linux-kernel - [PATCH] uvcvideo: Add FIX_BANDWIDTH quirk to HP Webcam found on HP Mini 5103 netbook

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 21 Jun 2011 22:07:43 +0400
From:	Kirill Smelkov <kirr@....spb.ru>
To:	Laurent Pinchart <laurent.pinchart@...asonboard.com>
Cc:	linux-uvc-devel@...ts.berlios.de, linux-media@...r.kernel.org,
	linux-kernel@...r.kernel.org, Kirill Smelkov <kirr@....spb.ru>
Subject: [PATCH] uvcvideo: Add FIX_BANDWIDTH quirk to HP Webcam found on HP Mini 5103 netbook

The camera there identifeis itself as being manufactured by Cheng Uei
Precision Industry Co., Ltd (Foxlink), and product is titled as "HP
Webcam [2 MP Fixed]".

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 bandwith (instead of
allowed for high speed 80%) I can capture two video sources -- PAL 720x576
YUV422 @25fps + NTSC 640x480 YUV422 @30fps simultaneously. Hooray!

Signed-off-by: Kirill Smelkov <kirr@....spb.ru>
---
 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,
-- 
1.7.6.rc1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/