[PATCH v2 0/6] Add support of inverting power control and some minor cleanup

Jaehoon Chung jh80.chung at samsung.com
Mon Aug 8 03:24:31 PDT 2016

Hi Shawn,

On 08/07/2016 10:33 AM, Shawn Lin wrote:
> By default, dw_mmc outputs high level voltage to indicate powering
> up the card and outputs low level vcltage to indicate powering
> off the card. But that is not always correct. The power io should
> be able to control different kind of hw components to supply or
> cutoff power to the card. We have boards that need this patchset
> to make the power control correct. Meanwhile let's expose it to
> DT for board-specific usage.

I have a question for this patch-set. Does DWMMC IP support to invert ON/OFF at Power Enable register?
Hmm..Well, if use the DW_MMC_CARD_PWR_INVERT, it should also be the similar behavior with Quirks.

Other flags are related with dwmmc IP. But this flag (DW_MMC_CARD_PWR_INVERT) is not related with IP side.
I understood why you needs to add this flag..Is rockchip designed to invert the power controlling?

But it's not general case. We can discuss about this.

Best Regards,
Jaehoon Chung

> Changes in v2:
> - fix copy-paste err and typo
> Shawn Lin (6):
>   dt-bindings: rockchip-dw-mshc: add description of
>     rockchip,power-invert
>   mmc: dw_mmc: cleanup power setting of set_ios callback
>   mmc: dw_mmc: split out dw_mci_set_power
>   mmc: dw_mmc: split out dw_mci_set_power_reg
>   mmc: dw_mmc: support inverted power control
>   mmc: dw_mmc-rockchip: add parsing of power control from DT
>  .../devicetree/bindings/mmc/rockchip-dw-mshc.txt   |   6 +
>  drivers/mmc/host/dw_mmc-rockchip.c                 |   8 ++
>  drivers/mmc/host/dw_mmc.c                          | 134 ++++++++++++---------
>  drivers/mmc/host/dw_mmc.h                          |   1 +
>  4 files changed, 90 insertions(+), 59 deletions(-)

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