SHT4X_CMD_LEN
ret = i2c_master_send(client, cmd, SHT4X_CMD_LEN);
ret = i2c_master_send(data->client, &cmd, SHT4X_CMD_LEN);
ret = i2c_master_send(client, cmd, SHT4X_CMD_LEN);
if (ret != SHT4X_CMD_LEN)
u8 cmd[SHT4X_CMD_LEN] = {SHT4X_CMD_MEASURE_HPM};