regulator: as3722: Make 0 a valid selector

As of commit 064d5cd110f9 (regulator: core: Fix the init of DT defined
fixed regulators) the regulator core tries to query the current voltage
of a regulator when applying constraints. This exposes a bug in the
AS3722 regulator driver which fails to read the voltage of disabled
regulators. The reason is that the hardware is programmed to a selector
of 0, but none of the voltage tables include 0 as a valid selector. The
datasheets indicate that 0 is a valid selector when the regulators are
powered off.

To fix this, add a range including selector 0 to the voltage tables.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
regulator: add regulator_can_change_voltage stub

When CONFIG_REGULATOR is not set, we cannot call
regulator_can_change_voltage() from a device driver, which results
in a build error like

video/fbdev/omap2/dss/hdmi5.c: In function 'hdmi_init_regulator':
video/fbdev/omap2/dss/hdmi5.c:149:2: error: implicit declaration of function 'regulator_can_change_voltage' [-Werror=implicit-function-declaration]

even for drivers that don't require the regulator API normally.
Such a use was recently added in the omap2+ hdmi driver.

This avoids the problem by adding a static inline function
stub in the API header, as we have for most of the other
regulator functions as well.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Mark Brown <broonie@kernel.org>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
regulator: palmas: Fix SMPS list for 0V

get_voltage_sel reads from SMPS register - if the read selector value
is 0, the SMPS is actually disabled - So, this is in addition to the
ctrl_register that may also be used to enable/disable the SMPS.

The original logic(prior to commit dbabd624d4eec50b6) used to be:
static int palmas_map_voltage_smps(struct regulator_dev *rdev,
               int min_uV, int max_uV)
<snip>
       if (min_uV == 0)
               return 0;

To handle this scenario, with the transition to regulator_list
implementation, we seem to have missed the data necessary to mark as
one of the valid entries as "0" 'disabled regulator' which results in
0 volts - So, stick with pre-existing logic.

Without this added to the list, palmas regulator driver,
on probe, attempts to setup constraints and in the case of
OMAP5uEVM, SMPS9 (which is mapped for 2v1 audio supply) fails in
regulator_list_voltage_linear_range mapping of '0', and as a fall back
of constraints not being applied, the entire regulator list is not
enumerated due to assumption that something system wide has gone bad
on with the PMIC.

Fixes: dbabd624d4eec50b6 ("regulator: palmas: Reemove open coded functions with helper functions")
Reported-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
spi/pxa2xx: change default supported DMA burst size to 1

This is to fix the SPI DMA transfer failure for speed less than 1M.
If using current DMA burst size setting (16), the Rx data bytes are
invalid due to each data byte is multiplied according to the burst
size setting.

Let's said supposedly we shall receive the following 18 bytes of data:
01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18
Instead, the data bytes received consist of "16 bytes of '01' +
2 bytes of '02'" :
01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 02 02

Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
random: fix nasty entropy accounting bug

Commit 0fb7a01af5b0 "random: simplify accounting code", introduced in
v3.15, has a very nasty accounting problem when the entropy pool has
has fewer bytes of entropy than the number of requested reserved
bytes.  In that case, "have_bytes - reserved" goes negative, and since
size_t is unsigned, the expression:

       ibytes = min_t(size_t, ibytes, have_bytes - reserved);

... does not do the right thing.  This is rather bad, because it
defeats the catastrophic reseeding feature in the
xfer_secondary_pool() path.

It also can cause the "BUG: spinlock trylock failure on UP" for some
kernel configurations when prandom_reseed() calls get_random_bytes()
in the early init, since when the entropy count gets corrupted,
credit_entropy_bits() erroneously believes that the nonblocking pool
has been fully initialized (when in fact it is not), and so it calls
prandom_reseed(true) recursively leading to the spinlock BUG.

The logic is *not* the same it was originally, but in the cases where
it matters, the behavior is the same, and the resulting code is
hopefully easier to read and understand.

Fixes: 0fb7a01af5b0 "random: simplify accounting code"
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Greg Price <price@mit.edu>
Cc: stable@vger.kernel.org  #v3.15
Revert "offb: Add palette hack for little endian"

This reverts commit e1edf18b20076da83dd231dbd2146cbbc31c0b14.

This patch was a misguided attempt at fixing offb for LE ppc64
kernels on BE qemu but is just wrong ... it breaks real LE/LE
setups, LE with real HW, and existing mixed endian systems
that did the fight thing with the appropriate device-tree
property. Bad reviewing on my part, sorry.

The right fix is to either make qemu change its endian when
the guest changes endian (working on that) or to use the
existing foreign endian support.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org> [v3.13+]
---
regulator: ltc3589: Use of_get_child_by_name

of_find_node_by_name() walks the allnodes list, and can thus walk
outside of the parent node. Use of_get_child_by_name() instead.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Merge remote-tracking branch 'regulator/fix/core' into regulator-linus
Merge remote-tracking branches 'regulator/fix/as3722', 'regulator/fix/ltc3589' and 'regulator/fix/palmas' into regulator-linus
of/platform: Fix microblaze build failure

Commit bf5db2f (microblaze: Use generic device.h) removes the
microblaze specific pdev_archdata and dma_mask.

At the same time, commit 591c1ee (of: configure the platform
device dma parameters) initializes the just removed field.
This causes all microblaze builds to fail.

Drop the unnecessary initialization.

Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Rob Herring <robh@kernel.org>
of: avoid format string parsing in kobject names

This makes sure a format string cannot leak into the kobject name that
is constructed. (And splits the >80 character line.)

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Rob Herring <robh@kernel.org>
OF: fix of_find_node_by_path() assumption that of_allnodes is root

of_find_node_by_path() is borked because of_allnodes is not guaranteed to
contain the root of the tree after using any of the dynamic update functions
because some other nodes ends up as of_allnodes.

Fixes: c22e650e66b8 of: Make of_find_node_by_path() handle /aliases
Reported-by: pantelis.antoniou@konsulko.com
Signed-off-by: Frank Rowand <frank.rowand@sonymobile.com>
Signed-off-by: Rob Herring <robh@kernel.org>
epoll: fix use-after-free in eventpoll_release_file

This fixes use-after-free of epi->fllink.next inside list loop macro.
This loop actually releases elements in the body.  The list is
rcu-protected but here we cannot hold rcu_read_lock because we need to
lock mutex inside.

The obvious solution is to use list_for_each_entry_safe().  RCU-ness
isn't essential because nobody can change this list under us, it's final
fput for this file.

The bug was introduced by ae10b2b4eb01 ("epoll: optimize EPOLL_CTL_DEL
using rcu")

Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Reported-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Stable <stable@vger.kernel.org> # 3.13+
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Jason Baron <jbaron@akamai.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge tag 'spi-v3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi fix from Mark Brown:
 "A single bugfix from the merge window, fixing an issue with DMA at
  slow speeds on Intel hardware"

* tag 'spi-v3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi/pxa2xx: change default supported DMA burst size to 1
Merge tag 'regulator-v3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator

Pull regulator fixes from Mark Brown:
 "A few small fixes:

   - Fixes for bugs in Palmas and as3722 exposed by recent changes in
     the core - the drivers weren't allowing the current configuration
     to be read sometimes.
   - Provide a stub for regulator_can_change_voltage() for !REGULATOR.
   - Make sure ltc3589 only looks at its child nodes in the device tree
     rather than searching the whole tree"

* tag 'regulator-v3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: ltc3589: Use of_get_child_by_name
  regulator: palmas: Fix SMPS list for 0V
  regulator: add regulator_can_change_voltage stub
  regulator: as3722: Make 0 a valid selector
Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random

Pull randomness bugfix from Ted Ts'o:
 "random: fix entropy accounting bug introduced in v3.15"

* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  random: fix nasty entropy accounting bug
Merge tag 'dt-fixes-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull device tree fixes from Rob Herring:
 - fix microblaze compiling due to conflicting merge window changes
 - a fix in of_attach_node due to of_find_node_by_path changes
 - prevent format strings in DT kobject names

* tag 'dt-fixes-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  OF: fix of_find_node_by_path() assumption that of_allnodes is root
  of: avoid format string parsing in kobject names
  of/platform: Fix microblaze build failure
ARM: mm: cache-l2x0: Add base address argument to write_sec callback

For certain platforms (e.g. Exynos) it is necessary to read back some
values from registers before they can be written (i.e. SMC calls that
set multiple registers per call), so base address of L2C controller is
needed for .write_sec operation. This patch adds base argument to
.write_sec callback so that its implementation can also access registers
directly.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
ARM: Get outer cache .write_sec callback from mach_desc only if not NULL

Certain platforms (i.e. Exynos) might need to set .write_sec callback
from firmware initialization which is happenning in .init_early callback
of machine descriptor. However current code will overwrite the pointer
with whatever is present in machine descriptor, even though it can be
already set earlier. This patch fixes this by making the assignment
conditional, depending on whether current .write_sec callback is NULL.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
ARM: mm: cache-l2x0: Use l2c_write_sec() for LATENCY_CTRL registers

According to the documentation, TAG_LATENCY_CTRL and DATA_LATENCY_CTRL
registers of L2C-310 can be written only in secure mode, so
l2c_write_sec() should be used to change them, instead of plain
writel_relaxed().

Signed-off-by: Tomasz Figa <t.figa@samsung.com>