Re: [PATCH v2] bus: mhi: host: pci_generic: Update the default autosuspend_delay_ms as 5000ms

[Val Packett <val@packett.cool>]

On 10/20/26 11:40 PM, Slark Xiao wrote:
> For some MHI devices in some specific scenario, the default value
> of autosuspend_delay_ms may not enough to handle last wake event.
Missing verb.. may not *be* enough
> This may lead to some unexpected problems.
Sounds vague, are there any examples of the problems? A short 
description of a concrete error message or something would be nice.
> Refer to the Qualcomm's Windows settings and we checked this with
> Quaclomm over case, Qualcomm recommend us to set this as 5000ms.

spelliiiiing. Quaclomm? :)

(also "over case" sounds odd)

> Qualcomm also suggests us to update this for all MHI devices.
> Since this setting has affected some existed kernel versions, it's
> better to be applied to stable version.
Please leave the "meta" stuff about where the commit applies outside of 
the commit message.
> Fixes: d3800c1dce24 ("bus: mhi: pci_generic: Add support for runtime PM")
> Cc: stable@vger.kernel.org
> Signed-off-by: Slark Xiao <slark_xiao@163.com>
> ---
> v2: define a autosuspend delay timeout and explain the reason
> ---
>   drivers/bus/mhi/host/pci_generic.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/bus/mhi/host/pci_generic.c b/drivers/bus/mhi/host/pci_generic.c
> index 7193a384cca4..1f52542794d7 100644
> --- a/drivers/bus/mhi/host/pci_generic.c
> +++ b/drivers/bus/mhi/host/pci_generic.c
> @@ -21,6 +21,9 @@
>   
>   #define MHI_POST_RESET_DELAY_MS 2000
>   
> +/* Add define of  initial autosuspend_delay_ms to accommodate a potential 'late wake-event' issue */

Not a very necessary comment, but if you do add it, please don't write 
things like "Add define of". This *is* the define, we're looking at it..

Also, it's not "initial" if it's not a tunable or anything, it's just 
*the* delay value.

> +#define MHI_AUTOSUSPEND_DELAY_MS 5000
> +
>   #define HEALTH_CHECK_PERIOD (HZ * 2)
>   
>   /* PCI VID definitions */
> @@ -1483,7 +1486,7 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>   
>   	/* Allow runtime suspend only if both PME from D3Hot and M3 are supported */
>   	if (pci_pme_capable(pdev, PCI_D3hot) && !(info->no_m3)) {
> -		pm_runtime_set_autosuspend_delay(&pdev->dev, 2000);
> +		pm_runtime_set_autosuspend_delay(&pdev->dev, MHI_AUTOSUSPEND_DELAY_MS);
>   		pm_runtime_use_autosuspend(&pdev->dev);
>   		pm_runtime_mark_last_busy(&pdev->dev);
>   		pm_runtime_put_noidle(&pdev->dev);


Thanks,
~val