From: Conor Dooley <conor@kernel.org>
To: Peter Rosin <peda@lysator.liu.se>
Cc: Shiv Prakash Gupta <shivprakash.gupta@nxp.com>,
andi.shyti@kernel.org, robh@kernel.org, krzk+dt@kernel.org,
conor+dt@kernel.org, linux-i2c@vger.kernel.org,
devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
vikash.bansal@nxp.com, priyanka.jain@nxp.com
Subject: Re: [PATCH 1/2] dt-bindings: i2c: Add NXP PCA9641 I2C bus master arbiter
Date: Wed, 9 Sep 2026 11:00:31 +0100 [thread overview]
Message-ID: <aqEuPBNsbdGZ1MJX@squawk> (raw)
In-Reply-To: <aqDt0uC7FNRmsv9S@gryt>
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On Wed, Sep 09, 2026 at 07:25:38AM +0200, Peter Rosin wrote:
> Den Tue, Sep 08, 2026 at 06:47:01PM +0100, skrev Conor Dooley:
> > On Tue, Sep 08, 2026 at 06:01:45PM +0530, Shiv Prakash Gupta wrote:
> > > Add device tree binding schema for the NXP PCA9641 2-to-1 I2C bus
> > > master arbiter.
> > >
> > > The PCA9641 arbitrates between two upstream I2C masters competing for a
> > > single downstream slave bus using a lock/grant ownership model. The
> > > binding supports an optional 'interrupts' property for interrupt-assisted
> > > arbitration.
> > >
> > > Signed-off-by: Shiv Prakash Gupta <shivprakash.gupta@nxp.com>
> > > ---
>
> ...
>
> > > + i2c-arb:
> > > + type: object
> > > + $ref: /schemas/i2c/i2c-controller.yaml
> > > + unevaluatedProperties: false
> > > + description:
> > > + I2C bus node representing the downstream slave bus controlled by the
> > > + PCA9641. Downstream slave devices are declared as child nodes here.
> >
> > Why does this node need to exist? Can't the i2c-arbiter node itself
> > contain the child devices?
>
> For symmetry with the pre-existing I2C arbs, which all have the extra
> node for historical implementation reasons? I don't know if that's
> considered a valid reason? I prefer to have all arbs follow the same
> structure...
If this is just how these devices are described in general, I think
that's probably fine.
Acked-by: Conor Dooley <conor.dooley@microchip.com>
pw-bot: not-applicable
(Also, good to see you back active)
Cheers.,
Conor.
>
> The "documentation" describing common I2C arbitration details went missing
> here:
>
> https://lore.kernel.org/all/20230731163833.319258-1-krzysztof.kozlowski@linaro.org/
>
> Cheers,
> Peter
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next prev parent reply other threads:[~2026-09-09 10:00 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-08 12:31 [PATCH 0/2] i2c: mux: Add NXP PCA9641 I2C bus master arbiter Shiv Prakash Gupta
2026-09-08 12:31 ` [PATCH 1/2] dt-bindings: i2c: " Shiv Prakash Gupta
2026-09-08 12:48 ` sashiko-bot
2026-09-08 17:47 ` Conor Dooley
2026-09-09 5:25 ` Peter Rosin
2026-09-09 10:00 ` Conor Dooley [this message]
2026-09-08 12:31 ` [PATCH 2/2] i2c: mux: Add NXP PCA9641 I2C bus master arbiter driver Shiv Prakash Gupta
2026-09-08 12:52 ` sashiko-bot
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