On 11/24/2016 08:11 AM, jry wrote: > I would like to ask if there is anyone who knows libftdi or libusb and would > be able to help me identify one problem in libftdi library. In asix-sigma > driver > I'm reading large data blocks from FT245RL with asynchronous transfer, > using ftdi_read_data_submit() and ftdi_transfer_data_done(). > > Unfortunately libftdi doesn't return with timeout when it receives smaller > than > required data frame. It simply hangs in ftdi_transfer_data_done(): > http://developer.intra2net.com/mailarchive/html/libftdi/2016/msg00118.html > > ftdi_transfer_data_done() implementation: > http://developer.intra2net.com/git/?p=libftdi;a=blob;f=src/ftdi.c;h=0b26a7a8b698ce201f7a11797700376db3525820;hb=HEAD#l1736
It looks like libftdi, while it does set a timeout on the async transfer, never actually checks whether the condition occurred in the transfer's callback. The timeout itself is a default value, hardcoded, which cannot be changed or configured by client code. > I'm not familiar with libftdi and libusb libraries and any any advice would > be most welcome. Clearly, libftdi will not handle this situation you need to deal with. Since libftdi is a thin and unnecessary abstraction layer on top of libusb which provides no values other than configuring the FTDI chip (which is trivial), I recommend getting rid of it altogether. Simply convert the driver to libusb calls instead. You can use the current calls to libftdi and its libusb actions as a guide, or check the code in many other libsigrok drivers. -- Bert Vermeulen b...@biot.com ------------------------------------------------------------------------------ _______________________________________________ sigrok-devel mailing list sigrok-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sigrok-devel
