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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 93B42C432C3 for ; Thu, 14 Nov 2019 18:18:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 50FC620729 for ; Thu, 14 Nov 2019 18:18:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="CIC4+e6b" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726812AbfKNSSS (ORCPT ); Thu, 14 Nov 2019 13:18:18 -0500 Received: from mail-io1-f68.google.com ([209.85.166.68]:36054 "EHLO mail-io1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727466AbfKNSSF (ORCPT ); Thu, 14 Nov 2019 13:18:05 -0500 Received: by mail-io1-f68.google.com with SMTP id s3so7893297ioe.3 for ; Thu, 14 Nov 2019 10:18:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=KAAWJfeRSS1d+sQ4mP+lqoxBYirPVRmLcoL2PNH5oVA=; b=CIC4+e6b4yzUkYSER9FF/me4BYfzbYL9ITgAmTCmusFV3KQ9VA+L2LeZ/N9mujPpKp ynXMrBHWby8REWve9JmM4u2eCQn+onXzU0SAlzbeM560L/7D5qI9h9BDHlv0fEASI5E2 NxWbxx3iS9WgqJTJeBZ3FsoWgDgInhjDbR6Xw= 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=KAAWJfeRSS1d+sQ4mP+lqoxBYirPVRmLcoL2PNH5oVA=; b=P46Rq2WwD2ulmDAq9fP09i9bbpWOIT5g4J4DzCDvqvxHMseI6lvcGb/DItq2mLQdf2 tywkecGbzWzAB3B2nBpGdgryTor+NqiGeqCHrCk2rKNO+g5KoPxMyeRX1FekQd4O3YOR /IwgCLwVu1MpwmAkkyaXiogzW7turjdY4jQrlfTlJ+A0E2HOpWG/NzSz4KAyUgyZNgdc Knq0iko1c3LYYmJXap0jyZmP6l6ifK5ckKwAWQM1vtjzxptfDQdkAeScVl2isxpS4IV2 rqa7md6M2mXfuO7uZqogpdbmaqoMhZI3VbIy+W09gCeHE0Or4tD4oD2PUpk8DwAlD+cv L4tw== X-Gm-Message-State: APjAAAWRR8FHn7+4YSTsrUX8oOCbjVtqiEkT6iwwRpaP7cjrgdW/kJpW X3hPAMBmfhXF30tEtSL78ZPsXqRoKCgN01dkOTaCEw== X-Google-Smtp-Source: APXvYqxsqRoHtcWRn7wtm1cdL7W2E9Rrd56ksQa0QocNyLEJNjeX6uk7PKGRDnAly0ZgiPLnK2lAL+45gREQ6YMKrQI= X-Received: by 2002:a05:6638:237:: with SMTP id f23mr8838217jaq.51.1573755483431; Thu, 14 Nov 2019 10:18:03 -0800 (PST) MIME-Version: 1.0 References: <20191105222652.70226-1-gwendal@chromium.org> <20191105222652.70226-14-gwendal@chromium.org> <20191110131714.098ee2ea@archlinux> In-Reply-To: <20191110131714.098ee2ea@archlinux> From: Gwendal Grignou Date: Thu, 14 Nov 2019 10:17:52 -0800 Message-ID: Subject: Re: [PATCH v4 13/17] iio: cros_ec: Register to cros_ec_sensorhub when EC supports FIFO To: Jonathan Cameron Cc: Brian Norris , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Lee Jones , Benson Leung , Enric Balletbo i Serra , Doug Anderson , Guenter Roeck , Fabien Lahoudere , linux-kernel , linux-iio Content-Type: text/plain; charset="UTF-8" Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org The problem are:- in case of a kernel crash while collecting sensor data: when the kernel restart, the sensors are still sending events. - we can also enable a sensor behind the iiio driver back through debug tools: we don On Sun, Nov 10, 2019 at 5:17 AM Jonathan Cameron wrote: > > On Tue, 5 Nov 2019 14:26:48 -0800 > Gwendal Grignou wrote: > > > When EC supports FIFO, each IIO device registers a callback, to put > > samples in the buffer when they arrives from the FIFO. > > We can still use a trigger to collect samples, but there may be some > > duplications in the buffer: EC has a single FIFO, so once one sensor is > > using it, all sensors event will be in the FIFO. > > To be sure events generated by cros_ec_sensorhub or the trigger uses the > > same time domain, current_timestamp_clock must be set to "boottime". > > How is that enforced? I should have removed this comment: cros_ec_sensors_push_data() now checks for the iio dev clock_id and add an offset if necessary. I add a patch for IIO to allow changing timestamp_clock from the driver itself: I set to default for cros ec sensor to boottime, since it is the default timestamp source coming from the FIFO. > I'd have no problem with core support for IIO > to allow a driver that has requirements like this to override > the normal flexibility. > > > > > When no FIFO, the user space app needs to call trigger_new, or better > > register a high precision timer. > > > > Signed-off-by: Gwendal Grignou > A question + a comment that I'm still not happy with the fact we have > to protect against a race on startup. However, we can perhaps make that > a problem for another day. > > Assuming the question on the mode mask change is resolved. > Reviewed-by: Jonathan Cameron > > > --- > > Changes in v4: > > - Fix a logic error when the sensor is not "physical", for instance lig > > angle: core_init() would return !0 even if there was no error. > > - Check patch with --strict option > > Use sizeof(*obj) instead of sizeof(struct ...obj) > > Alignement > > Change in v3: > > - Remove double line > > - Fix indentation > > - Add code to support iio clock_id setting. Optimized for > > CLOCK_BOOTTIME. > > Change in v2 from "Use triggered buffer only when EC does not support > > FIFO": > > - Keep trigger all the time. > > - Add devm_add_action to cleanup callback registration. > > - EC that "reports" legacy sensors do not have FIFO. > > - Use iiio_is_buffer_enabled instead of checking the scan_mask > > before sending samples to buffer. > > - Add empty lines for visibility. > > > > drivers/iio/accel/cros_ec_accel_legacy.c | 8 +- > > .../cros_ec_sensors/cros_ec_lid_angle.c | 2 +- > > .../common/cros_ec_sensors/cros_ec_sensors.c | 9 +- > > .../cros_ec_sensors/cros_ec_sensors_core.c | 85 ++++++++++++++++++- > > drivers/iio/light/cros_ec_light_prox.c | 9 +- > > drivers/iio/pressure/cros_ec_baro.c | 9 +- > > .../linux/iio/common/cros_ec_sensors_core.h | 10 ++- > > 7 files changed, 103 insertions(+), 29 deletions(-) > > > > diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c > > index 65f85faf6f31..b9f651e4ce99 100644 > > --- a/drivers/iio/accel/cros_ec_accel_legacy.c > > +++ b/drivers/iio/accel/cros_ec_accel_legacy.c > > @@ -171,7 +171,8 @@ static int cros_ec_accel_legacy_probe(struct platform_device *pdev) > > if (!indio_dev) > > return -ENOMEM; > > > > - ret = cros_ec_sensors_core_init(pdev, indio_dev, true); > > + ret = cros_ec_sensors_core_init(pdev, indio_dev, true, > > + cros_ec_sensors_capture, NULL); > > if (ret) > > return ret; > > > > @@ -191,11 +192,6 @@ static int cros_ec_accel_legacy_probe(struct platform_device *pdev) > > state->sign[CROS_EC_SENSOR_Z] = -1; > > } > > > > - ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, > > - cros_ec_sensors_capture, NULL); > > - if (ret) > > - return ret; > > - > > return devm_iio_device_register(dev, indio_dev); > > } > > > > diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_lid_angle.c b/drivers/iio/common/cros_ec_sensors/cros_ec_lid_angle.c > > index 1dcc2a16ab2d..e30a59fcf0f9 100644 > > --- a/drivers/iio/common/cros_ec_sensors/cros_ec_lid_angle.c > > +++ b/drivers/iio/common/cros_ec_sensors/cros_ec_lid_angle.c > > @@ -97,7 +97,7 @@ static int cros_ec_lid_angle_probe(struct platform_device *pdev) > > if (!indio_dev) > > return -ENOMEM; > > > > - ret = cros_ec_sensors_core_init(pdev, indio_dev, false); > > + ret = cros_ec_sensors_core_init(pdev, indio_dev, false, NULL, NULL); > > if (ret) > > return ret; > > > > diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c > > index 7dce04473467..62a0dd970988 100644 > > --- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c > > +++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c > > @@ -231,7 +231,9 @@ static int cros_ec_sensors_probe(struct platform_device *pdev) > > if (!indio_dev) > > return -ENOMEM; > > > > - ret = cros_ec_sensors_core_init(pdev, indio_dev, true); > > + ret = cros_ec_sensors_core_init(pdev, indio_dev, true, > > + cros_ec_sensors_capture, > > + cros_ec_sensors_push_data); > > if (ret) > > return ret; > > > > @@ -293,11 +295,6 @@ static int cros_ec_sensors_probe(struct platform_device *pdev) > > else > > state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd; > > > > - ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, > > - cros_ec_sensors_capture, NULL); > > - if (ret) > > - return ret; > > - > > return devm_iio_device_register(dev, indio_dev); > > } > > > > diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c > > index b47da497a3c3..904cd26dd31f 100644 > > --- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c > > +++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c > > @@ -12,6 +12,7 @@ > > #include > > #include > > #include > > +#include > > #include > > #include > > #include > > @@ -83,17 +84,78 @@ static void get_default_min_max_freq(enum motionsensor_type type, > > } > > } > > > > +int cros_ec_sensors_push_data(struct iio_dev *indio_dev, > > + s16 *data, > > + s64 timestamp) > > +{ > > + struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); > > + s16 *out; > > + s64 delta; > > + unsigned int i; > > + > > + /* > > + * It can happen if we get a samples before the iio device is fully > > + * registered. > > I'd really like to stop that happening as it seems like a nasty racey corner case. > I'm not convinced there aren't 'half registered' cases we can still hit even > with this protection. Hardware should be in a clean state before any > interrupts etc are registered. You're right, st can not be null, since devm_iio_device_alloc is called before cros_ec_sensors_core_init that register the callback. > > However if you are sure this protection is enough that can be a job for another day. > > I suspect you get away with it because of the next check always failing in > those racey conditions as can't enable the buffer until we have a fully > set up device. > > > + */ > > + if (!st) > > + return 0; > > + > > + /* > > + * Ignore samples if the buffer is not set: it is needed if the ODR is > > + * set but the buffer is not enabled yet. > > + */ > > + if (!iio_buffer_enabled(indio_dev)) > > + return 0; This check is necessary: - in case of a kernel crash while collecting sensor data: when the kernel restart, the sensors are still sending events. - we can also enable a sensor behind the iiio driver back through debug tools: the sensor will send sample, but the iio driver is not ready for them. > > + > > + out = (s16 *)st->samples; > > + for_each_set_bit(i, > > + indio_dev->active_scan_mask, > > + indio_dev->masklength) { > > + *out = data[i]; > > + out++; > > + } > > + > > + if (iio_device_get_clock(indio_dev) != CLOCK_BOOTTIME) > > + delta = iio_get_time_ns(indio_dev) - cros_ec_get_time_ns(); > > + else > > + delta = 0; > > + > > + iio_push_to_buffers_with_timestamp(indio_dev, st->samples, > > + timestamp + delta); > > + > > + return 0; > > +} > > +EXPORT_SYMBOL_GPL(cros_ec_sensors_push_data); > > + > > +static void cros_ec_sensors_core_clean(void *arg) > > +{ > > + struct platform_device *pdev = (struct platform_device *)arg; > > + struct cros_ec_sensorhub *sensor_hub = > > + dev_get_drvdata(pdev->dev.parent); > > + struct iio_dev *indio_dev = platform_get_drvdata(pdev); > > + struct cros_ec_sensors_core_state *st = iio_priv(indio_dev); > > + u8 sensor_num = st->param.info.sensor_num; > > + > > + cros_ec_sensorhub_unregister_push_data(sensor_hub, sensor_num); > > +} > > + > > /** > > * cros_ec_sensors_core_init() - basic initialization of the core structure > > * @pdev: platform device created for the sensors > > * @indio_dev: iio device structure of the device > > * @physical_device: true if the device refers to a physical device > > + * @trigger_capture: function pointer to call buffer is triggered, > > + * for backward compatibility. > > + * @push_data: function to call when cros_ec_sensorhub receives > > + * a sample for that sensor. > > * > > * Return: 0 on success, -errno on failure. > > */ > > int cros_ec_sensors_core_init(struct platform_device *pdev, > > struct iio_dev *indio_dev, > > - bool physical_device) > > + bool physical_device, > > + cros_ec_sensors_capture_t trigger_capture, > > + cros_ec_sensorhub_push_data_cb_t push_data) > > { > > struct device *dev = &pdev->dev; > > struct cros_ec_sensors_core_state *state = iio_priv(indio_dev); > > @@ -132,8 +194,6 @@ int cros_ec_sensors_core_init(struct platform_device *pdev, > > indio_dev->name = pdev->name; > > > > if (physical_device) { > > - indio_dev->modes = INDIO_DIRECT_MODE; > > - > > This particular changes seems odd. Are we dropping access via sysfs? > From what I recall we don't actually do much with this currently in the > IIO core, but we 'might' in future ;) Should not have been removed. > > > state->param.cmd = MOTIONSENSE_CMD_INFO; > > state->param.info.sensor_num = sensor_platform->sensor_num; > > ret = cros_ec_motion_send_host_cmd(state, 0); > > @@ -162,6 +222,25 @@ int cros_ec_sensors_core_init(struct platform_device *pdev, > > state->frequencies[2] = > > state->resp->info_3.max_frequency; > > } > > + > > + ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, > > + trigger_capture, NULL); > > + if (ret) > > + return ret; > > + > > + if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) { > > + ret = cros_ec_sensorhub_register_push_data(sensor_hub, > > + sensor_platform->sensor_num, > > + indio_dev, push_data); > > + if (ret) > > + return ret; > > + > > + ret = devm_add_action_or_reset(dev, > > + cros_ec_sensors_core_clean, > > + pdev); > > + if (ret) > > + return ret; > > + } > > } > > > > return 0; > > diff --git a/drivers/iio/light/cros_ec_light_prox.c b/drivers/iio/light/cros_ec_light_prox.c > > index d85a391e50c5..698b2ee81ebf 100644 > > --- a/drivers/iio/light/cros_ec_light_prox.c > > +++ b/drivers/iio/light/cros_ec_light_prox.c > > @@ -178,7 +178,9 @@ static int cros_ec_light_prox_probe(struct platform_device *pdev) > > if (!indio_dev) > > return -ENOMEM; > > > > - ret = cros_ec_sensors_core_init(pdev, indio_dev, true); > > + ret = cros_ec_sensors_core_init(pdev, indio_dev, true, > > + cros_ec_sensors_capture, > > + cros_ec_sensors_push_data); > > if (ret) > > return ret; > > > > @@ -237,11 +239,6 @@ static int cros_ec_light_prox_probe(struct platform_device *pdev) > > > > state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd; > > > > - ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, > > - cros_ec_sensors_capture, NULL); > > - if (ret) > > - return ret; > > - > > return devm_iio_device_register(dev, indio_dev); > > } > > > > diff --git a/drivers/iio/pressure/cros_ec_baro.c b/drivers/iio/pressure/cros_ec_baro.c > > index 2354302375de..e1c86b22676c 100644 > > --- a/drivers/iio/pressure/cros_ec_baro.c > > +++ b/drivers/iio/pressure/cros_ec_baro.c > > @@ -134,7 +134,9 @@ static int cros_ec_baro_probe(struct platform_device *pdev) > > if (!indio_dev) > > return -ENOMEM; > > > > - ret = cros_ec_sensors_core_init(pdev, indio_dev, true); > > + ret = cros_ec_sensors_core_init(pdev, indio_dev, true, > > + cros_ec_sensors_capture, > > + cros_ec_sensors_push_data); > > if (ret) > > return ret; > > > > @@ -180,11 +182,6 @@ static int cros_ec_baro_probe(struct platform_device *pdev) > > > > state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd; > > > > - ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, > > - cros_ec_sensors_capture, NULL); > > - if (ret) > > - return ret; > > - > > return devm_iio_device_register(dev, indio_dev); > > } > > > > diff --git a/include/linux/iio/common/cros_ec_sensors_core.h b/include/linux/iio/common/cros_ec_sensors_core.h > > index 0af918978f97..b8f573ca9dcc 100644 > > --- a/include/linux/iio/common/cros_ec_sensors_core.h > > +++ b/include/linux/iio/common/cros_ec_sensors_core.h > > @@ -12,6 +12,7 @@ > > #include > > #include > > #include > > +#include > > > > enum { > > CROS_EC_SENSOR_X, > > @@ -32,6 +33,8 @@ enum { > > /* Minimum sampling period to use when device is suspending */ > > #define CROS_EC_MIN_SUSPEND_SAMPLING_FREQUENCY 1000 /* 1 second */ > > > > +typedef irqreturn_t (*cros_ec_sensors_capture_t)(int irq, void *p); > > + > > /** > > * struct cros_ec_sensors_core_state - state data for EC sensors IIO driver > > * @ec: cros EC device structure > > @@ -87,9 +90,14 @@ int cros_ec_sensors_read_cmd(struct iio_dev *indio_dev, unsigned long scan_mask, > > > > struct platform_device; > > int cros_ec_sensors_core_init(struct platform_device *pdev, > > - struct iio_dev *indio_dev, bool physical_device); > > + struct iio_dev *indio_dev, bool physical_device, > > + cros_ec_sensors_capture_t trigger_capture, > > + cros_ec_sensorhub_push_data_cb_t push_data); > > > > irqreturn_t cros_ec_sensors_capture(int irq, void *p); > > +int cros_ec_sensors_push_data(struct iio_dev *indio_dev, > > + s16 *data, > > + s64 timestamp); > > > > int cros_ec_motion_send_host_cmd(struct cros_ec_sensors_core_state *st, > > u16 opt_length); >