/* SPDX-License-Identifier: GPL-2.0 */ /* * Chrome OS EC MEMS Sensor Hub driver. * * Copyright 2019 Google LLC */ #ifndef __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H #define __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H #include <linux/ktime.h> #include <linux/mutex.h> #include <linux/notifier.h> #include <linux/platform_data/cros_ec_commands.h> struct iio_dev; /** * struct cros_ec_sensor_platform - ChromeOS EC sensor platform information. * @sensor_num: Id of the sensor, as reported by the EC. */ 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; /* 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. * @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. * @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; 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_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; }; 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_allocate(struct cros_ec_sensorhub *sensorhub); 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 */
