can i pass min and max to datetime_select ?
Why have you asked the same question twice?
You can use validations to ensure that only valid values are saved,
but datetime_select is not able to limit the range.
I believe that in order to do that you would need a js solution such as
http://amsul.ca/pickadate.js/date/, though I have not used it.
Are you actually trying to input an elapsed time or is it an actual
datetime that you want?
it’s for scheduling, you should only be able to schedule from present to future but not have backdate options