linux-kernel - Re: [PATCH] gpio: rockchip: mark the GPIO controller as sleeping

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Message-ID: <CAMRc=Md0h5b=N9CqV-9L9sOtCNbiL1-y6RE0x4+w9HYXE8=pEQ@mail.gmail.com>
Date: Fri, 23 Jan 2026 20:27:06 +0100
From: Bartosz Golaszewski <brgl@...nel.org>
To: Robin Murphy <robin.murphy@....com>
Cc: Sebastian Reichel <sebastian.reichel@...labora.com>, 
	Bartosz Golaszewski <bartosz.golaszewski@....qualcomm.com>, Linus Walleij <linusw@...nel.org>, 
	Heiko Stuebner <heiko@...ech.de>, linux-gpio@...r.kernel.org, 
	linux-arm-kernel@...ts.infradead.org, linux-rockchip@...ts.infradead.org, 
	linux-kernel@...r.kernel.org, stable@...r.kernel.org, 
	Marek Szyprowski <m.szyprowski@...sung.com>
Subject: Re: [PATCH] gpio: rockchip: mark the GPIO controller as sleeping

On Fri, Jan 23, 2026 at 2:27 PM Robin Murphy <robin.murphy@....com> wrote:
>
> >>
> >> It's not a big issue for the hdmirx driver specifically, but I wonder
> >> how many more (less often tested) rockchip drivers use GPIOs from their
> >> IRQ handler.
>
> Yeah, seems this finally reached my distro kernel and now the kernel log
> on one of my boards is totally flooded from gpio_ir_recv_irq()
> (legitimately) calling gpio_get_value()... that's not really OK :/
>

This has always been a sleeping driver. The driver does not know the
firmware configuration it'll be passed and - as I explained above -
depending on the lookup flags, we may call .direction_output() and
descend into pinctrl which uses mutexes. Ideally, we'd make
GPIO-facing pinctrl operations not sleeping but this is a long-time
project and quite complex. Telling the GPIO core that it cannot sleep
is simply incorrect - even if it worked for this particular use-case -
and has an impact on paths we're choosing.

Can the GPIO reading in the gpio-ir-recv driver be done from a
high-priority workqueue by any chance? Or can we make it a threaded
interrupt?

Bartosz