Hi all. I don't know in whose area of liability this lies, so I'm writing this
to both libusb and libftdi MLs.
Long story short, I'm trying to get a stream of data from an FT2232H and I get
a LIBUSB_ERROR_OVERFLOW. (Actually, what I get is an "unknown status 6" string
to my stderr, which is defined in ftdi_stream.c:109).
This error is present when using both ftdi_readstream and ftdi_read_data.
The reason why I am writing this letter is that the libusb documentation says
this:
>you will never see an overflow if your transfer buffer size is a multiple of
>the endpoint's packet size
...and this is exactly what libftdi does:
int bufferSize = packetsPerTransfer * ftdi->max_packet_size; (ftdi_stream.c:153)
I checked, and the max_packet_size field is populated correctly (as far as
lsusb can tell): the chip declares the endpoint's packet size as 512 bytes, and
this is what max_packet_size equals to.
I found a 5 years old report on a similar problem with another FTDI chip:
http://libusb.6.n5.nabble.com/libusb-bulk-transfer-and-overflow-errors-td2802636.html
but it sort of ended on nothing.
I'm using OpenSuSE 13.2 x64 with 3.16.7-7-desktop kernel, libusb 1.0.19-2.1.2
and the latest version of libftdi (f6ac3c2).
Daniil
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