  We study spin-photon coupling in cavity in the presence of relative phase
shift between two ferromagnetic resonance driving forces. We show that the
anticrossing gap can be manipulated by varying the relative phase. Increasing
the phase difference leads to narrowing the anticrossing gap of hybridized
modes and eventually to phase locked coupling at the value of relative phase of
{\pi}: The FMR and cavity modes become phase locked and oscillate at the same
frequency near the resonance frequency. Characteristic linewidth drop and
transmission amplitude enhancement are demonstrated. The phase resolved
spin-photon coupling can be used both for phase imaging and controlling
coupling parameters.
