1beafc54cSHans J. Koch /* 2beafc54cSHans J. Koch * drivers/uio/uio.c 3beafc54cSHans J. Koch * 4beafc54cSHans J. Koch * Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de> 5beafc54cSHans J. Koch * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de> 6beafc54cSHans J. Koch * Copyright(C) 2006, Hans J. Koch <hjk@linutronix.de> 7beafc54cSHans J. Koch * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com> 8beafc54cSHans J. Koch * 9beafc54cSHans J. Koch * Userspace IO 10beafc54cSHans J. Koch * 11beafc54cSHans J. Koch * Base Functions 12beafc54cSHans J. Koch * 13beafc54cSHans J. Koch * Licensed under the GPLv2 only. 14beafc54cSHans J. Koch */ 15beafc54cSHans J. Koch 16beafc54cSHans J. Koch #include <linux/module.h> 17beafc54cSHans J. Koch #include <linux/init.h> 18beafc54cSHans J. Koch #include <linux/poll.h> 19beafc54cSHans J. Koch #include <linux/device.h> 20beafc54cSHans J. Koch #include <linux/mm.h> 21beafc54cSHans J. Koch #include <linux/idr.h> 22beafc54cSHans J. Koch #include <linux/string.h> 23beafc54cSHans J. Koch #include <linux/kobject.h> 24beafc54cSHans J. Koch #include <linux/uio_driver.h> 25beafc54cSHans J. Koch 26beafc54cSHans J. Koch #define UIO_MAX_DEVICES 255 27beafc54cSHans J. Koch 28beafc54cSHans J. Koch struct uio_device { 29beafc54cSHans J. Koch struct module *owner; 30beafc54cSHans J. Koch struct device *dev; 31beafc54cSHans J. Koch int minor; 32beafc54cSHans J. Koch atomic_t event; 33beafc54cSHans J. Koch struct fasync_struct *async_queue; 34beafc54cSHans J. Koch wait_queue_head_t wait; 35beafc54cSHans J. Koch int vma_count; 36beafc54cSHans J. Koch struct uio_info *info; 3781e7c6a6SGreg Kroah-Hartman struct kobject *map_dir; 38beafc54cSHans J. Koch }; 39beafc54cSHans J. Koch 40beafc54cSHans J. Koch static int uio_major; 41beafc54cSHans J. Koch static DEFINE_IDR(uio_idr); 424f014691SJan Engelhardt static const struct file_operations uio_fops; 43beafc54cSHans J. Koch 44beafc54cSHans J. Koch /* UIO class infrastructure */ 45beafc54cSHans J. Koch static struct uio_class { 46beafc54cSHans J. Koch struct kref kref; 47beafc54cSHans J. Koch struct class *class; 48beafc54cSHans J. Koch } *uio_class; 49beafc54cSHans J. Koch 50beafc54cSHans J. Koch /* 51beafc54cSHans J. Koch * attributes 52beafc54cSHans J. Koch */ 53beafc54cSHans J. Koch 5481e7c6a6SGreg Kroah-Hartman struct uio_map { 5581e7c6a6SGreg Kroah-Hartman struct kobject kobj; 5681e7c6a6SGreg Kroah-Hartman struct uio_mem *mem; 57beafc54cSHans J. Koch }; 5881e7c6a6SGreg Kroah-Hartman #define to_map(map) container_of(map, struct uio_map, kobj) 59beafc54cSHans J. Koch 604f808bcdSBrandon Philips static ssize_t map_addr_show(struct uio_mem *mem, char *buf) 61beafc54cSHans J. Koch { 62beafc54cSHans J. Koch return sprintf(buf, "0x%lx\n", mem->addr); 63beafc54cSHans J. Koch } 64beafc54cSHans J. Koch 654f808bcdSBrandon Philips static ssize_t map_size_show(struct uio_mem *mem, char *buf) 664f808bcdSBrandon Philips { 674f808bcdSBrandon Philips return sprintf(buf, "0x%lx\n", mem->size); 684f808bcdSBrandon Philips } 694f808bcdSBrandon Philips 704f808bcdSBrandon Philips struct uio_sysfs_entry { 714f808bcdSBrandon Philips struct attribute attr; 724f808bcdSBrandon Philips ssize_t (*show)(struct uio_mem *, char *); 734f808bcdSBrandon Philips ssize_t (*store)(struct uio_mem *, const char *, size_t); 744f808bcdSBrandon Philips }; 754f808bcdSBrandon Philips 764f808bcdSBrandon Philips static struct uio_sysfs_entry addr_attribute = 774f808bcdSBrandon Philips __ATTR(addr, S_IRUGO, map_addr_show, NULL); 784f808bcdSBrandon Philips static struct uio_sysfs_entry size_attribute = 794f808bcdSBrandon Philips __ATTR(size, S_IRUGO, map_size_show, NULL); 80beafc54cSHans J. Koch 8181e7c6a6SGreg Kroah-Hartman static struct attribute *attrs[] = { 824f808bcdSBrandon Philips &addr_attribute.attr, 8381e7c6a6SGreg Kroah-Hartman &size_attribute.attr, 8481e7c6a6SGreg Kroah-Hartman NULL, /* need to NULL terminate the list of attributes */ 85beafc54cSHans J. Koch }; 86beafc54cSHans J. Koch 8781e7c6a6SGreg Kroah-Hartman static void map_release(struct kobject *kobj) 8881e7c6a6SGreg Kroah-Hartman { 8981e7c6a6SGreg Kroah-Hartman struct uio_map *map = to_map(kobj); 9081e7c6a6SGreg Kroah-Hartman kfree(map); 9181e7c6a6SGreg Kroah-Hartman } 9281e7c6a6SGreg Kroah-Hartman 934f808bcdSBrandon Philips static ssize_t map_type_show(struct kobject *kobj, struct attribute *attr, 944f808bcdSBrandon Philips char *buf) 954f808bcdSBrandon Philips { 964f808bcdSBrandon Philips struct uio_map *map = to_map(kobj); 974f808bcdSBrandon Philips struct uio_mem *mem = map->mem; 984f808bcdSBrandon Philips struct uio_sysfs_entry *entry; 994f808bcdSBrandon Philips 1004f808bcdSBrandon Philips entry = container_of(attr, struct uio_sysfs_entry, attr); 1014f808bcdSBrandon Philips 1024f808bcdSBrandon Philips if (!entry->show) 1034f808bcdSBrandon Philips return -EIO; 1044f808bcdSBrandon Philips 1054f808bcdSBrandon Philips return entry->show(mem, buf); 1064f808bcdSBrandon Philips } 1074f808bcdSBrandon Philips 1084f808bcdSBrandon Philips static struct sysfs_ops uio_sysfs_ops = { 1094f808bcdSBrandon Philips .show = map_type_show, 1104f808bcdSBrandon Philips }; 1114f808bcdSBrandon Philips 112beafc54cSHans J. Koch static struct kobj_type map_attr_type = { 11381e7c6a6SGreg Kroah-Hartman .release = map_release, 1144f808bcdSBrandon Philips .sysfs_ops = &uio_sysfs_ops, 11581e7c6a6SGreg Kroah-Hartman .default_attrs = attrs, 116beafc54cSHans J. Koch }; 117beafc54cSHans J. Koch 118beafc54cSHans J. Koch static ssize_t show_name(struct device *dev, 119beafc54cSHans J. Koch struct device_attribute *attr, char *buf) 120beafc54cSHans J. Koch { 121beafc54cSHans J. Koch struct uio_device *idev = dev_get_drvdata(dev); 122beafc54cSHans J. Koch if (idev) 123beafc54cSHans J. Koch return sprintf(buf, "%s\n", idev->info->name); 124beafc54cSHans J. Koch else 125beafc54cSHans J. Koch return -ENODEV; 126beafc54cSHans J. Koch } 127beafc54cSHans J. Koch static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); 128beafc54cSHans J. Koch 129beafc54cSHans J. Koch static ssize_t show_version(struct device *dev, 130beafc54cSHans J. Koch struct device_attribute *attr, char *buf) 131beafc54cSHans J. Koch { 132beafc54cSHans J. Koch struct uio_device *idev = dev_get_drvdata(dev); 133beafc54cSHans J. Koch if (idev) 134beafc54cSHans J. Koch return sprintf(buf, "%s\n", idev->info->version); 135beafc54cSHans J. Koch else 136beafc54cSHans J. Koch return -ENODEV; 137beafc54cSHans J. Koch } 138beafc54cSHans J. Koch static DEVICE_ATTR(version, S_IRUGO, show_version, NULL); 139beafc54cSHans J. Koch 140beafc54cSHans J. Koch static ssize_t show_event(struct device *dev, 141beafc54cSHans J. Koch struct device_attribute *attr, char *buf) 142beafc54cSHans J. Koch { 143beafc54cSHans J. Koch struct uio_device *idev = dev_get_drvdata(dev); 144beafc54cSHans J. Koch if (idev) 145beafc54cSHans J. Koch return sprintf(buf, "%u\n", 146beafc54cSHans J. Koch (unsigned int)atomic_read(&idev->event)); 147beafc54cSHans J. Koch else 148beafc54cSHans J. Koch return -ENODEV; 149beafc54cSHans J. Koch } 150beafc54cSHans J. Koch static DEVICE_ATTR(event, S_IRUGO, show_event, NULL); 151beafc54cSHans J. Koch 152beafc54cSHans J. Koch static struct attribute *uio_attrs[] = { 153beafc54cSHans J. Koch &dev_attr_name.attr, 154beafc54cSHans J. Koch &dev_attr_version.attr, 155beafc54cSHans J. Koch &dev_attr_event.attr, 156beafc54cSHans J. Koch NULL, 157beafc54cSHans J. Koch }; 158beafc54cSHans J. Koch 159beafc54cSHans J. Koch static struct attribute_group uio_attr_grp = { 160beafc54cSHans J. Koch .attrs = uio_attrs, 161beafc54cSHans J. Koch }; 162beafc54cSHans J. Koch 163beafc54cSHans J. Koch /* 164beafc54cSHans J. Koch * device functions 165beafc54cSHans J. Koch */ 166beafc54cSHans J. Koch static int uio_dev_add_attributes(struct uio_device *idev) 167beafc54cSHans J. Koch { 168beafc54cSHans J. Koch int ret; 169beafc54cSHans J. Koch int mi; 170beafc54cSHans J. Koch int map_found = 0; 171beafc54cSHans J. Koch struct uio_mem *mem; 17281e7c6a6SGreg Kroah-Hartman struct uio_map *map; 173beafc54cSHans J. Koch 174beafc54cSHans J. Koch ret = sysfs_create_group(&idev->dev->kobj, &uio_attr_grp); 175beafc54cSHans J. Koch if (ret) 176beafc54cSHans J. Koch goto err_group; 177beafc54cSHans J. Koch 178beafc54cSHans J. Koch for (mi = 0; mi < MAX_UIO_MAPS; mi++) { 179beafc54cSHans J. Koch mem = &idev->info->mem[mi]; 180beafc54cSHans J. Koch if (mem->size == 0) 181beafc54cSHans J. Koch break; 182beafc54cSHans J. Koch if (!map_found) { 183beafc54cSHans J. Koch map_found = 1; 18481e7c6a6SGreg Kroah-Hartman idev->map_dir = kobject_create_and_add("maps", 18581e7c6a6SGreg Kroah-Hartman &idev->dev->kobj); 18681e7c6a6SGreg Kroah-Hartman if (!idev->map_dir) 18781e7c6a6SGreg Kroah-Hartman goto err; 188beafc54cSHans J. Koch } 18981e7c6a6SGreg Kroah-Hartman map = kzalloc(sizeof(*map), GFP_KERNEL); 19081e7c6a6SGreg Kroah-Hartman if (!map) 19181e7c6a6SGreg Kroah-Hartman goto err; 192f9cb074bSGreg Kroah-Hartman kobject_init(&map->kobj, &map_attr_type); 19381e7c6a6SGreg Kroah-Hartman map->mem = mem; 19481e7c6a6SGreg Kroah-Hartman mem->map = map; 195b2d6db58SGreg Kroah-Hartman ret = kobject_add(&map->kobj, idev->map_dir, "map%d", mi); 196beafc54cSHans J. Koch if (ret) 19781e7c6a6SGreg Kroah-Hartman goto err; 19881e7c6a6SGreg Kroah-Hartman ret = kobject_uevent(&map->kobj, KOBJ_ADD); 19981e7c6a6SGreg Kroah-Hartman if (ret) 20081e7c6a6SGreg Kroah-Hartman goto err; 201beafc54cSHans J. Koch } 202beafc54cSHans J. Koch 203beafc54cSHans J. Koch return 0; 204beafc54cSHans J. Koch 20581e7c6a6SGreg Kroah-Hartman err: 206beafc54cSHans J. Koch for (mi--; mi>=0; mi--) { 207beafc54cSHans J. Koch mem = &idev->info->mem[mi]; 20881e7c6a6SGreg Kroah-Hartman map = mem->map; 209c10997f6SGreg Kroah-Hartman kobject_put(&map->kobj); 210beafc54cSHans J. Koch } 211c10997f6SGreg Kroah-Hartman kobject_put(idev->map_dir); 212beafc54cSHans J. Koch sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp); 213beafc54cSHans J. Koch err_group: 214beafc54cSHans J. Koch dev_err(idev->dev, "error creating sysfs files (%d)\n", ret); 215beafc54cSHans J. Koch return ret; 216beafc54cSHans J. Koch } 217beafc54cSHans J. Koch 218beafc54cSHans J. Koch static void uio_dev_del_attributes(struct uio_device *idev) 219beafc54cSHans J. Koch { 220beafc54cSHans J. Koch int mi; 221beafc54cSHans J. Koch struct uio_mem *mem; 222beafc54cSHans J. Koch for (mi = 0; mi < MAX_UIO_MAPS; mi++) { 223beafc54cSHans J. Koch mem = &idev->info->mem[mi]; 224beafc54cSHans J. Koch if (mem->size == 0) 225beafc54cSHans J. Koch break; 226c10997f6SGreg Kroah-Hartman kobject_put(&mem->map->kobj); 227beafc54cSHans J. Koch } 228c10997f6SGreg Kroah-Hartman kobject_put(idev->map_dir); 229beafc54cSHans J. Koch sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp); 230beafc54cSHans J. Koch } 231beafc54cSHans J. Koch 232beafc54cSHans J. Koch static int uio_get_minor(struct uio_device *idev) 233beafc54cSHans J. Koch { 234beafc54cSHans J. Koch static DEFINE_MUTEX(minor_lock); 235beafc54cSHans J. Koch int retval = -ENOMEM; 236beafc54cSHans J. Koch int id; 237beafc54cSHans J. Koch 238beafc54cSHans J. Koch mutex_lock(&minor_lock); 239beafc54cSHans J. Koch if (idr_pre_get(&uio_idr, GFP_KERNEL) == 0) 240beafc54cSHans J. Koch goto exit; 241beafc54cSHans J. Koch 242beafc54cSHans J. Koch retval = idr_get_new(&uio_idr, idev, &id); 243beafc54cSHans J. Koch if (retval < 0) { 244beafc54cSHans J. Koch if (retval == -EAGAIN) 245beafc54cSHans J. Koch retval = -ENOMEM; 246beafc54cSHans J. Koch goto exit; 247beafc54cSHans J. Koch } 248beafc54cSHans J. Koch idev->minor = id & MAX_ID_MASK; 249beafc54cSHans J. Koch exit: 250beafc54cSHans J. Koch mutex_unlock(&minor_lock); 251beafc54cSHans J. Koch return retval; 252beafc54cSHans J. Koch } 253beafc54cSHans J. Koch 254beafc54cSHans J. Koch static void uio_free_minor(struct uio_device *idev) 255beafc54cSHans J. Koch { 256beafc54cSHans J. Koch idr_remove(&uio_idr, idev->minor); 257beafc54cSHans J. Koch } 258beafc54cSHans J. Koch 259beafc54cSHans J. Koch /** 260beafc54cSHans J. Koch * uio_event_notify - trigger an interrupt event 261beafc54cSHans J. Koch * @info: UIO device capabilities 262beafc54cSHans J. Koch */ 263beafc54cSHans J. Koch void uio_event_notify(struct uio_info *info) 264beafc54cSHans J. Koch { 265beafc54cSHans J. Koch struct uio_device *idev = info->uio_dev; 266beafc54cSHans J. Koch 267beafc54cSHans J. Koch atomic_inc(&idev->event); 268beafc54cSHans J. Koch wake_up_interruptible(&idev->wait); 269beafc54cSHans J. Koch kill_fasync(&idev->async_queue, SIGIO, POLL_IN); 270beafc54cSHans J. Koch } 271beafc54cSHans J. Koch EXPORT_SYMBOL_GPL(uio_event_notify); 272beafc54cSHans J. Koch 273beafc54cSHans J. Koch /** 274beafc54cSHans J. Koch * uio_interrupt - hardware interrupt handler 275beafc54cSHans J. Koch * @irq: IRQ number, can be UIO_IRQ_CYCLIC for cyclic timer 276beafc54cSHans J. Koch * @dev_id: Pointer to the devices uio_device structure 277beafc54cSHans J. Koch */ 278beafc54cSHans J. Koch static irqreturn_t uio_interrupt(int irq, void *dev_id) 279beafc54cSHans J. Koch { 280beafc54cSHans J. Koch struct uio_device *idev = (struct uio_device *)dev_id; 281beafc54cSHans J. Koch irqreturn_t ret = idev->info->handler(irq, idev->info); 282beafc54cSHans J. Koch 283beafc54cSHans J. Koch if (ret == IRQ_HANDLED) 284beafc54cSHans J. Koch uio_event_notify(idev->info); 285beafc54cSHans J. Koch 286beafc54cSHans J. Koch return ret; 287beafc54cSHans J. Koch } 288beafc54cSHans J. Koch 289beafc54cSHans J. Koch struct uio_listener { 290beafc54cSHans J. Koch struct uio_device *dev; 291beafc54cSHans J. Koch s32 event_count; 292beafc54cSHans J. Koch }; 293beafc54cSHans J. Koch 294beafc54cSHans J. Koch static int uio_open(struct inode *inode, struct file *filep) 295beafc54cSHans J. Koch { 296beafc54cSHans J. Koch struct uio_device *idev; 297beafc54cSHans J. Koch struct uio_listener *listener; 298beafc54cSHans J. Koch int ret = 0; 299beafc54cSHans J. Koch 300fbc8a81dSJonathan Corbet lock_kernel(); 301beafc54cSHans J. Koch idev = idr_find(&uio_idr, iminor(inode)); 302fbc8a81dSJonathan Corbet if (!idev) { 303fbc8a81dSJonathan Corbet ret = -ENODEV; 304fbc8a81dSJonathan Corbet goto out; 305fbc8a81dSJonathan Corbet } 306beafc54cSHans J. Koch 307fbc8a81dSJonathan Corbet if (!try_module_get(idev->owner)) { 308fbc8a81dSJonathan Corbet ret = -ENODEV; 309fbc8a81dSJonathan Corbet goto out; 310fbc8a81dSJonathan Corbet } 311610ad506SUwe Kleine-König 312beafc54cSHans J. Koch listener = kmalloc(sizeof(*listener), GFP_KERNEL); 313610ad506SUwe Kleine-König if (!listener) { 314610ad506SUwe Kleine-König ret = -ENOMEM; 315610ad506SUwe Kleine-König goto err_alloc_listener; 316610ad506SUwe Kleine-König } 317beafc54cSHans J. Koch 318beafc54cSHans J. Koch listener->dev = idev; 319beafc54cSHans J. Koch listener->event_count = atomic_read(&idev->event); 320beafc54cSHans J. Koch filep->private_data = listener; 321beafc54cSHans J. Koch 322beafc54cSHans J. Koch if (idev->info->open) { 323beafc54cSHans J. Koch ret = idev->info->open(idev->info, inode); 324610ad506SUwe Kleine-König if (ret) 325610ad506SUwe Kleine-König goto err_infoopen; 326beafc54cSHans J. Koch } 327fbc8a81dSJonathan Corbet unlock_kernel(); 328610ad506SUwe Kleine-König return 0; 329610ad506SUwe Kleine-König 330610ad506SUwe Kleine-König err_infoopen: 331610ad506SUwe Kleine-König 332beafc54cSHans J. Koch kfree(listener); 333610ad506SUwe Kleine-König err_alloc_listener: 334610ad506SUwe Kleine-König 335610ad506SUwe Kleine-König module_put(idev->owner); 336beafc54cSHans J. Koch 337fbc8a81dSJonathan Corbet out: 338fbc8a81dSJonathan Corbet unlock_kernel(); 339beafc54cSHans J. Koch return ret; 340beafc54cSHans J. Koch } 341beafc54cSHans J. Koch 342beafc54cSHans J. Koch static int uio_fasync(int fd, struct file *filep, int on) 343beafc54cSHans J. Koch { 344beafc54cSHans J. Koch struct uio_listener *listener = filep->private_data; 345beafc54cSHans J. Koch struct uio_device *idev = listener->dev; 346beafc54cSHans J. Koch 347beafc54cSHans J. Koch return fasync_helper(fd, filep, on, &idev->async_queue); 348beafc54cSHans J. Koch } 349beafc54cSHans J. Koch 350beafc54cSHans J. Koch static int uio_release(struct inode *inode, struct file *filep) 351beafc54cSHans J. Koch { 352beafc54cSHans J. Koch int ret = 0; 353beafc54cSHans J. Koch struct uio_listener *listener = filep->private_data; 354beafc54cSHans J. Koch struct uio_device *idev = listener->dev; 355beafc54cSHans J. Koch 356610ad506SUwe Kleine-König if (idev->info->release) 357beafc54cSHans J. Koch ret = idev->info->release(idev->info, inode); 358610ad506SUwe Kleine-König 359beafc54cSHans J. Koch module_put(idev->owner); 360610ad506SUwe Kleine-König 361beafc54cSHans J. Koch if (filep->f_flags & FASYNC) 362beafc54cSHans J. Koch ret = uio_fasync(-1, filep, 0); 363beafc54cSHans J. Koch kfree(listener); 364beafc54cSHans J. Koch return ret; 365beafc54cSHans J. Koch } 366beafc54cSHans J. Koch 367beafc54cSHans J. Koch static unsigned int uio_poll(struct file *filep, poll_table *wait) 368beafc54cSHans J. Koch { 369beafc54cSHans J. Koch struct uio_listener *listener = filep->private_data; 370beafc54cSHans J. Koch struct uio_device *idev = listener->dev; 371beafc54cSHans J. Koch 372beafc54cSHans J. Koch if (idev->info->irq == UIO_IRQ_NONE) 373beafc54cSHans J. Koch return -EIO; 374beafc54cSHans J. Koch 375beafc54cSHans J. Koch poll_wait(filep, &idev->wait, wait); 376beafc54cSHans J. Koch if (listener->event_count != atomic_read(&idev->event)) 377beafc54cSHans J. Koch return POLLIN | POLLRDNORM; 378beafc54cSHans J. Koch return 0; 379beafc54cSHans J. Koch } 380beafc54cSHans J. Koch 381beafc54cSHans J. Koch static ssize_t uio_read(struct file *filep, char __user *buf, 382beafc54cSHans J. Koch size_t count, loff_t *ppos) 383beafc54cSHans J. Koch { 384beafc54cSHans J. Koch struct uio_listener *listener = filep->private_data; 385beafc54cSHans J. Koch struct uio_device *idev = listener->dev; 386beafc54cSHans J. Koch DECLARE_WAITQUEUE(wait, current); 387beafc54cSHans J. Koch ssize_t retval; 388beafc54cSHans J. Koch s32 event_count; 389beafc54cSHans J. Koch 390beafc54cSHans J. Koch if (idev->info->irq == UIO_IRQ_NONE) 391beafc54cSHans J. Koch return -EIO; 392beafc54cSHans J. Koch 393beafc54cSHans J. Koch if (count != sizeof(s32)) 394beafc54cSHans J. Koch return -EINVAL; 395beafc54cSHans J. Koch 396beafc54cSHans J. Koch add_wait_queue(&idev->wait, &wait); 397beafc54cSHans J. Koch 398beafc54cSHans J. Koch do { 399beafc54cSHans J. Koch set_current_state(TASK_INTERRUPTIBLE); 400beafc54cSHans J. Koch 401beafc54cSHans J. Koch event_count = atomic_read(&idev->event); 402beafc54cSHans J. Koch if (event_count != listener->event_count) { 403beafc54cSHans J. Koch if (copy_to_user(buf, &event_count, count)) 404beafc54cSHans J. Koch retval = -EFAULT; 405beafc54cSHans J. Koch else { 406beafc54cSHans J. Koch listener->event_count = event_count; 407beafc54cSHans J. Koch retval = count; 408beafc54cSHans J. Koch } 409beafc54cSHans J. Koch break; 410beafc54cSHans J. Koch } 411beafc54cSHans J. Koch 412beafc54cSHans J. Koch if (filep->f_flags & O_NONBLOCK) { 413beafc54cSHans J. Koch retval = -EAGAIN; 414beafc54cSHans J. Koch break; 415beafc54cSHans J. Koch } 416beafc54cSHans J. Koch 417beafc54cSHans J. Koch if (signal_pending(current)) { 418beafc54cSHans J. Koch retval = -ERESTARTSYS; 419beafc54cSHans J. Koch break; 420beafc54cSHans J. Koch } 421beafc54cSHans J. Koch schedule(); 422beafc54cSHans J. Koch } while (1); 423beafc54cSHans J. Koch 424beafc54cSHans J. Koch __set_current_state(TASK_RUNNING); 425beafc54cSHans J. Koch remove_wait_queue(&idev->wait, &wait); 426beafc54cSHans J. Koch 427beafc54cSHans J. Koch return retval; 428beafc54cSHans J. Koch } 429beafc54cSHans J. Koch 430beafc54cSHans J. Koch static int uio_find_mem_index(struct vm_area_struct *vma) 431beafc54cSHans J. Koch { 432beafc54cSHans J. Koch int mi; 433beafc54cSHans J. Koch struct uio_device *idev = vma->vm_private_data; 434beafc54cSHans J. Koch 435beafc54cSHans J. Koch for (mi = 0; mi < MAX_UIO_MAPS; mi++) { 436beafc54cSHans J. Koch if (idev->info->mem[mi].size == 0) 437beafc54cSHans J. Koch return -1; 438beafc54cSHans J. Koch if (vma->vm_pgoff == mi) 439beafc54cSHans J. Koch return mi; 440beafc54cSHans J. Koch } 441beafc54cSHans J. Koch return -1; 442beafc54cSHans J. Koch } 443beafc54cSHans J. Koch 444beafc54cSHans J. Koch static void uio_vma_open(struct vm_area_struct *vma) 445beafc54cSHans J. Koch { 446beafc54cSHans J. Koch struct uio_device *idev = vma->vm_private_data; 447beafc54cSHans J. Koch idev->vma_count++; 448beafc54cSHans J. Koch } 449beafc54cSHans J. Koch 450beafc54cSHans J. Koch static void uio_vma_close(struct vm_area_struct *vma) 451beafc54cSHans J. Koch { 452beafc54cSHans J. Koch struct uio_device *idev = vma->vm_private_data; 453beafc54cSHans J. Koch idev->vma_count--; 454beafc54cSHans J. Koch } 455beafc54cSHans J. Koch 456a18b630dSNick Piggin static int uio_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 457beafc54cSHans J. Koch { 458beafc54cSHans J. Koch struct uio_device *idev = vma->vm_private_data; 459a18b630dSNick Piggin struct page *page; 460beafc54cSHans J. Koch 461beafc54cSHans J. Koch int mi = uio_find_mem_index(vma); 462beafc54cSHans J. Koch if (mi < 0) 463a18b630dSNick Piggin return VM_FAULT_SIGBUS; 464beafc54cSHans J. Koch 465beafc54cSHans J. Koch if (idev->info->mem[mi].memtype == UIO_MEM_LOGICAL) 466beafc54cSHans J. Koch page = virt_to_page(idev->info->mem[mi].addr); 467beafc54cSHans J. Koch else 468beafc54cSHans J. Koch page = vmalloc_to_page((void*)idev->info->mem[mi].addr); 469beafc54cSHans J. Koch get_page(page); 470a18b630dSNick Piggin vmf->page = page; 471a18b630dSNick Piggin return 0; 472beafc54cSHans J. Koch } 473beafc54cSHans J. Koch 474beafc54cSHans J. Koch static struct vm_operations_struct uio_vm_ops = { 475beafc54cSHans J. Koch .open = uio_vma_open, 476beafc54cSHans J. Koch .close = uio_vma_close, 477a18b630dSNick Piggin .fault = uio_vma_fault, 478beafc54cSHans J. Koch }; 479beafc54cSHans J. Koch 480beafc54cSHans J. Koch static int uio_mmap_physical(struct vm_area_struct *vma) 481beafc54cSHans J. Koch { 482beafc54cSHans J. Koch struct uio_device *idev = vma->vm_private_data; 483beafc54cSHans J. Koch int mi = uio_find_mem_index(vma); 484beafc54cSHans J. Koch if (mi < 0) 485beafc54cSHans J. Koch return -EINVAL; 486beafc54cSHans J. Koch 487beafc54cSHans J. Koch vma->vm_flags |= VM_IO | VM_RESERVED; 488beafc54cSHans J. Koch 489c9698d6bSJean-Samuel Chenard vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); 490c9698d6bSJean-Samuel Chenard 491beafc54cSHans J. Koch return remap_pfn_range(vma, 492beafc54cSHans J. Koch vma->vm_start, 493beafc54cSHans J. Koch idev->info->mem[mi].addr >> PAGE_SHIFT, 494beafc54cSHans J. Koch vma->vm_end - vma->vm_start, 495beafc54cSHans J. Koch vma->vm_page_prot); 496beafc54cSHans J. Koch } 497beafc54cSHans J. Koch 498beafc54cSHans J. Koch static int uio_mmap_logical(struct vm_area_struct *vma) 499beafc54cSHans J. Koch { 500beafc54cSHans J. Koch vma->vm_flags |= VM_RESERVED; 501beafc54cSHans J. Koch vma->vm_ops = &uio_vm_ops; 502beafc54cSHans J. Koch uio_vma_open(vma); 503beafc54cSHans J. Koch return 0; 504beafc54cSHans J. Koch } 505beafc54cSHans J. Koch 506beafc54cSHans J. Koch static int uio_mmap(struct file *filep, struct vm_area_struct *vma) 507beafc54cSHans J. Koch { 508beafc54cSHans J. Koch struct uio_listener *listener = filep->private_data; 509beafc54cSHans J. Koch struct uio_device *idev = listener->dev; 510beafc54cSHans J. Koch int mi; 511beafc54cSHans J. Koch unsigned long requested_pages, actual_pages; 512beafc54cSHans J. Koch int ret = 0; 513beafc54cSHans J. Koch 514beafc54cSHans J. Koch if (vma->vm_end < vma->vm_start) 515beafc54cSHans J. Koch return -EINVAL; 516beafc54cSHans J. Koch 517beafc54cSHans J. Koch vma->vm_private_data = idev; 518beafc54cSHans J. Koch 519beafc54cSHans J. Koch mi = uio_find_mem_index(vma); 520beafc54cSHans J. Koch if (mi < 0) 521beafc54cSHans J. Koch return -EINVAL; 522beafc54cSHans J. Koch 523beafc54cSHans J. Koch requested_pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; 524beafc54cSHans J. Koch actual_pages = (idev->info->mem[mi].size + PAGE_SIZE -1) >> PAGE_SHIFT; 525beafc54cSHans J. Koch if (requested_pages > actual_pages) 526beafc54cSHans J. Koch return -EINVAL; 527beafc54cSHans J. Koch 528beafc54cSHans J. Koch if (idev->info->mmap) { 529beafc54cSHans J. Koch ret = idev->info->mmap(idev->info, vma); 530beafc54cSHans J. Koch return ret; 531beafc54cSHans J. Koch } 532beafc54cSHans J. Koch 533beafc54cSHans J. Koch switch (idev->info->mem[mi].memtype) { 534beafc54cSHans J. Koch case UIO_MEM_PHYS: 535beafc54cSHans J. Koch return uio_mmap_physical(vma); 536beafc54cSHans J. Koch case UIO_MEM_LOGICAL: 537beafc54cSHans J. Koch case UIO_MEM_VIRTUAL: 538beafc54cSHans J. Koch return uio_mmap_logical(vma); 539beafc54cSHans J. Koch default: 540beafc54cSHans J. Koch return -EINVAL; 541beafc54cSHans J. Koch } 542beafc54cSHans J. Koch } 543beafc54cSHans J. Koch 5444f014691SJan Engelhardt static const struct file_operations uio_fops = { 545beafc54cSHans J. Koch .owner = THIS_MODULE, 546beafc54cSHans J. Koch .open = uio_open, 547beafc54cSHans J. Koch .release = uio_release, 548beafc54cSHans J. Koch .read = uio_read, 549beafc54cSHans J. Koch .mmap = uio_mmap, 550beafc54cSHans J. Koch .poll = uio_poll, 551beafc54cSHans J. Koch .fasync = uio_fasync, 552beafc54cSHans J. Koch }; 553beafc54cSHans J. Koch 554beafc54cSHans J. Koch static int uio_major_init(void) 555beafc54cSHans J. Koch { 556beafc54cSHans J. Koch uio_major = register_chrdev(0, "uio", &uio_fops); 557beafc54cSHans J. Koch if (uio_major < 0) 558beafc54cSHans J. Koch return uio_major; 559beafc54cSHans J. Koch return 0; 560beafc54cSHans J. Koch } 561beafc54cSHans J. Koch 562beafc54cSHans J. Koch static void uio_major_cleanup(void) 563beafc54cSHans J. Koch { 564beafc54cSHans J. Koch unregister_chrdev(uio_major, "uio"); 565beafc54cSHans J. Koch } 566beafc54cSHans J. Koch 567beafc54cSHans J. Koch static int init_uio_class(void) 568beafc54cSHans J. Koch { 569beafc54cSHans J. Koch int ret = 0; 570beafc54cSHans J. Koch 571beafc54cSHans J. Koch if (uio_class != NULL) { 572beafc54cSHans J. Koch kref_get(&uio_class->kref); 573beafc54cSHans J. Koch goto exit; 574beafc54cSHans J. Koch } 575beafc54cSHans J. Koch 576beafc54cSHans J. Koch /* This is the first time in here, set everything up properly */ 577beafc54cSHans J. Koch ret = uio_major_init(); 578beafc54cSHans J. Koch if (ret) 579beafc54cSHans J. Koch goto exit; 580beafc54cSHans J. Koch 581beafc54cSHans J. Koch uio_class = kzalloc(sizeof(*uio_class), GFP_KERNEL); 582beafc54cSHans J. Koch if (!uio_class) { 583beafc54cSHans J. Koch ret = -ENOMEM; 584beafc54cSHans J. Koch goto err_kzalloc; 585beafc54cSHans J. Koch } 586beafc54cSHans J. Koch 587beafc54cSHans J. Koch kref_init(&uio_class->kref); 588beafc54cSHans J. Koch uio_class->class = class_create(THIS_MODULE, "uio"); 589beafc54cSHans J. Koch if (IS_ERR(uio_class->class)) { 590beafc54cSHans J. Koch ret = IS_ERR(uio_class->class); 591beafc54cSHans J. Koch printk(KERN_ERR "class_create failed for uio\n"); 592beafc54cSHans J. Koch goto err_class_create; 593beafc54cSHans J. Koch } 594beafc54cSHans J. Koch return 0; 595beafc54cSHans J. Koch 596beafc54cSHans J. Koch err_class_create: 597beafc54cSHans J. Koch kfree(uio_class); 598beafc54cSHans J. Koch uio_class = NULL; 599beafc54cSHans J. Koch err_kzalloc: 600beafc54cSHans J. Koch uio_major_cleanup(); 601beafc54cSHans J. Koch exit: 602beafc54cSHans J. Koch return ret; 603beafc54cSHans J. Koch } 604beafc54cSHans J. Koch 605beafc54cSHans J. Koch static void release_uio_class(struct kref *kref) 606beafc54cSHans J. Koch { 607beafc54cSHans J. Koch /* Ok, we cheat as we know we only have one uio_class */ 608beafc54cSHans J. Koch class_destroy(uio_class->class); 609beafc54cSHans J. Koch kfree(uio_class); 610beafc54cSHans J. Koch uio_major_cleanup(); 611beafc54cSHans J. Koch uio_class = NULL; 612beafc54cSHans J. Koch } 613beafc54cSHans J. Koch 614beafc54cSHans J. Koch static void uio_class_destroy(void) 615beafc54cSHans J. Koch { 616beafc54cSHans J. Koch if (uio_class) 617beafc54cSHans J. Koch kref_put(&uio_class->kref, release_uio_class); 618beafc54cSHans J. Koch } 619beafc54cSHans J. Koch 620beafc54cSHans J. Koch /** 621beafc54cSHans J. Koch * uio_register_device - register a new userspace IO device 622beafc54cSHans J. Koch * @owner: module that creates the new device 623beafc54cSHans J. Koch * @parent: parent device 624beafc54cSHans J. Koch * @info: UIO device capabilities 625beafc54cSHans J. Koch * 626beafc54cSHans J. Koch * returns zero on success or a negative error code. 627beafc54cSHans J. Koch */ 628beafc54cSHans J. Koch int __uio_register_device(struct module *owner, 629beafc54cSHans J. Koch struct device *parent, 630beafc54cSHans J. Koch struct uio_info *info) 631beafc54cSHans J. Koch { 632beafc54cSHans J. Koch struct uio_device *idev; 633beafc54cSHans J. Koch int ret = 0; 634beafc54cSHans J. Koch 635beafc54cSHans J. Koch if (!parent || !info || !info->name || !info->version) 636beafc54cSHans J. Koch return -EINVAL; 637beafc54cSHans J. Koch 638beafc54cSHans J. Koch info->uio_dev = NULL; 639beafc54cSHans J. Koch 640beafc54cSHans J. Koch ret = init_uio_class(); 641beafc54cSHans J. Koch if (ret) 642beafc54cSHans J. Koch return ret; 643beafc54cSHans J. Koch 644beafc54cSHans J. Koch idev = kzalloc(sizeof(*idev), GFP_KERNEL); 645beafc54cSHans J. Koch if (!idev) { 646beafc54cSHans J. Koch ret = -ENOMEM; 647beafc54cSHans J. Koch goto err_kzalloc; 648beafc54cSHans J. Koch } 649beafc54cSHans J. Koch 650beafc54cSHans J. Koch idev->owner = owner; 651beafc54cSHans J. Koch idev->info = info; 652beafc54cSHans J. Koch init_waitqueue_head(&idev->wait); 653beafc54cSHans J. Koch atomic_set(&idev->event, 0); 654beafc54cSHans J. Koch 655beafc54cSHans J. Koch ret = uio_get_minor(idev); 656beafc54cSHans J. Koch if (ret) 657beafc54cSHans J. Koch goto err_get_minor; 658beafc54cSHans J. Koch 659beafc54cSHans J. Koch idev->dev = device_create(uio_class->class, parent, 660beafc54cSHans J. Koch MKDEV(uio_major, idev->minor), 661beafc54cSHans J. Koch "uio%d", idev->minor); 662beafc54cSHans J. Koch if (IS_ERR(idev->dev)) { 663beafc54cSHans J. Koch printk(KERN_ERR "UIO: device register failed\n"); 664beafc54cSHans J. Koch ret = PTR_ERR(idev->dev); 665beafc54cSHans J. Koch goto err_device_create; 666beafc54cSHans J. Koch } 667beafc54cSHans J. Koch dev_set_drvdata(idev->dev, idev); 668beafc54cSHans J. Koch 669beafc54cSHans J. Koch ret = uio_dev_add_attributes(idev); 670beafc54cSHans J. Koch if (ret) 671beafc54cSHans J. Koch goto err_uio_dev_add_attributes; 672beafc54cSHans J. Koch 673beafc54cSHans J. Koch info->uio_dev = idev; 674beafc54cSHans J. Koch 675beafc54cSHans J. Koch if (idev->info->irq >= 0) { 676beafc54cSHans J. Koch ret = request_irq(idev->info->irq, uio_interrupt, 677beafc54cSHans J. Koch idev->info->irq_flags, idev->info->name, idev); 678beafc54cSHans J. Koch if (ret) 679beafc54cSHans J. Koch goto err_request_irq; 680beafc54cSHans J. Koch } 681beafc54cSHans J. Koch 682beafc54cSHans J. Koch return 0; 683beafc54cSHans J. Koch 684beafc54cSHans J. Koch err_request_irq: 685beafc54cSHans J. Koch uio_dev_del_attributes(idev); 686beafc54cSHans J. Koch err_uio_dev_add_attributes: 687beafc54cSHans J. Koch device_destroy(uio_class->class, MKDEV(uio_major, idev->minor)); 688beafc54cSHans J. Koch err_device_create: 689beafc54cSHans J. Koch uio_free_minor(idev); 690beafc54cSHans J. Koch err_get_minor: 691beafc54cSHans J. Koch kfree(idev); 692beafc54cSHans J. Koch err_kzalloc: 693beafc54cSHans J. Koch uio_class_destroy(); 694beafc54cSHans J. Koch return ret; 695beafc54cSHans J. Koch } 696beafc54cSHans J. Koch EXPORT_SYMBOL_GPL(__uio_register_device); 697beafc54cSHans J. Koch 698beafc54cSHans J. Koch /** 699beafc54cSHans J. Koch * uio_unregister_device - unregister a industrial IO device 700beafc54cSHans J. Koch * @info: UIO device capabilities 701beafc54cSHans J. Koch * 702beafc54cSHans J. Koch */ 703beafc54cSHans J. Koch void uio_unregister_device(struct uio_info *info) 704beafc54cSHans J. Koch { 705beafc54cSHans J. Koch struct uio_device *idev; 706beafc54cSHans J. Koch 707beafc54cSHans J. Koch if (!info || !info->uio_dev) 708beafc54cSHans J. Koch return; 709beafc54cSHans J. Koch 710beafc54cSHans J. Koch idev = info->uio_dev; 711beafc54cSHans J. Koch 712beafc54cSHans J. Koch uio_free_minor(idev); 713beafc54cSHans J. Koch 714beafc54cSHans J. Koch if (info->irq >= 0) 715beafc54cSHans J. Koch free_irq(info->irq, idev); 716beafc54cSHans J. Koch 717beafc54cSHans J. Koch uio_dev_del_attributes(idev); 718beafc54cSHans J. Koch 719beafc54cSHans J. Koch dev_set_drvdata(idev->dev, NULL); 720beafc54cSHans J. Koch device_destroy(uio_class->class, MKDEV(uio_major, idev->minor)); 721beafc54cSHans J. Koch kfree(idev); 722beafc54cSHans J. Koch uio_class_destroy(); 723beafc54cSHans J. Koch 724beafc54cSHans J. Koch return; 725beafc54cSHans J. Koch } 726beafc54cSHans J. Koch EXPORT_SYMBOL_GPL(uio_unregister_device); 727beafc54cSHans J. Koch 728beafc54cSHans J. Koch static int __init uio_init(void) 729beafc54cSHans J. Koch { 730beafc54cSHans J. Koch return 0; 731beafc54cSHans J. Koch } 732beafc54cSHans J. Koch 733beafc54cSHans J. Koch static void __exit uio_exit(void) 734beafc54cSHans J. Koch { 735beafc54cSHans J. Koch } 736beafc54cSHans J. Koch 737beafc54cSHans J. Koch module_init(uio_init) 738beafc54cSHans J. Koch module_exit(uio_exit) 739beafc54cSHans J. Koch MODULE_LICENSE("GPL v2"); 740