Re: [PATCH V6] misc: pci_endpoint_test: simplify endpoint test read and write operations

[Bjorn Helgaas]

On Mon, Feb 07, 2022 at 11:20:15PM -0500, Li Chen wrote:
>  ---- On Mon, 07 Feb 2022 12:56:13 -0500 Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote ----
>  > On Mon, Feb 07, 2022 at 04:09:05AM -0500, Li Chen wrote:
>  > > #define to_endpoint_test(priv) container_of((priv), struct pci_endpoint_test, \
>  > > -                     miscdev)
>  > > +                        miscdev)
>  > 
>  > Always indent with tabs when possible:
>  > 
>  >   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/coding-style.rst?id=v5.16#n18
>  > 
>  > Hmm, coding-style.rst is unfortunately not very explicit about that.
>  > 
>  > But it's obvious from the existing code in this file that things
>  > should not be indented four spaces, as you did in
>  > pci_endpoint_test_transfer_data().
> 
> So, can I say space is not allowed in indentation? If so, I should
> not use emacs's tabify, because it will not convert 4 space to
> 8-width tab. I'm also not sure is scripts/Lindent or clang-format is
> a good choice here, they do too much changes.

I don't know how emacs, Lindent, clang-format, etc work.  I *can* tell
you that in Linux code:

  - indents always use tabs (width 8) when possible,

  - up to 7 spaces are allowed after a tab when needed to align
    something with the previous line, and

  - a tab never directly follows a space.

Bjorn