Not detecting raspberry pi camera

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I am doing a project in which I have to use a usb camera and the raspberry pi camera. Therefore, I installed first the usb_cam package and tried to make a web streaming with the rasbperry pi camera. However, the raspberry cam was not detected as a /dev/video device so I execute the following commands to detect the pi camera as a /dev/video device: sudo rpi-update and sudo modprobe bcm2835-v4l2. Once it was detected as a /dev/video device, I used the usb_cam and web_server package to make the stream, everything worked perfectly until I installed the raspicam_node. Now it is impossible to detect /dev/video0. I would be really grateful if someone would help me.