Re: [PATCH v3 1/3] usb: gadget: ccid: add support for USB CCID Gadget Device

[Marcus Folkesson]

Hi Filipe,

On Fri, Jun 22, 2018 at 06:48:23PM +0200, Marcus Folkesson wrote:
> Hi Filipe,
> 
> On Mon, Jun 18, 2018 at 11:22:04AM +0300, Felipe Balbi wrote:
> > 
> > Hi,
> > 
> > Marcus Folkesson <marcus.folkesson@xxxxxxxxx> writes:
> > > Hi Felipe,
> > >
> > > Should I send out v4 or what do you think?
> > 
> > sorry for the delay, have been busy with other tasks.
> > 
> 
> It is no hurry :-)
> 
> > > On Wed, May 30, 2018 at 04:04:15PM +0200, Marcus Folkesson wrote:
> > >> Hi Filipe,
> > >> 
> > >> On Wed, May 30, 2018 at 03:28:18PM +0300, Felipe Balbi wrote:
> > >> > Marcus Folkesson <marcus.folkesson@xxxxxxxxx> writes:
> > >> > 
> > >> > > Chip Card Interface Device (CCID) protocol is a USB protocol that
> > >> > > allows a smartcard device to be connected to a computer via a card
> > >> > > reader using a standard USB interface, without the need for each manufacturer
> > >> > > of smartcards to provide its own reader or protocol.
> > >> > >
> > >> > > This gadget driver makes Linux show up as a CCID device to the host and let a
> > >> > > userspace daemon act as the smartcard.
> > >> > >
> > >> > > This is useful when the Linux gadget itself should act as a cryptographic
> > >> > > device or forward APDUs to an embedded smartcard device.
> > >> > >
> > >> > > Signed-off-by: Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
> > >> > 
> > >> > this could be done entirely in userspace with functionfs, why do we need
> > >> > this part in the kernel? It does very little.
> > >> 
> > >> Andrzej pointed this out, and I actually do not have any good answer
> > >> more than that the userspace application could be kept small and the
> > >> important configuration of the CCID device is done with well (I hope)
> > >> documented configfs attributes.
> > 
> > can we use existing open source applications without modification by
> > accepting this glue layer?
> 
> 
> If you mean existing open source application to talk to the "daemon", the answer is
> yes. I have been using PCSC-lite and OpenSC on Linux, and PCSC on
> Windows to communicate with the smartcard.
> 
> If you mean existing application as the "daemon", the answer is probably
> no.


Just sending a friendly ping on this one.
I've sent out v4 as I had it prepared for a long time, just to catch
comments in the meanwhile, but none so far.

> 
> > 
> > -- 
> > balbi
> 
> Thanks,
> 
> Best regards
> Marcus Folkesson
> 

Thanks,

Best regards
Marcus Folkesson
>