isochronous support broken?
castet.matthieu at free.fr
Sun Jan 8 16:48:55 EST 2006
Duncan Sands wrote:
> Hi Alistair,
> -ENOSPC This request would overcommit the usb bandwidth reserved
> for periodic transfers (interrupt, isochronous).
> Interesting. What kernel version is this (I noticed some bandwidth changes
> going into 2.6.15)? Do you have other iso devices connected at the same time?
For me (eagle) with the default configuration of usbatm I use 121% of
the bandwidht 
I need to reduce the number of iso packet via module parameter.
T: Bus=02 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=12 MxCh= 2
B: Alloc=1091/900 us (121%), #Int= 1, #Iso= 4
D: Ver= 1.10 Cls=09(hub ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
P: Vendor=0000 ProdID=0000 Rev= 2.06
S: Manufacturer=Linux 2.6.15 uhci_hcd
S: Product=UHCI Host Controller
C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr= 0mA
I: If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub
E: Ad=81(I) Atr=03(Int.) MxPS= 2 Ivl=255ms
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