From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B982C49251B; Tue, 5 May 2026 17:10:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778001000; cv=none; b=i0hbeRmy0v9l+TQOgg5fbOYleIdLP5hOjMg3RqPWP3hZRFBckCC1LtSxiEuJV8An9F+wIkD/ICPUwaAy6OsRYsbENKLx2SN9g9Y9sPKrt+QgoDmrVidMs9wK4Q2IaLU9vyj5x76YaLvskxc0olWokJb8RXzYiXXxcvcHXjLcVa4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778001000; c=relaxed/simple; bh=mKF9MtJdN12/ezpzx+6Gx5YWYtCRGx7bFBhDIXAgUeM=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Dzroud2Q+m0PBowkYMDqakNhS3VqGxdi5HykgaCbxmlRSphPe2x6jQNCw4WmkS4be5GYd8trh4Uk6H9W3QDJdRw8bc+e3QAJbpqUw6wNzzrFRX9C80Zkr1xO0nuAMStG8hsvLSst7ySXgCCaFlGvMXbAYDcsw+1KggjcgF7nGu8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZvMEyuJx; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ZvMEyuJx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CCB76C2BCB4; Tue, 5 May 2026 17:09:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778001000; bh=mKF9MtJdN12/ezpzx+6Gx5YWYtCRGx7bFBhDIXAgUeM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=ZvMEyuJxqN+rnB59LG4kVV4VCnbnBl4VHFjoMk3Dy6XT89qT0WsgMpc/qQ7wTEexd tlX6lFjwXM/CiIE5oOl/O6LyWd0QcFClGvihxofpyhVztY/mpa8mMte71rmFpYbV0o GF5F+QXLWNqNQvEwdv6JlrbKSZ57jpCECc9qsrMRiOwVfkZmVLAFNY+TTAuqDFE3bz hYCXC5Of3jdZxhYdxf4VyOSeqt+RpWsWp5aZ+H3D1ShBMz4SFjG+DpE1fPxFnM2FQA eiTLA4d4rvnyybyck/+LaC6qkqOetG6jk/G9lWIuWHUWRKSydKMpf9VoaYdIJKbZHB 9dNozsSodBrvQ== Date: Tue, 5 May 2026 18:09:47 +0100 From: Jonathan Cameron To: Rodrigo Alencar <455.rodrigo.alencar@gmail.com> Cc: Nuno =?UTF-8?B?U8Oh?= , Rodrigo Alencar via B4 Relay , rodrigo.alencar@analog.com, linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-hardening@vger.kernel.org, Lars-Peter Clausen , Michael Hennerich , David Lechner , Andy Shevchenko , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Philipp Zabel , Jonathan Corbet , Shuah Khan , Kees Cook , "Gustavo A. R. Silva" Subject: Re: [PATCH RFC v3 9/9] docs: iio: add documentation for ad9910 driver Message-ID: <20260505180947.4792eb25@jic23-huawei> In-Reply-To: References: <20260417-ad9910-iio-driver-v3-0-29b93712a228@analog.com> <20260417-ad9910-iio-driver-v3-9-29b93712a228@analog.com> <20260426141007.345c76e4@jic23-huawei> <20260427104608.7819a134@jic23-huawei> X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Mon, 27 Apr 2026 15:54:14 +0100 Rodrigo Alencar <455.rodrigo.alencar@gmail.com> wrote: > On 26/04/27 11:31AM, Nuno S=C3=A1 wrote: > > On Mon, Apr 27, 2026 at 10:46:08AM +0100, Jonathan Cameron wrote: =20 > > > On Sun, 26 Apr 2026 21:42:15 +0100 > > > Rodrigo Alencar <455.rodrigo.alencar@gmail.com> wrote: > > > =20 > > > > On 26/04/26 02:10PM, Jonathan Cameron wrote: =20 > > > > > On Fri, 17 Apr 2026 09:17:38 +0100 > > > > > Rodrigo Alencar via B4 Relay wrote: > > > > > =20 > > > > > > From: Rodrigo Alencar > > > > > >=20 > > > > > > Add documentation for the AD9910 DDS IIO driver, which describe= s channels, > > > > > > DDS modes, attributes and ABI usage examples. > > > > > >=20 > > > > > > Signed-off-by: Rodrigo Alencar = =20 > > > > >=20 > > > > > Hi Rodrigo, > > > > >=20 > > > > > I think this is getting close to something workable subject to so= me tweaks > > > > > to not make the priority thing visible and use rate of change par= ameters > > > > > so /Sec rather than steps. =20 > > > >=20 > > > > I am not sure about this one. Getting the value into units per seco= nds will > > > > increase the range of values by a lot, e.g., for the frequency case= the step > > > > size can range from a few Hz up to the entire supported range (hund= reds of > > > > MHz), and if you consider that one would often have the sampling_fr= equency > > > > at 250 MHz... an attribute frequency_roc could have an order of 10^= 17 Hz/s, > > > > and I am not sure how practical is that, although it can have a phy= sical meaning, > > > > like a "chirp slope". =20 > > >=20 > > > That scaling is indeed a bit of a pain though it will go in a 64 bit = int > > > however, seems likely we'll get higher frequency devices one day that= will > > > limb even faster. > > >=20 > > > Maybe wait and see if anyone else has input on this. =20 > >=20 > > If we think things like RF DACs (which internally - typically - make use > > of things like DDS), we can already go to the GHz "world". > >=20 > > Not saying we already have such a device that would map the new ABI with > > bigger values (we might have but nothing I'm aware of from the top of my > > head) but just saying the above is, indeed, very likely to pop up at so= me > > time. > >=20 > > Just something to bear in mind :) > >=20 > > - Nuno S=C3=A1 =20 >=20 > under this Documentation/ABI/testing/sysfs-bus-iio-impedance-analyzer-ad5= 933, > there is ABI: /sys/bus/iio/devices/iio:deviceX/out_altvoltageY_frequency_= increment >=20 > which seems to be a similar concept to the step used here. Yeah but staging driver so let's not focus on that too much. >=20