Re: [PATCH v3 2/2] dt-bindings: net: bluetooth: Add device tree bindings for QTI chip wcn3998

From: c-hbandi
Date: Mon Mar 25 2019 - 07:30:39 EST


Hi Matthias,

On 2019-03-15 00:26, Matthias Kaehlcke wrote:
Hi Harish,

On Wed, Mar 13, 2019 at 12:00:06PM +0530, c-hbandi@xxxxxxxxxxxxxx wrote:
Hi Matthias,


On 2019-03-12 22:29, Matthias Kaehlcke wrote:
> +DT folks
>
> Please add them in future versions (script/scripts/get_maintainer.pl
> <patches> should have listed them)

[Harish] -- Will add them in new version of patches.
>
> On Tue, Mar 12, 2019 at 05:52:59PM +0530, Harish Bandi wrote:
> > This patch enables regulators for the Qualcomm Bluetooth wcn3998
> > controller.
>
> No, it doesn't.
>
> The next version should probably say something like "Add compatible
> string for the Qualcomm WCN3998 Bluetooth controller.
>
[Harish] -- From new patch onwards will add all patch
version changes and add proper description.

> Is there any particular reason why QCA drivers folks use 'wcn' instead
> of 'WCN'? The QCA documentations calls it WCN399x, so I'd suggest to
> consistently use the uppercase name in comments and documentation (and
> log messages?).
>
[Harish] -- I think in DT we need to have small case like wcn,

agreed

i think that is the reason it started using in code, comments and dt
documentation.

AFAIK there are no hard rules for everything, my suggestion would be:

- use WCN399x
- for general comments/documentation
- commit messages
- in DT context wcn3998-n seems ok
- use wcn399x
- for function and variable names
- for compatible strings

For logging: whatever, just be consistent.

[Harish] --For Commit messages and all will try to follow change it new patch


> > Signed-off-by: Harish Bandi <c-hbandi@xxxxxxxxxxxxxx>
> > ---
> > changes in v3:
> > - updated to latest code base.
>
> This comment is useless, please describe what changed wrt the previous
> version.
[Harish] -- added details in v2, and v3 uploaded just to rebase on tip of
bluetooth-next
for better understanding of code in review. From new patch onwards will add
all patch
version changes and add proper description.
>
> > ---
> > .../devicetree/bindings/net/qualcomm-bluetooth.txt | 15
> > +++++++++++++++
> > 1 file changed, 15 insertions(+)
> >
> > diff --git
> > a/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt
> > b/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt
> > index 824c0e2..1221535 100644
> > --- a/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt
> > +++ b/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt
> > @@ -53,3 +53,18 @@ serial@898000 {
> > max-speed = <3200000>;
> > };
> > };
> > +
> > +&blsp1_uart3 {
> > + pinctrl-names = "default";
> > + pinctrl-0 = <&blsp1_uart3_default>;
> > + status = "okay";
> > +
> > + bluetooth: wcn3998-bt {
> > + compatible = "qcom,wcn3998-bt";
> > + vddio-supply = <&vreg_l6_1p8>;
> > + vddxo-supply = <&vreg_l5_1p8>;
> > + vddrf-supply = <&vreg_s5_1p35>;
> > + vddch0-supply = <&vdd_ch0_3p3>;
> > + max-speed = <3200000>;
> > + };
> > +};
> > \ No newline at end of file
>
> I think the example isn't really needed since it's essentially the
> same as the one for 'qcom,wcn3990-bt'.
>
> But the important part is missing: add the new compatible string under
> ÂRequired propertiesÂ. You also want to update the documentation that
> mentiones 'qcom,wcn3990-bt' to 'qcom,wcn399x-bt' (assuming for now
> that other possible WCN399x chips would be similar).
>
[Harish] -- Will check the DT properties, documentation and update
accordingly in new patch.

> You mentioned in an earlier version of the series that there are
> multiple WCN3998 variants with different requirements for
> voltage/current. This seems to suggests that multiple compatible
> strings are needed to distinguish between them.
>
[Harish] -- for now we want to add WCN3998 support only, What i mean to say
in my earlier
explanation that. WCN3990 is base variant and on top of that we have
variants like WCN3990,
WCN3998 and WCN3998-0,WCN3998-1 like that..
So I think wcn399x would make sense for this series.

If the variants have relevant differences between them (like different
regulator requirements) I think you want unique names, rather than
'wcn399x' (I was referring to comments/documentation with this
string).

If there are variants wouldn't your first 'wcn3998' already be a
'wcn3998-n'? If 'wcn3998' without suffix is used I think it needs to
be valid for all 'wcn3998-n' variants (it might be less
power-efficient though than using the variant specific compatible
string), otherwise things get confusing (a 'wcn3998-2' isn't a
'wcn3998'?)



[Harish] -- for now WCN3990 and WCN3998 only, also wcn3998-2 and wcn3998 are same.
So for now we are going to have only WCN3990 and WCN3998 for DT.


Thanks

Matthias