[U-Boot] [PATCH] MTD/SPI/FLASH: add support for Ramtron FRAMs using SPI

[Mike Frysinger]

On Thursday, August 26, 2010 01:57:23 Reinhard Meyer wrote:
> Dear Mike Frysinger,
> > #if defined(CONFIG_SPI_FRAM_RAMTRON)
> > # define IDCODE_LEN 10
> > #else
> > # define IDCODE_LEN 5
> > #endif
> 
> OK, see below. Can't we have it 10 generally? The impact should be
> negligible?

hrm, i guess ... but i didnt even really like raising it to the 5 for one 
specific family ...

> > for the second, what do you get back when you issue the idcode ?  0xff ? 
> > we already have a fall back case for this with stmicro, so perhaps we
> > should
> >
> > generalize this further too.  after the vendor id switch statement, we do:
> 
> If MISO has no pull-up the result is indeterminate, the chip simply lets
> MISO float when it does not honor the read-id command.
> 
> I'll add a comment to that file that a pull-up is required for non-standard
> devices to be detected. Otherwise, depending on random noise, a false
> detection of a standard device is not entirely impossible.

that sounds reasonable to me
-mike
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 836 bytes
Desc: This is a digitally signed message part.
Url : http://lists.denx.de/pipermail/u-boot/attachments/20100826/10488897/attachment.pgp