Re: [PATCH] i2c: tegra: Don't mark devices with pins as IRQ safe

[Mikko Perttunen <mperttunen@nvidia.com>]

On Monday, February 2, 2026 1:42 PM Mikko Perttunen wrote:
> I2C devices with associated pinctrl states (DPAUX I2C controllers)
> will change pinctrl state during runtime PM. This requires taking
> a mutex, so these devices cannot be marked as IRQ safe.
> 
> Discovered through lockdep.

Eh, I guess not lockdep, just normal lock debugging..

> 
> Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
> ---
>  drivers/i2c/busses/i2c-tegra.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
> index bec619b9af4e..4eaeb395d5db 100644
> --- a/drivers/i2c/busses/i2c-tegra.c
> +++ b/drivers/i2c/busses/i2c-tegra.c
> @@ -2047,8 +2047,11 @@ static int tegra_i2c_probe(struct platform_device *pdev)
>  	 *
>  	 * VI I2C device shouldn't be marked as IRQ-safe because VI I2C won't
>  	 * be used for atomic transfers. ACPI device is not IRQ safe also.
> +	 *
> +	 * Devices with pinctrl states cannot be marked IRQ-safe as the pinctrl
> +	 * state transitions during runtime PM require mutexes.
>  	 */
> -	if (!IS_VI(i2c_dev) && !has_acpi_companion(i2c_dev->dev))
> +	if (!IS_VI(i2c_dev) && !has_acpi_companion(i2c_dev->dev) && !i2c_dev->dev->pins)
>  		pm_runtime_irq_safe(i2c_dev->dev);
>  
>  	pm_runtime_enable(i2c_dev->dev);
> 
> ---
> base-commit: 4f938c7d3b25d87b356af4106c2682caf8c835a2
> change-id: 20260202-i2c-dpaux-irqsafe-edc04628b401
> 
>