Hi all, This patchset is gonna improve the card's init sequence by exposing some caps to DT. The basic idea is to skip sending specific init cmd inspired by Carlo Caione's commit[0]. To make it possible, I firstly expose Carlo's MMC_CAP2_NO_SDIO to DT and extend two new caps for similar usage of sd and mmc. We probably need it because for most of the boards, each of the slots should have a specific function when designed. It's impossible for one slot which can either to be used as eMMC or a SD card for a given board. The same for SDIO case. We could have two ways to improve it A) Skip sending specific commands if knowing we don't support the specific card type. B) Allow sending specific commands if knowing we do support the specific card type. A) and B) shouldn't have difference, but I take A) as the final one as it looks more consistent with Carlo's way, which does not seem to break anything as possible. The only roadblock for this patchset to be landed should be the improvement we gain from it. Theoretically sdio-card doesn't get improvment as it's already in the first place to be attached. But considering the sd and (e)MMC case, we should gain more benifit from it. >From the test, we can save nearly 2ms for attaching emmc against the original 8ms. And we gain more than 30us improvement for sd card for each insert. [0]: http://permalink.gmane.org/gmane.linux.kernel.mmc/34774 Shawn Lin (4): Documentation: mmc: add description for new caps mmc: core: expose MMC_CAP2_NO_SDIO to dt-binding mmc: core: add cap-no-sd and cap-no-mmc properties mmc: core: improve initialization flow Documentation/devicetree/bindings/mmc/mmc.txt | 3 +++ drivers/mmc/core/core.c | 10 +++++----- drivers/mmc/core/host.c | 6 ++++++ include/linux/mmc/host.h | 2 ++ 4 files changed, 16 insertions(+), 5 deletions(-) -- 2.3.7 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
