Hi Mike,
On Fri, Apr 23, 2010 at 11:08:10AM -0400, Mike Frysinger wrote:
On Friday 23 April 2010 04:43:07 Wolfgang Wegner wrote:
However, one of the things I had to change was the dummy data sent out by SPI for read-only transactions. The original driver had all zeros, for SD/MMC all ones (0xFF) is needed.
Is such a change acceptable, or is there any configuration option/flag I could use?
if it isnt part of the SPI/MMC spec, use a config option named like IDLE_VAL.
the problem exists in the (coldfire) SPI driver, not in the MMC/SD code. (For SD, the spec IMHO clearly states 0xFF for all idle transfers.)
changing the default to 0xff is OK i think.
I could add CONFIG_SPI_IDLE_VAL and default it to 0x0 in the coldfire SPI driver. In case one wants to use MMC/SD with this driver, one could then add CONFIG_SPI_IDLE_VAL as 0xFF in the board to override it. (Only pitfall is that the current 0x0 is used for 8- as well as 16-bit transfers...)
ok?
-mike
Regards, Wolfgang