In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

With -Wimplicit-fallthrough added to CFLAGS:

 kernel/irq/manage.c: In function ‘irq_do_set_affinity’:
 kernel/irq/manage.c:198:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
   cpumask_copy(desc->irq_common_data.affinity, mask);
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 kernel/irq/manage.c:199:2: note: here
   case IRQ_SET_MASK_OK_NOCOPY:
   ^~~~

Annotate it.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20190228213714.GA9246@embeddedor

Building with 'make W=1' complains:

  CC      kernel/irq/devres.o
kernel/irq/devres.c:104: warning: Excess function parameter 'thread_fn'
			 description in 'devm_request_any_context_irq'

Remove it.

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/31207.1552378676@turing-police

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v5.1 cycle:

  Core changes:

   - The big change this time around is the irqchip handling in the
     qualcomm pin controllers, closely coupled with the gpiochip. This
     rework, in a classic fall-between-the-chairs fashion has been
     sidestepped for too long.

     The Qualcomm IRQchips using the SPMI and SSBI transport mechanisms
     have been rewritten to use hierarchical irqchip. This creates the
     base from which I intend to gradually pull support for hierarchical
     irqchips into the gpiolib irqchip helpers to cut down on duplicate
     code.

     We have too many hacks in the kernel because people have been
     working around the missing hierarchical irqchip for years, and once
     it was there, noone understood it for a while. We are now slowly
     adapting to using it.

     This is why this pull requests include changes to MFD, SPMI,
     IRQchip core and some ARM Device Trees pertaining to the Qualcomm
     chip family. Since Qualcomm have so many chips and such large
     deployments it is paramount that this platform gets this right, and
     now it (hopefully) does.

   - Core support for pull-up and pull-down configuration, also from the
     device tree. When a simple GPIO chip supports an "off or on" pull-up
     or pull-down resistor, we provide a way to set this up using
     machine descriptors or device tree.

     If more elaborate control of pull up/down (such as resistance shunt
     setting) is required, drivers should be phased over to use pin
     control. We do not yet provide a userspace ABI for this pull
     up-down setting but I suspect the makers are going to ask for it
     soon enough. PCA953x is the first user of this new API.

   - The GPIO mockup driver has been revamped after some discussion
     improving the IRQ simulator in the process.

     The idea is to make it possible to use the mockup for both testing
     and virtual prototyping, e.g. when you do not yet have a GPIO
     expander to play with but really want to get something to develop
     code around before hardware is available. It's neat. The blackbox
     testing usecase is currently making its way into kernelci.

   - ACPI GPIO core preserves non direction flags when updating flags.

   - A new device core helper for devm_platform_ioremap_resource() is
     funneled through the GPIO tree with Greg's ACK.

  New drivers:

   - TQ-Systems QTMX86 GPIO controllers (using port-mapped I/O)

   - Gateworks PLD GPIO driver (vaccumed up from OpenWrt)

   - AMD G-Series PCH (Platform Controller Hub) GPIO driver.

   - Fintek F81804 & F81966 subvariants.

   - PCA953x now supports NXP PCAL6416.

  Driver improvements:

   - IRQ support on the Nintendo Wii (Hollywood) GPIO.

   - get_direction() support for the MVEBU driver.

   - Set the right output level on SAMA5D2.

   - Drop the unused irq trigger setting on the Spreadtrum driver.

   - Wakeup support for PCA953x.

   - A slew of cleanups in the various Intel drivers"

* tag 'gpio-v5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (110 commits)
  gpio: gpio-omap: fix level interrupt idling
  gpio: amd-fch: Set proper output level for direction_output
  x86: apuv2: remove unused variable
  gpio: pca953x: Use PCA_LATCH_INT
  platform/x86: fix PCENGINES_APU2 Kconfig warning
  gpio: pca953x: Fix dereference of irq data in shutdown
  gpio: amd-fch: Fix type error found by sparse
  gpio: amd-fch: Drop const from resource
  gpio: mxc: add check to return defer probe if clock tree NOT ready
  gpio: ftgpio: Register per-instance irqchip
  gpio: ixp4xx: Add DT bindings
  x86: pcengines apuv2 gpio/leds/keys platform driver
  gpio: AMD G-Series PCH gpio driver
  drivers: depend on HAS_IOMEM for devm_platform_ioremap_resource()
  gpio: tqmx86: Set proper output level for direction_output
  gpio: sprd: Change to use SoC compatible string
  gpio: sprd: Use SoC compatible string instead of wildcard string
  gpio: of: Handle both enable-gpio{,s}
  gpio: of: Restrict enable-gpio quirk to regulator-gpio
  gpio: davinci: use devm_platform_ioremap_resource()
  ...

Pull irqchip updates from Marc Zyngier

- Core pseudo-NMI handling code
- Allow the default irq domain to be retrieved
- A new interrupt controller for the Loongson LS1X platform
- Affinity support for the SiFive PLIC
- Better support for the iMX irqsteer driver
- NUMA aware memory allocations for GICv3
- A handful of other fixes (i8259, GICv3, PLIC)

The default irq domain allows legacy code to create irqdomain
mappings without having to track the domain it is allocating
from. Setting the default domain is a one shot, fire and forget
operation, and no effort was made to be able to retrieve this
information at a later point in time.

Newer irqdomain APIs (the hierarchical stuff) relies on both
the irqchip code to track the irqdomain it is allocating from,
as well as some form of firmware abstraction to easily identify
which piece of HW maps to which irq domain (DT, ACPI).

For systems without such firmware (or legacy platform that are
getting dragged into the 21st century), things are a bit harder.
For these cases (and these cases only!), let's provide a way
to retrieve the default domain, allowing the use of the v2 API
without having to resort to platform-specific hacks.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

gpio: updates for v5.1 - part 2

- gpio-mockup updates improving the user-space testing interface and
  adding line state tracking for correct edge interrupts
- interrupt simulator patch exposing the irq type configuration to
  users

Implement the irq_set_type() callback and call irqd_set_trigger_type()
internally so that users interested in the configured trigger type can
later retrieve it using irqd_get_trigger_type(). We only support edge
trigger types.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>

Now that the NVME driver is converted over to the calc_set() callback, the
workarounds of the original set support can be removed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-nvme@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sumit Saxena <sumit.saxena@broadcom.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Shivasharan Srikanteshwara <shivasharan.srikanteshwara@broadcom.com>
Link: https://lkml.kernel.org/r/20190216172228.689834224@linutronix.de

The interrupt affinity spreading mechanism supports to spread out
affinities for one or more interrupt sets. A interrupt set contains one or
more interrupts. Each set is mapped to a specific functionality of a
device, e.g. general I/O queues and read I/O queus of multiqueue block
devices.

The number of interrupts per set is defined by the driver. It depends on
the total number of available interrupts for the device, which is
determined by the PCI capabilites and the availability of underlying CPU
resources, and the number of queues which the device provides and the
driver wants to instantiate.

The driver passes initial configuration for the interrupt allocation via a
pointer to struct irq_affinity.

Right now the allocation mechanism is complex as it requires to have a loop
in the driver to determine the maximum number of interrupts which are
provided by the PCI capabilities and the underlying CPU resources.  This
loop would have to be replicated in every driver which wants to utilize
this mechanism. That's unwanted code duplication and error prone.

In order to move this into generic facilities it is required to have a
mechanism, which allows the recalculation of the interrupt sets and their
size, in the core code. As the core code does not have any knowledge about the
underlying device, a driver specific callback is required in struct
irq_affinity, which can be invoked by the core code. The callback gets the
number of available interupts as an argument, so the driver can calculate the
corresponding number and size of interrupt sets.

At the moment the struct irq_affinity pointer which is handed in from the
driver and passed through to several core functions is marked 'const', but for
the callback to be able to modify the data in the struct it's required to
remove the 'const' qualifier.

Add the optional callback to struct irq_affinity, which allows drivers to
recalculate the number and size of interrupt sets and remove the 'const'
qualifier.

For simple invocations, which do not supply a callback, a default callback
is installed, which just sets nr_sets to 1 and transfers the number of
spreadable vectors to the set_size array at index 0.

This is for now guarded by a check for nr_sets != 0 to keep the NVME driver
working until it is converted to the callback mechanism.

To make sure that the driver configuration is correct under all circumstances
the callback is invoked even when there are no interrupts for queues left,
i.e. the pre/post requirements already exhaust the numner of available
interrupts.

At the PCI layer irq_create_affinity_masks() has to be invoked even for the
case where the legacy interrupt is used. That ensures that the callback is
invoked and the device driver can adjust to that situation.

[ tglx: Fixed the simple case (no sets required). Moved the sanity check
  	for nr_sets after the invocation of the callback so it catches
  	broken drivers. Fixed the kernel doc comments for struct
  	irq_affinity and de-'This patch'-ed the changelog ]

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-nvme@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sumit Saxena <sumit.saxena@broadcom.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Shivasharan Srikanteshwara <shivasharan.srikanteshwara@broadcom.com>
Link: https://lkml.kernel.org/r/20190216172228.512444498@linutronix.de