(unknown)

Hello,

after having a first glance on the MMC/SD driver source, I'm unsure how to handle the following requirement (System: Kernel 2.6.30 on i386).

I'm trying to integrate a SD card with a 'command system expansion' via switch-command (see 'sd card association', 'physical layer simplified spec 2.00', chapter 4.3.12). The additional commands are used to communicate with a specialized controller within the SD card (1), as well as access hidden memory in a secure way (2). Because of the multi functionality (ordinary SD
+ 2 additional features) and not SDIO, I'd like to get a clue where to start?

The first extension might be handled via ioctrl(), so that a user space applications could use it.
The second one should be accessible as a device, which can be mounted to apply a file system.

So there are some questions:

- Do I have to write a complete new driver?
- Can I rely on the existing driver?
- Is there already something implemented?
- Where to place it?
- Do I need a new major device id (in case of a new driver) or just a minor one for mounting?

Another problem might be, that a flash access (read/write) could intercept the extended communication and vice versa?

In the hope to get a little bit of light in the dark,

TIA
Norman