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); 42beafc54cSHans J. Koch static 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 60beafc54cSHans J. Koch 6181e7c6a6SGreg Kroah-Hartman static ssize_t map_attr_show(struct kobject *kobj, struct kobj_attribute *attr, 62beafc54cSHans J. Koch char *buf) 63beafc54cSHans J. Koch { 6481e7c6a6SGreg Kroah-Hartman struct uio_map *map = to_map(kobj); 6581e7c6a6SGreg Kroah-Hartman struct uio_mem *mem = map->mem; 66beafc54cSHans J. Koch 6781e7c6a6SGreg Kroah-Hartman if (strncmp(attr->attr.name, "addr", 4) == 0) 68beafc54cSHans J. Koch return sprintf(buf, "0x%lx\n", mem->addr); 69beafc54cSHans J. Koch 7081e7c6a6SGreg Kroah-Hartman if (strncmp(attr->attr.name, "size", 4) == 0) 71beafc54cSHans J. Koch return sprintf(buf, "0x%lx\n", mem->size); 72beafc54cSHans J. Koch 73beafc54cSHans J. Koch return -ENODEV; 74beafc54cSHans J. Koch } 75beafc54cSHans J. Koch 7681e7c6a6SGreg Kroah-Hartman static struct kobj_attribute attr_attribute = 7781e7c6a6SGreg Kroah-Hartman __ATTR(addr, S_IRUGO, map_attr_show, NULL); 7881e7c6a6SGreg Kroah-Hartman static struct kobj_attribute size_attribute = 7981e7c6a6SGreg Kroah-Hartman __ATTR(size, S_IRUGO, map_attr_show, NULL); 80beafc54cSHans J. Koch 8181e7c6a6SGreg Kroah-Hartman static struct attribute *attrs[] = { 8281e7c6a6SGreg Kroah-Hartman &attr_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 93beafc54cSHans J. Koch static struct kobj_type map_attr_type = { 9481e7c6a6SGreg Kroah-Hartman .release = map_release, 9581e7c6a6SGreg Kroah-Hartman .default_attrs = attrs, 96beafc54cSHans J. Koch }; 97beafc54cSHans J. Koch 98beafc54cSHans J. Koch static ssize_t show_name(struct device *dev, 99beafc54cSHans J. Koch struct device_attribute *attr, char *buf) 100beafc54cSHans J. Koch { 101beafc54cSHans J. Koch struct uio_device *idev = dev_get_drvdata(dev); 102beafc54cSHans J. Koch if (idev) 103beafc54cSHans J. Koch return sprintf(buf, "%s\n", idev->info->name); 104beafc54cSHans J. Koch else 105beafc54cSHans J. Koch return -ENODEV; 106beafc54cSHans J. Koch } 107beafc54cSHans J. Koch static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); 108beafc54cSHans J. Koch 109beafc54cSHans J. Koch static ssize_t show_version(struct device *dev, 110beafc54cSHans J. Koch struct device_attribute *attr, char *buf) 111beafc54cSHans J. Koch { 112beafc54cSHans J. Koch struct uio_device *idev = dev_get_drvdata(dev); 113beafc54cSHans J. Koch if (idev) 114beafc54cSHans J. Koch return sprintf(buf, "%s\n", idev->info->version); 115beafc54cSHans J. Koch else 116beafc54cSHans J. Koch return -ENODEV; 117beafc54cSHans J. Koch } 118beafc54cSHans J. Koch static DEVICE_ATTR(version, S_IRUGO, show_version, NULL); 119beafc54cSHans J. Koch 120beafc54cSHans J. Koch static ssize_t show_event(struct device *dev, 121beafc54cSHans J. Koch struct device_attribute *attr, char *buf) 122beafc54cSHans J. Koch { 123beafc54cSHans J. Koch struct uio_device *idev = dev_get_drvdata(dev); 124beafc54cSHans J. Koch if (idev) 125beafc54cSHans J. Koch return sprintf(buf, "%u\n", 126beafc54cSHans J. Koch (unsigned int)atomic_read(&idev->event)); 127beafc54cSHans J. Koch else 128beafc54cSHans J. Koch return -ENODEV; 129beafc54cSHans J. Koch } 130beafc54cSHans J. Koch static DEVICE_ATTR(event, S_IRUGO, show_event, NULL); 131beafc54cSHans J. Koch 132beafc54cSHans J. Koch static struct attribute *uio_attrs[] = { 133beafc54cSHans J. Koch &dev_attr_name.attr, 134beafc54cSHans J. Koch &dev_attr_version.attr, 135beafc54cSHans J. Koch &dev_attr_event.attr, 136beafc54cSHans J. Koch NULL, 137beafc54cSHans J. Koch }; 138beafc54cSHans J. Koch 139beafc54cSHans J. Koch static struct attribute_group uio_attr_grp = { 140beafc54cSHans J. Koch .attrs = uio_attrs, 141beafc54cSHans J. Koch }; 142beafc54cSHans J. Koch 143beafc54cSHans J. Koch /* 144beafc54cSHans J. Koch * device functions 145beafc54cSHans J. Koch */ 146beafc54cSHans J. Koch static int uio_dev_add_attributes(struct uio_device *idev) 147beafc54cSHans J. Koch { 148beafc54cSHans J. Koch int ret; 149beafc54cSHans J. Koch int mi; 150beafc54cSHans J. Koch int map_found = 0; 151beafc54cSHans J. Koch struct uio_mem *mem; 15281e7c6a6SGreg Kroah-Hartman struct uio_map *map; 153beafc54cSHans J. Koch 154beafc54cSHans J. Koch ret = sysfs_create_group(&idev->dev->kobj, &uio_attr_grp); 155beafc54cSHans J. Koch if (ret) 156beafc54cSHans J. Koch goto err_group; 157beafc54cSHans J. Koch 158beafc54cSHans J. Koch for (mi = 0; mi < MAX_UIO_MAPS; mi++) { 159beafc54cSHans J. Koch mem = &idev->info->mem[mi]; 160beafc54cSHans J. Koch if (mem->size == 0) 161beafc54cSHans J. Koch break; 162beafc54cSHans J. Koch if (!map_found) { 163beafc54cSHans J. Koch map_found = 1; 16481e7c6a6SGreg Kroah-Hartman idev->map_dir = kobject_create_and_add("maps", 16581e7c6a6SGreg Kroah-Hartman &idev->dev->kobj); 16681e7c6a6SGreg Kroah-Hartman if (!idev->map_dir) 16781e7c6a6SGreg Kroah-Hartman goto err; 168beafc54cSHans J. Koch } 16981e7c6a6SGreg Kroah-Hartman map = kzalloc(sizeof(*map), GFP_KERNEL); 17081e7c6a6SGreg Kroah-Hartman if (!map) 17181e7c6a6SGreg Kroah-Hartman goto err; 172f9cb074bSGreg Kroah-Hartman kobject_init(&map->kobj, &map_attr_type); 17381e7c6a6SGreg Kroah-Hartman map->mem = mem; 17481e7c6a6SGreg Kroah-Hartman mem->map = map; 175b2d6db58SGreg Kroah-Hartman ret = kobject_add(&map->kobj, idev->map_dir, "map%d", mi); 176beafc54cSHans J. Koch if (ret) 17781e7c6a6SGreg Kroah-Hartman goto err; 17881e7c6a6SGreg Kroah-Hartman ret = kobject_uevent(&map->kobj, KOBJ_ADD); 17981e7c6a6SGreg Kroah-Hartman if (ret) 18081e7c6a6SGreg Kroah-Hartman goto err; 181beafc54cSHans J. Koch } 182beafc54cSHans J. Koch 183beafc54cSHans J. Koch return 0; 184beafc54cSHans J. Koch 18581e7c6a6SGreg Kroah-Hartman err: 186beafc54cSHans J. Koch for (mi--; mi>=0; mi--) { 187beafc54cSHans J. Koch mem = &idev->info->mem[mi]; 18881e7c6a6SGreg Kroah-Hartman map = mem->map; 18981e7c6a6SGreg Kroah-Hartman kobject_unregister(&map->kobj); 190beafc54cSHans J. Koch } 19181e7c6a6SGreg Kroah-Hartman kobject_unregister(idev->map_dir); 192beafc54cSHans J. Koch sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp); 193beafc54cSHans J. Koch err_group: 194beafc54cSHans J. Koch dev_err(idev->dev, "error creating sysfs files (%d)\n", ret); 195beafc54cSHans J. Koch return ret; 196beafc54cSHans J. Koch } 197beafc54cSHans J. Koch 198beafc54cSHans J. Koch static void uio_dev_del_attributes(struct uio_device *idev) 199beafc54cSHans J. Koch { 200beafc54cSHans J. Koch int mi; 201beafc54cSHans J. Koch struct uio_mem *mem; 202beafc54cSHans J. Koch for (mi = 0; mi < MAX_UIO_MAPS; mi++) { 203beafc54cSHans J. Koch mem = &idev->info->mem[mi]; 204beafc54cSHans J. Koch if (mem->size == 0) 205beafc54cSHans J. Koch break; 20681e7c6a6SGreg Kroah-Hartman kobject_unregister(&mem->map->kobj); 207beafc54cSHans J. Koch } 20881e7c6a6SGreg Kroah-Hartman kobject_unregister(idev->map_dir); 209beafc54cSHans J. Koch sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp); 210beafc54cSHans J. Koch } 211beafc54cSHans J. Koch 212beafc54cSHans J. Koch static int uio_get_minor(struct uio_device *idev) 213beafc54cSHans J. Koch { 214beafc54cSHans J. Koch static DEFINE_MUTEX(minor_lock); 215beafc54cSHans J. Koch int retval = -ENOMEM; 216beafc54cSHans J. Koch int id; 217beafc54cSHans J. Koch 218beafc54cSHans J. Koch mutex_lock(&minor_lock); 219beafc54cSHans J. Koch if (idr_pre_get(&uio_idr, GFP_KERNEL) == 0) 220beafc54cSHans J. Koch goto exit; 221beafc54cSHans J. Koch 222beafc54cSHans J. Koch retval = idr_get_new(&uio_idr, idev, &id); 223beafc54cSHans J. Koch if (retval < 0) { 224beafc54cSHans J. Koch if (retval == -EAGAIN) 225beafc54cSHans J. Koch retval = -ENOMEM; 226beafc54cSHans J. Koch goto exit; 227beafc54cSHans J. Koch } 228beafc54cSHans J. Koch idev->minor = id & MAX_ID_MASK; 229beafc54cSHans J. Koch exit: 230beafc54cSHans J. Koch mutex_unlock(&minor_lock); 231beafc54cSHans J. Koch return retval; 232beafc54cSHans J. Koch } 233beafc54cSHans J. Koch 234beafc54cSHans J. Koch static void uio_free_minor(struct uio_device *idev) 235beafc54cSHans J. Koch { 236beafc54cSHans J. Koch idr_remove(&uio_idr, idev->minor); 237beafc54cSHans J. Koch } 238beafc54cSHans J. Koch 239beafc54cSHans J. Koch /** 240beafc54cSHans J. Koch * uio_event_notify - trigger an interrupt event 241beafc54cSHans J. Koch * @info: UIO device capabilities 242beafc54cSHans J. Koch */ 243beafc54cSHans J. Koch void uio_event_notify(struct uio_info *info) 244beafc54cSHans J. Koch { 245beafc54cSHans J. Koch struct uio_device *idev = info->uio_dev; 246beafc54cSHans J. Koch 247beafc54cSHans J. Koch atomic_inc(&idev->event); 248beafc54cSHans J. Koch wake_up_interruptible(&idev->wait); 249beafc54cSHans J. Koch kill_fasync(&idev->async_queue, SIGIO, POLL_IN); 250beafc54cSHans J. Koch } 251beafc54cSHans J. Koch EXPORT_SYMBOL_GPL(uio_event_notify); 252beafc54cSHans J. Koch 253beafc54cSHans J. Koch /** 254beafc54cSHans J. Koch * uio_interrupt - hardware interrupt handler 255beafc54cSHans J. Koch * @irq: IRQ number, can be UIO_IRQ_CYCLIC for cyclic timer 256beafc54cSHans J. Koch * @dev_id: Pointer to the devices uio_device structure 257beafc54cSHans J. Koch */ 258beafc54cSHans J. Koch static irqreturn_t uio_interrupt(int irq, void *dev_id) 259beafc54cSHans J. Koch { 260beafc54cSHans J. Koch struct uio_device *idev = (struct uio_device *)dev_id; 261beafc54cSHans J. Koch irqreturn_t ret = idev->info->handler(irq, idev->info); 262beafc54cSHans J. Koch 263beafc54cSHans J. Koch if (ret == IRQ_HANDLED) 264beafc54cSHans J. Koch uio_event_notify(idev->info); 265beafc54cSHans J. Koch 266beafc54cSHans J. Koch return ret; 267beafc54cSHans J. Koch } 268beafc54cSHans J. Koch 269beafc54cSHans J. Koch struct uio_listener { 270beafc54cSHans J. Koch struct uio_device *dev; 271beafc54cSHans J. Koch s32 event_count; 272beafc54cSHans J. Koch }; 273beafc54cSHans J. Koch 274beafc54cSHans J. Koch static int uio_open(struct inode *inode, struct file *filep) 275beafc54cSHans J. Koch { 276beafc54cSHans J. Koch struct uio_device *idev; 277beafc54cSHans J. Koch struct uio_listener *listener; 278beafc54cSHans J. Koch int ret = 0; 279beafc54cSHans J. Koch 280beafc54cSHans J. Koch idev = idr_find(&uio_idr, iminor(inode)); 281beafc54cSHans J. Koch if (!idev) 282beafc54cSHans J. Koch return -ENODEV; 283beafc54cSHans J. Koch 284beafc54cSHans J. Koch listener = kmalloc(sizeof(*listener), GFP_KERNEL); 285beafc54cSHans J. Koch if (!listener) 286beafc54cSHans J. Koch return -ENOMEM; 287beafc54cSHans J. Koch 288beafc54cSHans J. Koch listener->dev = idev; 289beafc54cSHans J. Koch listener->event_count = atomic_read(&idev->event); 290beafc54cSHans J. Koch filep->private_data = listener; 291beafc54cSHans J. Koch 292beafc54cSHans J. Koch if (idev->info->open) { 293beafc54cSHans J. Koch if (!try_module_get(idev->owner)) 294beafc54cSHans J. Koch return -ENODEV; 295beafc54cSHans J. Koch ret = idev->info->open(idev->info, inode); 296beafc54cSHans J. Koch module_put(idev->owner); 297beafc54cSHans J. Koch } 298beafc54cSHans J. Koch 299beafc54cSHans J. Koch if (ret) 300beafc54cSHans J. Koch kfree(listener); 301beafc54cSHans J. Koch 302beafc54cSHans J. Koch return ret; 303beafc54cSHans J. Koch } 304beafc54cSHans J. Koch 305beafc54cSHans J. Koch static int uio_fasync(int fd, struct file *filep, int on) 306beafc54cSHans J. Koch { 307beafc54cSHans J. Koch struct uio_listener *listener = filep->private_data; 308beafc54cSHans J. Koch struct uio_device *idev = listener->dev; 309beafc54cSHans J. Koch 310beafc54cSHans J. Koch return fasync_helper(fd, filep, on, &idev->async_queue); 311beafc54cSHans J. Koch } 312beafc54cSHans J. Koch 313beafc54cSHans J. Koch static int uio_release(struct inode *inode, struct file *filep) 314beafc54cSHans J. Koch { 315beafc54cSHans J. Koch int ret = 0; 316beafc54cSHans J. Koch struct uio_listener *listener = filep->private_data; 317beafc54cSHans J. Koch struct uio_device *idev = listener->dev; 318beafc54cSHans J. Koch 319beafc54cSHans J. Koch if (idev->info->release) { 320beafc54cSHans J. Koch if (!try_module_get(idev->owner)) 321beafc54cSHans J. Koch return -ENODEV; 322beafc54cSHans J. Koch ret = idev->info->release(idev->info, inode); 323beafc54cSHans J. Koch module_put(idev->owner); 324beafc54cSHans J. Koch } 325beafc54cSHans J. Koch if (filep->f_flags & FASYNC) 326beafc54cSHans J. Koch ret = uio_fasync(-1, filep, 0); 327beafc54cSHans J. Koch kfree(listener); 328beafc54cSHans J. Koch return ret; 329beafc54cSHans J. Koch } 330beafc54cSHans J. Koch 331beafc54cSHans J. Koch static unsigned int uio_poll(struct file *filep, poll_table *wait) 332beafc54cSHans J. Koch { 333beafc54cSHans J. Koch struct uio_listener *listener = filep->private_data; 334beafc54cSHans J. Koch struct uio_device *idev = listener->dev; 335beafc54cSHans J. Koch 336beafc54cSHans J. Koch if (idev->info->irq == UIO_IRQ_NONE) 337beafc54cSHans J. Koch return -EIO; 338beafc54cSHans J. Koch 339beafc54cSHans J. Koch poll_wait(filep, &idev->wait, wait); 340beafc54cSHans J. Koch if (listener->event_count != atomic_read(&idev->event)) 341beafc54cSHans J. Koch return POLLIN | POLLRDNORM; 342beafc54cSHans J. Koch return 0; 343beafc54cSHans J. Koch } 344beafc54cSHans J. Koch 345beafc54cSHans J. Koch static ssize_t uio_read(struct file *filep, char __user *buf, 346beafc54cSHans J. Koch size_t count, loff_t *ppos) 347beafc54cSHans J. Koch { 348beafc54cSHans J. Koch struct uio_listener *listener = filep->private_data; 349beafc54cSHans J. Koch struct uio_device *idev = listener->dev; 350beafc54cSHans J. Koch DECLARE_WAITQUEUE(wait, current); 351beafc54cSHans J. Koch ssize_t retval; 352beafc54cSHans J. Koch s32 event_count; 353beafc54cSHans J. Koch 354beafc54cSHans J. Koch if (idev->info->irq == UIO_IRQ_NONE) 355beafc54cSHans J. Koch return -EIO; 356beafc54cSHans J. Koch 357beafc54cSHans J. Koch if (count != sizeof(s32)) 358beafc54cSHans J. Koch return -EINVAL; 359beafc54cSHans J. Koch 360beafc54cSHans J. Koch add_wait_queue(&idev->wait, &wait); 361beafc54cSHans J. Koch 362beafc54cSHans J. Koch do { 363beafc54cSHans J. Koch set_current_state(TASK_INTERRUPTIBLE); 364beafc54cSHans J. Koch 365beafc54cSHans J. Koch event_count = atomic_read(&idev->event); 366beafc54cSHans J. Koch if (event_count != listener->event_count) { 367beafc54cSHans J. Koch if (copy_to_user(buf, &event_count, count)) 368beafc54cSHans J. Koch retval = -EFAULT; 369beafc54cSHans J. Koch else { 370beafc54cSHans J. Koch listener->event_count = event_count; 371beafc54cSHans J. Koch retval = count; 372beafc54cSHans J. Koch } 373beafc54cSHans J. Koch break; 374beafc54cSHans J. Koch } 375beafc54cSHans J. Koch 376beafc54cSHans J. Koch if (filep->f_flags & O_NONBLOCK) { 377beafc54cSHans J. Koch retval = -EAGAIN; 378beafc54cSHans J. Koch break; 379beafc54cSHans J. Koch } 380beafc54cSHans J. Koch 381beafc54cSHans J. Koch if (signal_pending(current)) { 382beafc54cSHans J. Koch retval = -ERESTARTSYS; 383beafc54cSHans J. Koch break; 384beafc54cSHans J. Koch } 385beafc54cSHans J. Koch schedule(); 386beafc54cSHans J. Koch } while (1); 387beafc54cSHans J. Koch 388beafc54cSHans J. Koch __set_current_state(TASK_RUNNING); 389beafc54cSHans J. Koch remove_wait_queue(&idev->wait, &wait); 390beafc54cSHans J. Koch 391beafc54cSHans J. Koch return retval; 392beafc54cSHans J. Koch } 393beafc54cSHans J. Koch 394beafc54cSHans J. Koch static int uio_find_mem_index(struct vm_area_struct *vma) 395beafc54cSHans J. Koch { 396beafc54cSHans J. Koch int mi; 397beafc54cSHans J. Koch struct uio_device *idev = vma->vm_private_data; 398beafc54cSHans J. Koch 399beafc54cSHans J. Koch for (mi = 0; mi < MAX_UIO_MAPS; mi++) { 400beafc54cSHans J. Koch if (idev->info->mem[mi].size == 0) 401beafc54cSHans J. Koch return -1; 402beafc54cSHans J. Koch if (vma->vm_pgoff == mi) 403beafc54cSHans J. Koch return mi; 404beafc54cSHans J. Koch } 405beafc54cSHans J. Koch return -1; 406beafc54cSHans J. Koch } 407beafc54cSHans J. Koch 408beafc54cSHans J. Koch static void uio_vma_open(struct vm_area_struct *vma) 409beafc54cSHans J. Koch { 410beafc54cSHans J. Koch struct uio_device *idev = vma->vm_private_data; 411beafc54cSHans J. Koch idev->vma_count++; 412beafc54cSHans J. Koch } 413beafc54cSHans J. Koch 414beafc54cSHans J. Koch static void uio_vma_close(struct vm_area_struct *vma) 415beafc54cSHans J. Koch { 416beafc54cSHans J. Koch struct uio_device *idev = vma->vm_private_data; 417beafc54cSHans J. Koch idev->vma_count--; 418beafc54cSHans J. Koch } 419beafc54cSHans J. Koch 420beafc54cSHans J. Koch static struct page *uio_vma_nopage(struct vm_area_struct *vma, 421beafc54cSHans J. Koch unsigned long address, int *type) 422beafc54cSHans J. Koch { 423beafc54cSHans J. Koch struct uio_device *idev = vma->vm_private_data; 424beafc54cSHans J. Koch struct page* page = NOPAGE_SIGBUS; 425beafc54cSHans J. Koch 426beafc54cSHans J. Koch int mi = uio_find_mem_index(vma); 427beafc54cSHans J. Koch if (mi < 0) 428beafc54cSHans J. Koch return page; 429beafc54cSHans J. Koch 430beafc54cSHans J. Koch if (idev->info->mem[mi].memtype == UIO_MEM_LOGICAL) 431beafc54cSHans J. Koch page = virt_to_page(idev->info->mem[mi].addr); 432beafc54cSHans J. Koch else 433beafc54cSHans J. Koch page = vmalloc_to_page((void*)idev->info->mem[mi].addr); 434beafc54cSHans J. Koch get_page(page); 435beafc54cSHans J. Koch if (type) 436beafc54cSHans J. Koch *type = VM_FAULT_MINOR; 437beafc54cSHans J. Koch return page; 438beafc54cSHans J. Koch } 439beafc54cSHans J. Koch 440beafc54cSHans J. Koch static struct vm_operations_struct uio_vm_ops = { 441beafc54cSHans J. Koch .open = uio_vma_open, 442beafc54cSHans J. Koch .close = uio_vma_close, 443beafc54cSHans J. Koch .nopage = uio_vma_nopage, 444beafc54cSHans J. Koch }; 445beafc54cSHans J. Koch 446beafc54cSHans J. Koch static int uio_mmap_physical(struct vm_area_struct *vma) 447beafc54cSHans J. Koch { 448beafc54cSHans J. Koch struct uio_device *idev = vma->vm_private_data; 449beafc54cSHans J. Koch int mi = uio_find_mem_index(vma); 450beafc54cSHans J. Koch if (mi < 0) 451beafc54cSHans J. Koch return -EINVAL; 452beafc54cSHans J. Koch 453beafc54cSHans J. Koch vma->vm_flags |= VM_IO | VM_RESERVED; 454beafc54cSHans J. Koch 455beafc54cSHans J. Koch return remap_pfn_range(vma, 456beafc54cSHans J. Koch vma->vm_start, 457beafc54cSHans J. Koch idev->info->mem[mi].addr >> PAGE_SHIFT, 458beafc54cSHans J. Koch vma->vm_end - vma->vm_start, 459beafc54cSHans J. Koch vma->vm_page_prot); 460beafc54cSHans J. Koch } 461beafc54cSHans J. Koch 462beafc54cSHans J. Koch static int uio_mmap_logical(struct vm_area_struct *vma) 463beafc54cSHans J. Koch { 464beafc54cSHans J. Koch vma->vm_flags |= VM_RESERVED; 465beafc54cSHans J. Koch vma->vm_ops = &uio_vm_ops; 466beafc54cSHans J. Koch uio_vma_open(vma); 467beafc54cSHans J. Koch return 0; 468beafc54cSHans J. Koch } 469beafc54cSHans J. Koch 470beafc54cSHans J. Koch static int uio_mmap(struct file *filep, struct vm_area_struct *vma) 471beafc54cSHans J. Koch { 472beafc54cSHans J. Koch struct uio_listener *listener = filep->private_data; 473beafc54cSHans J. Koch struct uio_device *idev = listener->dev; 474beafc54cSHans J. Koch int mi; 475beafc54cSHans J. Koch unsigned long requested_pages, actual_pages; 476beafc54cSHans J. Koch int ret = 0; 477beafc54cSHans J. Koch 478beafc54cSHans J. Koch if (vma->vm_end < vma->vm_start) 479beafc54cSHans J. Koch return -EINVAL; 480beafc54cSHans J. Koch 481beafc54cSHans J. Koch vma->vm_private_data = idev; 482beafc54cSHans J. Koch 483beafc54cSHans J. Koch mi = uio_find_mem_index(vma); 484beafc54cSHans J. Koch if (mi < 0) 485beafc54cSHans J. Koch return -EINVAL; 486beafc54cSHans J. Koch 487beafc54cSHans J. Koch requested_pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; 488beafc54cSHans J. Koch actual_pages = (idev->info->mem[mi].size + PAGE_SIZE -1) >> PAGE_SHIFT; 489beafc54cSHans J. Koch if (requested_pages > actual_pages) 490beafc54cSHans J. Koch return -EINVAL; 491beafc54cSHans J. Koch 492beafc54cSHans J. Koch if (idev->info->mmap) { 493beafc54cSHans J. Koch if (!try_module_get(idev->owner)) 494beafc54cSHans J. Koch return -ENODEV; 495beafc54cSHans J. Koch ret = idev->info->mmap(idev->info, vma); 496beafc54cSHans J. Koch module_put(idev->owner); 497beafc54cSHans J. Koch return ret; 498beafc54cSHans J. Koch } 499beafc54cSHans J. Koch 500beafc54cSHans J. Koch switch (idev->info->mem[mi].memtype) { 501beafc54cSHans J. Koch case UIO_MEM_PHYS: 502beafc54cSHans J. Koch return uio_mmap_physical(vma); 503beafc54cSHans J. Koch case UIO_MEM_LOGICAL: 504beafc54cSHans J. Koch case UIO_MEM_VIRTUAL: 505beafc54cSHans J. Koch return uio_mmap_logical(vma); 506beafc54cSHans J. Koch default: 507beafc54cSHans J. Koch return -EINVAL; 508beafc54cSHans J. Koch } 509beafc54cSHans J. Koch } 510beafc54cSHans J. Koch 511beafc54cSHans J. Koch static struct file_operations uio_fops = { 512beafc54cSHans J. Koch .owner = THIS_MODULE, 513beafc54cSHans J. Koch .open = uio_open, 514beafc54cSHans J. Koch .release = uio_release, 515beafc54cSHans J. Koch .read = uio_read, 516beafc54cSHans J. Koch .mmap = uio_mmap, 517beafc54cSHans J. Koch .poll = uio_poll, 518beafc54cSHans J. Koch .fasync = uio_fasync, 519beafc54cSHans J. Koch }; 520beafc54cSHans J. Koch 521beafc54cSHans J. Koch static int uio_major_init(void) 522beafc54cSHans J. Koch { 523beafc54cSHans J. Koch uio_major = register_chrdev(0, "uio", &uio_fops); 524beafc54cSHans J. Koch if (uio_major < 0) 525beafc54cSHans J. Koch return uio_major; 526beafc54cSHans J. Koch return 0; 527beafc54cSHans J. Koch } 528beafc54cSHans J. Koch 529beafc54cSHans J. Koch static void uio_major_cleanup(void) 530beafc54cSHans J. Koch { 531beafc54cSHans J. Koch unregister_chrdev(uio_major, "uio"); 532beafc54cSHans J. Koch } 533beafc54cSHans J. Koch 534beafc54cSHans J. Koch static int init_uio_class(void) 535beafc54cSHans J. Koch { 536beafc54cSHans J. Koch int ret = 0; 537beafc54cSHans J. Koch 538beafc54cSHans J. Koch if (uio_class != NULL) { 539beafc54cSHans J. Koch kref_get(&uio_class->kref); 540beafc54cSHans J. Koch goto exit; 541beafc54cSHans J. Koch } 542beafc54cSHans J. Koch 543beafc54cSHans J. Koch /* This is the first time in here, set everything up properly */ 544beafc54cSHans J. Koch ret = uio_major_init(); 545beafc54cSHans J. Koch if (ret) 546beafc54cSHans J. Koch goto exit; 547beafc54cSHans J. Koch 548beafc54cSHans J. Koch uio_class = kzalloc(sizeof(*uio_class), GFP_KERNEL); 549beafc54cSHans J. Koch if (!uio_class) { 550beafc54cSHans J. Koch ret = -ENOMEM; 551beafc54cSHans J. Koch goto err_kzalloc; 552beafc54cSHans J. Koch } 553beafc54cSHans J. Koch 554beafc54cSHans J. Koch kref_init(&uio_class->kref); 555beafc54cSHans J. Koch uio_class->class = class_create(THIS_MODULE, "uio"); 556beafc54cSHans J. Koch if (IS_ERR(uio_class->class)) { 557beafc54cSHans J. Koch ret = IS_ERR(uio_class->class); 558beafc54cSHans J. Koch printk(KERN_ERR "class_create failed for uio\n"); 559beafc54cSHans J. Koch goto err_class_create; 560beafc54cSHans J. Koch } 561beafc54cSHans J. Koch return 0; 562beafc54cSHans J. Koch 563beafc54cSHans J. Koch err_class_create: 564beafc54cSHans J. Koch kfree(uio_class); 565beafc54cSHans J. Koch uio_class = NULL; 566beafc54cSHans J. Koch err_kzalloc: 567beafc54cSHans J. Koch uio_major_cleanup(); 568beafc54cSHans J. Koch exit: 569beafc54cSHans J. Koch return ret; 570beafc54cSHans J. Koch } 571beafc54cSHans J. Koch 572beafc54cSHans J. Koch static void release_uio_class(struct kref *kref) 573beafc54cSHans J. Koch { 574beafc54cSHans J. Koch /* Ok, we cheat as we know we only have one uio_class */ 575beafc54cSHans J. Koch class_destroy(uio_class->class); 576beafc54cSHans J. Koch kfree(uio_class); 577beafc54cSHans J. Koch uio_major_cleanup(); 578beafc54cSHans J. Koch uio_class = NULL; 579beafc54cSHans J. Koch } 580beafc54cSHans J. Koch 581beafc54cSHans J. Koch static void uio_class_destroy(void) 582beafc54cSHans J. Koch { 583beafc54cSHans J. Koch if (uio_class) 584beafc54cSHans J. Koch kref_put(&uio_class->kref, release_uio_class); 585beafc54cSHans J. Koch } 586beafc54cSHans J. Koch 587beafc54cSHans J. Koch /** 588beafc54cSHans J. Koch * uio_register_device - register a new userspace IO device 589beafc54cSHans J. Koch * @owner: module that creates the new device 590beafc54cSHans J. Koch * @parent: parent device 591beafc54cSHans J. Koch * @info: UIO device capabilities 592beafc54cSHans J. Koch * 593beafc54cSHans J. Koch * returns zero on success or a negative error code. 594beafc54cSHans J. Koch */ 595beafc54cSHans J. Koch int __uio_register_device(struct module *owner, 596beafc54cSHans J. Koch struct device *parent, 597beafc54cSHans J. Koch struct uio_info *info) 598beafc54cSHans J. Koch { 599beafc54cSHans J. Koch struct uio_device *idev; 600beafc54cSHans J. Koch int ret = 0; 601beafc54cSHans J. Koch 602beafc54cSHans J. Koch if (!parent || !info || !info->name || !info->version) 603beafc54cSHans J. Koch return -EINVAL; 604beafc54cSHans J. Koch 605beafc54cSHans J. Koch info->uio_dev = NULL; 606beafc54cSHans J. Koch 607beafc54cSHans J. Koch ret = init_uio_class(); 608beafc54cSHans J. Koch if (ret) 609beafc54cSHans J. Koch return ret; 610beafc54cSHans J. Koch 611beafc54cSHans J. Koch idev = kzalloc(sizeof(*idev), GFP_KERNEL); 612beafc54cSHans J. Koch if (!idev) { 613beafc54cSHans J. Koch ret = -ENOMEM; 614beafc54cSHans J. Koch goto err_kzalloc; 615beafc54cSHans J. Koch } 616beafc54cSHans J. Koch 617beafc54cSHans J. Koch idev->owner = owner; 618beafc54cSHans J. Koch idev->info = info; 619beafc54cSHans J. Koch init_waitqueue_head(&idev->wait); 620beafc54cSHans J. Koch atomic_set(&idev->event, 0); 621beafc54cSHans J. Koch 622beafc54cSHans J. Koch ret = uio_get_minor(idev); 623beafc54cSHans J. Koch if (ret) 624beafc54cSHans J. Koch goto err_get_minor; 625beafc54cSHans J. Koch 626beafc54cSHans J. Koch idev->dev = device_create(uio_class->class, parent, 627beafc54cSHans J. Koch MKDEV(uio_major, idev->minor), 628beafc54cSHans J. Koch "uio%d", idev->minor); 629beafc54cSHans J. Koch if (IS_ERR(idev->dev)) { 630beafc54cSHans J. Koch printk(KERN_ERR "UIO: device register failed\n"); 631beafc54cSHans J. Koch ret = PTR_ERR(idev->dev); 632beafc54cSHans J. Koch goto err_device_create; 633beafc54cSHans J. Koch } 634beafc54cSHans J. Koch dev_set_drvdata(idev->dev, idev); 635beafc54cSHans J. Koch 636beafc54cSHans J. Koch ret = uio_dev_add_attributes(idev); 637beafc54cSHans J. Koch if (ret) 638beafc54cSHans J. Koch goto err_uio_dev_add_attributes; 639beafc54cSHans J. Koch 640beafc54cSHans J. Koch info->uio_dev = idev; 641beafc54cSHans J. Koch 642beafc54cSHans J. Koch if (idev->info->irq >= 0) { 643beafc54cSHans J. Koch ret = request_irq(idev->info->irq, uio_interrupt, 644beafc54cSHans J. Koch idev->info->irq_flags, idev->info->name, idev); 645beafc54cSHans J. Koch if (ret) 646beafc54cSHans J. Koch goto err_request_irq; 647beafc54cSHans J. Koch } 648beafc54cSHans J. Koch 649beafc54cSHans J. Koch return 0; 650beafc54cSHans J. Koch 651beafc54cSHans J. Koch err_request_irq: 652beafc54cSHans J. Koch uio_dev_del_attributes(idev); 653beafc54cSHans J. Koch err_uio_dev_add_attributes: 654beafc54cSHans J. Koch device_destroy(uio_class->class, MKDEV(uio_major, idev->minor)); 655beafc54cSHans J. Koch err_device_create: 656beafc54cSHans J. Koch uio_free_minor(idev); 657beafc54cSHans J. Koch err_get_minor: 658beafc54cSHans J. Koch kfree(idev); 659beafc54cSHans J. Koch err_kzalloc: 660beafc54cSHans J. Koch uio_class_destroy(); 661beafc54cSHans J. Koch return ret; 662beafc54cSHans J. Koch } 663beafc54cSHans J. Koch EXPORT_SYMBOL_GPL(__uio_register_device); 664beafc54cSHans J. Koch 665beafc54cSHans J. Koch /** 666beafc54cSHans J. Koch * uio_unregister_device - unregister a industrial IO device 667beafc54cSHans J. Koch * @info: UIO device capabilities 668beafc54cSHans J. Koch * 669beafc54cSHans J. Koch */ 670beafc54cSHans J. Koch void uio_unregister_device(struct uio_info *info) 671beafc54cSHans J. Koch { 672beafc54cSHans J. Koch struct uio_device *idev; 673beafc54cSHans J. Koch 674beafc54cSHans J. Koch if (!info || !info->uio_dev) 675beafc54cSHans J. Koch return; 676beafc54cSHans J. Koch 677beafc54cSHans J. Koch idev = info->uio_dev; 678beafc54cSHans J. Koch 679beafc54cSHans J. Koch uio_free_minor(idev); 680beafc54cSHans J. Koch 681beafc54cSHans J. Koch if (info->irq >= 0) 682beafc54cSHans J. Koch free_irq(info->irq, idev); 683beafc54cSHans J. Koch 684beafc54cSHans J. Koch uio_dev_del_attributes(idev); 685beafc54cSHans J. Koch 686beafc54cSHans J. Koch dev_set_drvdata(idev->dev, NULL); 687beafc54cSHans J. Koch device_destroy(uio_class->class, MKDEV(uio_major, idev->minor)); 688beafc54cSHans J. Koch kfree(idev); 689beafc54cSHans J. Koch uio_class_destroy(); 690beafc54cSHans J. Koch 691beafc54cSHans J. Koch return; 692beafc54cSHans J. Koch } 693beafc54cSHans J. Koch EXPORT_SYMBOL_GPL(uio_unregister_device); 694beafc54cSHans J. Koch 695beafc54cSHans J. Koch static int __init uio_init(void) 696beafc54cSHans J. Koch { 697beafc54cSHans J. Koch return 0; 698beafc54cSHans J. Koch } 699beafc54cSHans J. Koch 700beafc54cSHans J. Koch static void __exit uio_exit(void) 701beafc54cSHans J. Koch { 702beafc54cSHans J. Koch } 703beafc54cSHans J. Koch 704beafc54cSHans J. Koch module_init(uio_init) 705beafc54cSHans J. Koch module_exit(uio_exit) 706beafc54cSHans J. Koch MODULE_LICENSE("GPL v2"); 707