mirror of https://gitee.com/openkylin/linux.git
UIO: Add the User IO core code
This interface allows the ability to write the majority of a driver in userspace with only a very small shell of a driver in the kernel itself. It uses a char device and sysfs to interact with a userspace process to process interrupts and control memory accesses. See the docbook documentation for more details on how to use this interface. From: Hans J. Koch <hjk@linutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benedikt Spranger <b.spranger@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Hans J. Koch
Greg Kroah-Hartman
parent
5bae7ac9fe
commit
beafc54c4e
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@ -84,4 +84,5 @@ source "drivers/auxdisplay/Kconfig"
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source "drivers/kvm/Kconfig"
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source "drivers/uio/Kconfig"
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endmenu
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@ -40,6 +40,7 @@ obj-$(CONFIG_ATA) += ata/
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obj-$(CONFIG_FUSION) += message/
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obj-$(CONFIG_FIREWIRE) += firewire/
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obj-$(CONFIG_IEEE1394) += ieee1394/
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obj-$(CONFIG_UIO) += uio/
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obj-y += cdrom/
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obj-y += auxdisplay/
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obj-$(CONFIG_MTD) += mtd/
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@ -0,0 +1,16 @@
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menu "Userspace I/O"
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depends on !S390
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config UIO
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tristate "Userspace I/O drivers"
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default n
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help
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Enable this to allow the userspace driver core code to be
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built. This code allows userspace programs easy access to
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kernel interrupts and memory locations, allowing some drivers
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to be written in userspace. Note that a small kernel driver
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is also required for interrupt handling to work properly.
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If you don't know what to do here, say N.
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endmenu
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@ -0,0 +1 @@
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obj-$(CONFIG_UIO) += uio.o
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@ -0,0 +1,701 @@
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/*
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* drivers/uio/uio.c
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*
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* Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de>
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* Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
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* Copyright(C) 2006, Hans J. Koch <hjk@linutronix.de>
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* Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com>
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*
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* Userspace IO
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*
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* Base Functions
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*
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* Licensed under the GPLv2 only.
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*/
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/poll.h>
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#include <linux/device.h>
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#include <linux/mm.h>
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#include <linux/idr.h>
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#include <linux/string.h>
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#include <linux/kobject.h>
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#include <linux/uio_driver.h>
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#define UIO_MAX_DEVICES 255
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struct uio_device {
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struct module *owner;
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struct device *dev;
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int minor;
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atomic_t event;
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struct fasync_struct *async_queue;
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wait_queue_head_t wait;
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int vma_count;
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struct uio_info *info;
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struct kset map_attr_kset;
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};
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static int uio_major;
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static DEFINE_IDR(uio_idr);
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static struct file_operations uio_fops;
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/* UIO class infrastructure */
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static struct uio_class {
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struct kref kref;
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struct class *class;
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} *uio_class;
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/*
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* attributes
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*/
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static struct attribute attr_addr = {
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.name = "addr",
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.mode = S_IRUGO,
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};
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static struct attribute attr_size = {
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.name = "size",
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.mode = S_IRUGO,
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};
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static struct attribute* map_attrs[] = {
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&attr_addr, &attr_size, NULL
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};
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static ssize_t map_attr_show(struct kobject *kobj, struct attribute *attr,
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char *buf)
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{
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struct uio_mem *mem = container_of(kobj, struct uio_mem, kobj);
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if (strncmp(attr->name,"addr",4) == 0)
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return sprintf(buf, "0x%lx\n", mem->addr);
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if (strncmp(attr->name,"size",4) == 0)
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return sprintf(buf, "0x%lx\n", mem->size);
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return -ENODEV;
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}
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static void map_attr_release(struct kobject *kobj)
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{
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/* TODO ??? */
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}
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static struct sysfs_ops map_attr_ops = {
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.show = map_attr_show,
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};
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static struct kobj_type map_attr_type = {
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.release = map_attr_release,
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.sysfs_ops = &map_attr_ops,
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.default_attrs = map_attrs,
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};
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static ssize_t show_name(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct uio_device *idev = dev_get_drvdata(dev);
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if (idev)
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return sprintf(buf, "%s\n", idev->info->name);
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else
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return -ENODEV;
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}
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static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
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static ssize_t show_version(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct uio_device *idev = dev_get_drvdata(dev);
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if (idev)
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return sprintf(buf, "%s\n", idev->info->version);
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else
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return -ENODEV;
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}
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static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
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static ssize_t show_event(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct uio_device *idev = dev_get_drvdata(dev);
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if (idev)
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return sprintf(buf, "%u\n",
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(unsigned int)atomic_read(&idev->event));
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else
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return -ENODEV;
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}
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static DEVICE_ATTR(event, S_IRUGO, show_event, NULL);
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static struct attribute *uio_attrs[] = {
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&dev_attr_name.attr,
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&dev_attr_version.attr,
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&dev_attr_event.attr,
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NULL,
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};
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static struct attribute_group uio_attr_grp = {
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.attrs = uio_attrs,
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};
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/*
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* device functions
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*/
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static int uio_dev_add_attributes(struct uio_device *idev)
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{
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int ret;
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int mi;
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int map_found = 0;
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struct uio_mem *mem;
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ret = sysfs_create_group(&idev->dev->kobj, &uio_attr_grp);
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if (ret)
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goto err_group;
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for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
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mem = &idev->info->mem[mi];
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if (mem->size == 0)
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break;
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if (!map_found) {
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map_found = 1;
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kobject_set_name(&idev->map_attr_kset.kobj,"maps");
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idev->map_attr_kset.ktype = &map_attr_type;
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idev->map_attr_kset.kobj.parent = &idev->dev->kobj;
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ret = kset_register(&idev->map_attr_kset);
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if (ret)
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goto err_remove_group;
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}
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kobject_init(&mem->kobj);
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kobject_set_name(&mem->kobj,"map%d",mi);
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mem->kobj.parent = &idev->map_attr_kset.kobj;
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mem->kobj.kset = &idev->map_attr_kset;
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ret = kobject_add(&mem->kobj);
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if (ret)
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goto err_remove_maps;
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}
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return 0;
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err_remove_maps:
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for (mi--; mi>=0; mi--) {
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mem = &idev->info->mem[mi];
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kobject_unregister(&mem->kobj);
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}
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kset_unregister(&idev->map_attr_kset); /* Needed ? */
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err_remove_group:
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sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp);
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err_group:
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dev_err(idev->dev, "error creating sysfs files (%d)\n", ret);
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return ret;
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}
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static void uio_dev_del_attributes(struct uio_device *idev)
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{
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int mi;
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struct uio_mem *mem;
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for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
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mem = &idev->info->mem[mi];
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if (mem->size == 0)
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break;
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kobject_unregister(&mem->kobj);
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}
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kset_unregister(&idev->map_attr_kset);
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sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp);
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}
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static int uio_get_minor(struct uio_device *idev)
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{
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static DEFINE_MUTEX(minor_lock);
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int retval = -ENOMEM;
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int id;
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mutex_lock(&minor_lock);
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if (idr_pre_get(&uio_idr, GFP_KERNEL) == 0)
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goto exit;
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retval = idr_get_new(&uio_idr, idev, &id);
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if (retval < 0) {
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if (retval == -EAGAIN)
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retval = -ENOMEM;
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goto exit;
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}
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idev->minor = id & MAX_ID_MASK;
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exit:
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mutex_unlock(&minor_lock);
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return retval;
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}
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static void uio_free_minor(struct uio_device *idev)
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{
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idr_remove(&uio_idr, idev->minor);
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}
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/**
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* uio_event_notify - trigger an interrupt event
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* @info: UIO device capabilities
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*/
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void uio_event_notify(struct uio_info *info)
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{
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struct uio_device *idev = info->uio_dev;
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atomic_inc(&idev->event);
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wake_up_interruptible(&idev->wait);
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kill_fasync(&idev->async_queue, SIGIO, POLL_IN);
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}
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EXPORT_SYMBOL_GPL(uio_event_notify);
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/**
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* uio_interrupt - hardware interrupt handler
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* @irq: IRQ number, can be UIO_IRQ_CYCLIC for cyclic timer
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* @dev_id: Pointer to the devices uio_device structure
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*/
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static irqreturn_t uio_interrupt(int irq, void *dev_id)
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{
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struct uio_device *idev = (struct uio_device *)dev_id;
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irqreturn_t ret = idev->info->handler(irq, idev->info);
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if (ret == IRQ_HANDLED)
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uio_event_notify(idev->info);
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return ret;
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}
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struct uio_listener {
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struct uio_device *dev;
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s32 event_count;
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};
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static int uio_open(struct inode *inode, struct file *filep)
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{
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struct uio_device *idev;
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struct uio_listener *listener;
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int ret = 0;
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idev = idr_find(&uio_idr, iminor(inode));
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if (!idev)
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return -ENODEV;
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listener = kmalloc(sizeof(*listener), GFP_KERNEL);
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if (!listener)
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return -ENOMEM;
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listener->dev = idev;
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listener->event_count = atomic_read(&idev->event);
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filep->private_data = listener;
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if (idev->info->open) {
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if (!try_module_get(idev->owner))
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return -ENODEV;
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ret = idev->info->open(idev->info, inode);
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module_put(idev->owner);
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}
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if (ret)
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kfree(listener);
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return ret;
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}
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static int uio_fasync(int fd, struct file *filep, int on)
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{
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struct uio_listener *listener = filep->private_data;
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struct uio_device *idev = listener->dev;
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return fasync_helper(fd, filep, on, &idev->async_queue);
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}
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static int uio_release(struct inode *inode, struct file *filep)
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{
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int ret = 0;
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struct uio_listener *listener = filep->private_data;
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struct uio_device *idev = listener->dev;
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if (idev->info->release) {
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if (!try_module_get(idev->owner))
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return -ENODEV;
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ret = idev->info->release(idev->info, inode);
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module_put(idev->owner);
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}
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if (filep->f_flags & FASYNC)
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ret = uio_fasync(-1, filep, 0);
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kfree(listener);
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return ret;
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}
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static unsigned int uio_poll(struct file *filep, poll_table *wait)
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{
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struct uio_listener *listener = filep->private_data;
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struct uio_device *idev = listener->dev;
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if (idev->info->irq == UIO_IRQ_NONE)
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return -EIO;
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poll_wait(filep, &idev->wait, wait);
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if (listener->event_count != atomic_read(&idev->event))
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return POLLIN | POLLRDNORM;
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return 0;
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}
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static ssize_t uio_read(struct file *filep, char __user *buf,
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size_t count, loff_t *ppos)
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{
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struct uio_listener *listener = filep->private_data;
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struct uio_device *idev = listener->dev;
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DECLARE_WAITQUEUE(wait, current);
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ssize_t retval;
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s32 event_count;
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if (idev->info->irq == UIO_IRQ_NONE)
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return -EIO;
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if (count != sizeof(s32))
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return -EINVAL;
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add_wait_queue(&idev->wait, &wait);
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do {
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set_current_state(TASK_INTERRUPTIBLE);
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event_count = atomic_read(&idev->event);
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if (event_count != listener->event_count) {
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if (copy_to_user(buf, &event_count, count))
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retval = -EFAULT;
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else {
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listener->event_count = event_count;
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retval = count;
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}
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break;
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}
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if (filep->f_flags & O_NONBLOCK) {
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retval = -EAGAIN;
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break;
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}
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if (signal_pending(current)) {
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retval = -ERESTARTSYS;
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break;
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}
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schedule();
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} while (1);
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__set_current_state(TASK_RUNNING);
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remove_wait_queue(&idev->wait, &wait);
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return retval;
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}
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static int uio_find_mem_index(struct vm_area_struct *vma)
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{
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int mi;
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struct uio_device *idev = vma->vm_private_data;
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for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
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if (idev->info->mem[mi].size == 0)
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return -1;
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if (vma->vm_pgoff == mi)
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return mi;
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}
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return -1;
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}
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static void uio_vma_open(struct vm_area_struct *vma)
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{
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struct uio_device *idev = vma->vm_private_data;
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idev->vma_count++;
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}
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static void uio_vma_close(struct vm_area_struct *vma)
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{
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struct uio_device *idev = vma->vm_private_data;
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idev->vma_count--;
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}
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static struct page *uio_vma_nopage(struct vm_area_struct *vma,
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unsigned long address, int *type)
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{
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struct uio_device *idev = vma->vm_private_data;
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struct page* page = NOPAGE_SIGBUS;
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int mi = uio_find_mem_index(vma);
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if (mi < 0)
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return page;
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if (idev->info->mem[mi].memtype == UIO_MEM_LOGICAL)
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page = virt_to_page(idev->info->mem[mi].addr);
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else
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page = vmalloc_to_page((void*)idev->info->mem[mi].addr);
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get_page(page);
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if (type)
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*type = VM_FAULT_MINOR;
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return page;
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}
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static struct vm_operations_struct uio_vm_ops = {
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.open = uio_vma_open,
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.close = uio_vma_close,
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.nopage = uio_vma_nopage,
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};
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static int uio_mmap_physical(struct vm_area_struct *vma)
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{
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struct uio_device *idev = vma->vm_private_data;
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int mi = uio_find_mem_index(vma);
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if (mi < 0)
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return -EINVAL;
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vma->vm_flags |= VM_IO | VM_RESERVED;
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return remap_pfn_range(vma,
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vma->vm_start,
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idev->info->mem[mi].addr >> PAGE_SHIFT,
|
||||
vma->vm_end - vma->vm_start,
|
||||
vma->vm_page_prot);
|
||||
}
|
||||
|
||||
static int uio_mmap_logical(struct vm_area_struct *vma)
|
||||
{
|
||||
vma->vm_flags |= VM_RESERVED;
|
||||
vma->vm_ops = &uio_vm_ops;
|
||||
uio_vma_open(vma);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int uio_mmap(struct file *filep, struct vm_area_struct *vma)
|
||||
{
|
||||
struct uio_listener *listener = filep->private_data;
|
||||
struct uio_device *idev = listener->dev;
|
||||
int mi;
|
||||
unsigned long requested_pages, actual_pages;
|
||||
int ret = 0;
|
||||
|
||||
if (vma->vm_end < vma->vm_start)
|
||||
return -EINVAL;
|
||||
|
||||
vma->vm_private_data = idev;
|
||||
|
||||
mi = uio_find_mem_index(vma);
|
||||
if (mi < 0)
|
||||
return -EINVAL;
|
||||
|
||||
requested_pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
|
||||
actual_pages = (idev->info->mem[mi].size + PAGE_SIZE -1) >> PAGE_SHIFT;
|
||||
if (requested_pages > actual_pages)
|
||||
return -EINVAL;
|
||||
|
||||
if (idev->info->mmap) {
|
||||
if (!try_module_get(idev->owner))
|
||||
return -ENODEV;
|
||||
ret = idev->info->mmap(idev->info, vma);
|
||||
module_put(idev->owner);
|
||||
return ret;
|
||||
}
|
||||
|
||||
switch (idev->info->mem[mi].memtype) {
|
||||
case UIO_MEM_PHYS:
|
||||
return uio_mmap_physical(vma);
|
||||
case UIO_MEM_LOGICAL:
|
||||
case UIO_MEM_VIRTUAL:
|
||||
return uio_mmap_logical(vma);
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
}
|
||||
|
||||
static struct file_operations uio_fops = {
|
||||
.owner = THIS_MODULE,
|
||||
.open = uio_open,
|
||||
.release = uio_release,
|
||||
.read = uio_read,
|
||||
.mmap = uio_mmap,
|
||||
.poll = uio_poll,
|
||||
.fasync = uio_fasync,
|
||||
};
|
||||
|
||||
static int uio_major_init(void)
|
||||
{
|
||||
uio_major = register_chrdev(0, "uio", &uio_fops);
|
||||
if (uio_major < 0)
|
||||
return uio_major;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void uio_major_cleanup(void)
|
||||
{
|
||||
unregister_chrdev(uio_major, "uio");
|
||||
}
|
||||
|
||||
static int init_uio_class(void)
|
||||
{
|
||||
int ret = 0;
|
||||
|
||||
if (uio_class != NULL) {
|
||||
kref_get(&uio_class->kref);
|
||||
goto exit;
|
||||
}
|
||||
|
||||
/* This is the first time in here, set everything up properly */
|
||||
ret = uio_major_init();
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
uio_class = kzalloc(sizeof(*uio_class), GFP_KERNEL);
|
||||
if (!uio_class) {
|
||||
ret = -ENOMEM;
|
||||
goto err_kzalloc;
|
||||
}
|
||||
|
||||
kref_init(&uio_class->kref);
|
||||
uio_class->class = class_create(THIS_MODULE, "uio");
|
||||
if (IS_ERR(uio_class->class)) {
|
||||
ret = IS_ERR(uio_class->class);
|
||||
printk(KERN_ERR "class_create failed for uio\n");
|
||||
goto err_class_create;
|
||||
}
|
||||
return 0;
|
||||
|
||||
err_class_create:
|
||||
kfree(uio_class);
|
||||
uio_class = NULL;
|
||||
err_kzalloc:
|
||||
uio_major_cleanup();
|
||||
exit:
|
||||
return ret;
|
||||
}
|
||||
|
||||
static void release_uio_class(struct kref *kref)
|
||||
{
|
||||
/* Ok, we cheat as we know we only have one uio_class */
|
||||
class_destroy(uio_class->class);
|
||||
kfree(uio_class);
|
||||
uio_major_cleanup();
|
||||
uio_class = NULL;
|
||||
}
|
||||
|
||||
static void uio_class_destroy(void)
|
||||
{
|
||||
if (uio_class)
|
||||
kref_put(&uio_class->kref, release_uio_class);
|
||||
}
|
||||
|
||||
/**
|
||||
* uio_register_device - register a new userspace IO device
|
||||
* @owner: module that creates the new device
|
||||
* @parent: parent device
|
||||
* @info: UIO device capabilities
|
||||
*
|
||||
* returns zero on success or a negative error code.
|
||||
*/
|
||||
int __uio_register_device(struct module *owner,
|
||||
struct device *parent,
|
||||
struct uio_info *info)
|
||||
{
|
||||
struct uio_device *idev;
|
||||
int ret = 0;
|
||||
|
||||
if (!parent || !info || !info->name || !info->version)
|
||||
return -EINVAL;
|
||||
|
||||
info->uio_dev = NULL;
|
||||
|
||||
ret = init_uio_class();
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
idev = kzalloc(sizeof(*idev), GFP_KERNEL);
|
||||
if (!idev) {
|
||||
ret = -ENOMEM;
|
||||
goto err_kzalloc;
|
||||
}
|
||||
|
||||
idev->owner = owner;
|
||||
idev->info = info;
|
||||
init_waitqueue_head(&idev->wait);
|
||||
atomic_set(&idev->event, 0);
|
||||
|
||||
ret = uio_get_minor(idev);
|
||||
if (ret)
|
||||
goto err_get_minor;
|
||||
|
||||
idev->dev = device_create(uio_class->class, parent,
|
||||
MKDEV(uio_major, idev->minor),
|
||||
"uio%d", idev->minor);
|
||||
if (IS_ERR(idev->dev)) {
|
||||
printk(KERN_ERR "UIO: device register failed\n");
|
||||
ret = PTR_ERR(idev->dev);
|
||||
goto err_device_create;
|
||||
}
|
||||
dev_set_drvdata(idev->dev, idev);
|
||||
|
||||
ret = uio_dev_add_attributes(idev);
|
||||
if (ret)
|
||||
goto err_uio_dev_add_attributes;
|
||||
|
||||
info->uio_dev = idev;
|
||||
|
||||
if (idev->info->irq >= 0) {
|
||||
ret = request_irq(idev->info->irq, uio_interrupt,
|
||||
idev->info->irq_flags, idev->info->name, idev);
|
||||
if (ret)
|
||||
goto err_request_irq;
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
||||
err_request_irq:
|
||||
uio_dev_del_attributes(idev);
|
||||
err_uio_dev_add_attributes:
|
||||
device_destroy(uio_class->class, MKDEV(uio_major, idev->minor));
|
||||
err_device_create:
|
||||
uio_free_minor(idev);
|
||||
err_get_minor:
|
||||
kfree(idev);
|
||||
err_kzalloc:
|
||||
uio_class_destroy();
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(__uio_register_device);
|
||||
|
||||
/**
|
||||
* uio_unregister_device - unregister a industrial IO device
|
||||
* @info: UIO device capabilities
|
||||
*
|
||||
*/
|
||||
void uio_unregister_device(struct uio_info *info)
|
||||
{
|
||||
struct uio_device *idev;
|
||||
|
||||
if (!info || !info->uio_dev)
|
||||
return;
|
||||
|
||||
idev = info->uio_dev;
|
||||
|
||||
uio_free_minor(idev);
|
||||
|
||||
if (info->irq >= 0)
|
||||
free_irq(info->irq, idev);
|
||||
|
||||
uio_dev_del_attributes(idev);
|
||||
|
||||
dev_set_drvdata(idev->dev, NULL);
|
||||
device_destroy(uio_class->class, MKDEV(uio_major, idev->minor));
|
||||
kfree(idev);
|
||||
uio_class_destroy();
|
||||
|
||||
return;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(uio_unregister_device);
|
||||
|
||||
static int __init uio_init(void)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void __exit uio_exit(void)
|
||||
{
|
||||
}
|
||||
|
||||
module_init(uio_init)
|
||||
module_exit(uio_exit)
|
||||
MODULE_LICENSE("GPL v2");
|
||||
|
|
@ -0,0 +1,91 @@
|
|||
/*
|
||||
* include/linux/uio_driver.h
|
||||
*
|
||||
* 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 driver.
|
||||
*
|
||||
* Licensed under the GPLv2 only.
|
||||
*/
|
||||
|
||||
#ifndef _UIO_DRIVER_H_
|
||||
#define _UIO_DRIVER_H_
|
||||
|
||||
#include <linux/module.h>
|
||||
#include <linux/fs.h>
|
||||
#include <linux/interrupt.h>
|
||||
|
||||
/**
|
||||
* struct uio_mem - description of a UIO memory region
|
||||
* @kobj: kobject for this mapping
|
||||
* @addr: address of the device's memory
|
||||
* @size: size of IO
|
||||
* @memtype: type of memory addr points to
|
||||
* @internal_addr: ioremap-ped version of addr, for driver internal use
|
||||
*/
|
||||
struct uio_mem {
|
||||
struct kobject kobj;
|
||||
unsigned long addr;
|
||||
unsigned long size;
|
||||
int memtype;
|
||||
void __iomem *internal_addr;
|
||||
};
|
||||
|
||||
#define MAX_UIO_MAPS 5
|
||||
|
||||
struct uio_device;
|
||||
|
||||
/**
|
||||
* struct uio_info - UIO device capabilities
|
||||
* @uio_dev: the UIO device this info belongs to
|
||||
* @name: device name
|
||||
* @version: device driver version
|
||||
* @mem: list of mappable memory regions, size==0 for end of list
|
||||
* @irq: interrupt number or UIO_IRQ_CUSTOM
|
||||
* @irq_flags: flags for request_irq()
|
||||
* @priv: optional private data
|
||||
* @handler: the device's irq handler
|
||||
* @mmap: mmap operation for this uio device
|
||||
* @open: open operation for this uio device
|
||||
* @release: release operation for this uio device
|
||||
*/
|
||||
struct uio_info {
|
||||
struct uio_device *uio_dev;
|
||||
char *name;
|
||||
char *version;
|
||||
struct uio_mem mem[MAX_UIO_MAPS];
|
||||
long irq;
|
||||
unsigned long irq_flags;
|
||||
void *priv;
|
||||
irqreturn_t (*handler)(int irq, struct uio_info *dev_info);
|
||||
int (*mmap)(struct uio_info *info, struct vm_area_struct *vma);
|
||||
int (*open)(struct uio_info *info, struct inode *inode);
|
||||
int (*release)(struct uio_info *info, struct inode *inode);
|
||||
};
|
||||
|
||||
extern int __must_check
|
||||
__uio_register_device(struct module *owner,
|
||||
struct device *parent,
|
||||
struct uio_info *info);
|
||||
static inline int __must_check
|
||||
uio_register_device(struct device *parent, struct uio_info *info)
|
||||
{
|
||||
return __uio_register_device(THIS_MODULE, parent, info);
|
||||
}
|
||||
extern void uio_unregister_device(struct uio_info *info);
|
||||
extern void uio_event_notify(struct uio_info *info);
|
||||
|
||||
/* defines for uio_device->irq */
|
||||
#define UIO_IRQ_CUSTOM -1
|
||||
#define UIO_IRQ_NONE -2
|
||||
|
||||
/* defines for uio_device->memtype */
|
||||
#define UIO_MEM_NONE 0
|
||||
#define UIO_MEM_PHYS 1
|
||||
#define UIO_MEM_LOGICAL 2
|
||||
#define UIO_MEM_VIRTUAL 3
|
||||
|
||||
#endif /* _LINUX_UIO_DRIVER_H_ */
|
||||
Loading…
Reference in New Issue