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Patch from Tony Lindgren
Update OMAP timers from linux-omap tree. The highlights of the
patch are:
- Move timer32k code from mach-omap1 to plat-omap and make it
work also on omap24xx by Tony Lindgren
- Add support for dmtimer idle check for PM by Tuukka Tikkanen
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Tony Lindgren
Update OMAP clock framework from linux-omap tree.
The highlights of the patch are:
- Add support for omap730 clocks by Andrzej Zaborowski
- Fix compile warnings by Dirk Behme
- Add support for using dev id by Tony Lindgren and Komal Shah
- Move memory timings and PRCM into separate files by Tony Lindgren
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Andrew Victor
This patch updates the platform device resources for the Ethernet and
MMC peripherals. It also adds platform device information for the NAND
(SmartMedia), I2C and the RTC.
(This version of the patch can be applied before Patch 3392/1)
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Andrew Victor
On the Atmel AT91RM9200-DK and -EK boards, a pin is used to control
whether the card socket is used for a DataFlash Card or an MMC/SD card.
We now default to MMC/SD in the configuration files.
(This version of the patch can be applied before Patch 3392/1)
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Andrew Victor
This patch adds support for the LED(s) on the AT91RM9200-based boards.
(This version of the patch can be applied before Patch 3392/1)
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Richard Purdie
Force the Sharp Zaurus Poodle memory size to 32MB.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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board
Patch from Pavel Pisa
From: Stefano Fedrigo <aleph@develer.com>
This adds to the MX1ADS platform the needed code to detect
insertion/removal of an MMC/SD card. Tested on a v1.1 board.
Signed-off-by: Stefano Fedrigo <aleph@develer.com>
Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Pavel Pisa
This patch contains simplified set of changes to add scatter-gather
emulation capability into MX1 DMA support. The result should
be still usable for next combination of DMA transfers
Statter-Gather/linear/2D/FIFO to linear/2D/FIFO and
linear/2D/FIFO to Statter-Gather/2D/FIFO
The patch corrects channel priority allocation to be compatible
with MX1 hardware implementation.
Previous code has not been adapted from its PXA original.
Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Lennert Buytenhek
Instantiate the recently merged m48t86 rtc driver in the ts72xx code.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Lennert Buytenhek
Instantiate the recently merged ep93xx rtc driver in the ep93xx code.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Ben Dooks
NAND definitions for the HP iPAQ RX3715's
internal NAND flash
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Ben Dooks
The NAND timings on the Anubis are too large
to be selected when running at 133MHz memory
clock.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Ben Dooks
Fix the bug in the UPLL enable code which should
have put a 200uS delay in if enabling the USB PLL
from the state where it is off.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Ben Dooks
Add SMDK2410/SMDK2440 NAND device information
and default partition table.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Ben Dooks
Set default state of LEDs to off
Fixes context of Patch #3442/1
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Ben Dooks
Remove the old debug from the IRQ entry code,
update the comments on the handling of the
IRQ registers.
The message "bad interrupt offset" is removed
as it is only helpful for debugging, and can
cause printk() flooding when under load.
Make the code to deal with GPIO interrupts
faster, and use the same path to deal with
unexplained results from the IRQ registers.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Lennert Buytenhek
This patch adds support for the I/O coherent cache available on the
xsc3. The approach is to provide a simple API to determine whether the
chipset supports coherency by calling arch_is_coherent() and then
setting the appropriate system memory PTE and PMD bits. In addition,
we call this API on dma_alloc_coherent() and dma_map_single() calls.
A generic version exists that will compile out all the coherency-related
code that is not needed on the majority of ARM systems.
Note that we do not check for coherency in the dma_alloc_writecombine()
function as that still requires a special PTE setting. We also don't
touch dma_mmap_coherent() as that is a special ARM-only API that is by
definition only used on non-coherent system.
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Ben Dooks
The SMDK2410 and SMDK2440 boards have a number of items
in common, including the LEDs, Ethernet, PCMCIA. Make
a common SMDK support file.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Lennert Buytenhek
On the Double Espresso board, the IXP2350s are PCI slave devices and
we skip calling pci_common_init() as that enumerates the bus. But even
though we are a PCI slave device, there is still some PCI-related setup
that has to be done.
Create ixp23xx_pci_common_init(), move the common initialisation bits
there, and have this function called from both the PCI master and the
PCI slave init path.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Pavel Machek
> The kautobuild found the following error while trying to build 2.6.16-git18
> using collie_defconfig:
>
> arch/arm/mach-sa1100/collie.c:92: error: 'collie_uart_set_mctrl' undeclared here (not in a function)
> arch/arm/mach-sa1100/collie.c:93: error: 'collie_uart_get_mctrl' undeclared here (not in a function)
> make[1]: *** [arch/arm/mach-sa1100/collie.o] Error 1
> make: *** [arch/arm/mach-sa1100] Error 2
> make: Leaving directory `/var/tmp/kernel-orig'
This fixes above compile error by adding missing pieces of uart
support, and fixes compilation.
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Patch from Komal Shah
This patch fixes the duplicate exports of string library functions.
Signed-off-by: Komal Shah <komal_shah802003@yahoo.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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* master.kernel.org:/home/rmk/linux-2.6-serial:
[SERIAL] Allow 8250 PCI, PNP, GSC and HP300 support to be disabled
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* master.kernel.org:/home/rmk/linux-2.6-mmc:
[MMC] Pass -DDEBUG on compiler command line if MMC_DEBUG selected
[MMC] Add OMAP MMC host driver
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* master.kernel.org:/home/rmk/linux-2.6-arm:
[ARM] 3424/2: ixp23xx: fix uncompress.h for recent CRLF decompressor change
[ARM] 3434/1: pxa i2s amsl define
[ARM] 3425/1: xsc3: need to include pgtable-hwdef.h
[ARM] Allow un-muxed syscalls to be available for everyone
[ARM] 3420/1: Missing clobber in example code
[ARM] nommu: fixups for the exception vectors
[ARM] nommu: add nommu specific Kconfig and MMUEXT variable in Makefile
[ARM] nommu: start-up code
[ARM] nommu: MPU support in boot/compressed/head.S
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git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
[IA64] Avoid "u64 foo : 32;" for gcc3 vs. gcc4 compatibility
[IA64] Export cpu cache info by sysfs
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* master.kernel.org:/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
[CIFS] Fix typo in earlier cifs_unlink change and protect one
[CIFS] Incorrect signature sent on SMB Read
[CIFS] Fix unlink oops when indirectly called in rename error path
[CIFS] Fix two remaining coverity scan tool warnings.
[CIFS] Set correct lock type on new posix unlock call
[CIFS] Upate cifs change log
[CIFS] Fix slow oplock break response when mounts to different
[CIFS] Workaround various server bugs found in testing at connectathon
[CIFS] Allow fallback for setting file size to Procom SMB server when
[CIFS] Make POSIX CIFS Extensions SetFSInfo match exactly what we want
[CIFS] Move noisy debug message (triggerred by some older servers) from
[CIFS] Use correct pid on new cifs posix byte range lock call
[CIFS] Add posix (advisory) byte range locking support to cifs client
[CIFS] CIFS readdir perf optimizations part 1
[CIFS] Free small buffers earlier so we exceed the cifs
[CIFS] Fix large (ie over 64K for MaxCIFSBufSize) buffer case for wrapping
[CIFS] Convert remaining places in fs/cifs from
[CIFS] SessionSetup cleanup part 2
[CIFS] fix compile error (typo) and warning in cifssmb.c
[CIFS] Cleanup NTLMSSP session setup handling
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extra path.
Since cifs_unlink can also be called from rename path and there
was one report of oops am making the extra check for null inode.
Signed-off-by: Steve French <sfrench@us.ibm.com>
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Fixes Samba bug 3621 and kernel.org bug 6147
For servers which require SMB/CIFS packet signing, we were sending the
wrong signature (all zeros) on SMB Read request. The new cifs routine
to do signatures across an iovec was not complete - and SMB Read, unlike
the new SMBWrite2, did not fall back to the older routine (ie use
SendReceive vs. the more efficient SendReceive2 ie used the older
cifs_sign_smb vs. the disabled cifs_sign_smb2) for calculating signatures.
This finishes up cifs_sign_smb2/cifs_calc_signature2 so that the callers
of SendReceive2 can get SMB/CIFS packet signatures.
Now that cifs_sign_smb2 is supported, we could start using it in
the write path but this smaller fix does not include the change
to use SMBWrite2 when signatures are required (which when enabled
will make more Writes more efficient and alloc less memory).
Currently Write2 is only used when signatures are not
required at the moment but after more testing we will enable
that as well).
Thanks to James Slepicka and Sam Flory for initial investigation.
Signed-off-by: Steve French <sfrench@us.ibm.com>
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* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
[NET]: Allow skb headroom to be overridden
[TCP]: Kill unused extern decl for tcp_v4_hash_connecting()
[NET]: add SO_RCVBUF comment
[NET]: Deinline some larger functions from netdevice.h
[DCCP]: Use NULL for pointers, comfort sparse.
[DECNET]: Fix refcount
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Commit 70674f95c0a2ea694d5c39f4e514f538a09be36f:
[PATCH] Optimize select/poll by putting small data sets on the stack
resulted in the poll stack being 4-byte aligned on 64-bit architectures,
causing misaligned accesses to elements in the array.
This patch fixes it by declaring the stack in terms of 'long' instead
of 'char'.
Force alignment of poll and select stacks to long to avoid unaligned
access on 64 bit architectures.
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev:
[PATCH] libata: fix ata_xfer_tbl termination
[PATCH] libata: make ata_qc_issue complete failed qcs
[PATCH] libata: fix ata_qc_issue failure path
[PATCH] ata_piix: fix ich6/m_map_db
[libata] ahci: add ATI SB600 PCI IDs
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The attached patch documents the Linux kernel's memory barriers.
I've updated it from the comments I've been given.
The per-arch notes sections are gone because it's clear that there are so many
exceptions, that it's not worth having them.
I've added a list of references to other documents.
I've tried to get rid of the concept of memory accesses appearing on the bus;
what matters is apparent behaviour with respect to other observers in the
system.
Interrupts barrier effects are now considered to be non-existent. They may be
there, but you may not rely on them.
I've added a couple of definition sections at the top of the document: one to
specify the minimum execution model that may be assumed, the other to specify
what this document refers to by the term "memory".
I've made greater mention of the use of mmiowb().
I've adjusted the way in which caches are described, and described the fun
that can be had with cache coherence maintenance being unordered and data
dependency not being necessarily implicit.
I've described (smp_)read_barrier_depends().
I've rearranged the order of the sections, so that memory barriers are
discussed in abstract first, and then described the memory barrier facilities
available on Linux, before going on to more real-world discussions and examples.
I've added information about the lack of memory barriering effects with atomic
ops and bitops.
I've added information about control dependencies.
I've added more diagrams to illustrate caching interactions between CPUs.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Wrong error path in dup_fd() - it should return NULL on error,
not an address of already freed memory :/
Triggered by OpenVZ stress test suite.
What is interesting is that it was causing different oopses in RCU like
below:
Call Trace:
[<c013492c>] rcu_do_batch+0x2c/0x80
[<c0134bdd>] rcu_process_callbacks+0x3d/0x70
[<c0126cf3>] tasklet_action+0x73/0xe0
[<c01269aa>] __do_softirq+0x10a/0x130
[<c01058ff>] do_softirq+0x4f/0x60
=======================
[<c0113817>] smp_apic_timer_interrupt+0x77/0x110
[<c0103b54>] apic_timer_interrupt+0x1c/0x24
Code: Bad EIP value.
<0>Kernel panic - not syncing: Fatal exception in interrupt
Signed-Off-By: Pavel Emelianov <xemul@sw.ru>
Signed-Off-By: Dmitry Mishin <dim@openvz.org>
Signed-Off-By: Kirill Korotaev <dev@openvz.org>
Signed-Off-By: Linus Torvalds <torvalds@osdl.org>
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Turn some macros into inline functions and add proper type checking as
well as being more readable. Also a minor comment adjustment.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Decrease the number of pointer derefs in drivers/serial/jsm/jsm_tty.c
Benefits of the patch:
- Fewer pointer dereferences should make the code slightly faster.
- Size of generated code is smaller
- Improved readability
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: "V. ANANDA KRISHNAN" <mansarov@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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As announced, lookup_hash() can now become static.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The only user of get_wchan is the proc fs - and proc can't be built modular.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Signed-off-by: Brad Campbell <brad@wasp.net.au>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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And remove the comments that were put in inplace of a fix too....
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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during recovery
Currently a device failure during recovery leaves bits set in the bitmap.
This normally isn't a problem as the offending device will be rejected because
of errors. However if device re-adding is being used with non-persistent
bitmaps, this can be a problem.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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This patch removes the old radeon driver which has been replaced by a
newer one.
Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The monochrome->color expansion routine that handles bitmaps which have
(widths % 8) != 0 (slow_imageblit) produces corrupt characters in big-endian.
This is caused by a bogus bit test in slow_imageblit().
Fix.
This patch may deserve to go to the stable tree. The code has already been
well tested in little-endian machines. It's only in big-endian where there is
uncertainty and Herbert confirmed that this is the correct way to go.
It should not introduce regressions.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Acked-by: Herbert Poetzl <herbert@13thfloor.at>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Fixes for the pxafb driver:
* Return -EINVAL for resolutions that are too large as per framebuffer
driver policy.
* Increase the error timeout for disabling the LCD controller. The current
timeout is sometimes too short on the Sharp Zaurus Cxx00 hardware and an
extra delay in an error path shouldn't pose any problems.
* Fix a dev reference which causes a compile error when DEBUG is defined.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Generalise the Corgi backlight driver by moving the default intensity and
limit mask settings into the platform specific data structure. This enables
the driver to support other Zaurus hardware, specifically the SL-6000x (Tosa)
model.
Also change the spinlock to a mutex (the spinlock is overkill).
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Updates to the HP Jornada 680 Backlight driver:
- Correct the suspend/resume functions so the driver compiles
(SUSPEND_POWER_DOWN/RESUME_POWER_ON no longer exist).
- Convert the driver to match the recent platform device changes.
- Replace the unsafe static struct platform_device with dynamic allocation.
- Convert the driver to the new backlight code.
This has not been tested on a device due to lack of hardware but wouldn't
compile beforehand.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Backlight class attributes are currently easy to implement incorrectly.
Moving certain handling into the backlight core prevents this whilst at the
same time makes the drivers simpler and consistent. The following changes are
included:
The brightness attribute only sets and reads the brightness variable in the
backlight_properties structure.
The power attribute only sets and reads the power variable in the
backlight_properties structure.
Any framebuffer blanking events change a variable fb_blank in the
backlight_properties structure.
The backlight driver has only two functions to implement. One function is
called when any of the above properties change (to update the backlight
brightness), the second is called to return the current backlight brightness
value. A new attribute "actual_brightness" is added to return this brightness
as determined by the driver having combined all the above factors (and any
driver/device specific factors).
Additionally, the backlight core takes care of checking the maximum brightness
is not exceeded and of turning off the backlight before device removal.
The corgi backlight driver is updated to reflect these changes.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Add acceleration support in w100fb.c (i.e. ATI Imageons) for the copyarea and
fillrect operations.
Signed-off-by: Alberto Mardegan <mardy@users.sourceforge.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The current display was not saved during initialization. This leads to hard
to track console corruption, such as a misplaced cursor, which is correctible
by switching consoles. Fix this minor bug.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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It is very common to hash a dentry and then to call lookup. If we take fs
specific hash functions into account the full hash logic can get ugly.
Further full_name_hash as an inline function is almost 100 bytes on x86 so
having a non-inline choice in some cases can measurably decrease code size.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Simplifies the code, reduces the need for 4 pid hash tables, and makes the
code more capable.
In the discussions I had with Oleg it was felt that to a large extent the
cleanup itself justified the work. With struct pid being dynamically
allocated meant we could create the hash table entry when the pid was
allocated and free the hash table entry when the pid was freed. Instead of
playing with the hash lists when ever a process would attach or detach to a
process.
For myself the fact that it gave what my previous task_ref patch gave for free
with simpler code was a big win. The problem is that if you hold a reference
to struct task_struct you lock in 10K of low memory. If you do that in a user
controllable way like /proc does, with an unprivileged but hostile user space
application with typical resource limits of 1000 fds and 100 processes I can
trigger the OOM killer by consuming all of low memory with task structs, on a
machine wight 1GB of low memory.
If I instead hold a reference to struct pid which holds a pointer to my
task_struct, I don't suffer from that problem because struct pid is 2 orders
of magnitude smaller. In fact struct pid is small enough that most other
kernel data structures dwarf it, so simply limiting the number of referring
data structures is enough to prevent exhaustion of low memory.
This splits the current struct pid into two structures, struct pid and struct
pid_link, and reduces our number of hash tables from PIDTYPE_MAX to just one.
struct pid_link is the per process linkage into the hash tables and lives in
struct task_struct. struct pid is given an indepedent lifetime, and holds
pointers to each of the pid types.
The independent life of struct pid simplifies attach_pid, and detach_pid,
because we are always manipulating the list of pids and not the hash table.
In addition in giving struct pid an indpendent life it makes the concept much
more powerful.
Kernel data structures can now embed a struct pid * instead of a pid_t and
not suffer from pid wrap around problems or from keeping unnecessarily
large amounts of memory allocated.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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