997f6 | 377 | kobject_put(&mem->map->kobj); |
beafc54c | 378 | } |
c10997f6 | 379 | kobject_put(idev->map_dir); |
e70c412e HK |
380 | |
381 | for (i = 0; i < MAX_UIO_PORT_REGIONS; i++) { | |
382 | port = &idev->info->port[i]; | |
383 | if (port->size == 0) | |
384 | break; | |
385 | kobject_put(&port->portio->kobj); | |
386 | } | |
387 | kobject_put(idev->portio_dir); | |
388 | ||
beafc54c HK |
389 | sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp); |
390 | } | |
391 | ||
392 | static int uio_get_minor(struct uio_device *idev) | |
393 | { | |
beafc54c HK |
394 | int retval = -ENOMEM; |
395 | int id; | |
396 | ||
397 | mutex_lock(&minor_lock); | |
398 | if (idr_pre_get(&uio_idr, GFP_KERNEL) == 0) | |
399 | goto exit; | |
400 | ||
401 | retval = idr_get_new(&uio_idr, idev, &id); | |
402 | if (retval < 0) { | |
403 | if (retval == -EAGAIN) | |
404 | retval = -ENOMEM; | |
405 | goto exit; | |
406 | } | |
407 | idev->minor = id & MAX_ID_MASK; | |
408 | exit: | |
409 | mutex_unlock(&minor_lock); | |
410 | return retval; | |
411 | } | |
412 | ||
413 | static void uio_free_minor(struct uio_device *idev) | |
414 | { | |
0d4a7bc1 | 415 | mutex_lock(&minor_lock); |
beafc54c | 416 | idr_remove(&uio_idr, idev->minor); |
0d4a7bc1 | 417 | mutex_unlock(&minor_lock); |
beafc54c HK |
418 | } |
419 | ||
420 | /** | |
421 | * uio_event_notify - trigger an interrupt event | |
422 | * @info: UIO device capabilities | |
423 | */ | |
424 | void uio_event_notify(struct uio_info *info) | |
425 | { | |
426 | struct uio_device *idev = info->uio_dev; | |
427 | ||
428 | atomic_inc(&idev->event); | |
429 | wake_up_interruptible(&idev->wait); | |
430 | kill_fasync(&idev->async_queue, SIGIO, POLL_IN); | |
431 | } | |
432 | EXPORT_SYMBOL_GPL(uio_event_notify); | |
433 | ||
434 | /** | |
435 | * uio_interrupt - hardware interrupt handler | |
436 | * @irq: IRQ number, can be UIO_IRQ_CYCLIC for cyclic timer | |
437 | * @dev_id: Pointer to the devices uio_device structure | |
438 | */ | |
439 | static irqreturn_t uio_interrupt(int irq, void *dev_id) | |
440 | { | |
441 | struct uio_device *idev = (struct uio_device *)dev_id; | |
442 | irqreturn_t ret = idev->info->handler(irq, idev->info); | |
443 | ||
444 | if (ret == IRQ_HANDLED) | |
445 | uio_event_notify(idev->info); | |
446 | ||
447 | return ret; | |
448 | } | |
449 | ||
450 | struct uio_listener { | |
451 | struct uio_device *dev; | |
452 | s32 event_count; | |
453 | }; | |
454 | ||
455 | static int uio_open(struct inode *inode, struct file *filep) | |
456 | { | |
457 | struct uio_device *idev; | |
458 | struct uio_listener *listener; | |
459 | int ret = 0; | |
460 | ||
0d4a7bc1 | 461 | mutex_lock(&minor_lock); |
beafc54c | 462 | idev = idr_find(&uio_idr, iminor(inode)); |
0d4a7bc1 | 463 | mutex_unlock(&minor_lock); |
fbc8a81d JC |
464 | if (!idev) { |
465 | ret = -ENODEV; | |
466 | goto out; | |
467 | } | |
beafc54c | 468 | |
fbc8a81d JC |
469 | if (!try_module_get(idev->owner)) { |
470 | ret = -ENODEV; | |
471 | goto out; | |
472 | } | |
610ad506 | 473 | |
beafc54c | 474 | listener = kmalloc(sizeof(*listener), GFP_KERNEL); |
610ad506 UKK |
475 | if (!listener) { |
476 | ret = -ENOMEM; | |
477 | goto err_alloc_listener; | |
478 | } | |
beafc54c HK |
479 | |
480 | listener->dev = idev; | |
481 | listener->event_count = atomic_read(&idev->event); | |
482 | filep->private_data = listener; | |
483 | ||
484 | if (idev->info->open) { | |
beafc54c | 485 | ret = idev->info->open(idev->info, inode); |
610ad506 UKK |
486 | if (ret) |
487 | goto err_infoopen; | |
beafc54c | 488 | } |
610ad506 UKK |
489 | return 0; |
490 | ||
491 | err_infoopen: | |
610ad506 | 492 | kfree(listener); |
610ad506 | 493 | |
0d4a7bc1 | 494 | err_alloc_listener: |
610ad506 | 495 | module_put(idev->owner); |
beafc54c | 496 | |
fbc8a81d | 497 | out: |
beafc54c HK |
498 | return ret; |
499 | } | |
500 | ||
501 | static int uio_fasync(int fd, struct file *filep, int on) | |
502 | { | |
503 | struct uio_listener *listener = filep->private_data; | |
504 | struct uio_device *idev = listener->dev; | |
505 | ||
506 | return fasync_helper(fd, filep, on, &idev->async_queue); | |
507 | } | |
508 | ||
509 | static int uio_release(struct inode *inode, struct file *filep) | |
510 | { | |
511 | int ret = 0; | |
512 | struct uio_listener *listener = filep->private_data; | |
513 | struct uio_device *idev = listener->dev; | |
514 | ||
610ad506 | 515 | if (idev->info->release) |
beafc54c | 516 | ret = idev->info->release(idev->info, inode); |
610ad506 UKK |
517 | |
518 | module_put(idev->owner); | |
beafc54c HK |
519 | kfree(listener); |
520 | return ret; | |
521 | } | |
522 | ||
523 | static unsigned int uio_poll(struct file *filep, poll_table *wait) | |
524 | { | |
525 | struct uio_listener *listener = filep->private_data; | |
526 | struct uio_device *idev = listener->dev; | |
527 | ||
528 | if (idev->info->irq == UIO_IRQ_NONE) | |
529 | return -EIO; | |
530 | ||
531 | poll_wait(filep, &idev->wait, wait); | |
532 | if (listener->event_count != atomic_read(&idev->event)) | |
533 | return POLLIN | POLLRDNORM; | |
534 | return 0; | |
535 | } | |
536 | ||
537 | static ssize_t uio_read(struct file *filep, char __user *buf, | |
538 | size_t count, loff_t *ppos) | |
539 | { | |
540 | struct uio_listener *listener = filep->private_data; | |
541 | struct uio_device *idev = listener->dev; | |
542 | DECLARE_WAITQUEUE(wait, current); | |
543 | ssize_t retval; | |
544 | s32 event_count; | |
545 | ||
546 | if (idev->info->irq == UIO_IRQ_NONE) | |
547 | return -EIO; | |
548 | ||
549 | if (count != sizeof(s32)) | |
550 | return -EINVAL; | |
551 | ||
552 | add_wait_queue(&idev->wait, &wait); | |
553 | ||
554 | do { | |
555 | set_current_state(TASK_INTERRUPTIBLE); | |
556 | ||
557 | event_count = atomic_read(&idev->event); | |
558 | if (event_count != listener->event_count) { | |
559 | if (copy_to_user(buf, &event_count, count)) | |
560 | retval = -EFAULT; | |
561 | else { | |
562 | listener->event_count = event_count; | |
563 | retval = count; | |
564 | } | |
565 | break; | |
566 | } | |
567 | ||
568 | if (filep->f_flags & O_NONBLOCK) { | |
569 | retval = -EAGAIN; | |
570 | break; | |
571 | } | |
572 | ||
573 | if (signal_pending(current)) { | |
574 | retval = -ERESTARTSYS; | |
575 | break; | |
576 | } | |
577 | schedule(); | |
578 | } while (1); | |
579 | ||
580 | __set_current_state(TASK_RUNNING); | |
581 | remove_wait_queue(&idev->wait, &wait); | |
582 | ||
583 | return retval; | |
584 | } | |
585 | ||
328a14e7 HK |
586 | static ssize_t uio_write(struct file *filep, const char __user *buf, |
587 | size_t count, loff_t *ppos) | |
588 | { | |
589 | struct uio_listener *listener = filep->private_data; | |
590 | struct uio_device *idev = listener->dev; | |
591 | ssize_t retval; | |
592 | s32 irq_on; | |
593 | ||
594 | if (idev->info->irq == UIO_IRQ_NONE) | |
595 | return -EIO; | |
596 | ||
597 | if (count != sizeof(s32)) | |
598 | return -EINVAL; | |
599 | ||
600 | if (!idev->info->irqcontrol) | |
601 | return -ENOSYS; | |
602 | ||
603 | if (copy_from_user(&irq_on, buf, count)) | |
604 | return -EFAULT; | |
605 | ||
606 | retval = idev->info->irqcontrol(idev->info, irq_on); | |
607 | ||
608 | return retval ? retval : sizeof(s32); | |
609 | } | |
610 | ||
beafc54c HK |
611 | static int uio_find_mem_index(struct vm_area_struct *vma) |
612 | { | |
613 | int mi; | |
614 | struct uio_device *idev = vma->vm_private_data; | |
615 | ||
616 | for (mi = 0; mi < MAX_UIO_MAPS; mi++) { | |
617 | if (idev->info->mem[mi].size == 0) | |
618 | return -1; | |
619 | if (vma->vm_pgoff == mi) | |
620 | return mi; | |
621 | } | |
622 | return -1; | |
623 | } | |
624 | ||
625 | static void uio_vma_open(struct vm_area_struct *vma) | |
626 | { | |
627 | struct uio_device *idev = vma->vm_private_data; | |
628 | idev->vma_count++; | |
629 | } | |
630 | ||
631 | static void uio_vma_close(struct vm_area_struct *vma) | |
632 | { | |
633 | struct uio_device *idev = vma->vm_private_data; | |
634 | idev->vma_count--; | |
635 | } | |
636 | ||
a18b630d | 637 | static int uio_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
beafc54c HK |
638 | { |
639 | struct uio_device *idev = vma->vm_private_data; | |
a18b630d | 640 | struct page *page; |
02683ffd | 641 | unsigned long offset; |
beafc54c HK |
642 | |
643 | int mi = uio_find_mem_index(vma); | |
644 | if (mi < 0) | |
a18b630d | 645 | return VM_FAULT_SIGBUS; |
beafc54c | 646 | |
02683ffd AH |
647 | /* |
648 | * We need to subtract mi because userspace uses offset = N*PAGE_SIZE | |
649 | * to use mem[N]. | |
650 | */ | |
651 | offset = (vmf->pgoff - mi) << PAGE_SHIFT; | |
652 | ||
beafc54c | 653 | if (idev->info->mem[mi].memtype == UIO_MEM_LOGICAL) |
02683ffd | 654 | page = virt_to_page(idev->info->mem[mi].addr + offset); |
beafc54c | 655 | else |
02683ffd AH |
656 | page = vmalloc_to_page((void *)idev->info->mem[mi].addr |
657 | + offset); | |
beafc54c | 658 | get_page(page); |
a18b630d NP |
659 | vmf->page = page; |
660 | return 0; | |
beafc54c HK |
661 | } |
662 | ||
f0f37e2f | 663 | static const struct vm_operations_struct uio_vm_ops = { |
beafc54c HK |
664 | .open = uio_vma_open, |
665 | .close = uio_vma_close, | |
a18b630d | 666 | .fault = uio_vma_fault, |
beafc54c HK |
667 | }; |
668 | ||
669 | static int uio_mmap_physical(struct vm_area_struct *vma) | |
670 | { | |
671 | struct uio_device *idev = vma->vm_private_data; | |
672 | int mi = uio_find_mem_index(vma); | |
673 | if (mi < 0) | |
674 | return -EINVAL; | |
675 | ||
676 | vma->vm_flags |= VM_IO | VM_RESERVED; | |
c9698d6b JSC |
677 | |
678 | vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); | |
beafc54c HK |
679 | |
680 | return remap_pfn_range(vma, | |
681 | vma->vm_start, | |
682 | idev->info->mem[mi].addr >> PAGE_SHIFT, | |
683 | vma->vm_end - vma->vm_start, | |
684 | vma->vm_page_prot); | |
685 | } | |
686 | ||
687 | static int uio_mmap_logical(struct vm_area_struct *vma) | |
688 | { | |
689 | vma->vm_flags |= VM_RESERVED; | |
690 | vma->vm_ops = &uio_vm_ops; | |
691 | uio_vma_open(vma); | |
692 | return 0; | |
693 | } | |
694 | ||
695 | static int uio_mmap(struct file *filep, struct vm_area_struct *vma) | |
696 | { | |
697 | struct uio_listener *listener = filep->private_data; | |
698 | struct uio_device *idev = listener->dev; | |
699 | int mi; | |
700 | unsigned long requested_pages, actual_pages; | |
701 | int ret = 0; | |
702 | ||
703 | if (vma->vm_end < vma->vm_start) | |
704 | return -EINVAL; | |
705 | ||
706 | vma->vm_private_data = idev; | |
707 | ||
708 | mi = uio_find_mem_index(vma); | |
709 | if (mi < 0) | |
710 | return -EINVAL; | |
711 | ||
712 | requested_pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; | |
6da2d377 IA |
713 | actual_pages = ((idev->info->mem[mi].addr & ~PAGE_MASK) |
714 | + idev->info->mem[mi].size + PAGE_SIZE -1) >> PAGE_SHIFT; | |
beafc54c HK |
715 | if (requested_pages > actual_pages) |
716 | return -EINVAL; | |
717 | ||
718 | if (idev->info->mmap) { | |
beafc54c | 719 | ret = idev->info->mmap(idev->info, vma); |
beafc54c HK |
720 | return ret; |
721 | } | |
722 | ||
723 | switch (idev->info->mem[mi].memtype) { | |
724 | case UIO_MEM_PHYS: | |
725 | return uio_mmap_physical(vma); | |
726 | case UIO_MEM_LOGICAL: | |
727 | case UIO_MEM_VIRTUAL: | |
728 | return uio_mmap_logical(vma); | |
729 | default: | |
730 | return -EINVAL; | |
731 | } | |
732 | } | |
733 | ||
4f014691 | 734 | static const struct file_operations uio_fops = { |
beafc54c HK |
735 | .owner = THIS_MODULE, |
736 | .open = uio_open, | |
737 | .release = uio_release, | |
738 | .read = uio_read, | |
328a14e7 | 739 | .write = uio_write, |
beafc54c HK |
740 | .mmap = uio_mmap, |
741 | .poll = uio_poll, | |
742 | .fasync = uio_fasync, | |
743 | }; | |
744 | ||
745 | static int uio_major_init(void) | |
746 | { | |
747 | uio_major = register_chrdev(0, "uio", &uio_fops); | |
748 | if (uio_major < 0) | |
749 | return uio_major; | |
750 | return 0; | |
751 | } | |
752 | ||
753 | static void uio_major_cleanup(void) | |
754 | { | |
755 | unregister_chrdev(uio_major, "uio"); | |
756 | } | |
757 | ||
758 | static int init_uio_class(void) | |
759 | { | |
760 | int ret = 0; | |
761 | ||
762 | if (uio_class != NULL) { | |
763 | kref_get(&uio_class->kref); | |
764 | goto exit; | |
765 | } | |
766 | ||
767 | /* This is the first time in here, set everything up properly */ | |
768 | ret = uio_major_init(); | |
769 | if (ret) | |
770 | goto exit; | |
771 | ||
772 | uio_class = kzalloc(sizeof(*uio_class), GFP_KERNEL); | |
773 | if (!uio_class) { | |
774 | ret = -ENOMEM; | |
775 | goto err_kzalloc; | |
776 | } | |
777 | ||
778 | kref_init(&uio_class->kref); | |
779 | uio_class->class = class_create(THIS_MODULE, "uio"); | |
780 | if (IS_ERR(uio_class->class)) { | |
781 | ret = IS_ERR(uio_class->class); | |
782 | printk(KERN_ERR "class_create failed for uio\n"); | |
783 | goto err_class_create; | |
784 | } | |
785 | return 0; | |
786 | ||
787 | err_class_create: | |
788 | kfree(uio_class); | |
789 | uio_class = NULL; | |
790 | err_kzalloc: | |
791 | uio_major_cleanup(); | |
792 | exit: | |
793 | return ret; | |
794 | } | |
795 | ||
796 | static void release_uio_class(struct kref *kref) | |
797 | { | |
798 | /* Ok, we cheat as we know we only have one uio_class */ | |
799 | class_destroy(uio_class->class); | |
800 | kfree(uio_class); | |
801 | uio_major_cleanup(); | |
802 | uio_class = NULL; | |
803 | } | |
804 | ||
805 | static void uio_class_destroy(void) | |
806 | { | |
807 | if (uio_class) | |
808 | kref_put(&uio_class->kref, release_uio_class); | |
809 | } | |
810 | ||
811 | /** | |
812 | * uio_register_device - register a new userspace IO device | |
813 | * @owner: module that creates the new device | |
814 | * @parent: parent device | |
815 | * @info: UIO device capabilities | |
816 | * | |
817 | * returns zero on success or a negative error code. | |
818 | */ | |
819 | int __uio_register_device(struct module *owner, | |
820 | struct device *parent, | |
821 | struct uio_info *info) | |
822 | { | |
823 | struct uio_device *idev; | |
824 | int ret = 0; | |
825 | ||
826 | if (!parent || !info || !info->name || !info->version) | |
827 | return -EINVAL; | |
828 | ||
829 | info->uio_dev = NULL; | |
830 | ||
831 | ret = init_uio_class(); | |
832 | if (ret) | |
833 | return ret; | |
834 | ||
835 | idev = kzalloc(sizeof(*idev), GFP_KERNEL); | |
836 | if (!idev) { | |
837 | ret = -ENOMEM; | |
838 | goto err_kzalloc; | |
839 | } | |
840 | ||
841 | idev->owner = owner; | |
842 | idev->info = info; | |
843 | init_waitqueue_head(&idev->wait); | |
844 | atomic_set(&idev->event, 0); | |
845 | ||
846 | ret = uio_get_minor(idev); | |
847 | if (ret) | |
848 | goto err_get_minor; | |
849 | ||
a9b12619 GKH |
850 | idev->dev = device_create(uio_class->class, parent, |
851 | MKDEV(uio_major, idev->minor), idev, | |
852 | "uio%d", idev->minor); | |
beafc54c HK |
853 | if (IS_ERR(idev->dev)) { |
854 | printk(KERN_ERR "UIO: device register failed\n"); | |
855 | ret = PTR_ERR(idev->dev); | |
856 | goto err_device_create; | |
857 | } | |
beafc54c HK |
858 | |
859 | ret = uio_dev_add_attributes(idev); | |
860 | if (ret) | |
861 | goto err_uio_dev_add_attributes; | |
862 | ||
863 | info->uio_dev = idev; | |
864 | ||
865 | if (idev->info->irq >= 0) { | |
866 | ret = request_irq(idev->info->irq, uio_interrupt, | |
867 | idev->info->irq_flags, idev->info->name, idev); | |
868 | if (ret) | |
869 | goto err_request_irq; | |
870 | } | |
871 | ||
872 | return 0; | |
873 | ||
874 | err_request_irq: | |
875 | uio_dev_del_attributes(idev); | |
876 | err_uio_dev_add_attributes: | |
877 | device_destroy(uio_class->class, MKDEV(uio_major, idev->minor)); | |
878 | err_device_create: | |
879 | uio_free_minor(idev); | |
880 | err_get_minor: | |
881 | kfree(idev); | |
882 | err_kzalloc: | |
883 | uio_class_destroy(); | |
884 | return ret; | |
885 | } | |
886 | EXPORT_SYMBOL_GPL(__uio_register_device); | |
887 | ||
888 | /** | |
889 | * uio_unregister_device - unregister a industrial IO device | |
890 | * @info: UIO device capabilities | |
891 | * | |
892 | */ | |
893 | void uio_unregister_device(struct uio_info *info) | |
894 | { | |
895 | struct uio_device *idev; | |
896 | ||
897 | if (!info || !info->uio_dev) | |
898 | return; | |
899 | ||
900 | idev = info->uio_dev; | |
901 | ||
902 | uio_free_minor(idev); | |
903 | ||
904 | if (info->irq >= 0) | |
905 | free_irq(info->irq, idev); | |
906 | ||
907 | uio_dev_del_attributes(idev); | |
908 | ||
909 | dev_set_drvdata(idev->dev, NULL); | |
910 | device_destroy(uio_class->class, MKDEV(uio_major, idev->minor)); | |
911 | kfree(idev); | |
912 | uio_class_destroy(); | |
913 | ||
914 | return; | |
915 | } | |
916 | EXPORT_SYMBOL_GPL(uio_unregister_device); | |
917 | ||
918 | static int __init uio_init(void) | |
919 | { | |
920 | return 0; | |
921 | } | |
922 | ||
923 | static void __exit uio_exit(void) | |
924 | { | |
925 | } | |
926 | ||
927 | module_init(uio_init) | |
928 | module_exit(uio_exit) | |
929 | MODULE_LICENSE("GPL v2"); |