[PATCH] uvc: Enable USB autosuspend by default on uvcvideo

[PATCH] uvc: Enable USB autosuspend by default on uvcvideo

[Matthew Garrett]

We've been doing this for a while in Fedora without any complaints.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
---
 drivers/media/video/uvc/uvc_driver.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/media/video/uvc/uvc_driver.c b/drivers/media/video/uvc/uvc_driver.c
index 8bdd940..28ed5b4 100644
--- a/drivers/media/video/uvc/uvc_driver.c
+++ b/drivers/media/video/uvc/uvc_driver.c
@@ -1814,6 +1814,7 @@ static int uvc_probe(struct usb_interface *intf,
 	}
 
 	uvc_trace(UVC_TRACE_PROBE, "UVC device initialized.\n");
+	usb_enable_autosuspend(udev);
 	return 0;
 
 error:
-- 
1.7.2.3

Re: [PATCH] uvc: Enable USB autosuspend by default on uvcvideo

[Greg KH]

On Thu, Sep 16, 2010 at 02:00:04PM -0400, Matthew Garrett wrote:
> We've been doing this for a while in Fedora without any complaints.

No complaints probably, but does it actually do anything?  Last time I
measured, it didn't, but that was in the .31 kernel days.

thanks,

greg k-h

Re: [PATCH] uvc: Enable USB autosuspend by default on uvcvideo

[Matthew Garrett]

On Thu, Sep 16, 2010 at 11:45:30AM -0700, Greg KH wrote:
> On Thu, Sep 16, 2010 at 02:00:04PM -0400, Matthew Garrett wrote:
> > We've been doing this for a while in Fedora without any complaints.
> 
> No complaints probably, but does it actually do anything?  Last time I
> measured, it didn't, but that was in the .31 kernel days.

It's necessary if you want to be able to do runtime PCI power management 
on the HCD.

-- 
Matthew Garrett | mjg59@srcf.ucam.org

Re: [PATCH] uvc: Enable USB autosuspend by default on uvcvideo

[Greg KH]

On Thu, Sep 16, 2010 at 07:53:18PM +0100, Matthew Garrett wrote:
> On Thu, Sep 16, 2010 at 11:45:30AM -0700, Greg KH wrote:
> > On Thu, Sep 16, 2010 at 02:00:04PM -0400, Matthew Garrett wrote:
> > > We've been doing this for a while in Fedora without any complaints.
> > 
> > No complaints probably, but does it actually do anything?  Last time I
> > measured, it didn't, but that was in the .31 kernel days.
> 
> It's necessary if you want to be able to do runtime PCI power management 
> on the HCD.

Ok, fair enough, no objection from me.

thanks,

greg k-h

Re: [PATCH] uvc: Enable USB autosuspend by default on uvcvideo

[Laurent Pinchart]

Hi Matthew,

Thanks for the patch.

On Thursday 16 September 2010 20:00:04 Matthew Garrett wrote:
> We've been doing this for a while in Fedora without any complaints.

I'll trust you on that. If users start complaining I'll tell them who to blame 
;-)

> Signed-off-by: Matthew Garrett <mjg@redhat.com>

Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

(although, if you need to resubmit the patch for any reason, I'd rather like 
the usb_enable_autosuspend call to be before the uvc_trace call).

> ---
>  drivers/media/video/uvc/uvc_driver.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/media/video/uvc/uvc_driver.c
> b/drivers/media/video/uvc/uvc_driver.c index 8bdd940..28ed5b4 100644
> --- a/drivers/media/video/uvc/uvc_driver.c
> +++ b/drivers/media/video/uvc/uvc_driver.c
> @@ -1814,6 +1814,7 @@ static int uvc_probe(struct usb_interface *intf,
>  	}
> 
>  	uvc_trace(UVC_TRACE_PROBE, "UVC device initialized.\n");
> +	usb_enable_autosuspend(udev);
>  	return 0;
> 
>  error:

-- 
Regards,

Laurent Pinchart