RE: [PATCH v2 01/11] dt-bindings: mmc: arasan: Update documentation for SD Card Clock
From: Manish Narani
Date: Tue Jul 23 2019 - 04:23:32 EST
Thanks a lot for the review!
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> Subject: Re: [PATCH v2 01/11] dt-bindings: mmc: arasan: Update
> documentation for SD Card Clock
> On Mon, Jul 01, 2019 at 10:59:41AM +0530, Manish Narani wrote:
> > The clock handling is to be updated in the Arasan SDHCI. As the
> > 'devm_clk_register' is deprecated in the clock framework, this needs to
> > specify one more clock named 'clk_sdcard' to get the clock in the driver
> > via 'devm_clk_get()'. This clock represents the clock from controller to
> > the card.
> Please explain why in terms of the binding, not some driver calls.
> > Signed-off-by: Manish Narani <manish.narani@xxxxxxxxxx>
> > ---
> > Documentation/devicetree/bindings/mmc/arasan,sdhci.txt | 15 ++++++++++-
> > 1 file changed, 10 insertions(+), 5 deletions(-)
> > diff --git a/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
> > index 1edbb04..15c6397 100644
> > --- a/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
> > +++ b/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
> > @@ -23,6 +23,10 @@ Required Properties:
> > - reg: From mmc bindings: Register location and length.
> > - clocks: From clock bindings: Handles to clock inputs.
> > - clock-names: From clock bindings: Tuple including "clk_xin" and "clk_ahb"
> > + Apart from these two there is one more optional clock which
> > + is "clk_sdcard". This clock represents output clock from
> > + controller and card. This must be specified when #clock-cells
> > + is specified.
> > - interrupts: Interrupt specifier
> > Required Properties for "arasan,sdhci-5.1":
> > @@ -36,9 +40,10 @@ Optional Properties:
> > - clock-output-names: If specified, this will be the name of the card clock
> > which will be exposed by this device. Required if #clock-cells is
> > specified.
> > - - #clock-cells: If specified this should be the value <0>. With this property
> > - in place we will export a clock representing the Card Clock. This clock
> > - is expected to be consumed by our PHY. You must also specify
> > + - #clock-cells: If specified this should be the value <0>. With this
> > + property in place we will export one clock representing the Card
> > + Clock. This clock is expected to be consumed by our PHY. You must also
> > + specify
> specify what?
I think this line was already there, I missed to correct it, Will update in v3.
> The 3rd clock input I assume? This statement means any existing users
> with 2 clock inputs and #clock-cells are in error now. Is that correct?
Yes, this is correct. So far there was only one vendor using '#clock-cells' which is Rockchip. I have sent DT patch (02/11) for that also.
Here this is needed as earlier implementation isn't correct as suggested by Uffe. (https://lkml.org/lkml/2019/6/20/486) .