From patchwork Tue Nov 21 10:20:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Nuno Sa via B4 Relay X-Patchwork-Id: 13462745 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 8F8E23C094; Tue, 21 Nov 2023 10:17:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LXnuTG5n" Received: by smtp.kernel.org (Postfix) with ESMTPS id 1E5F6C433C7; Tue, 21 Nov 2023 10:17:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1700561839; bh=3Txu7PPyn6wb+lD0p7YfYmDJ0VmWJYBmGnKE5mN5Uvg=; h=From:Subject:Date:To:Cc:Reply-To:From; b=LXnuTG5n7NZmqLVz/xbnVhEDlUMwDubNfJp5fyxB9a0RMHcFKPiOwzksJlHKCHMqu /n/85LoOR/alm7hNAS+2zkPBzWm0zNKaYkUn8LcZbH8HZNoHjkTBwTkdMFwaKBvghu 3Mgjnrlwl1a+d+8ZvQzvARKEf3paWHtn/zjAOLipA2tp7UplpT8SFdz9xdhHCzCwM2 MKt+muGsgPbElglzoi6dfEJvV3S8wKrG43lA1iceWUs+OoVwaPqBAhTNADFPRyQEMX nSV2MzA1+d6na95i7PQ7noB7jYoTvjnPHI//IKwC/QFkfia+aXPPvJmhBA/azt6gGV pM8k4SvMtapnA== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 04D2BC5ACB3; Tue, 21 Nov 2023 10:17:19 +0000 (UTC) From: Nuno Sa via B4 Relay Subject: [PATCH 00/12] iio: add new backend framework Date: Tue, 21 Nov 2023 11:20:13 +0100 Message-Id: <20231121-dev-iio-backend-v1-0-6a3d542eba35@analog.com> Precedence: bulk X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-B4-Tracking: v=1; b=H4sIAF2EXGUC/x3MMQqAMAxA0atIZgOmFUSvIg6tiRqEVloQoXh3i +Mb/i+QJalkmJoCSW7NGkMFtQ2shwu7oHI1mM5YItMhy42qEb1bTwmMTL3vB+uIxw1qdSXZ9Pm P8/K+Hy4eIYhhAAAA To: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-iio@vger.kernel.org Cc: Olivier MOYSAN , Greg Kroah-Hartman , "Rafael J. Wysocki" , Rob Herring , Frank Rowand , Jonathan Cameron , Lars-Peter Clausen , Michael Hennerich , Nuno Sa X-Mailer: b4 0.12.4 X-Developer-Signature: v=1; a=ed25519-sha256; t=1700562016; l=5028; i=nuno.sa@analog.com; s=20231116; h=from:subject:message-id; bh=3Txu7PPyn6wb+lD0p7YfYmDJ0VmWJYBmGnKE5mN5Uvg=; b=EYGkUSMi6pIc/DEdOhknhZsaEsn+NJfPqBT/N8VADTcQg11HJ1dc4nH+Z+ZKHpoDtC2QnVjPt 0JVB7uKlQpDD48SBIN3/sdFRETQkq0NV+e1CHRxJdXKFSS5piBFk26A X-Developer-Key: i=nuno.sa@analog.com; a=ed25519; pk=3NQwYA013OUYZsmDFBf8rmyyr5iQlxV/9H4/Df83o1E= X-Endpoint-Received: by B4 Relay for nuno.sa@analog.com/20231116 with auth_id=100 X-Original-From: Nuno Sa Reply-To: Hi all, This is a Framework to handle complex IIO aggregate devices. The typical architecture is to have one device as the frontend device which can be "linked" against one or multiple backend devices. All the IIO and userspace interface is expected to be registers/managed by the frontend device which will callback into the backends when needed (to get/set some configuration that it does not directly control). The basic framework interface is pretty simple: - Backends should register themselves with @devm_iio_backend_register() - Frontend devices should get backends with @devm_iio_backend_get() (typical provider - consumer stuff) This is the result of the discussions in [1] and [2]. In short, both ADI and STM wanted some way to control/get configurations from a kind of IIO aggregate device. So discussions were made to have something that serves and can be used by everyone. The main differences with the converter framework RFC [1]: 1) Dropped the component framework. One can get more overview about the concerns on the references but the main reasons were: * Relying on providing .remove() callbacks to be allowed to use device managed functions. I was not even totally sure about the correctness of it and in times where everyone tries to avoid that driver callback, it could lead to some maintenance burden. * Scalability issues. As mentioned in [2], to support backends defined in FW child nodes was not so straightforward with the component framework. * Device links can already do some of the things that made me try the component framework (eg: removing consumers on suppliers unbind). 2) Only support the minimal set of functionality to have the devices in the same state as before using the backend framework. New features will be added afterwards. 3) Moved the API docs into the .c files. 4) Moved the framework to the IIO top dir and renamed it to industrialio-backend.c. Also, as compared with the RFC in [2], I don't think there are that many similarities other than the filename. However, it should now be pretty straight for Olivier to build on top of it. Also to mention that I did grabbed patch 1 ("of: property: add device link support for io-backends") from that series and just did some minor changes: 1) Renamed the property from "io-backend" to "io-backends". 2) No '#io-backend-cells' as it's not supported/needed by the framework (at least for now) . Regarding the driver core patch ("driver: core: allow modifying device_links flags"), it is more like a RFC one. I'm not really sure if the current behavior isn't just expected/wanted. Since I could not really understand if it is or not (or why the different handling DL_FLAG_AUTOREMOVE_CONSUMER vs DL_FLAG_AUTOREMOVE_SUPPLIER), I'm sending out the patch. Jonathan, I also have some fixes and cleanups for the ad9467 driver. I added Fixes tags but I'm not sure if it's really worth it to backport them (given what we already discussed about these drivers). I'll leave that to you :). I'm also not sure if I'm missing some tags (even though the series is frankly different from [2]). Olivier, If you want to be included as a Reviewer let me know and I'll happily do so in the next version. Also regarding the new IIO fw schemas. Should I send patches/PR to: https://github.com/devicetree-org/dt-schema/ ? Or is there any other workflow for it? [1]: https://lore.kernel.org/linux-iio/20230727150324.1157933-1-olivier.moysan@foss.st.com/ [2]: https://lore.kernel.org/linux-iio/20230727150324.1157933-1-olivier.moysan@foss.st.com/ --- Nuno Sa (11): driver: core: allow modifying device_links flags iio: add the IIO backend framework iio: adc: ad9467: fix reset gpio handling iio: adc: ad9467: don't ignore error codes iio: adc: ad9467: add mutex to struct ad9467_state iio: adc: ad9467: fix scale setting iio: adc: ad9467: use spi_get_device_match_data() iio: adc: ad9467: use chip_info variables instead of array iio: adc: ad9467: convert to backend framework iio: adc: adi-axi-adc: convert to regmap iio: adc: adi-axi-adc: move to backend framework Olivier Moysan (1): of: property: add device link support for io-backends MAINTAINERS | 7 + drivers/base/core.c | 14 +- drivers/iio/Kconfig | 5 + drivers/iio/Makefile | 1 + drivers/iio/adc/Kconfig | 3 +- drivers/iio/adc/ad9467.c | 382 +++++++++++++++++++++----------- drivers/iio/adc/adi-axi-adc.c | 429 +++++++----------------------------- drivers/iio/industrialio-backend.c | 302 +++++++++++++++++++++++++ drivers/of/property.c | 2 + include/linux/iio/adc/adi-axi-adc.h | 4 + include/linux/iio/backend.h | 58 +++++ 11 files changed, 723 insertions(+), 484 deletions(-) Thanks! - Nuno Sá