blob: 51fe1795d5a8197678a5a00763f62e8a9fe59183 [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>
Hans J. Koch318af552010-10-30 00:36:47 +02006 * Copyright(C) 2006, Hans J. Koch <hjk@hansjkoch.de>
Hans J. Kochbeafc542006-12-07 10:58:29 +01007 * 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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090020#include <linux/slab.h>
Hans J. Kochbeafc542006-12-07 10:58:29 +010021#include <linux/mm.h>
22#include <linux/idr.h>
Alexey Dobriyand43c36d2009-10-07 17:09:06 +040023#include <linux/sched.h>
Hans J. Kochbeafc542006-12-07 10:58:29 +010024#include <linux/string.h>
25#include <linux/kobject.h>
Eric W. Biederman91960a42010-09-14 11:38:06 -070026#include <linux/cdev.h>
Hans J. Kochbeafc542006-12-07 10:58:29 +010027#include <linux/uio_driver.h>
28
Eric W. Biederman91960a42010-09-14 11:38:06 -070029#define UIO_MAX_DEVICES (1U << MINORBITS)
Hans J. Kochbeafc542006-12-07 10:58:29 +010030
31struct uio_device {
32 struct module *owner;
33 struct device *dev;
34 int minor;
35 atomic_t event;
36 struct fasync_struct *async_queue;
37 wait_queue_head_t wait;
38 int vma_count;
39 struct uio_info *info;
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +000040 struct kobject *map_dir;
Hans J. Koche70c4122008-12-06 02:23:13 +010041 struct kobject *portio_dir;
Hans J. Kochbeafc542006-12-07 10:58:29 +010042};
43
44static int uio_major;
Eric W. Biederman91960a42010-09-14 11:38:06 -070045static struct cdev *uio_cdev;
Hans J. Kochbeafc542006-12-07 10:58:29 +010046static DEFINE_IDR(uio_idr);
Jan Engelhardt4f014692008-01-22 20:50:54 +010047static const struct file_operations uio_fops;
Hans J. Kochbeafc542006-12-07 10:58:29 +010048
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -060049/* Protect idr accesses */
50static DEFINE_MUTEX(minor_lock);
51
Hans J. Kochbeafc542006-12-07 10:58:29 +010052/*
53 * attributes
54 */
55
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +000056struct uio_map {
57 struct kobject kobj;
58 struct uio_mem *mem;
Hans J. Kochbeafc542006-12-07 10:58:29 +010059};
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +000060#define to_map(map) container_of(map, struct uio_map, kobj)
Hans J. Kochbeafc542006-12-07 10:58:29 +010061
Hans J. Koch82057792009-01-07 00:15:39 +010062static ssize_t map_name_show(struct uio_mem *mem, char *buf)
63{
64 if (unlikely(!mem->name))
65 mem->name = "";
66
67 return sprintf(buf, "%s\n", mem->name);
68}
69
Brandon Philips4f808bc2008-02-19 01:55:05 -080070static ssize_t map_addr_show(struct uio_mem *mem, char *buf)
Hans J. Kochbeafc542006-12-07 10:58:29 +010071{
Brandon Philips4f808bc2008-02-19 01:55:05 -080072 return sprintf(buf, "0x%lx\n", mem->addr);
Hans J. Kochbeafc542006-12-07 10:58:29 +010073}
74
Brandon Philips4f808bc2008-02-19 01:55:05 -080075static ssize_t map_size_show(struct uio_mem *mem, char *buf)
76{
77 return sprintf(buf, "0x%lx\n", mem->size);
78}
79
Hans J. Koche2b39df2008-09-18 23:53:18 +020080static ssize_t map_offset_show(struct uio_mem *mem, char *buf)
81{
82 return sprintf(buf, "0x%lx\n", mem->addr & ~PAGE_MASK);
83}
84
Hans J. Koche70c4122008-12-06 02:23:13 +010085struct map_sysfs_entry {
Brandon Philips4f808bc2008-02-19 01:55:05 -080086 struct attribute attr;
87 ssize_t (*show)(struct uio_mem *, char *);
88 ssize_t (*store)(struct uio_mem *, const char *, size_t);
89};
90
Hans J. Koch82057792009-01-07 00:15:39 +010091static struct map_sysfs_entry name_attribute =
92 __ATTR(name, S_IRUGO, map_name_show, NULL);
Hans J. Koche70c4122008-12-06 02:23:13 +010093static struct map_sysfs_entry addr_attribute =
Brandon Philips4f808bc2008-02-19 01:55:05 -080094 __ATTR(addr, S_IRUGO, map_addr_show, NULL);
Hans J. Koche70c4122008-12-06 02:23:13 +010095static struct map_sysfs_entry size_attribute =
Brandon Philips4f808bc2008-02-19 01:55:05 -080096 __ATTR(size, S_IRUGO, map_size_show, NULL);
Hans J. Koche70c4122008-12-06 02:23:13 +010097static struct map_sysfs_entry offset_attribute =
Hans J. Koche2b39df2008-09-18 23:53:18 +020098 __ATTR(offset, S_IRUGO, map_offset_show, NULL);
Hans J. Kochbeafc542006-12-07 10:58:29 +010099
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000100static struct attribute *attrs[] = {
Hans J. Koch82057792009-01-07 00:15:39 +0100101 &name_attribute.attr,
Brandon Philips4f808bc2008-02-19 01:55:05 -0800102 &addr_attribute.attr,
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000103 &size_attribute.attr,
Hans J. Koche2b39df2008-09-18 23:53:18 +0200104 &offset_attribute.attr,
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000105 NULL, /* need to NULL terminate the list of attributes */
Hans J. Kochbeafc542006-12-07 10:58:29 +0100106};
107
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000108static void map_release(struct kobject *kobj)
109{
110 struct uio_map *map = to_map(kobj);
111 kfree(map);
112}
113
Brandon Philips4f808bc2008-02-19 01:55:05 -0800114static ssize_t map_type_show(struct kobject *kobj, struct attribute *attr,
115 char *buf)
116{
117 struct uio_map *map = to_map(kobj);
118 struct uio_mem *mem = map->mem;
Hans J. Koche70c4122008-12-06 02:23:13 +0100119 struct map_sysfs_entry *entry;
Brandon Philips4f808bc2008-02-19 01:55:05 -0800120
Hans J. Koche70c4122008-12-06 02:23:13 +0100121 entry = container_of(attr, struct map_sysfs_entry, attr);
Brandon Philips4f808bc2008-02-19 01:55:05 -0800122
123 if (!entry->show)
124 return -EIO;
125
126 return entry->show(mem, buf);
127}
128
Emese Revfy52cf25d2010-01-19 02:58:23 +0100129static const struct sysfs_ops map_sysfs_ops = {
Brandon Philips4f808bc2008-02-19 01:55:05 -0800130 .show = map_type_show,
131};
132
Hans J. Kochbeafc542006-12-07 10:58:29 +0100133static struct kobj_type map_attr_type = {
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000134 .release = map_release,
Hans J. Koche70c4122008-12-06 02:23:13 +0100135 .sysfs_ops = &map_sysfs_ops,
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000136 .default_attrs = attrs,
Hans J. Kochbeafc542006-12-07 10:58:29 +0100137};
138
Hans J. Koche70c4122008-12-06 02:23:13 +0100139struct uio_portio {
140 struct kobject kobj;
141 struct uio_port *port;
142};
143#define to_portio(portio) container_of(portio, struct uio_portio, kobj)
144
Hans J. Koch82057792009-01-07 00:15:39 +0100145static ssize_t portio_name_show(struct uio_port *port, char *buf)
146{
147 if (unlikely(!port->name))
148 port->name = "";
149
150 return sprintf(buf, "%s\n", port->name);
151}
152
Hans J. Koche70c4122008-12-06 02:23:13 +0100153static ssize_t portio_start_show(struct uio_port *port, char *buf)
154{
155 return sprintf(buf, "0x%lx\n", port->start);
156}
157
158static ssize_t portio_size_show(struct uio_port *port, char *buf)
159{
160 return sprintf(buf, "0x%lx\n", port->size);
161}
162
163static ssize_t portio_porttype_show(struct uio_port *port, char *buf)
164{
165 const char *porttypes[] = {"none", "x86", "gpio", "other"};
166
167 if ((port->porttype < 0) || (port->porttype > UIO_PORT_OTHER))
168 return -EINVAL;
169
170 return sprintf(buf, "port_%s\n", porttypes[port->porttype]);
171}
172
173struct portio_sysfs_entry {
174 struct attribute attr;
175 ssize_t (*show)(struct uio_port *, char *);
176 ssize_t (*store)(struct uio_port *, const char *, size_t);
177};
178
Hans J. Koch82057792009-01-07 00:15:39 +0100179static struct portio_sysfs_entry portio_name_attribute =
180 __ATTR(name, S_IRUGO, portio_name_show, NULL);
Hans J. Koche70c4122008-12-06 02:23:13 +0100181static struct portio_sysfs_entry portio_start_attribute =
182 __ATTR(start, S_IRUGO, portio_start_show, NULL);
183static struct portio_sysfs_entry portio_size_attribute =
184 __ATTR(size, S_IRUGO, portio_size_show, NULL);
185static struct portio_sysfs_entry portio_porttype_attribute =
186 __ATTR(porttype, S_IRUGO, portio_porttype_show, NULL);
187
188static struct attribute *portio_attrs[] = {
Hans J. Koch82057792009-01-07 00:15:39 +0100189 &portio_name_attribute.attr,
Hans J. Koche70c4122008-12-06 02:23:13 +0100190 &portio_start_attribute.attr,
191 &portio_size_attribute.attr,
192 &portio_porttype_attribute.attr,
193 NULL,
194};
195
196static void portio_release(struct kobject *kobj)
197{
198 struct uio_portio *portio = to_portio(kobj);
199 kfree(portio);
200}
201
202static ssize_t portio_type_show(struct kobject *kobj, struct attribute *attr,
203 char *buf)
204{
205 struct uio_portio *portio = to_portio(kobj);
206 struct uio_port *port = portio->port;
207 struct portio_sysfs_entry *entry;
208
209 entry = container_of(attr, struct portio_sysfs_entry, attr);
210
211 if (!entry->show)
212 return -EIO;
213
214 return entry->show(port, buf);
215}
216
Emese Revfy52cf25d2010-01-19 02:58:23 +0100217static const struct sysfs_ops portio_sysfs_ops = {
Hans J. Koche70c4122008-12-06 02:23:13 +0100218 .show = portio_type_show,
219};
220
221static struct kobj_type portio_attr_type = {
222 .release = portio_release,
223 .sysfs_ops = &portio_sysfs_ops,
224 .default_attrs = portio_attrs,
225};
226
Hans J. Kochbeafc542006-12-07 10:58:29 +0100227static ssize_t show_name(struct device *dev,
228 struct device_attribute *attr, char *buf)
229{
230 struct uio_device *idev = dev_get_drvdata(dev);
Eric W. Biederman70a91562010-09-14 11:36:54 -0700231 return sprintf(buf, "%s\n", idev->info->name);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100232}
Hans J. Kochbeafc542006-12-07 10:58:29 +0100233
234static ssize_t show_version(struct device *dev,
235 struct device_attribute *attr, char *buf)
236{
237 struct uio_device *idev = dev_get_drvdata(dev);
Eric W. Biederman70a91562010-09-14 11:36:54 -0700238 return sprintf(buf, "%s\n", idev->info->version);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100239}
Hans J. Kochbeafc542006-12-07 10:58:29 +0100240
241static ssize_t show_event(struct device *dev,
242 struct device_attribute *attr, char *buf)
243{
244 struct uio_device *idev = dev_get_drvdata(dev);
Eric W. Biederman70a91562010-09-14 11:36:54 -0700245 return sprintf(buf, "%u\n", (unsigned int)atomic_read(&idev->event));
Hans J. Kochbeafc542006-12-07 10:58:29 +0100246}
Hans J. Kochbeafc542006-12-07 10:58:29 +0100247
Eric W. Biedermanc66fdab2010-09-14 11:38:36 -0700248static struct device_attribute uio_class_attributes[] = {
249 __ATTR(name, S_IRUGO, show_name, NULL),
250 __ATTR(version, S_IRUGO, show_version, NULL),
251 __ATTR(event, S_IRUGO, show_event, NULL),
252 {}
Hans J. Kochbeafc542006-12-07 10:58:29 +0100253};
254
Eric W. Biedermanc66fdab2010-09-14 11:38:36 -0700255/* UIO class infrastructure */
256static struct class uio_class = {
257 .name = "uio",
258 .dev_attrs = uio_class_attributes,
Hans J. Kochbeafc542006-12-07 10:58:29 +0100259};
260
261/*
262 * device functions
263 */
264static int uio_dev_add_attributes(struct uio_device *idev)
265{
266 int ret;
Hans J. Koche70c4122008-12-06 02:23:13 +0100267 int mi, pi;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100268 int map_found = 0;
Hans J. Koche70c4122008-12-06 02:23:13 +0100269 int portio_found = 0;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100270 struct uio_mem *mem;
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000271 struct uio_map *map;
Hans J. Koche70c4122008-12-06 02:23:13 +0100272 struct uio_port *port;
273 struct uio_portio *portio;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100274
Hans J. Kochbeafc542006-12-07 10:58:29 +0100275 for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
276 mem = &idev->info->mem[mi];
277 if (mem->size == 0)
278 break;
279 if (!map_found) {
280 map_found = 1;
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000281 idev->map_dir = kobject_create_and_add("maps",
282 &idev->dev->kobj);
283 if (!idev->map_dir)
Hans J. Koche70c4122008-12-06 02:23:13 +0100284 goto err_map;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100285 }
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000286 map = kzalloc(sizeof(*map), GFP_KERNEL);
287 if (!map)
Hans J. Koche70c4122008-12-06 02:23:13 +0100288 goto err_map;
Greg Kroah-Hartmanf9cb0742007-12-17 23:05:35 -0700289 kobject_init(&map->kobj, &map_attr_type);
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000290 map->mem = mem;
291 mem->map = map;
Greg Kroah-Hartmanb2d6db52007-12-17 23:05:35 -0700292 ret = kobject_add(&map->kobj, idev->map_dir, "map%d", mi);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100293 if (ret)
Hans J. Koche70c4122008-12-06 02:23:13 +0100294 goto err_map;
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000295 ret = kobject_uevent(&map->kobj, KOBJ_ADD);
296 if (ret)
Hans J. Koche70c4122008-12-06 02:23:13 +0100297 goto err_map;
298 }
299
300 for (pi = 0; pi < MAX_UIO_PORT_REGIONS; pi++) {
301 port = &idev->info->port[pi];
302 if (port->size == 0)
303 break;
304 if (!portio_found) {
305 portio_found = 1;
306 idev->portio_dir = kobject_create_and_add("portio",
307 &idev->dev->kobj);
308 if (!idev->portio_dir)
309 goto err_portio;
310 }
311 portio = kzalloc(sizeof(*portio), GFP_KERNEL);
312 if (!portio)
313 goto err_portio;
314 kobject_init(&portio->kobj, &portio_attr_type);
315 portio->port = port;
316 port->portio = portio;
317 ret = kobject_add(&portio->kobj, idev->portio_dir,
318 "port%d", pi);
319 if (ret)
320 goto err_portio;
321 ret = kobject_uevent(&portio->kobj, KOBJ_ADD);
322 if (ret)
323 goto err_portio;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100324 }
325
326 return 0;
327
Hans J. Koche70c4122008-12-06 02:23:13 +0100328err_portio:
329 for (pi--; pi >= 0; pi--) {
330 port = &idev->info->port[pi];
331 portio = port->portio;
332 kobject_put(&portio->kobj);
333 }
334 kobject_put(idev->portio_dir);
335err_map:
Hans J. Kochbeafc542006-12-07 10:58:29 +0100336 for (mi--; mi>=0; mi--) {
337 mem = &idev->info->mem[mi];
Greg Kroah-Hartman81e7c6a2007-12-04 22:41:54 +0000338 map = mem->map;
Greg Kroah-Hartmanc10997f2007-12-20 08:13:05 -0800339 kobject_put(&map->kobj);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100340 }
Greg Kroah-Hartmanc10997f2007-12-20 08:13:05 -0800341 kobject_put(idev->map_dir);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100342 dev_err(idev->dev, "error creating sysfs files (%d)\n", ret);
343 return ret;
344}
345
346static void uio_dev_del_attributes(struct uio_device *idev)
347{
Hans J. Koche70c4122008-12-06 02:23:13 +0100348 int i;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100349 struct uio_mem *mem;
Hans J. Koche70c4122008-12-06 02:23:13 +0100350 struct uio_port *port;
351
352 for (i = 0; i < MAX_UIO_MAPS; i++) {
353 mem = &idev->info->mem[i];
Hans J. Kochbeafc542006-12-07 10:58:29 +0100354 if (mem->size == 0)
355 break;
Greg Kroah-Hartmanc10997f2007-12-20 08:13:05 -0800356 kobject_put(&mem->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. Koche70c4122008-12-06 02:23:13 +0100359
360 for (i = 0; i < MAX_UIO_PORT_REGIONS; i++) {
361 port = &idev->info->port[i];
362 if (port->size == 0)
363 break;
364 kobject_put(&port->portio->kobj);
365 }
366 kobject_put(idev->portio_dir);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100367}
368
369static int uio_get_minor(struct uio_device *idev)
370{
Hans J. Kochbeafc542006-12-07 10:58:29 +0100371 int retval = -ENOMEM;
372 int id;
373
374 mutex_lock(&minor_lock);
375 if (idr_pre_get(&uio_idr, GFP_KERNEL) == 0)
376 goto exit;
377
378 retval = idr_get_new(&uio_idr, idev, &id);
379 if (retval < 0) {
380 if (retval == -EAGAIN)
381 retval = -ENOMEM;
382 goto exit;
383 }
384 idev->minor = id & MAX_ID_MASK;
385exit:
386 mutex_unlock(&minor_lock);
387 return retval;
388}
389
390static void uio_free_minor(struct uio_device *idev)
391{
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -0600392 mutex_lock(&minor_lock);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100393 idr_remove(&uio_idr, idev->minor);
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -0600394 mutex_unlock(&minor_lock);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100395}
396
397/**
398 * uio_event_notify - trigger an interrupt event
399 * @info: UIO device capabilities
400 */
401void uio_event_notify(struct uio_info *info)
402{
403 struct uio_device *idev = info->uio_dev;
404
405 atomic_inc(&idev->event);
406 wake_up_interruptible(&idev->wait);
407 kill_fasync(&idev->async_queue, SIGIO, POLL_IN);
408}
409EXPORT_SYMBOL_GPL(uio_event_notify);
410
411/**
412 * uio_interrupt - hardware interrupt handler
413 * @irq: IRQ number, can be UIO_IRQ_CYCLIC for cyclic timer
414 * @dev_id: Pointer to the devices uio_device structure
415 */
416static irqreturn_t uio_interrupt(int irq, void *dev_id)
417{
418 struct uio_device *idev = (struct uio_device *)dev_id;
419 irqreturn_t ret = idev->info->handler(irq, idev->info);
420
421 if (ret == IRQ_HANDLED)
422 uio_event_notify(idev->info);
423
424 return ret;
425}
426
427struct uio_listener {
428 struct uio_device *dev;
429 s32 event_count;
430};
431
432static int uio_open(struct inode *inode, struct file *filep)
433{
434 struct uio_device *idev;
435 struct uio_listener *listener;
436 int ret = 0;
437
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -0600438 mutex_lock(&minor_lock);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100439 idev = idr_find(&uio_idr, iminor(inode));
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -0600440 mutex_unlock(&minor_lock);
Jonathan Corbetfbc8a812008-05-15 10:39:37 -0600441 if (!idev) {
442 ret = -ENODEV;
443 goto out;
444 }
Hans J. Kochbeafc542006-12-07 10:58:29 +0100445
Jonathan Corbetfbc8a812008-05-15 10:39:37 -0600446 if (!try_module_get(idev->owner)) {
447 ret = -ENODEV;
448 goto out;
449 }
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200450
Hans J. Kochbeafc542006-12-07 10:58:29 +0100451 listener = kmalloc(sizeof(*listener), GFP_KERNEL);
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200452 if (!listener) {
453 ret = -ENOMEM;
454 goto err_alloc_listener;
455 }
Hans J. Kochbeafc542006-12-07 10:58:29 +0100456
457 listener->dev = idev;
458 listener->event_count = atomic_read(&idev->event);
459 filep->private_data = listener;
460
461 if (idev->info->open) {
Hans J. Kochbeafc542006-12-07 10:58:29 +0100462 ret = idev->info->open(idev->info, inode);
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200463 if (ret)
464 goto err_infoopen;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100465 }
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200466 return 0;
467
468err_infoopen:
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200469 kfree(listener);
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200470
Jonathan Corbet0d4a7bc2008-08-26 17:15:45 -0600471err_alloc_listener:
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200472 module_put(idev->owner);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100473
Jonathan Corbetfbc8a812008-05-15 10:39:37 -0600474out:
Hans J. Kochbeafc542006-12-07 10:58:29 +0100475 return ret;
476}
477
478static int uio_fasync(int fd, struct file *filep, int on)
479{
480 struct uio_listener *listener = filep->private_data;
481 struct uio_device *idev = listener->dev;
482
483 return fasync_helper(fd, filep, on, &idev->async_queue);
484}
485
486static int uio_release(struct inode *inode, struct file *filep)
487{
488 int ret = 0;
489 struct uio_listener *listener = filep->private_data;
490 struct uio_device *idev = listener->dev;
491
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200492 if (idev->info->release)
Hans J. Kochbeafc542006-12-07 10:58:29 +0100493 ret = idev->info->release(idev->info, inode);
Uwe Kleine-König610ad502008-04-11 11:07:39 +0200494
495 module_put(idev->owner);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100496 kfree(listener);
497 return ret;
498}
499
500static unsigned int uio_poll(struct file *filep, poll_table *wait)
501{
502 struct uio_listener *listener = filep->private_data;
503 struct uio_device *idev = listener->dev;
504
Eric W. Biederman6427a762010-09-14 11:37:36 -0700505 if (!idev->info->irq)
Hans J. Kochbeafc542006-12-07 10:58:29 +0100506 return -EIO;
507
508 poll_wait(filep, &idev->wait, wait);
509 if (listener->event_count != atomic_read(&idev->event))
510 return POLLIN | POLLRDNORM;
511 return 0;
512}
513
514static ssize_t uio_read(struct file *filep, char __user *buf,
515 size_t count, loff_t *ppos)
516{
517 struct uio_listener *listener = filep->private_data;
518 struct uio_device *idev = listener->dev;
519 DECLARE_WAITQUEUE(wait, current);
520 ssize_t retval;
521 s32 event_count;
522
Eric W. Biederman6427a762010-09-14 11:37:36 -0700523 if (!idev->info->irq)
Hans J. Kochbeafc542006-12-07 10:58:29 +0100524 return -EIO;
525
526 if (count != sizeof(s32))
527 return -EINVAL;
528
529 add_wait_queue(&idev->wait, &wait);
530
531 do {
532 set_current_state(TASK_INTERRUPTIBLE);
533
534 event_count = atomic_read(&idev->event);
535 if (event_count != listener->event_count) {
536 if (copy_to_user(buf, &event_count, count))
537 retval = -EFAULT;
538 else {
539 listener->event_count = event_count;
540 retval = count;
541 }
542 break;
543 }
544
545 if (filep->f_flags & O_NONBLOCK) {
546 retval = -EAGAIN;
547 break;
548 }
549
550 if (signal_pending(current)) {
551 retval = -ERESTARTSYS;
552 break;
553 }
554 schedule();
555 } while (1);
556
557 __set_current_state(TASK_RUNNING);
558 remove_wait_queue(&idev->wait, &wait);
559
560 return retval;
561}
562
Hans J. Koch328a14e2008-05-23 13:50:14 +0200563static ssize_t uio_write(struct file *filep, const char __user *buf,
564 size_t count, loff_t *ppos)
565{
566 struct uio_listener *listener = filep->private_data;
567 struct uio_device *idev = listener->dev;
568 ssize_t retval;
569 s32 irq_on;
570
Eric W. Biederman6427a762010-09-14 11:37:36 -0700571 if (!idev->info->irq)
Hans J. Koch328a14e2008-05-23 13:50:14 +0200572 return -EIO;
573
574 if (count != sizeof(s32))
575 return -EINVAL;
576
577 if (!idev->info->irqcontrol)
578 return -ENOSYS;
579
580 if (copy_from_user(&irq_on, buf, count))
581 return -EFAULT;
582
583 retval = idev->info->irqcontrol(idev->info, irq_on);
584
585 return retval ? retval : sizeof(s32);
586}
587
Hans J. Kochbeafc542006-12-07 10:58:29 +0100588static int uio_find_mem_index(struct vm_area_struct *vma)
589{
590 int mi;
591 struct uio_device *idev = vma->vm_private_data;
592
593 for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
594 if (idev->info->mem[mi].size == 0)
595 return -1;
596 if (vma->vm_pgoff == mi)
597 return mi;
598 }
599 return -1;
600}
601
602static void uio_vma_open(struct vm_area_struct *vma)
603{
604 struct uio_device *idev = vma->vm_private_data;
605 idev->vma_count++;
606}
607
608static void uio_vma_close(struct vm_area_struct *vma)
609{
610 struct uio_device *idev = vma->vm_private_data;
611 idev->vma_count--;
612}
613
Nick Piggina18b6302008-02-06 01:37:35 -0800614static int uio_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
Hans J. Kochbeafc542006-12-07 10:58:29 +0100615{
616 struct uio_device *idev = vma->vm_private_data;
Nick Piggina18b6302008-02-06 01:37:35 -0800617 struct page *page;
Andrew G. Harvey02683ff2008-09-24 01:10:02 +0200618 unsigned long offset;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100619
620 int mi = uio_find_mem_index(vma);
621 if (mi < 0)
Nick Piggina18b6302008-02-06 01:37:35 -0800622 return VM_FAULT_SIGBUS;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100623
Andrew G. Harvey02683ff2008-09-24 01:10:02 +0200624 /*
625 * We need to subtract mi because userspace uses offset = N*PAGE_SIZE
626 * to use mem[N].
627 */
628 offset = (vmf->pgoff - mi) << PAGE_SHIFT;
629
Hans J. Kochbeafc542006-12-07 10:58:29 +0100630 if (idev->info->mem[mi].memtype == UIO_MEM_LOGICAL)
Andrew G. Harvey02683ff2008-09-24 01:10:02 +0200631 page = virt_to_page(idev->info->mem[mi].addr + offset);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100632 else
Andrew G. Harvey02683ff2008-09-24 01:10:02 +0200633 page = vmalloc_to_page((void *)idev->info->mem[mi].addr
634 + offset);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100635 get_page(page);
Nick Piggina18b6302008-02-06 01:37:35 -0800636 vmf->page = page;
637 return 0;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100638}
639
Alexey Dobriyanf0f37e22009-09-27 22:29:37 +0400640static const struct vm_operations_struct uio_vm_ops = {
Hans J. Kochbeafc542006-12-07 10:58:29 +0100641 .open = uio_vma_open,
642 .close = uio_vma_close,
Nick Piggina18b6302008-02-06 01:37:35 -0800643 .fault = uio_vma_fault,
Hans J. Kochbeafc542006-12-07 10:58:29 +0100644};
645
646static int uio_mmap_physical(struct vm_area_struct *vma)
647{
648 struct uio_device *idev = vma->vm_private_data;
649 int mi = uio_find_mem_index(vma);
650 if (mi < 0)
651 return -EINVAL;
652
653 vma->vm_flags |= VM_IO | VM_RESERVED;
654
Jean-Samuel Chenardc9698d62008-03-14 11:28:36 +0100655 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
656
Hans J. Kochbeafc542006-12-07 10:58:29 +0100657 return remap_pfn_range(vma,
658 vma->vm_start,
659 idev->info->mem[mi].addr >> PAGE_SHIFT,
660 vma->vm_end - vma->vm_start,
661 vma->vm_page_prot);
662}
663
664static int uio_mmap_logical(struct vm_area_struct *vma)
665{
666 vma->vm_flags |= VM_RESERVED;
667 vma->vm_ops = &uio_vm_ops;
668 uio_vma_open(vma);
669 return 0;
670}
671
672static int uio_mmap(struct file *filep, struct vm_area_struct *vma)
673{
674 struct uio_listener *listener = filep->private_data;
675 struct uio_device *idev = listener->dev;
676 int mi;
677 unsigned long requested_pages, actual_pages;
678 int ret = 0;
679
680 if (vma->vm_end < vma->vm_start)
681 return -EINVAL;
682
683 vma->vm_private_data = idev;
684
685 mi = uio_find_mem_index(vma);
686 if (mi < 0)
687 return -EINVAL;
688
689 requested_pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
Ian Abbott6da2d372009-02-24 17:22:59 +0000690 actual_pages = ((idev->info->mem[mi].addr & ~PAGE_MASK)
691 + idev->info->mem[mi].size + PAGE_SIZE -1) >> PAGE_SHIFT;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100692 if (requested_pages > actual_pages)
693 return -EINVAL;
694
695 if (idev->info->mmap) {
Hans J. Kochbeafc542006-12-07 10:58:29 +0100696 ret = idev->info->mmap(idev->info, vma);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100697 return ret;
698 }
699
700 switch (idev->info->mem[mi].memtype) {
701 case UIO_MEM_PHYS:
702 return uio_mmap_physical(vma);
703 case UIO_MEM_LOGICAL:
704 case UIO_MEM_VIRTUAL:
705 return uio_mmap_logical(vma);
706 default:
707 return -EINVAL;
708 }
709}
710
Jan Engelhardt4f014692008-01-22 20:50:54 +0100711static const struct file_operations uio_fops = {
Hans J. Kochbeafc542006-12-07 10:58:29 +0100712 .owner = THIS_MODULE,
713 .open = uio_open,
714 .release = uio_release,
715 .read = uio_read,
Hans J. Koch328a14e2008-05-23 13:50:14 +0200716 .write = uio_write,
Hans J. Kochbeafc542006-12-07 10:58:29 +0100717 .mmap = uio_mmap,
718 .poll = uio_poll,
719 .fasync = uio_fasync,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200720 .llseek = noop_llseek,
Hans J. Kochbeafc542006-12-07 10:58:29 +0100721};
722
723static int uio_major_init(void)
724{
Eric W. Biederman91960a42010-09-14 11:38:06 -0700725 static const char name[] = "uio";
726 struct cdev *cdev = NULL;
727 dev_t uio_dev = 0;
728 int result;
729
730 result = alloc_chrdev_region(&uio_dev, 0, UIO_MAX_DEVICES, name);
731 if (result)
732 goto out;
733
734 result = -ENOMEM;
735 cdev = cdev_alloc();
736 if (!cdev)
737 goto out_unregister;
738
739 cdev->owner = THIS_MODULE;
740 cdev->ops = &uio_fops;
741 kobject_set_name(&cdev->kobj, "%s", name);
742
743 result = cdev_add(cdev, uio_dev, UIO_MAX_DEVICES);
744 if (result)
745 goto out_put;
746
747 uio_major = MAJOR(uio_dev);
748 uio_cdev = cdev;
749 result = 0;
750out:
751 return result;
752out_put:
753 kobject_put(&cdev->kobj);
754out_unregister:
755 unregister_chrdev_region(uio_dev, UIO_MAX_DEVICES);
756 goto out;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100757}
758
759static void uio_major_cleanup(void)
760{
Eric W. Biederman91960a42010-09-14 11:38:06 -0700761 unregister_chrdev_region(MKDEV(uio_major, 0), UIO_MAX_DEVICES);
762 cdev_del(uio_cdev);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100763}
764
765static int init_uio_class(void)
766{
Eric W. Biederman3d4f9d72010-09-14 11:36:27 -0700767 int ret;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100768
769 /* This is the first time in here, set everything up properly */
770 ret = uio_major_init();
771 if (ret)
772 goto exit;
773
Eric W. Biedermanc66fdab2010-09-14 11:38:36 -0700774 ret = class_register(&uio_class);
775 if (ret) {
776 printk(KERN_ERR "class_register failed for uio\n");
777 goto err_class_register;
Hans J. Kochbeafc542006-12-07 10:58:29 +0100778 }
779 return 0;
780
Eric W. Biedermanc66fdab2010-09-14 11:38:36 -0700781err_class_register:
Hans J. Kochbeafc542006-12-07 10:58:29 +0100782 uio_major_cleanup();
783exit:
784 return ret;
785}
786
Eric W. Biederman3d4f9d72010-09-14 11:36:27 -0700787static void release_uio_class(void)
Hans J. Kochbeafc542006-12-07 10:58:29 +0100788{
Eric W. Biedermanc66fdab2010-09-14 11:38:36 -0700789 class_unregister(&uio_class);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100790 uio_major_cleanup();
Hans J. Kochbeafc542006-12-07 10:58:29 +0100791}
792
793/**
794 * uio_register_device - register a new userspace IO device
795 * @owner: module that creates the new device
796 * @parent: parent device
797 * @info: UIO device capabilities
798 *
799 * returns zero on success or a negative error code.
800 */
801int __uio_register_device(struct module *owner,
802 struct device *parent,
803 struct uio_info *info)
804{
805 struct uio_device *idev;
806 int ret = 0;
807
808 if (!parent || !info || !info->name || !info->version)
809 return -EINVAL;
810
811 info->uio_dev = NULL;
812
Hans J. Kochbeafc542006-12-07 10:58:29 +0100813 idev = kzalloc(sizeof(*idev), GFP_KERNEL);
814 if (!idev) {
815 ret = -ENOMEM;
816 goto err_kzalloc;
817 }
818
819 idev->owner = owner;
820 idev->info = info;
821 init_waitqueue_head(&idev->wait);
822 atomic_set(&idev->event, 0);
823
824 ret = uio_get_minor(idev);
825 if (ret)
826 goto err_get_minor;
827
Eric W. Biedermanc66fdab2010-09-14 11:38:36 -0700828 idev->dev = device_create(&uio_class, parent,
Greg Kroah-Hartmana9b12612008-07-21 20:03:34 -0700829 MKDEV(uio_major, idev->minor), idev,
830 "uio%d", idev->minor);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100831 if (IS_ERR(idev->dev)) {
832 printk(KERN_ERR "UIO: device register failed\n");
833 ret = PTR_ERR(idev->dev);
834 goto err_device_create;
835 }
Hans J. Kochbeafc542006-12-07 10:58:29 +0100836
837 ret = uio_dev_add_attributes(idev);
838 if (ret)
839 goto err_uio_dev_add_attributes;
840
841 info->uio_dev = idev;
842
Eric W. Biederman6427a762010-09-14 11:37:36 -0700843 if (info->irq && (info->irq != UIO_IRQ_CUSTOM)) {
844 ret = request_irq(info->irq, uio_interrupt,
845 info->irq_flags, info->name, idev);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100846 if (ret)
847 goto err_request_irq;
848 }
849
850 return 0;
851
852err_request_irq:
853 uio_dev_del_attributes(idev);
854err_uio_dev_add_attributes:
Eric W. Biedermanc66fdab2010-09-14 11:38:36 -0700855 device_destroy(&uio_class, MKDEV(uio_major, idev->minor));
Hans J. Kochbeafc542006-12-07 10:58:29 +0100856err_device_create:
857 uio_free_minor(idev);
858err_get_minor:
859 kfree(idev);
860err_kzalloc:
Hans J. Kochbeafc542006-12-07 10:58:29 +0100861 return ret;
862}
863EXPORT_SYMBOL_GPL(__uio_register_device);
864
865/**
866 * uio_unregister_device - unregister a industrial IO device
867 * @info: UIO device capabilities
868 *
869 */
870void uio_unregister_device(struct uio_info *info)
871{
872 struct uio_device *idev;
873
874 if (!info || !info->uio_dev)
875 return;
876
877 idev = info->uio_dev;
878
879 uio_free_minor(idev);
880
Eric W. Biederman6427a762010-09-14 11:37:36 -0700881 if (info->irq && (info->irq != UIO_IRQ_CUSTOM))
Hans J. Kochbeafc542006-12-07 10:58:29 +0100882 free_irq(info->irq, idev);
883
884 uio_dev_del_attributes(idev);
885
Eric W. Biedermanc66fdab2010-09-14 11:38:36 -0700886 device_destroy(&uio_class, MKDEV(uio_major, idev->minor));
Hans J. Kochbeafc542006-12-07 10:58:29 +0100887 kfree(idev);
Hans J. Kochbeafc542006-12-07 10:58:29 +0100888
889 return;
890}
891EXPORT_SYMBOL_GPL(uio_unregister_device);
892
893static int __init uio_init(void)
894{
Eric W. Biederman3d4f9d72010-09-14 11:36:27 -0700895 return init_uio_class();
Hans J. Kochbeafc542006-12-07 10:58:29 +0100896}
897
898static void __exit uio_exit(void)
899{
Eric W. Biederman3d4f9d72010-09-14 11:36:27 -0700900 release_uio_class();
Hans J. Kochbeafc542006-12-07 10:58:29 +0100901}
902
903module_init(uio_init)
904module_exit(uio_exit)
905MODULE_LICENSE("GPL v2");