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@hansjkoch.de>
7 * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com>
13 * Licensed under the GPLv2 only.
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/poll.h>
19 #include <linux/device.h>
20 #include <linux/slab.h>
22 #include <linux/idr.h>
23 #include <linux/sched.h>
24 #include <linux/string.h>
25 #include <linux/kobject.h>
26 #include <linux/cdev.h>
27 #include <linux/uio_driver.h>
29 #define UIO_MAX_DEVICES (1U << MINORBITS)
36 struct fasync_struct *async_queue;
37 wait_queue_head_t wait;
38 struct uio_info *info;
39 struct kobject *map_dir;
40 struct kobject *portio_dir;
44 static struct cdev *uio_cdev;
45 static DEFINE_IDR(uio_idr);
46 static const struct file_operations uio_fops;
48 /* Protect idr accesses */
49 static DEFINE_MUTEX(minor_lock);
59 #define to_map(map) container_of(map, struct uio_map, kobj)
61 static ssize_t map_name_show(struct uio_mem *mem, char *buf)
63 if (unlikely(!mem->name))
66 return sprintf(buf, "%s\n", mem->name);
69 static ssize_t map_addr_show(struct uio_mem *mem, char *buf)
71 return sprintf(buf, "0x%llx\n", (unsigned long long)mem->addr);
74 static ssize_t map_size_show(struct uio_mem *mem, char *buf)
76 return sprintf(buf, "0x%lx\n", mem->size);
79 static ssize_t map_offset_show(struct uio_mem *mem, char *buf)
81 return sprintf(buf, "0x%llx\n", (unsigned long long)mem->addr & ~PAGE_MASK);
84 struct map_sysfs_entry {
85 struct attribute attr;
86 ssize_t (*show)(struct uio_mem *, char *);
87 ssize_t (*store)(struct uio_mem *, const char *, size_t);
90 static struct map_sysfs_entry name_attribute =
91 __ATTR(name, S_IRUGO, map_name_show, NULL);
92 static struct map_sysfs_entry addr_attribute =
93 __ATTR(addr, S_IRUGO, map_addr_show, NULL);
94 static struct map_sysfs_entry size_attribute =
95 __ATTR(size, S_IRUGO, map_size_show, NULL);
96 static struct map_sysfs_entry offset_attribute =
97 __ATTR(offset, S_IRUGO, map_offset_show, NULL);
99 static struct attribute *attrs[] = {
100 &name_attribute.attr,
101 &addr_attribute.attr,
102 &size_attribute.attr,
103 &offset_attribute.attr,
104 NULL, /* need to NULL terminate the list of attributes */
107 static void map_release(struct kobject *kobj)
109 struct uio_map *map = to_map(kobj);
113 static ssize_t map_type_show(struct kobject *kobj, struct attribute *attr,
116 struct uio_map *map = to_map(kobj);
117 struct uio_mem *mem = map->mem;
118 struct map_sysfs_entry *entry;
120 entry = container_of(attr, struct map_sysfs_entry, attr);
125 return entry->show(mem, buf);
128 static const struct sysfs_ops map_sysfs_ops = {
129 .show = map_type_show,
132 static struct kobj_type map_attr_type = {
133 .release = map_release,
134 .sysfs_ops = &map_sysfs_ops,
135 .default_attrs = attrs,
140 struct uio_port *port;
142 #define to_portio(portio) container_of(portio, struct uio_portio, kobj)
144 static ssize_t portio_name_show(struct uio_port *port, char *buf)
146 if (unlikely(!port->name))
149 return sprintf(buf, "%s\n", port->name);
152 static ssize_t portio_start_show(struct uio_port *port, char *buf)
154 return sprintf(buf, "0x%lx\n", port->start);
157 static ssize_t portio_size_show(struct uio_port *port, char *buf)
159 return sprintf(buf, "0x%lx\n", port->size);
162 static ssize_t portio_porttype_show(struct uio_port *port, char *buf)
164 const char *porttypes[] = {"none", "x86", "gpio", "other"};
166 if ((port->porttype < 0) || (port->porttype > UIO_PORT_OTHER))
169 return sprintf(buf, "port_%s\n", porttypes[port->porttype]);
172 struct portio_sysfs_entry {
173 struct attribute attr;
174 ssize_t (*show)(struct uio_port *, char *);
175 ssize_t (*store)(struct uio_port *, const char *, size_t);
178 static struct portio_sysfs_entry portio_name_attribute =
179 __ATTR(name, S_IRUGO, portio_name_show, NULL);
180 static struct portio_sysfs_entry portio_start_attribute =
181 __ATTR(start, S_IRUGO, portio_start_show, NULL);
182 static struct portio_sysfs_entry portio_size_attribute =
183 __ATTR(size, S_IRUGO, portio_size_show, NULL);
184 static struct portio_sysfs_entry portio_porttype_attribute =
185 __ATTR(porttype, S_IRUGO, portio_porttype_show, NULL);
187 static struct attribute *portio_attrs[] = {
188 &portio_name_attribute.attr,
189 &portio_start_attribute.attr,
190 &portio_size_attribute.attr,
191 &portio_porttype_attribute.attr,
195 static void portio_release(struct kobject *kobj)
197 struct uio_portio *portio = to_portio(kobj);
201 static ssize_t portio_type_show(struct kobject *kobj, struct attribute *attr,
204 struct uio_portio *portio = to_portio(kobj);
205 struct uio_port *port = portio->port;
206 struct portio_sysfs_entry *entry;
208 entry = container_of(attr, struct portio_sysfs_entry, attr);
213 return entry->show(port, buf);
216 static const struct sysfs_ops portio_sysfs_ops = {
217 .show = portio_type_show,
220 static struct kobj_type portio_attr_type = {
221 .release = portio_release,
222 .sysfs_ops = &portio_sysfs_ops,
223 .default_attrs = portio_attrs,
226 static ssize_t name_show(struct device *dev,
227 struct device_attribute *attr, char *buf)
229 struct uio_device *idev = dev_get_drvdata(dev);
230 return sprintf(buf, "%s\n", idev->info->name);
232 static DEVICE_ATTR_RO(name);
234 static ssize_t version_show(struct device *dev,
235 struct device_attribute *attr, char *buf)
237 struct uio_device *idev = dev_get_drvdata(dev);
238 return sprintf(buf, "%s\n", idev->info->version);
240 static DEVICE_ATTR_RO(version);
242 static ssize_t event_show(struct device *dev,
243 struct device_attribute *attr, char *buf)
245 struct uio_device *idev = dev_get_drvdata(dev);
246 return sprintf(buf, "%u\n", (unsigned int)atomic_read(&idev->event));
248 static DEVICE_ATTR_RO(event);
250 static struct attribute *uio_attrs[] = {
252 &dev_attr_version.attr,
253 &dev_attr_event.attr,
256 ATTRIBUTE_GROUPS(uio);
258 /* UIO class infrastructure */
259 static struct class uio_class = {
261 .dev_groups = uio_groups,
267 static int uio_dev_add_attributes(struct uio_device *idev)
272 int portio_found = 0;
275 struct uio_port *port;
276 struct uio_portio *portio;
278 for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
279 mem = &idev->info->mem[mi];
284 idev->map_dir = kobject_create_and_add("maps",
289 map = kzalloc(sizeof(*map), GFP_KERNEL);
292 kobject_init(&map->kobj, &map_attr_type);
295 ret = kobject_add(&map->kobj, idev->map_dir, "map%d", mi);
298 ret = kobject_uevent(&map->kobj, KOBJ_ADD);
303 for (pi = 0; pi < MAX_UIO_PORT_REGIONS; pi++) {
304 port = &idev->info->port[pi];
309 idev->portio_dir = kobject_create_and_add("portio",
311 if (!idev->portio_dir)
314 portio = kzalloc(sizeof(*portio), GFP_KERNEL);
316 goto err_portio_kobj;
317 kobject_init(&portio->kobj, &portio_attr_type);
319 port->portio = portio;
320 ret = kobject_add(&portio->kobj, idev->portio_dir,
323 goto err_portio_kobj;
324 ret = kobject_uevent(&portio->kobj, KOBJ_ADD);
334 for (; pi >= 0; pi--) {
335 port = &idev->info->port[pi];
336 portio = port->portio;
337 kobject_put(&portio->kobj);
339 kobject_put(idev->portio_dir);
343 for (; mi >= 0; mi--) {
344 mem = &idev->info->mem[mi];
346 kobject_put(&map->kobj);
348 kobject_put(idev->map_dir);
349 dev_err(idev->dev, "error creating sysfs files (%d)\n", ret);
353 static void uio_dev_del_attributes(struct uio_device *idev)
357 struct uio_port *port;
359 for (i = 0; i < MAX_UIO_MAPS; i++) {
360 mem = &idev->info->mem[i];
363 kobject_put(&mem->map->kobj);
365 kobject_put(idev->map_dir);
367 for (i = 0; i < MAX_UIO_PORT_REGIONS; i++) {
368 port = &idev->info->port[i];
371 kobject_put(&port->portio->kobj);
373 kobject_put(idev->portio_dir);
376 static int uio_get_minor(struct uio_device *idev)
378 int retval = -ENOMEM;
380 mutex_lock(&minor_lock);
381 retval = idr_alloc(&uio_idr, idev, 0, UIO_MAX_DEVICES, GFP_KERNEL);
383 idev->minor = retval;
385 } else if (retval == -ENOSPC) {
386 dev_err(idev->dev, "too many uio devices\n");
389 mutex_unlock(&minor_lock);
393 static void uio_free_minor(struct uio_device *idev)
395 mutex_lock(&minor_lock);
396 idr_remove(&uio_idr, idev->minor);
397 mutex_unlock(&minor_lock);
401 * uio_event_notify - trigger an interrupt event
402 * @info: UIO device capabilities
404 void uio_event_notify(struct uio_info *info)
406 struct uio_device *idev = info->uio_dev;
408 atomic_inc(&idev->event);
409 wake_up_interruptible(&idev->wait);
410 kill_fasync(&idev->async_queue, SIGIO, POLL_IN);
412 EXPORT_SYMBOL_GPL(uio_event_notify);
415 * uio_interrupt - hardware interrupt handler
416 * @irq: IRQ number, can be UIO_IRQ_CYCLIC for cyclic timer
417 * @dev_id: Pointer to the devices uio_device structure
419 static irqreturn_t uio_interrupt(int irq, void *dev_id)
421 struct uio_device *idev = (struct uio_device *)dev_id;
422 irqreturn_t ret = idev->info->handler(irq, idev->info);
424 if (ret == IRQ_HANDLED)
425 uio_event_notify(idev->info);
430 struct uio_listener {
431 struct uio_device *dev;
435 static int uio_open(struct inode *inode, struct file *filep)
437 struct uio_device *idev;
438 struct uio_listener *listener;
441 mutex_lock(&minor_lock);
442 idev = idr_find(&uio_idr, iminor(inode));
443 mutex_unlock(&minor_lock);
449 if (!try_module_get(idev->owner)) {
454 listener = kmalloc(sizeof(*listener), GFP_KERNEL);
457 goto err_alloc_listener;
460 listener->dev = idev;
461 listener->event_count = atomic_read(&idev->event);
462 filep->private_data = listener;
464 if (idev->info->open) {
465 ret = idev->info->open(idev->info, inode);
475 module_put(idev->owner);
481 static int uio_fasync(int fd, struct file *filep, int on)
483 struct uio_listener *listener = filep->private_data;
484 struct uio_device *idev = listener->dev;
486 return fasync_helper(fd, filep, on, &idev->async_queue);
489 static int uio_release(struct inode *inode, struct file *filep)
492 struct uio_listener *listener = filep->private_data;
493 struct uio_device *idev = listener->dev;
495 if (idev->info->release)
496 ret = idev->info->release(idev->info, inode);
498 module_put(idev->owner);
503 static unsigned int uio_poll(struct file *filep, poll_table *wait)
505 struct uio_listener *listener = filep->private_data;
506 struct uio_device *idev = listener->dev;
508 if (!idev->info->irq)
511 poll_wait(filep, &idev->wait, wait);
512 if (listener->event_count != atomic_read(&idev->event))
513 return POLLIN | POLLRDNORM;
517 static ssize_t uio_read(struct file *filep, char __user *buf,
518 size_t count, loff_t *ppos)
520 struct uio_listener *listener = filep->private_data;
521 struct uio_device *idev = listener->dev;
522 DECLARE_WAITQUEUE(wait, current);
526 if (!idev->info->irq)
529 if (count != sizeof(s32))
532 add_wait_queue(&idev->wait, &wait);
535 set_current_state(TASK_INTERRUPTIBLE);
537 event_count = atomic_read(&idev->event);
538 if (event_count != listener->event_count) {
539 if (copy_to_user(buf, &event_count, count))
542 listener->event_count = event_count;
548 if (filep->f_flags & O_NONBLOCK) {
553 if (signal_pending(current)) {
554 retval = -ERESTARTSYS;
560 __set_current_state(TASK_RUNNING);
561 remove_wait_queue(&idev->wait, &wait);
566 static ssize_t uio_write(struct file *filep, const char __user *buf,
567 size_t count, loff_t *ppos)
569 struct uio_listener *listener = filep->private_data;
570 struct uio_device *idev = listener->dev;
574 if (!idev->info->irq)
577 if (count != sizeof(s32))
580 if (!idev->info->irqcontrol)
583 if (copy_from_user(&irq_on, buf, count))
586 retval = idev->info->irqcontrol(idev->info, irq_on);
588 return retval ? retval : sizeof(s32);
591 static int uio_find_mem_index(struct vm_area_struct *vma)
593 struct uio_device *idev = vma->vm_private_data;
595 if (vma->vm_pgoff < MAX_UIO_MAPS) {
596 if (idev->info->mem[vma->vm_pgoff].size == 0)
598 return (int)vma->vm_pgoff;
603 static int uio_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
605 struct uio_device *idev = vma->vm_private_data;
607 unsigned long offset;
609 int mi = uio_find_mem_index(vma);
611 return VM_FAULT_SIGBUS;
614 * We need to subtract mi because userspace uses offset = N*PAGE_SIZE
617 offset = (vmf->pgoff - mi) << PAGE_SHIFT;
619 if (idev->info->mem[mi].memtype == UIO_MEM_LOGICAL)
620 page = virt_to_page(idev->info->mem[mi].addr + offset);
622 page = vmalloc_to_page((void *)(unsigned long)idev->info->mem[mi].addr + offset);
628 static const struct vm_operations_struct uio_logical_vm_ops = {
629 .fault = uio_vma_fault,
632 static int uio_mmap_logical(struct vm_area_struct *vma)
634 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
635 vma->vm_ops = &uio_logical_vm_ops;
639 static const struct vm_operations_struct uio_physical_vm_ops = {
640 #ifdef CONFIG_HAVE_IOREMAP_PROT
641 .access = generic_access_phys,
645 static int uio_mmap_physical(struct vm_area_struct *vma)
647 struct uio_device *idev = vma->vm_private_data;
648 int mi = uio_find_mem_index(vma);
652 vma->vm_ops = &uio_physical_vm_ops;
654 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
656 return remap_pfn_range(vma,
658 idev->info->mem[mi].addr >> PAGE_SHIFT,
659 vma->vm_end - vma->vm_start,
663 static int uio_mmap(struct file *filep, struct vm_area_struct *vma)
665 struct uio_listener *listener = filep->private_data;
666 struct uio_device *idev = listener->dev;
668 unsigned long requested_pages, actual_pages;
671 if (vma->vm_end < vma->vm_start)
674 vma->vm_private_data = idev;
676 mi = uio_find_mem_index(vma);
680 requested_pages = vma_pages(vma);
681 actual_pages = ((idev->info->mem[mi].addr & ~PAGE_MASK)
682 + idev->info->mem[mi].size + PAGE_SIZE -1) >> PAGE_SHIFT;
683 if (requested_pages > actual_pages)
686 if (idev->info->mmap) {
687 ret = idev->info->mmap(idev->info, vma);
691 switch (idev->info->mem[mi].memtype) {
693 return uio_mmap_physical(vma);
694 case UIO_MEM_LOGICAL:
695 case UIO_MEM_VIRTUAL:
696 return uio_mmap_logical(vma);
702 static const struct file_operations uio_fops = {
703 .owner = THIS_MODULE,
705 .release = uio_release,
710 .fasync = uio_fasync,
711 .llseek = noop_llseek,
714 static int uio_major_init(void)
716 static const char name[] = "uio";
717 struct cdev *cdev = NULL;
721 result = alloc_chrdev_region(&uio_dev, 0, UIO_MAX_DEVICES, name);
730 cdev->owner = THIS_MODULE;
731 cdev->ops = &uio_fops;
732 kobject_set_name(&cdev->kobj, "%s", name);
734 result = cdev_add(cdev, uio_dev, UIO_MAX_DEVICES);
738 uio_major = MAJOR(uio_dev);
742 kobject_put(&cdev->kobj);
744 unregister_chrdev_region(uio_dev, UIO_MAX_DEVICES);
749 static void uio_major_cleanup(void)
751 unregister_chrdev_region(MKDEV(uio_major, 0), UIO_MAX_DEVICES);
755 static int init_uio_class(void)
759 /* This is the first time in here, set everything up properly */
760 ret = uio_major_init();
764 ret = class_register(&uio_class);
766 printk(KERN_ERR "class_register failed for uio\n");
767 goto err_class_register;
777 static void release_uio_class(void)
779 class_unregister(&uio_class);
784 * uio_register_device - register a new userspace IO device
785 * @owner: module that creates the new device
786 * @parent: parent device
787 * @info: UIO device capabilities
789 * returns zero on success or a negative error code.
791 int __uio_register_device(struct module *owner,
792 struct device *parent,
793 struct uio_info *info)
795 struct uio_device *idev;
798 if (!parent || !info || !info->name || !info->version)
801 info->uio_dev = NULL;
803 idev = devm_kzalloc(parent, sizeof(*idev), GFP_KERNEL);
810 init_waitqueue_head(&idev->wait);
811 atomic_set(&idev->event, 0);
813 ret = uio_get_minor(idev);
817 idev->dev = device_create(&uio_class, parent,
818 MKDEV(uio_major, idev->minor), idev,
819 "uio%d", idev->minor);
820 if (IS_ERR(idev->dev)) {
821 printk(KERN_ERR "UIO: device register failed\n");
822 ret = PTR_ERR(idev->dev);
823 goto err_device_create;
826 ret = uio_dev_add_attributes(idev);
828 goto err_uio_dev_add_attributes;
830 info->uio_dev = idev;
832 if (info->irq && (info->irq != UIO_IRQ_CUSTOM)) {
833 ret = devm_request_irq(parent, info->irq, uio_interrupt,
834 info->irq_flags, info->name, idev);
836 goto err_request_irq;
842 uio_dev_del_attributes(idev);
843 err_uio_dev_add_attributes:
844 device_destroy(&uio_class, MKDEV(uio_major, idev->minor));
846 uio_free_minor(idev);
849 EXPORT_SYMBOL_GPL(__uio_register_device);
852 * uio_unregister_device - unregister a industrial IO device
853 * @info: UIO device capabilities
856 void uio_unregister_device(struct uio_info *info)
858 struct uio_device *idev;
860 if (!info || !info->uio_dev)
863 idev = info->uio_dev;
865 uio_free_minor(idev);
867 uio_dev_del_attributes(idev);
869 device_destroy(&uio_class, MKDEV(uio_major, idev->minor));
873 EXPORT_SYMBOL_GPL(uio_unregister_device);
875 static int __init uio_init(void)
877 return init_uio_class();
880 static void __exit uio_exit(void)
885 module_init(uio_init)
886 module_exit(uio_exit)
887 MODULE_LICENSE("GPL v2");