nvkm_clk_ustate
int nvkm_clk_ustate(struct nvkm_clk *, int req, int pwr);
ret |= nvkm_clk_ustate(clk, args->v0.ustate, args->v0.pwrsrc);
ret |= nvkm_clk_ustate(clk, args->v0.ustate, 0);
ret |= nvkm_clk_ustate(clk, args->v0.ustate, 1);
ret = nvkm_clk_ustate(base, pstates[i].pstate, 0);
ret |= nvkm_clk_ustate(base, pstates[i].pstate, 1);