redhat linux usb kerel 2.2.15 howto

After downloading 2.2.15 and applying the USB patch to my redhat 6.0 machine i was unable to compile the usb module for the empeg.

I sent an email to John Ripley (the author) and got this QUICK response:

Change the line (line 52) from:

#include "usb.h"

to:

#include

That fixed it! THANK YOU JOHN!! I now get 221K a second transfers!! (KICK ASS) or 1 cd every 5 minutes :)

If you want (maybe) faster USB, change the number on the line:

#define EMPEG_CAR_NPACKETS 32

to 1024. Really this shouldn't do anything to speed and just wastes a bit of memory, but in practice it gives about 10-20% faster transfers. Something not quite right in the (PC) USB stacks.


- John (from empeg)

(The above may not represent the views of empeg :)

Where is this patch for USB on 2.2.x?

I heard suse had something, but decided 2.4 was gonna be here anyday now so didn;t investigate. Now it looks like it might be a little longer than first envisaged

You can get it at:

http://www.suse.cz/development/usb-backport/

a good "usb" page is http://www.linux-usb.org/



Havn't tried uping the buffers yet, actually i havn't had time to pull the unit out of my car! :)

I tried uping it to 1024 and got this. I will mess around some more with diffrent values...
BTW it worked when i switched it back to 32, and normally i use the --usb option with emptool.
was trying to "keep it simple" :)

[root@dave empeg-car]# emptool --debug 3 /dev/empeg-car
2000 Checking connection [ 0% mpeg-pump v0.03 (19980601)\x0d
2000 Checking connection [Done
2121 Downloading
2121 Starting download [Done
2122 Retrieving tags index [Done
2123 Retrieving databases [ 0% imeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!timeout in state 3 (substate=7567)
!LOCAL_DROPOUT!
4010 Failed to receive database, result -2101

I was able to up EMPEG_CAR_NPACKETS to 64 (from 32) this resulted in 241K a second transfers!

up 20K a second! ! Now if i could only get the same gain going to 1024!!! :)