Re: [PATCH v9 1/5] firmware: add extensible driver data params

From: Li, Yi
Date: Tue Jun 20 2017 - 11:20:57 EST

On 6/19/2017 8:48 PM, AKASHI Takahiro wrote:
On Mon, Jun 19, 2017 at 05:51:08PM -0500, Li, Yi wrote:
Hi Greg,

On 6/17/2017 2:38 PM, Greg KH wrote:
On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:
On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:

What you have to ask yourself really is if this makes it *less complex* and
helps *clean things up* in a much better way than it was before. Also does it
allow us to *pave the way for new functionality easily*, without creating
further mess?

I agree, that's what I'm saying here. I just do not see that happening
with your patch set at all. It's adding more code, a more complex way
to interact with the subsystem, and not making driver writer lives any
easier at all that I can see.

Again, the code is now bigger, does more, with not even any real benefit
for existing users.

I am still new to the upstreaming world, pardon me if my understanding is
naive. :) My take with Luis's driver data API is that it adds a wrapper on
top of the old request_firmware APIs, so the new features can be
added/disabled by the parameters structures instead of adding/changing API
functions. Agree that there is not much new for existing users. It adds more
codes (not necessary more complex) but create a consistent way for extension

Most of code of my feature, firmware signing, is implemented in common
place between old and new APIs, while only new API has a parameter,
DRIVER_DATA_REQ_NO_SIG_CHECK, which allow users to enable/disable
this feature per-driver-datum. Simple enough.

I meant to say more code does NOT necessary equal to more complex, sorry for the confusion.

So what matters is adding yet another variant of request_firmware_xx()
vs. adding a mere parameter?

Agree, I also prefer the parameter approach.

-Takahiro AKASHI

Below are 3 examples I tried to add streaming support to load large firmware
Adding streaming with driver data API: . This patch series depends on
non-cache patch series , which is
bigger than it should be since it added some codes to test firmware caching.
and pre-allocate buffer patch series

By comparison, here is my old streaming RFC with original firmware class:
Do you think this is the better way?