usb_set_intfdata usage for two subdrivers

usb_set_intfdata usage for two subdrivers

[Antti Palosaari]

I am trying to implement DVB USB device smartcard reader support using 
USB-serial. The main problem is now that both DVB-USB and USB-serial 
uses interface data (usb_set_intfdata / usb_get_intfdata) for state.

Is there any common solution to resolve issue easily?

regards
Antti

-- 
http://palosaari.fi/

Re: usb_set_intfdata usage for two subdrivers

[Greg KH]

On Mon, Aug 29, 2011 at 02:30:26AM +0300, Antti Palosaari wrote:
> I am trying to implement DVB USB device smartcard reader support
> using USB-serial.

Really?  Why?  That doesn't seem to make sense, please explain more.

> The main problem is now that both DVB-USB and
> USB-serial uses interface data (usb_set_intfdata / usb_get_intfdata)
> for state.
> 
> Is there any common solution to resolve issue easily?

No two drivers can bind to the same USB interface, so of course they
would interfere.

Care to explain the problem in more detail to see if there is a better
way to do all of this?

greg k-h

Re: usb_set_intfdata usage for two subdrivers

[Antti Palosaari]

On 08/29/2011 03:36 AM, Greg KH wrote:
> On Mon, Aug 29, 2011 at 02:30:26AM +0300, Antti Palosaari wrote:
>> I am trying to implement DVB USB device smartcard reader support
>> using USB-serial.
>
> Really?  Why?  That doesn't seem to make sense, please explain more.

Since it is old style serial smartcard reader, not CCID PC/SC as new 
readers. I see it a little bit overkill to register virtual HCI and 
virtual CCID device though it sounds interesting.

There is already one such similar driver, iuu_phoenix, but without DVB 
support ;) Consider situation I have iuu_phoenix integrated to USB DVB 
device. Both using same USB enpoint, sharing hardware resources of 
communication.

>> The main problem is now that both DVB-USB and
>> USB-serial uses interface data (usb_set_intfdata / usb_get_intfdata)
>> for state.
>>
>> Is there any common solution to resolve issue easily?
>
> No two drivers can bind to the same USB interface, so of course they
> would interfere.
>
> Care to explain the problem in more detail to see if there is a better
> way to do all of this?
>
> greg k-h


regards
Antti

-- 
http://palosaari.fi/

Re: usb_set_intfdata usage for two subdrivers

[Oliver Neukum]

Am Montag, 29. August 2011, 05:54:36 schrieb Antti Palosaari:
> On 08/29/2011 03:36 AM, Greg KH wrote:
> > On Mon, Aug 29, 2011 at 02:30:26AM +0300, Antti Palosaari wrote:
> >> I am trying to implement DVB USB device smartcard reader support
> >> using USB-serial.
> >
> > Really?  Why?  That doesn't seem to make sense, please explain more.
> 
> Since it is old style serial smartcard reader, not CCID PC/SC as new 
> readers. I see it a little bit overkill to register virtual HCI and 
> virtual CCID device though it sounds interesting.
> 
> There is already one such similar driver, iuu_phoenix, but without DVB 
> support ;) Consider situation I have iuu_phoenix integrated to USB DVB 
> device. Both using same USB enpoint, sharing hardware resources of 
> communication.

Look at struct dvb_usb_device.
It has a struct input_dev embedded. I suggest you also add a serial
device for smart cards.

	HTH
		Oliver