The following implementation of ppoll() and pselect() system calls
depends on the architecture providing a TIF_RESTORE_SIGMASK flag in the
thread_info.
These system calls have to change the signal mask during their
operation, and signal handlers must be invoked using the new, temporary
signal mask. The old signal mask must be restored either upon successful
exit from the system call, or upon returning from the invoked signal
handler if the system call is interrupted. We can't simply restore the
original signal mask and return to userspace, since the restored signal
mask may actually block the signal which interrupted the system call.
The TIF_RESTORE_SIGMASK flag deals with this by causing the syscall exit
path to trap into do_signal() just as TIF_SIGPENDING does, and by
causing do_signal() to use the saved signal mask instead of the current
signal mask when setting up the stack frame for the signal handler -- or
by causing do_signal() to simply restore the saved signal mask in the
case where there is no handler to be invoked.
The first patch implements the sys_pselect() and sys_ppoll() system
calls, which are present only if TIF_RESTORE_SIGMASK is defined. That
#ifdef should go away in time when all architectures have implemented
it. The second patch implements TIF_RESTORE_SIGMASK for the PowerPC
kernel (in the -mm tree), and the third patch then removes the
arch-specific implementations of sys_rt_sigsuspend() and replaces them
with generic versions using the same trick.
The fourth and fifth patches, provided by David Howells, implement
TIF_RESTORE_SIGMASK for FR-V and i386 respectively, and the sixth patch
adds the syscalls to the i386 syscall table.
This patch:
Add the pselect() and ppoll() system calls, providing core routines usable by
the original select() and poll() system calls and also the new calls (with
their semantics w.r.t timeouts).
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The TIF_RESTORE_SIGMASK flag allows us to have a generic implementation of
sys_rt_sigsuspend() instead of duplicating it for each architecture. This
provides such an implementation and makes arch/powerpc use it.
It also tidies up the ppc32 sys_sigsuspend() to use TIF_RESTORE_SIGMASK.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Here is a series of patches which introduce in total 13 new system calls
which take a file descriptor/filename pair instead of a single file
name. These functions, openat etc, have been discussed on numerous
occasions. They are needed to implement race-free filesystem traversal,
they are necessary to implement a virtual per-thread current working
directory (think multi-threaded backup software), etc.
We have in glibc today implementations of the interfaces which use the
/proc/self/fd magic. But this code is rather expensive. Here are some
results (similar to what Jim Meyering posted before).
The test creates a deep directory hierarchy on a tmpfs filesystem. Then
rm -fr is used to remove all directories. Without syscall support I get
this:
real 0m31.921s
user 0m0.688s
sys 0m31.234s
With syscall support the results are much better:
real 0m20.699s
user 0m0.536s
sys 0m20.149s
The interfaces are for obvious reasons currently not much used. But they'll
be used. coreutils (and Jeff's posixutils) are already using them.
Furthermore, code like ftw/fts in libc (maybe even glob) will also start using
them. I expect a patch to make follow soon. Every program which is walking
the filesystem tree will benefit.
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@ftp.linux.org.uk>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
One of the things that's confusing about nfsd4_lock is that the lk_stateowner
field could be set to either of two different lockowners: the open owner or
the lock owner. Rename to lk_replay_owner and add a comment to make it clear
that it's used for whichever stateowner has its sequence id bumped for replay
detection.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The server code currently keeps track of the destination address on every
request so that it can reply using the same address. However we forget to do
that in the case of a deferred request. Remedy this oversight. >From folks
at PolyServe.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change nfsd_sync_dir to return an error if ->sync fails, and pass that error
up through the stack. This involves a number of rearrangements of error
paths, and care to distinguish between Linux -errno numbers and NFSERR
numbers.
In the 'create' routines, we continue with the 'setattr' even if a previous
sync_dir failed.
This patch is quite different from Takashi's in a few ways, but there is still
a strong lineage.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
All standard system calls should be declared in include/linux/syscalls.h.
Add some of the new additions that were previously missed.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes a regression in 2.6.14 against 2.6.13 that causes an
imbalance in memory allocation during bootup.
The slab allocator in 2.6.13 is not numa aware and simply calls
alloc_pages(). This means that memory policies may control the behavior of
alloc_pages(). During bootup the memory policy is set to MPOL_INTERLEAVE
resulting in the spreading out of allocations during bootup over all
available nodes. The slab allocator in 2.6.13 has only a single list of
slab pages. As a result the per cpu slab cache and the spinlock controlled
page lists may contain slab entries from off node memory. The slab
allocator in 2.6.13 makes no effort to discern the locality of an entry on
its lists.
The NUMA aware slab allocator in 2.6.14 controls locality of the slab pages
explicitly by calling alloc_pages_node(). The NUMA slab allocator manages
slab entries by having lists of available slab pages for each node. The
per cpu slab cache can only contain slab entries associated with the node
local to the processor. This guarantees that the default allocation mode
of the slab allocator always assigns local memory if available.
Setting MPOL_INTERLEAVE as a default policy during bootup has no effect
anymore. In 2.6.14 all node unspecific slab allocations are performed on
the boot processor. This means that most of key data structures are
allocated on one node. Most processors will have to refer to these
structures making the boot node a potential bottleneck. This may reduce
performance and cause unnecessary memory pressure on the boot node.
This patch implements NUMA policies in the slab layer. There is the need
of explicit application of NUMA memory policies by the slab allcator itself
since the NUMA slab allocator does no longer let the page_allocator control
locality.
The check for policies is made directly at the beginning of __cache_alloc
using current->mempolicy. The memory policy is already frequently checked
by the page allocator (alloc_page_vma() and alloc_page_current()). So it
is highly likely that the cacheline is present. For MPOL_INTERLEAVE
kmalloc() will spread out each request to one node after another so that an
equal distribution of allocations can be obtained during bootup.
It is not possible to push the policy check to lower layers of the NUMA
slab allocator since the per cpu caches are now only containing slab
entries from the current node. If the policy says that the local node is
not to be preferred or forbidden then there is no point in checking the
slab cache or local list of slab pages. The allocation better be directed
immediately to the lists containing slab entries for the allowed set of
nodes.
This way of applying policy also fixes another strange behavior in 2.6.13.
alloc_pages() is controlled by the memory allocation policy of the current
process. It could therefore be that one process is running with
MPOL_INTERLEAVE and would f.e. obtain a new page following that policy
since no slab entries are in the lists anymore. A page can typically be
used for multiple slab entries but lets say that the current process is
only using one. The other entries are then added to the slab lists. These
are now non local entries in the slab lists despite of the possible
availability of local pages that would provide faster access and increase
the performance of the application.
Another process without MPOL_INTERLEAVE may now run and expect a local slab
entry from kmalloc(). However, there are still these free slab entries
from the off node page obtained from the other process via MPOL_INTERLEAVE
in the cache. The process will then get an off node slab entry although
other slab entries may be available that are local to that process. This
means that the policy if one process may contaminate the locality of the
slab caches for other processes.
This patch in effect insures that a per process policy is followed for the
allocation of slab entries and that there cannot be a memory policy
influence from one process to another. A process with default policy will
always get a local slab entry if one is available. And the process using
memory policies will get its memory arranged as requested. Off-node slab
allocation will require the use of spinlocks and will make the use of per
cpu caches not possible. A process using memory policies to redirect
allocations offnode will have to cope with additional lock overhead in
addition to the latency added by the need to access a remote slab entry.
Changes V1->V2
- Remove #ifdef CONFIG_NUMA by moving forward declaration into
prior #ifdef CONFIG_NUMA section.
- Give the function determining the node number to use a saner
name.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
proc support for zone reclaim
This patch creates a proc entry /proc/sys/vm/zone_reclaim_mode that may be
used to override the automatic determination of the zone reclaim made on
bootup.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some bits for zone reclaim exists in 2.6.15 but they are not usable. This
patch fixes them up, removes unused code and makes zone reclaim usable.
Zone reclaim allows the reclaiming of pages from a zone if the number of
free pages falls below the watermarks even if other zones still have enough
pages available. Zone reclaim is of particular importance for NUMA
machines. It can be more beneficial to reclaim a page than taking the
performance penalties that come with allocating a page on a remote zone.
Zone reclaim is enabled if the maximum distance to another node is higher
than RECLAIM_DISTANCE, which may be defined by an arch. By default
RECLAIM_DISTANCE is 20. 20 is the distance to another node in the same
component (enclosure or motherboard) on IA64. The meaning of the NUMA
distance information seems to vary by arch.
If zone reclaim is not successful then no further reclaim attempts will
occur for a certain time period (ZONE_RECLAIM_INTERVAL).
This patch was discussed before. See
http://marc.theaimsgroup.com/?l=linux-kernel&m=113519961504207&w=2http://marc.theaimsgroup.com/?l=linux-kernel&m=113408418232531&w=2http://marc.theaimsgroup.com/?l=linux-kernel&m=113389027420032&w=2http://marc.theaimsgroup.com/?l=linux-kernel&m=113380938612205&w=2
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Migration code currently does not take a reference to target page
properly, so between unlocking the pte and trying to take a new
reference to the page with isolate_lru_page, anything could happen to
it.
Fix this by holding the pte lock until we get a chance to elevate the
refcount.
Other small cleanups while we're here.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There is a new device which is look like:
Serial controller: Decision Computer International Co. PCCOM2 (rev 02) (prog-if 02 [16550])
0700: 6666:0004 (rev 02) (prog-if 02)
Flags: medium devsel, IRQ 177
Memory at fe000000 (32-bit, non-prefetchable) [size=128]
I/O ports at e880 [size=128]
I/O ports at e400 [size=256]
It has two 16550A, and is not listed in kernel, although the
manufacturer clams that it is supported...
I've created the following patch, it only add the new PCI id and the
card to the repository, it seems to work.
Signed-off-by: Alon Bar-Lev <alon.barlev@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Added macros for min/default/max link priority in tipc_config.h.
Also renamed TIPC_NUM_LINK_PRI to TIPC_MEDIA_LINK_PRI since that
is a more accurate description of what it is used for.
Signed-off-by: Per Liden <per.liden@ericsson.com>
Some subsystems, such as PPP, can send negative values
here. It just happened to work correctly on 32-bit with
an unsigned value, but on 64-bit this explodes.
Figured out by Paul Mackerras based upon several PPP crash
reports.
Signed-off-by: David S. Miller <davem@davemloft.net>
These definitions ware used for only internal use in kernel <= 2.6.13,
which had not introduced the unified parser of IPv6 extension header yet.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Procfs always output IPV6 addresses without the colon
characters, and we cannot change that.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add __meminit to the __init lineup to ensure functions default
to __init when memory hotplug is not enabled. Replace __devinit
with __meminit on functions that were changed when the memory
hotplug code was introduced.
Signed-off-by: Matt Tolentino <matthew.e.tolentino@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds kexec() support for SH.
Signed-off-by: kogiidena <kogiidena@eggplant.ddo.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cc: <fastboot@lists.osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If optimizing for size (CONFIG_CC_OPTIMIZE_FOR_SIZE), allow gcc4 compilers
to decide what to inline and what not - instead of the kernel forcing gcc
to inline all the time. This requires several places that require to be
inlined to be marked as such, previous patches in this series do that.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Arjan van de Ven <arjan@infradead.org>
Mark a number of functions as 'must inline'. The functions affected by this
patch need to be inlined because they use knowledge that their arguments are
constant so that most of the function optimizes away. At this point this
patch does not change behavior, it's for documentation only (and for future
patches in the inline series)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch is the first in a series that tries to optimize the kernel in terms
of size (and thus cache behavior, both cpu and pagecache).
This first patch changes __always_inline to be a forced inline instead of the
"regular" inline it was on everything except alpha. This forced inline
matches the intention of the define better as a matter of documentation.
There is no change in behavior by this patch, since "inline" currently is
mapped to a forced inline anyway.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
No need for a file argument. If we'd really need it it's in vma->vm_file
already. gbefb and sgivwfb used to set vma->vm_file to the file argument, but
the kernel alrady did that.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The ioctl and file arguments to ->fb_mmap are totally unused and there's not
reason a driver should need them.
Also update the ->fb_compat_ioctl prototype to be the same as ->fb_mmap.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove the remaining kmalloc() wrapper bits from fs/smbfs/.
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The problem, reported in:
http://bugzilla.kernel.org/show_bug.cgi?id=5859
and by various other email messages and lkml posts is that the cpuset hook
in the oom (out of memory) code can try to take a cpuset semaphore while
holding the tasklist_lock (a spinlock).
One must not sleep while holding a spinlock.
The fix seems easy enough - move the cpuset semaphore region outside the
tasklist_lock region.
This required a few lines of mechanism to implement. The oom code where
the locking needs to be changed does not have access to the cpuset locks,
which are internal to kernel/cpuset.c only. So I provided a couple more
cpuset interface routines, available to the rest of the kernel, which
simple take and drop the lock needed here (cpusets callback_sem).
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
finish_arch_switch needs to update the user cpu time as well, not just the
system cpu time. Otherwise the partial user cpu time of a process that is
stored in the lowcore will be (mis-)accounted to the next process.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Anything that writes into a tmpfs filesystem is liable to disproportionately
decrease the available memory on a particular node. Since there's no telling
what sort of application (e.g. dd/cp/cat) might be dropping large files
there, this lets the admin choose the appropriate default behavior for their
site's situation.
Introduce a tmpfs mount option which allows specifying a memory policy and
a second option to specify the nodelist for that policy. With the default
policy, tmpfs will behave as it does today. This patch adds support for
preferred, bind, and interleave policies.
The default policy will cause pages to be added to tmpfs files on the node
which is doing the writing. Some jobs expect a single process to create
and manage the tmpfs files. This results in a node which has a
significantly reduced number of free pages.
With this patch, the administrator can specify the policy and nodes for
that policy where they would prefer allocations.
This patch was originally written by Brent Casavant and Hugh Dickins. I
added support for the bind and preferred policies and the mpol_nodelist
mount option.
Signed-off-by: Brent Casavant <bcasavan@sgi.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some people apparently run CONFIG_NUMA without CONFIG_SWAP. The migration
code currently depends on swap. This patch provides a set of inline
fallback functions so that the kernel properly compiles. However, calls to
migration functions will fail.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a new SCHED_BATCH (3) scheduling policy: such tasks are presumed
CPU-intensive, and will acquire a constant +5 priority level penalty. Such
policy is nice for workloads that are non-interactive, but which do not
want to give up their nice levels. The policy is also useful for workloads
that want a deterministic scheduling policy without interactivity causing
extra preemptions (between that workload's tasks).
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add driver support for a 2 port PCI IOC3-based serial card on Altix boxes:
This is a re-submission. On the original submission I was asked to
organize the code so that the MIPS ioc3 ethernet and serial parts could be
used with this driver. Stanislaw Skowronek was kind enough to provide the
shim layer for this - thanks Stanislaw. This patch includes the shim layer
and the Altix PCI ioc3 serial driver. The MIPS merged ioc3 ethernet and
serial support is forthcoming.
Signed-off-by: Patrick Gefre <pfg@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
A Christoph suggested that the /proc/devices file be converted to use the
seq_file interface. This patch does that.
I've obxerved one or two installation that had sufficiently large sans that
they overran the 4k limit on /proc/devices.
Signed-off-by: Neil Horman <nhorman@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add software recognition for the new LSI Logic Fibre Channel controller.
Signed-off-by: Eric Moore <Eric.Moore@lsil.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
gcc4 generates warnings when a non-FASTCALL function pointer is assigned to a
FASTCALL one. Perhaps it has taste.
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This makes the SPI core and its users access transfers in the SPI message
structure as linked list not as an array, as discussed on LKML.
From: David Brownell <dbrownell@users.sourceforge.net>
Updates including doc, bugfixes to the list code, add
spi_message_add_tail(). Plus, initialize things _before_ grabbing the
locks in some cases (in case it grows more expensive). This also merges
some bitbang updates of mine that didn't yet make it into the mm tree.
Signed-off-by: Vitaly Wool <vwool@ru.mvista.com>
Signed-off-by: Dmitry Pervushin <dpervushin@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This was originally a driver for the ST M25P80 SPI flash. It's been
updated slightly to handle other M25P series chips.
For many of these chips, the specific type could be probed, but for now
this just requires static setup with flash_platform_data that lists the
chip type (size, format) and any default partitioning to use.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Mike Lavender <mike@steroidmicros.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds a bitbanging spi master, hooking up to board/adapter-specific glue
code which knows how to set and read the signals (gpios etc).
This code kicks in after the glue code creates a platform_device with the
right platform_data. That data includes I/O loops, which will usually
come from expanding an inline function (provided in the header). One goal
is that the I/O loops should be easily optimized down to a few GPIO register
accesses, in common cases, for speed and minimized overhead.
This understands all the currently defined protocol tweaking options in the
SPI framework, and might eventually serve as as reference implementation.
- different word sizes (1..32 bits)
- differing clock rates
- SPI modes differing by CPOL (affecting chip select and I/O loops)
- SPI modes differing by CPHA (affecting I/O loops)
- delays (usecs) after transfers
- temporarily deselecting chips in mid-transfer
A lot of hardware could work with this framework, though common types of
controller can't reach peak performance without switching to a driver
structure that supports pipelining of transfers (e.g. DMA queues) and maybe
controllers (e.g. IRQ driven).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This updates the ads7864 driver to use the new "spi_driver" struct, and
includes some minor unrelated cleanup.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This includes various updates to the SPI core:
- Fixes a driver model refcount bug in spi_unregister_master() paths.
- The spi_master structures now have wrappers which help keep drivers
from needing class-level get/put for device data or for refcounts.
- Check for a few setup errors that would cause oopsing later.
- Docs say more about memory management. Highlights the use of DMA-safe
i/o buffers, and zero-initializing spi_message and such metadata.
- Provide a simple alloc/free for spi_message and its spi_transfer;
this is only one of the possible memory management policies.
Nothing to break code that already works.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is a refresh of the "Simple SPI Framework" found in 2.6.15-rc3-mm1
which makes the following changes:
* There's now a "struct spi_driver". This increase the footprint
of the core a bit, since it now includes code to do what the driver
core was previously handling directly. Documentation and comments
were updated to match.
* spi_alloc_master() now does class_device_initialize(), so it can
at least be refcounted before spi_register_master(). To match,
spi_register_master() switched over to class_device_add().
* States explicitly that after transfer errors, spi_devices will be
deselected. We want fault recovery procedures to work the same
for all controller drivers.
* Minor tweaks: controller_data no longer points to readonly data;
prevent some potential cast-from-null bugs with container_of calls;
clarifies some existing kerneldoc,
And a few small cleanups.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is a conversion of the AT91rm9200 DataFlash MTD driver to use the
lightweight SPI framework, and no longer be AT91-specific. It compiles
down to less than 3KBytes on ARM.
The driver allows board-specific init code to provide platform_data with
the relevant MTD partitioning information, and hotplugs.
This version has been lightly tested. Its parent at91_dataflash driver has
been pretty well banged on, although kernel.org JFFS2 dataflash support was
acting broken the last time I tried it.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is a driver for the ADS7846 touchscreen sensor, derived from
the corgi_ts and omap_ts drivers. Key differences from those two:
- Uses the new SPI framework (minimalist version)
- <linux/spi/ads7846.h> abstracts board-specific touchscreen info
- Sysfs attributes for the temperature and voltage sensors
- Uses fewer ARM-specific IRQ primitives
The temperature and voltage sensors show up in sysfs like this:
$ pwd
/sys/devices/platform/omap-uwire/spi2.0
$ ls
bus@ input:event0@ power/ temp1 vbatt
driver@ modalias temp0 vaux
$ cat modalias
ads7846
$ cat temp0
991
$ cat temp1
1177
$
So far only basic testing has been done. There's a fair amount of hardware
that uses this sensor, and which also runs Linux, which should eventually
be able to use this driver.
One portability note may be of special interest. It turns out that not all
SPI controllers are happy issuing requests that do things like "write 8 bit
command, read 12 bit response". Most of them seem happy to handle various
word sizes, so the issue isn't "12 bit response" but rather "different rx
and tx write sizes", despite that being a common MicroWire convention. So
this version of the driver no longer reads 12 bit native-endian words; it
reads 16-bit big-endian responses, then byteswaps them and shifts the
results to discard the noise.
Signed-off-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is the core of a small SPI framework, implementing the model of a
queue of messages which complete asynchronously (with thin synchronous
wrappers on top).
- It's still less than 2KB of ".text" (ARM). If there's got to be a
mid-layer for something so simple, that's the right size budget. :)
- The guts use board-specific SPI device tables to build the driver
model tree. (Hardware probing is rarely an option.)
- This version of Kconfig includes no drivers. At this writing there
are two known master controller drivers (PXA/SSP, OMAP MicroWire)
and three protocol drivers (CS8415a, ADS7846, DataFlash) with LKML
mentions of other drivers in development.
- No userspace API. There are several implementations to compare.
Implement them like any other driver, and bind them with sysfs.
The changes from last version posted to LKML (on 11-Nov-2005) are minor,
and include:
- One bugfix (removes a FIXME), with the visible effect of making device
names be "spiB.C" where B is the bus number and C is the chipselect.
- The "caller provides DMA mappings" mechanism now has kerneldoc, for
DMA drivers that want to be fancy.
- Hey, the framework init can be subsys_init. Even though board init
logic fires earlier, at arch_init ... since the framework init is
for driver support, and the board init support uses static init.
- Various additional spec/doc clarifications based on discussions
with other folk. It adds a brief "thank you" at the end, for folk
who've helped nudge this framework into existence.
As I've said before, I think that "protocol tweaking" is the main support
that this driver framework will need to evolve.
From: Mark Underwood <basicmark@yahoo.com>
Update the SPI framework to remove a potential priority inversion case by
reverting to kmalloc if the pre-allocated DMA-safe buffer isn't available.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
David S. Miller