Re: [PATCH v2 1/3] usb: gadget: ccid: add support for USB CCID Gadget Device

[Andrzej Pietrasiewicz]

Mi Marcus,

W dniu 26.05.2018 oÂ23:19, Marcus Folkesson pisze:
> 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>
> ---

>   
> +config USB_CONFIGFS_CCID
> +	bool "Chip Card Interface Device (CCID)"
> +	depends on USB_CONFIGFS
> +	select USB_F_CCID
> +	help
> +	  The CCID function driver provides generic emulation of a
> +	  Chip Card Interface Device (CCID).
> +
> +	  You will need a user space server talking to /dev/ccidg*,
> +	  since the kernel itself does not implement CCID/TPDU/APDU
> +	  protocol.

Your function needs a userspace daemon to work.
It seems you want to use FunctionFS for such a purpose
instead of creating a new function.

Andrzej