I assume the magic can heal the damage from suffocation and return the mind to a functional post-suffocated state, but it will be more torture than just blacking out.
Also, an irrelevant fun fact. It takes longer to drown in salt water than fresh water because swallowing fresh water can be directly absorbed inside the body and enters directly into the blood circulation. This osmosis quickly increases blood volume, but doing so dilutes the amount of red blood cells trying to keep the muscles active. SO, the drowning person's lungs are not only getting no oxygen intake, but also any reserve oxygen that already was in the bloodstream is now failing to reach the muscles like they're supposed to. (Therefore, even if all your air gets knocked out, drinking in the water is even worse than just not breathing.)
Alternatively, salt water does not trigger osmosis, so in those cases you're just not breathing anyways.