[PATCH] finish iso support
castet.matthieu at free.fr
Wed Jun 29 16:57:33 EDT 2005
Duncan Sands wrote:
>>But as I told you in a previous mail, this part could be dropped : we
>>just need to be sure that all packets have the same size.
> Right, but maybe it is useful to have different buffer sizes for iso
> vs bulk. I don't really know - any thoughts on the matter? Maybe we
> should introduce rcv_buf_iso_packets, but calculate the default value
> somehow so it is the same as what you'd get if you'd just used rcv_buf_size
> and done the calculation we do now (corrected to be sure all packets have
> the same size).
The windows driver use a fix number of packets per frame so the size
buffer change if the maxpacket change.
For example at init it try 12*265. Later it see that the size is too low
for the line rate and use 12*795.
So in the first case as 12*265 = 3180 ~ 3392 = 64* 53. But 12*795=9540...
The linux driver used 16*1007.
So if we want to add an extra option for iso, I believe it should be the
number of packets instead of the buffer size.
More information about the Usbatm