Am Mittwoch, 20. Juli 2005 22:53 schrieb Hoang Tran:
> The affected modems are PCMCIA cards that use a USB host controller 
> interface to expose a serial device to the Linux operating system. The 
> generic usbserial driver can be used to talk to these devices as if they 
> were serial modems.
> 
> There are 2 potential problems that this work-around resolves:
> 
> 1. The current usbcore and usbserial driver do not correctly recognize 
> the maximum packet size on the inbound bulk endpoint.
> 2. The cards themselves are not advertising the correct maximum data 
> packet size to the usb sub-system on Linux.

Neither. The generic driver uses a buffer of this size for convinience's sake.
Increasing buffer size will increase throughput at the expense of latency.
A proper fix would be to use multibuffer techniques. Do you have a card
and are interested in testing?

        Regards
                Oliver


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