kernel_optimize_test/kernel/irq
Stephen Boyd 325aa19598 genirq: Respect IRQCHIP_SKIP_SET_WAKE in irq_chip_set_wake_parent()
If a child irqchip calls irq_chip_set_wake_parent() but its parent irqchip
has the IRQCHIP_SKIP_SET_WAKE flag set an error is returned.

This is inconsistent behaviour vs. set_irq_wake_real() which returns 0 when
the irqchip has the IRQCHIP_SKIP_SET_WAKE flag set. It doesn't attempt to
walk the chain of parents and set irq wake on any chips that don't have the
flag set either. If the intent is to call the .irq_set_wake() callback of
the parent irqchip, then we expect irqchip implementations to omit the
IRQCHIP_SKIP_SET_WAKE flag and implement an .irq_set_wake() function that
calls irq_chip_set_wake_parent().

The problem has been observed on a Qualcomm sdm845 device where set wake
fails on any GPIO interrupts after applying work in progress wakeup irq
patches to the GPIO driver. The chain of chips looks like this:

     QCOM GPIO -> QCOM PDC (SKIP) -> ARM GIC (SKIP)

The GPIO controllers parent is the QCOM PDC irqchip which in turn has ARM
GIC as parent.  The QCOM PDC irqchip has the IRQCHIP_SKIP_SET_WAKE flag
set, and so does the grandparent ARM GIC.

The GPIO driver doesn't know if the parent needs to set wake or not, so it
unconditionally calls irq_chip_set_wake_parent() causing this function to
return a failure because the parent irqchip (PDC) doesn't have the
.irq_set_wake() callback set. Returning 0 instead makes everything work and
irqs from the GPIO controller can be configured for wakeup.

Make it consistent by returning 0 (success) from irq_chip_set_wake_parent()
when a parent chip has IRQCHIP_SKIP_SET_WAKE set.

[ tglx: Massaged changelog ]

Fixes: 08b55e2a92 ("genirq: Add irqchip_set_wake_parent")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-gpio@vger.kernel.org
Cc: Lina Iyer <ilina@codeaurora.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190325181026.247796-1-swboyd@chromium.org
2019-04-05 17:41:41 +02:00
..
affinity.c genirq/affinity: Remove the leftovers of the original set support 2019-02-18 11:21:29 +01:00
autoprobe.c
chip.c genirq: Respect IRQCHIP_SKIP_SET_WAKE in irq_chip_set_wake_parent() 2019-04-05 17:41:41 +02:00
cpuhotplug.c
debug.h
debugfs.c irqchip updates for Linux 5.1 2019-02-23 10:53:31 +01:00
devres.c genirq/devres: Remove excess parameter from kernel doc 2019-03-22 13:34:12 +01:00
dummychip.c
generic-chip.c
handle.c genirq: Correctly annotate implicit fall through 2019-01-15 10:40:53 +01:00
internals.h irqchip updates for Linux 5.1 2019-02-23 10:53:31 +01:00
ipi.c genirq: Fix various typos in comments 2018-12-18 14:22:28 +01:00
irq_sim.c irq/irq_sim: add irq_set_type() callback 2019-02-19 17:42:28 +01:00
irqdesc.c genirq: Initialize request_mutex if CONFIG_SPARSE_IRQ=n 2019-04-05 14:37:56 +02:00
irqdomain.c This is the bulk of GPIO changes for the v5.1 cycle: 2019-03-08 10:09:53 -08:00
Kconfig genirq/irqchip: Remove MULTI_IRQ_HANDLER as it's now obselete 2018-08-03 12:14:10 +02:00
Makefile
manage.c genirq: Mark expected switch case fall-through 2019-03-23 12:32:01 +01:00
matrix.c genirq/matrix: Improve target CPU selection for managed interrupts. 2018-11-06 23:20:13 +01:00
migration.c genirq/migration: Avoid out of line call if pending is not set 2018-06-06 15:18:20 +02:00
msi.c genirq/core: Introduce struct irq_affinity_desc 2018-12-19 11:32:08 +01:00
pm.c
proc.c genirq: Speedup show_interrupts() 2018-06-22 14:22:58 +02:00
resend.c
settings.h
spurious.c genirq: Fix various typos in comments 2018-12-18 14:22:28 +01:00
timings.c