From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F1721C43460 for ; Tue, 20 Apr 2021 08:12:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BFAF86113C for ; Tue, 20 Apr 2021 08:12:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230237AbhDTINY (ORCPT ); Tue, 20 Apr 2021 04:13:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229551AbhDTINW (ORCPT ); Tue, 20 Apr 2021 04:13:22 -0400 Received: from mail-pf1-x431.google.com (mail-pf1-x431.google.com [IPv6:2607:f8b0:4864:20::431]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 111CBC06174A; Tue, 20 Apr 2021 01:12:52 -0700 (PDT) Received: by mail-pf1-x431.google.com with SMTP id q2so667519pfk.9; Tue, 20 Apr 2021 01:12:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=6R19o6MmOB2V6vb1xz4WbMriyBMESBV6aV0z6YGJtHM=; b=Ae8KomhNCrqj3CFeW1A9JSxCYKA00ELKGISgGV5o40+/LPLKJV+4a834bDmII79bqD WGGqFHBTCX5aXNMmnvrcxntyaU8ZZVFLNf3g6xRK6stydp7cJ8Y9uJmtM4lNqlObfxnI F7e5/GwBpg/P5+kKccWpMGIPCGRb30Y9YQRppOa0tb8iGYenlCER1s5Gs5aFcpfmQOcC 5LJ3IlY8B5XXv9hg4TyAmRvb9K9m5uxj1I/qn3ANMZwjqqGMSe8cAIXQJAqOw57djIif CNZ/+0NjjtNUt2Zv6yyH4xYnm4BtqA9FO03LbPJG4cC4triWT71F1IzE+v0rGzswamEt cdNQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=6R19o6MmOB2V6vb1xz4WbMriyBMESBV6aV0z6YGJtHM=; b=XTGKFd/IZiIJY2bjyzjcGIiHLI0+J9m/uZ9f47UdAYef9Z+CRoiJA8Ggi9OUCSHAb5 Oj0BCUPxpfP0rsGgh1eIbBtDi1xSxnTlFN8qMhlAOqXC7RmhWiWTowmBQMXj9UTnhDs9 QB/rVmJkMGO17pe2GnTmmBNrRT/VnlbIigc9yeVrHuarI9ogeF3nDFn5xceewnRCxfIr 2UEehu9rbKDEk2J+jqQyiaimm+LfCuO1Kki5fhp/4fRbNFN3HDix5sY4Eq1xVUjKbT/y soGbDLrzyfWJfgeItTfMYDXSpuqxfJS4UGRTMCy8MP1kdy5eP3RPxWJ1pOcvhI/yd+me aI1A== X-Gm-Message-State: AOAM532ID+zDD+vttxly23P48HL5rXXAPg99COioeTGoU6XpvQmJPtU0 WQiAwbehRmUNNPI+TYMhMMmWhaRUaY5OZ6glwBxb/yZ/cEXcFw== X-Google-Smtp-Source: ABdhPJyiTVDoM6jxBFNBEhdkUt9SPWLUHi0a/vDgLAwWkGcXJVZcbUqgKIK1eMqYS1JvaugOaUM4NxR/KSIyo8w+t1Q= X-Received: by 2002:aa7:904e:0:b029:25a:4469:222a with SMTP id n14-20020aa7904e0000b029025a4469222amr17868910pfo.72.1618906371323; Tue, 20 Apr 2021 01:12:51 -0700 (PDT) MIME-Version: 1.0 References: <20210412075056.56301-1-tomas.melin@vaisala.com> <20210412075056.56301-3-tomas.melin@vaisala.com> <20210412120807.000044d3@Huawei.com> <87302341-f9d0-372a-1f18-b934df202e82@vaisala.com> <1541221b-3dd3-9cc6-1dfe-6a4a100579d0@vaisala.com> <20210418110319.72694b7e@jic23-huawei> <20210419204509.527570a3@jic23-huawei> <20210419211622.0f57f2ef@jic23-huawei> In-Reply-To: <20210419211622.0f57f2ef@jic23-huawei> From: Alexandru Ardelean Date: Tue, 20 Apr 2021 11:12:39 +0300 Message-ID: Subject: Re: [PATCH 2/2] iio: accel: Add driver for Murata SCA3300 accelerometer To: Jonathan Cameron Cc: Tomas Melin , Jonathan Cameron , devicetree , linux-iio , LKML , Alexandru Ardelean Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ( On Mon, Apr 19, 2021 at 11:15 PM Jonathan Cameron wrote: > > On Mon, 19 Apr 2021 20:45:08 +0100 > Jonathan Cameron wrote: > > > On Mon, 19 Apr 2021 16:34:35 +0300 > > Tomas Melin wrote: > > > > > Hi, > > > > > > On 4/18/21 1:03 PM, Jonathan Cameron wrote: > > > > On Fri, 16 Apr 2021 15:21:14 +0300 > > > > Tomas Melin wrote: > > > > > > > >> Updated email-address for Alexandru. > > > >> > > > >> > > > >> On 4/16/21 3:17 PM, Tomas Melin wrote: > > > >>> On 4/15/21 11:41 AM, Tomas Melin wrote: > > > >>> > > > >>>> While working on updates I did notice something new which I cannot > > > >>>> > > > >>>> reproduce on older (5.10.17 kernel) version. If compiling this as a > > > >>>> module, getting error while > > > >>>> > > > >>>> unloading module: > > > >>>> > > > >>>> [ 40.200084] Unable to handle kernel NULL pointer dereference at > > > >>>> virtual address 00000104 > > > >>>> ... > > > >>>> > > > >>>> [ 40.510054] Backtrace: > > > >>>> [ 40.512502] [] (iio_device_ioctl_handler_unregister) > > > >>>> from [] (iio_buffers_free_sysfs_and_mask+0x2c/0x6c) > > > >>>> [ 40.523735] [] (iio_buffers_free_sysfs_and_mask) from > > > >>>> [] (iio_device_unregister+0xa8/0xac) > > > >>>> [ 40.533746] r5:c1811228 r4:c1811000 > > > >>>> [ 40.537318] [] (iio_device_unregister) from [] > > > >>>> (devm_iio_device_unreg+0x1c/0x20) > > > >>>> [ 40.546461] r5:c2415000 r4:c25bab80 > > > >>>> [ 40.550025] [] (devm_iio_device_unreg) from [] > > > >>>> (release_nodes+0x1c0/0x1f0) > > > >>>> [ 40.558654] [] (release_nodes) from [] > > > >>>> (devres_release_all+0x40/0x60) > > > >>>> [ 40.566847] r10:00000081 r9:c2350000 r8:c0100264 r7:00000081 > > > >>>> r6:bf00c010 r5:c19be000 > > > >>>> [ 40.574669] r4:c1a91c00 > > > >>>> [ 40.577194] [] (devres_release_all) from [] > > > >>>> (device_release_driver_internal+0x120/0x1cc) > > > >>>> [ 40.587031] r5:c19be000 r4:c1a91c00 > > > >>>> [ 40.590596] [] (device_release_driver_internal) from > > > >>>> [] (driver_detach+0x54/0x90) > > > >>>> [ 40.599828] r7:00000081 r6:00000000 r5:bf00c010 r4:c1a91c00 > > > >>>> [ 40.605482] [] (driver_detach) from [] > > > >>>> (bus_remove_driver+0x5c/0xb0) > > > >>>> [ 40.613583] r5:00000800 r4:bf00c010 > > > >>>> [ 40.617148] [] (bus_remove_driver) from [] > > > >>>> (driver_unregister+0x38/0x5c) > > > >>>> [ 40.625596] r5:00000800 r4:bf00c010 > > > >>>> [ 40.629161] [] (driver_unregister) from [] > > > >>>> (sca3300_driver_exit+0x14/0x8b4 [sca3300]) > > > >>>> [ 40.638747] r5:00000800 r4:bf00c080 > > > >>>> [ 40.642311] [] (sca3300_driver_exit [sca3300]) from > > > >>>> [] (sys_delete_module+0x16c/0x238) > > > >>>> [ 40.651990] [] (sys_delete_module) from [] > > > >>>> (__sys_trace_return+0x0/0x1c) > > > >>>> [ 40.660435] Exception stack(0xc2351fa8 to 0xc2351ff0) > > > >>>> [ 40.665484] 1fa0: 0050e5a8 00000000 0050e5e4 > > > >>>> 00000800 081d4b00 bec18af4 > > > >>>> [ 40.673661] 1fc0: 0050e5a8 00000000 bec18b50 00000081 bec18e51 > > > >>>> 0050e190 00000001 bec18d3c > > > >>>> [ 40.681834] 1fe0: 0050cf70 bec18afc 004f1ec8 b6ecb27c > > > >>>> [ 40.686887] r6:bec18b50 r5:00000000 r4:0050e5a8 > > > >>>> [ 40.691507] Code: e8bd4000 e1c020d0 e3a0cc01 e3001122 (e5823004) > > > >>>> [ 40.707675] ---[ end trace 189882b050077333 ]--- > > > >>>> > > > >>>> This happens when building against linux-next > > > >>>> 5.12.0-rc6-next-20210409. I'm failing to see what is wrong. Any ideas? > > > >>>> > > > >>>> Thanks, > > > >>>> > > > >>>> Tomas > > > >>> > > > >>> Tested further that for this driver, loading and unloading as module > > > >>> works fine until commit: > > > >>> > > > >>> commit f73f7f4da581875f9b1f2fb8ebd1ab15ed634488 > > > >>> Author: Alexandru Ardelean > > > >>> Date: Mon Feb 15 12:40:39 2021 +0200 > > > >>> > > > >>> iio: buffer: add ioctl() to support opening extra buffers for IIO > > > >>> device > > > >>> > > > >>> > > > >>> Any thoughts what causes this issue? > > > > Is this still happening after fixing the ordering in probe / remove? > > > > (devm_iio_triggered_buffer_setup() being easiest way) > > > > > > > > As driver currently stands it's calling iio_triggered_buffer_cleanup > > > > before the managed cleanup of the iio_device_register() call. That > > > > should never happen so would be where I'd look for problems here. > > > > > > > > It is possible Alex's work is relying on that ordering being correct > > > > a little more than we previously were. I could be wrong though > > > > and could be something else going on! > > > > > > > > Jonathan > > > > > > > > +CC Alex's other email address. > > > > > > This is still happening with v3 of driver patchset, which uses only devm_* > > > > > > versions in probing. v5.12-rc7 works ok, I'm currently only seeing this > > > using linux-next. > > > > Thanks for checking. I've just fired up a VM and confirmed that the same > > thing is happening with creating and removing instances of the dummy driver. > > > > Will see if I can figure out what's going wrong. > > So the issue proved reasonably easy to track down. > We remove the buffer ioctl handler twice. First in iio_device_unregister() in a loop > over the list, and again later in iio_buffer_sysfs_and_mask() (called from > the same function). (note it would happen later in the equivalent event related > version but we have already died on the first instance which is the one Tomas hit). > > @Alex. Which one should we keep? Given the buffer and event code both > clean up manually I think what we want is: > > @@ -1939,9 +1943,6 @@ void iio_device_unregister(struct iio_dev *indio_dev) > > indio_dev->info = NULL; > > - list_for_each_entry_safe(h, t, &iio_dev_opaque->ioctl_handlers, entry) > - list_del(&h->entry); > - > iio_device_wakeup_eventset(indio_dev); > iio_buffer_wakeup_poll(indio_dev); > > > I'm going to guess something went wrong in a merge or rebased and left that > block when it should have been removed. No, that's not a merge/rebase gone wrong. It's me being stupid. Removing that loop is the good fix. Each module doing a iio_device_ioctl_handler_register() should also do a iio_device_ioctl_handler_unregister(). > > Anyhow, if the above is the right fix I can roll it up into a patch tomorrow and > get it into linux-next at least. Sure :) Apologies for the breakage. > > thanks, > > Jonathan > > > > > Jonathan > > > > > > > > Thanks, > > > > > > Tomas > > > > > > > > > >>> Thanks, > > > >>> > > > >>> Tomas > > > >>> > > > >>> > > > >>> > > > >>>> > > > >>>>> > > > >>>>>> --- > > > >>>>>> drivers/iio/accel/Kconfig | 13 ++ > > > >>>>>> drivers/iio/accel/Makefile | 1 + > > > >>>>>> drivers/iio/accel/sca3300.c | 434 > > > >>>>>> ++++++++++++++++++++++++++++++++++++ > > > >>>>>> 3 files changed, 448 insertions(+) > > > >>>>>> create mode 100644 drivers/iio/accel/sca3300.c > > > >>>>>> > > > >>>>>> diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig > > > >>>>>> index cceda3cecbcf..0dbf7b648e8a 100644 > > > >>>>>> --- a/drivers/iio/accel/Kconfig > > > >>>>>> +++ b/drivers/iio/accel/Kconfig > > > >>>>>> @@ -450,6 +450,19 @@ config SCA3000 > > > >>>>>> To compile this driver as a module, say M here: the module > > > >>>>>> will be > > > >>>>>> called sca3000. > > > >>>>>> +config SCA3300 > > > >>>>>> + tristate "Murata SCA3300 3-Axis Accelerometer Driver" > > > >>>>>> + depends on SPI > > > >>>>>> + select CRC8 > > > >>>>>> + select IIO_BUFFER > > > >>>>>> + select IIO_TRIGGERED_BUFFER > > > >>>>>> + help > > > >>>>>> + Say yes here to build support for Murata SCA3300 3-Axis > > > >>>>>> + accelerometer. > > > >>>>>> + > > > >>>>>> + To compile this driver as a module, choose M here: the > > > >>>>>> module will be > > > >>>>>> + called sca3300. > > > >>>>>> + > > > >>>>>> config STK8312 > > > >>>>>> tristate "Sensortek STK8312 3-Axis Accelerometer Driver" > > > >>>>>> depends on I2C > > > >>>>>> diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile > > > >>>>>> index 32cd1342a31a..4b56527a2b97 100644 > > > >>>>>> --- a/drivers/iio/accel/Makefile > > > >>>>>> +++ b/drivers/iio/accel/Makefile > > > >>>>>> @@ -50,6 +50,7 @@ obj-$(CONFIG_MXC4005) += mxc4005.o > > > >>>>>> obj-$(CONFIG_MXC6255) += mxc6255.o > > > >>>>>> obj-$(CONFIG_SCA3000) += sca3000.o > > > >>>>>> +obj-$(CONFIG_SCA3300) += sca3300.o > > > >>>>>> obj-$(CONFIG_STK8312) += stk8312.o > > > >>>>>> obj-$(CONFIG_STK8BA50) += stk8ba50.o > > > >>>>>> diff --git a/drivers/iio/accel/sca3300.c b/drivers/iio/accel/sca3300.c > > > >>>>>> new file mode 100644 > > > >>>>>> index 000000000000..112fb88ecd3a > > > >>>>>> --- /dev/null > > > >>>>>> +++ b/drivers/iio/accel/sca3300.c > > > >>>>>> @@ -0,0 +1,434 @@ > > > >>>>>> +// SPDX-License-Identifier: GPL-2.0-only > > > >>>>>> +/* > > > >>>>>> + * Copyright (c) Vaisala Oyj. All rights reserved. > > > >>>>> Give a year for the copyright notice if you can. > > > >>>>> > > > >>>>>> + */ > > > >>>>>> +#include > > > >>>>>> +#include > > > >>>>>> +#include > > > >>>>>> +#include > > > >>>>>> +#include > > > >>>>>> +#include > > > >>>>>> +#include > > > >>>>>> +#include > > > >>>>>> +#include > > > >>>>>> +#include > > > >>>>>> + > > > >>>>>> +#define SCA3300_ALIAS "sca3300" > > > >>>>>> + > > > >>>>>> +#define SCA3300_REG_STATUS 0x6 > > > >>>>>> +#define SCA3300_REG_MODE 0xd > > > >>>>>> +#define SCA3300_REG_WHOAMI 0x10 > > > >>>>>> +#define SCA3300_VALUE_SW_RESET 0x20 > > > >>>>>> +#define SCA3300_CRC8_POLYNOMIAL 0x1d > > > >>>>>> +#define SCA3300_X_READ 0 > > > >>>>> I wouldn't bother defining this. > > > >>>>> > > > >>>>>> +#define SCA3300_X_WRITE BIT(7) > > > >>>>> Even this one is something I'd just put inline with a comment. > > > >>>>> > > > >>>>>> +#define SCA3300_DEVICE_ID 0x51 > > > >>>>>> +#define SCA3300_RS_ERROR 0x3 > > > >>>>>> + > > > >>>>>> +enum sca3300_scan_indexes { > > > >>>>>> + SCA3300_ACC_X = 0, > > > >>>>>> + SCA3300_ACC_Y, > > > >>>>>> + SCA3300_ACC_Z, > > > >>>>>> + SCA3300_TEMP, > > > >>>>>> + SCA3300_TIMESTAMP, > > > >>>>>> +}; > > > >>>>>> + > > > >>>>>> +#define SCA3300_ACCEL_CHANNEL(index, reg, axis) { \ > > > >>>>>> + .type = IIO_ACCEL, \ > > > >>>>>> + .address = reg, \ > > > >>>>>> + .modified = 1, \ > > > >>>>>> + .channel2 = IIO_MOD_##axis, \ > > > >>>>>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ > > > >>>>>> + BIT(IIO_CHAN_INFO_PROCESSED), \ > > > >>>>> As mentioned below, don't provide PROCESSED. Userspace is better at > > > >>>>> handling the > > > >>>>> conversion so leave it to them. > > > >>>>> > > > >>>>>> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > > > >>>>>> + .scan_index = index, \ > > > >>>>>> + .scan_type = { \ > > > >>>>>> + .sign = 's', \ > > > >>>>>> + .realbits = 16, \ > > > >>>>>> + .storagebits = 16, \ > > > >>>>>> + .shift = 0, \ > > > >>>>>> + .endianness = IIO_CPU, \ > > > >>>>>> + }, \ > > > >>>>>> + } > > > >>>>>> + > > > >>>>>> +static const struct iio_chan_spec sca3300_channels[] = { > > > >>>>>> + SCA3300_ACCEL_CHANNEL(SCA3300_ACC_X, 0x1, X), > > > >>>>>> + SCA3300_ACCEL_CHANNEL(SCA3300_ACC_Y, 0x2, Y), > > > >>>>>> + SCA3300_ACCEL_CHANNEL(SCA3300_ACC_Z, 0x3, Z), > > > >>>>>> + { > > > >>>>>> + .type = IIO_TEMP, > > > >>>>>> + .address = 0x5, > > > >>>>>> + .scan_index = SCA3300_TEMP, > > > >>>>>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), > > > >>>>>> + .scan_type = { > > > >>>>>> + .sign = 's', > > > >>>>>> + .realbits = 16, > > > >>>>>> + .storagebits = 16, > > > >>>>>> + .shift = 0, > > > >>>>>> + .endianness = IIO_CPU, > > > >>>>>> + }, > > > >>>>>> + }, > > > >>>>>> + IIO_CHAN_SOFT_TIMESTAMP(4), > > > >>>>>> +}; > > > >>>>>> + > > > >>>>>> +static const int sca3300_accel_scale[] = {2700, 1350, 5400, 5400}; > > > >>>>>> + > > > >>>>>> +static const unsigned long sca3300_scan_masks[] = { > > > >>>>>> + BIT(SCA3300_ACC_X) | BIT(SCA3300_ACC_Y) | BIT(SCA3300_ACC_Z) | > > > >>>>>> + BIT(SCA3300_TEMP), > > > >>>>>> + 0}; > > > >>>>>> + > > > >>>>>> +/** > > > >>>>>> + * SCA3300 device data > > > >>>>> run scripts/kernel-doc over the file and fix the warnings + errors. > > > >>>>> > > > >>>>>> + * > > > >>>>>> + * @spi SPI device structure > > > >>>>>> + * @opmode Device operation mode > > > >>>>>> + * @lock Data buffer lock > > > >>>>>> + * @txbuf Transmit buffer > > > >>>>>> + * @rxbuf Receive buffer > > > >>>>>> + * @scan Triggered buffer. Four channel 16-bit data + 64-bit > > > >>>>>> timestamp > > > >>>>>> + */ > > > >>>>>> +struct sca3300_data { > > > >>>>>> + struct spi_device *spi; > > > >>>>>> + u32 opmode; > > > >>>>>> + struct mutex lock; > > > >>>>>> + u8 txbuf[4]; > > > >>>>>> + u8 rxbuf[4]; > > > >>>>>> + struct { > > > >>>>>> + s16 channels[4]; > > > >>>>>> + s64 ts __aligned(sizeof(s64)); > > > >>>>>> + } scan; > > > >>>>>> +}; > > > >>>>>> + > > > >>>>>> +DECLARE_CRC8_TABLE(sca3300_crc_table); > > > >>>>>> + > > > >>>>>> +static int sca3300_transfer(struct sca3300_data *sca_data, int *val) > > > >>>>>> +{ > > > >>>>>> + struct spi_delay delay = {.value = 10, .unit = > > > >>>>>> SPI_DELAY_UNIT_USECS}; > > > >>>>>> + int32_t ret; > > > >>>>>> + int rs; > > > >>>>>> + u8 crc; > > > >>>>>> + struct spi_transfer xfers[2] = { > > > >>>>>> + { > > > >>>>>> + .tx_buf = sca_data->txbuf, > > > >>>>>> + .rx_buf = NULL, > > > >>>>>> + .len = ARRAY_SIZE(sca_data->txbuf), > > > >>>>>> + .delay = delay, > > > >>>>>> + .cs_change = 1, > > > >>>>>> + }, > > > >>>>>> + { > > > >>>>>> + .tx_buf = NULL, > > > >>>>>> + .rx_buf = sca_data->rxbuf, > > > >>>>>> + .len = ARRAY_SIZE(sca_data->rxbuf), > > > >>>>>> + .delay = delay, > > > >>>>>> + .cs_change = 0, > > > >>>>>> + } > > > >>>>>> + }; > > > >>>>>> + > > > >>>>>> + /* inverted crc value as described in device data sheet */ > > > >>>>>> + crc = ~crc8(sca3300_crc_table, &sca_data->txbuf[0], 3, > > > >>>>>> CRC8_INIT_VALUE); > > > >>>>>> + sca_data->txbuf[3] = crc; > > > >>>>>> + > > > >>>>>> + ret = spi_sync_transfer(sca_data->spi, xfers, 2); > > > >>>>> Use ARRAY_SIZE(xfers) instead of 2. > > > >>>>> > > > >>>>>> + if (ret < 0) { > > > >>>>>> + dev_err(&sca_data->spi->dev, > > > >>>>>> + "transfer error, error: %d\n", ret); > > > >>>>>> + return -EIO; > > > >>>>>> + } > > > >>>>>> + > > > >>>>>> + crc = ~crc8(sca3300_crc_table, &sca_data->rxbuf[0], 3, > > > >>>>>> CRC8_INIT_VALUE); > > > >>>>>> + if (sca_data->rxbuf[3] != crc) { > > > >>>>>> + dev_err(&sca_data->spi->dev, "CRC checksum mismatch"); > > > >>>>>> + return -EIO; > > > >>>>>> + } > > > >>>>>> + > > > >>>>>> + /* get return status */ > > > >>>>>> + rs = sca_data->rxbuf[0] & 0x03; > > > >>>>>> + if (rs == SCA3300_RS_ERROR) > > > >>>>>> + return rs; > > > >>>>>> + > > > >>>>>> + *val = (s16)(sca_data->rxbuf[2] | (sca_data->rxbuf[1] << 8)); > > > >>>>> Preference for an unaligned endian conversion here and explicit sign > > > >>>>> extend e.g > > > >>>>> something like > > > >>>>> > > > >>>>> sign_extend32(get_unaligned_le16(&sca_data->rxbuf[1]), 15) > > > >>>>> > > > >>>>>> + > > > >>>>>> + return 0; > > > >>>>>> +} > > > >>>>>> + > > > >>>>>> +static int sca3300_read_reg(struct sca3300_data *sca_data, u8 reg, > > > >>>>>> int *val) > > > >>>>>> +{ > > > >>>>>> + int ret; > > > >>>>>> + > > > >>>>>> + mutex_lock(&sca_data->lock); > > > >>>>>> + sca_data->txbuf[0] = SCA3300_X_READ | (reg << 2); > > > >>>>>> + ret = sca3300_transfer(sca_data, val); > > > >>>>>> + if (ret > 0) { > > > >>>>>> + sca_data->txbuf[0] = SCA3300_X_READ | (SCA3300_REG_STATUS > > > >>>>>> << 2); > > > >>>>>> + ret = sca3300_transfer(sca_data, val); > > > >>>>>> + /* status 0 = startup, 0x2 = mode change */ > > > >>>>>> + if (ret > 0 && *val != 0 && *val != 0x2) { > > > >>>>>> + dev_err_ratelimited(&sca_data->spi->dev, > > > >>>>>> + "device status: %x\n", > > > >>>>>> + (u16)*val); > > > >>>>>> + mutex_unlock(&sca_data->lock); > > > >>>>>> + return -EIO; > > > >>>>>> + } > > > >>>>>> + if (ret > 0) > > > >>>>>> + ret = 0; > > > >>>>>> + } > > > >>>>>> + mutex_unlock(&sca_data->lock); > > > >>>>>> + > > > >>>>>> + return ret; > > > >>>>>> +} > > > >>>>>> + > > > >>>>>> +static int sca3300_write_reg(struct sca3300_data *sca_data, u8 > > > >>>>>> reg, int val) > > > >>>>>> +{ > > > >>>>>> + int reg_val = 0; > > > >>>>>> + int ret; > > > >>>>>> + > > > >>>>>> + mutex_lock(&sca_data->lock); > > > >>>>>> + sca_data->txbuf[0] = SCA3300_X_WRITE | (reg << 2); > > > >>>>>> + sca_data->txbuf[1] = val >> 8; > > > >>>>>> + sca_data->txbuf[2] = val & 0xFF; > > > >>>>> Prefer (Slightly) an unaligned put. > > > >>>>> > > > >>>>>> + ret = sca3300_transfer(sca_data, ®_val); > > > >>>>>> + if (ret > 0) { > > > >>>>> Factor this error handling out to another function, plus trigger it > > > >>>>> from an > > > >>>>> appropriate standard error code rather than a positive return value. > > > >>>>> > > > >>>>>> + sca_data->txbuf[0] = SCA3300_X_READ | (SCA3300_REG_STATUS > > > >>>>>> << 2); > > > >>>>>> + ret = sca3300_transfer(sca_data, ®_val); > > > >>>>>> + /* status 0 = startup, 0x2 = mode change */ > > > >>>>>> + if (ret > 0 && reg_val != 0 && reg_val != 0x2) { > > > >>>>>> + dev_err_ratelimited(&sca_data->spi->dev, > > > >>>>>> + "device status: %x\n", > > > >>>>>> + (u16)reg_val); > > > >>>>>> + mutex_unlock(&sca_data->lock); > > > >>>>>> + return -EIO; > > > >>>>>> + } > > > >>>>>> + if (ret > 0) > > > >>>>>> + ret = 0; > > > >>>>> Whenever you get this sort of juggling it rather implies your design is > > > >>>>> less than ideal. > > > >>>>> > > > >>>>>> + } > > > >>>>>> + mutex_unlock(&sca_data->lock); > > > >>>>>> + > > > >>>>>> + return ret; > > > >>>>>> +} > > > >>>>>> + > > > >>>>>> +static int sca3300_write_raw(struct iio_dev *indio_dev, > > > >>>>>> + struct iio_chan_spec const *chan, > > > >>>>>> + int val, int val2, long mask) > > > >>>>>> +{ > > > >>>>>> + struct sca3300_data *data = iio_priv(indio_dev); > > > >>>>>> + > > > >>>>>> + switch (mask) { > > > >>>>>> + case IIO_CHAN_INFO_SCALE: > > > >>>>>> + if (val < 0 || val > 3) > > > >>>>>> + return -EINVAL; > > > >>>>> No. Scale values need to be the value of 1LSB not a random integer > > > >>>>> that requires you to look up the datasheet. > > > >>>>> > > > >>>>>> + return sca3300_write_reg(data, SCA3300_REG_MODE, val); > > > >>>>>> + default: > > > >>>>>> + return -EINVAL; > > > >>>>>> + } > > > >>>>>> +} > > > >>>>>> + > > > >>>>>> +static int sca3300_read_raw(struct iio_dev *indio_dev, > > > >>>>>> + struct iio_chan_spec const *chan, > > > >>>>>> + int *val, int *val2, long mask) > > > >>>>>> +{ > > > >>>>>> + struct sca3300_data *data = iio_priv(indio_dev); > > > >>>>>> + int ret; > > > >>>>>> + int reg_val; > > > >>>>>> + > > > >>>>>> + switch (mask) { > > > >>>>>> + case IIO_CHAN_INFO_RAW: > > > >>>>>> + ret = sca3300_read_reg(data, chan->address, val); > > > >>>>>> + if (ret < 0) > > > >>>>>> + return ret; > > > >>>>>> + return IIO_VAL_INT; > > > >>>>>> + case IIO_CHAN_INFO_SCALE: > > > >>>>>> + ret = sca3300_read_reg(data, SCA3300_REG_MODE, ®_val); > > > >>>>>> + if (ret < 0) > > > >>>>>> + return ret; > > > >>>>>> + *val = sca3300_accel_scale[reg_val]; > > > >>>>> Scale is very very rarely an integer value which makes me wonder what > > > >>>>> you are returning here... It should be the multiplier needed to > > > >>>>> take the raw value to a reading in m/sec^2 Given you use it as > > > >>>>> fractional > > > >>>>> below, I'm guessing this is 1/scale_value? > > > >>>>> > > > >>>>>> + return IIO_VAL_INT; > > > >>>>>> + case IIO_CHAN_INFO_PROCESSED: > > > >>>>> Don't provide processed here. Userspace needs to do the conversion > > > >>>>> itself > > > >>>>> (and given it has floating point easily available will probably do a > > > >>>>> better > > > >>>>> job than we can). I'm assuming the mode can't autonomously change? > > > >>>>> > > > >>>>>> + ret = sca3300_read_reg(data, SCA3300_REG_MODE, ®_val); > > > >>>>>> + if (ret < 0) > > > >>>>>> + return ret; > > > >>>>>> + *val2 = sca3300_accel_scale[reg_val]; > > > >>>>>> + ret = sca3300_read_reg(data, chan->address, val); > > > >>>>>> + if (ret < 0) > > > >>>>>> + return ret; > > > >>>>>> + return IIO_VAL_FRACTIONAL; > > > >>>>>> + default: > > > >>>>>> + return -EINVAL; > > > >>>>>> + } > > > >>>>>> +} > > > >>>>>> + > > > >>>>>> +static irqreturn_t sca3300_trigger_handler(int irq, void *p) > > > >>>>>> +{ > > > >>>>>> + struct iio_poll_func *pf = p; > > > >>>>>> + struct iio_dev *indio_dev = pf->indio_dev; > > > >>>>>> + struct sca3300_data *data = iio_priv(indio_dev); > > > >>>>>> + s64 time_ns = iio_get_time_ns(indio_dev); > > > >>>>> Is the timestamp at the start more accurate that that at the end > > > >>>>> of reading the channels? If not, just put this inline in the > > > >>>>> iio_push_to_buffers_with_timestamp() call. > > > >>>>> > > > >>>>>> + int bit, ret, val, i = 0; > > > >>>>>> + > > > >>>>>> + for_each_set_bit(bit, indio_dev->active_scan_mask, > > > >>>>>> + indio_dev->masklength) { > > > >>>>>> + ret = sca3300_read_reg(data, sca3300_channels[bit].address, > > > >>>>>> + &val); > > > >>>>>> + if (ret < 0) > > > >>>>> Given we can't return an error code from interrupt handlers, it is > > > >>>>> usually > > > >>>>> a good idea to print something to the log. Otherwise we get missing > > > >>>>> data > > > >>>>> with no idea of why.. > > > >>>>> > > > >>>>>> + goto out; > > > >>>>>> + if (ARRAY_SIZE(data->scan.channels) > i) > > > >>>>> How could this not be true? If it's always true, don't bother > > > >>>>> checking i. > > > >>>>> > > > >>>>>> + ((s16 *)data->scan.channels)[i++] = val; > > > >>>>>> + } > > > >>>>>> + > > > >>>>>> + iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, > > > >>>>>> time_ns); > > > >>>>>> +out: > > > >>>>>> + iio_trigger_notify_done(indio_dev->trig); > > > >>>>>> + > > > >>>>>> + return IRQ_HANDLED; > > > >>>>>> +} > > > >>>>>> + > > > >>>>>> +static int sca3300_init(struct sca3300_data *sca_data, > > > >>>>>> + struct iio_dev *indio_dev) > > > >>>>>> +{ > > > >>>>>> + int ret; > > > >>>>>> + int value = 0; > > > >>>>>> + > > > >>>>>> + if (sca_data->opmode < 1 || sca_data->opmode > 4) > > > >>>>>> + return -EINVAL; > > > >>>>> Whilst this is going anyway, better to check that next to where > > > >>>>> it is read so we drop out immediately rather than buried in this > > > >>>>> function. > > > >>>>> > > > >>>>>> + > > > >>>>>> + ret = sca3300_write_reg(sca_data, SCA3300_REG_MODE, > > > >>>>>> + SCA3300_VALUE_SW_RESET); > > > >>>>>> + if (ret != 0) > > > >>>>>> + return ret; > > > >>>>> For sleeps, good to reference which section in data sheet gives the > > > >>>>> timing. > > > >>>>> > > > >>>>>> + usleep_range(2e3, 10e3); > > > >>>>>> + > > > >>>>>> + ret = sca3300_write_reg(sca_data, SCA3300_REG_MODE, > > > >>>>>> + sca_data->opmode - 1); > > > >>>>>> + if (ret != 0) > > > >>>>> if (ret) see below. > > > >>>>> > > > >>>>>> + return ret; > > > >>>>>> + msleep(100); > > > >>>>> Again, document where the time comes from. Saves reviewers time if > > > >>>>> they want to check it. (I'm too lazy :) > > > >>>>> > > > >>>>>> + ret = sca3300_read_reg(sca_data, SCA3300_REG_WHOAMI, &value); > > > >>>>>> + if (ret != 0) > > > >>>>> if (ret) is more idiomatic in kernel code. > > > >>>>> > > > >>>>>> + return ret; > > > >>>>>> + > > > >>>>>> + if (value != SCA3300_DEVICE_ID) { > > > >>>>>> + dev_err(&sca_data->spi->dev, "device id not expected > > > >>>>>> value\n"); > > > >>>>> Perhaps useful to print what was expected and what was seen. Maybe it's > > > >>>>> a new variant and this might help the user to identify that and add > > > >>>>> it to the > > > >>>>> driver. > > > >>>>> > > > >>>>>> + return -EIO; > > > >>>>> -EINVAL probably more appropriate return. > > > >>>>> > > > >>>>>> + } > > > >>>>>> + return 0; > > > >>>>>> +} > > > >>>>>> + > > > >>>>>> +static int sca3300_debugfs_reg_access(struct iio_dev *indio_dev, > > > >>>>>> + unsigned int reg, unsigned int writeval, > > > >>>>>> + unsigned int *readval) > > > >>>>>> +{ > > > >>>>>> + struct sca3300_data *data = iio_priv(indio_dev); > > > >>>>>> + int value; > > > >>>>>> + int ret; > > > >>>>>> + > > > >>>>>> + if (reg > 0x1f) > > > >>>>> Use a define that names that register. > > > >>>>> > > > >>>>>> + return -EINVAL; > > > >>>>>> + > > > >>>>>> + if (!readval) > > > >>>>>> + return sca3300_write_reg(data, reg, writeval); > > > >>>>>> + > > > >>>>>> + ret = sca3300_read_reg(data, reg, &value); > > > >>>>>> + if (ret < 0) > > > >>>>>> + return ret; > > > >>>>>> + > > > >>>>>> + *readval = (unsigned int)value; > > > >>>>>> + > > > >>>>>> + return 0; > > > >>>>>> +} > > > >>>>>> + > > > >>>>>> +static const struct iio_info sca3300_info = { > > > >>>>>> + .read_raw = sca3300_read_raw, > > > >>>>>> + .write_raw = sca3300_write_raw, > > > >>>>>> + .debugfs_reg_access = &sca3300_debugfs_reg_access, > > > >>>>>> +}; > > > >>>>>> + > > > >>>>>> +static int sca3300_probe(struct spi_device *spi) > > > >>>>>> +{ > > > >>>>>> + struct sca3300_data *sca_data; > > > >>>>>> + struct iio_dev *indio_dev; > > > >>>>>> + int ret; > > > >>>>>> + > > > >>>>>> + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*sca_data)); > > > >>>>>> + if (!indio_dev) { > > > >>>>>> + dev_err(&spi->dev, > > > >>>>>> + "failed to allocate memory for iio device\n"); > > > >>>>>> + return -ENOMEM; > > > >>>>>> + } > > > >>>>>> + > > > >>>>>> + sca_data = iio_priv(indio_dev); > > > >>>>>> + mutex_init(&sca_data->lock); > > > >>>>>> + sca_data->spi = spi; > > > >>>>>> + spi_set_drvdata(spi, indio_dev); > > > >>>>> Won't be used once using devm as below and remove() is dropped, so > > > >>>>> drop this. > > > >>>>> > > > >>>>>> + > > > >>>>>> + crc8_populate_msb(sca3300_crc_table, SCA3300_CRC8_POLYNOMIAL); > > > >>>>>> + > > > >>>>>> + indio_dev->dev.parent = &spi->dev; > > > >>>>>> + indio_dev->info = &sca3300_info; > > > >>>>>> + indio_dev->name = SCA3300_ALIAS; > > > >>>>>> + indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_TRIGGERED; > > > >>>>> BUFFER_TRIGGERED bit now set by iio_triggered_buffer_setup() so > > > >>>>> shouldn't > > > >>>>> be ehre as well. > > > >>>>> > > > >>>>>> + indio_dev->channels = sca3300_channels; > > > >>>>>> + indio_dev->num_channels = ARRAY_SIZE(sca3300_channels); > > > >>>>>> + indio_dev->available_scan_masks = sca3300_scan_masks; > > > >>>>>> + > > > >>>>>> + if (spi->dev.of_node) { > > > >>>>>> + ret = of_property_read_u32(spi->dev.of_node, "murata,opmode", > > > >>>>> Please use generic firmware access calls rather than the of specific > > > >>>>> ones. > > > >>>>> That lets us get ACPI support for free :) > > > >>>>> > > > >>>>> As per the binding review however, this one needs to go in favour of > > > >>>>> userspace > > > >>>>> control of scale + filter frequencies / sampling freq. > > > >>>>> > > > >>>>>> + &sca_data->opmode); > > > >>>>>> + if (ret < 0) > > > >>>>>> + return ret; > > > >>>>>> + } > > > >>>>>> + > > > >>>>>> + ret = sca3300_init(sca_data, indio_dev); > > > >>>>>> + if (ret < 0) { > > > >>>>>> + dev_err(&spi->dev, "failed to init device, error: %d\n", > > > >>>>>> ret); > > > >>>>>> + return ret; > > > >>>>>> + } > > > >>>>>> + > > > >>>>>> + ret = iio_triggered_buffer_setup(indio_dev, > > > >>>>>> iio_pollfunc_store_time, > > > >>>>>> + sca3300_trigger_handler, NULL); > > > >>>>> devm_iio_triggered_buffer_setup() and you can drop the manual > > > >>>>> cleanup in remove() > > > >>>>> and hence drop remove() entirely as nothing else left. > > > >>>>> > > > >>>>>> + if (ret < 0) { > > > >>>>>> + dev_err(&spi->dev, > > > >>>>>> + "iio triggered buffer setup failed, error: %d\n", ret); > > > >>>>>> + return ret; > > > >>>>>> + } > > > >>>>>> + > > > >>>>>> + ret = devm_iio_device_register(&spi->dev, indio_dev); > > > >>>>>> + if (ret < 0) { > > > >>>>>> + dev_err(&spi->dev, "iio device register failed, error: %d\n", > > > >>>>>> + ret); > > > >>>>>> + iio_triggered_buffer_cleanup(indio_dev); > > > >>>>> With devm above, no need to manually clean this up. > > > >>>>> > > > >>>>>> + return ret; > > > >>>>>> + } > > > >>>>>> + > > > >>>>>> + return 0; > > > >>>>>> +} > > > >>>>>> + > > > >>>>>> +static int sca3300_remove(struct spi_device *spi) > > > >>>>>> +{ > > > >>>>>> + struct iio_dev *indio_dev = spi_get_drvdata(spi); > > > >>>>>> + > > > >>>>>> + iio_triggered_buffer_cleanup(indio_dev); > > > >>>>>> + return 0; > > > >>>>>> +} > > > >>>>>> + > > > >>>>>> +static const struct of_device_id sca3300_dt_ids[] = { > > > >>>>>> + { .compatible = "murata,sca3300"}, > > > >>>>>> + {}, > > > >>>>>> +}; > > > >>>>>> +MODULE_DEVICE_TABLE(of, sca3300_dt_ids); > > > >>>>>> + > > > >>>>>> +static struct spi_driver sca3300_driver = { > > > >>>>>> + .driver = { > > > >>>>>> + .name = SCA3300_ALIAS, > > > >>>>>> + .owner = THIS_MODULE, > > > >>>>>> + .of_match_table = of_match_ptr(sca3300_dt_ids), > > > >>>>>> + }, > > > >>>>>> + > > > >>>>>> + .probe = sca3300_probe, > > > >>>>>> + .remove = sca3300_remove, > > > >>>>>> +}; > > > >>>>>> + > > > >>>>>> +module_spi_driver(sca3300_driver); > > > >>>>>> + > > > >>>>>> +MODULE_AUTHOR("Tomas Melin "); > > > >>>>>> +MODULE_DESCRIPTION("Murata SCA3300 SPI Accelerometer"); > > > >>>>>> +MODULE_LICENSE("GPL v2"); > > >