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Wed, 14 Jan 2026 05:31:37 -0800 (PST) Message-ID: <0ad12e16e3fffb4b72a460d7f2b2e627a781b93b.camel@gmail.com> Subject: Re: [PATCH v3 0/4] iio: adc: ad9467: Support alternative backends From: Nuno =?ISO-8859-1?Q?S=E1?= To: Tomas Melin , Michael Hennerich , Nuno Sa , Lars-Peter Clausen , Jonathan Cameron , David Lechner , Andy Shevchenko , Olivier Moysan Cc: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Date: Wed, 14 Jan 2026 13:32:19 +0000 In-Reply-To: <20260114-b4-ad9467-optional-backend-v3-0-d2c84979d010@vaisala.com> References: <20260114-b4-ad9467-optional-backend-v3-0-d2c84979d010@vaisala.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.2 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Wed, 2026-01-14 at 10:45 +0000, Tomas Melin wrote: > To facilitate backends with different set of features, add support > for defining capabilites provided by the backend. These capabilites > typically extend beyond a single operation and are therefore not > directly linked to if a single function call is implemented or not. > Furthermore, the capabilites determine if a certain set of operations > should be attempted, or skipped by the frontend. This way > the frontend driver can work with a minimalistic set of features and > still have the device in fully functional state. >=20 > Signed-off-by: Tomas Melin > --- Hi Tomas, > Changes in v3: > - Reduce set of capabilities to only include calibration. The other > =C2=A0 ones propsed in V2 can be seen as subset of calibration, or single > =C2=A0 operation failing with opnotsupported As stated in my patch comment. Using opnotsupported for buffers defeats the CAPS idea. But more importantly, how are your usecase supposed to work with this series? I'm not seeing any new backend being added as part of the series. Point is, if we are adding all of this, I would expect your usecase to have fully upstream support. If I'm not missing nothing, we would at least need a dummy backend providing stubs for enable()/disable() - Nuno S=C3=A1