6.4. The cx88 driver — The Linux Kernel 5.18.5-gnu-1 documentation

# 6.4. The cx88 driver

Author: Gerd Hoffmann

This is a v4l2 device driver for the cx2388x chip.

## 6.4.1. Current status

video

  - Works.

  - Overlay isn’t supported.

audio

  - Works. The TV standard detection is made by the driver, as the hardware has bugs to auto-detect.

  - audio data dma (i.e. recording without loopback cable to the sound card) is supported via cx88-alsa.

vbi

  - Works.

## 6.4.2. How to add support for new cards

The driver needs some config info for the TV cards. This stuff is in cx88-cards.c. If the driver doesn’t work well you likely need a new entry for your card in that file. Check the kernel log (using dmesg) to see whenever the driver knows your card or not. There is a line like this one:

    cx8800[0]: subsystem: 0070:3400, board: Hauppauge WinTV \
            34xxx models [card=1,autodetected]

If your card is listed as “board: UNKNOWN/GENERIC” it is unknown to the driver. What to do then?

1. Try upgrading to the latest snapshot, maybe it has been added meanwhile.

2. You can try to create a new entry yourself, have a look at cx88-cards.c. If that worked, mail me your changes as unified diff (“diff -u”).

3. Or you can mail me the config information. We need at least the following information to add the card:

   > - the PCI Subsystem ID (“0070:3400” from the line above, “lspci -v” output is fine too).

   > - the tuner type used by the card. You can try to find one by trial-and-error using the tuner=<n> insmod option. If you know which one the card has you can also have a look at the list in CARDLIST.tuner