Op 16-06-10 19:58, Sylvain Lamontagne schreef: > Hi Mr Piel, > Last october you sent a patch to correctly identify the GPS module on > the Dell mini 1010. > http://www.kernel.org/pub/linux/kernel/people/gregkh/usb/2.6/2.6.32-rc3/usb-cp210x-add-support-for-the-dw700-uart.patch > > I own a Dell Mini 1010 and would like to know if the status change on > this. Because while sending the patch, you also wrote "(I haven't > managed to use the GPS under > Linux yet, though)" > > I would like to have the GPS module to work and I would be willing to > work on developing the driver if it's not a too big task. I have > already wrote some driver in the past but they were mostly character > device never USB... it was for academic learning. I have some book > that can surely help me, but if someone could guide me in the process > I would really appreciated this. Unfortunately, so far I haven't managed to get any data back from the GPS under Linux. I haven't dedicated much time to it yet though... So far here is the info I've assembled: * Behind the UART device (ttyUSB0), lays the actual GPS chip, a broadcom BCN4750, aka Barracuda. * In windows, this corresponds to COM3, to which the dell location utility is connected and agglomerates data with WIFi info to retransmit as a fake GPS on COM4. * With a logging software, I could record the typical transmission on COM3. It looks binary, definitely not the standard NMEA. Unfortunately, replaying it as it under Linux did not lead to any response from the GPS chip. * Here [1] is an interesting PDF from freescale about their platform, which runs Linux and also has a BCM4570. See page 227. In particular they mention a second interface via GPIO to turn on/off the chip. On the Dell 1010, maybe this is done via the functionalities used in the compal-laptop or dell-laptop drivers. * Freescale also mentions that the low-level part of the driver's source is available (but I didn't have time to look for it yet). They talk specifically about the core driver called "glgps_freescaleLinux", and the low-level called "gps_gpiodrv.ko". Finding these could greatly help. I've looked a bit at their development kit but so far couldn't find the source, it very messy :-( Maybe you could try to ask help on the gpsd mailing list, or on the Dell Linux support forum, someone could have additional info. See you, Eric [1] http://openembed.com/files/pdk15_imx35__Linux_RM.pdf -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
