All,

I have gotten my HDLC driver up to the point where it can register itself
with the Linux kernel. However now I am faced with a dilemma and style
question, that is probably best answered by you driver developers that have
more experience.

I am putting support for multiple PHY's into the HDLC driver, but after
converting it to use the of_device tree, and inserting a UCC@5000 for a
single UCC HDLC driver, it occurred to me that if I insert more devices
(UCC@6000, UCC@7000, UCC@8000) that the driver will attempt to load multiple
times.

So here is the question.

Solution 1:
Should I develop the system to have a single ucc@xxxx entry in the
platform.dts file and have a field(s) like phy-count=<4>, to support
multiple devices? And have each instance of the module contain private data
for one UCC, interrupt handling, etc...  

OR

Solution 2:
Is there a way to have a module know if it has already been loaded, so it
doesn't insert multiple times and then play the rest like Solution 3?

OR

Solution 3:
Have phy-count=4; defined in the driver header, or a module parameter, and
have a single module instance of the driver itself responsible for creating
a single private data structure and setting up multiple UCC's and PHY's?

This also feeds into a question on SET_NETDEV_DEV. How does it react to
multiple net devices attached to a single base driver?

-Russ

-----Original Message-----
From: Andy Fleming [mailto:afleming@freescale.com]
Sent: Tuesday, January 29, 2008 2:33 PM
To: rmcguire@videopresence.com
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: SET_NETDEV_DEV -> 83xx HDLC Driver??


On Jan 25, 2008, at 20:43, Russell McGuire wrote:

quoted

All,

I am partly done porting a combination of the 83xx ATM driver and
dscc4 HDLC
driver into a 83xx HDLC driver.

However, encounter a call I don't truly understand.

SET_NETDEV_DEV(dev, pointer_to_some_handle);

I can see plenty of examples of this registering some kind of PCI
device
handle, however in this case I am not using a PCI device. So what
should the
pointer be? Or can this call be ignored, and if so what are the
consequences?

I see the some of the Freescale Ethernet devices don't use this call.

Anyway, can somebody shed some light on if I am going to need this,
or a way
to get it to work, without creating a PCI device?

Look at gianfar.c (which uses a platform_device) or ucc_geth (which
uses an of_device).  Which freescale devices don't use that call?
We'll fix them.

Andy