nvkm_i2c_pad_acquire
ret = nvkm_i2c_pad_acquire(pad, NVKM_I2C_PAD_AUX);
ret = nvkm_i2c_pad_acquire(pad, NVKM_I2C_PAD_I2C);
int nvkm_i2c_pad_acquire(struct nvkm_i2c_pad *, enum nvkm_i2c_pad_mode);