[U-Boot] [PATCH 1/4] mmc: Change board_mmc_getcd() signature.

Stefano Babic
2011-12-05T10:54:18Z

On 05/12/2011 11:00, Thierry Reding wrote:
> * Marek Vasut wrote:
>>> The new API no longer uses the extra cd parameter that was used
>>> to store the card presence state. Instead, this information is
>>> returned via the function's return value. board_mmc_getcd()
>>> returns -1 to indicate that no card-detection mechanism is
>>> implemented; 0 indicates that no card is present and 1 is
>>> returned if it was detected that a card is present.
>>>
>>> Signed-off-by: Thierry Reding
>>> <thierry.reding@avionic-design.de>
>>
>> A silly question -- why do we need this change ? Can you explain
>> it in the changelog of V2 too?
>
> It's the first step in implementing card-detection. I discussed
> this with Andy and he came up with the idea that board_mmc_getcd()
> should really have had the mmc parameter as first argument in the
> first place instead of the cd parameter.

Ok, I get it now.

> Furthermore, the cd parameter is used inconsistently in individual
> implementations. After some discussion we came to the conclusion
> that the cd parameter wasn't required at all and the same
> information can be represented in the return value. The whole
> discussion is in this thread:
>
> http://lists.denx.de/pipermail/u-boot/2011-November/110180.html
>
> It's not really a necessary change, but it makes board_mmc_getcd()
> much more consistent with other MMC-related functions.
>
> Perhaps this last sentence would be a good explanation to put in
> the v2 commit message?

Ok, thanks - this explains much better which is your intention for the
patchset. It is also not bad to add a reference to the above thread.

Best regards,
Stefano Babic

--
=====================================================================
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: office at denx.de
=====================================================================