I have Picamera v2 which I have been using Rpi3 for a while now and it has been working properly.
vcgencmd get_camera I get
supported = 1, detected = 1
But while i run raspistill -o cam.jpg. I get:
mmal: mmal_vc_component_enable: failed to enable component: ENOSPC
mmal: camera component couldn't be enabled
mmal: main: Failed to create camera component
mmal: Failed to run camera app. Please check for firmware updates
I had: update my firmware, check if it have any app use my camera, recable camera, enable my camera, set my gpu-mem to 256, edit cmdline.txt like this post, check if there are any motion app.
Is the problem is a hardware problem with the camera and i have to change the camera for a new one ? It work finely yesterday.