Re: [PATCH v2 4/5] ARM: dts: omap5: describe control for ckobuffer

From: H. Nikolaus Schaller
Date: Wed Apr 27 2016 - 02:05:15 EST



> Am 26.04.2016 um 19:27 schrieb Tony Lindgren <tony@xxxxxxxxxxx>:
>
> Tero,
>
> * H. Nikolaus Schaller <hns@xxxxxxxxxxxxx> [160418 11:23]:
>> OMAP5 has a register to control if the ckobuffer is enabled
>> and defines the polarity. ckobuffer is required to drive a twl6040
>> with the system clock. Hence, add the pinctrl,single to the
>> OMAP5 SoC description so that omap5-board-common can
>> set up the ckobuffer as required.
>
> Is this really a mux or should it be a mux clock?

It is a pinmux setting for the clock out buffer to choose what signal
(and polarity) is presented on the fref_xtal_clk pad.

The register is part of the CTRL_MODULE_WKUP.
The clock signal is the xtal master clock of the whole SoC.

Although there is a bit to choose an alternate clock, there is no
alternate in the OMAP5 silicon.

Therefore I would say it is about padconf and not clock or clock mux
related.

It just happens to be a clock signal which can be routed to this
pad.

BR,
Nikolaus

>
> Regards,
>
> Tony
>
>> Signed-off-by: H. Nikolaus Schaller <hns@xxxxxxxxxxxxx>
>> ---
>> arch/arm/boot/dts/omap5.dtsi | 10 ++++++++++
>> 1 file changed, 10 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/omap5.dtsi b/arch/arm/boot/dts/omap5.dtsi
>> index 120b6b8..1d9050f 100644
>> --- a/arch/arm/boot/dts/omap5.dtsi
>> +++ b/arch/arm/boot/dts/omap5.dtsi
>> @@ -277,6 +277,16 @@
>> pinctrl-single,register-width = <16>;
>> pinctrl-single,function-mask = <0x7fff>;
>> };
>> +
>> + omap5_control_ckobuffer: pinmux@cdb4 {
>> + compatible = "ti,omap5-padconf",
>> + "pinctrl-single";
>> + reg = <0xcdb4 4>;
>> + #address-cells = <1>;
>> + #size-cells = <0>;
>> + pinctrl-single,register-width = <32>;
>> + pinctrl-single,function-mask = <0xf0000000>;
>> + };
>> };
>>
>> ocmcram: ocmcram@40300000 {
>> --
>> 2.7.3
>>