Subject: Re: CPM2 USB host driver

From: Anton Vorontsov <[email-masked]>
Date: Fri, 30 Nov 2007 19:11:36 +0300

On Fri, Nov 30, 2007 at 04:28:27PM +0100, Laurent Pinchart wrote:
[...]
> > I tried to forward-port FHCI from Freescale 2.6.11 kernels. Twice.
> > But these efforts always stumbled over more important tasks.
> 
> Do you think I start from the FHCI driver provided by Freescale for 2.6.11, 
> from the cpm2usb driver or from scratch ?

Well, the same question I asked myself when I was looking at
FHCI driver back then. USB subsystem changed drastically, powerpc
bits changed too. Forward porting or doing from scratch.. hm.

Unfortunately I didn't look into cpm2usb, thus I can't tell
whether it will be easier to reuse.

As for FHCI driver, it's not that big (6100 lines host patch + 3516
lines usbgadget patch), but since usb subsystem changed: you have to
know all the changes (or to look them up) and blindly follow them. Or
start from scratch with FHCI/cpm2usb as the reference, thus evolve
into Linux USB expert one day.

I've tried first option -- it's boring to death (that is, you're
doing job USB maintainers done years ago for in-tree drivers ;-).

Today, I think I would choose the second option. Definitely more
fun, and most probably quicker to progress. Though, I repeat,
I didn't look into cpm2usb project.

-- 
Anton Vorontsov
email: [email-masked]
backup email: [email-masked]
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