From: Conor Dooley <conor.dooley@microchip.com>
To: Guo Samin <samin.guo@starfivetech.com>
Cc: Andrew Lunn <andrew@lunn.ch>, Conor Dooley <conor@kernel.org>,
<linux-kernel@vger.kernel.org>, <devicetree@vger.kernel.org>,
<netdev@vger.kernel.org>, Peter Geis <pgwipeout@gmail.com>,
Frank <Frank.Sae@motor-comm.com>,
"David S . Miller" <davem@davemloft.net>,
Eric Dumazet <edumazet@google.com>,
Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
Rob Herring <robh+dt@kernel.org>,
Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
Heiner Kallweit <hkallweit1@gmail.com>,
Russell King <linux@armlinux.org.uk>,
Yanhong Wang <yanhong.wang@starfivetech.com>
Subject: Re: [PATCH v3 1/2] dt-bindings: net: motorcomm: Add pad driver strength cfg
Date: Tue, 20 Jun 2023 09:26:57 +0100 [thread overview]
Message-ID: <20230620-clicker-antivirus-99e24a06954e@wendy> (raw)
In-Reply-To: <15eb4ffe-ea12-9a2c-ae9d-c34860384b60@starfivetech.com>
[-- Attachment #1: Type: text/plain, Size: 3111 bytes --]
Hey,
On Tue, Jun 20, 2023 at 11:09:52AM +0800, Guo Samin wrote:
> From: Guo Samin <samin.guo@starfivetech.com>
> > From: Conor Dooley <conor@kernel.org>
> >> On Fri, May 26, 2023 at 05:05:01PM +0800, Samin Guo wrote:
> >>> The motorcomm phy (YT8531) supports the ability to adjust the drive
> >>> strength of the rx_clk/rx_data, the value range of pad driver
> >>> strength is 0 to 7.
> >>> + motorcomm,rx-clk-driver-strength:
> >>> + description: drive strength of rx_clk pad.
> >>> + $ref: /schemas/types.yaml#/definitions/uint32
> >>> + enum: [ 0, 1, 2, 3, 4, 5, 6, 7 ]
> >>
> >> I think you should use minimum & maximum instead of these listed out
> >> enums.
> > You have also had this comment since v1 & were reminded of it on
> >> v2 by Krzysztof: "What do the numbers mean? What are the units? mA?"
> > The good news is that we just got some data about units from Motorcomm.
> > Maybe I can post the data show of the unit later after I get the complete data.
> Sorry, haven't updated in a while.
NW chief.
> I just got the detailed data of Driver Strength(DS) from Motorcomm , which applies to both rx_clk and rx_data.
>
> |----------------------|
> | ds map table |
> |----------------------|
> | DS(3b) | Current (mA)|
> |--------|-------------|
> | 000 | 1.20 |
> | 001 | 2.10 |
> | 010 | 2.70 |
> | 011 | 2.91 |
> | 100 | 3.11 |
> | 101 | 3.60 |
> | 110 | 3.97 |
> | 111 | 4.35 |
> |--------|-------------|
>
> Since these currents are not integer values and have no regularity,
> it is not very good to use in the drive/dts in my opinion.
Who says you have to use mA? What about uA?
> Therefore, I tend to continue to use DS(0-7) in dts/driver, and adding
> a description of the current value corresponding to DS in dt-bindings.
I think this goes against not putting register values into the dts &
that the accurate description of the hardware are the currents.
> Like This:
>
> + motorcomm,rx-clk-driver-strength:
> + description: drive strength of rx_clk pad.
You need "description: |" to preserve the formatting if you add tables,
but I don't think that this is a good idea. Put the values in here that
describe the hardware (IOW the currents) and then you don't need to have
this table.
> + |----------------------|
> + | rx_clk ds map table |
> + |----------------------|
> + | DS(3b) | Current (mA)|
> + | 000 | 1.20 |
> + | 001 | 2.10 |
> + | 010 | 2.70 |
> + | 011 | 2.91 |
> + | 100 | 3.11 |
> + | 101 | 3.60 |
> + | 110 | 3.97 |
> + | 111 | 4.35 |
> + |--------|-------------|
> + $ref: /schemas/types.yaml#/definitions/uint32
> + enum: [ 0, 1, 2, 3, 4, 5, 6, 7 ]
> + default: 3
> +
> Or use minimum & maximum instead of these listed out enums
With the actual current values, enum rather than min + max.
Cheers,
Conor.
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]
next prev parent reply other threads:[~2023-06-20 8:27 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-26 9:05 [PATCH v3 0/2] Add motorcomm phy pad-driver-strength-cfg support Samin Guo
2023-05-26 9:05 ` [PATCH v3 1/2] dt-bindings: net: motorcomm: Add pad driver strength cfg Samin Guo
2023-05-26 19:41 ` Conor Dooley
2023-05-29 3:46 ` Guo Samin
2023-06-20 3:09 ` Guo Samin
2023-06-20 8:26 ` Conor Dooley [this message]
2023-06-20 8:55 ` Krzysztof Kozlowski
2023-06-21 3:03 ` Guo Samin
2023-06-20 13:29 ` Andrew Lunn
2023-06-21 3:28 ` Guo Samin
2023-06-21 14:13 ` Andrew Lunn
2023-05-26 9:05 ` [PATCH v3 2/2] net: phy: motorcomm: Add pad drive strength cfg support Samin Guo
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230620-clicker-antivirus-99e24a06954e@wendy \
--to=conor.dooley@microchip.com \
--cc=Frank.Sae@motor-comm.com \
--cc=andrew@lunn.ch \
--cc=conor@kernel.org \
--cc=davem@davemloft.net \
--cc=devicetree@vger.kernel.org \
--cc=edumazet@google.com \
--cc=hkallweit1@gmail.com \
--cc=krzysztof.kozlowski+dt@linaro.org \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=pgwipeout@gmail.com \
--cc=robh+dt@kernel.org \
--cc=samin.guo@starfivetech.com \
--cc=yanhong.wang@starfivetech.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).