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

[Slark Xiao]

At 2026-10-21 13:22:48, "Val Packett" <val@xxxxxxxxxxxx> wrote:
>
>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@xxxxxxxxxxxxxxx
>> Signed-off-by: Slark Xiao <slark_xiao@xxxxxxx>
>> ---
>> 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.
>
Thanks for your good suggestion. Will commit a V3 version later.

>> +#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