T_RISEFALL
nvkm_i2c_delay(bus, T_RISEFALL);
nvkm_i2c_delay(bus, T_RISEFALL);
u32 timeout = T_TIMEOUT / T_RISEFALL;
nvkm_i2c_delay(bus, T_RISEFALL);
nvkm_i2c_delay(bus, T_RISEFALL);