Re: [PATCH 0/1] HID: User-space HID I/O driver (UHID)

[David Herrmann <dh.herrmann@googlemail.com>]

Hi Joao

On Wed, May 2, 2012 at 9:09 PM, Joao Paulo Rechi Vita
<jprvita@openbossa.org> wrote:
> On Mon, Apr 30, 2012 at 12:27 PM, David Herrmann
> <dh.herrmann@googlemail.com> wrote:
>> Hi
>>
>> This implements a hid_ll_driver user-space interface similar to uinput f=
or the
>> input devices. It allows to implement the HID transport-layer in user-sp=
ace as
>> required by Bluetooth Low-Energy (HoG).
>>
>> This is my "first final revision" for the module. Please review and test=
.
>> Changes from the previous RFCs include:
>> =A0- The feature-report mechanism is now implemented
>> =A0- Several min_t() fixes
>> =A0- Minor coding-style issues
>>
>> I did not change __attribute__((__packed__)) to __packed as the latter o=
ne is
>> not provided to user-space.
>>
>> If there are any more issues, please tell me. And for the record, the Ho=
G devs
>> told me that they are working since several months with it now so we hav=
e a real
>> user-space application that needs it ;)
>>
>> If there are no more issues (which i doubt) I can also resend this split=
ted into
>> multiple patches.
>>
>
> Thanks for your work, David. I'll test and review this new version.
> Did you find out the what is the problem when passing BUS_BLUETOOTH on
> the 'bus' field of the create request?

I've spent some time looking into that but I haven't found the
problem, yet. Maybe Jiri can comment here.

> Also, how does the HID subsystem differentiate from HID protocol
> versions? We've just found out that HoG exposes what HID protocol
> version the device implements, is it the case of having an extra field
> on the uhid_create_req structure to pass this information, or is it
> already present on the HID descriptor (sorry for my limited knowledge
> on the HID protocol itself)?

There is already a "version" field in UHID_CREATE. It isn't mandatory,
though, so setting it to 0 works. I even think the HID core doesn't
even look into that value except for printk messages.

> --
> Jo=E3o Paulo Rechi Vita
> Openbossa Labs - INdT

Thanks
David