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>
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/uio_driver.h>
28 #define UIO_MAX_DEVICES 255
35 struct fasync_struct *async_queue;
36 wait_queue_head_t wait;
38 struct uio_info *info;
39 struct kobject *map_dir;
40 struct kobject *portio_dir;
44 static DEFINE_IDR(uio_idr);
45 static const struct file_operations uio_fops;
47 /* UIO class infrastructure */
48 static struct uio_class {
53 /* Protect idr accesses */
54 static DEFINE_MUTEX(minor_lock);
64 #define to_map(map) container_of(map, struct uio_map, kobj)
66 static ssize_t map_name_show(struct uio_mem *mem, char *buf)
68 if (unlikely(!mem->name))
71 return sprintf(buf, "%s\n", mem->name);
74 static ssize_t map_addr_show(struct uio_mem *mem, char *buf)
76 return sprintf(buf, "0x%lx\n", mem->addr);
79 static ssize_t map_size_show(struct uio_mem *mem, char *buf)
81 return sprintf(buf, "0x%lx\n", mem->size);
84 static ssize_t map_offset_show(struct uio_mem *mem, char *buf)
86 return sprintf(buf, "0x%lx\n", mem->addr & ~PAGE_MASK);
89 struct map_sysfs_entry {
90 struct attribute attr;
91 ssize_t (*show)(struct uio_mem *, char *);
92 ssize_t (*store)(struct uio_mem *, const char *, size_t);
95 static struct map_sysfs_entry name_attribute =
96 __ATTR(name, S_IRUGO, map_name_show, NULL);
97 static struct map_sysfs_entry addr_attribute =
98 __ATTR(addr, S_IRUGO, map_addr_show, NULL);
99 static struct map_sysfs_entry size_attribute =
100 __ATTR(size, S_IRUGO, map_size_show, NULL);
101 static struct map_sysfs_entry offset_attribute =
102 __ATTR(offset, S_IRUGO, map_offset_show, NULL);
104 static struct attribute *attrs[] = {
105 &name_attribute.attr,
106 &addr_attribute.attr,
107 &size_attribute.attr,
108 &offset_attribute.attr,
109 NULL, /* need to NULL terminate the list of attributes */
112 static void map_release(struct kobject *kobj)
114 struct uio_map *map = to_map(kobj);
118 static ssize_t map_type_show(struct kobject *kobj, struct attribute *attr,
121 struct uio_map *map = to_map(kobj);
122 struct uio_mem *mem = map->mem;
123 struct map_sysfs_entry *entry;
125 entry = container_of(attr, struct map_sysfs_entry, attr);
130 return entry->show(mem, buf);
133 static const struct sysfs_ops map_sysfs_ops = {
134 .show = map_type_show,
137 static struct kobj_type map_attr_type = {
138 .release = map_release,
139 .sysfs_ops = &map_sysfs_ops,
140 .default_attrs = attrs,
145 struct uio_port *port;
147 #define to_portio(portio) container_of(portio, struct uio_portio, kobj)
149 static ssize_t portio_name_show(struct uio_port *port, char *buf)
151 if (unlikely(!port->name))
154 return sprintf(buf, "%s\n", port->name);
157 static ssize_t portio_start_show(struct uio_port *port, char *buf)
159 return sprintf(buf, "0x%lx\n", port->start);
162 static ssize_t portio_size_show(struct uio_port *port, char *buf)
164 return sprintf(buf, "0x%lx\n", port->size);
167 static ssize_t portio_porttype_show(struct uio_port *port, char *buf)
169 const char *porttypes[] = {"none", "x86", "gpio", "other"};
171 if ((port->porttype < 0) || (port->porttype > UIO_PORT_OTHER))
174 return sprintf(buf, "port_%s\n", porttypes[port->porttype]);
177 struct portio_sysfs_entry {
178 struct attribute attr;
179 ssize_t (*show)(struct uio_port *, char *);
180 ssize_t (*store)(struct uio_port *, const char *, size_t);
183 static struct portio_sysfs_entry portio_name_attribute =
184 __ATTR(name, S_IRUGO, portio_name_show, NULL);
185 static struct portio_sysfs_entry portio_start_attribute =
186 __ATTR(start, S_IRUGO, portio_start_show, NULL);
187 static struct portio_sysfs_entry portio_size_attribute =
188 __ATTR(size, S_IRUGO, portio_size_show, NULL);
189 static struct portio_sysfs_entry portio_porttype_attribute =
190 __ATTR(porttype, S_IRUGO, portio_porttype_show, NULL);
192 static struct attribute *portio_attrs[] = {
193 &portio_name_attribute.attr,
194 &portio_start_attribute.attr,
195 &portio_size_attribute.attr,
196 &portio_porttype_attribute.attr,
200 static void portio_release(struct kobject *kobj)
202 struct uio_portio *portio = to_portio(kobj);
206 static ssize_t portio_type_show(struct kobject *kobj, struct attribute *attr,
209 struct uio_portio *portio = to_portio(kobj);
210 struct uio_port *port = portio->port;
211 struct portio_sysfs_entry *entry;
213 entry = container_of(attr, struct portio_sysfs_entry, attr);
218 return entry->show(port, buf);
221 static const struct sysfs_ops portio_sysfs_ops = {
222 .show = portio_type_show,
225 static struct kobj_type portio_attr_type = {
226 .release = portio_release,
227 .sysfs_ops = &portio_sysfs_ops,
228 .default_attrs = portio_attrs,
231 static ssize_t show_name(struct device *dev,
232 struct device_attribute *attr, char *buf)
234 struct uio_device *idev = dev_get_drvdata(dev);
236 return sprintf(buf, "%s\n", idev->info->name);
240 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
242 static ssize_t show_version(struct device *dev,
243 struct device_attribute *attr, char *buf)
245 struct uio_device *idev = dev_get_drvdata(dev);
247 return sprintf(buf, "%s\n", idev->info->version);
251 static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
253 static ssize_t show_event(struct device *dev,
254 struct device_attribute *attr, char *buf)
256 struct uio_device *idev = dev_get_drvdata(dev);
258 return sprintf(buf, "%u\n",
259 (unsigned int)atomic_read(&idev->event));
263 static DEVICE_ATTR(event, S_IRUGO, show_event, NULL);
265 static struct attribute *uio_attrs[] = {
267 &dev_attr_version.attr,
268 &dev_attr_event.attr,
272 static struct attribute_group uio_attr_grp = {
279 static int uio_dev_add_attributes(struct uio_device *idev)
284 int portio_found = 0;
287 struct uio_port *port;
288 struct uio_portio *portio;
290 ret = sysfs_create_group(&idev->dev->kobj, &uio_attr_grp);
294 for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
295 mem = &idev->info->mem[mi];
300 idev->map_dir = kobject_create_and_add("maps",
305 map = kzalloc(sizeof(*map), GFP_KERNEL);
308 kobject_init(&map->kobj, &map_attr_type);
311 ret = kobject_add(&map->kobj, idev->map_dir, "map%d", mi);
314 ret = kobject_uevent(&map->kobj, KOBJ_ADD);
319 for (pi = 0; pi < MAX_UIO_PORT_REGIONS; pi++) {
320 port = &idev->info->port[pi];
325 idev->portio_dir = kobject_create_and_add("portio",
327 if (!idev->portio_dir)
330 portio = kzalloc(sizeof(*portio), GFP_KERNEL);
333 kobject_init(&portio->kobj, &portio_attr_type);
335 port->portio = portio;
336 ret = kobject_add(&portio->kobj, idev->portio_dir,
340 ret = kobject_uevent(&portio->kobj, KOBJ_ADD);
348 for (pi--; pi >= 0; pi--) {
349 port = &idev->info->port[pi];
350 portio = port->portio;
351 kobject_put(&portio->kobj);
353 kobject_put(idev->portio_dir);
355 for (mi--; mi>=0; mi--) {
356 mem = &idev->info->mem[mi];
358 kobject_put(&map->kobj);
360 kobject_put(idev->map_dir);
361 sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp);
363 dev_err(idev->dev, "error creating sysfs files (%d)\n", ret);
367 static void uio_dev_del_attributes(struct uio_device *idev)
371 struct uio_port *port;
373 for (i = 0; i < MAX_UIO_MAPS; i++) {
374 mem = &idev->info->mem[i];
377 kobject_put(&mem->map->kobj);
379 kobject_put(idev->map_dir);
381 for (i = 0; i < MAX_UIO_PORT_REGIONS; i++) {
382 port = &idev->info->port[i];
385 kobject_put(&port->portio->kobj);
387 kobject_put(idev->portio_dir);
389 sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp);
392 static int uio_get_minor(struct uio_device *idev)
394 int retval = -ENOMEM;
397 mutex_lock(&minor_lock);
398 if (idr_pre_get(&uio_idr, GFP_KERNEL) == 0)
401 retval = idr_get_new(&uio_idr, idev, &id);
403 if (retval == -EAGAIN)
407 idev->minor = id & MAX_ID_MASK;
409 mutex_unlock(&minor_lock);
413 static void uio_free_minor(struct uio_device *idev)
415 mutex_lock(&minor_lock);
416 idr_remove(&uio_idr, idev->minor);
417 mutex_unlock(&minor_lock);
421 * uio_event_notify - trigger an interrupt event
422 * @info: UIO device capabilities
424 void uio_event_notify(struct uio_info *info)
426 struct uio_device *idev = info->uio_dev;
428 atomic_inc(&idev->event);
429 wake_up_interruptible(&idev->wait);
430 kill_fasync(&idev->async_queue, SIGIO, POLL_IN);
432 EXPORT_SYMBOL_GPL(uio_event_notify);
435 * uio_interrupt - hardware interrupt handler
436 * @irq: IRQ number, can be UIO_IRQ_CYCLIC for cyclic timer
437 * @dev_id: Pointer to the devices uio_device structure
439 static irqreturn_t uio_interrupt(int irq, void *dev_id)
441 struct uio_device *idev = (struct uio_device *)dev_id;
442 irqreturn_t ret = idev->info->handler(irq, idev->info);
444 if (ret == IRQ_HANDLED)
445 uio_event_notify(idev->info);
450 struct uio_listener {
451 struct uio_device *dev;
455 static int uio_open(struct inode *inode, struct file *filep)
457 struct uio_device *idev;
458 struct uio_listener *listener;
461 mutex_lock(&minor_lock);
462 idev = idr_find(&uio_idr, iminor(inode));
463 mutex_unlock(&minor_lock);
469 if (!try_module_get(idev->owner)) {
474 listener = kmalloc(sizeof(*listener), GFP_KERNEL);
477 goto err_alloc_listener;
480 listener->dev = idev;
481 listener->event_count = atomic_read(&idev->event);
482 filep->private_data = listener;
484 if (idev->info->open) {
485 ret = idev->info->open(idev->info, inode);
495 module_put(idev->owner);
501 static int uio_fasync(int fd, struct file *filep, int on)
503 struct uio_listener *listener = filep->private_data;
504 struct uio_device *idev = listener->dev;
506 return fasync_helper(fd, filep, on, &idev->async_queue);
509 static int uio_release(struct inode *inode, struct file *filep)
512 struct uio_listener *listener = filep->private_data;
513 struct uio_device *idev = listener->dev;
515 if (idev->info->release)
516 ret = idev->info->release(idev->info, inode);
518 module_put(idev->owner);
523 static unsigned int uio_poll(struct file *filep, poll_table *wait)
525 struct uio_listener *listener = filep->private_data;
526 struct uio_device *idev = listener->dev;
528 if (idev->info->irq == UIO_IRQ_NONE)
531 poll_wait(filep, &idev->wait, wait);
532 if (listener->event_count != atomic_read(&idev->event))
533 return POLLIN | POLLRDNORM;
537 static ssize_t uio_read(struct file *filep, char __user *buf,
538 size_t count, loff_t *ppos)
540 struct uio_listener *listener = filep->private_data;
541 struct uio_device *idev = listener->dev;
542 DECLARE_WAITQUEUE(wait, current);
546 if (idev->info->irq == UIO_IRQ_NONE)
549 if (count != sizeof(s32))
552 add_wait_queue(&idev->wait, &wait);
555 set_current_state(TASK_INTERRUPTIBLE);
557 event_count = atomic_read(&idev->event);
558 if (event_count != listener->event_count) {
559 if (copy_to_user(buf, &event_count, count))
562 listener->event_count = event_count;
568 if (filep->f_flags & O_NONBLOCK) {
573 if (signal_pending(current)) {
574 retval = -ERESTARTSYS;
580 __set_current_state(TASK_RUNNING);
581 remove_wait_queue(&idev->wait, &wait);
586 static ssize_t uio_write(struct file *filep, const char __user *buf,
587 size_t count, loff_t *ppos)
589 struct uio_listener *listener = filep->private_data;
590 struct uio_device *idev = listener->dev;
594 if (idev->info->irq == UIO_IRQ_NONE)
597 if (count != sizeof(s32))
600 if (!idev->info->irqcontrol)
603 if (copy_from_user(&irq_on, buf, count))
606 retval = idev->info->irqcontrol(idev->info, irq_on);
608 return retval ? retval : sizeof(s32);
611 static int uio_find_mem_index(struct vm_area_struct *vma)
614 struct uio_device *idev = vma->vm_private_data;
616 for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
617 if (idev->info->mem[mi].size == 0)
619 if (vma->vm_pgoff == mi)
625 static void uio_vma_open(struct vm_area_struct *vma)
627 struct uio_device *idev = vma->vm_private_data;
631 static void uio_vma_close(struct vm_area_struct *vma)
633 struct uio_device *idev = vma->vm_private_data;
637 static int uio_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
639 struct uio_device *idev = vma->vm_private_data;
641 unsigned long offset;
643 int mi = uio_find_mem_index(vma);
645 return VM_FAULT_SIGBUS;
648 * We need to subtract mi because userspace uses offset = N*PAGE_SIZE
651 offset = (vmf->pgoff - mi) << PAGE_SHIFT;
653 if (idev->info->mem[mi].memtype == UIO_MEM_LOGICAL)
654 page = virt_to_page(idev->info->mem[mi].addr + offset);
656 page = vmalloc_to_page((void *)idev->info->mem[mi].addr
663 static const struct vm_operations_struct uio_vm_ops = {
664 .open = uio_vma_open,
665 .close = uio_vma_close,
666 .fault = uio_vma_fault,
669 static int uio_mmap_physical(struct vm_area_struct *vma)
671 struct uio_device *idev = vma->vm_private_data;
672 int mi = uio_find_mem_index(vma);
676 vma->vm_flags |= VM_IO | VM_RESERVED;
678 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
680 return remap_pfn_range(vma,
682 idev->info->mem[mi].addr >> PAGE_SHIFT,
683 vma->vm_end - vma->vm_start,
687 static int uio_mmap_logical(struct vm_area_struct *vma)
689 vma->vm_flags |= VM_RESERVED;
690 vma->vm_ops = &uio_vm_ops;
695 static int uio_mmap(struct file *filep, struct vm_area_struct *vma)
697 struct uio_listener *listener = filep->private_data;
698 struct uio_device *idev = listener->dev;
700 unsigned long requested_pages, actual_pages;
703 if (vma->vm_end < vma->vm_start)
706 vma->vm_private_data = idev;
708 mi = uio_find_mem_index(vma);
712 requested_pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
713 actual_pages = ((idev->info->mem[mi].addr & ~PAGE_MASK)
714 + idev->info->mem[mi].size + PAGE_SIZE -1) >> PAGE_SHIFT;
715 if (requested_pages > actual_pages)
718 if (idev->info->mmap) {
719 ret = idev->info->mmap(idev->info, vma);
723 switch (idev->info->mem[mi].memtype) {
725 return uio_mmap_physical(vma);
726 case UIO_MEM_LOGICAL:
727 case UIO_MEM_VIRTUAL:
728 return uio_mmap_logical(vma);
734 static const struct file_operations uio_fops = {
735 .owner = THIS_MODULE,
737 .release = uio_release,
742 .fasync = uio_fasync,
745 static int uio_major_init(void)
747 uio_major = register_chrdev(0, "uio", &uio_fops);
753 static void uio_major_cleanup(void)
755 unregister_chrdev(uio_major, "uio");
758 static int init_uio_class(void)
762 if (uio_class != NULL) {
763 kref_get(&uio_class->kref);
767 /* This is the first time in here, set everything up properly */
768 ret = uio_major_init();
772 uio_class = kzalloc(sizeof(*uio_class), GFP_KERNEL);
778 kref_init(&uio_class->kref);
779 uio_class->class = class_create(THIS_MODULE, "uio");
780 if (IS_ERR(uio_class->class)) {
781 ret = IS_ERR(uio_class->class);
782 printk(KERN_ERR "class_create failed for uio\n");
783 goto err_class_create;
796 static void release_uio_class(struct kref *kref)
798 /* Ok, we cheat as we know we only have one uio_class */
799 class_destroy(uio_class->class);
805 static void uio_class_destroy(void)
808 kref_put(&uio_class->kref, release_uio_class);
812 * uio_register_device - register a new userspace IO device
813 * @owner: module that creates the new device
814 * @parent: parent device
815 * @info: UIO device capabilities
817 * returns zero on success or a negative error code.
819 int __uio_register_device(struct module *owner,
820 struct device *parent,
821 struct uio_info *info)
823 struct uio_device *idev;
826 if (!parent || !info || !info->name || !info->version)
829 info->uio_dev = NULL;
831 ret = init_uio_class();
835 idev = kzalloc(sizeof(*idev), GFP_KERNEL);
843 init_waitqueue_head(&idev->wait);
844 atomic_set(&idev->event, 0);
846 ret = uio_get_minor(idev);
850 idev->dev = device_create(uio_class->class, parent,
851 MKDEV(uio_major, idev->minor), idev,
852 "uio%d", idev->minor);
853 if (IS_ERR(idev->dev)) {
854 printk(KERN_ERR "UIO: device register failed\n");
855 ret = PTR_ERR(idev->dev);
856 goto err_device_create;
859 ret = uio_dev_add_attributes(idev);
861 goto err_uio_dev_add_attributes;
863 info->uio_dev = idev;
865 if (idev->info->irq >= 0) {
866 ret = request_irq(idev->info->irq, uio_interrupt,
867 idev->info->irq_flags, idev->info->name, idev);
869 goto err_request_irq;
875 uio_dev_del_attributes(idev);
876 err_uio_dev_add_attributes:
877 device_destroy(uio_class->class, MKDEV(uio_major, idev->minor));
879 uio_free_minor(idev);
886 EXPORT_SYMBOL_GPL(__uio_register_device);
889 * uio_unregister_device - unregister a industrial IO device
890 * @info: UIO device capabilities
893 void uio_unregister_device(struct uio_info *info)
895 struct uio_device *idev;
897 if (!info || !info->uio_dev)
900 idev = info->uio_dev;
902 uio_free_minor(idev);
905 free_irq(info->irq, idev);
907 uio_dev_del_attributes(idev);
909 dev_set_drvdata(idev->dev, NULL);
910 device_destroy(uio_class->class, MKDEV(uio_major, idev->minor));
916 EXPORT_SYMBOL_GPL(uio_unregister_device);
918 static int __init uio_init(void)
923 static void __exit uio_exit(void)
927 module_init(uio_init)
928 module_exit(uio_exit)
929 MODULE_LICENSE("GPL v2");