Re: [PATCH V2 1/1] soc: qcom: smp2p: Add wakeup capability to SMP2P IRQ

[Matthias Kaehlcke <mka@chromium.org>]

On Mon, Aug 16, 2021 at 03:35:35PM +0530, Deepak Kumar Singh wrote:
> Remote susbsystems notify fatal crash throught smp2p interrupt.
> When modem/wifi crashes it can cause soc to come out of low power state
> and may not allow again to enter in low power state until crash is handled.
> 
> Mark smp2p interrupt wakeup capable so that interrupt handler is executed
> and remote susbsystem crash can be handled in system  resume path.
> 
> Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>
> ---
>  drivers/soc/qcom/smp2p.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/drivers/soc/qcom/smp2p.c b/drivers/soc/qcom/smp2p.c
> index 2df4883..646848b 100644
> --- a/drivers/soc/qcom/smp2p.c
> +++ b/drivers/soc/qcom/smp2p.c
> @@ -18,6 +18,7 @@
>  #include <linux/soc/qcom/smem.h>
>  #include <linux/soc/qcom/smem_state.h>
>  #include <linux/spinlock.h>
> +#include <linux/pm_wakeirq.h>
>  
>  /*
>   * The Shared Memory Point to Point (SMP2P) protocol facilitates communication
> @@ -538,9 +539,20 @@ static int qcom_smp2p_probe(struct platform_device *pdev)
>  		goto unwind_interfaces;
>  	}
>  
> +	/* Setup smp2p interrupt as wakeup source */
> +	ret = device_init_wakeup(&pdev->dev, true);
> +	if (ret)
> +		goto unwind_interfaces;
> +
> +	ret = dev_pm_set_wake_irq(&pdev->dev, irq);
> +	if (ret)
> +		goto set_wakeup_failed;
>  
>  	return 0;
>  
> +set_wakeup_failed:
> +	device_init_wakeup(&pdev->dev, false);
> +

I think you need to call dev_pm_clear_wake_irq() and
device_init_wakeup(..., false) in qcom_smp2p_remove()
to free all resources.