Documentation describes semantics, limitations and a typical use case
scenario.
Signed-off-by: Adrian Larumbe <adrianml@alumnos.upm.es>
Link: https://lore.kernel.org/r/20211101180825.241048-2-adrianml@alumnos.upm.esSigned-off-by: Vinod Koul <vkoul@kernel.org>