[PATCH] SDIO support for Globalscale Dreamplug

Alexander Motin mav at FreeBSD.org
Tue Jul 2 19:45:39 UTC 2013

On 02.07.2013 22:21, Ilya Bakulin wrote:
> On 02.07.13 19:10, Alexander Motin wrote:
>> I think SD world is a terrible mess by itself. I would like to not add
>> more. Functions that suppose card access should take card-specific
>> structure or device as an argument, not a bus ones.
> The problem is that there is a SDIO card which has up to 7 functions,
> but it itself has some characteristics that are available at function 0.
> If we add, say, sdio0 device and store this information there, we end up
> with
> the hierarchy suggested by Ben Gray a year ago.
> The SD-specific functions like CSD/CSR operations are also in the mmc.c
> and considered to be the bus code...
> Or am I missing something obvious here?

That is why I am telling it is a big mess. I don't remember SDIO 
initialization sequence now, but as I can see, for SD cards CSD includes 
information about speed, while SCR includes information about bus width, 
that are probably parts that should be negotiated by the bus, not 
specific peripheral driver.

>> I would try to look for SDIO Bluetooth card. I think such ones still
>> could be found on eBay, and I think there are some specifications for
>> that. Though I've never looked inside.
> The SDIO card found in the Dreamplug has three functions, one of them is
> Bluetooth.
> Will try to find some docs / Linux code for that...

https://www.sdcard.org/downloads/pls/simplified_specs/ -- "SDIO 
Bluetooth Type A Simplified Specification". And for some money it should 
probably possible to get full one, if needed.

Alexander Motin

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