gpio_ensure_requested() has been introduced in Feb. 2008 by commit
d2876d08 to force users of the GPIO API to explicitly request GPIOs
before using them.

Hopefully by now all GPIOs are correctly requested and this extra check
can be omitted ; in any case the GPIO maintainers won't feel bad if
machines start failing after 6 years of warnings.

This patch removes that function from the dark ages.
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

An iterator variable cannot be NULL in its loop.
Reported-by: NJulia Lawall <julia.lawall@lip6.fr>
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Both functions were introduced to let gpio drivers request their own
gpio pins. Without exporting the functions, this can however only be
used by gpio drivers built into the kernel.

Secondary impact is that the functions can not currently be used by
platform initialization code associated with the gpio-pca953x driver.
This code permits auto-export of gpio pins through platform data, but
if this functionality is used, the module can no longer be unloaded due
to the problem solved with the introduction of gpiochip_request_own_desc
and gpiochip_free_own_desc.

Export both function so they can be used from modules and from
platform initialization code.
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

gpio_ensure_requested() only makes sense when using the integer-based
GPIO API, so make sure it is called from there instead of the gpiod
API which we know cannot be called with a non-requested GPIO anyway.

The uses of gpio_ensure_requested() in the gpiod API were kind of
out-of-place anyway, so putting them in gpio-legacy.c helps clearing the
code.

Actually, considering the time this ensure_requested mechanism has been
around, maybe we should just turn this patch into "remove
gpio_ensure_requested()" if we know for sure that no user depend on it
anymore?
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

gpio_lock/unlock_as_irq() are working with (chip, offset) arguments and
are thus not using the old integer namespace. Therefore, there is no
reason to have gpiod variants of these functions working with
descriptors, especially since the (chip, offset) tuple is more suitable
to the users of these functions (GPIO drivers, whereas GPIO descriptors
are targeted at GPIO consumers).
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

As GPIO descriptors are not going to remain unique anymore, having this
function public is not safe. Restrain its use to gpiolib since we have
no user outside of it.
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

For some reason gpiochip_export() would invalidate all the descriptors
of a chip if exporting it to sysfs failed. This does not appear as
necessary. Remove that part of the code.

While we are at it, add a note about the non-safety of temporarily
releasing a spinlock in the middle of the loop that protects its
iterator, and explain why this is done.
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

of_get_named_gpio_flags() has been made gpiolib-private by commit
f01d9075, but its EXPORT statement has not been removed. Fix this.
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The gpio include file and the gpio documentation declare and document
GPIOF_ACTIVE_LOW as one of the flags to be passed to gpio_request_one
and related functions. However, the flag is not evaluated or used.

This can cause problems in at least two areas: First, the same API can
be used to auto-export pins to user space. The missing support for
GPIOF_ACTIVE_LOW results in unexpected behavior for such auto-exported
pins. Second, the requested gpio pin can be convered for use by
gpiod functions with gpio_to_desc(). While gpio API functions do not
support GPIOF_ACTIVE_LOW, gpiod functions do, which again results in
unexpected behavior.

Check the flag in gpio_request_one and set the gpio internal flag
FLAG_ACTIVE_LOW if it is set to address those problems.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The Zynq GPIO controller does not disable the interrupt detection when the
interrupt is masked and only disables the propagation of the interrupt. This
means when the controller detects an interrupt condition while the interrupt is
logically disabled (and masked) it will propagate the recorded interrupt event
once the interrupt is enabled. This will cause the interrupt consumer to see
spurious interrupts to prevent this first make sure that the interrupt is not
asserted and then enable it.

E.g. when a interrupt is requested with request_irq() it will be configured
according to the requested type (edge/level triggered, etc.) after that it will
be enabled. But the detection circuit might have already registered a false
interrupt before the interrupt type was correctly configured and once the
interrupt is unmasked this false interrupt will be propagated and the interrupt
handler for the just request interrupt will called.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

As we start to decomission the return value from gpiochip_remove()
the compilers emit warnings due to the function being tagged
__must_check. So drop this until we remove the return value
altogether.

Cc: Abdoulaye Berthe <berthe.ab@gmail.com>
Suggested-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Signed-off-by: Nabdoulaye berthe <berthe.ab@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Add gpio-zynq bindings documentation.
Signed-off-by: NHarini Katakam <harinik@xilinx.com>
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Add support for GPIO controller used by Xilinx Zynq.

v3 changes:
 - Use linux/gpio/driver.h instead of linux/gpio.h
 - Make irq a local variable in probe

v2 changes:
 - convert to pm_runtime_force_(suspend|resume)
 - add pm_runtime_set_active in probe()
 - also (un)prepare clocks when they are dis-/enabled
 - add some missing calls to pm_runtime_get()
 - use pm_runtime_put() instead of sync variant
 - remove gpio chip in driver remove()
 - remove redundant type casts
 - directly use IO helpers
 - use BIT macro to set/clear bits
 - migrate to GPIOLIB_IRQCHIP
Signed-off-by: NHarini Katakam <harinik@xilinx.com>
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Following is the debug output (only a few examples) before and after
the patch.

$ dmesg | grep of_get_named_gpiod_flags

Before:
of_get_named_gpiod_flags: can't parse gpios property
 of node '/mmc@12220000[0]'
of_get_named_gpiod_flags exited with status 0

After:
of_get_named_gpiod_flags: can't parse 'wp-gpios' property
 of node '/mmc@12220000[0]'
of_get_named_gpiod_flags: parsed 'gpios' property of node
 '/gpio-keys/power[0]' - status (0)
Signed-off-by: NTushar Behera <tushar.b@samsung.com>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The old integer GPIO interface is, in effect, a privileged user of the
gpiod interface. Reflect this fact further by moving legacy GPIO support
into its own source file. This makes the code clearer and will allow us
to disable legacy GPIO support in the (far) future.
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

sysfs support is currently entangled within the core GPIO support, while
it should relly just be a (privileged) user of the integer GPIO API.
This patch is a first step towards making the gpiolib code more readable
by splitting it into logical parts.

Move all sysfs support to their own source file, and share static
members of gpiolib that need to be in the private gpiolib.h file. In
the future we will want to put some of them back into gpiolib.c, but this
first patch let us at least identify them.
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Compiling out GPIO labels results in a space gain so small that it can
hardly be justified. Labels can also be useful for printing debug
messages, so always keep them around.
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The GPIO OMAP driver didn't have a consistent naming scheme for
all its functions. Some of them had an omap prefix while others
didn't. There are many advantages on having a separate namespace
for driver functions so let's add an "omap" prefix to all of them.
Signed-off-by: NJavier Martinez Canillas <jmartinez@softcrates.net>
Acked-by: NKevin Hilman <khilman@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The <linux/irqchip/chained_irq.h> header is already included
when selecting GPIOLIB_IRQCHIP so there is no need to do it
in the driver. This is a left over from commit fb655f57
("gpio: omap: convert driver to use gpiolib irqchip").
Signed-off-by: NJavier Martinez Canillas <jmartinez@softcrates.net>
Acked-by: NKevin Hilman <khilman@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

GPIO irqchips assign to the cascaded IRQs their own lock class
in order to avoid warnings about lockdep recursions since that
allow the lockdep core to keep track of things.

Since commit e45d1c80 ("gpio: put GPIO IRQs into their own lock class")
there is no need to do this in a driver if it's using the GPIO
irqchip helpers since gpiolib already assigns a lockdep class.
Signed-off-by: NJavier Martinez Canillas <jmartinez@softcrates.net>
Acked-by: NKevin Hilman <khilman@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Removal of null pointer checks that could never happen

This was found using a static code analysis program called cppcheck
Signed-off-by: NRickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Removal of null pointer checks that could never happen

This was found using a static code analysis program called cppcheck
Signed-off-by: NRickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The driver was not checking the return value from gpiochip_add()
properly, so add a bail-out check.
Reported-by: NRickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

While it will be clamped to bool by gpiolib, let's make this sane
in the driver as well.
Signed-off-by: NJürg Billeter <j@bitron.ch>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

pxa_gpio_probe() has some issues supporting the gpio0 and gpio1
interrupts under device-tree - it never actually sets up the chain
handler to get interrupts on edge detect for GPIO0 and GPIO1.
Signed-off-by: NAndrew Ruder <andrew.ruder@elecsyscorp.com>
Acked-by: NHaojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Make of_device_id array const, because all OF functions handle
it as const.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NNeil Zhang <zhangwm@marvell.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Make of_device_id array const, because all OF functions handle
it as const.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Acked-By: NRoland Stigge <stigge@antcom.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This switches the Intel MID GPIO driver over to using the gpiolib
irqchip helpers in the gpiolib core.

Cc: xinhui.pan <xinhuiX.pan@intel.com>
Acked-by: NDavid Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This switches the STMPE driver to use the gpiolib irqchip
helpers.
Tested-by: NSilvio Fricke <silvio.fricke@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Pull networking fixes from David Miller:

 1) Fix checksumming regressions, from Tom Herbert.

 2) Undo unintentional permissions changes for SCTP rto_alpha and
    rto_beta sysfs knobs, from Denial Borkmann.

 3) VXLAN, like other IP tunnels, should advertize it's encapsulation
    size using dev->needed_headroom instead of dev->hard_header_len.
    From Cong Wang.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  net: sctp: fix permissions for rto_alpha and rto_beta knobs
  vxlan: Checksum fixes
  net: add skb_pop_rcv_encapsulation
  udp: call __skb_checksum_complete when doing full checksum
  net: Fix save software checksum complete
  net: Fix GSO constants to match NETIF flags
  udp: ipv4: do not waste time in __udp4_lib_mcast_demux_lookup
  vxlan: use dev->needed_headroom instead of dev->hard_header_len
  MAINTAINERS: update cxgb4 maintainer

Pull more clock framework updates from Mike Turquette:
 "This contains the second half the of the clk changes for 3.16.

  They are simply fixes and code refactoring for the OMAP clock drivers.
  The sunxi clock driver changes include splitting out the one
  mega-driver into several smaller pieces and adding support for the A31
  SoC clocks"

* tag 'clk-for-linus-3.16-part2' of git://git.linaro.org/people/mike.turquette/linux: (25 commits)
  clk: sunxi: document PRCM clock compatible strings
  clk: sunxi: add PRCM (Power/Reset/Clock Management) clks support
  clk: sun6i: Protect SDRAM gating bit
  clk: sun6i: Protect CPU clock
  clk: sunxi: Rework clock protection code
  clk: sunxi: Move the GMAC clock to a file of its own
  clk: sunxi: Move the 24M oscillator to a file of its own
  clk: sunxi: Remove calls to clk_put
  clk: sunxi: document new A31 USB clock compatible
  clk: sunxi: Implement A31 USB clock
  ARM: dts: OMAP5/DRA7: use omap5-mpu-dpll-clock capable of dealing with higher frequencies
  CLK: TI: dpll: support OMAP5 MPU DPLL that need special handling for higher frequencies
  ARM: OMAP5+: dpll: support Duty Cycle Correction(DCC)
  CLK: TI: clk-54xx: Set the rate for dpll_abe_m2x2_ck
  CLK: TI: Driver for DRA7 ATL (Audio Tracking Logic)
  dt:/bindings: DRA7 ATL (Audio Tracking Logic) clock bindings
  ARM: dts: dra7xx-clocks: Correct name for atl clkin3 clock
  CLK: TI: gate: add composite interface clock to OMAP2 only build
  ARM: OMAP2: clock: add DT boot support for cpufreq_ck
  CLK: TI: OMAP2: add clock init support
  ...

Pull NVMe update from Matthew Wilcox:
 "Mostly bugfixes again for the NVMe driver.  I'd like to call out the
  exported tracepoint in the block layer; I believe Keith has cleared
  this with Jens.

  We've had a few reports from people who're really pounding on NVMe
  devices at scale, hence the timeout changes (and new module
  parameters), hotplug cpu deadlock, tracepoints, and minor performance
  tweaks"

[ Jens hadn't seen that tracepoint thing, but is ok with it - it will
  end up going away when mq conversion happens ]

* git://git.infradead.org/users/willy/linux-nvme: (22 commits)
  NVMe: Fix START_STOP_UNIT Scsi->NVMe translation.
  NVMe: Use Log Page constants in SCSI emulation
  NVMe: Define Log Page constants
  NVMe: Fix hot cpu notification dead lock
  NVMe: Rename io_timeout to nvme_io_timeout
  NVMe: Use last bytes of f/w rev SCSI Inquiry
  NVMe: Adhere to request queue block accounting enable/disable
  NVMe: Fix nvme get/put queue semantics
  NVMe: Delete NVME_GET_FEAT_TEMP_THRESH
  NVMe: Make admin timeout a module parameter
  NVMe: Make iod bio timeout a parameter
  NVMe: Prevent possible NULL pointer dereference
  NVMe: Fix the buffer size passed in GetLogPage(CDW10.NUMD)
  NVMe: Update data structures for NVMe 1.2
  NVMe: Enable BUILD_BUG_ON checks
  NVMe: Update namespace and controller identify structures to the 1.1a spec
  NVMe: Flush with data support
  NVMe: Configure support for block flush
  NVMe: Add tracepoints
  NVMe: Protect against badly formatted CQEs
  ...

Commit 3fd091e7 ("[SCTP]: Remove multiple levels of msecs
to jiffies conversions.") has silently changed permissions for
rto_alpha and rto_beta knobs from 0644 to 0444. The purpose of
this was to discourage users from tweaking rto_alpha and
rto_beta knobs in production environments since they are key
to correctly compute rtt/srtt.

RFC4960 under section 6.3.1. RTO Calculation says regarding
rto_alpha and rto_beta under rule C3 and C4:

  [...]
  C3)  When a new RTT measurement R' is made, set

       RTTVAR <- (1 - RTO.Beta) * RTTVAR + RTO.Beta * |SRTT - R'|

       and

       SRTT <- (1 - RTO.Alpha) * SRTT + RTO.Alpha * R'

       Note: The value of SRTT used in the update to RTTVAR
       is its value before updating SRTT itself using the
       second assignment. After the computation, update
       RTO <- SRTT + 4 * RTTVAR.

  C4)  When data is in flight and when allowed by rule C5
       below, a new RTT measurement MUST be made each round
       trip. Furthermore, new RTT measurements SHOULD be
       made no more than once per round trip for a given
       destination transport address. There are two reasons
       for this recommendation: First, it appears that
       measuring more frequently often does not in practice
       yield any significant benefit [ALLMAN99]; second,
       if measurements are made more often, then the values
       of RTO.Alpha and RTO.Beta in rule C3 above should be
       adjusted so that SRTT and RTTVAR still adjust to
       changes at roughly the same rate (in terms of how many
       round trips it takes them to reflect new values) as
       they would if making only one measurement per
       round-trip and using RTO.Alpha and RTO.Beta as given
       in rule C3. However, the exact nature of these
       adjustments remains a research issue.
  [...]

While it is discouraged to adjust rto_alpha and rto_beta
and not further specified how to adjust them, the RFC also
doesn't explicitly forbid it, but rather gives a RECOMMENDED
default value (rto_alpha=3, rto_beta=2). We have a couple
of users relying on the old permissions before they got
changed. That said, if someone really has the urge to adjust
them, we could allow it with a warning in the log.

Fixes: 3fd091e7 ("[SCTP]: Remove multiple levels of msecs to jiffies conversions.")
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Tom Herbert says:

====================
Fixes related to some recent checksum modifications.

- Fix GSO constants to match NETIF flags
- Fix logic in saving checksum complete in __skb_checksum_complete
- Call __skb_checksum_complete from UDP if we are checksumming over
  whole packet in order to save checksum.
- Fixes to VXLAN to work correctly with checksum complete
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Call skb_pop_rcv_encapsulation and postpull_rcsum for the Ethernet
header to work properly with checksum complete.
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This function is used by UDP encapsulation protocols in RX when
crossing encapsulation boundary. If ip_summed is set to
CHECKSUM_UNNECESSARY and encapsulation is not set, change to
CHECKSUM_NONE since the checksum has not been validated within the
encapsulation. Clears csum_valid by the same rationale.
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In __udp_lib_checksum_complete check if checksum is being done over all
the data (len is equal to skb->len) and if it is call
__skb_checksum_complete instead of __skb_checksum_complete_head. This
allows checksum to be saved in checksum complete.
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Geert reported issues regarding checksum complete and UDP.
The logic introduced in commit 7e3cead5
("net: Save software checksum complete") is not correct.

This patch:
1) Restores code in __skb_checksum_complete_header except for setting
   CHECKSUM_UNNECESSARY. This function may be calculating checksum on
   something less than skb->len.
2) Adds saving checksum to __skb_checksum_complete. The full packet
   checksum 0..skb->len is calculated without adding in pseudo header.
   This value is saved in skb->csum and then the pseudo header is added
   to that to derive the checksum for validation.
3) In both __skb_checksum_complete_header and __skb_checksum_complete,
   set skb->csum_valid to whether checksum of zero was computed. This
   allows skb_csum_unnecessary to return true without changing to
   CHECKSUM_UNNECESSARY which was done previously.
4) Copy new csum related bits in __copy_skb_header.
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>