The s3c2410_gpio* calls are obsolete and have been scheduled for
removal since several kernel releases. Remove them and use common
gpiolib API instead.
This patch also adds gpio_request/gpio_free call for API corectness.
It is a prerequisite for removal of the S3C24XX SoC specific
arch/arm/plat-samsung/include/gpio-fns.h header.
Tested on Micro2440-SDK.
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Use the device managed resource API for simplifying
the error/driver remove paths.
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
the platform_set_drvdata (pdev, NULL) to be set at the remove of the
driver, as we have set the platform data to led at probe.
Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Using devm_kzalloc will remove all the error checks and the frees are automatically done at the driver unload side.
Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Inside the error handling in lp5523_init_led(), there is a place that
calls to led_classdev_unregister(). When we unregister the LED drivers,
it tries to set the brightness to OFF. In this driver setting the
brightness is done through a work queue and the work queue hasn't been
initialized yet.
The result is that we trigger a WARN_ON() in the __queue_work().
The fix is to move the INIT_WORK() in front of the call to
lp5523_init_led().
Matt Renzelmann found this using a bug finding tool.
Reported-by: Matt Renzelmann <mjr@cs.wisc.edu>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
LM3556 :
The LM3556 is a 4 MHz fixed-frequency synchronous boost
converter plus 1.5A constant current driver for a high-current white LED.
Datasheet: www.national.com/ds/LM/LM3556.pdf
Tested on OMAP4430
(bryan.wu@canonical.com: use module_i2c_driver() rather than
lm3556_init/lm3556_exit for code simplicity; fixed some typo
pointed out by Rob Landley)
Signed-off-by: G.Shark Jeong <gshark.jeong@gmail.com>
Reviewed-by: Axel Lin <axel.lin@gmail.com>
Reviewed-by: Kim, Milo <Milo.Kim@ti.com>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
the ret is got the status returned by the
led_classdev_register, returning ret if the
led_classdev_register fails and returning 0
if the led_classdev_register success, can be done
by doing just "return ret" at the end.
Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
drivers/leds/led-core.c:56:6: sparse: symbol 'led_blink_setup' was not declared. Should it be static?
drivers/leds/led-triggers.c:233:6: sparse: symbol 'led_trigger_blink_setup' was not declared. Should it be static?
Reported-by: Fengguang Wu <wfg@linux.intel.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Fix led_trigger_event() to use led_set_brightness() instead of
__led_set_brightness(), so that any pending blink timer is stopped before
setting the new brightness value. Without this fix LED status may be
overridden by a pending timer.
This allows a trigger to use a mix of led_trigger_event(),
led_trigger_blink() and led_trigger_blink_oneshot() without races.
(applied over: leds: Rename led_brightness_set() to led_set_brightness())
Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Cc: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Rename leds external interface led_brightness_set() to led_set_brightness().
This is the second phase of the change to reduce confusion between the
leds internal and external interfaces that set brightness. With this change,
now the external interface is led_set_brightness(). The first phase renamed
the internal interface led_set_brightness() to __led_set_brightness().
There are no changes to the interface implementations.
Signed-off-by: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Rename leds internal interface led_set_brightness() to __led_set_brightness()
to reduce confusion between led_set_brightness() and the external interface
led_brightness_set(). led_brightness_set() cancels the timer and then calls
led_set_brightness().
Signed-off-by: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Add oneshot trigger to blink a led with configurale parameters via
sysfs.
Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Cc: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Move led_stop_software_blink() code into led_brightness_set() to ensure
software blink timer is stopped and cleared when changing trigger.
Also use led_set_brightness() instead of calling
led_cdev->brightness_set() directly to keep led_cdev->brightness
consistent with current LED status.
This ensure proper cleaning when changing triggers, as without this fix
a LED may be turned off while leaving it's led_cdev->brightness = 1,
leading to an erratic software-blink behaviour.
The problem was easy to reproduce by changing the trigger from "timer"
to "oneshot".
Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Convert ledtrig-ide-disk code to use the generic API for one-shot LED
blinking.
This patch changes slightly the behaviour of the trigger, as while the
original version kept the LED on under heavy activity, the new one keeps
a constant on-off blink at 1 / (2 * BLINK_DELAY) Hz.
(bryan.wu@canonical.com: remove 2 useless included header files)
Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Add two new functions, led_blink_set_oneshot and
led_trigger_blink_oneshot, to be used by triggers for one-shot blink of
led devices.
This is implemented extending the existing software-blink code, and uses
the same timer and handler function.
The behavior of the code is to do a blink-on, blink-off sequence when
the function is called, ignoring other calls until the sequence is
completed so that the leds keep blinking at constant rate if the
functions are called repeatedly.
This is meant to be used by drivers which needs to trigger on sporadic
event, but doesn't have clear busy/idle trigger points.
After the blink sequence the led remains off. This behavior can be
inverted setting the "invert" argument, which blink the led off, than on
and leave the led on after the sequence.
(bryan.wu@canonical.com: rebase to commit 'leds: don't disable blinking
when writing the same value to delay_on or delay_off')
Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Acked-by: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
The SYSTEM_SUSPEND_DISK system state is never used, so drop it.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge emailed kgdb dmesg fixups patches from Anton Vorontsov:
"The dmesg command appears to be broken after the printk rework. The
old logic in the kdb code makes no sense in terms of current
printk/logging storage format, and KDB simply hangs forever upon
entering 'dmesg' command.
The first patch revives the command by switching to kmsg_dumper
iterator. As a side-effect, the code is now much more simpler.
A few changes were needed in the printk.c: we needed unlocked variant
of the kmsg_dumper iterator, but these can surely wait for 3.6.
It's probably too late even for the first patch to go to 3.5, but I'll
try to convince otherwise. :-) Here we go:
- The current code is broken for sure, and has no hope to work at
all. It is a regression
- The new code works for me, and probably works for everyone else;
- If it compiles (and I urge everyone to compile-test it on your
setup), it hardly can make things worse."
* Merge emailed patches from Anton Vorontsov: (4 commits)
kdb: Switch to nolock variants of kmsg_dump functions
printk: Implement some unlocked kmsg_dump functions
printk: Remove kdb_syslog_data
kdb: Revive dmesg command
The locked variants are prone to deadlocks (suppose we got to the
debugger w/ the logbuf lock held), so let's switch to nolock variants.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If used from KDB, the locked variants are prone to deadlocks (suppose we
got to the debugger w/ the logbuf lock held).
So, we have to implement a few routines that grab no logbuf lock.
Yet we don't need these functions in modules, so we don't export them.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The function is no longer needed, so remove it.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kgdb dmesg command is broken after the printk rework. The old logic
in kdb code makes no sense in terms of current printk/logging storage
format, and KDB simply hangs forever.
This patch revives the command by switching to kmsg_dumper iterator.
The code is now much more simpler and shorter.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull late MIPS fixes from Ralf Baechle:
"This fixes a number of lose ends in the MIPS code and various bug
fixes.
Aside of dropping some patch that should not be in this pull request
everything has sat in -next for quite a while and there are no known
issues.
The biggest patch in this patch set moves the allocation of an array
that is aliased to a function (for runtime generated code) to
assembler code. This avoids an issue with certain toolchains when
building for microMIPS."
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (35 commits)
MIPS: PCI: Move fixups from __init to __devinit.
MIPS: Fix bug.h MIPS build regression
MIPS: sync-r4k: remove redundant irq operation
MIPS: smp: Warn on too early irq enable
MIPS: call set_cpu_online() on cpu being brought up with irq disabled
MIPS: call ->smp_finish() a little late
MIPS: Yosemite: delay irq enable to ->smp_finish()
MIPS: SMTC: delay irq enable to ->smp_finish()
MIPS: BMIPS: delay irq enable to ->smp_finish()
MIPS: Octeon: delay enable irq to ->smp_finish()
MIPS: Oprofile: Fix build as a module.
MIPS: BCM63XX: Fix BCM6368 IPSec clock bit
MIPS: perf: Fix build error caused by unused counters_per_cpu_to_total()
MIPS: Fix Magic SysRq L kernel crash.
MIPS: BMIPS: Fix duplicate header inclusion.
mips: mark const init data with __initconst instead of __initdata
MIPS: cmpxchg.h: Add missing include
MIPS: Malta may also be equipped with MIPS64 R2 processors.
MIPS: Fix typo multipy -> multiply
MIPS: Cavium: Fix duplicate ARCH_SPARSEMEM_ENABLE in kconfig.
...
- avoid a crash in dm-raid1 when discards coincide with mirror recovery;
- avoid discarding shared data that's still needed in dm-thin;
- don't guarantee that discarded blocks will be wiped in dm-raid1.
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Merge tag 'dm-3.5-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm
Pull device-mapper discard fixes from Alasdair G Kergon:
- avoid a crash in dm-raid1 when discards coincide with mirror
recovery;
- avoid discarding shared data that's still needed in dm-thin;
- don't guarantee that discarded blocks will be wiped in dm-raid1.
* tag 'dm-3.5-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm:
dm raid1: set discard_zeroes_data_unsupported
dm thin: do not send discards to shared blocks
dm raid1: fix crash with mirror recovery and discard
Pull pnfs/ore fixes from Boaz Harrosh:
"These are catastrophic fixes to the pnfs objects-layout that were just
discovered. They are also destined for @stable.
I have found these and worked on them at around RC1 time but
unfortunately went to the hospital for kidney stones and had a very
slow recovery. I refrained from sending them as is, before proper
testing, and surly I have found a bug just yesterday.
So now they are all well tested, and have my sign-off. Other then
fixing the problem at hand, and assuming there are no bugs at the new
code, there is low risk to any surrounding code. And in anyway they
affect only these paths that are now broken. That is RAID5 in pnfs
objects-layout code. It does also affect exofs (which was not broken)
but I have tested exofs and it is lower priority then objects-layout
because no one is using exofs, but objects-layout has lots of users."
* 'for-linus' of git://git.open-osd.org/linux-open-osd:
pnfs-obj: Fix __r4w_get_page when offset is beyond i_size
pnfs-obj: don't leak objio_state if ore_write/read fails
ore: Unlock r4w pages in exact reverse order of locking
ore: Remove support of partial IO request (NFS crash)
ore: Fix NFS crash by supporting any unaligned RAID IO
http://lists.infradead.org/pipermail/linux-mtd/2012-May/041408.htmlhttp://lists.infradead.org/pipermail/linux-mtd/2012-June/042422.html
and we finally have the fix. I am quite confident the fix is correct
because I could reproduce the problem with nandsim and verify the
fix. It was also verified by Iwo (the reporter).
I am also confident that this is OK to merge the fix so late because
this patch affects only the fixup functionality, which is not used by
most users.
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Merge tag 'upstream-3.5-rc8' of git://git.infradead.org/linux-ubifs
Pull UBIFS free space fix-up bugfix from Artem Bityutskiy:
"It's been reported already twice recently:
http://lists.infradead.org/pipermail/linux-mtd/2012-May/041408.htmlhttp://lists.infradead.org/pipermail/linux-mtd/2012-June/042422.html
and we finally have the fix. I am quite confident the fix is correct
because I could reproduce the problem with nandsim and verify the fix.
It was also verified by Iwo (the reporter).
I am also confident that this is OK to merge the fix so late because
this patch affects only the fixup functionality, which is not used by
most users."
* tag 'upstream-3.5-rc8' of git://git.infradead.org/linux-ubifs:
UBIFS: fix a bug in empty space fix-up
We can't guarantee that REQ_DISCARD on dm-mirror zeroes the data even if
the underlying disks support zero on discard. So this patch sets
ti->discard_zeroes_data_unsupported.
For example, if the mirror is in the process of resynchronizing, it may
happen that kcopyd reads a piece of data, then discard is sent on the
same area and then kcopyd writes the piece of data to another leg.
Consequently, the data is not zeroed.
The flag was made available by commit 983c7db347
(dm crypt: always disable discard_zeroes_data).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
When process_discard receives a partial discard that doesn't cover a
full block, it sends this discard down to that block. Unfortunately, the
block can be shared and the discard would corrupt the other snapshots
sharing this block.
This patch detects block sharing and ends the discard with success when
sending it to the shared block.
The above change means that if the device supports discard it can't be
guaranteed that a discard request zeroes data. Therefore, we set
ti->discard_zeroes_data_unsupported.
Thin target discard support with this bug arrived in commit
104655fd4d (dm thin: support discards).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch fixes a crash when a discard request is sent during mirror
recovery.
Firstly, some background. Generally, the following sequence happens during
mirror synchronization:
- function do_recovery is called
- do_recovery calls dm_rh_recovery_prepare
- dm_rh_recovery_prepare uses a semaphore to limit the number
simultaneously recovered regions (by default the semaphore value is 1,
so only one region at a time is recovered)
- dm_rh_recovery_prepare calls __rh_recovery_prepare,
__rh_recovery_prepare asks the log driver for the next region to
recover. Then, it sets the region state to DM_RH_RECOVERING. If there
are no pending I/Os on this region, the region is added to
quiesced_regions list. If there are pending I/Os, the region is not
added to any list. It is added to the quiesced_regions list later (by
dm_rh_dec function) when all I/Os finish.
- when the region is on quiesced_regions list, there are no I/Os in
flight on this region. The region is popped from the list in
dm_rh_recovery_start function. Then, a kcopyd job is started in the
recover function.
- when the kcopyd job finishes, recovery_complete is called. It calls
dm_rh_recovery_end. dm_rh_recovery_end adds the region to
recovered_regions or failed_recovered_regions list (depending on
whether the copy operation was successful or not).
The above mechanism assumes that if the region is in DM_RH_RECOVERING
state, no new I/Os are started on this region. When I/O is started,
dm_rh_inc_pending is called, which increases reg->pending count. When
I/O is finished, dm_rh_dec is called. It decreases reg->pending count.
If the count is zero and the region was in DM_RH_RECOVERING state,
dm_rh_dec adds it to the quiesced_regions list.
Consequently, if we call dm_rh_inc_pending/dm_rh_dec while the region is
in DM_RH_RECOVERING state, it could be added to quiesced_regions list
multiple times or it could be added to this list when kcopyd is copying
data (it is assumed that the region is not on any list while kcopyd does
its jobs). This results in memory corruption and crash.
There already exist bypasses for REQ_FLUSH requests: REQ_FLUSH requests
do not belong to any region, so they are always added to the sync list
in do_writes. dm_rh_inc_pending does not increase count for REQ_FLUSH
requests. In mirror_end_io, dm_rh_dec is never called for REQ_FLUSH
requests. These bypasses avoid the crash possibility described above.
These bypasses were improperly implemented for REQ_DISCARD when
the mirror target gained discard support in commit
5fc2ffeabb (dm raid1: support discard).
In do_writes, REQ_DISCARD requests is always added to the sync queue and
immediately dispatched (even if the region is in DM_RH_RECOVERING). However,
dm_rh_inc and dm_rh_dec is called for REQ_DISCARD resusts. So it violates the
rule that no I/Os are started on DM_RH_RECOVERING regions, and causes the list
corruption described above.
This patch changes it so that REQ_DISCARD requests follow the same path
as REQ_FLUSH. This avoids the crash.
Reference: https://bugzilla.redhat.com/837607
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
It is very common for the end of the file to be unaligned on
stripe size. But since we know it's beyond file's end then
the XOR should be preformed with all zeros.
Old code used to just read zeros out of the OSD devices, which is a great
waist. But what scares me more about this situation is that, we now have
pages attached to the file's mapping that are beyond i_size. I don't
like the kind of bugs this calls for.
Fix both birds, by returning a global zero_page, if offset is beyond
i_size.
TODO:
Change the API to ->__r4w_get_page() so a NULL can be
returned without being considered as error, since XOR API
treats NULL entries as zero_pages.
[Bug since 3.2. Should apply the same way to all Kernels since]
CC: Stable Tree <stable@kernel.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
The read-4-write pages are locked in address ascending order.
But where unlocked in a way easiest for coding. Fix that,
locks should be released in opposite order of locking, .i.e
descending address order.
I have not hit this dead-lock. It was found by inspecting the
dbug print-outs. I suspect there is an higher lock at caller that
protects us, but fix it regardless.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Do to OOM situations the ore might fail to allocate all resources
needed for IO of the full request. If some progress was possible
it would proceed with a partial/short request, for the sake of
forward progress.
Since this crashes NFS-core and exofs is just fine without it just
remove this contraption, and fail.
TODO:
Support real forward progress with some reserved allocations
of resources, such as mem pools and/or bio_sets
[Bug since 3.2 Kernel]
CC: Stable Tree <stable@kernel.org>
CC: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
In RAID_5/6 We used to not permit an IO that it's end
byte is not stripe_size aligned and spans more than one stripe.
.i.e the caller must check if after submission the actual
transferred bytes is shorter, and would need to resubmit
a new IO with the remainder.
Exofs supports this, and NFS was supposed to support this
as well with it's short write mechanism. But late testing has
exposed a CRASH when this is used with none-RPC layout-drivers.
The change at NFS is deep and risky, in it's place the fix
at ORE to lift the limitation is actually clean and simple.
So here it is below.
The principal here is that in the case of unaligned IO on
both ends, beginning and end, we will send two read requests
one like old code, before the calculation of the first stripe,
and also a new site, before the calculation of the last stripe.
If any "boundary" is aligned or the complete IO is within a single
stripe. we do a single read like before.
The code is clean and simple by splitting the old _read_4_write
into 3 even parts:
1._read_4_write_first_stripe
2. _read_4_write_last_stripe
3. _read_4_write_execute
And calling 1+3 at the same place as before. 2+3 before last
stripe, and in the case of all in a single stripe then 1+2+3
is preformed additively.
Why did I not think of it before. Well I had a strike of
genius because I have stared at this code for 2 years, and did
not find this simple solution, til today. Not that I did not try.
This solution is much better for NFS than the previous supposedly
solution because the short write was dealt with out-of-band after
IO_done, which would cause for a seeky IO pattern where as in here
we execute in order. At both solutions we do 2 separate reads, only
here we do it within a single IO request. (And actually combine two
writes into a single submission)
NFS/exofs code need not change since the ORE API communicates the new
shorter length on return, what will happen is that this case would not
occur anymore.
hurray!!
[Stable this is an NFS bug since 3.2 Kernel should apply cleanly]
CC: Stable Tree <stable@kernel.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
