staging: bcm2835-camera: Replace spinlock protecting context_map with mutex
The commit "staging: bcm2835-camera: Replace open-coded idr with a struct idr."
replaced an internal implementation of an idr with the standard functions
and a spinlock. idr_alloc(GFP_KERNEL) can sleep whilst calling kmem_cache_alloc
to allocate the new node, but this is not valid whilst in an atomic context
due to the spinlock.
There is no need for this to be a spinlock as a standard mutex is
sufficient.
Fixes: 950fd867c635 ("staging: bcm2835-camera: Replace open-coded idr with a struct idr.") Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org> Signed-off-by: Stefan Wahren <wahrenst@gmx.net> Acked-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Acked-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>