staging:iio:ad799x fix incorrect endianness specification for buffer elements

Due to use of the IIO_ST macro, the endianness element of scan_type was
not being set.  The result is that it will default to the cpu endianness
whereas this driver will fill the buffer with big endian data.  Thus for
little endian machines, userspace will miss interpret the data.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
staging:iio:impedance:ad5933: correct error check

iio_kfifo_allocate returns NULL in case of error.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression *x;
identifier f;
statement S1,S2;
@@

*x = f(...);
 if (x) { <+... when != if (...) S1 else S2
     -ENOMEM ...+> }
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
cc: stable@vger.kernel.org
iio: Fix a buffer overflow in iio_utils.h example code

This was originally reported by Craig Markwardt on Zubair Lutfullah's
blog and Zubair forwarded it to linux-iio@vger.kernel.org. No email
address known.

The code first counted the number of enabled channels, then created an
array to hold information about them.  The code that filled this array then
stored whether a given element was enabled inside the array.  Curriously
this element was never used.  Craig's patch added a local temporary variable
to avoid the buffer overrun.  Jonathan then removed the original enabled
element of the structure as it was not needed at all.

Signed-off-by: Zubair Lutfullah <zubair.lutfullah@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
staging:iio:ad799x fix error_free_irq which was freeing an irq that may not have been requested

Only free an IRQ in error_free_irq, if it has been requested previously.

Signed-off-by: Hartmut Knaack <knaack.h@gmx.de>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Cc: stable@vger.kernel.org
iio: tsl2563: Use the correct channel2 member

Use the correct channel2 member instead of channel when dealing with sysfs
reads/writes

Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Acked-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
staging:iio:spear_adc: Add dependency on HAS_IOMEM

On archs like S390 or um this driver cannot build nor work.
Make it depend on HAS_IOMEM to bypass build failures.

drivers/staging/iio/adc/spear_adc.c: In function ‘spear_adc_probe’:
drivers/staging/iio/adc/spear_adc.c:393:2: error: implicit declaration of function ‘iounmap’ [-Werror=implicit-function-declaration

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
staging:iio:lpc32xx_adc: Add dependency on HAS_IOMEM

On archs like S390 or um this driver cannot build nor work.
Make it depend on HAS_IOMEM to bypass build failures.

drivers/built-in.o: In function `lpc32xx_adc_probe':
drivers/staging/iio/adc/lpc32xx_adc.c:149: undefined reference to `devm_ioremap'

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
xhci: Fix resume issues on Renesas chips in Samsung laptops

Don Zickus <dzickus@redhat.com> writes:

Some co-workers of mine bought Samsung laptops that had mostly usb3 ports.
Those ports did not resume correctly (the driver would timeout communicating
and fail).  This led to frustration as suspend/resume is a common use for
laptops.

Poking around, I applied the reset on resume quirk to this chipset and the
resume started working.  Reloading the xhci_hcd module had been the temporary
workaround.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Don Zickus <dzickus@redhat.com>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Cc: stable # 2.6.37
Revert "usbcore: set lpm_capable field for LPM capable root hubs"

Commit 9df89d85b407690afa46ddfbccc80bec6869971d "usbcore: set
lpm_capable field for LPM capable root hubs" was created under the
assumption that all USB host controllers should have USB 3.0 Link PM
enabled for all devices under the hosts.

Unfortunately, that's not the case.  The xHCI driver relies on knowledge
of the host hardware scheduler to calculate the LPM U1/U2 timeout
values, and it only sets lpm_capable to one for Intel host controllers
(that have the XHCI_LPM_SUPPORT quirk set).

When LPM is enabled for some Fresco Logic hosts, it causes failures with
a AgeStar 3UBT USB 3.0 hard drive dock:

Jan 11 13:59:03 sg-laptop kernel: usb 3-1: new SuperSpeed USB device number 2 using xhci_hcd
Jan 11 13:59:03 sg-laptop kernel: usb 3-1: Set SEL for device-initiated U1 failed.
Jan 11 13:59:08 sg-laptop kernel: usb 3-1: Set SEL for device-initiated U2 failed.
Jan 11 13:59:08 sg-laptop kernel: usb-storage 3-1:1.0: USB Mass Storage device detected
Jan 11 13:59:08 sg-laptop mtp-probe[613]: checking bus 3, device 2: "/sys/devices/pci0000:00/0000:00:1c.3/0000:04:00.0/usb3/3-1"
Jan 11 13:59:08 sg-laptop mtp-probe[613]: bus: 3, device: 2 was not an MTP device
Jan 11 13:59:08 sg-laptop kernel: scsi6 : usb-storage 3-1:1.0
Jan 11 13:59:13 sg-laptop kernel: usb 3-1: Set SEL for device-initiated U1 failed.
Jan 11 13:59:18 sg-laptop kernel: usb 3-1: Set SEL for device-initiated U2 failed.
Jan 11 13:59:18 sg-laptop kernel: usbcore: registered new interface driver usb-storage
Jan 11 13:59:40 sg-laptop kernel: usb 3-1: reset SuperSpeed USB device number 2 using xhci_hcd
Jan 11 13:59:41 sg-laptop kernel: usb 3-1: device descriptor read/8, error -71
Jan 11 13:59:41 sg-laptop kernel: usb 3-1: reset SuperSpeed USB device number 2 using xhci_hcd
Jan 11 13:59:46 sg-laptop kernel: usb 3-1: device descriptor read/8, error -110
Jan 11 13:59:46 sg-laptop kernel: scsi 6:0:0:0: Device offlined - not ready after error recovery
Jan 11 13:59:46 sg-laptop kernel: usb 3-1: USB disconnect, device number 2

lspci for the affected host:

04:00.0 0c03: 1b73:1000 (rev 04) (prog-if 30 [XHCI])
        Subsystem: 1043:1039
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin A routed to IRQ 19
        Region 0: Memory at dd200000 (32-bit, non-prefetchable) [size=64K]
        Capabilities: [50] Power Management version 3
                Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold-)
                Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
        Capabilities: [68] MSI: Enable- Count=1/1 Maskable- 64bit+
                Address: 0000000000000000  Data: 0000
        Capabilities: [80] Express (v1) Endpoint, MSI 00
                DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <2us, L1 <32us
                        ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
                DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
                        RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
                        MaxPayload 128 bytes, MaxReadReq 512 bytes
                DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-
                LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Latency L0 unlimited, L1 unlimited
                        ClockPM- Surprise- LLActRep- BwNot-
                LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- Retrain- CommClk+
                        ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
                LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
        Kernel driver in use: xhci_hcd
        Kernel modules: xhci_hcd

The commit was backported to stable kernels, and will need to be
reverted there as well.

Signed-off-by: Sarah Sharp <sarah.a.sharp@intel.com>
Reported-by: Sergey Galanov <sergey.e.galanov@gmail.com>
Cc: stable@vger.kernel.org
power: ds2782_battery: Typo in comment

Change missleading comment to actual shift value provided by the chip.

Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
isp1704_charger: remove useless check in isp1704_charger_probe()

Neither devm_usb_get_phy_by_phandle() nor devm_usb_get_phy() can
return a NULL result, so remove the useless !isp->phy check.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
dt: binding documentation for bq2415x charger

Add devicetree binding documentation for bq2415x charger.

Signed-off-by: Sebastian Reichel <sre@debian.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
bcache: fix BUG_ON due to integer overflow with GC_SECTORS_USED

The BUG_ON at the end of __bch_btree_mark_key can be triggered due to
an integer overflow error:

BITMASK(GC_SECTORS_USED, struct bucket, gc_mark, 2, 13);
...
SET_GC_SECTORS_USED(g, min_t(unsigned,
	     GC_SECTORS_USED(g) + KEY_SIZE(k),
	     (1 << 14) - 1));
BUG_ON(!GC_SECTORS_USED(g));

In bcache.h, the SECTORS_USED bitfield is defined to be 13 bits wide.
While the SET_ code tries to ensure that the field doesn't overflow by
clamping it to (1<<14)-1 == 16383, this is incorrect because 16383
requires 14 bits.  Therefore, if GC_SECTORS_USED() + KEY_SIZE() =
8192, the SET_ statement tries to store 8192 into a 13-bit field.  In
a 13-bit field, 8192 becomes zero, thus triggering the BUG_ON.

Therefore, create a field width constant and a max value constant, and
use those to create the bitfield and check the inputs to
SET_GC_SECTORS_USED.  Arguably the BITMASK() template ought to have
BUG_ON checks for too-large values, but that's a separate patch.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
bcache: Minor fixes from kbuild robot

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
bcache: bugfix - gc thread now gets woken when cache is full

Signed-off-by: Nicholas Swenson <nks@daterainc.com>
Revert "xhci: replace xhci_write_64() with writeq()"

This reverts commit 7dd09a1af2c7150269350aaa567a11b06e831003.

Many xHCI host controllers can only handle 32-bit addresses, and writing
64-bits at a time causes them to fail.  Rafał reports that USB devices
simply do not enumerate, and reverting this patch helps.  Branimir
reports that his host controller doesn't respond to an Enable Slot
command and dies:

[   75.576160] xhci_hcd 0000:03:00.0: Timeout while waiting for a slot
[   88.991634] xhci_hcd 0000:03:00.0: Stopped the command ring failed, maybe the host is dead
[   88.991748] xhci_hcd 0000:03:00.0: Abort command ring failed
[   88.991845] xhci_hcd 0000:03:00.0: HC died; cleaning up
[   93.985489] xhci_hcd 0000:03:00.0: Timeout while waiting for a slot
[   93.985494] xhci_hcd 0000:03:00.0: Abort the command ring, but the xHCI is dead.
[   98.982586] xhci_hcd 0000:03:00.0: Timeout while waiting for a slot
[   98.982591] xhci_hcd 0000:03:00.0: Abort the command ring, but the xHCI is dead.
[  103.979696] xhci_hcd 0000:03:00.0: Timeout while waiting for a slot
[  103.979702] xhci_hcd 0000:03:00.0: Abort the command ring, but the xHCI is dead

Signed-off-by: Sarah Sharp <sarah.a.sharp@intel.com>
Reported-by: Rafał Miłecki <zajec5@gmail.com>
Reported-by: Branimir Maksimovic <branimir.maksimovic@gmail.com>
Cc: Xenia Ragiadakou <burzalodowa@gmail.com>
KVM: return an error code in kvm_vm_ioctl_register_coalesced_mmio()

If kvm_io_bus_register_dev() fails then it returns success but it should
return an error code.

I also did a little cleanup like removing an impossible NULL test.

Cc: stable@vger.kernel.org
Fixes: 2b3c246a682c ('KVM: Make coalesced mmio use a device per zone')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
percpu_ida: fix a live lock

steal_tags only happens when free tags is more than half of the total
tags.  This is too strict and can cause live lock. I found that if one
cpu has free tags, but other cpu can't steal (thread is bound to
specific cpus), threads which want to allocate tags are always
sleeping. I found this when I run next patch, but this could happen
without it I think.

I did performance test too with null_blk. Two cases (each cpu has enough
percpu tags, or total tags are limited), no performance changes were
observed.

Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk-mq: Don't reserve a tag for flush request

Reserving a tag (request) for flush to avoid dead lock is a overkill. A
tag is valuable resource. We can track the number of flush requests and
disallow having too many pending flush requests allocated. With this
patch, blk_mq_alloc_request_pinned() could do a busy nop (but not a dead
loop) if too many pending requests are allocated and new flush request
is allocated. But this should not be a problem, too many pending flush
requests are very rare case.

I verified this can fix the deadlock caused by too many pending flush
requests.

Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: __elv_next_request() shouldn't call into the elevator if bypassing

request_queue bypassing is used to suppress higher-level function of a
request_queue so that they can be switched, reconfigured and shut
down.  A request_queue does the followings while bypassing.

* bypasses elevator and io_cq association and queues requests directly
  to the FIFO dispatch queue.

* bypasses block cgroup request_list lookup and always uses the root
  request_list.

Once confirmed to be bypassing, specific elevator and block cgroup
policy implementations can assume that nothing is in flight for them
and perform various operations which would be dangerous otherwise.

Such confirmation is acheived by short-circuiting all new requests
directly to the dispatch queue and waiting for all the requests which
were issued before to finish.  Unfortunately, while the request
allocating and draining sides were properly handled, we forgot to
actually plug the request dispatch path.  Even after bypassing mode is
confirmed, if the attached driver tries to fetch a request and the
dispatch queue is empty, __elv_next_request() would invoke the current
elevator's elevator_dispatch_fn() callback.  As all in-flight requests
were drained, the elevator wouldn't contain any request but once
bypass is confirmed we don't even know whether the elevator is even
there.  It might be in the process of being switched and half torn
down.

Frank Mayhar reports that this actually happened while switching
elevators, leading to an oops.

Let's fix it by making __elv_next_request() avoid invoking the
elevator_dispatch_fn() callback if the queue is bypassing.  It already
avoids invoking the callback if the queue is dying.  As a dying queue
is guaranteed to be bypassing, we can simply replace blk_queue_dying()
check with blk_queue_bypass().

Reported-by: Frank Mayhar <fmayhar@google.com>
References: http://lkml.kernel.org/g/1390319905.20232.38.camel@bobble.lax.corp.google.com
Cc: stable@vger.kernel.org
Tested-by: Frank Mayhar <fmayhar@google.com>

Signed-off-by: Jens Axboe <axboe@kernel.dk>