From ec2daf6e33f9f9113ba085b6ff88592907b6f1ce Mon Sep 17 00:00:00 2001 From: Jon Flatley Date: Fri, 24 Jan 2020 15:18:32 -0800 Subject: platform: chrome: Add cros-usbpd-notify driver ChromiumOS uses ACPI device with HID "GOOG0003" for power delivery related events. The existing cros-usbpd-charger driver relies on these events without ever actually receiving them on ACPI platforms. This is because in the ChromeOS kernel trees, the GOOG0003 device is owned by an ACPI driver that offers firmware updates to USB-C chargers. Introduce a new platform driver under cros-ec, the ChromeOS embedded controller, that handles these PD events and dispatches them appropriately over a notifier chain to all drivers that use them. On platforms that don't have the ACPI device defined, the driver gets instantiated for ECs which support the EC_FEATURE_USB_PD feature bit, and the notification events will get delivered using the MKBP event handling mechanism. Co-Developed-by: Prashant Malani Reviewed-by: Gwendal Grignou Reviewed-by: Benson Leung Signed-off-by: Jon Flatley Signed-off-by: Prashant Malani Acked-By: Enric Balletbo i Serra Signed-off-by: Benson Leung --- include/linux/platform_data/cros_usbpd_notify.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) create mode 100644 include/linux/platform_data/cros_usbpd_notify.h (limited to 'include/linux/platform_data') diff --git a/include/linux/platform_data/cros_usbpd_notify.h b/include/linux/platform_data/cros_usbpd_notify.h new file mode 100644 index 000000000000..4f2791722b6d --- /dev/null +++ b/include/linux/platform_data/cros_usbpd_notify.h @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ChromeOS EC Power Delivery Notifier Driver + * + * Copyright 2020 Google LLC + */ + +#ifndef __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H +#define __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H + +#include + +int cros_usbpd_register_notify(struct notifier_block *nb); + +void cros_usbpd_unregister_notify(struct notifier_block *nb); + +#endif /* __LINUX_PLATFORM_DATA_CROS_USBPD_NOTIFY_H */ -- cgit From 8673e944b50ec6e5afd4f599cf12b2798b629f3d Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Wed, 5 Feb 2020 11:48:28 +0200 Subject: platform/chrome: wilco_ec: Platform data shouldn't include kernel.h Replace with appropriate types.h. Also there is no need to include device.h, but mutex.h. For the pointers to unknown structures use forward declarations. In the *.c files we need to include all headers that provide APIs being used in the module. Signed-off-by: Andy Shevchenko Signed-off-by: Enric Balletbo i Serra --- drivers/platform/chrome/wilco_ec/properties.c | 3 +++ drivers/platform/chrome/wilco_ec/sysfs.c | 4 ++++ include/linux/platform_data/wilco-ec.h | 8 ++++++-- 3 files changed, 13 insertions(+), 2 deletions(-) (limited to 'include/linux/platform_data') diff --git a/drivers/platform/chrome/wilco_ec/properties.c b/drivers/platform/chrome/wilco_ec/properties.c index 62f27610dd33..c2bf4c95c5d2 100644 --- a/drivers/platform/chrome/wilco_ec/properties.c +++ b/drivers/platform/chrome/wilco_ec/properties.c @@ -3,8 +3,11 @@ * Copyright 2019 Google LLC */ +#include +#include #include #include +#include #include /* Operation code; what the EC should do with the property */ diff --git a/drivers/platform/chrome/wilco_ec/sysfs.c b/drivers/platform/chrome/wilco_ec/sysfs.c index f0d174b6bb21..3c587b4054a5 100644 --- a/drivers/platform/chrome/wilco_ec/sysfs.c +++ b/drivers/platform/chrome/wilco_ec/sysfs.c @@ -8,8 +8,12 @@ * See Documentation/ABI/testing/sysfs-platform-wilco-ec for more information. */ +#include +#include #include +#include #include +#include #define CMD_KB_CMOS 0x7C #define SUB_CMD_KB_CMOS_AUTO_ON 0x03 diff --git a/include/linux/platform_data/wilco-ec.h b/include/linux/platform_data/wilco-ec.h index afede15a95bf..25f46a939637 100644 --- a/include/linux/platform_data/wilco-ec.h +++ b/include/linux/platform_data/wilco-ec.h @@ -8,8 +8,8 @@ #ifndef WILCO_EC_H #define WILCO_EC_H -#include -#include +#include +#include /* Message flags for using the mailbox() interface */ #define WILCO_EC_FLAG_NO_RESPONSE BIT(0) /* EC does not respond */ @@ -17,6 +17,10 @@ /* Normal commands have a maximum 32 bytes of data */ #define EC_MAILBOX_DATA_SIZE 32 +struct device; +struct resource; +struct platform_device; + /** * struct wilco_ec_device - Wilco Embedded Controller handle. * @dev: Device handle. -- cgit From 42cd0ab476e2daffc23982c37822a78f9a53cdd5 Mon Sep 17 00:00:00 2001 From: Yicheng Li Date: Mon, 3 Feb 2020 14:53:56 -0800 Subject: platform/chrome: cros_ec: Query EC protocol version if EC transitions between RO/RW RO and RW of EC may have different EC protocol version. If EC transitions between RO and RW, but AP does not reboot (this is true for fingerprint microcontroller / cros_fp, but not true for main ec / cros_ec), the AP still uses the protocol version queried before transition, which can cause problems. In the case of fingerprint microcontroller, this causes AP to send the wrong version of EC_CMD_GET_NEXT_EVENT to RO in the interrupt handler, which in turn prevents RO to clear the interrupt line to AP, in an infinite loop. Once an EC_HOST_EVENT_INTERFACE_READY is received, we know that there might have been a transition between RO and RW, so re-query the protocol. Signed-off-by: Yicheng Li Tested-by: Marek Szyprowski Reviewed-by: Gwendal Grignou Signed-off-by: Enric Balletbo i Serra --- drivers/platform/chrome/cros_ec.c | 30 +++++++++++++++++++++++++++++ include/linux/platform_data/cros_ec_proto.h | 4 ++++ 2 files changed, 34 insertions(+) (limited to 'include/linux/platform_data') diff --git a/drivers/platform/chrome/cros_ec.c b/drivers/platform/chrome/cros_ec.c index 6fc8f2c3ac51..7ee43b2e0654 100644 --- a/drivers/platform/chrome/cros_ec.c +++ b/drivers/platform/chrome/cros_ec.c @@ -138,6 +138,24 @@ static int cros_ec_sleep_event(struct cros_ec_device *ec_dev, u8 sleep_event) return ret; } +static int cros_ec_ready_event(struct notifier_block *nb, + unsigned long queued_during_suspend, + void *_notify) +{ + struct cros_ec_device *ec_dev = container_of(nb, struct cros_ec_device, + notifier_ready); + u32 host_event = cros_ec_get_host_event(ec_dev); + + if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_INTERFACE_READY)) { + mutex_lock(&ec_dev->lock); + cros_ec_query_all(ec_dev); + mutex_unlock(&ec_dev->lock); + return NOTIFY_OK; + } + + return NOTIFY_DONE; +} + /** * cros_ec_register() - Register a new ChromeOS EC, using the provided info. * @ec_dev: Device to register. @@ -237,6 +255,18 @@ int cros_ec_register(struct cros_ec_device *ec_dev) dev_dbg(ec_dev->dev, "Error %d clearing sleep event to ec", err); + if (ec_dev->mkbp_event_supported) { + /* + * Register the notifier for EC_HOST_EVENT_INTERFACE_READY + * event. + */ + ec_dev->notifier_ready.notifier_call = cros_ec_ready_event; + err = blocking_notifier_chain_register(&ec_dev->event_notifier, + &ec_dev->notifier_ready); + if (err) + return err; + } + dev_info(dev, "Chrome EC device registered\n"); return 0; diff --git a/include/linux/platform_data/cros_ec_proto.h b/include/linux/platform_data/cros_ec_proto.h index ba5914770191..383243326676 100644 --- a/include/linux/platform_data/cros_ec_proto.h +++ b/include/linux/platform_data/cros_ec_proto.h @@ -125,6 +125,9 @@ struct cros_ec_command { * @host_event_wake_mask: Mask of host events that cause wake from suspend. * @last_event_time: exact time from the hard irq when we got notified of * a new event. + * @notifier_ready: The notifier_block to let the kernel re-query EC + * communication protocol when the EC sends + * EC_HOST_EVENT_INTERFACE_READY. * @ec: The platform_device used by the mfd driver to interface with the * main EC. * @pd: The platform_device used by the mfd driver to interface with the @@ -166,6 +169,7 @@ struct cros_ec_device { u32 host_event_wake_mask; u32 last_resume_result; ktime_t last_event_time; + struct notifier_block notifier_ready; /* The platform devices used by the mfd driver */ struct platform_device *ec; -- cgit From cee416a347440628762db2257ff921ccf9f66923 Mon Sep 17 00:00:00 2001 From: Gwendal Grignou Date: Fri, 27 Mar 2020 15:34:32 -0700 Subject: platform/chrome: cros_ec_sensorhub: Add the number of sensors in sensorhub To better manage resources, store the number of sensors reported by the EC. Signed-off-by: Gwendal Grignou Signed-off-by: Enric Balletbo i Serra --- drivers/platform/chrome/cros_ec_sensorhub.c | 4 +++- include/linux/platform_data/cros_ec_sensorhub.h | 2 ++ 2 files changed, 5 insertions(+), 1 deletion(-) (limited to 'include/linux/platform_data') diff --git a/drivers/platform/chrome/cros_ec_sensorhub.c b/drivers/platform/chrome/cros_ec_sensorhub.c index 79fefd3bb0fa..134ee5e46047 100644 --- a/drivers/platform/chrome/cros_ec_sensorhub.c +++ b/drivers/platform/chrome/cros_ec_sensorhub.c @@ -65,6 +65,7 @@ static int cros_ec_sensorhub_register(struct device *dev, return sensor_num; } + sensorhub->sensor_num = sensor_num; if (sensor_num == 0) { dev_err(dev, "Zero sensors reported.\n"); return -EINVAL; @@ -172,7 +173,8 @@ static int cros_ec_sensorhub_probe(struct platform_device *pdev) * If the device has sensors but does not claim to * be a sensor hub, we are in legacy mode. */ - for (i = 0; i < 2; i++) { + data->sensor_num = 2; + for (i = 0; i < data->sensor_num; i++) { ret = cros_ec_sensorhub_allocate_sensor(dev, "cros-ec-accel-legacy", i); if (ret) diff --git a/include/linux/platform_data/cros_ec_sensorhub.h b/include/linux/platform_data/cros_ec_sensorhub.h index bef7ffc7fce1..7e46a47fd642 100644 --- a/include/linux/platform_data/cros_ec_sensorhub.h +++ b/include/linux/platform_data/cros_ec_sensorhub.h @@ -22,9 +22,11 @@ struct cros_ec_sensor_platform { * struct cros_ec_sensorhub - Sensor Hub device data. * * @ec: Embedded Controller where the hub is located. + * @sensor_num: Number of MEMS sensors present in the EC. */ struct cros_ec_sensorhub { struct cros_ec_dev *ec; + int sensor_num; }; #endif /* __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H */ -- cgit From 145d59baff5944b71551ac518d7fd7d377a9c820 Mon Sep 17 00:00:00 2001 From: Gwendal Grignou Date: Fri, 27 Mar 2020 15:34:33 -0700 Subject: platform/chrome: cros_ec_sensorhub: Add FIFO support cros_ec_sensorhub registers a listener and query motion sense FIFO, spread to iio sensors registers. To test, we can use libiio: iiod& iio_readdev -u ip:localhost -T 10000 -s 25 -b 16 cros-ec-gyro | od -x Signed-off-by: Gwendal Grignou Reviewed-by: Jonathan Cameron Acked-by: Andy Shevchenko Signed-off-by: Enric Balletbo i Serra --- drivers/platform/chrome/Makefile | 3 +- drivers/platform/chrome/cros_ec_sensorhub.c | 107 ++++-- drivers/platform/chrome/cros_ec_sensorhub_ring.c | 439 +++++++++++++++++++++++ include/linux/platform_data/cros_ec_sensorhub.h | 76 ++++ 4 files changed, 597 insertions(+), 28 deletions(-) create mode 100644 drivers/platform/chrome/cros_ec_sensorhub_ring.c (limited to 'include/linux/platform_data') diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile index 198c155c7c4d..41baccba033f 100644 --- a/drivers/platform/chrome/Makefile +++ b/drivers/platform/chrome/Makefile @@ -20,7 +20,8 @@ obj-$(CONFIG_CROS_EC_CHARDEV) += cros_ec_chardev.o obj-$(CONFIG_CROS_EC_LIGHTBAR) += cros_ec_lightbar.o obj-$(CONFIG_CROS_EC_VBC) += cros_ec_vbc.o obj-$(CONFIG_CROS_EC_DEBUGFS) += cros_ec_debugfs.o -obj-$(CONFIG_CROS_EC_SENSORHUB) += cros_ec_sensorhub.o +cros-ec-sensorhub-objs := cros_ec_sensorhub.o cros_ec_sensorhub_ring.o +obj-$(CONFIG_CROS_EC_SENSORHUB) += cros-ec-sensorhub.o obj-$(CONFIG_CROS_EC_SYSFS) += cros_ec_sysfs.o obj-$(CONFIG_CROS_USBPD_LOGGER) += cros_usbpd_logger.o obj-$(CONFIG_CROS_USBPD_NOTIFY) += cros_usbpd_notify.o diff --git a/drivers/platform/chrome/cros_ec_sensorhub.c b/drivers/platform/chrome/cros_ec_sensorhub.c index 134ee5e46047..b7f2c00db5e1 100644 --- a/drivers/platform/chrome/cros_ec_sensorhub.c +++ b/drivers/platform/chrome/cros_ec_sensorhub.c @@ -50,10 +50,8 @@ static int cros_ec_sensorhub_register(struct device *dev, struct cros_ec_sensorhub *sensorhub) { int sensor_type[MOTIONSENSE_TYPE_MAX] = { 0 }; + struct cros_ec_command *msg = sensorhub->msg; struct cros_ec_dev *ec = sensorhub->ec; - struct ec_params_motion_sense *params; - struct ec_response_motion_sense *resp; - struct cros_ec_command *msg; int ret, i, sensor_num; char *name; @@ -71,22 +69,13 @@ static int cros_ec_sensorhub_register(struct device *dev, return -EINVAL; } - /* Prepare a message to send INFO command to each sensor. */ - msg = kzalloc(sizeof(*msg) + max(sizeof(*params), sizeof(*resp)), - GFP_KERNEL); - if (!msg) - return -ENOMEM; - msg->version = 1; - msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset; - msg->outsize = sizeof(*params); - msg->insize = sizeof(*resp); - params = (struct ec_params_motion_sense *)msg->data; - resp = (struct ec_response_motion_sense *)msg->data; + msg->insize = sizeof(struct ec_response_motion_sense); + msg->outsize = sizeof(struct ec_params_motion_sense); for (i = 0; i < sensor_num; i++) { - params->cmd = MOTIONSENSE_CMD_INFO; - params->info.sensor_num = i; + sensorhub->params->cmd = MOTIONSENSE_CMD_INFO; + sensorhub->params->info.sensor_num = i; ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg); if (ret < 0) { @@ -95,7 +84,7 @@ static int cros_ec_sensorhub_register(struct device *dev, continue; } - switch (resp->info.type) { + switch (sensorhub->resp->info.type) { case MOTIONSENSE_TYPE_ACCEL: name = "cros-ec-accel"; break; @@ -118,15 +107,16 @@ static int cros_ec_sensorhub_register(struct device *dev, name = "cros-ec-activity"; break; default: - dev_warn(dev, "unknown type %d\n", resp->info.type); + dev_warn(dev, "unknown type %d\n", + sensorhub->resp->info.type); continue; } ret = cros_ec_sensorhub_allocate_sensor(dev, name, i); if (ret) - goto error; + return ret; - sensor_type[resp->info.type]++; + sensor_type[sensorhub->resp->info.type]++; } if (sensor_type[MOTIONSENSE_TYPE_ACCEL] >= 2) @@ -138,29 +128,41 @@ static int cros_ec_sensorhub_register(struct device *dev, "cros-ec-lid-angle", 0); if (ret) - goto error; + return ret; } - kfree(msg); return 0; - -error: - kfree(msg); - return ret; } static int cros_ec_sensorhub_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; + struct cros_ec_dev *ec = dev_get_drvdata(dev->parent); struct cros_ec_sensorhub *data; + struct cros_ec_command *msg; int ret; int i; + msg = devm_kzalloc(dev, sizeof(struct cros_ec_command) + + max((u16)sizeof(struct ec_params_motion_sense), + ec->ec_dev->max_response), GFP_KERNEL); + if (!msg) + return -ENOMEM; + + msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset; + data = devm_kzalloc(dev, sizeof(struct cros_ec_sensorhub), GFP_KERNEL); if (!data) return -ENOMEM; - data->ec = dev_get_drvdata(dev->parent); + mutex_init(&data->cmd_lock); + + data->dev = dev; + data->ec = ec; + data->msg = msg; + data->params = (struct ec_params_motion_sense *)msg->data; + data->resp = (struct ec_response_motion_sense *)msg->data; + dev_set_drvdata(dev, data); /* Check whether this EC is a sensor hub. */ @@ -182,12 +184,63 @@ static int cros_ec_sensorhub_probe(struct platform_device *pdev) } } + /* + * If the EC does not have a FIFO, the sensors will query their data + * themselves via sysfs or a software trigger. + */ + if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) { + ret = cros_ec_sensorhub_ring_add(data); + if (ret) + return ret; + /* + * The msg and its data is not under the control of the ring + * handler. + */ + return devm_add_action_or_reset(dev, + cros_ec_sensorhub_ring_remove, + data); + } + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +/* + * When the EC is suspending, we must stop sending interrupt, + * we may use the same interrupt line for waking up the device. + * Tell the EC to stop sending non-interrupt event on the iio ring. + */ +static int cros_ec_sensorhub_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct cros_ec_sensorhub *sensorhub = platform_get_drvdata(pdev); + struct cros_ec_dev *ec = sensorhub->ec; + + if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) + return cros_ec_sensorhub_ring_fifo_enable(sensorhub, false); return 0; } +static int cros_ec_sensorhub_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct cros_ec_sensorhub *sensorhub = platform_get_drvdata(pdev); + struct cros_ec_dev *ec = sensorhub->ec; + + if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) + return cros_ec_sensorhub_ring_fifo_enable(sensorhub, true); + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(cros_ec_sensorhub_pm_ops, + cros_ec_sensorhub_suspend, + cros_ec_sensorhub_resume); + static struct platform_driver cros_ec_sensorhub_driver = { .driver = { .name = DRV_NAME, + .pm = &cros_ec_sensorhub_pm_ops, }, .probe = cros_ec_sensorhub_probe, }; diff --git a/drivers/platform/chrome/cros_ec_sensorhub_ring.c b/drivers/platform/chrome/cros_ec_sensorhub_ring.c new file mode 100644 index 000000000000..da73757529ca --- /dev/null +++ b/drivers/platform/chrome/cros_ec_sensorhub_ring.c @@ -0,0 +1,439 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for Chrome OS EC Sensor hub FIFO. + * + * Copyright 2020 Google LLC + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static inline int +cros_sensorhub_send_sample(struct cros_ec_sensorhub *sensorhub, + struct cros_ec_sensors_ring_sample *sample) +{ + cros_ec_sensorhub_push_data_cb_t cb; + int id = sample->sensor_id; + struct iio_dev *indio_dev; + + if (id > sensorhub->sensor_num) + return -EINVAL; + + cb = sensorhub->push_data[id].push_data_cb; + if (!cb) + return 0; + + indio_dev = sensorhub->push_data[id].indio_dev; + + if (sample->flag & MOTIONSENSE_SENSOR_FLAG_FLUSH) + return 0; + + return cb(indio_dev, sample->vector, sample->timestamp); +} + +/** + * cros_ec_sensorhub_register_push_data() - register the callback to the hub. + * + * @sensorhub : Sensor Hub object + * @sensor_num : The sensor the caller is interested in. + * @indio_dev : The iio device to use when a sample arrives. + * @cb : The callback to call when a sample arrives. + * + * The callback cb will be used by cros_ec_sensorhub_ring to distribute events + * from the EC. + * + * Return: 0 when callback is registered. + * EINVAL is the sensor number is invalid or the slot already used. + */ +int cros_ec_sensorhub_register_push_data(struct cros_ec_sensorhub *sensorhub, + u8 sensor_num, + struct iio_dev *indio_dev, + cros_ec_sensorhub_push_data_cb_t cb) +{ + if (sensor_num >= sensorhub->sensor_num) + return -EINVAL; + if (sensorhub->push_data[sensor_num].indio_dev) + return -EINVAL; + + sensorhub->push_data[sensor_num].indio_dev = indio_dev; + sensorhub->push_data[sensor_num].push_data_cb = cb; + + return 0; +} +EXPORT_SYMBOL_GPL(cros_ec_sensorhub_register_push_data); + +void cros_ec_sensorhub_unregister_push_data(struct cros_ec_sensorhub *sensorhub, + u8 sensor_num) +{ + sensorhub->push_data[sensor_num].indio_dev = NULL; + sensorhub->push_data[sensor_num].push_data_cb = NULL; +} +EXPORT_SYMBOL_GPL(cros_ec_sensorhub_unregister_push_data); + +/** + * cros_ec_sensorhub_ring_fifo_enable() - Enable or disable interrupt generation + * for FIFO events. + * @sensorhub: Sensor Hub object + * @on: true when events are requested. + * + * To be called before sleeping or when noone is listening. + * Return: 0 on success, or an error when we can not communicate with the EC. + * + */ +int cros_ec_sensorhub_ring_fifo_enable(struct cros_ec_sensorhub *sensorhub, + bool on) +{ + int ret; + + mutex_lock(&sensorhub->cmd_lock); + sensorhub->params->cmd = MOTIONSENSE_CMD_FIFO_INT_ENABLE; + sensorhub->params->fifo_int_enable.enable = on; + + sensorhub->msg->outsize = sizeof(struct ec_params_motion_sense); + sensorhub->msg->insize = sizeof(struct ec_response_motion_sense); + + ret = cros_ec_cmd_xfer_status(sensorhub->ec->ec_dev, sensorhub->msg); + mutex_unlock(&sensorhub->cmd_lock); + + /* We expect to receive a payload of 4 bytes, ignore. */ + if (ret > 0) + ret = 0; + + return ret; +} + +/** + * cros_ec_sensor_ring_process_event() - process one EC FIFO event + * + * @sensorhub: Sensor Hub object. + * @fifo_info: FIFO information from the EC (includes b point, EC timebase). + * @fifo_timestamp: EC IRQ, kernel timebase (aka c). + * @current_timestamp: calculated event timestamp, kernel timebase (aka a'). + * @in: incoming FIFO event from EC (includes a point, EC timebase). + * @out: outgoing event to user space (includes a'). + * + * Process one EC event, add it in the ring if necessary. + * + * Return: true if out event has been populated. + */ +static bool +cros_ec_sensor_ring_process_event(struct cros_ec_sensorhub *sensorhub, + const struct ec_response_motion_sense_fifo_info + *fifo_info, + const ktime_t fifo_timestamp, + ktime_t *current_timestamp, + struct ec_response_motion_sensor_data *in, + struct cros_ec_sensors_ring_sample *out) +{ + const s64 now = cros_ec_get_time_ns(); + int axis, async_flags; + + /* Do not populate the filter based on asynchronous events. */ + async_flags = in->flags & + (MOTIONSENSE_SENSOR_FLAG_ODR | MOTIONSENSE_SENSOR_FLAG_FLUSH); + + if (in->flags & MOTIONSENSE_SENSOR_FLAG_TIMESTAMP && !async_flags) { + s64 new_timestamp; + + /* + * Disable filtering since we might add more jitter + * if b is in a random point in time. + */ + new_timestamp = fifo_timestamp - + fifo_info->timestamp * 1000 + + in->timestamp * 1000; + + /* + * The timestamp can be stale if we had to use the fifo + * info timestamp. + */ + if (new_timestamp - *current_timestamp > 0) + *current_timestamp = new_timestamp; + } + + if (in->flags & MOTIONSENSE_SENSOR_FLAG_FLUSH) { + out->sensor_id = in->sensor_num; + out->timestamp = *current_timestamp; + out->flag = in->flags; + /* + * No other payload information provided with + * flush ack. + */ + return true; + } + + if (in->flags & MOTIONSENSE_SENSOR_FLAG_TIMESTAMP) + /* If we just have a timestamp, skip this entry. */ + return false; + + /* Regular sample */ + out->sensor_id = in->sensor_num; + if (*current_timestamp - now > 0) + /* If the timestamp is in the future. */ + out->timestamp = now; + else + out->timestamp = *current_timestamp; + + out->flag = in->flags; + for (axis = 0; axis < 3; axis++) + out->vector[axis] = in->data[axis]; + + return true; +} + +/** + * cros_ec_sensorhub_ring_handler() - The trigger handler function + * + * @sensorhub: Sensor Hub object. + * + * Called by the notifier, process the EC sensor FIFO queue. + */ +static void cros_ec_sensorhub_ring_handler(struct cros_ec_sensorhub *sensorhub) +{ + struct ec_response_motion_sense_fifo_info *fifo_info = + sensorhub->fifo_info; + struct cros_ec_dev *ec = sensorhub->ec; + ktime_t fifo_timestamp, current_timestamp; + int i, j, number_data, ret; + struct ec_response_motion_sensor_data *in; + struct cros_ec_sensors_ring_sample *out, *last_out; + + mutex_lock(&sensorhub->cmd_lock); + + /* Get FIFO information if there are lost vectors. */ + if (fifo_info->total_lost) { + int fifo_info_length = + sizeof(struct ec_response_motion_sense_fifo_info) + + sizeof(u16) * sensorhub->sensor_num; + + /* Need to retrieve the number of lost vectors per sensor */ + sensorhub->params->cmd = MOTIONSENSE_CMD_FIFO_INFO; + sensorhub->msg->outsize = 1; + sensorhub->msg->insize = fifo_info_length; + + if (cros_ec_cmd_xfer_status(ec->ec_dev, sensorhub->msg) < 0) + goto error; + + memcpy(fifo_info, &sensorhub->resp->fifo_info, + fifo_info_length); + + /* + * Update collection time, will not be as precise as the + * non-error case. + */ + fifo_timestamp = cros_ec_get_time_ns(); + } else { + fifo_timestamp = sensorhub->fifo_timestamp[ + CROS_EC_SENSOR_NEW_TS]; + } + + if (fifo_info->count > sensorhub->fifo_size || + fifo_info->size != sensorhub->fifo_size) { + dev_warn(sensorhub->dev, + "Mismatch EC data: count %d, size %d - expected %d", + fifo_info->count, fifo_info->size, + sensorhub->fifo_size); + goto error; + } + + /* Copy elements in the main fifo */ + current_timestamp = sensorhub->fifo_timestamp[CROS_EC_SENSOR_LAST_TS]; + out = sensorhub->ring; + for (i = 0; i < fifo_info->count; i += number_data) { + sensorhub->params->cmd = MOTIONSENSE_CMD_FIFO_READ; + sensorhub->params->fifo_read.max_data_vector = + fifo_info->count - i; + sensorhub->msg->outsize = + sizeof(struct ec_params_motion_sense); + sensorhub->msg->insize = + sizeof(sensorhub->resp->fifo_read) + + sensorhub->params->fifo_read.max_data_vector * + sizeof(struct ec_response_motion_sensor_data); + ret = cros_ec_cmd_xfer_status(ec->ec_dev, sensorhub->msg); + if (ret < 0) { + dev_warn(sensorhub->dev, "Fifo error: %d\n", ret); + break; + } + number_data = sensorhub->resp->fifo_read.number_data; + if (number_data == 0) { + dev_dbg(sensorhub->dev, "Unexpected empty FIFO\n"); + break; + } + if (number_data > fifo_info->count - i) { + dev_warn(sensorhub->dev, + "Invalid EC data: too many entry received: %d, expected %d", + number_data, fifo_info->count - i); + break; + } + if (out + number_data > + sensorhub->ring + fifo_info->count) { + dev_warn(sensorhub->dev, + "Too many samples: %d (%zd data) to %d entries for expected %d entries", + i, out - sensorhub->ring, i + number_data, + fifo_info->count); + break; + } + + for (in = sensorhub->resp->fifo_read.data, j = 0; + j < number_data; j++, in++) { + if (cros_ec_sensor_ring_process_event( + sensorhub, fifo_info, + fifo_timestamp, + ¤t_timestamp, + in, out)) + out++; + } + } + mutex_unlock(&sensorhub->cmd_lock); + last_out = out; + + if (out == sensorhub->ring) + /* Unexpected empty FIFO. */ + goto ring_handler_end; + + /* + * Check if current_timestamp is ahead of the last sample. + * Normally, the EC appends a timestamp after the last sample, but if + * the AP is slow to respond to the IRQ, the EC may have added new + * samples. Use the FIFO info timestamp as last timestamp then. + */ + if ((last_out - 1)->timestamp == current_timestamp) + current_timestamp = fifo_timestamp; + + /* Warn on lost samples. */ + if (fifo_info->total_lost) + for (i = 0; i < sensorhub->sensor_num; i++) { + if (fifo_info->lost[i]) + dev_warn_ratelimited(sensorhub->dev, + "Sensor %d: lost: %d out of %d\n", + i, fifo_info->lost[i], + fifo_info->total_lost); + } + + /* Push the event into the FIFO. */ + for (out = sensorhub->ring; out < last_out; out++) + cros_sensorhub_send_sample(sensorhub, out); + +ring_handler_end: + sensorhub->fifo_timestamp[CROS_EC_SENSOR_LAST_TS] = current_timestamp; + return; + +error: + mutex_unlock(&sensorhub->cmd_lock); +} + +static int cros_ec_sensorhub_event(struct notifier_block *nb, + unsigned long queued_during_suspend, + void *_notify) +{ + struct cros_ec_sensorhub *sensorhub; + struct cros_ec_device *ec_dev; + + sensorhub = container_of(nb, struct cros_ec_sensorhub, notifier); + ec_dev = sensorhub->ec->ec_dev; + + if (ec_dev->event_data.event_type != EC_MKBP_EVENT_SENSOR_FIFO) + return NOTIFY_DONE; + + if (ec_dev->event_size != sizeof(ec_dev->event_data.data.sensor_fifo)) { + dev_warn(ec_dev->dev, "Invalid fifo info size\n"); + return NOTIFY_DONE; + } + + if (queued_during_suspend) + return NOTIFY_OK; + + memcpy(sensorhub->fifo_info, &ec_dev->event_data.data.sensor_fifo.info, + sizeof(*sensorhub->fifo_info)); + sensorhub->fifo_timestamp[CROS_EC_SENSOR_NEW_TS] = + ec_dev->last_event_time; + cros_ec_sensorhub_ring_handler(sensorhub); + + return NOTIFY_OK; +} + +/** + * cros_ec_sensorhub_ring_add() - Add the FIFO functionality if the EC + * supports it. + * + * @sensorhub : Sensor Hub object. + * + * Return: 0 on success. + */ +int cros_ec_sensorhub_ring_add(struct cros_ec_sensorhub *sensorhub) +{ + struct cros_ec_dev *ec = sensorhub->ec; + int ret; + int fifo_info_length = + sizeof(struct ec_response_motion_sense_fifo_info) + + sizeof(u16) * sensorhub->sensor_num; + + /* Allocate the array for lost events. */ + sensorhub->fifo_info = devm_kzalloc(sensorhub->dev, fifo_info_length, + GFP_KERNEL); + if (!sensorhub->fifo_info) + return -ENOMEM; + + /* Retrieve FIFO information */ + sensorhub->msg->version = 2; + sensorhub->params->cmd = MOTIONSENSE_CMD_FIFO_INFO; + sensorhub->msg->outsize = 1; + sensorhub->msg->insize = fifo_info_length; + + ret = cros_ec_cmd_xfer_status(ec->ec_dev, sensorhub->msg); + if (ret < 0) + return ret; + + /* + * Allocate the full fifo. We need to copy the whole FIFO to set + * timestamps properly. + */ + sensorhub->fifo_size = sensorhub->resp->fifo_info.size; + sensorhub->ring = devm_kcalloc(sensorhub->dev, sensorhub->fifo_size, + sizeof(*sensorhub->ring), GFP_KERNEL); + if (!sensorhub->ring) + return -ENOMEM; + + /* + * Allocate the callback area based on the number of sensors. + */ + sensorhub->push_data = devm_kcalloc( + sensorhub->dev, sensorhub->sensor_num, + sizeof(*sensorhub->push_data), + GFP_KERNEL); + if (!sensorhub->push_data) + return -ENOMEM; + + sensorhub->fifo_timestamp[CROS_EC_SENSOR_LAST_TS] = + cros_ec_get_time_ns(); + + /* Register the notifier that will act as a top half interrupt. */ + sensorhub->notifier.notifier_call = cros_ec_sensorhub_event; + ret = blocking_notifier_chain_register(&ec->ec_dev->event_notifier, + &sensorhub->notifier); + if (ret < 0) + return ret; + + /* Start collection samples. */ + return cros_ec_sensorhub_ring_fifo_enable(sensorhub, true); +} + +void cros_ec_sensorhub_ring_remove(void *arg) +{ + struct cros_ec_sensorhub *sensorhub = arg; + struct cros_ec_device *ec_dev = sensorhub->ec->ec_dev; + + /* Disable the ring, prevent EC interrupt to the AP for nothing. */ + cros_ec_sensorhub_ring_fifo_enable(sensorhub, false); + blocking_notifier_chain_unregister(&ec_dev->event_notifier, + &sensorhub->notifier); +} diff --git a/include/linux/platform_data/cros_ec_sensorhub.h b/include/linux/platform_data/cros_ec_sensorhub.h index 7e46a47fd642..b0950814f820 100644 --- a/include/linux/platform_data/cros_ec_sensorhub.h +++ b/include/linux/platform_data/cros_ec_sensorhub.h @@ -8,8 +8,13 @@ #ifndef __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H #define __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H +#include +#include +#include #include +struct iio_dev; + /** * struct cros_ec_sensor_platform - ChromeOS EC sensor platform information. * @sensor_num: Id of the sensor, as reported by the EC. @@ -18,15 +23,86 @@ struct cros_ec_sensor_platform { u8 sensor_num; }; +/** + * typedef cros_ec_sensorhub_push_data_cb_t - Callback function to send datum + * to specific sensors. + * + * @indio_dev: The IIO device that will process the sample. + * @data: Vector array of the ring sample. + * @timestamp: Timestamp in host timespace when the sample was acquired by + * the EC. + */ +typedef int (*cros_ec_sensorhub_push_data_cb_t)(struct iio_dev *indio_dev, + s16 *data, + s64 timestamp); + +struct cros_ec_sensorhub_sensor_push_data { + struct iio_dev *indio_dev; + cros_ec_sensorhub_push_data_cb_t push_data_cb; +}; + +enum { + CROS_EC_SENSOR_LAST_TS, + CROS_EC_SENSOR_NEW_TS, + CROS_EC_SENSOR_ALL_TS +}; + +struct cros_ec_sensors_ring_sample { + u8 sensor_id; + u8 flag; + s16 vector[3]; + s64 timestamp; +} __packed; + /** * struct cros_ec_sensorhub - Sensor Hub device data. * + * @dev: Device object, mostly used for logging. * @ec: Embedded Controller where the hub is located. * @sensor_num: Number of MEMS sensors present in the EC. + * @msg: Structure to send FIFO requests. + * @params: Pointer to parameters in msg. + * @resp: Pointer to responses in msg. + * @cmd_lock : Lock for sending msg. + * @notifier: Notifier to kick the FIFO interrupt. + * @ring: Preprocessed ring to store events. + * @fifo_timestamp: array for event timestamp and spreading. + * @fifo_info: copy of FIFO information coming from the EC. + * @fifo_size: size of the ring. + * @push_data: array of callback to send datums to iio sensor object. */ struct cros_ec_sensorhub { + struct device *dev; struct cros_ec_dev *ec; int sensor_num; + + struct cros_ec_command *msg; + struct ec_params_motion_sense *params; + struct ec_response_motion_sense *resp; + struct mutex cmd_lock; /* Lock for protecting msg structure. */ + + struct notifier_block notifier; + + struct cros_ec_sensors_ring_sample *ring; + + ktime_t fifo_timestamp[CROS_EC_SENSOR_ALL_TS]; + struct ec_response_motion_sense_fifo_info *fifo_info; + int fifo_size; + + struct cros_ec_sensorhub_sensor_push_data *push_data; }; +int cros_ec_sensorhub_register_push_data(struct cros_ec_sensorhub *sensorhub, + u8 sensor_num, + struct iio_dev *indio_dev, + cros_ec_sensorhub_push_data_cb_t cb); + +void cros_ec_sensorhub_unregister_push_data(struct cros_ec_sensorhub *sensorhub, + u8 sensor_num); + +int cros_ec_sensorhub_ring_add(struct cros_ec_sensorhub *sensorhub); +void cros_ec_sensorhub_ring_remove(void *arg); +int cros_ec_sensorhub_ring_fifo_enable(struct cros_ec_sensorhub *sensorhub, + bool on); + #endif /* __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H */ -- cgit From 93fe48a585905675719835f8269258736de0948f Mon Sep 17 00:00:00 2001 From: Gwendal Grignou Date: Fri, 27 Mar 2020 15:34:35 -0700 Subject: platform/chrome: cros_ec_sensorhub: Add median filter Events are timestamped in EC time space, their timestamps need to be converted in host time space. The assumption is the time delta between when the interrupt is sent by the EC and when it is receive by the host is a [small] constant. This is not always true, even with hard-wired interrupt. To mitigate worst offenders, add a median filter to weed out bigger than expected delays. Signed-off-by: Gwendal Grignou Acked-by: Jonathan Cameron Acked-by: Lee Jones Acked-by: Andy Shevchenko Signed-off-by: Enric Balletbo i Serra --- drivers/platform/chrome/cros_ec_sensorhub_ring.c | 560 +++++++++++++++++++++-- include/linux/platform_data/cros_ec_sensorhub.h | 93 +++- 2 files changed, 622 insertions(+), 31 deletions(-) (limited to 'include/linux/platform_data') diff --git a/drivers/platform/chrome/cros_ec_sensorhub_ring.c b/drivers/platform/chrome/cros_ec_sensorhub_ring.c index 443db8277d2b..230e6cf3da2f 100644 --- a/drivers/platform/chrome/cros_ec_sensorhub_ring.c +++ b/drivers/platform/chrome/cros_ec_sensorhub_ring.c @@ -17,6 +17,21 @@ #include #include +/* Precision of fixed point for the m values from the filter */ +#define M_PRECISION BIT(23) + +/* Only activate the filter once we have at least this many elements. */ +#define TS_HISTORY_THRESHOLD 8 + +/* + * If we don't have any history entries for this long, empty the filter to + * make sure there are no big discontinuities. + */ +#define TS_HISTORY_BORED_US 500000 + +/* To measure by how much the filter is overshooting, if it happens. */ +#define FUTURE_TS_ANALYTICS_COUNT_MAX 100 + static inline int cros_sensorhub_send_sample(struct cros_ec_sensorhub *sensorhub, struct cros_ec_sensors_ring_sample *sample) @@ -92,9 +107,13 @@ EXPORT_SYMBOL_GPL(cros_ec_sensorhub_unregister_push_data); int cros_ec_sensorhub_ring_fifo_enable(struct cros_ec_sensorhub *sensorhub, bool on) { - int ret; + int ret, i; mutex_lock(&sensorhub->cmd_lock); + if (sensorhub->tight_timestamps) + for (i = 0; i < sensorhub->sensor_num; i++) + sensorhub->batch_state[i].last_len = 0; + sensorhub->params->cmd = MOTIONSENSE_CMD_FIFO_INT_ENABLE; sensorhub->params->fifo_int_enable.enable = on; @@ -111,8 +130,245 @@ int cros_ec_sensorhub_ring_fifo_enable(struct cros_ec_sensorhub *sensorhub, return ret; } +static int cros_ec_sensor_ring_median_cmp(const void *pv1, const void *pv2) +{ + s64 v1 = *(s64 *)pv1; + s64 v2 = *(s64 *)pv2; + + if (v1 > v2) + return 1; + else if (v1 < v2) + return -1; + else + return 0; +} + +/* + * cros_ec_sensor_ring_median: Gets median of an array of numbers + * + * For now it's implemented using an inefficient > O(n) sort then return + * the middle element. A more optimal method would be something like + * quickselect, but given that n = 64 we can probably live with it in the + * name of clarity. + * + * Warning: the input array gets modified (sorted)! + */ +static s64 cros_ec_sensor_ring_median(s64 *array, size_t length) +{ + sort(array, length, sizeof(s64), cros_ec_sensor_ring_median_cmp, NULL); + return array[length / 2]; +} + +/* + * IRQ Timestamp Filtering + * + * Lower down in cros_ec_sensor_ring_process_event(), for each sensor event + * we have to calculate it's timestamp in the AP timebase. There are 3 time + * points: + * a - EC timebase, sensor event + * b - EC timebase, IRQ + * c - AP timebase, IRQ + * a' - what we want: sensor even in AP timebase + * + * While a and b are recorded at accurate times (due to the EC real time + * nature); c is pretty untrustworthy, even though it's recorded the + * first thing in ec_irq_handler(). There is a very good change we'll get + * added lantency due to: + * other irqs + * ddrfreq + * cpuidle + * + * Normally a' = c - b + a, but if we do that naive math any jitter in c + * will get coupled in a', which we don't want. We want a function + * a' = cros_ec_sensor_ring_ts_filter(a) which will filter out outliers in c. + * + * Think of a graph of AP time(b) on the y axis vs EC time(c) on the x axis. + * The slope of the line won't be exactly 1, there will be some clock drift + * between the 2 chips for various reasons (mechanical stress, temperature, + * voltage). We need to extrapolate values for a future x, without trusting + * recent y values too much. + * + * We use a median filter for the slope, then another median filter for the + * y-intercept to calculate this function: + * dx[n] = x[n-1] - x[n] + * dy[n] = x[n-1] - x[n] + * m[n] = dy[n] / dx[n] + * median_m = median(m[n-k:n]) + * error[i] = y[n-i] - median_m * x[n-i] + * median_error = median(error[:k]) + * predicted_y = median_m * x + median_error + * + * Implementation differences from above: + * - Redefined y to be actually c - b, this gives us a lot more precision + * to do the math. (c-b)/b variations are more obvious than c/b variations. + * - Since we don't have floating point, any operations involving slope are + * done using fixed point math (*M_PRECISION) + * - Since x and y grow with time, we keep zeroing the graph (relative to + * the last sample), this way math involving *x[n-i] will not overflow + * - EC timestamps are kept in us, it improves the slope calculation precision + */ + +/** + * cros_ec_sensor_ring_ts_filter_update() - Update filter history. + * + * @state: Filter information. + * @b: IRQ timestamp, EC timebase (us) + * @c: IRQ timestamp, AP timebase (ns) + * + * Given a new IRQ timestamp pair (EC and AP timebases), add it to the filter + * history. + */ +static void +cros_ec_sensor_ring_ts_filter_update(struct cros_ec_sensors_ts_filter_state + *state, + s64 b, s64 c) +{ + s64 x, y; + s64 dx, dy; + s64 m; /* stored as *M_PRECISION */ + s64 *m_history_copy = state->temp_buf; + s64 *error = state->temp_buf; + int i; + + /* we trust b the most, that'll be our independent variable */ + x = b; + /* y is the offset between AP and EC times, in ns */ + y = c - b * 1000; + + dx = (state->x_history[0] + state->x_offset) - x; + if (dx == 0) + return; /* we already have this irq in the history */ + dy = (state->y_history[0] + state->y_offset) - y; + m = div64_s64(dy * M_PRECISION, dx); + + /* Empty filter if we haven't seen any action in a while. */ + if (-dx > TS_HISTORY_BORED_US) + state->history_len = 0; + + /* Move everything over, also update offset to all absolute coords .*/ + for (i = state->history_len - 1; i >= 1; i--) { + state->x_history[i] = state->x_history[i - 1] + dx; + state->y_history[i] = state->y_history[i - 1] + dy; + + state->m_history[i] = state->m_history[i - 1]; + /* + * Also use the same loop to copy m_history for future + * median extraction. + */ + m_history_copy[i] = state->m_history[i - 1]; + } + + /* Store the x and y, but remember offset is actually last sample. */ + state->x_offset = x; + state->y_offset = y; + state->x_history[0] = 0; + state->y_history[0] = 0; + + state->m_history[0] = m; + m_history_copy[0] = m; + + if (state->history_len < CROS_EC_SENSORHUB_TS_HISTORY_SIZE) + state->history_len++; + + /* Precalculate things for the filter. */ + if (state->history_len > TS_HISTORY_THRESHOLD) { + state->median_m = + cros_ec_sensor_ring_median(m_history_copy, + state->history_len - 1); + + /* + * Calculate y-intercepts as if m_median is the slope and + * points in the history are on the line. median_error will + * still be in the offset coordinate system. + */ + for (i = 0; i < state->history_len; i++) + error[i] = state->y_history[i] - + div_s64(state->median_m * state->x_history[i], + M_PRECISION); + state->median_error = + cros_ec_sensor_ring_median(error, state->history_len); + } else { + state->median_m = 0; + state->median_error = 0; + } +} + +/** + * cros_ec_sensor_ring_ts_filter() - Translate EC timebase timestamp to AP + * timebase + * + * @state: filter information. + * @x: any ec timestamp (us): + * + * cros_ec_sensor_ring_ts_filter(a) => a' event timestamp, AP timebase + * cros_ec_sensor_ring_ts_filter(b) => calculated timestamp when the EC IRQ + * should have happened on the AP, with low jitter + * + * Note: The filter will only activate once state->history_len goes + * over TS_HISTORY_THRESHOLD. Otherwise it'll just do the naive c - b + a + * transform. + * + * How to derive the formula, starting from: + * f(x) = median_m * x + median_error + * That's the calculated AP - EC offset (at the x point in time) + * Undo the coordinate system transform: + * f(x) = median_m * (x - x_offset) + median_error + y_offset + * Remember to undo the "y = c - b * 1000" modification: + * f(x) = median_m * (x - x_offset) + median_error + y_offset + x * 1000 + * + * Return: timestamp in AP timebase (ns) + */ +static s64 +cros_ec_sensor_ring_ts_filter(struct cros_ec_sensors_ts_filter_state *state, + s64 x) +{ + return div_s64(state->median_m * (x - state->x_offset), M_PRECISION) + + state->median_error + state->y_offset + x * 1000; +} + +/* + * Since a and b were originally 32 bit values from the EC, + * they overflow relatively often, casting is not enough, so we need to + * add an offset. + */ +static void +cros_ec_sensor_ring_fix_overflow(s64 *ts, + const s64 overflow_period, + struct cros_ec_sensors_ec_overflow_state + *state) +{ + s64 adjust; + + *ts += state->offset; + if (abs(state->last - *ts) > (overflow_period / 2)) { + adjust = state->last > *ts ? overflow_period : -overflow_period; + state->offset += adjust; + *ts += adjust; + } + state->last = *ts; +} + +static void +cros_ec_sensor_ring_check_for_past_timestamp(struct cros_ec_sensorhub + *sensorhub, + struct cros_ec_sensors_ring_sample + *sample) +{ + const u8 sensor_id = sample->sensor_id; + + /* If this event is earlier than one we saw before... */ + if (sensorhub->batch_state[sensor_id].newest_sensor_event > + sample->timestamp) + /* mark it for spreading. */ + sample->timestamp = + sensorhub->batch_state[sensor_id].last_ts; + else + sensorhub->batch_state[sensor_id].newest_sensor_event = + sample->timestamp; +} + /** - * cros_ec_sensor_ring_process_event() - process one EC FIFO event + * cros_ec_sensor_ring_process_event() - Process one EC FIFO event * * @sensorhub: Sensor Hub object. * @fifo_info: FIFO information from the EC (includes b point, EC timebase). @@ -142,28 +398,57 @@ cros_ec_sensor_ring_process_event(struct cros_ec_sensorhub *sensorhub, (MOTIONSENSE_SENSOR_FLAG_ODR | MOTIONSENSE_SENSOR_FLAG_FLUSH); if (in->flags & MOTIONSENSE_SENSOR_FLAG_TIMESTAMP && !async_flags) { - s64 new_timestamp; + s64 a = in->timestamp; + s64 b = fifo_info->timestamp; + s64 c = fifo_timestamp; + + cros_ec_sensor_ring_fix_overflow(&a, 1LL << 32, + &sensorhub->overflow_a); + cros_ec_sensor_ring_fix_overflow(&b, 1LL << 32, + &sensorhub->overflow_b); + + if (sensorhub->tight_timestamps) { + cros_ec_sensor_ring_ts_filter_update( + &sensorhub->filter, b, c); + *current_timestamp = cros_ec_sensor_ring_ts_filter( + &sensorhub->filter, a); + } else { + s64 new_timestamp; - /* - * Disable filtering since we might add more jitter - * if b is in a random point in time. - */ - new_timestamp = fifo_timestamp - - fifo_info->timestamp * 1000 + - in->timestamp * 1000; + /* + * Disable filtering since we might add more jitter + * if b is in a random point in time. + */ + new_timestamp = fifo_timestamp - + fifo_info->timestamp * 1000 + + in->timestamp * 1000; + /* + * The timestamp can be stale if we had to use the fifo + * info timestamp. + */ + if (new_timestamp - *current_timestamp > 0) + *current_timestamp = new_timestamp; + } + } + if (in->flags & MOTIONSENSE_SENSOR_FLAG_ODR) { + if (sensorhub->tight_timestamps) { + sensorhub->batch_state[in->sensor_num].last_len = 0; + sensorhub->batch_state[in->sensor_num].penul_len = 0; + } /* - * The timestamp can be stale if we had to use the fifo - * info timestamp. + * ODR change is only useful for the sensor_ring, it does not + * convey information to clients. */ - if (new_timestamp - *current_timestamp > 0) - *current_timestamp = new_timestamp; + return false; } if (in->flags & MOTIONSENSE_SENSOR_FLAG_FLUSH) { out->sensor_id = in->sensor_num; out->timestamp = *current_timestamp; out->flag = in->flags; + if (sensorhub->tight_timestamps) + sensorhub->batch_state[out->sensor_id].last_len = 0; /* * No other payload information provided with * flush ack. @@ -177,22 +462,221 @@ cros_ec_sensor_ring_process_event(struct cros_ec_sensorhub *sensorhub, /* Regular sample */ out->sensor_id = in->sensor_num; - if (*current_timestamp - now > 0) - /* If the timestamp is in the future. */ + if (*current_timestamp - now > 0) { + /* + * This fix is needed to overcome the timestamp filter putting + * events in the future. + */ + sensorhub->future_timestamp_total_ns += + *current_timestamp - now; + if (++sensorhub->future_timestamp_count == + FUTURE_TS_ANALYTICS_COUNT_MAX) { + s64 avg = div_s64(sensorhub->future_timestamp_total_ns, + sensorhub->future_timestamp_count); + dev_warn_ratelimited(sensorhub->dev, + "100 timestamps in the future, %lldns shaved on average\n", + avg); + sensorhub->future_timestamp_count = 0; + sensorhub->future_timestamp_total_ns = 0; + } out->timestamp = now; - else + } else { out->timestamp = *current_timestamp; + } out->flag = in->flags; for (axis = 0; axis < 3; axis++) out->vector[axis] = in->data[axis]; + if (sensorhub->tight_timestamps) + cros_ec_sensor_ring_check_for_past_timestamp(sensorhub, out); return true; } /* * cros_ec_sensor_ring_spread_add: Calculate proper timestamps then add to - * ringbuffer. + * ringbuffer. + * + * This is the new spreading code, assumes every sample's timestamp + * preceeds the sample. Run if tight_timestamps == true. + * + * Sometimes the EC receives only one interrupt (hence timestamp) for + * a batch of samples. Only the first sample will have the correct + * timestamp. So we must interpolate the other samples. + * We use the previous batch timestamp and our current batch timestamp + * as a way to calculate period, then spread the samples evenly. + * + * s0 int, 0ms + * s1 int, 10ms + * s2 int, 20ms + * 30ms point goes by, no interrupt, previous one is still asserted + * downloading s2 and s3 + * s3 sample, 20ms (incorrect timestamp) + * s4 int, 40ms + * + * The batches are [(s0), (s1), (s2, s3), (s4)]. Since the 3rd batch + * has 2 samples in them, we adjust the timestamp of s3. + * s2 - s1 = 10ms, so s3 must be s2 + 10ms => 20ms. If s1 would have + * been part of a bigger batch things would have gotten a little + * more complicated. + * + * Note: we also assume another sensor sample doesn't break up a batch + * in 2 or more partitions. Example, there can't ever be a sync sensor + * in between S2 and S3. This simplifies the following code. + */ +static void +cros_ec_sensor_ring_spread_add(struct cros_ec_sensorhub *sensorhub, + unsigned long sensor_mask, + struct cros_ec_sensors_ring_sample *last_out) +{ + struct cros_ec_sensors_ring_sample *batch_start, *next_batch_start; + int id; + + for_each_set_bit(id, &sensor_mask, sensorhub->sensor_num) { + for (batch_start = sensorhub->ring; batch_start < last_out; + batch_start = next_batch_start) { + /* + * For each batch (where all samples have the same + * timestamp). + */ + int batch_len, sample_idx; + struct cros_ec_sensors_ring_sample *batch_end = + batch_start; + struct cros_ec_sensors_ring_sample *s; + s64 batch_timestamp = batch_start->timestamp; + s64 sample_period; + + /* + * Skip over batches that start with the sensor types + * we're not looking at right now. + */ + if (batch_start->sensor_id != id) { + next_batch_start = batch_start + 1; + continue; + } + + /* + * Do not start a batch + * from a flush, as it happens asynchronously to the + * regular flow of events. + */ + if (batch_start->flag & MOTIONSENSE_SENSOR_FLAG_FLUSH) { + cros_sensorhub_send_sample(sensorhub, + batch_start); + next_batch_start = batch_start + 1; + continue; + } + + if (batch_start->timestamp <= + sensorhub->batch_state[id].last_ts) { + batch_timestamp = + sensorhub->batch_state[id].last_ts; + batch_len = sensorhub->batch_state[id].last_len; + + sample_idx = batch_len; + + sensorhub->batch_state[id].last_ts = + sensorhub->batch_state[id].penul_ts; + sensorhub->batch_state[id].last_len = + sensorhub->batch_state[id].penul_len; + } else { + /* + * Push first sample in the batch to the, + * kifo, it's guaranteed to be correct, the + * rest will follow later on. + */ + sample_idx = 1; + batch_len = 1; + cros_sensorhub_send_sample(sensorhub, + batch_start); + batch_start++; + } + + /* Find all samples have the same timestamp. */ + for (s = batch_start; s < last_out; s++) { + if (s->sensor_id != id) + /* + * Skip over other sensor types that + * are interleaved, don't count them. + */ + continue; + if (s->timestamp != batch_timestamp) + /* we discovered the next batch */ + break; + if (s->flag & MOTIONSENSE_SENSOR_FLAG_FLUSH) + /* break on flush packets */ + break; + batch_end = s; + batch_len++; + } + + if (batch_len == 1) + goto done_with_this_batch; + + /* Can we calculate period? */ + if (sensorhub->batch_state[id].last_len == 0) { + dev_warn(sensorhub->dev, "Sensor %d: lost %d samples when spreading\n", + id, batch_len - 1); + goto done_with_this_batch; + /* + * Note: we're dropping the rest of the samples + * in this batch since we have no idea where + * they're supposed to go without a period + * calculation. + */ + } + + sample_period = div_s64(batch_timestamp - + sensorhub->batch_state[id].last_ts, + sensorhub->batch_state[id].last_len); + dev_dbg(sensorhub->dev, + "Adjusting %d samples, sensor %d last_batch @%lld (%d samples) batch_timestamp=%lld => period=%lld\n", + batch_len, id, + sensorhub->batch_state[id].last_ts, + sensorhub->batch_state[id].last_len, + batch_timestamp, + sample_period); + + /* + * Adjust timestamps of the samples then push them to + * kfifo. + */ + for (s = batch_start; s <= batch_end; s++) { + if (s->sensor_id != id) + /* + * Skip over other sensor types that + * are interleaved, don't change them. + */ + continue; + + s->timestamp = batch_timestamp + + sample_period * sample_idx; + sample_idx++; + + cros_sensorhub_send_sample(sensorhub, s); + } + +done_with_this_batch: + sensorhub->batch_state[id].penul_ts = + sensorhub->batch_state[id].last_ts; + sensorhub->batch_state[id].penul_len = + sensorhub->batch_state[id].last_len; + + sensorhub->batch_state[id].last_ts = + batch_timestamp; + sensorhub->batch_state[id].last_len = batch_len; + + next_batch_start = batch_end + 1; + } + } +} + +/* + * cros_ec_sensor_ring_spread_add_legacy: Calculate proper timestamps then + * add to ringbuffer (legacy). + * + * Note: This assumes we're running old firmware, where every sample's timestamp + * is after the sample. Run if tight_timestamps == false. * * If there is a sample with a proper timestamp * @@ -215,11 +699,12 @@ cros_ec_sensor_ring_process_event(struct cros_ec_sensorhub *sensorhub, * * We know have [TS1+1/3, TS1+2/3, current timestamp] */ -static void cros_ec_sensor_ring_spread_add(struct cros_ec_sensorhub *sensorhub, - unsigned long sensor_mask, - s64 current_timestamp, - struct cros_ec_sensors_ring_sample - *last_out) +static void +cros_ec_sensor_ring_spread_add_legacy(struct cros_ec_sensorhub *sensorhub, + unsigned long sensor_mask, + s64 current_timestamp, + struct cros_ec_sensors_ring_sample + *last_out) { struct cros_ec_sensors_ring_sample *out; int i; @@ -404,25 +889,34 @@ static void cros_ec_sensorhub_ring_handler(struct cros_ec_sensorhub *sensorhub) * is slow to respond to the IRQ, the EC may have added new samples. * Use the FIFO info timestamp as last timestamp then. */ - if ((last_out - 1)->timestamp == current_timestamp) + if (!sensorhub->tight_timestamps && + (last_out - 1)->timestamp == current_timestamp) current_timestamp = fifo_timestamp; /* Warn on lost samples. */ if (fifo_info->total_lost) for (i = 0; i < sensorhub->sensor_num; i++) { - if (fifo_info->lost[i]) + if (fifo_info->lost[i]) { dev_warn_ratelimited(sensorhub->dev, "Sensor %d: lost: %d out of %d\n", i, fifo_info->lost[i], fifo_info->total_lost); + if (sensorhub->tight_timestamps) + sensorhub->batch_state[i].last_len = 0; + } } /* * Spread samples in case of batching, then add them to the * ringbuffer. */ - cros_ec_sensor_ring_spread_add(sensorhub, sensor_mask, - current_timestamp, last_out); + if (sensorhub->tight_timestamps) + cros_ec_sensor_ring_spread_add(sensorhub, sensor_mask, + last_out); + else + cros_ec_sensor_ring_spread_add_legacy(sensorhub, sensor_mask, + current_timestamp, + last_out); ring_handler_end: sensorhub->fifo_timestamp[CROS_EC_SENSOR_LAST_TS] = current_timestamp; @@ -517,6 +1011,18 @@ int cros_ec_sensorhub_ring_add(struct cros_ec_sensorhub *sensorhub) sensorhub->fifo_timestamp[CROS_EC_SENSOR_LAST_TS] = cros_ec_get_time_ns(); + sensorhub->tight_timestamps = cros_ec_check_features( + ec, EC_FEATURE_MOTION_SENSE_TIGHT_TIMESTAMPS); + + if (sensorhub->tight_timestamps) { + sensorhub->batch_state = devm_kcalloc(sensorhub->dev, + sensorhub->sensor_num, + sizeof(*sensorhub->batch_state), + GFP_KERNEL); + if (!sensorhub->batch_state) + return -ENOMEM; + } + /* Register the notifier that will act as a top half interrupt. */ sensorhub->notifier.notifier_call = cros_ec_sensorhub_event; ret = blocking_notifier_chain_register(&ec->ec_dev->event_notifier, diff --git a/include/linux/platform_data/cros_ec_sensorhub.h b/include/linux/platform_data/cros_ec_sensorhub.h index b0950814f820..c588be843f61 100644 --- a/include/linux/platform_data/cros_ec_sensorhub.h +++ b/include/linux/platform_data/cros_ec_sensorhub.h @@ -54,7 +54,64 @@ struct cros_ec_sensors_ring_sample { s64 timestamp; } __packed; +/* State used for cros_ec_ring_fix_overflow */ +struct cros_ec_sensors_ec_overflow_state { + s64 offset; + s64 last; +}; + +/* Length of the filter, how long to remember entries for */ +#define CROS_EC_SENSORHUB_TS_HISTORY_SIZE 64 + /** + * struct cros_ec_sensors_ts_filter_state - Timestamp filetr state. + * + * @x_offset: x is EC interrupt time. x_offset its last value. + * @y_offset: y is the difference between AP and EC time, y_offset its last + * value. + * @x_history: The past history of x, relative to x_offset. + * @y_history: The past history of y, relative to y_offset. + * @m_history: rate between y and x. + * @history_len: Amount of valid historic data in the arrays. + * @temp_buf: Temporary buffer used when updating the filter. + * @median_m: median value of m_history + * @median_error: final error to apply to AP interrupt timestamp to get the + * "true timestamp" the event occurred. + */ +struct cros_ec_sensors_ts_filter_state { + s64 x_offset, y_offset; + s64 x_history[CROS_EC_SENSORHUB_TS_HISTORY_SIZE]; + s64 y_history[CROS_EC_SENSORHUB_TS_HISTORY_SIZE]; + s64 m_history[CROS_EC_SENSORHUB_TS_HISTORY_SIZE]; + int history_len; + + s64 temp_buf[CROS_EC_SENSORHUB_TS_HISTORY_SIZE]; + + s64 median_m; + s64 median_error; +}; + +/* struct cros_ec_sensors_ts_batch_state - State of batch of a single sensor. + * + * Use to store information to batch data using median fileter information. + * + * @penul_ts: last but one batch timestamp (penultimate timestamp). + * Used for timestamp spreading calculations + * when a batch shows up. + * @penul_len: last but one batch length. + * @last_ts: Last batch timestam. + * @last_len: Last batch length. + * @newest_sensor_event: Last sensor timestamp. + */ +struct cros_ec_sensors_ts_batch_state { + s64 penul_ts; + int penul_len; + s64 last_ts; + int last_len; + s64 newest_sensor_event; +}; + +/* * struct cros_ec_sensorhub - Sensor Hub device data. * * @dev: Device object, mostly used for logging. @@ -66,10 +123,26 @@ struct cros_ec_sensors_ring_sample { * @cmd_lock : Lock for sending msg. * @notifier: Notifier to kick the FIFO interrupt. * @ring: Preprocessed ring to store events. - * @fifo_timestamp: array for event timestamp and spreading. - * @fifo_info: copy of FIFO information coming from the EC. - * @fifo_size: size of the ring. - * @push_data: array of callback to send datums to iio sensor object. + * @fifo_timestamp: Array for event timestamp and spreading. + * @fifo_info: Copy of FIFO information coming from the EC. + * @fifo_size: Size of the ring. + * @batch_state: Per sensor information of the last batches received. + * @overflow_a: For handling timestamp overflow for a time (sensor events) + * @overflow_b: For handling timestamp overflow for b time (ec interrupts) + * @filter: Medium fileter structure. + * @tight_timestamps: Set to truen when EC support tight timestamping: + * The timestamps reported from the EC have low jitter. + * Timestamps also come before every sample. Set either + * by feature bits coming from the EC or userspace. + * @future_timestamp_count: Statistics used to compute shaved time. + * This occurs when timestamp interpolation from EC + * time to AP time accidentally puts timestamps in + * the future. These timestamps are clamped to + * `now` and these count/total_ns maintain the + * statistics for how much time was removed in a + * given period. + * @future_timestamp_total_ns: Total amount of time shaved. + * @push_data: Array of callback to send datums to iio sensor object. */ struct cros_ec_sensorhub { struct device *dev; @@ -89,6 +162,18 @@ struct cros_ec_sensorhub { struct ec_response_motion_sense_fifo_info *fifo_info; int fifo_size; + struct cros_ec_sensors_ts_batch_state *batch_state; + + struct cros_ec_sensors_ec_overflow_state overflow_a; + struct cros_ec_sensors_ec_overflow_state overflow_b; + + struct cros_ec_sensors_ts_filter_state filter; + + int tight_timestamps; + + s32 future_timestamp_count; + s64 future_timestamp_total_ns; + struct cros_ec_sensorhub_sensor_push_data *push_data; }; -- cgit