On 2021-10-26 23:02, Peter Rosin wrote: > > > On 2021-10-26 22:29, Rob Herring wrote: >> On Wed, Oct 13, 2021 at 04:10:02PM +0200, Horatiu Vultur wrote: >>> Add optional property 'select-delay' DT property. In case this is set >>> then a delay is added when changing mux state. The value is specified in >>> usec. >>> >>> Signed-off-by: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx> >>> --- >>> Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt | 1 + >>> 1 file changed, 1 insertion(+) >>> >>> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt >>> index d4cf10582a26..d0dacbad491a 100644 >>> --- a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt >>> +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt >>> @@ -28,6 +28,7 @@ Required properties: >>> Optional properties: >>> - idle-state: value to set the muxer to when idle. When no value is >>> given, it defaults to the last value used. >>> +- select-delay: GPIO settle delay when changing mux state. In usec. >> >> Seems generally useful. Can we add this first to the mux control >> binding, then use it here (or better yet, use the mux binding if you >> can instead). > > It is actually not very useful here, nor in the mux-control binding. The > same gpio lines (or mux-control) could be used to control several muxes, > all with vastly different needs as to how long the settle time needs to > be. I.e. it is not the gpio lines (or mux-control) that need to settle, > it is the signal(s) that travel through the controlled mux(es) that need > to settle. > > In this case, a settle time property was added to the io-channel-mux > binding, which makes much more sense. > > https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git/commit/Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.yaml?h=char-misc-next&id=b9221f71c285 Oh crap, sorry. This series went right past me since it somehow didn't get flagged in my inbox. But Robs answer did, and then I assumed it was a late answer to this series: https://lore.kernel.org/lkml/20211004153640.20650-1-vincent.whitchurch@xxxxxxxx/ Which it of course isn't. But in my mind it was. Result: my above response does not make any sense. I'll have to go to bed now, but I promise to write a proper answer tomorrow. Cheers, Peter > Cheers, > Peter > >> Also, properties with units need a standard unit suffix. >> >>> >>> For each i2c child node, an I2C child bus will be created. They will >>> be numbered based on their order in the device tree. >>> -- >>> 2.33.0 >>> >>>