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