Re: [PATCH RESEND] USB HID: Add ID for eGalax Multitouch used in JooJoo tablet

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




Le 16 août 10 à 17:17, Stéphane Chatty a écrit :


Le 16 août 10 à 15:58, Jiri Kosina a écrit :



thanks for the analysis. How do devices in their report descriptor
describe the fact whether the events should be interleaved by sync or not?

As far as I know, they don't. I know of two multitouch devices that send groups of fingers over several HID messages: - the 3M 22" panel, when there are more than 6 fingers on the panel. You know there are more messages coming when the number of fingers (reported through ContactCount in the first message) is greater than 6. - the eGalax 72xx series, that adds a second message whenever there are two fingers; I am not sure yet how one knows when to wait for a second message. Mathieu might be able to tell us.


Oops... as usual, publishing an opinion is a good way of finding out how it be can wrong :-) I just figured that if ContactMax is available for all devices as well as ContactCount, then there is a way of knowing: - if ContactMax is greater than the number of fingers in the report descriptors, then you know that sometimes you'll get multiple messages. - if ContactCount in a message is greater than the number of fingers in the report descriptors, then you know you'll need to read more messages after this one.

We'll need to check this with all the known devices...

Cheers,

St.

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux