faq

这是一个Linux下的USB摄像头捕捉程序

Zoran/Nogatech FAQ 
------------------

Due to popluar demand.  Here is the FAQ about some of the issues with the installation and usage of the USBVision device driver.

1) I'm getting this error message with gcc when compiling the driver.
 usbvision.c:859: error: redefinition of `video_get_drvdata'
 /usr/src/linux-2.4.26/include/linux/videodev.h:71: error: `video_get_drvdata' previously defined here
 usbvision.c:864: error: redefinition of `video_set_drvdata'
 /usr/src/linux-2.4.26/include/linux/videodev.h:76: error: `video_set_drvdata' previously defined here
 
Answer: This problem is a result that the kernel which is installed on your computer has these two structures already defined.
 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,4,27)
 
 Edit the KERNEL_VERSION to the right version number of your kernel installed.Also, notify one of the authors on sourceforge.net about the 
 Problem. They will update the CVS version of the driver.

 
 
2) I'm getting this error message with gcc when compiling the driver.
 compat.h" not found error in saa7111-new.c.
 
Answer: Just create a symlink in the local directory to /usr/src/linux/drivers/media/video/i2c-compat.h and it will compile.

 
 
3) I'm getting this error message with gcc when compiling the driver.
 usbvision.c:2959: error: unknown field `owner' specified in initializer
 usbvision.c:2959: warning: missing braces around initializer
 usbvision.c:2959: warning: (near initialization for `i2c_adap_template.name')
 usbvision.c:2959: warning: initialization makes integer from pointer without a cast
 usbvision.c:2959: error: initializer element is not computable at load time
 usbvision.c:2959: error: (near initialization for `i2c_adap_template.name[0]')
 usbvision.c:2961: error: initializer element is not constant
 usbvision.c:2961: error: (near initialization for `i2c_adap_template.name')
 
Answer: The .owner field is define in newer versions of i2c.  Since most distributions do not have this newer version, the .owner field has to be checked with an if statement..
 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,4,27)
 .owner             = THIS_MODULE,
 Edit the KERNEL_VERSION to the right version number of your kernel installed.  Also, notify one of the authors on sourceforge.net about the problem.   
 They will update the CVS version of the driver.


If you have any other questions, please check out the forums at http://sourceforge.net/forum/?group_id=27255