How to pass a custom config file name through "postcss.config.js"

[GHNewbiee]

In postcss.config.js when plugins is an Array we write:

  ...
  plugins: [
    require('tailwindcss')('.../tailwindcss.config.path.and.name.js'),
  ]
  ...

But, what's the name of the property that is used when plugins is an Object?

  ...
  plugins: {
    'tailwindcss': { property: '.../tailwindcss.config.path.and.name.js' },
  }
  ...

or the following is enough?

  ...
  plugins: {
    'tailwindcss': '.../tailwindcss.config.path.and.name.js',
  }
  ...

Of course, I do suppose that tailwindcss.config.js can lie inside any subdirectory of the project root directory and not necessarily in the root directory. Tia