Re: [PATCH, RESEND] uvcvideo: Add FIX_BANDWIDTH quirk to HP Webcam found on HP Mini 5103 netbook

[Laurent Pinchart]

Hi Kirill,

On Friday 22 July 2011 16:47:22 Kirill Smelkov wrote:
>  [ Cc'ing Andrew Morton -- Andrew, could you please pick this patch, in
>    case there is no response from maintainers again? Thanks beforehand. ]
> 
> 
> Hello up there,
> 
> My first posting was 1 month ago, and a reminder ~ 2 weeks ago. All
> without a reply. v3.0 is out and they say the merge window will be
> shorter this time, so in oder not to miss it, I've decided to resend my
> patch on lowering USB periodic bandwidth allocation topic.

I'm very very sorry for missing the patch (and worse, twice :-/).

> Could this simple patch be please applied?

Yes it can. I see that Andrew already applied it to his tree. Mauro, should it 
go through there, or through your tree ? I've pushed it to my tree at 
git://linuxtv.org/pinchartl/uvcvideo.git uvcvideo-stable, so you can already 
pull.

> Thanks,
> Kirill
> 
> 
> P.S.
> 
> Referenced in the description cc62a7eb (USB: EHCI: Allow users to
> override 80% max periodic bandwidth) will be entering the mainline via
> Greg's usb tree.
> 
> ---- 8< ----
> From: Kirill Smelkov <kirr@xxxxxxxxxx>
> Subject: [PATCH] uvcvideo: Add FIX_BANDWIDTH quirk to HP Webcam found on HP
> Mini 5103 netbook
> 
> The camera there identifies itself as being manufactured by Cheng Uei
> Precision Industry Co., Ltd (Foxlink), and product is titled as "HP
> Webcam [2 MP Fixed]".

The device isn't listed in the supported devices list. Could you please send 
me its lsusb -v output ?

> I was trying to get 2 USB video capture devices to work simultaneously,
> and noticed that the above mentioned webcam always requires packet size
> = 3072 bytes per micro frame (~= 23.4 MB/s isoc bandwidth), which is far
> more than enough to get standard NTSC 640x480x2x30 = ~17.6 MB/s isoc
> bandwidth.
> 
> As there are alt interfaces with smaller MxPS
> 
>     T:  Bus=01 Lev=01 Prnt=01 Port=03 Cnt=01 Dev#=  2 Spd=480  MxCh= 0
>     D:  Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs=  1
>     P:  Vendor=05c8 ProdID=0403 Rev= 1.06
>     S:  Manufacturer=Foxlink
>     S:  Product=HP Webcam [2 MP Fixed]
>     S:  SerialNumber=200909240102
>     C:* #Ifs= 2 Cfg#= 1 Atr=80 MxPwr=500mA
>     A:  FirstIf#= 0 IfCount= 2 Cls=0e(video) Sub=03 Prot=00
>     I:* If#= 0 Alt= 0 #EPs= 1 Cls=0e(video) Sub=01 Prot=00 Driver=uvcvideo
>     E:  Ad=83(I) Atr=03(Int.) MxPS=  16 Ivl=4ms
>     I:* If#= 1 Alt= 0 #EPs= 0 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
>     I:  If#= 1 Alt= 1 #EPs= 1 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
>     E:  Ad=81(I) Atr=05(Isoc) MxPS= 128 Ivl=125us
>     I:  If#= 1 Alt= 2 #EPs= 1 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
>     E:  Ad=81(I) Atr=05(Isoc) MxPS= 512 Ivl=125us
>     I:  If#= 1 Alt= 3 #EPs= 1 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
>     E:  Ad=81(I) Atr=05(Isoc) MxPS=1024 Ivl=125us
>     I:  If#= 1 Alt= 4 #EPs= 1 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
>     E:  Ad=81(I) Atr=05(Isoc) MxPS=1536 Ivl=125us
>     I:  If#= 1 Alt= 5 #EPs= 1 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
>     E:  Ad=81(I) Atr=05(Isoc) MxPS=2048 Ivl=125us
>     I:  If#= 1 Alt= 6 #EPs= 1 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
>     E:  Ad=81(I) Atr=05(Isoc) MxPS=2688 Ivl=125us
>     I:  If#= 1 Alt= 7 #EPs= 1 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo
>     E:  Ad=81(I) Atr=05(Isoc) MxPS=3072 Ivl=125us
> 
> UVC_QUIRK_FIX_BANDWIDTH helps here and NTSC video can be served with
> MxPS=2688 i.e. 20.5 MB/s isoc bandwidth.
> 
> In terms of microframe time allocation, before the quirk NTSC video
> required 60 usecs / microframe and 53 usecs / microframe after.
> 
> 
> P.S.
> 
> Now with tweaked ehci-hcd to allow up to 90% isoc bandwidth (cc62a7eb
> "USB: EHCI: Allow users to override 80% max periodic bandwidth") I can
> capture two video sources -- PAL 720x576 YUV422 @25fps + NTSC 640x480
> YUV422 @30fps simultaneously.  Hooray!
> 
> Signed-off-by: Kirill Smelkov <kirr@xxxxxxxxxx>

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

> ---
>  drivers/media/video/uvc/uvc_driver.c |    9 +++++++++
>  1 files changed, 9 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/media/video/uvc/uvc_driver.c
> b/drivers/media/video/uvc/uvc_driver.c index b6eae48..f633700 100644
> --- a/drivers/media/video/uvc/uvc_driver.c
> +++ b/drivers/media/video/uvc/uvc_driver.c
> @@ -2130,6 +2130,15 @@ static struct usb_device_id uvc_ids[] = {
>  	  .bInterfaceProtocol	= 0,
>  	  .driver_info 		= UVC_QUIRK_PROBE_MINMAX
> 
>  				| UVC_QUIRK_BUILTIN_ISIGHT },
> 
> +	/* Foxlink ("HP Webcam" on HP Mini 5103) */
> +	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
> +				| USB_DEVICE_ID_MATCH_INT_INFO,
> +	  .idVendor		= 0x05c8,
> +	  .idProduct		= 0x0403,
> +	  .bInterfaceClass	= USB_CLASS_VIDEO,
> +	  .bInterfaceSubClass	= 1,
> +	  .bInterfaceProtocol	= 0,
> +	  .driver_info		= UVC_QUIRK_FIX_BANDWIDTH },
>  	/* Genesys Logic USB 2.0 PC Camera */
>  	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
> 
>  				| USB_DEVICE_ID_MATCH_INT_INFO,

-- 
Regards,

Laurent Pinchart
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