litmus-rt.git - The LITMUS^RT kernel.

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author	Randy Dunlap <randy.dunlap@oracle.com>	2008-02-29 17:21:53 -0500
committer	Sam Ravnborg <sam@ravnborg.org>	2009-01-02 14:43:25 -0500
commit	2af238e455ef5fd31c2f7a06c2db3f13d843b9bf (patch)
tree	9a1da45a4b81a03f25742a57843228362ca66fc5 /net/lapb/lapb_subr.c
parent	80a7d1d991e35b0370c0396f36f6a076869a6bac (diff)

kbuild: make *config usage docs

Create a kconfig user assistance guide, with a few tips and hints about using menuconfig, xconfig, and gconfig. Mostly contains user interface, environment variables, and search topics, along with mini.config/custom.config usage. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

Diffstat (limited to 'net/lapb/lapb_subr.c')

0 files changed, 0 insertions, 0 deletions

/* * drivers/uio/uio.c * * Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de> * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de> * Copyright(C) 2006, Hans J. Koch <hjk@linutronix.de> * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com> * * Userspace IO * * Base Functions * * Licensed under the GPLv2 only. */ #include <linux/module.h> #include <linux/init.h> #include <linux/poll.h> #include <linux/device.h> #include <linux/mm.h> #include <linux/idr.h> #include <linux/string.h> #include <linux/kobject.h> #include <linux/uio_driver.h> #define UIO_MAX_DEVICES 255 struct uio_device { struct module *owner; struct device *dev; int minor; atomic_t event; struct fasync_struct *async_queue; wait_queue_head_t wait; int vma_count; struct uio_info *info; struct kset map_attr_kset; }; static int uio_major; static DEFINE_IDR(uio_idr); static struct file_operations uio_fops; /* UIO class infrastructure */ static struct uio_class { struct kref kref; struct class *class; } *uio_class; /* * attributes */ static struct attribute attr_addr = { .name = "addr", .mode = S_IRUGO, }; static struct attribute attr_size = { .name = "size", .mode = S_IRUGO, }; static struct attribute* map_attrs[] = { &attr_addr, &attr_size, NULL }; static ssize_t map_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) { struct uio_mem *mem = container_of(kobj, struct uio_mem, kobj); if (strncmp(attr->name,"addr",4) == 0) return sprintf(buf, "0x%lx\n", mem->addr); if (strncmp(attr->name,"size",4) == 0) return sprintf(buf, "0x%lx\n", mem->size); return -ENODEV; } static void map_attr_release(struct kobject *kobj) { /* TODO ??? */ } static struct sysfs_ops map_attr_ops = { .show = map_attr_show, }; static struct kobj_type map_attr_type = { .release = map_attr_release, .sysfs_ops = &map_attr_ops, .default_attrs = map_attrs, }; static ssize_t show_name(struct device *dev, struct device_attribute *attr, char *buf) { struct uio_device *idev = dev_get_drvdata(dev); if (idev) return sprintf(buf, "%s\n", idev->info->name); else return -ENODEV; } static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); static ssize_t show_version(struct device *dev, struct device_attribute *attr, char *buf) { struct uio_device *idev = dev_get_drvdata(dev); if (idev) return sprintf(buf, "%s\n", idev->info->version); else return -ENODEV; } static DEVICE_ATTR(version, S_IRUGO, show_version, NULL); static ssize_t show_event(struct device *dev, struct device_attribute *attr, char *buf) { struct uio_device *idev = dev_get_drvdata(dev); if (idev) return sprintf(buf, "%u\n", (unsigned int)atomic_read(&idev->event)); else return -ENODEV; } static DEVICE_ATTR(event, S_IRUGO, show_event, NULL); static struct attribute *uio_attrs[] = { &dev_attr_name.attr, &dev_attr_version.attr, &dev_attr_event.attr, NULL, }; static struct attribute_group uio_attr_grp = { .attrs = uio_attrs, }; /* * device functions */ static int uio_dev_add_attributes(struct uio_device *idev) { int ret; int mi; int map_found = 0; struct uio_mem *mem; ret = sysfs_create_group(&idev->dev->kobj, &uio_attr_grp); if (ret) goto err_group; for (mi = 0; mi < MAX_UIO_MAPS; mi++) { mem = &idev->info->mem[mi]; if (mem->size == 0) break; if (!map_found) { map_found = 1; kobject_set_name(&idev->map_attr_kset.kobj,"maps"); idev->map_attr_kset.ktype = &map_attr_type; idev->map_attr_kset.kobj.parent = &idev->dev->kobj; ret = kset_register(&idev->map_attr_kset); if (ret) goto err_remove_group; } kobject_init(&mem->kobj); kobject_set_name(&mem->kobj,"map%d",mi); mem->kobj.parent = &idev->map_attr_kset.kobj; mem->kobj.kset = &idev->map_attr_kset; ret = kobject_add(&mem->kobj); if (ret) goto err_remove_maps; } return 0; err_remove_maps: for (mi--; mi>=0; mi--) { mem = &idev->info->mem[mi]; kobject_unregister(&mem->kobj); } kset_unregister(&idev->map_attr_kset); /* Needed ? */ err_remove_group: sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp); err_group: dev_err(idev->dev, "error creating sysfs files (%d)\n", ret); return ret; } static void uio_dev_del_attributes(struct uio_device *idev) { int mi; struct uio_mem *mem; for (mi = 0; mi < MAX_UIO_MAPS; mi++) { mem = &idev->info->mem[mi]; if (mem->size == 0) break; kobject_unregister(&mem->kobj); } kset_unregister(&idev->map_attr_kset); sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp); } static int uio_get_minor(struct uio_device *idev) { static DEFINE_MUTEX(minor_lock); int retval = -ENOMEM; int id; mutex_lock(&minor_lock); if (idr_pre_get(&uio_idr, GFP_KERNEL) == 0) goto exit; retval = idr_get_new(&uio_idr, idev, &id); if (retval < 0) { if (retval == -EAGAIN) retval = -ENOMEM; goto exit; } idev->minor = id & MAX_ID_MASK; exit: mutex_unlock(&minor_lock); return retval; } static void uio_free_minor(struct uio_device *idev) { idr_remove(&uio_idr, idev->minor); } /** * uio_event_notify - trigger an interrupt event * @info: UIO device capabilities */ void uio_event_notify(struct uio_info *info) { struct uio_device *idev = info->uio_dev; atomic_inc(&idev->event); wake_up_interruptible(&idev->wait); kill_fasync(&idev->async_queue, SIGIO, POLL_IN); } EXPORT_SYMBOL_GPL(uio_event_notify); /** * uio_interrupt - hardware interrupt handler * @irq: IRQ number, can be UIO_IRQ_CYCLIC for cyclic timer * @dev_id: Pointer to the devices uio_device structure */ static irqreturn_t uio_interrupt(int irq, void *dev_id) { struct uio_device *idev = (struct uio_device *)dev_id; irqreturn_t ret = idev->info->handler(irq, idev->info); if (ret == IRQ_HANDLED) uio_event_notify(idev->info); return ret; } struct uio_listener { struct uio_device *dev; s32 event_count; }; static int uio_open(struct inode *inode, struct file *filep) { struct uio_device *idev; struct uio_listener *listener; int ret = 0; idev = idr_find(&uio_idr, iminor(inode)); if (!idev) return -ENODEV; listener = kmalloc(sizeof(*listener), GFP_KERNEL); if (!listener) return -ENOMEM; listener->dev = idev; listener->event_count = atomic_read(&idev->event); filep->private_data = listener; if (idev->info->open) { if (!try_module_get(idev->owner)) return -ENODEV; ret = idev->info->open(idev->info, inode); module_put(idev->owner); } if (ret) kfree(listener); return ret; } static int uio_fasync(int fd, struct file *filep, int on) { struct uio_listener *listener = filep->private_data; struct uio_device *idev = listener->dev; return fasync_helper(fd, filep, on, &idev->async_queue); } static int uio_release(struct inode *inode, struct file *filep) { int ret = 0; struct uio_listener *listener = filep->private_data; struct uio_device *idev = listener->dev; if (idev->info->release) { if (!try_module_get(idev->owner)) return -ENODEV; ret = idev->info->release(idev->info, inode); module_put(idev->owner); } if (filep->f_flags & FASYNC) ret = uio_fasync(-1, filep, 0); kfree(listener); return ret; } static unsigned int uio_poll(struct file *filep, poll_table *wait) { struct uio_listener *listener = filep->private_data; struct uio_device *idev = listener->dev; if (idev->info->irq == UIO_IRQ_NONE) return -EIO; poll_wait(filep, &idev->wait, wait); if (listener->event_count != atomic_read(&idev->event)) return POLLIN | POLLRDNORM; return 0; } static ssize_t uio_read(struct file *filep, char __user *buf, size_t count, loff_t *ppos) { struct uio_listener *listener = filep->private_data; struct uio_device *idev = listener->dev; DECLARE_WAITQUEUE(wait, current); ssize_t retval; s32 event_count; if (idev->info->irq == UIO_IRQ_NONE) return -EIO; if (count != sizeof(s32)) return -EINVAL; add_wait_queue(&idev->wait, &wait); do { set_current_state(TASK_INTERRUPTIBLE); event_count = atomic_read(&idev->event); if (event_count != listener->event_count) { if (copy_to_user(buf, &event_count, count)) retval = -EFAULT; else { listener->event_count = event_count; retval = count; } break; } if (filep->f_flags & O_NONBLOCK) { retval = -EAGAIN; break; } if (signal_pending(current)) { retval = -ERESTARTSYS; break; } schedule(); } while (1); __set_current_state(TASK_RUNNING); remove_wait_queue(&idev->wait, &wait); return retval;


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