View source for Em28xx devices

This article discusses some [[USB]] interface chipset families produced by [[EMPIA Technology|EMPIA]], and, in addition, addresses the driver that support these chips.

==How to compile the latest em28xx driver?==
* See section [http://www.linuxtv.org/v4lwiki/index.php/How_to_build_from_Mercurial How o build from Mercurial]

==Firmware==
===Information===
* See section [http://www.linuxtv.org/wiki/index.php/Xceive_XC3028/XC2028#Firmware_Information Firmware Information in Xceive XC3028/XC2028 page]<br>

===How to get it?===
* See section [http://www.linuxtv.org/wiki/index.php/Xceive_XC3028/XC2028#How_to_Obtain_the_Firmware How to Obtain the Firmware in Xceive XC3028/XC2028 page]

=== Error: unable to open firmware v4l-cx25840.fw ===
==== Manually Extracting and Installing the Firmware ====
  cd /tmp
  shell> wget --user=wtv --password=Support07! ftp://ftp.hauppauge.com/Support/PVR150/Beta/070206%20amity2%202.0.48.25037.prerelease.zip
  shell> unzip "070206 amity2 2.0.48.25037.prerelease.zip"
  shell> cp HcwMakoC.ROM /lib/firmware/v4l-cx25840.fw

Based on [http://ivtvdriver.org/index.php/Firmware ivtv firmware wiki]
=== Error: firmware xc3028-v27.fw not found ===
  firmware: requesting xc3028-v27.fw
  xc2028 1-0061: Error: firmware xc3028-v27.fw not found.

* See section [http://www.linuxtv.org/wiki/index.php/Xceive_XC3028/XC2028#How_to_Obtain_the_Firmware How to Obtain the Firmware in Xceive XC3028/XC2028 to fix it]
<br>

== Boards ==
=== How to identify my USB vendor/product id? ===

  shell> '''lsusb'''<br>
  If you can't recognize the vendor/product id from your device contact [http://www.redhat.com/mailman/listinfo/video4linux-list video4linux mail-list]

=== Validated boards ===
==== What's it? ====
  We use this term to advise that boards were tested by user or developer.

==== Table of validated boards ====
{| border="1" cellpadding="2"
!width="150"|Define
!width="200"|Name
!width="200"|Vendor/Product ID
!width="200"|Supported modes
|-
|<center>EM2820_BOARD_KWORLD_PVRTV2800RF</center> ||<center>Kworld PVR TV 2800 RF</center>
|<center>-</center> || <center>Analog</center>
|-
|<center>EM2820_BOARD_TERRATEC_CINERGY_250</center> ||<center>Terratec Cinergy 250 USB</center>
|<center>0x0ccd:0x0036</center> || <center>Analog</center>
|-
|<center>EM2820_BOARD_PINNACLE_USB_2</center> ||<center>Pinnacle PCTV USB 2</center>
|<center>0x2304:0x0208</center> || <center>Analog</center>
|-
|<center>EM2820_BOARD_HAUPPAUGE_WINTV_USB_2</center> ||<center>Hauppauge WinTV USB 2</center>
|<center>0x2040, 0x4201</center> || <center>Analog</center>
|-
|<center>EM2820_BOARD_HAUPPAUGE_WINTV_USB_2</center> ||<center>Hauppauge WinTV USB 2</center>
|<center>0x2040:0x4200</center> || <center>Analog</center>
|-
|<center>EM2880_BOARD_HAUPPAUGE_WINTV_HVR_900</center> ||<center>Hauppauge WinTV HVR 900</center>
|<center>0x2040:0x6500</center> || <center>Analog/DVB</center>
|-
|<center>EM2880_BOARD_HAUPPAUGE_WINTV_HVR_900_R2</center> ||<center>Hauppauge WinTV HVR 900 (R2)</center>
|<center>0x2040:0x6502</center> || <center>Analog/DVB</center>
|-
|<center>EM2883_BOARD_HAUPPAUGE_WINTV_HVR_950</center> ||<center>HCW HVR-980</center>
|<center>0x2040:0x6513</center> || <center>Analog/DVB</center>
|-
|<center>EM2883_BOARD_HAUPPAUGE_WINTV_HVR_950</center> ||<center>HP HVR-950</center>
|<center>0x2040:0x6517</center> || <center>Analog/DVB</center>
|-
|<center>EM2883_BOARD_HAUPPAUGE_WINTV_HVR_950</center> ||<center>HP HVR-950</center>
|<center>0x2040:0x6517</center> || <center>Analog/DVB</center>
|-
|<center>EM2883_BOARD_HAUPPAUGE_WINTV_HVR_950</center> ||<center>RP HVR-950</center>
|<center>0x2040:0x651b</center> || <center>Analog/DVB</center>
|-
|<center>EM2883_BOARD_HAUPPAUGE_WINTV_HVR_950</center> ||<center>HCW HVR-850</center>
|<center>0x2040:0x651f</center> || <center>Analog/DVB</center>
|-
|<center>EM2880_BOARD_PINNACLE_PCTV_HD_PRO</center> ||<center>Pinnacle PCTV HD Pro Stick</center>
|<center>0x2304:0x0227</center> || <center>Analog/DVB</center>
|-
|<center>EM2880_BOARD_AMD_ATI_TV_WONDER_HD_600</center> ||<center>AMD ATI TV Wonder HD 600</center>
|<center>0x0438:0xb002</center> || <center>Analog/DVB</center>
|-
|<center>EM2880_BOARD_TERRATEC_HYBRID_XS</center> ||<center>Terratec Hybrid XS</center>
|<center>0x0ccd:0x0042</center> || <center>Analog/DVB</center>
|-
|<center>EM2880_BOARD_TERRATEC_PRODIGY_XS</center> ||<center>Terratec Prodigy XS</center>
|<center>0x0ccd:0x0047</center> || <center>Analog</center>
|-
|<center>EM2820_BOARD_MSI_VOX_USB_2</center> ||<center>MSI VOX USB 2.0</center>
|<center>-</center> || <center>Analog</center>
|-
|<center>EM2800_BOARD_TERRATEC_CINERGY_200</center> ||<center>Terratec Cinergy 200 USB</center>
|<center>-</center> || <center>Analog</center>
|-
|<center>EM2800_BOARD_GRABBEEX_USB2800</center> ||<center>eMPIA Technology, Inc. GrabBeeX+ Video Encoder</center>
|<center>0xeb1a:0x2801</center> || <center>Analog</center>
|-
|<center>EM2800_BOARD_LEADTEK_WINFAST_USBII</center> ||<center>Leadtek Winfast USB II</center>
|<center>0x0413:0x6023</center> || <center>Analog</center>
|-
|<center>EM2800_BOARD_KWORLD_USB2800</center> ||<center>Kworld USB2800</center>
|<center>-</center> || <center>Analog</center>
|-
|<center>EM2820_BOARD_PINNACLE_DVC_90</center> ||<center>Pinnacle Dazzle DVC 90/DVC 100</center>
|<center>0x2304:0x0207</center> || <center>Analog</center>
|-
|<center>EM2800_BOARD_VGEAR_POCKETTV</center> ||<center>V-Gear PocketTV</center>
|<center>-</center> || <center>Analog</center>
|-
|<center>EM2820_BOARD_PROLINK_PLAYTV_USB2</center> ||<center>Pixelview Prolink PlayTV USB 2.0</center>
|<center>0xeb1a:0x2821</center> || <center>Analog</center>
|-
|<center>EM2860_BOARD_POINTNIX_INTRAORAL_CAMERA</center> ||<center>PointNix Intra-Oral Camera</center>
|<center>-</center> || <center>Analog</center>
|-
|<center>EM2820_BOARD_COMPRO_VIDEOMATE_FORYOU</center> ||<center>Compro VideoMate ForYou/Stereo</center>
|<center>0x185b:0x2041</center> || <center>Analog</center>
|-
|}<br>

=== Not Validated boards ===
==== What's it? ====
  Not validate means: that your device was added to kernel but the developer(es) doesn't have the hardware for tests.
  If you would like to help and inform that you hardware work (or not) please see section
  [http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F How to validate my vendor/product id at upstream kernel]

==== Table of NOT validated boards====
{| border="1" cellpadding="2"
!width="150"|Define
!width="200"|Name
!width="200"|Vendor/Product ID
!width="200"|Status
|-
|<center>EM2750_BOARD_DLCW_130</center> ||<center>Huaqi DLCW-130</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2820_BOARD_DLINK_USB_TV</center> ||<center>D-Link DUB-T210 TV Tuner</center>
|<center>0x2001:0xf112</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2820_BOARD_HERCULES_SMART_TV_USB2</center> ||<center>Hercules Smart TV USB 2.0</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2820_BOARD_PINNACLE_USB_2_FM1216ME</center> ||<center>Pinnacle PCTV USB 2 (Philips FM1216ME)</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2820_BOARD_GADMEI_UTV310</center> ||<center>Gadmei UTV310</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2820_BOARD_LEADTEK_WINFAST_USBII_DELUXE</center> ||<center>Leadtek Winfast USB II Deluxe</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2820_BOARD_PINNACLE_DVC_100</center> ||<center>Pinnacle Dazzle DVC 100</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2820_BOARD_VIDEOLOGY_20K14XUSB</center> ||<center>Videology 20K14XUSB USB2.0</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2821_BOARD_PROLINK_PLAYTV_USB2</center> ||<center>SIIG AVTuner-PVR/Prolink PlayTV USB 2.0</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2821_BOARD_SUPERCOMP_USB_2</center> ||<center>Supercomp USB 2.0 TV</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2821_BOARD_USBGEAR_VD204</center> ||<center>Usbgear VD204v9</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2860_BOARD_NETGMBH_CAM</center> ||<center>NetGMBH Cam</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2860_BOARD_TYPHOON_DVD_MAKER</center> ||<center>Typhoon DVD Maker</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2860_BOARD_GADMEI_UTV330</center> ||<center>Gadmei UTV330</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2860_BOARD_TERRATEC_HYBRID_XS</center> ||<center>Terratec Cinergy A Hybrid XS</center>
|<center>0x0ccd, 0x004f</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2861_BOARD_KWORLD_PVRTV_300U</center> ||<center>KWorld PVRTV 300U</center>
|<center>0xeb1a, 0xe300</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2861_BOARD_YAKUMO_MOVIE_MIXER</center> ||<center>Yakumo MovieMixer</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2861_BOARD_PLEXTOR_PX_TV100U</center> ||<center>Plextor ConvertX PX-TV100U</center>
|<center>0x093b:0xa005</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2870_BOARD_TERRATEC_XS</center> ||<center>Terratec Cinergy T XS</center>
|<center>0x0ccd:0x0043</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2870_BOARD_TERRATEC_XS_MT2060</center> ||<center>Terratec Cinergy T XS (MT2060)</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2870_BOARD_KWORLD_350U</center> ||<center>Kworld 350 U DVB-T</center>
|<center>0xeb1a:0xe350</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2870_BOARD_KWORLD_355U</center> ||<center>Kworld 355 U DVB-T</center>
|<center>0xeb1a:0xe355</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2870_BOARD_PINNACLE_PCTV_DVB</center> ||<center>Pinnacle PCTV DVB-T</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2870_BOARD_COMPRO_VIDEOMATE</center> ||<center>Compro, VideoMate U3</center>
|<center>0x185b:0x2870</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2880_BOARD_TERRATEC_HYBRID_XS_FR</center> ||<center>Terratec Hybrid XS Secam</center>
|<center>0x0ccd:0x004c</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2880_BOARD_MSI_DIGIVOX_AD</center> ||<center>MSI DigiVox A/D</center>
|<center>0xeb1a:0xe310</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2880_BOARD_MSI_DIGIVOX_AD_II</center> ||<center>MSI DigiVox A/D II</center>
|<center>0xeb1a:0xe320</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2880_BOARD_KWORLD_DVB_305U</center> ||<center>KWorld DVB-T 305U</center>
|<center>0xeb1a:0xe305</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2880_BOARD_KWORLD_DVB_310U</center> ||<center>KWorld DVB-T 310U</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2881_BOARD_DNT_DA2_HYBRID</center> ||<center>DNT DA2 Hybrid</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2881_BOARD_PINNACLE_HYBRID_PRO</center> ||<center>Pinnacle Hybrid Pro</center>
|<center>-</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2882_BOARD_PINNACLE_HYBRID_PRO</center> ||<center>Pinnacle Hybrid Pro (2)</center>
|<center>0x2304:0x0226</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2882_BOARD_KWORLD_VS_DVBT</center> ||<center>Kworld VS-DVB-T 323UR</center>
|<center>0xeb1a:0xe323</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2882_BOARD_TERRATEC_HYBRID_XS</center> ||<center>Terratec Hybrid XS (em2882)</center>
|<center>0x0ccd:0x005e</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|<center>EM2883_BOARD_KWORLD_HYBRID_A316</center> ||<center>Kworld PlusTV HD Hybrid 330</center>
|<center>0xeb1a:0xa316</center> || <center>Not validated ([http://www.linuxtv.org/v4lwiki/index.php/Em28xx_devices#How_to_validate_my_vendor.2Fproduct_id_at_upstream_kernel.3F change it])</center>
|-
|}

==== How to validate my vendor/product id at upstream kernel?====
  
* Send your board name, lsusb output and tests made to [http://www.redhat.com/mailman/listinfo/video4linux-list video4linux mail-list]<br>

* Example:

  From: foobar
  '''To''': video4linux-list
  '''Subject''': em28xx: new board id [0b1a:2821]<br>
  Hi, <br>
  I've made tests with my '''Pixelview''' board:<br>
  '''Model''': Prolink PlayTV USB 2.0
  '''Vendor/Product id''': [0b1a:2821].<br>
  '''Tests made''': <br>
      - Analog [Worked]
      - DVB    [this board doesn't support dvb mode]<br>
  '''Tested-by''': foobar <foobar@foobar.com><br>
  ~foobar<br>
Otherwise, if you had any issue, please contact [http://www.redhat.com/mailman/listinfo/video4linux-list video4linux mail-list].

== If some features doesn't work (i.e: audio, dvb, s-video)==
===Should I call whom?===
  Please contact [http://www.redhat.com/mailman/listinfo/video4linux-list video4linux mail-list].
===Usbsnoop===
  If you were asked to sniff your device, use this [http://www.linuxtv.org/v4lwiki/index.php/Usbsnoop instructions]

==About em28xx models==
===em2800/em2820/em2821/em2840===
* used on older analog only device designs. These chips have support for USB Audio Class; so, audio module is snd-usb-audio

===em2820/em2840 based devices===
* [[Em2820/gadmei utv 310]]
** [[Em2820:Talk]]
* [[Pinnacle_PCTV_USB2]]
* [[Em2820/pinnacle]]
* [[V-Gear PocketTV]]
* [[USBGear USB2.0 Video Adapter With Audio (VD204)]]

===em2880/2881/2883===
* supports DVB/ATSC. Doesn't provide USB Audio Class. Instead, digital audio is provided via an USB Vendor Class; so, these chips require the em28xx-alsa module for digital audio to work.

===em2880 based devices===
* KWorld 350U DVB-T 
* [[KWorld DVB-T 355U]]
* KWorld 310U  
* KWorld USB2800
* [[Em2880/PinnaclePCTV]]
* [http://videologyinc.com/cameras/ccd-board-camera-20K14XUSB.htm Videology 20K14XUSB webcam]

===em2750===
* Seem to be used by some [[Webcams]].

==Some Misc stuff==
The following needs to be cleaned up and/or integrated into the article:
* [[Em2880/Eeproms]] 
* [[Em2880/Todo]]
* [[Em2880/remote]]

==Feature Support==
* No firmware is required for em28xx ICs ... note: though em28xx based devices paired with some tuners will need firmware for the tuner (i.e. there are em28xx based devices paired with a [http://www.linuxtv.org/wiki/index.php/Xceive_XC3028/XC2028 XCeive XC3028 or XC2028] tuner, which require a generic firmware from Xceive).

==About Driver==
* Development -- originally by 4 Ludovico Cavedon, Markus Rechberger, Mauro Carvalho Chehab, Sascha Sommer.<br>
* One of the authors, Markus Rechberger, forked the upstream project.

==External Links==
* [http://www.supreme-hk.com/soft/EM2880_datasheet.pdf EMPIA EM2880 datasheet]
* [http://www.supreme-hk.com/soft/EM2870_datasheet.pdf EMPIA EM2870 datasheet]
* [http://www.empiatech.com.tw/pro_em2880.htm EMPIA EM2880 product page]
* [http://www.empiatech.com.tw/pro_em2820.htm EMPIA EM2820/EM2840 product page]
* [http://www.empiatech.com.tw/pro_em2750.htm EMPIA EM2750 product page]
* [http://mcentral.de/wiki/index.php5/Main_Page mcentral.de wiki] offers alternative, out of kernel, drivers for some em28xx based devices: 
** [http://mcentral.de/wiki/index.php5/Em2880 mrec's page on the em2880] ... note: that the information seems heavily tied to devices which utilise a xceive xc3028 tuner ... hence you may also want to read his xc3028 page for related info
** [http://mcentral.de/wiki/index.php5/Em2820 mrec's page on the em2820]

== Additional Help ==
Contact video4linux developers at [http://www.redhat.com/mailman/listinfo/video4linux-list vide4linux-maillist]