From patchwork Wed Nov 29 16:37:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miquel Raynal X-Patchwork-Id: 17286 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:a5a7:0:b0:403:3b70:6f57 with SMTP id d7csp463529vqn; Wed, 29 Nov 2023 08:37:47 -0800 (PST) X-Google-Smtp-Source: AGHT+IGEazzqPkmAucTHVx/ZEhefH6CtogIep+a6E6c1mCxtcflfd4/wIKolfc6sjzhOvklY02Tc X-Received: by 2002:a17:90a:f006:b0:285:777d:7b7f with SMTP id bt6-20020a17090af00600b00285777d7b7fmr28700115pjb.13.1701275866583; Wed, 29 Nov 2023 08:37:46 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1701275866; cv=none; d=google.com; s=arc-20160816; b=KXqxTASLrENyRNae5o3+UQsnsi8kBZAnZVq434zKTKifMD/JTP29M9XXnLIs1GYG1a hrlGHunGXm6k985mK0iewkKL6CvlJLi0sl7XU7R/HLOCJ0+gCDi6U2ObGZFE2YKbh0iN QBqaxJYW1z2BQku5H+gkB+bhbaFAbGEtmwX9r6PijgmF9K3BvHpXgnafukgVvswzKJHY 8SIohq9p2EZHex3WUKLBjOY01+r9CU1gsZFLu1Ef8oYqe2FfseOrs4GEsAQSL90m1X7a NWO9qQkmprRWBxrKV0733U+s7P8QQb1oE6+lfWlhEFmtDfsQAWA2byokz2XxV+PLyN2k azfQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :message-id:date:subject:cc:to:from:dkim-signature; bh=cd3989JJ1YTbZGbAiSzv5gEynjDTcribeidCsC3rKig=; fh=LHVfHqkxtSfhDK3Auz+HtR9CGNiwZCQHjp1a868hmsY=; b=SAxx8WIp6ANqXNsJe5kxUNmVxjdYweZ/c+0IJHCMChWUqDJRrHFTjiVgjGQcROBIdP +S6hnx3FVKFrCb7TFLKE0SWdYhxH2R05T4lDtjiRw/2wf7ABBOMjte4+oX6klSGKrNpx WeeEZgRZjxege2b7PTksnDPwPMNbfLYf8LUtFDJ4Cj7LgihAyOC42jqgyFfG9ZQrIYFP uLuA1jRjrShny/fRDic0FpMNI98C4syWAQ1ZSV89oBiq5V+TOP0KcRAZtwvld8aSYJq+ C3FHlaE04b/CUg1dy799BzEXll+d8fCLO0qlcpZmRR2vTWtTTxR/t9hnqJD4iNoscA1f G1HQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@bootlin.com header.s=gm1 header.b=FP280pcN; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=bootlin.com Received: from snail.vger.email (snail.vger.email. [2620:137:e000::3:7]) by mx.google.com with ESMTPS id q11-20020a635c0b000000b005a9fde46fa1si14351001pgb.343.2023.11.29.08.37.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Nov 2023 08:37:46 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) client-ip=2620:137:e000::3:7; Authentication-Results: mx.google.com; dkim=pass header.i=@bootlin.com header.s=gm1 header.b=FP280pcN; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=bootlin.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 31C77802FA58; Wed, 29 Nov 2023 08:37:45 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229705AbjK2Qhg (ORCPT + 99 others); Wed, 29 Nov 2023 11:37:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34074 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229485AbjK2Qhf (ORCPT ); Wed, 29 Nov 2023 11:37:35 -0500 Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [217.70.183.198]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F1C1C10A for ; Wed, 29 Nov 2023 08:37:40 -0800 (PST) Received: by mail.gandi.net (Postfix) with ESMTPSA id 0D8B2C0002; Wed, 29 Nov 2023 16:37:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1701275859; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=cd3989JJ1YTbZGbAiSzv5gEynjDTcribeidCsC3rKig=; b=FP280pcN2WPI2/1GxNF7TtAkpGdxIwXr0coSrE4zkMFzLBo2KjkX9GNTG7xd2ELiCh9dWg gJ+nD1aRgcG7iPzzbejwXQgK4UbTNy46dHWWjWv3NfRFHoGMurPWfVyPD4FsOk98Cctizc dj8yZ6IV3fOcswEUL7EXXhe5tPszVw6RkPZx38cdT+o2bVUq4GpArjT7VY0sdr/3opCZ9O hLpofxW0J+aSuCuv21Qr8/sLtvYJ0pe6kCiZeRTmiVl0QNLDrXwp0ayuWdETiB13jQKMcv 84XTB0MW+0SeY3GoLM2T0gi3EI/2n0HlW0RZTN1izxuOEOy1D8HnrBXiue+01w== From: Miquel Raynal To: Srinivas Kandagatla , Greg Kroah-Hartman , Cc: Thomas Petazzoni , Robert Marko , Luca Ceresoli , Michael Walle , =?utf-8?b?UmFmYcWCIE1pxYJlY2tp?= , Marco Felsch , Randy Dunlap , Chen-Yu Tsai , Daniel Golle , Miquel Raynal Subject: [PATCH v14 0/8] NVMEM cells in sysfs Date: Wed, 29 Nov 2023 17:37:29 +0100 Message-Id: <20231129163737.698317-1-miquel.raynal@bootlin.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-GND-Sasl: miquel.raynal@bootlin.com X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, RCVD_IN_MSPIKE_H5,RCVD_IN_MSPIKE_WL,SPF_HELO_PASS,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Wed, 29 Nov 2023 08:37:45 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1783917042872635938 X-GMAIL-MSGID: 1783917042872635938 Hello, As part of a previous effort, support for dynamic NVMEM layouts was brought into mainline, helping a lot in getting information from NVMEM devices at non-static locations. One common example of NVMEM cell is the MAC address that must be used. Sometimes the cell content is mainly (or only) useful to the kernel, and sometimes it is not. Users might also want to know the content of cells such as: the manufacturing place and date, the hardware version, the unique ID, etc. Two possibilities in this case: either the users re-implement their own parser to go through the whole device and search for the information they want, or the kernel can expose the content of the cells if deemed relevant. This second approach sounds way more relevant than the first one to avoid useless code duplication, so here is a series bringing NVMEM cells content to the user through sysfs. Here is a real life example with a Marvell Armada 7040 TN48m switch: $ nvmem=/sys/bus/nvmem/devices/1-00563/ $ for i in `ls -1 $nvmem/cells/*`; do basename $i; hexdump -C $i | head -n1; done country-code@77 00000000 54 57 |TW| crc32@88 00000000 bb cd 51 98 |..Q.| device-version@49 00000000 02 |.| diag-version@80 00000000 56 31 2e 30 2e 30 |V1.0.0| label-revision@4c 00000000 44 31 |D1| mac-address@2c 00000000 18 be 92 13 9a 00 |......| manufacture-date@34 00000000 30 32 2f 32 34 2f 32 30 32 31 20 31 38 3a 35 39 |02/24/2021 18:59| manufacturer@72 00000000 44 4e 49 |DNI| num-macs@6e 00000000 00 40 |.@| onie-version@61 00000000 32 30 32 30 2e 31 31 2d 56 30 31 |2020.11-V01| platform-name@50 00000000 38 38 46 37 30 34 30 2f 38 38 46 36 38 32 30 |88F7040/88F6820| product-name@d 00000000 54 4e 34 38 4d 2d 50 2d 44 4e |TN48M-P-DN| serial-number@19 00000000 54 4e 34 38 31 50 32 54 57 32 30 34 32 30 33 32 |TN481P2TW2042032| vendor@7b 00000000 44 4e 49 |DNI| Current support does not include: * The knowledge of the type of data (binary vs. ASCII), so by default all cells are exposed in binary form. * Write support. Changes in v14: * Fix all robot reports received so far. I also pushed the branch on my O-day repository until I got a successful feedback. * Changed a bit the Kconfig logic to only include layouts when CONFIG_OF is enabled, it does not make sense without any anyway (pointed by Marco). * Dropped the nvmem-layout dummy device, it is actually not relevant (pointed by Marco). * Fixed an allocation (reported by Marco). * Changed the nvmem-layout parent device to become the nvmem device (suggested by Marco). * Simplified the ->add_cells() hook in a dedicated (new) patch. * Moved and renamed ->fixup_cell_info() in a new patch. * We no longer try to modprobe explicitly the layout driver, this is no longer needed (pointed by Marco). * Updated the commit layouts with the latest changes. * Fixed the layouts exit path to regular fixed-layout descriptions (reported by Luca Ceresoli). * Tested and fixed the removal of the drivers. Tests have been performed using regular fixed layouts and the onie driver as layout provider with an Ethernet controller driver using an EEPROM exporting MAC addresses. Changes in v13: * Clarifying a NULL of_node situation was deemed irrelevant, so I dropped the patch. * Rename the layouts bus/devices: s/nvmem-layouts/nvmem-layout/. * Fixed incoherent function declarations returning void vs. int (kernel test robot). * Fixed another robot report related to the fact that an error path was only useful if CONFIG_NVMEM_SYSFS was enabled. * Collected tags. * We now register a struct nvmem_layout rather than a struct device as part of the layout bus. I had to create a couple of additional fields in the layout driver structure for that, but the final result looks nicer. Changes in v12: * Fixed the issues reported by kernel test robot. * Reworked even deeper the registration of layout devices and dropped all the research and matching code that was previously needed as suggested by Srinivas. This way, we no longer use the notifiers. Changes in v11: * The nvmem layouts are now regular devices and not platform devices anymore. They are registered into the nvmem-layout bus (so there is a new /sysfs/bus/nvmem-layouts entry that gets created. All the code for this new bus is located under drivers/nvmem/layouts.c and is part of the main core. The core device-driver logic applies without too much additional code besides the registration of the bus and a bit of glue. I see no need for more detailed structures for now but this can be improved later as needed. Changes in v10: * All preparation patches have been picked-up by Srinivas. * Rebased on top of v6.6-rc1. * Fix an error path in the probe due to the recent additions. Changes in v9: * Hopefully fixed the creation of sysfs entries when describing the cells using the legacy layout, as reported by Chen-Yu. * Dropped the nvmem-specific device list and used the driver core list instead as advised by Greg. Changes in v8: * Fix a compilation warning whith !CONFIG_NVMEM_SYSFS. * Add a patch to return NULL when no layout is found (reported by Dan Carpenter). * Fixed the documentation as well as the cover letter regarding the addition of addresses in the cell names. Changes in v7: * Rework the layouts registration mechanism to use the platform devices logic. * Fix the two issues reported by Daniel Golle and Chen-Yu Tsai, one of them consist in suffixing '@' to the cell name to create the sysfs files in order to be sure they are all unique. * Update the doc. Changes in v6: * ABI documentation style fixes reported by Randy Dunlap: s|cells/ folder|"cells" folder| Missing period at the end of the final note. s|Ex::|Example::| * Remove spurious patch from the previous resubmission. Resending v5: * I forgot the mailing list in my former submission, both are absolutely identical otherwise. Changes in v5: * Rebased on last -rc1, fixing a conflict and skipping the first two patches already taken by Greg. * Collected tags from Greg. * Split the nvmem patch into two, one which just moves the cells creation and the other which adds the cells. Changes in v4: * Use a core helper to count the number of cells in a list. * Provide sysfs attributes a private member which is the entry itself to avoid the need for looking up the nvmem device and then looping over all the cells to find the right one. Changes in v3: * Patch 1 is new: fix a style issue which bothered me when reading the core. * Patch 2 is new: Don't error out when an attribute group does not contain any attributes, it's easier for developers to handle "empty" directories this way. It avoids strange/bad solutions to be implemented and does not cost much. * Drop the is_visible hook as it is no longer needed. * Stop allocating an empty attribute array to comply with the sysfs core checks (this check has been altered in the first commits). * Fix a missing tab in the ABI doc. Changes in v2: * Do not mention the cells might become writable in the future in the ABI documentation. * Fix a wrong return value reported by Dan and kernel test robot. * Implement .is_bin_visible(). * Avoid overwriting the list of attribute groups, but keep the cells attribute group writable as we need to populate it at run time. * Improve the commit messages. * Give a real life example in the cover letter. Miquel Raynal (8): of: device: Export of_device_make_bus_id() nvmem: Move of_nvmem_layout_get_container() in another header nvmem: Create a header for internal sharing nvmem: Simplify the ->add_cells() hook nvmem: Move and rename ->fixup_cell_info() nvmem: core: Rework layouts to become regular devices ABI: sysfs-nvmem-cells: Expose cells through sysfs nvmem: core: Expose cells through sysfs Documentation/ABI/testing/sysfs-nvmem-cells | 21 ++ drivers/nvmem/Kconfig | 1 + drivers/nvmem/Makefile | 2 + drivers/nvmem/core.c | 335 ++++++++++++-------- drivers/nvmem/imx-ocotp.c | 11 +- drivers/nvmem/internals.h | 59 ++++ drivers/nvmem/layouts.c | 201 ++++++++++++ drivers/nvmem/layouts/Kconfig | 8 + drivers/nvmem/layouts/onie-tlv.c | 27 +- drivers/nvmem/layouts/sl28vpd.c | 27 +- drivers/nvmem/mtk-efuse.c | 11 +- drivers/of/device.c | 41 +++ drivers/of/platform.c | 40 --- include/linux/nvmem-consumer.h | 7 - include/linux/nvmem-provider.h | 64 ++-- include/linux/of_device.h | 6 + 16 files changed, 624 insertions(+), 237 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-nvmem-cells create mode 100644 drivers/nvmem/internals.h create mode 100644 drivers/nvmem/layouts.c Tested-by: Luca Ceresoli