Re: [PATCH v1 3/3] usb: typec: fusb302: Switch to threaded interrupt handler
From: Hans de Goede <hansg@kernel.org>
Date: 2026-01-08 08:32:58
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linux-devicetree, linux-rockchip, linux-usb, lkml
Hi, On 8-Jan-26 07:58, Anand Moon wrote:
Hi Hans, On Wed, 7 Jan 2026 at 16:22, Hans de Goede [off-list ref] wrote:quoted
Hi, On 7-Jan-26 10:52, 张永波 wrote:quoted
quoted
Still ideally we would solve this in another way then switching to a threaded IRQ handler. As the commit message of the mei-vsc fix mentions the root cause of these errors is typically an interrupt chip driver which uses IRQF_NO_THREAD disabling the auto threading of all interrupt handlers in RT mode. So the first question here would be to see if that flag is used in the interrupt chip and if yes, is that flag really necessary ?This is very similar to the issue addressed in commit 24b176d8827d ("drm/msm/dsi: Remove spurious IRQF_ONESHOT flag"). The IRQF_ONESHOT flag is preventing forced threading here. In irq_setup_forced_threading(), the conversion to threaded interrupts is explicitly skipped if any of the IRQF_NO_THREAD, IRQF_PERCPU, or IRQF_ONESHOT flags are present. In this case, IRQF_ONESHOT appears to be the reason.Ah, well the code effectively does its own IRQF_ONESHOT handling, since it needs to do its own threaded-irq like handling for suspend/resume reasons. It disables the IRQ when it fires and then only re-enables it once the work has done processing the IRQ. So it should be perfectly safe to drop the IRQF_ONESHOT flag.Yes, the warning disappearsquoted
If that also works to resolve the lockdep issue that would be the preferred way of fixing this IMHO.After applying these changes, the device initially triggered a hard reset; And the board reboots. I need to find another way to fix this warning.
Hmm, I guess that without the oneshot flag fusb302_irq_intn() might trigger a second time before it disables the IRQ causing an IRQ enable unbalance issue. So lets just go with your original fix of moving this to a threaded IRQ handler. Regards, Hans