I've tested this and can confirm my LT-20 now works again flawlessly. This really made my day! Ubuntu 8.04 users like myself who want a hassle-free install can get the latest 2.6.26 kernel package from intrepid ( http://packages.ubuntu.com/intrepid/base/ ) and install the deb, and you'll be good to go!
Dan Taylor JWZ wrote: > Good news, everyone! :^) > > The DeLorme Earthmate LT-20 (and LT-40) GPS receivers now work again > under Linux! The new 2.6.26 kernel incorporates a series of patches by > Mike Isely which fix the problems with the supporting driver. > > The full story is a bit more involved, so for anyone interested, please > read on.... > > As near as I've been able to discern, DeLorme has had at least 4 USB- > based GPS receivers which all go by the "Earthmate" name. There is the > original USB-based "Earthmate", 2 variants (details below) of the > "Earthmate LT-20", and the recent "Earthmate LT-40". (It appears that > there may have even been an older RS-232 "Earthmate" as well, but I'm > ignoring any such device here since it is irrelevant to this discussion. > > The 'cypress_m8' Linux kernel module initially (until the 2.6.19 kernel > came out) worked fine with the original USB Earthmate and the 1st > (older) variant of the Earthmate LT-20. > > A patch to the 'cypress_m8' driver by Mike Isely went into what became > the Linux 2.6.19 kernel. For me, it caused my previously-working LT-20 > to stop working. I discovered this (way back in Mar 2007) and, after > some testing, posted about it, including a "quick 'n' dirty" 1-line fix > that made my LT-20 start working again: > > http://www.mail-archive.com/linux-usb- > [EMAIL PROTECTED]/msg52237.html > > Shortly thereafter, I got an email from Mike Isely. He explained that > his patch that got included in creating the Linux 2.6.19 kernel made his > original USB Earthmate GPS receiver work more reliably, preventing some > situation in which the driver was monopolizing his CPU, sometimes even > forcing a reboot. > > We began an email exchange/discussion (which eventually drifted off the > 'linux-usb-devel' mailing list) about fixing the driver properly, to > support both the original Earthmate and the LT-20 version. At that > time, the LT-40 didn't exist. > > We both got distracted for several months doing other things. In that > time, Mike had conveniently purchased an Earthmate LT-20 to do some > testing. We finally got around to resuming the discussion and testing. > Up until late January 2008, neither of us realized that there was such a > thing as a "new" LT-20 variant. Mike came up with a patch to the > 'cypress_m8' driver that worked with his original Earthmate and with his > (new) LT-20. When I tested it, it didn't work with my (old) LT-20, > though. > > We quickly realized that DeLorme had put out a newer version of the > LT-20 but with the same USB 'Product ID' (PID). > > As it turns out, both of the Earthmate LT-20 receivers I own are the > older variant. Mike owns both the old original Earthmate (non-"LT-20") > and the newer variant of the LT-20. > > Once we realized this and reported our respective LT-20 device > capabilities to each other, Mike quickly came up with another patch > which worked perfectly on my older LT-20 devices. Since DeLorme didn't > change the PID between the old and new LT-20 receivers, Mike was forced > to use the device's report of the 'maximum packet size' (32 bytes on the > old LT-20 devices but only 8 bytes on the new LT-20 devices) to discern > the proper way to process the datastream. > > In fact, for anyone interested in the really gory details, here's the > releavant part of the output from 'cat /proc/bus/usb/devices' for every > USB-based Earthmate GPS receiver except the LT-40.... > > The oldest, "original" (non-"LT-20") USB Earthmate: > > T: Bus=02 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=12 MxCh= 0 > D: Ver= 1.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 > P: Vendor=1163 ProdID=0100 Rev= 0.04 > S: Manufacturer=DeLorme Publishing > S: Product=DeLorme USB Earthmate > C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=100mA > I:* If#= 0 Alt= 0 #EPs= 2 Cls=03(HID ) Sub=00 Prot=00 Driver=cypress > E: Ad=81(I) Atr=03(Int.) MxPS= 32 Ivl=6ms > E: Ad=02(O) Atr=03(Int.) MxPS= 32 Ivl=6ms > > The "older" (32-byte) Earthmate LT-20: > > T: Bus=04 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#= 3 Spd=12 MxCh= 0 > D: Ver= 1.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 > P: Vendor=1163 ProdID=0200 Rev= 0.01 > S: Manufacturer=DeLorme Publishing > S: Product=DeLorme USB Earthmate > C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=100mA > I: If#= 0 Alt= 0 #EPs= 2 Cls=03(HID ) Sub=00 Prot=00 Driver=cypress > E: Ad=81(I) Atr=03(Int.) MxPS= 32 Ivl=6ms > E: Ad=02(O) Atr=03(Int.) MxPS= 32 Ivl=6ms > > The "newer" (8-byte) Earthmate LT-20: > > T: Bus=02 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 3 Spd=1.5 MxCh= 0 > D: Ver= 1.10 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 > P: Vendor=1163 ProdID=0200 Rev= 1.11 > S: Manufacturer=DeLorme Publishing > S: Product=DeLorme USB Earthmate > C:* #Ifs= 1 Cfg#= 1 Atr=a0 MxPwr=400mA > I:* If#= 0 Alt= 0 #EPs= 2 Cls=03(HID ) Sub=00 Prot=00 Driver=cypress > E: Ad=81(I) Atr=03(Int.) MxPS= 8 Ivl=10ms > E: Ad=02(O) Atr=03(Int.) MxPS= 8 Ivl=10ms > > The original (non-"LT-20", non-"LT-40") Earthmate has a unique USB PID > ("ProdID=0100"), making it easy to distinguish. As you can see, among other > things, the 2 variants of the LT-20 have different values for "Spd" and for > "MxPS" on both the Input and Output endpoints. In USB parlance, the older > LT-20 is a "full-speed" device (12 Mbps) and the newer LT-20 is a "low-speed" > (1.5 Mbps) device. > > Sometime after those tests were made and Mike's repair patches were > created, both Mike and I purchased the newer Earthmate LT-40. It > appears to be much more like the old LT-20 than the new LT-20. Here's > the output from 'cat /proc/bus/usb/devices' for the LT-40: > > T: Bus=03 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 3 Spd=12 MxCh= 0 > D: Ver= 1.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 > P: Vendor=1163 ProdID=0200 Rev= 0.01 > S: Manufacturer=DeLorme Publishing > S: Product=DeLorme USB Earthmate > C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=100mA > I: If#= 0 Alt= 0 #EPs= 2 Cls=03(HID ) Sub=00 Prot=00 Driver=cypress > E: Ad=81(I) Atr=03(Int.) MxPS= 32 Ivl=4ms > E: Ad=02(O) Atr=03(Int.) MxPS= 32 Ivl=4ms > > More importantly, these new LT-40 GPS receivers work perfectly with the > new 2.6.26 kernel too. > > The bottom line is that the new 2.6.26 kernel properly supports all 4 of > these USB-based DeLorme Earthmate GPS receivers. > > My sincere thanks to Mike Isely for providing these very useful patches > and pushing them upstream for kernel inclusion! He did all the hard > work -- all I did was test and report. > > Hopefully this will be useful to all you Linux-loving Earthmate GPS > users, like me! :^) > > Regards, > Bill Marr > > -- DeLORME Earthmate GPS LT-20 (USBid:1163:0200) doesn't work in Feisty https://bugs.launchpad.net/bugs/111694 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
