Hi I'm not very familiar with the xbox-gamepad driver, but please see below for some comments: On Mon, Sep 23, 2013 at 2:34 AM, Zachary Lund <admin@xxxxxxxxxxxxxxxx> wrote: > I'm apologize ahead of time if this thread isn't appropriate, I'm not > very familiar with mailing lists, especially lkml. I'm also very new > to kernel/module development (as of literally yesterday). Input-drivers are discussed on <linux-input@xxxxxxxxxxxxxxx> (now CC'ed). I recommend subscribing to that list. I also put some driver developers on CC as they are probably more qualified to answer your questions. Note that LKML is a high-traffic list mostly used in CC. Please always CC the driver authors or maintainers. > I was looking into getting the LED working properly for the Xbox 360 > controllers and learning about the basics of a kernel module at the > same time. There were a few things that confused me. I will reference > functions by name and all functions are from the current 3.12 branch. It might be useful to mention the driver in question (it's drivers/input/joystick/xpad.c I guess?). > First, xpad_send_led_command seems to be geared only towards the > "Microsoft X-Box 360 pad". Using xboxdrv as a reference, they use a > completely different packet structure to set the LED status on the > wireless controller which can be seen here: > https://github.com/Grumbel/xboxdrv/blob/master/src/controller/xbox360_wireless_controller.cpp#L66 I don't think the kernel driver supports wireless pads, so it might have a different "wireless optimized" wire-protocol. The driver is USB-only, isn't it? > Second, the driver acts strangely when setting the LED. It calls > xpad_send_led_command during xpad_led_probe during xpad_probe but > there's a chance that a controller might not even be connected if > using the wireless adapter during that time! What? During xpad_probe() a device must be fully functional. What adapter are your talking about? > The only way to seemingly > tell if a controller is connected is by receiving the correct > connection packets. If I use the correct packet structure (which I > ripped almost directly from xboxdrv) and set the led after parsing a > connection packet, the LED seemingly works fine! Sounds reasonable. Do all devices send the connection-packets? If yes, feel free to send a patch which moves LED initialization after receipt of this package. > Third, I'm incredibly new to really low level development. Whenever > loading the module, it finds my wireless adapter but then creates 4 > devices (which seems to mean only 4 controllers are allowed per > wireless adapter), each of which cause a call to xpad_probe. I > couldn't figure out how to tell if other wireless controllers were > already connected to the wireless adapter so I could light up the > correct LED. How would I go about this properly? Ugh? Sorry, but I don't understand what kind of wireless adapter this is? Please give us a bit more information here. If the device is a Bluetooth-device, why use an adapter at all? Cheers David -- 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
