Regarding writing a PCMCIA client driver for a multifunction device

[monali.katkar at wipro.com]

Hello Dominik,
Thanks a lot for your reply .

My card is identified as
Socket 0:
product info: "CF CARD", "GENERIC", "", ""
manfid: 0xXXXX, 0xXXXX
function: 2 (serial)
For a multifunction card I think it should report function: 0
(multifunction). M I correct ?

What do you mean by pseudo multifunction card ?

I also want to know the following -

1. In PCMCIA, does CS handle the interrupts? 
  If not then which module services the interupts and routes the
interrupts to the appropriate client driver?

2. For a PCMCIA card which has two functions USB and the UART what
happenes if both the function raise interrupt simultaneously, whose
interrupt handler is invoked -  PCMCIA client driver for UART function
or PCMCIA client driver for USB function. Are both the interrupt
handlers invoked and in what sequence .

Regards,
Monali.



> -----Original Message-----
> From: Dominik Brodowski [mailto:linux at dominikbrodowski.net]
> Sent: Wednesday, December 07, 2005 5:34 PM
> To: Monali Vishnu Katkar (WT01 - Semiconductors & Consumer
> Electronics)
> Cc: linux-pcmcia at lists.infradead.org
> Subject: Re: Regarding writing a PCMCIA client driver for a
> multifunction device
>
>
> Hi,
>
> On Tue, Nov 29, 2005 at 10:13:48AM +0530,
> monali.katkar at wipro.com wrote:
> > I have a 16 bit Compact flash card. This card  facilitates a
> > multifunction bridge between a host interface (such as on a
> PC, PDA )
> > and both a USB 1.1 (Full Speed, Low Speed) host interface
> and a richly
> > featured UART.   I want to write a driver to support this
> multifunction
> > device on kernel 2.6 .
>
> It'd be interesting to know the output of
> 	tree /sys/bus/pcmcia/
> for this device, first, to determine whether it is a true
> multi-function device or a pseudo multi-function device.
>
> Also, the UART part of it might be able to be handled by serial-cs?
>
> > a) Could you suggest me the changes that i would need to do if the
> > device is multifunction device .  Are there any sample
> multifunction
> > PCMCIA drivers. Pointers to any code /documents would help .
>
> true multifunction pcmcia devices are handled by:
> drivers/ide/legacy/ide-cs.c drivers/net/pcmcia/3c574_cs.c
> drivers/net/pcmcia/3c589_cs.c drivers/net/pcmcia/pcnet_cs.c
> drivers/net/pcmcia/smc91c92_cs.c
> drivers/net/wireless/hostap/hostap_cs.c
> drivers/serial/serial_cs.c
>
> pseudo multifunction pcmcia devices are handled by:
> drivers/net/pcmcia/axnet_cs.c drivers/net/pcmcia/fmvj18x_cs.c
> drivers/net/pcmcia/pcnet_cs.c
> drivers/net/pcmcia/smc91c92_cs.c
> drivers/net/pcmcia/xirc2ps_cs.c drivers/serial/serial_cs.c
>
> > b)How do i look if the card functions can be used
> independently . What
> > in the CIS information is required to support this.
>
> Well, the output of	tree /sys/bus/pcmcia/	should be a first
> indication.
>
> > c) How to reserve resources for each function on this card usage of
> > pcmcia_request_io() and realease_io.
>
> the _attach() / _probe() callbacks are called independently
> for each function, be it real or pseudo multifunction
> devices. The PCMCIA core correctly knows which one it is, and
> sets up the resources accordingly. However, you need to
> request the proper ones ;)
>
> Hope this helps,
> 	Dominik
>


Confidentiality Notice

The information contained in this electronic message and any attachments to this message are intended
for the exclusive use of the addressee(s) and may contain confidential or privileged information. If
you are not the intended recipient, please notify the sender at Wipro or Mailadmin at wipro.com immediately
and destroy all copies of this message and any attachments.