Hello Clemens
On 11/30/2016 11:41 PM, Clemens Ladisch wrote:
Jiada Wang wrote:
since commit 57e6dae1087bbaa6b33d3dd8a8e90b63888939a3 the expected packetsize is always limited to
nominal + 25%. It was discovered, that some devices
Which devices?
It was a LG nexus
have a much higher jitter in used packetsizes than 25%
How high? (Please note that the USB specification restricts the jitter
to at most one frame in consecutive packets.)
the nominal packet size was somewhere around 176bytes
+25% would result in max expected packets to be ~220bytes
We observed some packets exceeding this size (256byte)
which caused the babble and dropping of that packets.
Thanks,
Jiada
which would result in BABBLE condition and dropping of packets.
A better solution is so assume the jitter to be the nominal packetsize
This solution is better for this one particular device, but how does it
affect normal devices, or the Scarlett 2i4 on EHCI affected?
Regards,
Clemens
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