linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: Wolfram Sang <wsa@the-dreams.de>
To: Laine Jaakko EXT <ext-jaakko.laine@vaisala.com>,
	Rob Herring <robh@kernel.org>
Cc: devicetree@vger.kernel.org,
	"michal.simek@xilinx.com" <michal.simek@xilinx.com>,
	Shubhrajyoti Datta <shubhrajyoti.datta@gmail.com>,
	"linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>,
	"linux-i2c@vger.kernel.org" <linux-i2c@vger.kernel.org>
Subject: Re: [PATCH] i2c: xiic: Support disabling multi-master in DT
Date: Thu, 2 Apr 2020 11:28:13 +0200	[thread overview]
Message-ID: <20200402092813.GA986@ninjato> (raw)
In-Reply-To: <AM0PR06MB5185F8F51316FCD5213F0ABED4C60@AM0PR06MB5185.eurprd06.prod.outlook.com>


[-- Attachment #1.1: Type: text/plain, Size: 1471 bytes --]

Hi Jaako,

> > My best bet is to introduce another binding "single-master" which says
> > clearly that we are the only bus master on that bus.
> >
> > Both bindings missing means then "unclear".
> >
> > I think this matches reality best.
> >
> > Opinions?

> I agree that this sounds like the best option if original binding
> can't be used, even though it can also be a bit confusing to have 2
> similar bindings.

I think it becomes understandable if we emphasize that "no bindings"
means "unclear". We need to document it.

> How would both bindings existing simultaneously be interpreted? Maybe
> both existing simultaneously should be considered as an invalid
> configuration, so that it would be enough to just check the one you
> need? The other option would be to treat both existing similarly to
> neither existing, which would require the driver to always check both
> if checking one.

I am clearly for saying that this is an illegal combination. I'd hope
this can be expressed in a YAML binding. Yet, my research didn't give me
an answer. Adding Rob and DT list to CC. Question is:

Can we check if the boolean bindings "multi-master" and "single-master"
are not applied at the same time? Any other combination is okay, i.e.
just one of them or none of them.

> Should the new single-master binding also be a general binding for all
> I2C drivers or a binding just defined for the XIIC driver? Having it

It should definately be global.

Thanks,

   Wolfram


[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

[-- Attachment #2: Type: text/plain, Size: 176 bytes --]

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2020-04-02  9:28 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-18 13:58 [PATCH] i2c: xiic: Support disabling multi-master in DT Laine Jaakko EXT
2020-02-24 10:13 ` Michal Simek
2020-02-25 14:08   ` Laine Jaakko EXT
2020-02-25 14:13     ` Wolfram Sang
2020-02-25 14:27       ` Laine Jaakko EXT
2020-02-25 14:32         ` Wolfram Sang
2020-02-25 14:37           ` Michal Simek
2020-02-25 14:41             ` Wolfram Sang
2020-02-25 14:44               ` Michal Simek
2020-02-25 14:48                 ` Wolfram Sang
2020-02-25 14:49                   ` Michal Simek
2020-03-18 12:20 ` Shubhrajyoti Datta
2020-03-18 16:49   ` Laine Jaakko EXT
2020-03-19  9:34     ` Shubhrajyoti Datta
2020-03-19 10:26       ` Laine Jaakko EXT
2020-04-16 10:42         ` Laine Jaakko EXT
2020-04-01 14:41     ` Wolfram Sang
2020-04-02  6:16       ` Laine Jaakko EXT
2020-04-02  9:28         ` Wolfram Sang [this message]
2020-05-04 12:58           ` Laine Jaakko EXT
2020-05-27 11:07             ` Wolfram Sang
2020-05-27 11:27               ` Laine Jaakko EXT

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=20200402092813.GA986@ninjato \
    --to=wsa@the-dreams.de \
    --cc=devicetree@vger.kernel.org \
    --cc=ext-jaakko.laine@vaisala.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-i2c@vger.kernel.org \
    --cc=michal.simek@xilinx.com \
    --cc=robh@kernel.org \
    --cc=shubhrajyoti.datta@gmail.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).