You would have to compile the desired camera drivers as a module for the mipsel kernel, in some way. I think this needs some more intensive tweaking of the configure scripts of the drivers or there integration into the kernel source tree of the development system. i tryed to do this with the Drivers for some ultra-lowcost sunplus chipsets, but endet up seeing the driver supported the cam only very ugly (incorrect shutter controll). You may check first on a normal linux box that the driver works well with the cam...
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