Re: [RFC PATCH v2 3/6] tpm: add send_recv() ops in tpm_class_ops

From: Jarkko Sakkinen
Date: Thu Mar 06 2025 - 16:53:05 EST


On Wed, Mar 05, 2025 at 03:02:29PM -0400, Jason Gunthorpe wrote:
> On Wed, Mar 05, 2025 at 10:04:25AM +0100, Stefano Garzarella wrote:
> > Jason suggested the send_recv() ops [2], which I liked, but if you prefer to
> > avoid that, I can restore what we did in v1 and replace the
> > TPM_CHIP_FLAG_IRQ hack with your point 2 (or use TPM_CHIP_FLAG_IRQ if you
> > think it is fine).
>
> I think it is a pretty notable simplification for the driver as it
> does not need to implement send, status, req_canceled and more ops.
>
> Given the small LOC on the core side I'd call that simplification a
> win..

I'm sorry to disagree with you on this but adding a callback for
one leaf driver is not what I would call "a win" :-)

I mean, it's either a minor twist in

1. "the framework code" which affects in a way all other leaf drivers.
At bare minimum it adds a tiny bit of complexity to the callback
interface and a tiny bit of accumulated maintenance cost.
2. in the leaf driver

So I'd really would want to keep that tiny bit of extra complexity
localized.

>
> Jason

BR, Jarkko