According to the V4L2 API, the prot argument of the mmap() system call must be set to PROT_READ | PROT_WRITE by the caller (whetever is the direction of data exchange):
http://www.linuxtv.org/downloads/video4linux/API/V4L2_API/spec-single/v4l2.html#FUNC-MMAP The UVC driver should enforce this requirement by checking the memory flags and returning the -EACCESS error code to the caller, in case of missing flags. --- On the other hand, "luvcview" does not pass PROT_WRITE to mmap(), which is a bug too, since it may cause other more compliant V4L2 drivers to return an error if PROT_WRITE is not set. Best regards Luca Risolia _______________________________________________ Linux-uvc-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
