blob: 03efb065455fa6ef1e9db0d091db9bcad1960e12 [file] [log] [blame]
Hans J. Kochbeafc542006-12-07 10:58:29 +01001/*
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
28struct 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;
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +000037 struct kobject *map_dir;
Hans J. Koche70c4122008-12-06 02:23:13 +010038 struct kobject *portio_dir;
Hans J. Kochbeafc542006-12-07 10:58:29 +010039};
40
41static int uio_major;
42static DEFINE_IDR(uio_idr);
Jan Engelhardt4f014692008-01-22 20:50:54 +010043static const struct file_operations uio_fops;
Hans J. Kochbeafc542006-12-07 10:58:29 +010044
45/* UIO class infrastructure */
46static struct uio_class {
47 struct kref kref;
48 struct class *class;
49} *uio_class;
50
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -060051/* Protect idr accesses */
52static DEFINE_MUTEX(minor_lock);
53
Hans J. Kochbeafc542006-12-07 10:58:29 +010054/*
55 * attributes
56 */
57
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +000058struct uio_map {
59 struct kobject kobj;
60 struct uio_mem *mem;
Hans J. Kochbeafc542006-12-07 10:58:29 +010061};
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +000062#define to_map(map) container_of(map, struct uio_map, kobj)
Hans J. Kochbeafc542006-12-07 10:58:29 +010063
Hans J. Koch82057792009-01-07 00:15:39 +010064static 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
Brandon Philips4f808bc2008-02-19 01:55:05 -080072static ssize_t map_addr_show(struct uio_mem *mem, char *buf)
Hans J. Kochbeafc542006-12-07 10:58:29 +010073{
Brandon Philips4f808bc2008-02-19 01:55:05 -080074 return sprintf(buf, "0x%lx\n", mem->addr);
Hans J. Kochbeafc542006-12-07 10:58:29 +010075}
76
Brandon Philips4f808bc2008-02-19 01:55:05 -080077static ssize_t map_size_show(struct uio_mem *mem, char *buf)
78{
79 return sprintf(buf, "0x%lx\n", mem->size);
80}
81
Hans J. Koche2b39df2008-09-18 23:53:18 +020082static 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
Hans J. Koche70c4122008-12-06 02:23:13 +010087struct map_sysfs_entry {
Brandon Philips4f808bc2008-02-19 01:55:05 -080088 struct attribute attr;
89 ssize_t (*show)(struct uio_mem *, char *);
90 ssize_t (*store)(struct uio_mem *, const char *, size_t);
91};
92
Hans J. Koch82057792009-01-07 00:15:39 +010093static struct map_sysfs_entry name_attribute =
94 __ATTR(name, S_IRUGO, map_name_show, NULL);
Hans J. Koche70c4122008-12-06 02:23:13 +010095static struct map_sysfs_entry addr_attribute =
Brandon Philips4f808bc2008-02-19 01:55:05 -080096 __ATTR(addr, S_IRUGO, map_addr_show, NULL);
Hans J. Koche70c4122008-12-06 02:23:13 +010097static struct map_sysfs_entry size_attribute =
Brandon Philips4f808bc2008-02-19 01:55:05 -080098 __ATTR(size, S_IRUGO, map_size_show, NULL);
Hans J. Koche70c4122008-12-06 02:23:13 +010099static struct map_sysfs_entry offset_attribute =
Hans J. Koche2b39df2008-09-18 23:53:18 +0200100 __ATTR(offset, S_IRUGO, map_offset_show, NULL);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100101
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000102static struct attribute *attrs[] = {
Hans J. Koch82057792009-01-07 00:15:39 +0100103 &name_attribute.attr,
Brandon Philips4f808bc2008-02-19 01:55:05 -0800104 &addr_attribute.attr,
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000105 &size_attribute.attr,
Hans J. Koche2b39df2008-09-18 23:53:18 +0200106 &offset_attribute.attr,
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000107 NULL, /* need to NULL terminate the list of attributes */
Hans J. Kochbeafc542006-12-07 10:58:29 +0100108};
109
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000110static void map_release(struct kobject *kobj)
111{
112 struct uio_map *map = to_map(kobj);
113 kfree(map);
114}
115
Brandon Philips4f808bc2008-02-19 01:55:05 -0800116static 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;
Hans J. Koche70c4122008-12-06 02:23:13 +0100121 struct map_sysfs_entry *entry;
Brandon Philips4f808bc2008-02-19 01:55:05 -0800122
Hans J. Koche70c4122008-12-06 02:23:13 +0100123 entry = container_of(attr, struct map_sysfs_entry, attr);
Brandon Philips4f808bc2008-02-19 01:55:05 -0800124
125 if (!entry->show)
126 return -EIO;
127
128 return entry->show(mem, buf);
129}
130
Hans J. Koche70c4122008-12-06 02:23:13 +0100131static struct sysfs_ops map_sysfs_ops = {
Brandon Philips4f808bc2008-02-19 01:55:05 -0800132 .show = map_type_show,
133};
134
Hans J. Kochbeafc542006-12-07 10:58:29 +0100135static struct kobj_type map_attr_type = {
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000136 .release = map_release,
Hans J. Koche70c4122008-12-06 02:23:13 +0100137 .sysfs_ops = &map_sysfs_ops,
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000138 .default_attrs = attrs,
Hans J. Kochbeafc542006-12-07 10:58:29 +0100139};
140
Hans J. Koche70c4122008-12-06 02:23:13 +0100141struct 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
Hans J. Koch82057792009-01-07 00:15:39 +0100147static 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
Hans J. Koche70c4122008-12-06 02:23:13 +0100155static ssize_t portio_start_show(struct uio_port *port, char *buf)
156{
157 return sprintf(buf, "0x%lx\n", port->start);
158}
159
160static ssize_t portio_size_show(struct uio_port *port, char *buf)
161{
162 return sprintf(buf, "0x%lx\n", port->size);
163}
164
165static 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
175struct 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
Hans J. Koch82057792009-01-07 00:15:39 +0100181static struct portio_sysfs_entry portio_name_attribute =
182 __ATTR(name, S_IRUGO, portio_name_show, NULL);
Hans J. Koche70c4122008-12-06 02:23:13 +0100183static struct portio_sysfs_entry portio_start_attribute =
184 __ATTR(start, S_IRUGO, portio_start_show, NULL);
185static struct portio_sysfs_entry portio_size_attribute =
186 __ATTR(size, S_IRUGO, portio_size_show, NULL);
187static struct portio_sysfs_entry portio_porttype_attribute =
188 __ATTR(porttype, S_IRUGO, portio_porttype_show, NULL);
189
190static struct attribute *portio_attrs[] = {
Hans J. Koch82057792009-01-07 00:15:39 +0100191 &portio_name_attribute.attr,
Hans J. Koche70c4122008-12-06 02:23:13 +0100192 &portio_start_attribute.attr,
193 &portio_size_attribute.attr,
194 &portio_porttype_attribute.attr,
195 NULL,
196};
197
198static void portio_release(struct kobject *kobj)
199{
200 struct uio_portio *portio = to_portio(kobj);
201 kfree(portio);
202}
203
204static 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
219static struct sysfs_ops portio_sysfs_ops = {
220 .show = portio_type_show,
221};
222
223static struct kobj_type portio_attr_type = {
224 .release = portio_release,
225 .sysfs_ops = &portio_sysfs_ops,
226 .default_attrs = portio_attrs,
227};
228
Hans J. Kochbeafc542006-12-07 10:58:29 +0100229static 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}
238static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
239
240static 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}
249static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
250
251static 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}
261static DEVICE_ATTR(event, S_IRUGO, show_event, NULL);
262
263static struct attribute *uio_attrs[] = {
264 &dev_attr_name.attr,
265 &dev_attr_version.attr,
266 &dev_attr_event.attr,
267 NULL,
268};
269
270static struct attribute_group uio_attr_grp = {
271 .attrs = uio_attrs,
272};
273
274/*
275 * device functions
276 */
277static int uio_dev_add_attributes(struct uio_device *idev)
278{
279 int ret;
Hans J. Koche70c4122008-12-06 02:23:13 +0100280 int mi, pi;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100281 int map_found = 0;
Hans J. Koche70c4122008-12-06 02:23:13 +0100282 int portio_found = 0;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100283 struct uio_mem *mem;
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000284 struct uio_map *map;
Hans J. Koche70c4122008-12-06 02:23:13 +0100285 struct uio_port *port;
286 struct uio_portio *portio;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100287
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;
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000298 idev->map_dir = kobject_create_and_add("maps",
299 &idev->dev->kobj);
300 if (!idev->map_dir)
Hans J. Koche70c4122008-12-06 02:23:13 +0100301 goto err_map;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100302 }
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000303 map = kzalloc(sizeof(*map), GFP_KERNEL);
304 if (!map)
Hans J. Koche70c4122008-12-06 02:23:13 +0100305 goto err_map;
Greg Kroah-Hartmanf9cb0742007-12-17 23:05:35 -0700306 kobject_init(&map->kobj, &map_attr_type);
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000307 map->mem = mem;
308 mem->map = map;
Greg Kroah-Hartmanb2d6db52007-12-17 23:05:35 -0700309 ret = kobject_add(&map->kobj, idev->map_dir, "map%d", mi);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100310 if (ret)
Hans J. Koche70c4122008-12-06 02:23:13 +0100311 goto err_map;
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000312 ret = kobject_uevent(&map->kobj, KOBJ_ADD);
313 if (ret)
Hans J. Koche70c4122008-12-06 02:23:13 +0100314 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;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100341 }
342
343 return 0;
344
Hans J. Koche70c4122008-12-06 02:23:13 +0100345err_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);
352err_map:
Hans J. Kochbeafc542006-12-07 10:58:29 +0100353 for (mi--; mi>=0; mi--) {
354 mem = &idev->info->mem[mi];
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000355 map = mem->map;
Greg Kroah-Hartmanc10997f2007-12-20 08:13:05 -0800356 kobject_put(&map->kobj);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100357 }
Greg Kroah-Hartmanc10997f2007-12-20 08:13:05 -0800358 kobject_put(idev->map_dir);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100359 sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp);
360err_group:
361 dev_err(idev->dev, "error creating sysfs files (%d)\n", ret);
362 return ret;
363}
364
365static void uio_dev_del_attributes(struct uio_device *idev)
366{
Hans J. Koche70c4122008-12-06 02:23:13 +0100367 int i;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100368 struct uio_mem *mem;
Hans J. Koche70c4122008-12-06 02:23:13 +0100369 struct uio_port *port;
370
371 for (i = 0; i < MAX_UIO_MAPS; i++) {
372 mem = &idev->info->mem[i];
Hans J. Kochbeafc542006-12-07 10:58:29 +0100373 if (mem->size == 0)
374 break;
Greg Kroah-Hartmanc10997f2007-12-20 08:13:05 -0800375 kobject_put(&mem->map->kobj);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100376 }
Greg Kroah-Hartmanc10997f2007-12-20 08:13:05 -0800377 kobject_put(idev->map_dir);
Hans J. Koche70c4122008-12-06 02:23:13 +0100378
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
Hans J. Kochbeafc542006-12-07 10:58:29 +0100387 sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp);
388}
389
390static int uio_get_minor(struct uio_device *idev)
391{
Hans J. Kochbeafc542006-12-07 10:58:29 +0100392 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;
406exit:
407 mutex_unlock(&minor_lock);
408 return retval;
409}
410
411static void uio_free_minor(struct uio_device *idev)
412{
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -0600413 mutex_lock(&minor_lock);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100414 idr_remove(&uio_idr, idev->minor);
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -0600415 mutex_unlock(&minor_lock);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100416}
417
418/**
419 * uio_event_notify - trigger an interrupt event
420 * @info: UIO device capabilities
421 */
422void 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}
430EXPORT_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 */
437static 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
448struct uio_listener {
449 struct uio_device *dev;
450 s32 event_count;
451};
452
453static 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
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -0600459 mutex_lock(&minor_lock);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100460 idev = idr_find(&uio_idr, iminor(inode));
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -0600461 mutex_unlock(&minor_lock);
Jonathan Corbetfbc8a812008-05-15 10:39:37 -0600462 if (!idev) {
463 ret = -ENODEV;
464 goto out;
465 }
Hans J. Kochbeafc542006-12-07 10:58:29 +0100466
Jonathan Corbetfbc8a812008-05-15 10:39:37 -0600467 if (!try_module_get(idev->owner)) {
468 ret = -ENODEV;
469 goto out;
470 }
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200471
Hans J. Kochbeafc542006-12-07 10:58:29 +0100472 listener = kmalloc(sizeof(*listener), GFP_KERNEL);
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200473 if (!listener) {
474 ret = -ENOMEM;
475 goto err_alloc_listener;
476 }
Hans J. Kochbeafc542006-12-07 10:58:29 +0100477
478 listener->dev = idev;
479 listener->event_count = atomic_read(&idev->event);
480 filep->private_data = listener;
481
482 if (idev->info->open) {
Hans J. Kochbeafc542006-12-07 10:58:29 +0100483 ret = idev->info->open(idev->info, inode);
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200484 if (ret)
485 goto err_infoopen;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100486 }
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200487 return 0;
488
489err_infoopen:
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200490 kfree(listener);
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200491
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -0600492err_alloc_listener:
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200493 module_put(idev->owner);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100494
Jonathan Corbetfbc8a812008-05-15 10:39:37 -0600495out:
Hans J. Kochbeafc542006-12-07 10:58:29 +0100496 return ret;
497}
498
499static 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
507static 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
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200513 if (idev->info->release)
Hans J. Kochbeafc542006-12-07 10:58:29 +0100514 ret = idev->info->release(idev->info, inode);
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200515
516 module_put(idev->owner);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100517 kfree(listener);
518 return ret;
519}
520
521static 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
535static 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
Hans J. Koch328a14e2008-05-23 13:50:14 +0200584static 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
Hans J. Kochbeafc542006-12-07 10:58:29 +0100609static 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
623static 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
629static 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
Nick Piggina18b6302008-02-06 01:37:35 -0800635static int uio_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
Hans J. Kochbeafc542006-12-07 10:58:29 +0100636{
637 struct uio_device *idev = vma->vm_private_data;
Nick Piggina18b6302008-02-06 01:37:35 -0800638 struct page *page;
Andrew G. Harvey02683ff2008-09-24 01:10:02 +0200639 unsigned long offset;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100640
641 int mi = uio_find_mem_index(vma);
642 if (mi < 0)
Nick Piggina18b6302008-02-06 01:37:35 -0800643 return VM_FAULT_SIGBUS;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100644
Andrew G. Harvey02683ff2008-09-24 01:10:02 +0200645 /*
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
Hans J. Kochbeafc542006-12-07 10:58:29 +0100651 if (idev->info->mem[mi].memtype == UIO_MEM_LOGICAL)
Andrew G. Harvey02683ff2008-09-24 01:10:02 +0200652 page = virt_to_page(idev->info->mem[mi].addr + offset);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100653 else
Andrew G. Harvey02683ff2008-09-24 01:10:02 +0200654 page = vmalloc_to_page((void *)idev->info->mem[mi].addr
655 + offset);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100656 get_page(page);
Nick Piggina18b6302008-02-06 01:37:35 -0800657 vmf->page = page;
658 return 0;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100659}
660
661static struct vm_operations_struct uio_vm_ops = {
662 .open = uio_vma_open,
663 .close = uio_vma_close,
Nick Piggina18b6302008-02-06 01:37:35 -0800664 .fault = uio_vma_fault,
Hans J. Kochbeafc542006-12-07 10:58:29 +0100665};
666
667static 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;
675
Jean-Samuel Chenardc9698d6b2008-03-14 11:28:36 +0100676 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
677
Hans J. Kochbeafc542006-12-07 10:58:29 +0100678 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
685static 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
693static 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;
Ian Abbott6da2d372009-02-24 17:22:59 +0000711 actual_pages = ((idev->info->mem[mi].addr & ~PAGE_MASK)
712 + idev->info->mem[mi].size + PAGE_SIZE -1) >> PAGE_SHIFT;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100713 if (requested_pages > actual_pages)
714 return -EINVAL;
715
716 if (idev->info->mmap) {
Hans J. Kochbeafc542006-12-07 10:58:29 +0100717 ret = idev->info->mmap(idev->info, vma);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100718 return ret;
719 }
720
721 switch (idev->info->mem[mi].memtype) {
722 case UIO_MEM_PHYS:
723 return uio_mmap_physical(vma);
724 case UIO_MEM_LOGICAL:
725 case UIO_MEM_VIRTUAL:
726 return uio_mmap_logical(vma);
727 default:
728 return -EINVAL;
729 }
730}
731
Jan Engelhardt4f014692008-01-22 20:50:54 +0100732static const struct file_operations uio_fops = {
Hans J. Kochbeafc542006-12-07 10:58:29 +0100733 .owner = THIS_MODULE,
734 .open = uio_open,
735 .release = uio_release,
736 .read = uio_read,
Hans J. Koch328a14e2008-05-23 13:50:14 +0200737 .write = uio_write,
Hans J. Kochbeafc542006-12-07 10:58:29 +0100738 .mmap = uio_mmap,
739 .poll = uio_poll,
740 .fasync = uio_fasync,
741};
742
743static int uio_major_init(void)
744{
745 uio_major = register_chrdev(0, "uio", &uio_fops);
746 if (uio_major < 0)
747 return uio_major;
748 return 0;
749}
750
751static void uio_major_cleanup(void)
752{
753 unregister_chrdev(uio_major, "uio");
754}
755
756static int init_uio_class(void)
757{
758 int ret = 0;
759
760 if (uio_class != NULL) {
761 kref_get(&uio_class->kref);
762 goto exit;
763 }
764
765 /* This is the first time in here, set everything up properly */
766 ret = uio_major_init();
767 if (ret)
768 goto exit;
769
770 uio_class = kzalloc(sizeof(*uio_class), GFP_KERNEL);
771 if (!uio_class) {
772 ret = -ENOMEM;
773 goto err_kzalloc;
774 }
775
776 kref_init(&uio_class->kref);
777 uio_class->class = class_create(THIS_MODULE, "uio");
778 if (IS_ERR(uio_class->class)) {
779 ret = IS_ERR(uio_class->class);
780 printk(KERN_ERR "class_create failed for uio\n");
781 goto err_class_create;
782 }
783 return 0;
784
785err_class_create:
786 kfree(uio_class);
787 uio_class = NULL;
788err_kzalloc:
789 uio_major_cleanup();
790exit:
791 return ret;
792}
793
794static void release_uio_class(struct kref *kref)
795{
796 /* Ok, we cheat as we know we only have one uio_class */
797 class_destroy(uio_class->class);
798 kfree(uio_class);
799 uio_major_cleanup();
800 uio_class = NULL;
801}
802
803static void uio_class_destroy(void)
804{
805 if (uio_class)
806 kref_put(&uio_class->kref, release_uio_class);
807}
808
809/**
810 * uio_register_device - register a new userspace IO device
811 * @owner: module that creates the new device
812 * @parent: parent device
813 * @info: UIO device capabilities
814 *
815 * returns zero on success or a negative error code.
816 */
817int __uio_register_device(struct module *owner,
818 struct device *parent,
819 struct uio_info *info)
820{
821 struct uio_device *idev;
822 int ret = 0;
823
824 if (!parent || !info || !info->name || !info->version)
825 return -EINVAL;
826
827 info->uio_dev = NULL;
828
829 ret = init_uio_class();
830 if (ret)
831 return ret;
832
833 idev = kzalloc(sizeof(*idev), GFP_KERNEL);
834 if (!idev) {
835 ret = -ENOMEM;
836 goto err_kzalloc;
837 }
838
839 idev->owner = owner;
840 idev->info = info;
841 init_waitqueue_head(&idev->wait);
842 atomic_set(&idev->event, 0);
843
844 ret = uio_get_minor(idev);
845 if (ret)
846 goto err_get_minor;
847
Greg Kroah-Hartmana9b12612008-07-21 20:03:34 -0700848 idev->dev = device_create(uio_class->class, parent,
849 MKDEV(uio_major, idev->minor), idev,
850 "uio%d", idev->minor);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100851 if (IS_ERR(idev->dev)) {
852 printk(KERN_ERR "UIO: device register failed\n");
853 ret = PTR_ERR(idev->dev);
854 goto err_device_create;
855 }
Hans J. Kochbeafc542006-12-07 10:58:29 +0100856
857 ret = uio_dev_add_attributes(idev);
858 if (ret)
859 goto err_uio_dev_add_attributes;
860
861 info->uio_dev = idev;
862
863 if (idev->info->irq >= 0) {
864 ret = request_irq(idev->info->irq, uio_interrupt,
865 idev->info->irq_flags, idev->info->name, idev);
866 if (ret)
867 goto err_request_irq;
868 }
869
870 return 0;
871
872err_request_irq:
873 uio_dev_del_attributes(idev);
874err_uio_dev_add_attributes:
875 device_destroy(uio_class->class, MKDEV(uio_major, idev->minor));
876err_device_create:
877 uio_free_minor(idev);
878err_get_minor:
879 kfree(idev);
880err_kzalloc:
881 uio_class_destroy();
882 return ret;
883}
884EXPORT_SYMBOL_GPL(__uio_register_device);
885
886/**
887 * uio_unregister_device - unregister a industrial IO device
888 * @info: UIO device capabilities
889 *
890 */
891void uio_unregister_device(struct uio_info *info)
892{
893 struct uio_device *idev;
894
895 if (!info || !info->uio_dev)
896 return;
897
898 idev = info->uio_dev;
899
900 uio_free_minor(idev);
901
902 if (info->irq >= 0)
903 free_irq(info->irq, idev);
904
905 uio_dev_del_attributes(idev);
906
907 dev_set_drvdata(idev->dev, NULL);
908 device_destroy(uio_class->class, MKDEV(uio_major, idev->minor));
909 kfree(idev);
910 uio_class_destroy();
911
912 return;
913}
914EXPORT_SYMBOL_GPL(uio_unregister_device);
915
916static int __init uio_init(void)
917{
918 return 0;
919}
920
921static void __exit uio_exit(void)
922{
923}
924
925module_init(uio_init)
926module_exit(uio_exit)
927MODULE_LICENSE("GPL v2");