On 30/05/2024 10:50, Nuno Sá wrote: > On Wed, 2024-05-29 at 17:04 +0100, Conor Dooley wrote: >> On Wed, May 29, 2024 at 04:38:53PM +0300, Ceclan, Dumitru wrote: >>> On 28/05/2024 20:52, Conor Dooley wrote: >>>> On Tue, May 28, 2024 at 03:16:07PM +0300, Ceclan, Dumitru wrote: >>>>> On 27/05/2024 20:48, Conor Dooley wrote: >>>>>> On Mon, May 27, 2024 at 08:02:34PM +0300, Dumitru Ceclan via B4 Relay >>>>>> wrote: >>>>>>> From: Dumitru Ceclan <dumitru.ceclan@xxxxxxxxxx> >>>>>>> + adi,channel-type: >>>>>>> + description: >>>>>>> + Used to differentiate between different channel types as the >>>>>>> device >>>>>>> + register configurations are the same for all usage types. >>>>>>> + Both pseudo-differential and single-ended channels will use >>>>>>> the >>>>>>> + single-ended specifier. >>>>>>> + $ref: /schemas/types.yaml#/definitions/string >>>>>>> + enum: >>>>>>> + - single-ended >>>>>>> + - differential >>>>>>> + default: differential >>>>>> >>>>>> I dunno if my brain just ain't workin' right today, or if this is not >>>>>> sufficiently explained, but why is this property needed? You've got >>>>>> diff-channels and single-channels already, why can you not infer the >>>>>> information you need from them? What should software do with this >>>>>> information? >>>>>> Additionally, "pseudo-differential" is not explained in this binding. >>>>> >>>>> In previous thread we arrived to the conclusion single-ended and >>>>> pseudo-differential channels should be marked with the flag >>>>> "differential=false" in the IIO channel struct. This cannot >>>>> really be inferred as any input pair could be used in that >>>>> manner and the only difference would be in external wiring. >>>>> >>>>> Single-channels cannot be used to define such a channel as >>>>> two voltage inputs need to be selected. Also, we are already >>>>> using single-channel to define the current channels. >>>> >>>> If I understand correctly, the property could be simplified to a flag >>>> then, since it's only the pseudo differential mode that you cannot be >>>> sure of? >>>> You know when you're single-ended based on single-channel, so the >>>> additional info you need is only in the pseudo-differential case. >>>> >>> Yes, it could just be a boolean flag. The only thing I have against >>> that is the awkwardness of having both diff-channels and >>> differential=false within a channel definition. >> >> What I was suggesting was more like "adi,pseudo-differential" (you don't >> need to set the =false or w/e, flag properties work based on present/not >> present). I think that would avoid the awkwardness? >> > > Yeah, that was also my understanding of your reply... But I think you're also > mentioning to have this flag together with the single-channel property? > > I'm a bit confused because it seems to me that single-channel only gets one input > while we need to select two for pseudo-differential/single-ended. Is this correct > Dumitru? > Yes, that is correct. > FWIW, I think we already have that awkwardness in the current form. If I'm not > missing anything, what we have in the driver is pretty much: > > if (not diff && single-channel) > // then current channel > else > // relies on the channel-type stuff > > So, effectively with the above we have > > diff-channels = <1 0>; > > but then wait, not so fast > This comment properly and comically describes the hot mess that I've come up with :))) > adi,channel-type = "single-ended" > > To me the above is equally awkward (not sure if there's any precedence in using diff- > channels like this though)... > > I would like for this to be explicit... If we have diff-channels, then it's surely > differential. > > If not we could use the single-channel property and instead of using an extra flag we > could make the property having either 1 or 2 items. If we have 1, then it's a current > channel. If we have 2, then it's voltage single-ended/pseudo-differential. > > David's suggestion is also pretty good (and I like it's more explicit about what's > going on) so I would likely go with it... > > - Nuno Sá > > Yup, as neat as it could be, I'll do it that way.
