Video4linux

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Video4Linux is not compiled by default in the Gumstix buildroot. These instructions detail how to add it.

Contents

Instructions for Setting Up

These instructions explain how to set up video4linux as well as a webcam through the USB port. Thanks to Jnaneshwar Das, who posted the original version of these instructions here.

Video4Linux

I used the Philips webcam driver for linux (pwc) and video4Linux. . The gumstix kernel source already has source for pwc. But the device driver has to be included in the kernel build. To do this I did the following:

After building the buildroot, go to "gumstix-buildroot/build_arm_nofpu/linux-2.6.21gum" folder, and 'make menuconfig'.

There are a few module dependencies for the pwc module to be enabled. Follow these steps

1) enable "Bus options (PCI, PCMCIA, EISA, MCA, ISA)  ---> PCI Support"       (this will enable the USB host module options)
2) enable "Device Drivers  ---> Multimedia devices  ---> Video For Linux"
3) enable "Device Drivers  ---> Multimedia devices --->  Video For Linux ---> Video For Linux API  ---> Video Capture Adapters  --->  V4L USB devices ---> USB Philips Cameras    (or driver of your choice of camera if it is listed)
4) save configuration file and exit. Go back to the 'gumstix-buildroot' folder and 'make'

Some posts by Dave Hylands and Dave Touretzky on the gumstix users mailing list said that the architecture must be specified, and suggested this configuration, which is very similar to the one above it:

make ARCH=arm menuconfig
--> Device drivers --> USB Support --> Support for host-side USB
--> Device drivers --> USB Support --> turn off USB Gadget support
--> Multimedia devices --> Video For Linux
--> Multimedia devices --> Video Capture Adapters --> V4L USB Devices --> GSPCA (Generic Software Package for Camera Adaptors) 

After 'make' completes, you will find the .ko files in, '/gumstix-buildroot/build_arm_nofpu/linux- 2.6.21gum/drivers/media/video/pwc/' folder. You need to copy the pwc folder with all the .ko files to "/lib/modules/2.6.21gum/kernel/drivers/media/video/pwc".

On the gumstix,

gumstix # 'depmod -a'
gumstix # modprobe pwc

Now when you plug in the webcam and type 'dmesg', you should see something similar to the following.

hda: max request size: 128KiB
hda: 2002896 sectors (1025 MB) w/1KiB Cache, CHS=1987/16/63
hda: hda1
eth0: no IPv6 routers present
Linux video capture interface: v2.00
pwc: Philips webcam module version 10.0.12 loaded.
pwc: Supports Philips PCA645/646, PCVC675/680/690, PCVC720[40]/730/740/750 & PCVC830/840.
pwc: Also supports the Askey VC010, various Logitech Quickcams, Samsung MPC-C10 and MPC-C30,
pwc: the Creative WebCam 5 & Pro Ex, SOTEC Afina Eye and Visionite VCS-UC300 and VCS-UM100.
pwc: Trace options: 0x0001
usbcore: registered new interface driver Philips webcam

Hardware

Verdex

Logitech Quickcam Pro 4000 webcam

Related Links

"V4L Drivers"

"V4L Wiki"

Quick Capture Interface

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