Received-SPF: pass (google.com: domain of linux-kernel+bounces-202613-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223;
Message-ID: <26e9970c-7dbf-48ac-9832-58bf2952d350@bootlin.com>
Date: Wed, 5 Jun 2024 14:32:35 +0200
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH v2 1/3] dt-bindings: i2c: gpio: Add 'transition-delay-us'
 property
To: Rob Herring <robh@kernel.org>, Peter Rosin <peda@axentia.se>
Cc: Andi Shyti <andi.shyti@kernel.org>,
 Krzysztof Kozlowski <krzk+dt@kernel.org>, Conor Dooley
 <conor+dt@kernel.org>, Peter Korsgaard <peter.korsgaard@barco.com>,
 Wolfram Sang <wsa@kernel.org>, linux-i2c@vger.kernel.org,
 devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
 Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
 Herve Codina <herve.codina@bootlin.com>,
 Christopher Cordahi <christophercordahi@nanometrics.ca>
References: <20240529091739.10808-1-bastien.curutchet@bootlin.com>
 <20240529091739.10808-2-bastien.curutchet@bootlin.com>
 <718d86a7-d70a-c38a-089d-5276bcc6e88b@axentia.se>
 <20240603155810.GA509311-robh@kernel.org>
Content-Language: en-US
From: Bastien Curutchet <bastien.curutchet@bootlin.com>
In-Reply-To: <20240603155810.GA509311-robh@kernel.org>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit

Hi Rob, Hi Peter,

On 6/3/24 17:58, Rob Herring wrote:
> On Wed, May 29, 2024 at 02:13:37PM +0200, Peter Rosin wrote:
>> Hi!
>>
>> 2024-05-29 at 11:17, Bastien Curutchet wrote:
>>> I2C MUXes described by the i2c-gpio-mux sometimes need a significant
>>> amount of time to switch from a bus to another. When a new bus is
>>> selected, the first I2C transfer can fail if it occurs too early. There
>>> is no way to describe this transition delay that has to be waited before
>>> starting the first I2C transfer.
>>>
>>> Add a 'transition-delay-us' property that indicates the delay to be
>>> respected before doing the first i2c transfer.
>>
>> The io-channel-mux has a property with very similar intent named
>> settle-time-us [1]. I think we should use the same name here.
>>
>> [1] Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.yaml
> 
> Agreed. I knew we had something and went looking... I only checked the
> base mux and i2c mux bindings.
> 

Ok I'll do this in V3, thank you.

Best regards
Bastien