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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.52.1 (3.52.1-1.fc40) Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Thu, 2024-06-13 at 09:39 -0500, David Lechner wrote: > On 6/13/24 9:18 AM, Krzysztof Kozlowski wrote: > > On 13/06/2024 15:57, David Lechner wrote: > > >=20 > > > >=20 > > > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 - const: = adi,ad4695 > > > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 - items: > > > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 - const: = adi,ad4697-wlcsp > > > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 - const: = adi,ad4697 > > > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 # same chips with higher max samp= le rate > > >=20 > > > I suppose one could make the argument that the programming model is > > > the same on these too, but the maximum sampling frequency does seem > > > like an important bit of information so that you don't try to set > > > the conversion trigger rate too high. > > >=20 > >=20 > > which property is that? I don't see differences in the driver, so I > > don't get how these wlcsp compatibles allow you to control value of > > conversion trigger. >=20 > This comment is unrelated to the package type (WLCSP or LFCSP). >=20 > What I mean is that e.g. AD4695 and AD4696 are virtually identical > other than the maximum allowable sample rate (500 kSPS or 1 MSPS). >=20 > So my thinking was that it would make sense to have: >=20 > compatible =3D "ad4695"; >=20 > for the lower sample rate chip and >=20 > compatible =3D "ad4696", "ad4695"; >=20 > for the higher sample rate chip since ad4696 can do everything > that ad4695 does plus a bit more. >=20 IMO, that would make sense yes. If the higher sample rate chip fallsback, i= t will still work but not at full speed. The other way around is the one that we c= an't allow naturally. But possibly dumb question now... since both devices will be supported at t= he same time, do we actually care about having the fallback compatible? My understa= nding of the fallback story is that we may load a DTS in an older kernel where chip = A is supported but chip B is not and it is ok for chip B to fallback to chip A. = Since these devices will be supported at the same time, do we need to care? Unles= s out of tree stuff enters the equation? Or is there another usecase that I'm not aware about (or maybe it just make= s sense to document properly...)? - Nuno S=C3=A1 >=20