From patchwork Thu Feb 17 16:26:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrea Merello X-Patchwork-Id: 12750417 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC029C433F5 for ; Thu, 17 Feb 2022 16:27:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243102AbiBQQ1h (ORCPT ); Thu, 17 Feb 2022 11:27:37 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:59792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234411AbiBQQ1h (ORCPT ); Thu, 17 Feb 2022 11:27:37 -0500 Received: from mail-ej1-x62d.google.com (mail-ej1-x62d.google.com [IPv6:2a00:1450:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 670C59A9A3; Thu, 17 Feb 2022 08:27:22 -0800 (PST) Received: by mail-ej1-x62d.google.com with SMTP id p14so8492647ejf.11; Thu, 17 Feb 2022 08:27:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=cugFVa2TaBWmSwBVtyXgkeptt7jXSE4VzCQ/5gV5rpU=; b=K12VJmHxzg8jBXj32woZbaXUplVy21O4g5lIYY3/ZUrVKXJFGJ0wpiGJDDyxA6K+px 2nkqBN3FMK9cRSoUfaFUYUWCUPJfl2TlwzO9JSJHoCjmoqAoodTXYTm5K1QJFgIUxNuA +g0La8oP9nSOzVhjjUzoIYsA9b3X76g9SCHCCHxrrRzw59yPR52rJUOgZoAGgwndmAhk KdbiWXkvslm5lRuSfPTfqq5rR2sUfaCiLERT3Ko5NAWi072dqgpLSYSWgjB0c4jVS4iv 5b7BZR7i3/2DeEPlzL26GIFRP7yFd2WBpYdo7P0N5ftIw0UnkuRMwtktqfL3cypggBP6 MZJA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=cugFVa2TaBWmSwBVtyXgkeptt7jXSE4VzCQ/5gV5rpU=; b=kT/lqVPwtDBq+PuXueGGr/4XCns+N/gkQ88t4LB3hK6g2q2eo8AITPV80AsWHXXtQY MAAuhnAMgQZ3pnASOplf3EOgVKiPCRlQ+rLy0935l7vH4oAiz5Ub0M7LBzj1X9C5G8ma gd8KedXq9VqPtgnsqymRQV086TxUH+0NF9Xy6Nk7vX54ZqhwKxU/wLsh6VlkNc5UiBQl 8LOGxjyOEz0XPSpegK/OYQOQAl9Z8C4IQNDdHuGPo9YIJ6bj+uv3bH90thWBCi36lrfs yirxgs1dI4qyGLenpzxdzI9PcdZFd8lv+a3oeP+LyTRoLwb379+r54MI1P5dqY5PT+mc JXDQ== X-Gm-Message-State: AOAM531APWFW/kKgtOSbrLR/u6wWFRf49gCn6oOVxyg6QuQ2Ijl8qZo5 n1XMQXOOqAo0cjllDAf7ucw= X-Google-Smtp-Source: ABdhPJxUGYugDqGuLtoRk3wPQVSl0L7gB4pxFZ1N2bp7NCtP3kt2Mr6jWtLNpduazYSbYkja5TEvcA== X-Received: by 2002:a17:906:d298:b0:6cf:9baf:468 with SMTP id ay24-20020a170906d29800b006cf9baf0468mr2909703ejb.61.1645115240780; Thu, 17 Feb 2022 08:27:20 -0800 (PST) Received: from poker.lan (static.2-229-210-222.ip198.fastwebnet.it. [2.229.210.222]) by smtp.gmail.com with ESMTPSA id j13sm3653742edw.24.2022.02.17.08.27.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Feb 2022 08:27:20 -0800 (PST) From: Andrea Merello To: jic23@kernel.org, mchehab+huawei@kernel.org, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Cc: lars@metafoo.de, robh+dt@kernel.org, andy.shevchenko@gmail.com, matt.ranostay@konsulko.com, ardeleanalex@gmail.com, jacopo@jmondi.org, Andrea Merello Subject: [v3 00/13] Add support for Bosch BNO055 IMU Date: Thu, 17 Feb 2022 17:26:57 +0100 Message-Id: <20220217162710.33615-1-andrea.merello@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org This series (tries to) add support for Bosch BNO055 IMU to Linux IIO subsystem. It is made up several patches: 1/13 to 6/13: add some IIO modifiers, and their documentation, to the IIO core layer, in order to being able to expose the linear acceleration and Euler angles among standard attributes. Also update the IIO event monitor tool 6/13 to 10/13: add the core IIO BNO055 driver documentation for sysfs attributes and DT bindings 11/13: adds serdev BNO055 driver to actually use the IMU via serial line 12/13: adds I2C BNO055 driver to actually use the IMU via I2C wiring 13/13: add a documentation file that describe the bno055 driver and specifically the calibration Differences wrt v2: FIXES: - workaround: switching off and on fusion mode could cause IMU to misbehave (i.e. wrong anglvel data) - FIX sometimes driver failed to write attributes / manual settings were not honored - workaround: for IMU gyroscope unit bug (unit change by changing range) - Fixed some typos bosh->bosch - Fixed warning caught by kernel robot - Fix bursting was broken - Fix missing mutex unlock in exit path API: - rework sysfs attribute names - change linear acceleration modifiers names (e.g. ACCEL_LINEAR_MOD -> ACCEL_MOD) - 'unique_id' sysfs attribute become 'serial_number' and become non-bno055-specific - fix range units and sysfs names - fix gyro lpf available values were returned in twisted order - gyroscope no longer has the range attribute, the scale can now be changed instead Misc: - Dropped previous patch 01 (add find_closest_unsorted) as it is not needed anymore - Some trivial stuff (commas, newlines etc) - Added help section in Kconfig - reworked sysfs attribute code, to easier implement required API changes and above fixes - hopefully implement all reviewers advice (e.g. rid of macro helpers, kill useless devm primitive, simplify bno055_clk_disable, rework some bail-out code, conditions check, remove odd usage of ternary operator, move default clause at end of switch block, etc ..) - reorder patches so that DOC for a new thing come after patch that introduced that thing - linear acceleration DOC moved and cross-referenced to acceleration doc Differences wrt other BNO055 drivers: Previously at least another driver for the very same chip has been posted to the Linux ML [0], but it has been never merged, and it seems no one cared of it since quite a long time. This driver differs from the above driver on the following aspects: - This driver supports also serial access (to be reliable, reset pin is required to be wired) - The above driver tried to support all IMU HW modes by allowing to choose one in the DT, and adapting IIO attributes accordingly. This driver does not rely on DT for this, instead settings are done via sysfs attributes. All IIO attributes are always exposed; more on this later on. This driver however supports only a subset of the HW-supported modes. - This driver has some support for managing the IMU calibration Supported operation modes: - AMG (accelerometer, magnetometer and gyroscope) mode, which provides raw (uncalibrated) measurements from the said sensors, and allows for setting some parameters about them (e.g. filter cut-off frequency, max sensor ranges, etc). - Fusion mode, which still provides AMG measures, while it also provides other data calculated by the IMU (e.g. rotation angles, linear acceleration, etc). In this mode user has no freedom to set any sensor parameter, since the HW locks them. Autocalibration and correction is performed by the IMU. IIO attributes exposing sensors parameters are always present, but in fusion modes the available values are constrained to just the one used by the HW. This is reflected in the '*_available' IIO attributes. Trying to set a not-supported value always falls back to the closest supported one, which in this case is just the one in use by the HW. IIO attributes for unavailable measurements (e.g. Euler angles in AMG mode) just read zero (which is consistent WRT what you get when reading from a buffer with those attributes enabled). IMU calibration: The IMU supports for two sets of calibration parameters: - SIC matrix. user-provided; this driver doesn't currently support it - Offset and radius parameters. The IMU automatically finds out them when it is running in fusion mode; supported by this driver. The driver provides access to autocalibration flags (i.e. you can known if the IMU has successfully autocalibrated) and to calibration data blob. The user can save this blob in a "firmware" file (i.e. in /lib/firmware) that the driver looks for at probe time. If found, then the IMU is initialized with this calibration data. This saves the user from performing the calibration procedure every time (which consist of moving the IMU in various way). The driver looks for calibration data file using two different names: first a file whose name is suffixed with the IMU unique ID is searched for; this is useful when there is more than one IMU instance. If this file is not found, then a "generic" calibration file is searched for (which can be used when only one IMU is present, without struggling with fancy names, that changes on each device). In AMG mode the IIO 'offset' attributes provide access to the offsets from calibration data (if any), so that the user can apply them to the accel, angvel and magn IIO attributes. In fusion mode they are not needed and read as zero. Access protocols and serdev module: The serial protocol is quite simple, but there are tricks to make it really works. Those tricks and workarounds are documented in the driver source file. The core BNO055 driver tries to group readings in burst when appropriate, in order to optimize triggered buffer operation. The threshold for splitting a burst (i.e. max number of unused bytes in the middle of a burst that will be throw away) is provided to the core driver by the lowlevel access driver (either serdev or I2C) at probe time. [0] https://www.spinics.net/lists/linux-iio/msg25508.html Andrea Merello (13): iio: add modifiers for linear acceleration iio: document linear acceleration modifiers iio: event_monitor: add linear acceleration modifiers iio: add modifers for pitch, yaw, roll iio: document pitch, yaw, roll modifiers iio: event_monitor: add pitch, yaw and roll modifiers iio: imu: add Bosch Sensortec BNO055 core driver iio: document bno055 private sysfs attributes iio: document "serial_number" sysfs attribute dt-bindings: iio: imu: add documentation for Bosch BNO055 bindings iio: imu: add BNO055 serdev driver iio: imu: add BNO055 I2C driver docs: iio: add documentation for BNO055 driver Documentation/ABI/testing/sysfs-bus-iio | 25 + .../ABI/testing/sysfs-bus-iio-bno055 | 81 + .../bindings/iio/imu/bosch,bno055.yaml | 59 + Documentation/iio/bno055.rst | 53 + drivers/iio/imu/Kconfig | 1 + drivers/iio/imu/Makefile | 1 + drivers/iio/imu/bno055/Kconfig | 25 + drivers/iio/imu/bno055/Makefile | 5 + drivers/iio/imu/bno055/bno055.c | 1612 +++++++++++++++++ drivers/iio/imu/bno055/bno055.h | 12 + drivers/iio/imu/bno055/bno055_i2c.c | 50 + drivers/iio/imu/bno055/bno055_sl.c | 557 ++++++ drivers/iio/industrialio-core.c | 6 + include/uapi/linux/iio/types.h | 7 +- tools/iio/iio_event_monitor.c | 6 + 15 files changed, 2499 insertions(+), 1 deletion(-) create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-bno055 create mode 100644 Documentation/devicetree/bindings/iio/imu/bosch,bno055.yaml create mode 100644 Documentation/iio/bno055.rst create mode 100644 drivers/iio/imu/bno055/Kconfig create mode 100644 drivers/iio/imu/bno055/Makefile create mode 100644 drivers/iio/imu/bno055/bno055.c create mode 100644 drivers/iio/imu/bno055/bno055.h create mode 100644 drivers/iio/imu/bno055/bno055_i2c.c create mode 100644 drivers/iio/imu/bno055/bno055_sl.c --- 2.17.1