Wow... old code.

The SDDR-09 driver is, well, not one of our finest works.  :)

We call usb_set_configuration() to change to a specific alternate
configuration for this device.  Is there some sort of problem with calling
that function?

Matt

On Mon, May 13, 2002 at 01:40:59PM -0400, Johannes Erdfelt wrote:
> On Mon, May 13, 2002, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
> > > Are you using an invalid endpoint? You're right, MxPS is not zero in
> > > any of those, but since it parsed alright, there's no reason why
> > > dev->exmaxpacketin/out should be 0.
> > 
> > It is not clear at all why dev->epmaxpacketin/out should be
> > anything but 0. This array is never initialized as far as
> > I can see.
> > 
> > More precisely, the value for endpoint 0 is set in
> > usb_new_device(). Values for other endpoints only in
> > usb_set_maxpacket() [which has the comment "hub-only!!"].
> > 
> > And usb_set_maxpacket() is called only by hub.c:usb_reset_device()
> > and core/usb.c:usb_set_interface() and usb_set_configuration().
> > 
> > From the comments it looks like usb_set_interface() and
> > usb_set_configuration() are called only in non-default situations.
> > In any case, usb_set_interface() is not called in usb-storage,
> > and usb_set_configuration() only in some very ugly, kludgy
> > #ifdef CONFIG_USB_STORAGE_SDDR09 - part of storage/usb.c.
> > 
> > So, at least in usb-storage, it seems that epmaxpacket*
> > will be valid only by accident.
> > 
> > It also looks like storage/usb.c picks an essentially random
> > endpoint to use, ignoring all others.
> > 
> > Let me cc Matt so that he can comment.
> 
> usb_new_device -> usb_set_configuration -> usb_set_maxpacket.
> 
> So it will be set atleast once.
> 
> I wonder if usb-storage is using a different configuration without
> calling usb_set_configuration?
> 
> JE

-- 
Matthew Dharm                              Home: [EMAIL PROTECTED] 
Maintainer, Linux USB Mass Storage Driver

What, are you one of those Microsoft-bashing Linux freaks?
                                        -- Customer to Greg
User Friendly, 2/10/1999

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