| Message ID | 20240529091739.10808-2-bastien.curutchet@bootlin.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | i2c: mux: gpio: Add 'transition-delay-us' property | expand |
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. Rob
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.yaml index f34cc7ad5a00..20d72c3e1e10 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-us: + description: Delay to wait before doing any transfer when a new bus gets selected. + allOf: - $ref: i2c-mux.yaml
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. Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com> --- Documentation/devicetree/bindings/i2c/i2c-mux-gpio.yaml | 3 +++ 1 file changed, 3 insertions(+)