On Mon, Sep 9, 2013 at 4:01 PM, Breton M. Saunders <bms20@xxxxxxxxxxx> wrote: > On 09/09/13 14:12, Benjamin Tissoires wrote: >> >> Hi, >> >> On Mon, Sep 9, 2013 at 2:56 PM, Breton M. Saunders <bms20@xxxxxxxxxxx> >> wrote: >>> >>> Hello, >>> >>> I've written a USB device which supports multiple input devices: >>> * A touch surface digitizer (following Microsoft's specification) >>> * A pen surface digitizer >>> * A mouse emulator >>> >>> In windows each of these interfaces are exposed as a separate top >>> level >>> collection, e.g.: >>> Usage_Page(Generic Desktop) >>> Usage(Mouse) >>> Collection(Application) >>> ... >>> End_Collection >>> Usage_Page(Digitzer) >>> Usage(Touch_Screen) >>> Collection(Application) >>> ... >>> End_Collection >>> Usage(Digitizer) >>> Usage(Pen) >>> Collection(Application) >>> ... >>> End_Collection >>> >>> Now this descriptor works well in Windows; all reporting channels are >>> exposed correctly as hid devices and mouse/multitouch/pen input all works >>> correctly as expected. In linux, however, this is not the case. What I >>> see >>> is that if I drop out the touch/pen functionality then the mouse support >>> works correctly. Likewise, if I drop any pair of other top level >>> collections such that I have exactly one top level collection the system >>> works correctly. >>> >>> Am I missing something here - as in: Have I made an error in my usage >>> of >>> top level collections, or is linux-input's hid support incapable of >>> dealing >>> with multiple top level collections? >> >> If it works under Windows, there are huge chances that your report >> descriptor is good. >> >> However, under Linux, we use the report IDs to split (if required) the >> different inputs. >> The good thing for you is that if I understand correctly, the device >> you are talking about should be handled through hid-multitouch. Since >> kernel v3.10, we have introduced the support of devices showing both a >> digitizer and a pen (they will show up as two input devices). >> >> I would encourage you to test a 3.10 kernel, and/or send me some >> traces of your devices by using hid-replay[1]. This way I will be able >> to test your device on my laptop, and eventually figure out any >> problem. >> >> Cheers, > > Hi Benjamin, > > Thanks for the quick reply. > > 3.10 is a no-go for me; I need to get this working on a vanilla (or > upgraded) version of Ubuntu 12.04; so something more like kernel version > 3.2. (Unfortunately, its what people are using in the field). You can still try to use my backport available here: https://github.com/bentiss/hid-multitouch it _should_ work on a 3.2. You only have to add your VID/PID in hid-multitouch to make it work. > > I will, however, install a more modern kernel to test against; esp. since > I note your HID-replay tool requires 3.6 to test with. well, it requires the module uhid, which is available in 3.6, but also in my backport :) run "modprobe uhid_compat" and run hid-replay against the /dev/hidraw-compatN device. Anyway, if this is too much of a pain, just send me the report descriptor in hexadecimal (and some hexadecimal captures of your events), I'll do the formatting myself. > > Would the correct approach here be to implement a composite USB device and > have separate USB interfaces for mouse, touch and pen for compatibility with > older kernel revisions? I would say no because I don't know what would be the behavior of Windows. But if you don't care about Windows and if this solution works, it's entirely up to you. Cheers, Benjamin -- 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
