epa-pinentry-mode

epa-pinentry-mode is a variable defined in `epa.el'.
Its value is

nil

Documentation:
The pinentry mode.

GnuPG 2.1 or later has an option to control the behavior of
Pinentry invocation. Possible modes are: `ask', `cancel',
`error', and `loopback'. See the GnuPG manual for the meanings.

In epa commands, a particularly useful mode is `loopback', which
redirects all Pinentry queries to the caller, so Emacs can query
passphrase through the minibuffer, instead of external Pinentry
program.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 25.1 of Emacs.