irqchip/wpcm450: Fix memory leak in wpcm450_aic_of_init()

If of_iomap() failed, 'aic' should be freed before return. Otherwise
there is a memory leak.

Fixes: fead4dd49663 ("irqchip: Add driver for WPCM450 interrupt controller")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221115092532.1704032-1-weiyongjun@huaweicloud.com

irq: remove handle_domain_{irq,nmi}()

Now that entry code handles IRQ entry (including setting the IRQ regs)
before calling irqchip code, irqchip code can safely call
generic_handle_domain_irq(), and there's no functional reason for it to
call handle_domain_irq().

Let's cement this split of responsibility and remove handle_domain_irq()
entirely, updating irqchip drivers to call generic_handle_domain_irq().

For consistency, handle_domain_nmi() is similarly removed and replaced
with a generic_handle_domain_nmi() function which also does not perform
any entry logic.

Previously handle_domain_{irq,nmi}() had a WARN_ON() which would fire
when they were called in an inappropriate context. So that we can
identify similar issues going forward, similar WARN_ON_ONCE() logic is
added to the generic_handle_*() functions, and comments are updated for
clarity and consistency.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>

irqchip: Add driver for WPCM450 interrupt controller

The WPCM450 AIC ("Advanced Interrupt Controller") is the interrupt
controller found in the Nuvoton WPCM450 SoC and other Winbond/Nuvoton
SoCs.

The list of registers if based on the AMI vendor kernel and the
Nuvoton W90N745 datasheet.

Although the hardware supports other interrupt modes, the driver only
supports high-level interrupts at the moment, because other modes could
not be tested so far.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210406120921.2484986-7-j.neuschaefer@gmx.net