Re: config questions - the hub

Re: config questions - the hub

[Ajay]

> Why do you want to talk to the root uhci hub?  Why
> would you want to
> talk to _any_ hub for that matter?  You can't really
> do anything with
> them.
I am trying to make a utility that is VID-PID
independent, checks if a device is a storage device,
issues SCSI commands to check the number of LUNS,
issues SCSI commands to check media presence, and
mounts the media.  This is because I had trouble with
a SCM Orca reader -  I had to enter a vid - pid match
in usb.usermap and a corresponding driver in
/etc/hotplug/usb, but I dont want to do that for every
storage device. This is simply because my system _has_
the necessary driver (usb-storage) that works for most
storage devices. I wasnted to go the extra step and
automate everything - mount the media and put the icon
on the desktop and anything else necessary without the
(naive) user having to do anything, provided the
device is a storage device. 

I'm not sure if this can be achieved in hotplug
straightaway - AFAICS we have to enter the VID-PID (if
the system doesn't have it already.)

So my thought process was this:
1. Communicate with the hub and check the devices
plugged in at present.
2. Check if any of them are storage devices (is this
possible using ioctls?)
3. Check if a corresponding SCSI enumeration is found
in /proc/scsi/usb-strorage-#.
4. Then issue SCSI commands and verify stuff - LUNs,
Media presence, etc.
5. Mount, put icon , do whatever necessary.

I wanted to communicate with the hub simply because I
thought it would be faster than opening
/proc/bus/usb/devices everytime and reading each line.
I'm not sure if I'm right in this regard though.

I would appreciate any insight into this. 

> 
> And device 180 0 is for a USB printer, not a USB
> hub.  See the list at:
> 	http://www.linux-usb.org/usb.devices.txt
> for more info on the reserved USB major:minor
> numbers.

But /proc/devices lists 180 usb and 180 is the major
device number. I did not have any other usb device
plugged in at the time, so I reasoned it must have
been the hub. Guess I was wrong :(.

Thanks and regards
- Ajay

==/*------------------------------*\
 *----A Ajay Srinivasan ----* 
 * a_ajay_sr@yahoo.com * 
\*------------------------------*/

__________________________________________________
Do You Yahoo!?
Everything you'll ever need on one web page
from News and Sport to Email and Music Charts
http://uk.my.yahoo.com


-------------------------------------------------------
This sf.net email is sponsored by: Jabber - The world's fastest growing 
real-time communications platform! Don't just IM. Build it in! 
http://www.jabber.com/osdn/xim
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel

Re: config questions - the hub

[Greg KH]

On Wed, Aug 28, 2002 at 02:59:47PM +0100, Ajay wrote:
> 
> So my thought process was this:
> 1. Communicate with the hub and check the devices
> plugged in at present.

No, you can not talk to a USB hub directly.  Look for the devices
themselves, if they are present, you can talk to them.

> 2. Check if any of them are storage devices (is this
> possible using ioctls?)

Look at the info in /proc/bus/usb/devices (the descriptor).  That will
tell you if they are storage devices.  You can also read the USB
descriptor through usbfs by doing a simple read().

> But /proc/devices lists 180 usb and 180 is the major
> device number. I did not have any other usb device
> plugged in at the time, so I reasoned it must have
> been the hub. Guess I was wrong :(.

Heh, the USB core registers that number, and then doles out the minor
numbers as they are needed (or when drivers that need them are
registered.)  It doesn't mean that someone is actually using that number
at that time.

Hope this helps,

greg k-h


-------------------------------------------------------
This sf.net email is sponsored by:ThinkGeek
Welcome to geek heaven.
http://thinkgeek.com/sf
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel