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 */ | |
3d4f9d76 | 48 | static struct class *uio_class; |
beafc54c | 49 | |
0d4a7bc1 JC |
50 | /* Protect idr accesses */ |
51 | static DEFINE_MUTEX(minor_lock); | |
52 | ||
beafc54c HK |
53 | /* |
54 | * attributes | |
55 | */ | |
56 | ||
81e7c6a6 GKH |
57 | struct uio_map { |
58 | struct kobject kobj; | |
59 | struct uio_mem *mem; | |
beafc54c | 60 | }; |
81e7c6a6 | 61 | #define to_map(map) container_of(map, struct uio_map, kobj) |
beafc54c | 62 | |
82057791 HK |
63 | static ssize_t map_name_show(struct uio_mem *mem, char *buf) |
64 | { | |
65 | if (unlikely(!mem->name)) | |
66 | mem->name = ""; | |
67 | ||
68 | return sprintf(buf, "%s\n", mem->name); | |
69 | } | |
70 | ||
4f808bcd | 71 | static ssize_t map_addr_show(struct uio_mem *mem, char *buf) |
beafc54c | 72 | { |
4f808bcd BP |
73 | return sprintf(buf, "0x%lx\n", mem->addr); |
74 | } | |
beafc54c | 75 | |
4f808bcd BP |
76 | static ssize_t map_size_show(struct uio_mem *mem, char *buf) |
77 | { | |
78 | return sprintf(buf, "0x%lx\n", mem->size); | |
beafc54c HK |
79 | } |
80 | ||
e2b39df1 HK |
81 | static ssize_t map_offset_show(struct uio_mem *mem, char *buf) |
82 | { | |
83 | return sprintf(buf, "0x%lx\n", mem->addr & ~PAGE_MASK); | |
84 | } | |
85 | ||
e70c412e | 86 | struct map_sysfs_entry { |
4f808bcd BP |
87 | struct attribute attr; |
88 | ssize_t (*show)(struct uio_mem *, char *); | |
89 | ssize_t (*store)(struct uio_mem *, const char *, size_t); | |
90 | }; | |
91 | ||
82057791 HK |
92 | static struct map_sysfs_entry name_attribute = |
93 | __ATTR(name, S_IRUGO, map_name_show, NULL); | |
e70c412e | 94 | static struct map_sysfs_entry addr_attribute = |
4f808bcd | 95 | __ATTR(addr, S_IRUGO, map_addr_show, NULL); |
e70c412e | 96 | static struct map_sysfs_entry size_attribute = |
4f808bcd | 97 | __ATTR(size, S_IRUGO, map_size_show, NULL); |
e70c412e | 98 | static struct map_sysfs_entry offset_attribute = |
e2b39df1 | 99 | __ATTR(offset, S_IRUGO, map_offset_show, NULL); |
beafc54c | 100 | |
81e7c6a6 | 101 | static struct attribute *attrs[] = { |
82057791 | 102 | &name_attribute.attr, |
4f808bcd | 103 | &addr_attribute.attr, |
81e7c6a6 | 104 | &size_attribute.attr, |
e2b39df1 | 105 | &offset_attribute.attr, |
81e7c6a6 | 106 | NULL, /* need to NULL terminate the list of attributes */ |
beafc54c HK |
107 | }; |
108 | ||
81e7c6a6 GKH |
109 | static void map_release(struct kobject *kobj) |
110 | { | |
111 | struct uio_map *map = to_map(kobj); | |
112 | kfree(map); | |
113 | } | |
114 | ||
4f808bcd BP |
115 | static ssize_t map_type_show(struct kobject *kobj, struct attribute *attr, |
116 | char *buf) | |
117 | { | |
118 | struct uio_map *map = to_map(kobj); | |
119 | struct uio_mem *mem = map->mem; | |
e70c412e | 120 | struct map_sysfs_entry *entry; |
4f808bcd | 121 | |
e70c412e | 122 | entry = container_of(attr, struct map_sysfs_entry, attr); |
4f808bcd BP |
123 | |
124 | if (!entry->show) | |
125 | return -EIO; | |
126 | ||
127 | return entry->show(mem, buf); | |
128 | } | |
129 | ||
52cf25d0 | 130 | static const struct sysfs_ops map_sysfs_ops = { |
4f808bcd BP |
131 | .show = map_type_show, |
132 | }; | |
133 | ||
beafc54c | 134 | static struct kobj_type map_attr_type = { |
81e7c6a6 | 135 | .release = map_release, |
e70c412e | 136 | .sysfs_ops = &map_sysfs_ops, |
81e7c6a6 | 137 | .default_attrs = attrs, |
beafc54c HK |
138 | }; |
139 | ||
e70c412e HK |
140 | struct uio_portio { |
141 | struct kobject kobj; | |
142 | struct uio_port *port; | |
143 | }; | |
144 | #define to_portio(portio) container_of(portio, struct uio_portio, kobj) | |
145 | ||
82057791 HK |
146 | static ssize_t portio_name_show(struct uio_port *port, char *buf) |
147 | { | |
148 | if (unlikely(!port->name)) | |
149 | port->name = ""; | |
150 | ||
151 | return sprintf(buf, "%s\n", port->name); | |
152 | } | |
153 | ||
e70c412e HK |
154 | static ssize_t portio_start_show(struct uio_port *port, char *buf) |
155 | { | |
156 | return sprintf(buf, "0x%lx\n", port->start); | |
157 | } | |
158 | ||
159 | static ssize_t portio_size_show(struct uio_port *port, char *buf) | |
160 | { | |
161 | return sprintf(buf, "0x%lx\n", port->size); | |
162 | } | |
163 | ||
164 | static ssize_t portio_porttype_show(struct uio_port *port, char *buf) | |
165 | { | |
166 | const char *porttypes[] = {"none", "x86", "gpio", "other"}; | |
167 | ||
168 | if ((port->porttype < 0) || (port->porttype > UIO_PORT_OTHER)) | |
169 | return -EINVAL; | |
170 | ||
171 | return sprintf(buf, "port_%s\n", porttypes[port->porttype]); | |
172 | } | |
173 | ||
174 | struct portio_sysfs_entry { | |
175 | struct attribute attr; | |
176 | ssize_t (*show)(struct uio_port *, char *); | |
177 | ssize_t (*store)(struct uio_port *, const char *, size_t); | |
178 | }; | |
179 | ||
82057791 HK |
180 | static struct portio_sysfs_entry portio_name_attribute = |
181 | __ATTR(name, S_IRUGO, portio_name_show, NULL); | |
e70c412e HK |
182 | static struct portio_sysfs_entry portio_start_attribute = |
183 | __ATTR(start, S_IRUGO, portio_start_show, NULL); | |
184 | static struct portio_sysfs_entry portio_size_attribute = | |
185 | __ATTR(size, S_IRUGO, portio_size_show, NULL); | |
186 | static struct portio_sysfs_entry portio_porttype_attribute = | |
187 | __ATTR(porttype, S_IRUGO, portio_porttype_show, NULL); | |
188 | ||
189 | static struct attribute *portio_attrs[] = { | |
82057791 | 190 | &portio_name_attribute.attr, |
e70c412e HK |
191 | &portio_start_attribute.attr, |
192 | &portio_size_attribute.attr, | |
193 | &portio_porttype_attribute.attr, | |
194 | NULL, | |
195 | }; | |
196 | ||
197 | static void portio_release(struct kobject *kobj) | |
198 | { | |
199 | struct uio_portio *portio = to_portio(kobj); | |
200 | kfree(portio); | |
201 | } | |
202 | ||
203 | static ssize_t portio_type_show(struct kobject *kobj, struct attribute *attr, | |
204 | char *buf) | |
205 | { | |
206 | struct uio_portio *portio = to_portio(kobj); | |
207 | struct uio_port *port = portio->port; | |
208 | struct portio_sysfs_entry *entry; | |
209 | ||
210 | entry = container_of(attr, struct portio_sysfs_entry, attr); | |
211 | ||
212 | if (!entry->show) | |
213 | return -EIO; | |
214 | ||
215 | return entry->show(port, buf); | |
216 | } | |
217 | ||
52cf25d0 | 218 | static const struct sysfs_ops portio_sysfs_ops = { |
e70c412e HK |
219 | .show = portio_type_show, |
220 | }; | |
221 | ||
222 | static struct kobj_type portio_attr_type = { | |
223 | .release = portio_release, | |
224 | .sysfs_ops = &portio_sysfs_ops, | |
225 | .default_attrs = portio_attrs, | |
226 | }; | |
227 | ||
beafc54c HK |
228 | static ssize_t show_name(struct device *dev, |
229 | struct device_attribute *attr, char *buf) | |
230 | { | |
231 | struct uio_device *idev = dev_get_drvdata(dev); | |
232 | if (idev) | |
233 | return sprintf(buf, "%s\n", idev->info->name); | |
234 | else | |
235 | return -ENODEV; | |
236 | } | |
237 | static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); | |
238 | ||
239 | static ssize_t show_version(struct device *dev, | |
240 | struct device_attribute *attr, char *buf) | |
241 | { | |
242 | struct uio_device *idev = dev_get_drvdata(dev); | |
243 | if (idev) | |
244 | return sprintf(buf, "%s\n", idev->info->version); | |
245 | else | |
246 | return -ENODEV; | |
247 | } | |
248 | static DEVICE_ATTR(version, S_IRUGO, show_version, NULL); | |
249 | ||
250 | static ssize_t show_event(struct device *dev, | |
251 | struct device_attribute *attr, char *buf) | |
252 | { | |
253 | struct uio_device *idev = dev_get_drvdata(dev); | |
254 | if (idev) | |
255 | return sprintf(buf, "%u\n", | |
256 | (unsigned int)atomic_read(&idev->event)); | |
257 | else | |
258 | return -ENODEV; | |
259 | } | |
260 | static DEVICE_ATTR(event, S_IRUGO, show_event, NULL); | |
261 | ||
262 | static struct attribute *uio_attrs[] = { | |
263 | &dev_attr_name.attr, | |
264 | &dev_attr_version.attr, | |
265 | &dev_attr_event.attr, | |
266 | NULL, | |
267 | }; | |
268 | ||
269 | static struct attribute_group uio_attr_grp = { | |
270 | .attrs = uio_attrs, | |
271 | }; | |
272 | ||
273 | /* | |
274 | * device functions | |
275 | */ | |
276 | static int uio_dev_add_attributes(struct uio_device *idev) | |
277 | { | |
278 | int ret; | |
e70c412e | 279 | int mi, pi; |
beafc54c | 280 | int map_found = 0; |
e70c412e | 281 | int portio_found = 0; |
beafc54c | 282 | struct uio_mem *mem; |
81e7c6a6 | 283 | struct uio_map *map; |
e70c412e HK |
284 | struct uio_port *port; |
285 | struct uio_portio *portio; | |
beafc54c HK |
286 | |
287 | ret = sysfs_create_group(&idev->dev->kobj, &uio_attr_grp); | |
288 | if (ret) | |
289 | goto err_group; | |
290 | ||
291 | for (mi = 0; mi < MAX_UIO_MAPS; mi++) { | |
292 | mem = &idev->info->mem[mi]; | |
293 | if (mem->size == 0) | |
294 | break; | |
295 | if (!map_found) { | |
296 | map_found = 1; | |
81e7c6a6 GKH |
297 | idev->map_dir = kobject_create_and_add("maps", |
298 | &idev->dev->kobj); | |
299 | if (!idev->map_dir) | |
e70c412e | 300 | goto err_map; |
beafc54c | 301 | } |
81e7c6a6 GKH |
302 | map = kzalloc(sizeof(*map), GFP_KERNEL); |
303 | if (!map) | |
e70c412e | 304 | goto err_map; |
f9cb074b | 305 | kobject_init(&map->kobj, &map_attr_type); |
81e7c6a6 GKH |
306 | map->mem = mem; |
307 | mem->map = map; | |
b2d6db58 | 308 | ret = kobject_add(&map->kobj, idev->map_dir, "map%d", mi); |
81e7c6a6 | 309 | if (ret) |
e70c412e | 310 | goto err_map; |
81e7c6a6 | 311 | ret = kobject_uevent(&map->kobj, KOBJ_ADD); |
beafc54c | 312 | if (ret) |
e70c412e HK |
313 | goto err_map; |
314 | } | |
315 | ||
316 | for (pi = 0; pi < MAX_UIO_PORT_REGIONS; pi++) { | |
317 | port = &idev->info->port[pi]; | |
318 | if (port->size == 0) | |
319 | break; | |
320 | if (!portio_found) { | |
321 | portio_found = 1; | |
322 | idev->portio_dir = kobject_create_and_add("portio", | |
323 | &idev->dev->kobj); | |
324 | if (!idev->portio_dir) | |
325 | goto err_portio; | |
326 | } | |
327 | portio = kzalloc(sizeof(*portio), GFP_KERNEL); | |
328 | if (!portio) | |
329 | goto err_portio; | |
330 | kobject_init(&portio->kobj, &portio_attr_type); | |
331 | portio->port = port; | |
332 | port->portio = portio; | |
333 | ret = kobject_add(&portio->kobj, idev->portio_dir, | |
334 | "port%d", pi); | |
335 | if (ret) | |
336 | goto err_portio; | |
337 | ret = kobject_uevent(&portio->kobj, KOBJ_ADD); | |
338 | if (ret) | |
339 | goto err_portio; | |
beafc54c HK |
340 | } |
341 | ||
342 | return 0; | |
343 | ||
e70c412e HK |
344 | err_portio: |
345 | for (pi--; pi >= 0; pi--) { | |
346 | port = &idev->info->port[pi]; | |
347 | portio = port->portio; | |
348 | kobject_put(&portio->kobj); | |
349 | } | |
350 | kobject_put(idev->portio_dir); | |
351 | err_map: | |
beafc54c HK |
352 | for (mi--; mi>=0; mi--) { |
353 | mem = &idev->info->mem[mi]; | |
81e7c6a6 | 354 | map = mem->map; |
c10997f6 | 355 | kobject_put(&map->kobj); |
beafc54c | 356 | } |
c10997f6 | 357 | kobject_put(idev->map_dir); |
beafc54c HK |
358 | sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp); |
359 | err_group: | |
360 | dev_err(idev->dev, "error creating sysfs files (%d)\n", ret); | |
361 | return ret; | |
362 | } | |
363 | ||
364 | static void uio_dev_del_attributes(struct uio_device *idev) | |
365 | { | |
e70c412e | 366 | int i; |
beafc54c | 367 | struct uio_mem *mem; |
e70c412e HK |
368 | struct uio_port *port; |
369 | ||
370 | for (i = 0; i < MAX_UIO_MAPS; i++) { | |
371 | mem = &idev->info->mem[i]; | |
beafc54c HK |
372 | if (mem->size == 0) |
373 | break; | |
c10997f6 | 374 | kobject_put(&mem->map->kobj); |
beafc54c | 375 | } |
c10997f6 | 376 | kobject_put(idev->map_dir); |
e70c412e HK |
377 | |
378 | for (i = 0; i < MAX_UIO_PORT_REGIONS; i++) { | |
379 | port = &idev->info->port[i]; | |
380 | if (port->size == 0) | |
381 | break; | |
382 | kobject_put(&port->portio->kobj); | |
383 | } | |
384 | kobject_put(idev->portio_dir); | |
385 | ||
beafc54c HK |
386 | sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp); |
387 | } | |
388 | ||
389 | static int uio_get_minor(struct uio_device *idev) | |
390 | { | |
beafc54c HK |
391 | int retval = -ENOMEM; |
392 | int id; | |
393 | ||
394 | mutex_lock(&minor_lock); | |
395 | if (idr_pre_get(&uio_idr, GFP_KERNEL) == 0) | |
396 | goto exit; | |
397 | ||
398 | retval = idr_get_new(&uio_idr, idev, &id); | |
399 | if (retval < 0) { | |
400 | if (retval == -EAGAIN) | |
401 | retval = -ENOMEM; | |
402 | goto exit; | |
403 | } | |
404 | idev->minor = id & MAX_ID_MASK; | |
405 | exit: | |
406 | mutex_unlock(&minor_lock); | |
407 | return retval; | |
408 | } | |
409 | ||
410 | static void uio_free_minor(struct uio_device *idev) | |
411 | { | |
0d4a7bc1 | 412 | mutex_lock(&minor_lock); |
beafc54c | 413 | idr_remove(&uio_idr, idev->minor); |
0d4a7bc1 | 414 | mutex_unlock(&minor_lock); |
beafc54c HK |
415 | } |
416 | ||
417 | /** | |
418 | * uio_event_notify - trigger an interrupt event | |
419 | * @info: UIO device capabilities | |
420 | */ | |
421 | void uio_event_notify(struct uio_info *info) | |
422 | { | |
423 | struct uio_device *idev = info->uio_dev; | |
424 | ||
425 | atomic_inc(&idev->event); | |
426 | wake_up_interruptible(&idev->wait); | |
427 | kill_fasync(&idev->async_queue, SIGIO, POLL_IN); | |
428 | } | |
429 | EXPORT_SYMBOL_GPL(uio_event_notify); | |
430 | ||
431 | /** | |
432 | * uio_interrupt - hardware interrupt handler | |
433 | * @irq: IRQ number, can be UIO_IRQ_CYCLIC for cyclic timer | |
434 | * @dev_id: Pointer to the devices uio_device structure | |
435 | */ | |
436 | static irqreturn_t uio_interrupt(int irq, void *dev_id) | |
437 | { | |
438 | struct uio_device *idev = (struct uio_device *)dev_id; | |
439 | irqreturn_t ret = idev->info->handler(irq, idev->info); | |
440 | ||
441 | if (ret == IRQ_HANDLED) | |
442 | uio_event_notify(idev->info); | |
443 | ||
444 | return ret; | |
445 | } | |
446 | ||
447 | struct uio_listener { | |
448 | struct uio_device *dev; | |
449 | s32 event_count; | |
450 | }; | |
451 | ||
452 | static int uio_open(struct inode *inode, struct file *filep) | |
453 | { | |
454 | struct uio_device *idev; | |
455 | struct uio_listener *listener; | |
456 | int ret = 0; | |
457 | ||
0d4a7bc1 | 458 | mutex_lock(&minor_lock); |
beafc54c | 459 | idev = idr_find(&uio_idr, iminor(inode)); |
0d4a7bc1 | 460 | mutex_unlock(&minor_lock); |
fbc8a81d JC |
461 | if (!idev) { |
462 | ret = -ENODEV; | |
463 | goto out; | |
464 | } | |
beafc54c | 465 | |
fbc8a81d JC |
466 | if (!try_module_get(idev->owner)) { |
467 | ret = -ENODEV; | |
468 | goto out; | |
469 | } | |
610ad506 | 470 | |
beafc54c | 471 | listener = kmalloc(sizeof(*listener), GFP_KERNEL); |
610ad506 UKK |
472 | if (!listener) { |
473 | ret = -ENOMEM; | |
474 | goto err_alloc_listener; | |
475 | } | |
beafc54c HK |
476 | |
477 | listener->dev = idev; | |
478 | listener->event_count = atomic_read(&idev->event); | |
479 | filep->private_data = listener; | |
480 | ||
481 | if (idev->info->open) { | |
beafc54c | 482 | ret = idev->info->open(idev->info, inode); |
610ad506 UKK |
483 | if (ret) |
484 | goto err_infoopen; | |
beafc54c | 485 | } |
610ad506 UKK |
486 | return 0; |
487 | ||
488 | err_infoopen: | |
610ad506 | 489 | kfree(listener); |
610ad506 | 490 | |
0d4a7bc1 | 491 | err_alloc_listener: |
610ad506 | 492 | module_put(idev->owner); |
beafc54c | 493 | |
fbc8a81d | 494 | out: |
beafc54c HK |
495 | return ret; |
496 | } | |
497 | ||
498 | static int uio_fasync(int fd, struct file *filep, int on) | |
499 | { | |
500 | struct uio_listener *listener = filep->private_data; | |
501 | struct uio_device *idev = listener->dev; | |
502 | ||
503 | return fasync_helper(fd, filep, on, &idev->async_queue); | |
504 | } | |
505 | ||
506 | static int uio_release(struct inode *inode, struct file *filep) | |
507 | { | |
508 | int ret = 0; | |
509 | struct uio_listener *listener = filep->private_data; | |
510 | struct uio_device *idev = listener->dev; | |
511 | ||
610ad506 | 512 | if (idev->info->release) |
beafc54c | 513 | ret = idev->info->release(idev->info, inode); |
610ad506 UKK |
514 | |
515 | module_put(idev->owner); | |
beafc54c HK |
516 | kfree(listener); |
517 | return ret; | |
518 | } | |
519 | ||
520 | static unsigned int uio_poll(struct file *filep, poll_table *wait) | |
521 | { | |
522 | struct uio_listener *listener = filep->private_data; | |
523 | struct uio_device *idev = listener->dev; | |
524 | ||
525 | if (idev->info->irq == UIO_IRQ_NONE) | |
526 | return -EIO; | |
527 | ||
528 | poll_wait(filep, &idev->wait, wait); | |
529 | if (listener->event_count != atomic_read(&idev->event)) | |
530 | return POLLIN | POLLRDNORM; | |
531 | return 0; | |
532 | } | |
533 | ||
534 | static ssize_t uio_read(struct file *filep, char __user *buf, | |
535 | size_t count, loff_t *ppos) | |
536 | { | |
537 | struct uio_listener *listener = filep->private_data; | |
538 | struct uio_device *idev = listener->dev; | |
539 | DECLARE_WAITQUEUE(wait, current); | |
540 | ssize_t retval; | |
541 | s32 event_count; | |
542 | ||
543 | if (idev->info->irq == UIO_IRQ_NONE) | |
544 | return -EIO; | |
545 | ||
546 | if (count != sizeof(s32)) | |
547 | return -EINVAL; | |
548 | ||
549 | add_wait_queue(&idev->wait, &wait); | |
550 | ||
551 | do { | |
552 | set_current_state(TASK_INTERRUPTIBLE); | |
553 | ||
554 | event_count = atomic_read(&idev->event); | |
555 | if (event_count != listener->event_count) { | |
556 | if (copy_to_user(buf, &event_count, count)) | |
557 | retval = -EFAULT; | |
558 | else { | |
559 | listener->event_count = event_count; | |
560 | retval = count; | |
561 | } | |
562 | break; | |
563 | } | |
564 | ||
565 | if (filep->f_flags & O_NONBLOCK) { | |
566 | retval = -EAGAIN; | |
567 | break; | |
568 | } | |
569 | ||
570 | if (signal_pending(current)) { | |
571 | retval = -ERESTARTSYS; | |
572 | break; | |
573 | } | |
574 | schedule(); | |
575 | } while (1); | |
576 | ||
577 | __set_current_state(TASK_RUNNING); | |
578 | remove_wait_queue(&idev->wait, &wait); | |
579 | ||
580 | return retval; | |
581 | } | |
582 | ||
328a14e7 HK |
583 | static ssize_t uio_write(struct file *filep, const char __user *buf, |
584 | size_t count, loff_t *ppos) | |
585 | { | |
586 | struct uio_listener *listener = filep->private_data; | |
587 | struct uio_device *idev = listener->dev; | |
588 | ssize_t retval; | |
589 | s32 irq_on; | |
590 | ||
591 | if (idev->info->irq == UIO_IRQ_NONE) | |
592 | return -EIO; | |
593 | ||
594 | if (count != sizeof(s32)) | |
595 | return -EINVAL; | |
596 | ||
597 | if (!idev->info->irqcontrol) | |
598 | return -ENOSYS; | |
599 | ||
600 | if (copy_from_user(&irq_on, buf, count)) | |
601 | return -EFAULT; | |
602 | ||
603 | retval = idev->info->irqcontrol(idev->info, irq_on); | |
604 | ||
605 | return retval ? retval : sizeof(s32); | |
606 | } | |
607 | ||
beafc54c HK |
608 | static int uio_find_mem_index(struct vm_area_struct *vma) |
609 | { | |
610 | int mi; | |
611 | struct uio_device *idev = vma->vm_private_data; | |
612 | ||
613 | for (mi = 0; mi < MAX_UIO_MAPS; mi++) { | |
614 | if (idev->info->mem[mi].size == 0) | |
615 | return -1; | |
616 | if (vma->vm_pgoff == mi) | |
617 | return mi; | |
618 | } | |
619 | return -1; | |
620 | } | |
621 | ||
622 | static void uio_vma_open(struct vm_area_struct *vma) | |
623 | { | |
624 | struct uio_device *idev = vma->vm_private_data; | |
625 | idev->vma_count++; | |
626 | } | |
627 | ||
628 | static void uio_vma_close(struct vm_area_struct *vma) | |
629 | { | |
630 | struct uio_device *idev = vma->vm_private_data; | |
631 | idev->vma_count--; | |
632 | } | |
633 | ||
a18b630d | 634 | static int uio_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
beafc54c HK |
635 | { |
636 | struct uio_device *idev = vma->vm_private_data; | |
a18b630d | 637 | struct page *page; |
02683ffd | 638 | unsigned long offset; |
beafc54c HK |
639 | |
640 | int mi = uio_find_mem_index(vma); | |
641 | if (mi < 0) | |
a18b630d | 642 | return VM_FAULT_SIGBUS; |
beafc54c | 643 | |
02683ffd AH |
644 | /* |
645 | * We need to subtract mi because userspace uses offset = N*PAGE_SIZE | |
646 | * to use mem[N]. | |
647 | */ | |
648 | offset = (vmf->pgoff - mi) << PAGE_SHIFT; | |
649 | ||
beafc54c | 650 | if (idev->info->mem[mi].memtype == UIO_MEM_LOGICAL) |
02683ffd | 651 | page = virt_to_page(idev->info->mem[mi].addr + offset); |
beafc54c | 652 | else |
02683ffd AH |
653 | page = vmalloc_to_page((void *)idev->info->mem[mi].addr |
654 | + offset); | |
beafc54c | 655 | get_page(page); |
a18b630d NP |
656 | vmf->page = page; |
657 | return 0; | |
beafc54c HK |
658 | } |
659 | ||
f0f37e2f | 660 | static const struct vm_operations_struct uio_vm_ops = { |
beafc54c HK |
661 | .open = uio_vma_open, |
662 | .close = uio_vma_close, | |
a18b630d | 663 | .fault = uio_vma_fault, |
beafc54c HK |
664 | }; |
665 | ||
666 | static int uio_mmap_physical(struct vm_area_struct *vma) | |
667 | { | |
668 | struct uio_device *idev = vma->vm_private_data; | |
669 | int mi = uio_find_mem_index(vma); | |
670 | if (mi < 0) | |
671 | return -EINVAL; | |
672 | ||
673 | vma->vm_flags |= VM_IO | VM_RESERVED; | |
c9698d6b JSC |
674 | |
675 | vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); | |
beafc54c HK |
676 | |
677 | return remap_pfn_range(vma, | |
678 | vma->vm_start, | |
679 | idev->info->mem[mi].addr >> PAGE_SHIFT, | |
680 | vma->vm_end - vma->vm_start, | |
681 | vma->vm_page_prot); | |
682 | } | |
683 | ||
684 | static int uio_mmap_logical(struct vm_area_struct *vma) | |
685 | { | |
686 | vma->vm_flags |= VM_RESERVED; | |
687 | vma->vm_ops = &uio_vm_ops; | |
688 | uio_vma_open(vma); | |
689 | return 0; | |
690 | } | |
691 | ||
692 | static int uio_mmap(struct file *filep, struct vm_area_struct *vma) | |
693 | { | |
694 | struct uio_listener *listener = filep->private_data; | |
695 | struct uio_device *idev = listener->dev; | |
696 | int mi; | |
697 | unsigned long requested_pages, actual_pages; | |
698 | int ret = 0; | |
699 | ||
700 | if (vma->vm_end < vma->vm_start) | |
701 | return -EINVAL; | |
702 | ||
703 | vma->vm_private_data = idev; | |
704 | ||
705 | mi = uio_find_mem_index(vma); | |
706 | if (mi < 0) | |
707 | return -EINVAL; | |
708 | ||
709 | requested_pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; | |
6da2d377 IA |
710 | actual_pages = ((idev->info->mem[mi].addr & ~PAGE_MASK) |
711 | + idev->info->mem[mi].size + PAGE_SIZE -1) >> PAGE_SHIFT; | |
beafc54c HK |
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 | { | |
3d4f9d76 EB |
757 | struct class *class; |
758 | int ret; | |
beafc54c HK |
759 | |
760 | /* This is the first time in here, set everything up properly */ | |
761 | ret = uio_major_init(); | |
762 | if (ret) | |
763 | goto exit; | |
764 | ||
3d4f9d76 EB |
765 | class = class_create(THIS_MODULE, "uio"); |
766 | if (IS_ERR(class)) { | |
767 | ret = IS_ERR(class); | |
beafc54c HK |
768 | printk(KERN_ERR "class_create failed for uio\n"); |
769 | goto err_class_create; | |
770 | } | |
3d4f9d76 | 771 | uio_class = class; |
beafc54c HK |
772 | return 0; |
773 | ||
774 | err_class_create: | |
beafc54c HK |
775 | uio_major_cleanup(); |
776 | exit: | |
777 | return ret; | |
778 | } | |
779 | ||
3d4f9d76 | 780 | static void release_uio_class(void) |
beafc54c HK |
781 | { |
782 | /* Ok, we cheat as we know we only have one uio_class */ | |
3d4f9d76 | 783 | class_destroy(uio_class); |
beafc54c | 784 | uio_class = NULL; |
3d4f9d76 | 785 | uio_major_cleanup(); |
beafc54c HK |
786 | } |
787 | ||
788 | /** | |
789 | * uio_register_device - register a new userspace IO device | |
790 | * @owner: module that creates the new device | |
791 | * @parent: parent device | |
792 | * @info: UIO device capabilities | |
793 | * | |
794 | * returns zero on success or a negative error code. | |
795 | */ | |
796 | int __uio_register_device(struct module *owner, | |
797 | struct device *parent, | |
798 | struct uio_info *info) | |
799 | { | |
800 | struct uio_device *idev; | |
801 | int ret = 0; | |
802 | ||
803 | if (!parent || !info || !info->name || !info->version) | |
804 | return -EINVAL; | |
805 | ||
806 | info->uio_dev = NULL; | |
807 | ||
beafc54c HK |
808 | idev = kzalloc(sizeof(*idev), GFP_KERNEL); |
809 | if (!idev) { | |
810 | ret = -ENOMEM; | |
811 | goto err_kzalloc; | |
812 | } | |
813 | ||
814 | idev->owner = owner; | |
815 | idev->info = info; | |
816 | init_waitqueue_head(&idev->wait); | |
817 | atomic_set(&idev->event, 0); | |
818 | ||
819 | ret = uio_get_minor(idev); | |
820 | if (ret) | |
821 | goto err_get_minor; | |
822 | ||
3d4f9d76 | 823 | idev->dev = device_create(uio_class, parent, |
a9b12619 GKH |
824 | MKDEV(uio_major, idev->minor), idev, |
825 | "uio%d", idev->minor); | |
beafc54c HK |
826 | if (IS_ERR(idev->dev)) { |
827 | printk(KERN_ERR "UIO: device register failed\n"); | |
828 | ret = PTR_ERR(idev->dev); | |
829 | goto err_device_create; | |
830 | } | |
beafc54c HK |
831 | |
832 | ret = uio_dev_add_attributes(idev); | |
833 | if (ret) | |
834 | goto err_uio_dev_add_attributes; | |
835 | ||
836 | info->uio_dev = idev; | |
837 | ||
838 | if (idev->info->irq >= 0) { | |
839 | ret = request_irq(idev->info->irq, uio_interrupt, | |
840 | idev->info->irq_flags, idev->info->name, idev); | |
841 | if (ret) | |
842 | goto err_request_irq; | |
843 | } | |
844 | ||
845 | return 0; | |
846 | ||
847 | err_request_irq: | |
848 | uio_dev_del_attributes(idev); | |
849 | err_uio_dev_add_attributes: | |
3d4f9d76 | 850 | device_destroy(uio_class, MKDEV(uio_major, idev->minor)); |
beafc54c HK |
851 | err_device_create: |
852 | uio_free_minor(idev); | |
853 | err_get_minor: | |
854 | kfree(idev); | |
855 | err_kzalloc: | |
beafc54c HK |
856 | return ret; |
857 | } | |
858 | EXPORT_SYMBOL_GPL(__uio_register_device); | |
859 | ||
860 | /** | |
861 | * uio_unregister_device - unregister a industrial IO device | |
862 | * @info: UIO device capabilities | |
863 | * | |
864 | */ | |
865 | void uio_unregister_device(struct uio_info *info) | |
866 | { | |
867 | struct uio_device *idev; | |
868 | ||
869 | if (!info || !info->uio_dev) | |
870 | return; | |
871 | ||
872 | idev = info->uio_dev; | |
873 | ||
874 | uio_free_minor(idev); | |
875 | ||
876 | if (info->irq >= 0) | |
877 | free_irq(info->irq, idev); | |
878 | ||
879 | uio_dev_del_attributes(idev); | |
880 | ||
881 | dev_set_drvdata(idev->dev, NULL); | |
3d4f9d76 | 882 | device_destroy(uio_class, MKDEV(uio_major, idev->minor)); |
beafc54c | 883 | kfree(idev); |
beafc54c HK |
884 | |
885 | return; | |
886 | } | |
887 | EXPORT_SYMBOL_GPL(uio_unregister_device); | |
888 | ||
889 | static int __init uio_init(void) | |
890 | { | |
3d4f9d76 | 891 | return init_uio_class(); |
beafc54c HK |
892 | } |
893 | ||
894 | static void __exit uio_exit(void) | |
895 | { | |
3d4f9d76 | 896 | release_uio_class(); |
beafc54c HK |
897 | } |
898 | ||
899 | module_init(uio_init) | |
900 | module_exit(uio_exit) | |
901 | MODULE_LICENSE("GPL v2"); |