Re: Plan for adding XD support in mtd layer

["Jörn Engel" <joern@logfs.org>]

On Thu, 26 November 2009 01:22:45 +0200, Maxim Levitsky wrote:
> > 
> > According to FMTP140E.PDF, CIS and IDI are stored in sector 0 or the
> > first non-defective block.  In other words, it can be read and written
> > normally, without any magic.  Certainly not the atrocities I tried not
> > to remember.
> I wish I had the spec.

It used to be semi-free.  You could download it for your name and
address.  But I believe I'm not legally able to forward it to you and
the official site seems to be down.  Most of the information can also
be found here:
http://www.win.tue.nl/~aeb/linux/smartmedia/SmartMedia_Format.pdf
And there seems to be a copy available at pudn:
http://en.pudn.com/downloads137/doc/fileformat/detail585996_en.html

> I don't know the format of the CIS, and I know that special command is
> used to query the ID.
> CIS these days isn't used for anything and I hoped not to touch that
> thing.

:)

> I wont argue on that one with you, but why not to add the new field.
> It is quite generic, it could be card vendor information or so?
> Few bits of custom information to assign for each card no?
> 
> 
> I am taking about these:
> 
> struct xd_card_id1 {
> unsigned char maker_code;
> unsigned char device_code;
> unsigned char option_code1;
> unsigned char option_code2;
> } __attribute__((packed));
> 
> struct xd_card_id2 {
> unsigned char characteristics_code;
> #define XD_CARD_CELL_TYPE_MASK   0xc0
> #define XD_CARD_MULTI_BLOCK_MASK 0x30
> 
> unsigned char vendor_code1;
> unsigned char size_code;
> unsigned char vendor_code2;
> unsigned char vendor_code3;
> } __attribute__((packed));
> 
> struct xd_card_id3 {
> unsigned char vendor_code1;
> unsigned char vendor_code2;
> unsigned char id_code;
> unsigned char vendor_code3;
> } __attribute__((packed));
> 
> 
> Are these 32 bit values copied from CIF?
> 
> These values are read using commands:
> 
> XD_CARD_CMD_ID1         = 0x90,
> XD_CARD_CMD_ID2         = 0x91,
> XD_CARD_CMD_ID3         = 0x9a
> 
> 
> I need especially the xd_card_id1.device_code because this specifies the
> media type, but xd_card_id3.id_code is used to detemine if media is
> smartmedia or XD.

If you add this information to a struct xD_card and have mtd->priv point
to said structure, wouldn't that be enough for your purposes?

Jörn

-- 
The cheapest, fastest and most reliable components of a computer
system are those that aren't there.
-- Gordon Bell, DEC labratories