Re: [PATCH v2 3/6] clk: ti: dra7: Add clkctrl clock data for the mcan clocks

From: Tony Lindgren
Date: Fri Jun 01 2018 - 10:26:25 EST


* Faiz Abbas <faiz_abbas@xxxxxx> [180601 06:49]:
> Hi,
>
> On Thursday 31 May 2018 06:59 PM, Tero Kristo wrote:
> > On 31/05/18 13:14, Faiz Abbas wrote:
> >> Hi,
> >>
> >> On Thursday 31 May 2018 09:33 AM, Rob Herring wrote:
> >>> On Wed, May 30, 2018 at 07:41:30PM +0530, Faiz Abbas wrote:
> >>>> Add clkctrl data for the m_can clocks and register it within the
> >> ...
> >>>> Â diff --git a/include/dt-bindings/clock/dra7.h
> >>>> b/include/dt-bindings/clock/dra7.h
> >>>> index 5e1061b15aed..d7549c57cac3 100644
> >>>> --- a/include/dt-bindings/clock/dra7.h
> >>>> +++ b/include/dt-bindings/clock/dra7.h
> >>>> @@ -168,5 +168,6 @@
> >>>> Â #define DRA7_COUNTER_32K_CLKCTRLÂÂÂ DRA7_CLKCTRL_INDEX(0x50)
> >>>> Â #define DRA7_UART10_CLKCTRLÂÂÂ DRA7_CLKCTRL_INDEX(0x80)
> >>>> Â #define DRA7_DCAN1_CLKCTRLÂÂÂ DRA7_CLKCTRL_INDEX(0x88)
> >>>> +#define DRA7_ADC_CLKCTRLÂÂÂ DRA7_CLKCTRL_INDEX(0xa0)
> >>>
> >>> ADC and mcan are the same thing?
> >>>
> >>
> >> The register to control MCAN clocks is called ADC_CLKCTRL, Yes.
> >
> > Is there any reason for this or is that just a documentation bug?
> >
>
> Looks like they meant to have an ADC in dra74 or dra72 but decided
> against it and then many years later used the same registers for MCAN
> instead. You can see ADC_CLKCTRL exists in dra72 TRM but is explicitly
> disabled.
>
> http://www.ti.com/lit/ug/spruic2b/spruic2b.pdf pg:1524

How about make add also something like to dra7.h:

#define DRA7_MCAN_CLKCTRL DRA7_ADC_CLKCTRL

And you can add a comment to the dts file to avoid people
getting confused with this constantly.

Regards,

Tony