Commit Graph

143 Commits

Author SHA1 Message Date
Michael S. Tsirkin ccb86a6907 uio: add generic driver for PCI 2.3 devices
This adds a generic uio driver that can bind to any PCI device.  First
user will be virtualization where a qemu userspace process needs to give
guest OS access to the device.

Interrupts are handled using the Interrupt Disable bit in the PCI
command register and Interrupt Status bit in the PCI status register.
All devices compliant to PCI 2.3 (circa 2002) and all compliant PCI
Express devices should support these bits.  Driver detects this support,
and won't bind to devices which do not support the Interrupt Disable Bit
in the command register.

It's expected that more features of interest to virtualization will be
added to this driver in the future. Possibilities are: mmap for device
resources, MSI/MSI-X, eventfd (to interface with kvm), iommu.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Chris Wright <chrisw@redhat.com>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 09:50:48 -07:00
Daniel Mack 5b2ea2f10d UIO: remove 'default n' from Kconfig
'default n' is the default, there is no need for these lines.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 09:50:47 -07:00
Magnus Damm af76756e6e uio: Runtime PM for UIO devices
This patch modifies the uio_pdrv_genirq driver to support
Runtime PM. The power management implementation simply
runtime resumes the device at open() time and runtime
suspends it at release() time. The user space driver is
responsible for re-initializing the hardware after open().

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-23 18:03:19 +09:00
Hans J. Koch 912335c43b UIO: fix specific device driver missing statement for depmod
On Fri, Apr 10, 2009 at 01:50:50PM -0700, Andrew Morton wrote:
> On Fri, 10 Apr 2009 13:32:01 GMT
> bugzilla-daemon@bugzilla.kernel.org wrote:
> 
> > http://bugzilla.kernel.org/show_bug.cgi?id=13059

drivers/uio/uio_cif.c misses a MODULE_DEVICE_TABLE, this fixes it.

Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-16 16:17:11 -07:00
Ian Abbott 6da2d377bb UIO: Take offset into account when determining number of pages that can be mapped
If a UIO memory region does not start on a page boundary but straddles one,
the number of actual pages that overlap the memory region may be calculated
incorrectly because the offset isn't taken into account.  If userspace sets
the mmap length to offset+size, it may fail with -EINVAL if UIO thinks it's
trying to allocate too many pages.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Cc: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24 16:38:25 -07:00
Brandon Philips 1bafeb378e uio: add the uio_aec driver
UIO driver for the Adrienne Electronics Corporation PCI time code
device.

This device differs from other UIO devices since it uses I/O ports instead of
memory mapped I/O. In order to make it possible for UIO to work with this
device a utility, uioport, can be used to read and write the ports.

uioport is designed to be a setuid program and checks the permissions of
the /dev/uio* node and if the user has write permissions it will use
iopl and out*/in* to access the device.

[1] git clone git://ifup.org/philips/uioport.git

Signed-off-by: Brandon Philips <brandon@ifup.org>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24 16:38:24 -07:00
Hans J. Koch 8205779114 UIO: Add name attributes for mappings and port regions
If a UIO device has several memory mappings, it can be difficult for userspace
to find the right one. The situation becomes even worse if the UIO driver can
handle different versions of a card that have different numbers of mappings.
Benedikt Spranger has such cards and pointed this out to me. Thanks, Bene!

To address this problem, this patch adds "name" sysfs attributes for each
mapping. Userspace can use these to clearly identify each mapping. The name
string is optional. If a driver doesn't set it, an empty string will be
returned, so this patch won't break existing drivers.

The same problem exists for port region information, so a "name" attribute is
added there, too.

Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24 16:38:24 -07:00
Hans J. Koch e70c412ee4 UIO: Pass information about ioports to userspace (V2)
Devices sometimes have memory where all or parts of it can not be mapped to
userspace. But it might still be possible to access this memory from
userspace by other means. An example are PCI cards that advertise not only
mappable memory but also ioport ranges. On x86 architectures, these can be
accessed with ioperm, iopl, inb, outb, and friends. Mike Frysinger (CCed)
reported a similar problem on Blackfin arch where it doesn't seem to be easy
to mmap non-cached memory but it can still be accessed from userspace.

This patch allows kernel drivers to pass information about such ports to
userspace. Similar to the existing mem[] array, it adds a port[] array to
struct uio_info. Each port range is described by start, size, and porttype.

If a driver fills in at least one such port range, the UIO core will simply
pass this information to userspace by creating a new directory "portio"
underneath /sys/class/uio/uioN/. Similar to the "mem" directory, it will
contain a subdirectory (portX) for each port range given.

Note that UIO simply passes this information to userspace, it performs no
action whatsoever with this data. It's userspace's responsibility to obtain
access to these ports and to solve arch dependent issues. The "porttype"
attribute tells userspace what kind of port it is dealing with.

This mechanism could also be used to give userspace information about GPIOs
related to a device. You frequently find such hardware in embedded devices,
so I added a UIO_PORT_GPIO definition. I'm not really sure if this is a good
idea since there are other solutions to this problem, but it won't hurt much
anyway.

Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-06 10:44:44 -08:00
Mike Frysinger e543ae8966 UIO: uio_pdrv_genirq: allow custom irq_flags
I can't think of a reason why the driver prevents people from setting any
custom bits in their platform device, but I can think of some reasons for
allowing custom flags.  Like setting the IRQF_TRIGGER_... bits.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-06 10:44:43 -08:00
Arjan van de Ven 7898aa5c39 UIO: use pci_ioremap_bar() in drivers/uio
Use the newly introduced pci_ioremap_bar() function in drivers/uio.
pci_ioremap_bar() just takes a pci device and a bar number, with the goal
of making it really hard to get wrong, while also having a central place
to stick sanity checks.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-06 10:44:43 -08:00
Al Viro 233e70f422 saner FASYNC handling on file close
As it is, all instances of ->release() for files that have ->fasync()
need to remember to evict file from fasync lists; forgetting that
creates a hole and we actually have a bunch that *does* forget.

So let's keep our lives simple - let __fput() check FASYNC in
file->f_flags and call ->fasync() there if it's been set.  And lose that
crap in ->release() instances - leaving it there is still valid, but we
don't have to bother anymore.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-01 09:49:46 -07:00
Linus Torvalds 2bea2e4abf Merge branch 'bkl-removal' of git://git.lwn.net/linux-2.6
* 'bkl-removal' of git://git.lwn.net/linux-2.6:
  UIO: BKL removal
2008-10-20 13:42:14 -07:00
Jonathan Corbet 0d4a7bc12f UIO: BKL removal
Fill in needed locking around idr accesses, then remove the big kernel lock
from the UIO driver.  Since there are no in-tree UIO drivers with open()
methods, no further BKL pushdown is required.

Acked-by: Hans J. Koch <hjk@linutronix.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-10-16 12:32:26 -06:00
Andrew G. Harvey 02683ffdf6 UIO: Fix mapping of logical and virtual memory
mmap() doesn't work as expected for UIO_MEM_LOGICAL or UIO_MEM_VIRTUAL
mappings. The offset into the memory needs to be added, otherwise
uio_vma_fault always returns the first page only. Note that for UIO
userspace calls mmap() with offset = N * getpagesize() to access
mapping N. This must be compensated when calculating the offset. A
comment was added to explain this since it is not obvious.

Signed-off-by: Andrew G. Harvey <agh@cisco.com>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16 09:24:54 -07:00
John Ogness a6030fcc60 UIO: add automata sercos3 pci card support
Here is a new version of the patch to support the Automata Sercos III
PCI card driver. I now check that the IRQ is enabled before accepting
the interrupt.

I still use a logical OR to store the enabled interrupts and I've
added a second use of a logical OR when restoring the enabled
interrupts. I added an explanation of why I do this in comments at the
top of the source file.

Since I use a logical OR, I also removed the extra checks if the
Interrupt Enable Register and ier0_cache are 0.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16 09:24:53 -07:00
Hans J. Koch a6fcc3a196 UIO: Change driver name of uio_pdrv
The generic UIO platform device driver should be given a unique driver ID and
not just "uio". This is especially important since we now have a similar driver
named uio_pdrv_genirq. Currently, there's no user of this driver in the
mainline kernel.

Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16 09:24:53 -07:00
Hans J. Koch e2b39df119 UIO: Add alignment warnings for uio-mem
This patch adds an "offset" attribute for UIO mappings. It shows the
difference between the actual start address of the memory and the start
address of the page.

Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16 09:24:53 -07:00
Greg Kroah-Hartman a9b12619f7 device create: misc: convert device_create_drvdata to device_create
Now that device_create() has been audited, rename things back to the
original call to be sane.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16 09:24:43 -07:00
Magnus Damm c767db0ab4 UIO: generic irq handling for some uio platform devices
This is V3 of uio_pdrv_genirq.c, a platform driver for UIO with
generic IRQ handling code. This driver is very similar to the regular
UIO platform driver, but is only suitable for devices that are
connected to the interrupt controller using unique interrupt lines.

The uio_pdrv_genirq driver includes generic interrupt handling code
which disables the serviced interrupt in the interrupt controller
and makes the user space driver responsible for acknowledging the
interrupt in the device and reenabling the interrupt in the interrupt
controller.

Shared interrupts are not supported since the in-kernel interrupt
handler will disable the interrupt line in the interrupt controller,
and in a shared interrupt configuration this will stop other devices
from delivering interrupts.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-21 10:15:39 -07:00
Uwe Kleine-König 0f90927da1 UIO: uio_pdrv: fix license specification
Thanks to Magnus Damm for pointing that out.

Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Acked-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-21 10:15:39 -07:00
Uwe Kleine-König 331995e783 UIO: uio_pdrv: fix memory leak
Thanks to Magnus Damm for pointing that out.

Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Acked-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-21 10:15:38 -07:00
Uwe Kleine-König 4d80d59437 UIO: add generic UIO platform driver
This patch adds a generic UIO platform driver. It eliminates the need for a
dedicated kernel module for simple platform devices. Users only need to
implement their irq handler in platform code and fill a struct uio_info
there. This helps avoiding code duplication as UIO platform drivers often
share a lot of common code.

Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:55 -07:00
Hans J. Koch 328a14e70e UIO: Add write function to allow irq masking
Sometimes it is necessary to enable/disable the interrupt of a UIO device
from the userspace part of the driver. With this patch, the UIO kernel driver
can implement an "irqcontrol()" function that does this. Userspace can write
an s32 value to /dev/uioX (usually 0 or 1 to turn the irq off or on). The
UIO core will then call the driver's irqcontrol function.

Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Acked-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Acked-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:55 -07:00
Uwe Kleine-König 934da4766e UIO: fix UIO Kconfig dependencies
ae210f1886 introduced a big "if UIO"/"endif"
where all uio drivers are defined.  So know there is no need for them to
depend explicitly on UIO.

Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:53 -07:00
Jonathan Corbet 2fceef397f Merge commit 'v2.6.26' into bkl-removal 2008-07-14 15:29:34 -06:00
Jonathan Corbet fbc8a81d66 UIO: cdev lock_kernel() pushdown
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-06-20 14:05:47 -06:00
Greg Kroah-Hartman 43691da4ce UIO: fix race in device_create
There is a race from when a device is created with device_create() and
then the drvdata is set with a call to dev_set_drvdata() in which a
sysfs file could be open, yet the drvdata will be NULL, causing all
sorts of bad things to happen.

This patch fixes the problem by using the new function,
device_create_drvdata().

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-05-20 13:31:55 -07:00
Uwe Kleine-König 610ad5064c UIO: hold a reference to the device's owner while the device is open
Otherwise the device might just disappear while /dev/uioX is being used
which results in an Oops.

Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Signed-off-by: Hans J Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-19 19:10:18 -07:00
Ben Nizette b54f2863a2 UIO: Implement a UIO interface for the SMX Cryptengine
This patch implements a UIO interface for the SMX Cryptengine.

The Cryptengine found on the Nias Digital SMX board is best suited
for a UIO interface.  It is not wired in to the cryptographic API
as the engine handles it's own keys, algorithms, everything.  All
that we know about is that if there's room in the buffer, you can
write data to it and when there's data ready, you read it out again.

There isn't necessarily even any direct correlation between data
going in and data coming out again, the engine may consume or
generate data all on its own.

This driver is for proprietary hardware but we're always told to
submit the drivers anyway; here you are.  :-)

This is version 4 of this patch and addresses all issues raised by
Hans-Jürgen Koch and Paul Mundt in their reviews.  Slightly altered
is Paul's suggestion to use DRV_NAME and DRV_VERSION as the UIO
version and name.  While at the moment they are the same, there
is no reason for them to stay that way.  Nevertheless we now at
least provide a MODULE_VERSION macro to keep modinfo happy.

Signed-off-by: Ben Nizette <bn@niasdigital.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Hans J Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-19 19:10:18 -07:00
Hans-Jürgen Koch a2a6024692 UIO: Remove needless PCI_DEVICE_ID definition from uio_cif.c
Meanwhile, PCI_DEVICE_ID_PLX_9030 is defined in pci_ids.h, no need to
define it again in the driver.

Signed-off-by: Hans J. Koch <hjk@linutronix.de>
CC: Benedikt Spranger <b.spranger@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-19 19:10:18 -07:00
Denis Cheng 0732460b3a uio: mark pci_device_id hilscher_pci_ids[] __devinitdata
Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-19 19:10:17 -07:00
Denis Cheng ae210f1886 uio: Kconfig improvements
Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-19 19:10:17 -07:00
Jean-Samuel Chenard c9698d6b1a UIO: add pgprot_noncached() to UIO mmap code
Mapping of physical memory in UIO needs pgprot_noncached() to ensure
that IO memory is not cached. Without pgprot_noncached(), it (accidentally)
works on x86 and arm, but fails on PPC.

Signed-off-by: Jean-Samuel Chenard <jsamch@gmail.com>
Signed-off-by: Hans J Koch <hjk@linutronix.de>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-03-24 22:33:49 -07:00
Brandon Philips 4f808bcdf8 UIO: fix Greg's stupid changes
This fixes two bugs with UIO that cropped up recently in -rc1

1) WARNING: at fs/sysfs/file.c:334 sysfs_open_file when trying to open
   a map addr/size file - complaining about missing sysfs_ops for ktype

2) Permission denied when reading uio/uio0/maps/map0/{addr,size} when
   files are mode S_IRUGO

Also fix a typo: attr_attribute -> addr_attribute

Signed-off-by: Brandon Philips <bphilips@suse.de>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-21 15:27:07 -08:00
Nick Piggin a18b630d1b uio: nopage
Convert uio from nopage to fault.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Hans J Koch <hjk@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 10:41:07 -08:00
Jan Engelhardt 4f0146919b UIO: constify function pointer tables
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:43 -08:00
Greg Kroah-Hartman c10997f657 Kobject: convert drivers/* from kobject_unregister() to kobject_put()
There is no need for kobject_unregister() anymore, thanks to Kay's
kobject cleanup changes, so replace all instances of it with
kobject_put().


Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:40 -08:00
Greg Kroah-Hartman f9cb074bff Kobject: rename kobject_init_ng() to kobject_init()
Now that the old kobject_init() function is gone, rename
kobject_init_ng() to kobject_init() to clean up the namespace.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:38 -08:00
Greg Kroah-Hartman b2d6db5878 Kobject: rename kobject_add_ng() to kobject_add()
Now that the old kobject_add() function is gone, rename kobject_add_ng()
to kobject_add() to clean up the namespace.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:38 -08:00
Greg Kroah-Hartman 81e7c6a636 UIO: fix kobject usage
The uio kobject code is "wierd".  This patch should hopefully fix it up
to be sane and not leak memory anymore.


Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benedikt Spranger <b.spranger@linutronix.de>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:26 -08:00
Greg Kroah-Hartman 3514faca19 kobject: remove struct kobj_type from struct kset
We don't need a "default" ktype for a kset.  We should set this
explicitly every time for each kset.  This change is needed so that we
can make ksets dynamic, and cleans up one of the odd, undocumented
assumption that the kset/kobject/ktype model has.

This patch is based on a lot of help from Kay Sievers.

Nasty bug in the block code was found by Dave Young
<hidave.darkstar@gmail.com>

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:10 -08:00
Hans-Jürgen Koch bc4c4f45ac UIO: Hilscher CIF card driver
this is a patch that adds support for Hilscher CIF DeviceNet and
Profibus cards. I tested it on a Kontron CPX board, and Thomas reviewed
it.

You can find the user space part here:

http://www.osadl.org/projects/downloads/UIO/user/cif-0.1.0.tar.gz

Notes: cif_api.c is the main file you want to look at. It contains the
functions to open, close, mmap and so on. cif_dps.c adds functions
specific to Profibus cards, and cif_dn.c contains functions for
DeviceNet cards.  cif.c is a universal playground, it's just a small
test program.  The user space part of this UIO driver is still work in
progress, and not everything is tested yet. At the moment, the thread in
cif_api.c contains some code that artificially makes the card generate
interrupts, this was added for testing and will be removed later. But
the driver already contains all the functions needed for useful
operation, so it gives a good idea of how such a thing looks like.

For comparison, here's what you get from the manufacturer
(www.hilscher.com) when you ask for a Linux 2.6 driver:

http://www.tglx.de/private/hjk/cif-orig-2.6.tar.bz2

WARNING: Don't look at the code for too long, you might become sick :-)


Signed-off-by: Hans-Jürgen Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-18 15:57:16 -07:00
Hans J. Koch beafc54c4e 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>
2007-07-18 15:57:15 -07:00