To be honest, I had not considered a usbserial interface. But after taking some time to look at other drivers in the serial group, I think it would be a good fit. The only have one concern at this time. When copying data into to the tty buffer for the user to read, it looks like it can drop data if it is too full. Is that a problem in practice? If so, I must ensure that the data received makes it completely into the buffer or not at all. Garmin usb data has no start or stop delimiters to identify a packet, so the user would have no idea where to find the start of the next packet. Other than that it should work fine.
There is an added advantage to using a usb-serial interface. The usb data could be converted to the standard Garmin serial format so that it would make the usb device look just like an older serial one if the user desired. I have already started on a usb-serial version and I will post it shortly. Thanks, Marty On Wed, 3 Nov 2004 08:12:13 -0800, Greg KH <[EMAIL PROTECTED]> wrote: > On Wed, Nov 03, 2004 at 05:51:50AM +0000, Marty Boos wrote: > > > > Hello, > > > > I have attached a patch to the 2.6.9 kernel containing a driver for > > Garmin GPS devices (www.garmin.com). I have only tried it with a GPS18 > > so far and I would invite others with different devices to join me in > > development and testing. > > > > I would like ideas on the following: > > > > Handling interrupt in data: it comes fast and I must buffer it up > > so that the user has a chance to get the data out. Is there a better > > way to ensure that packets won't be lost? > > > > Reading data: Right now read (bulk in) and ioctl (interrupt in) rely > > on the user providing a sufficiently large buffer to handle the max > > packet size. > > > > I can provide some more detailed information to anyone interested in > > helping. > > I thought this driver used the usb-serial interface, not it's own minor > number interface. Why would that interface not work properly for this > type of device? > > thanks, > > greg k-h > ------------------------------------------------------- This SF.Net email is sponsored by: Sybase ASE Linux Express Edition - download now for FREE LinuxWorld Reader's Choice Award Winner for best database on Linux. http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
