I own a G25, Can you write out some of the knowledge you have acquired? On Fri, Mar 14, 2008 at 7:52 PM, chris guirl <thelusiv@xxxxxxxxx> wrote: > On Fri, Mar 14, 2008 at 5:42 AM, Jiri Kosina <jkosina@xxxxxxx> wrote: > > thanks for your mail, I have added Jean-Philippe to CC, who has sent me > > some time ago debugging information for this wheel, but I unfortunately > > didn't yet had time to look into that in more detail. > > Which wheel, the DFP or the G25? Either way they are similar in many > ways so better support for one would improve support for the other. > I'm interested to see this information. There has been some discussion > of the G25 on the forums at vdrift.net. > > > Regarding the HID code -- currently, all device-specific stuff for HID > > devices is implemented as quirks in hid code -- please see > > drivers/hid/hid-*quirks* and drivers/hid/usbhid/hid-quirks*. This is not a > > solution that works well in long-term though, and Jiri Slaby (also added > > to CC) is currently rewriting the HID core code, so that it will work as a > > proper bus, so individual drivers could work nicely with that. Once this > > is done, all the current quirks will be converted to HID-bus drivers. > > I've looked through the quirks code and I have some suggestions for > things that can be changed. First, the Vendor/product IDs of the > wheels are not present. When the devices power up they assume VID:PID > 0x046d:0xc294 which there is a line for in > drivers/hid/usbhid/hid-quirks.c: > > #define USB_DEVICE_ID_LOGITECH_WHEEL 0xc294 > > This is used by the Logitech Formula Force or Driving Force wheel, and > a legacy mode on the DFP & G25. To use the DFP or G25 in their native > modes, they must be sent a command [0xf8, 0x01] or [0xf8, 0x10] > respectively. Once these wheels receive this command, they simulate a > detach and reattach as 0x046d:0xc298 and 0x046d:0xc299 respectively. > These VID:PID combinations are not handled in the kernel at all. At > the very least they need to be assigned the same quirks as the Driving > Force. > > When a Driving Force/Formula Force wheel is detected the device needs > to be probed with the native mode commands to see if it will switch > into DFP or G25 mode. If these modes work, then it is possible to send > the wheels some other commands to enable full rotation of the wheel. > By default only 200 degrees of rotation is available, but both the DFP > and G25 can be switched to allow up to 900 degrees of rotation. I > think there should be a user-land tool to change settings on the wheel > such as this. > > > Depends on how massive your changes are going to be, you could either > > coordinate with Jiri so that no effort is wasted, or you can just send me > > a patch with simple quirks addition, and it will get converted into hidbus > > driver later. > > If there is a rewrite due then it may be best to work with Jiri so I > can make my changes work with his, no sense in patching twice. > > In addition to HID code, I think I'll need to make some changes to the > joydev driver, as some other things need to be addressed (such as > splitting the gas and brake axis up into separate, independent axes). > Currently I am able to send raw commands to my DFP to make it change > modes, but the /dev/input/jsX device disappears when I do this, so > some other tweaks may be needed on the joystick end of things. > > I'll be out of town this weekend so not working on anything yet, but > please send any ideas along as I hope to get started next week. > Thanks. > > Chris > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-input" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Thanks, Richie Ward -- Thanks, Richie Ward -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
