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Kernel Source and devicetree for NOTHING Phone(3a) and Phone(3a)Pro
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Douglas Anderson 2f5fbc4305 irqchip/qcom-pdc: Fix phantom irq when changing between rising/falling 
We have a problem if we use gpio-keys and configure wakeups such that
we only want one edge to wake us up.  AKA:
  wakeup-event-action = <EV_ACT_DEASSERTED>;
  wakeup-source;

Specifically we end up with a phantom interrupt that blocks suspend if
the line was already high and we want wakeups on rising edges (AKA we
want the GPIO to go low and then high again before we wake up).  The
opposite is also problematic.

Specifically, here's what's happening today:
1. Normally, gpio-keys configures to look for both edges.  Due to the
   current workaround introduced in commit c3c0c2e18d ("pinctrl:
   qcom: Handle broken/missing PDC dual edge IRQs on sc7180"), if the
   line was high we'd configure for falling edges.
2. At suspend time, we change to look for rising edges.
3. After qcom_pdc_gic_set_type() runs, we get a phantom interrupt.

We can solve this by just clearing the phantom interrupt.

NOTE: it is possible that this could cause problems for a client with
very specific needs, but there's not much we can do with this
hardware.  As an example, let's say the interrupt signal is currently
high and the client is looking for falling edges.  The client now
changes to look for rising edges.  The client could possibly expect
that if the line has a short pulse low (and back high) that it would
always be detected.  Specifically no matter when the pulse happened,
it should either have tripped the (old) falling edge trigger or the
(new) rising edge trigger.  We will simply not trip it.  We could
narrow down the race a bit by polling our parent before changing
types, but no matter what we do there will still be a period of time
where we can't tell the difference between a real transition (or more
than one transition) and the phantom.

Fixes: f55c73aef8 ("irqchip/pdc: Add PDC interrupt controller for QCOM SoCs")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Tested-by: Maulik Shah <mkshah@codeaurora.org>
Reviewed-by: Maulik Shah <mkshah@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20201211141514.v4.1.I2702919afc253e2a451bebc3b701b462b2d22344@changeid
2020-12-12 10:46:02 +00:00
arch Yet two more places which invoke tracing from RCU disabled regions in the 2020-11-29 11:19:26 -08:00
block block/keyslot-manager: prevent crash when num_slots=1 2020-11-20 11:52:52 -07:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto drivers-5.10-2020-10-12 2020-10-13 13:04:41 -07:00
Documentation dt-bindings: interrupt-controller: Add binding for few Microsemi interrupt controllers 2020-12-11 14:47:49 +00:00
drivers irqchip/qcom-pdc: Fix phantom irq when changing between rising/falling 2020-12-12 10:46:02 +00:00
fs More EFI fixes for v5.10-rc: 2020-11-29 10:18:53 -08:00
include driver core: platform: Add devm_platform_get_irqs_affinity() 2020-12-11 14:47:51 +00:00
init Urgent printk fix for 5.10 2020-11-27 10:38:36 -08:00
ipc ipc: adjust proc_ipc_sem_dointvec definition to match prototype 2020-09-05 12:14:29 -07:00
kernel genirq/affinity: Add irq_update_affinity_desc() 2020-12-11 14:47:50 +00:00
lib lib/strncpy_from_user.c: Mask out bytes after NUL terminator. 2020-11-19 11:56:16 -08:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm mm: fix VM_BUG_ON(PageTail) and BUG_ON(PageWriteback) 2020-11-24 15:23:19 -08:00
net linux-can-fixes-for-5.10-20201127 2020-11-27 11:13:39 -08:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2020-11-06 17:49:34 -08:00
scripts Kbuild fixes for v5.10 2020-11-28 10:42:30 -08:00
security selinux/stable-5.10 PR 20201113 2020-11-14 12:04:02 -08:00
sound ASoC: Fixes for v5.11 2020-11-19 19:56:29 +01:00
tools perf probe: Change function definition check due to broken DWARF 2020-11-27 14:36:15 -03:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt kvm: x86/mmu: Support dirty logging for the TDP MMU 2020-10-23 03:42:13 -04:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: docs: ignore sphinx_*/ directories 2020-09-10 10:44:31 -06:00
.mailmap ARM: 2020-11-27 11:04:13 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS Samsung changes for v5.10 2020-11-13 13:16:27 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Char/misc driver fixes for 5.10-rc6 2020-11-28 10:04:36 -08:00
Makefile Linux 5.10-rc6 2020-11-29 15:50:50 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README 

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.