diff mbox series

[1/3] dt-bindings: i2c: gpio: Add 'transition-delay-ms' property

Message ID 20240527113908.127893-2-bastien.curutchet@bootlin.com
State Superseded
Headers show
Series i2c: mux: gpio: Add 'transition-delay-ms' property | expand

Commit Message

Bastien Curutchet May 27, 2024, 11:39 a.m. UTC
The i2c-gpio-mux can be used to describe a multiplexer built upon
several i2c isolators having an enable pin (such as LTC4310). These
isolators can need some time between their enable pin's assertion and
the first i2c transfer.

Add a 'transition-delay-ms' property that indicates the delay to be
respected before doing the first i2c transfer.

Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com>
---
 Documentation/devicetree/bindings/i2c/i2c-mux-gpio.yaml | 3 +++
 1 file changed, 3 insertions(+)

Comments

Krzysztof Kozlowski May 27, 2024, 2:38 p.m. UTC | #1
On 27/05/2024 13:39, Bastien Curutchet wrote:
> The i2c-gpio-mux can be used to describe a multiplexer built upon
> several i2c isolators having an enable pin (such as LTC4310). These
> isolators can need some time between their enable pin's assertion and
> the first i2c transfer.
> 
> Add a 'transition-delay-ms' property that indicates the delay to be
> respected before doing the first i2c transfer.
> 

That's quite limited hardware description, comparing to cover letter.
Please provide full description here, not in cover letter. This is the
binding, so the hardware part.

Anyway, this does not look like property of mux itself. If there is no
isolator, the mux would work fine, right?

Then why you are not adding this property to every possible bus and I2C
controller? I2C isolator could be placed there as well.

So just like RC binding, that's not a property of I2C mux. Maybe this
fits usage of GPIO RC / delay binding.

Best regards,
Krzysztof
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.yaml
index f34cc7ad5a00..5bca58b78359 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.yaml
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.yaml
@@ -57,6 +57,9 @@  properties:
       last value used.
     $ref: /schemas/types.yaml#/definitions/uint32
 
+  transition-delay-ms:
+    description: Delay to wait before doing any transfer when a new bus gets selected.
+
 allOf:
   - $ref: i2c-mux.yaml