[U-Boot-Users] Contribution: EHCI USB HC driver

[Markus Klotzbücher]

Hi Marcel, Detlev,

I somehow missed this mail, thanks for following up!

Detlev Zundel <dzu at denx.de> writes:

>> Juniper Networks wrote a driver for the EHCI UCB HC and I'd like to
>> contribute that back if there's interest. Besides a new piece of code,
>> this also changes some of the common USB code so that high-speed
>> devices and split-transactions are supported.
>
> Cool!

Very nice indeed, thanks for sharing Marcel!

>> At this time the EHCI driver is exclusive in that there's no support
>> for having the companion controller active. I presume this is one of
>> the major themes for adding EHCI support, so that's definitely open
>>  for discussion.

This is definitely an issue, but not one that can or should be solved
for the USB subsystem solely. What we really need to implement such
features in a clean manner is a well thought out U-Boot Driver Model...

>> Attached a patch with the common code changes as well as the EHCI
>> driver itself. The patch does not contain any changes to get it built
>> (i.e. included in libusb, etc). A seasoned U-Boot developer should
>> have no problem playing with it, while the details are being worked
>> out for getting this alongside a USB 1.1 HC driver.

Nice work! One thing we definitely will want to do is separate the
low-level board/cpu specific and generic ehci code such as done for the
generic ohci driver. From a first look it doesn't seem this would be too
hard.

> I think this will have to go through Markus' USB tree, so I put him on
> CC. Markus, could you perhaps add a branch in your repository to give
> this (and the upcoming) patches a better visibility even during
> development?

Yes, I'll do that.

> I am actually pretty happy, that finally someone is actively starting to
> put effort into moving the usb support in U-Boot forward - and before
> this gets interpreted wrongly - in my opinion Markus does a great job as
> a USB maintainer and I definitely do not want lessen his work here, but
> as we talked about a few times, most of his effort got sucked up in
> maintaining the current code base.

;-) No offence taken! I'm also glad to see some effort in this
direction!

Best regards

Markus Klotzbücher

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