Re: [PATCH v2] usb: hub: Prevent hub autosuspend if usbcore.autosuspend is -1

[Roger Quadros <rogerq@ti.com>]

On 08/28/2014 12:02 AM, Greg KH wrote:
> On Wed, Aug 27, 2014 at 12:23:39PM -0700, Greg KH wrote:
>> On Wed, Aug 27, 2014 at 03:11:10PM +0300, Roger Quadros wrote:
>>> If user specifies that USB autosuspend must be disabled by module
>>> parameter "usbcore.autosuspend=-1" then we must prevent
>>> autosuspend of USB hub devices as well.
>>>
>>> commit 596d789a211d introduced in v3.8 changed the original behaivour
>>> and stopped respecting the usbcore.autosuspend parameter for hubs.
>>>
>>> Fixes: 596d789a211d "USB: set hub's default autosuspend delay as 0"
>>>
>>> Cc: [3.8+] <stable@vger.kernel.org>
>>> Signed-off-by: Roger Quadros <rogerq@ti.com>
>>> ---
>>>  drivers/usb/core/hub.c | 8 +++++++-
>>>  1 file changed, 7 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
>>> index 8a4dcbc..59b599d 100644
>>> --- a/drivers/usb/core/hub.c
>>> +++ b/drivers/usb/core/hub.c
>>> @@ -1728,8 +1728,14 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
>>>  	 * - Change autosuspend delay of hub can avoid unnecessary auto
>>>  	 *   suspend timer for hub, also may decrease power consumption
>>>  	 *   of USB bus.
>>> +	 *
>>> +	 * - If user has indicated to prevent autosuspend by passing
>>> +	 *   usbcore.autosuspend = -1 then keep autosuspend disabled.
>>>  	 */
>>> -	pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
>>> +#ifdef CONFIG_PM_RUNTIME
>>> +	if (hdev->dev.power.autosuspend_delay >= 0)
>>> +		pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
>>> +#endif
>>>  
>>>  	/*
>>>  	 * Hubs have proper suspend/resume support, except for root hubs
>>
>> Sorry, but can I have a patch that just adds the #ifdef as I already
>> have your original one in my tree.
> 
> This should be all that is needed, right?
> 
> ---------
> 
> 
> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> index 003cb6b1a6bf..46f5161c7891 100644
> --- a/drivers/usb/core/hub.c
> +++ b/drivers/usb/core/hub.c
> @@ -1732,8 +1732,10 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
>  	 * - If user has indicated to prevent autosuspend by passing
>  	 *   usbcore.autosuspend = -1 then keep autosuspend disabled.
>  	 */
> +#ifdef CONFIG_PM_RUNTIME
>  	if (hdev->dev.power.autosuspend_delay >= 0)
>  		pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
> +#endif
>  
>  	/*
>  	 * Hubs have proper suspend/resume support, except for root hubs
> 

Yes. Thanks Greg.

cheers,
-roger