Re: [PATCH 6.12.y 1/2] spi: cadence-quadspi: fix runtime pm cleanup on probe failure/unbind

[Sasha Levin <sashal@kernel.org>]

On Fri, Aug 07, 2026 at 01:49:20PM +0200, Diogo Ivo (Schneider Electric) wrote:
> +disable_rpm:
> +	pm_runtime_put_noidle(dev);
> +	pm_runtime_dont_use_autosuspend(dev);
> +	pm_runtime_disable(dev);
>  probe_setup_failed:
>  	cqspi_controller_enable(cqspi, 0);
> -	pm_runtime_disable(dev);

This teardown order is inverted relative to upstream, and it reinstates
a bug upstream deliberately closed.

pm_runtime_dont_use_autosuspend() runs update_autosuspend(), and with
the usage count already dropped to 0 by the preceding put_noidle() and
the device still RPM_ACTIVE, that can queue a runtime suspend, i.e.
cqspi_runtime_suspend() -> clk_disable_unprepare(). The following
pm_runtime_disable() does barrier it, but control then falls through to
probe_setup_failed, which does cqspi_controller_enable(cqspi, 0) - a
register write against a potentially gated clock. That is exactly the
unclocked access 233db2cb14db ("spi: cadence-quadspi: fix unclocked
access on unbind") went out of its way to prevent.

Please mirror the upstream ordering from 5e8bb0cc72f1 ("spi:
cadence-quadspi: fix runtime pm and clock imbalance on unbind"):

	pm_runtime_disable(dev);
	pm_runtime_set_suspended(dev);
	pm_runtime_put_noidle(dev);
	pm_runtime_dont_use_autosuspend(dev);

pm_runtime_set_suspended() is missing here as well.

>  	pm_runtime_put_sync(&pdev->dev);
> +	pm_runtime_dont_use_autosuspend(&pdev->dev);
>  	pm_runtime_disable(&pdev->dev);

Same ordering problem in cqspi_remove()...

> As the history of this driver in mainline is convoluted with several
> rounds of fixes it includes the fixes from two commits, namely
> commit 5ff4d5d1af0c ("spi: cadence-quadspi: fix runtime pm disable
> imbalance on probe failure") and commit 5e8bb0cc72f1 ("spi:
> cadence-quadspi: fix runtime pm and clock imbalance on unbind").

Please split this so each patch maps to exactly one upstream commit.

> Fixes: 74b0b4cf13fc ("spi: spi-cadence-quadspi: Fix pm runtime unbalance")
> Cc: stable@vger.kernel.org

Both Fixes: tags in this series point at stable-tree commits rather than
mainline ones.

-- 
Thanks,
Sasha