Hi Xiaofan, Thanks for the suggestion.
I cross-compiled libFTDI with -Wcast-align and indeed I got an error as indicated in the libusbx discussion. However, after looking through the libusbx and libftdi code to see where these sensitive functions are called I found: - libftdi doesn't use them directly, - only two of them are used in libusbx and they are not dangerous. I guess there would be problems if an incoming buffer is cast to struct libusb_control_setup directly. However, I didn't find anything like this in the code. I will keep digging. Best regards, Victor On 01/08/13 09:55, Xiaofan Chen wrote: > On Thu, Aug 1, 2013 at 4:20 PM, Victor Cionca <[email protected]> > wrote: >> I ran into some problems running an FTDI application on a MIPS platform. >> >> I have an embedded device using an Atmel microcontroller. The uC is >> programmed over SPI via an FTDI chip, using bit-banging. >> >> I have an application that does the programming and it works well on my >> Linux machine (Kernel 3.2.0-0.bpo.4-686-pae, libftdi 1-1.0, libusb-1.0.16). > There is no libusb-1.0.16, do you mean libusbx-1.0.16? > >> I cross-compiled the application (and the libftdi, confuse and libusb >> libraries) for a MIPS CPU, Atheros AR9330 (it's the TPLink MR3020 >> router, running OpenWrt). Used the same libraries and the kernel is 3.3.8. >> >> While the application runs fine (so it cross compiled well), it seems >> unable to communicate properly with the board. I send data and either >> get all zeroes or all FFs. I enabled usb debugging but the output is >> identical between the two machines - the only difference being in the >> usbi_handle_transfer_completion, with different addresses, but I guess >> that's normal. >> > I do not know if this has anything to do with a potential libusb bug > which may happen under some embedded Linux application. > > https://github.com/libusbx/libusbx/issues/120 > http://libusbx.1081486.n5.nabble.com/Libusbx-devel-Possible-alignment-issues-with-struct-libusb-transfer-buffer-pointer-td1458.html > > -- libftdi - see http://www.intra2net.com/en/developer/libftdi for details. To unsubscribe send a mail to [email protected]
