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Date:   Mon, 27 Jun 2022 09:21:20 +0200
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Michael Nazzareno Trimarchi <michael@amarulasolutions.com>
Cc:     Felipe Balbi <balbi@kernel.org>,
        USB list <linux-usb@vger.kernel.org>
Subject: Re: f_hid GET_REPORT extension
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On Mon, Jun 27, 2022 at 09:06:05AM +0200, Michael Nazzareno Trimarchi wrote:
> Hi Felipe and Greg
> 
> I'm starting to write some code to extend the GET_REPORT and let the
> userspace on the device side to pre-fill the answer on this request.
> Right now the answer is always 0. The idea is to create a sysfs
> support to fill reports struct on report request on the host side.
> This will help to
> emulate devices that export features report for example. As far as I
> understand the hidg side just use read and write and read is used to
> extract
> the result of SET_REPORT is that the gadget is properly configured. Is
> it the right direction?

Without code, it is very hard to understand what you are doing here,
sorry.

Also, why sysfs?

thanks,

greg k-h