/* Copyright 2021 The Chromium OS Authors. All rights reserved. * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ /** * @file * * @brief Backend API for BMI emulator */ #ifndef __EMUL_BMI_H #define __EMUL_BMI_H #include #include #include /** * @brief BMI emulator backend API * @defgroup bmi_emul BMI emulator * @{ * * BMI emulator supports responses to all write and read I2C messages. * Accelerometer and gyroscope registers are obtained from internal emulator * state, range register and offset. FIFO is fully simulated. Emulator can be * extended to support more models of BMI. * Application may alter emulator state: * * - define a Device Tree overlay file to set which inadvisable driver behaviour * should be treated as errors and which model is emulated * - call @ref bmi_emul_set_reg and @ref bmi_emul_get_reg to set and get value * of BMI registers * - call @ref bmi_emul_set_off and @ref bmi_emul_get_off to set and get * internal offset value * - call @ref bmi_emul_set_value and @ref bmi_emul_get_value to set and get * accelerometer or gyroscope value * - call bmi_emul_set_err_* to change emulator behaviour on inadvisable driver * behaviour * - call @ref bmi_emul_simulate_cmd_exec_time to enable or disable simulation * of command execution time * - call @ref bmi_emul_append_frame to add frame to FIFO * - call @reg bmi_emul_set_skipped_frames to generate skip frame on next access * to FIFO * - call functions from emul_common_i2c.h to setup custom handlers for I2C * messages */ /** * Axis argument used in @ref bmi_emul_set_value @ref bmi_emul_get_value * @ref bmi_emul_set_off and @ref bmi_emul_get_off */ enum bmi_emul_axis { BMI_EMUL_ACC_X, BMI_EMUL_ACC_Y, BMI_EMUL_ACC_Z, BMI_EMUL_GYR_X, BMI_EMUL_GYR_Y, BMI_EMUL_GYR_Z, }; /** BMI emulator models */ #define BMI_EMUL_160 1 #define BMI_EMUL_260 2 /** Last register supported by emulator */ #define BMI_EMUL_MAX_REG 0x80 /** Maximum number of registers that can be backed in NVM */ #define BMI_EMUL_MAX_NVM_REGS 10 /** Headers used in FIFO frames */ #define BMI_EMUL_FIFO_HEAD_SKIP 0x40 #define BMI_EMUL_FIFO_HEAD_TIME 0x44 #define BMI_EMUL_FIFO_HEAD_CONFIG 0x48 #define BMI_EMUL_FIFO_HEAD_EMPTY 0x80 #define BMI_EMUL_FIFO_HEAD_DATA 0x80 #define BMI_EMUL_FIFO_HEAD_DATA_MAG BIT(4) #define BMI_EMUL_FIFO_HEAD_DATA_GYR BIT(3) #define BMI_EMUL_FIFO_HEAD_DATA_ACC BIT(2) #define BMI_EMUL_FIFO_HEAD_DATA_TAG_MASK 0x03 /** * Acceleration 1g in internal emulator units. It is helpful for using * functions @ref bmi_emul_set_value @ref bmi_emul_get_value * @ref bmi_emul_set_off and @ref bmi_emul_get_off */ #define BMI_EMUL_1G BIT(14) /** * Gyroscope 125°/s in internal emulator units. It is helpful for using * functions @ref bmi_emul_set_value @ref bmi_emul_get_value * @ref bmi_emul_set_off and @ref bmi_emul_get_off */ #define BMI_EMUL_125_DEG_S BIT(15) /** Type of frames that can be added to the emulator frames list */ #define BMI_EMUL_FRAME_CONFIG BIT(0) #define BMI_EMUL_FRAME_ACC BIT(1) #define BMI_EMUL_FRAME_MAG BIT(2) #define BMI_EMUL_FRAME_GYR BIT(3) /** * Code returned by model specific handle_read and handle_write functions, when * RO register is accessed on write or WO register is accessed on read */ #define BMI_EMUL_ACCESS_E 1 /** Structure used to describe single FIFO frame */ struct bmi_emul_frame { /** Type of frame */ uint8_t type; /** Tag added to data frame */ uint8_t tag; /** Value used in config frame */ uint8_t config; /** Accelerometer sensor values in internal emulator units */ int32_t acc_x; int32_t acc_y; int32_t acc_z; /** Gyroscope sensor values in internal emulator units */ int32_t gyr_x; int32_t gyr_y; int32_t gyr_z; /** Magnetometer/other sensor values in internal emulator units */ int32_t mag_x; int32_t mag_y; int32_t mag_z; int32_t rhall; /** Pointer to next frame or NULL */ struct bmi_emul_frame *next; }; /** Structure describing specific BMI model */ struct bmi_emul_type_data { /** Indicate if time frame should follow config frame */ bool sensortime_follow_config_frame; /** * @brief Compute register address that acctually will be accessed, when * selected register is @p reg and there was @p byte handled in * the current I2C message * * @param emul Pointer to BMI emulator * @param reg Selected register * @param byte Number of handled bytes in the current I2C message * @param read If current I2C message is read * * @return Register address that will be accessed */ int (*access_reg)(struct i2c_emul *emul, int reg, int byte, bool read); /** * @brief Model specific write function. It should modify state of * emulator if required. * * @param regs Pointer to array of emulator's registers * @param emul Pointer to BMI emulator * @param reg Selected register * @param byte Number of handled bytes in this write command * @param val Value that is being written * * @return 0 on success * @return BMI_EMUL_ACCESS_E on RO register access * @return other on error */ int (*handle_write)(uint8_t *regs, struct i2c_emul *emul, int reg, int byte, uint8_t val); /** * @brief Model specific read function. It should modify state of * emulator if required. @p buf should be set to response value. * * @param regs Pointer to array of emulator's registers * @param emul Pointer to BMI emulator * @param reg Selected register * @param byte Byte which is accessed during block read * @param buf Pointer where read byte should be stored * * @return 0 on success * @return BMI_EMUL_ACCESS_E on WO register access * @return other on error */ int (*handle_read)(uint8_t *regs, struct i2c_emul *emul, int reg, int byte, char *buf); /** * @brief Model specific reset function. It should modify state of * emulator to imitate after reset conditions. * * @param regs Pointer to array of emulator's registers * @param emul Pointer to BMI emulator */ void (*reset)(uint8_t *regs, struct i2c_emul *emul); /** Array of reserved bits mask for each register */ const uint8_t *rsvd_mask; /** Array of registers that are backed in NVM */ const int *nvm_reg; /** Number of registers backed in NVM */ int nvm_len; /** Gyroscope X axis register */ int gyr_off_reg; /** Accelerometer X axis register */ int acc_off_reg; /** Gyroscope 9 and 8 bits register */ int gyr98_off_reg; }; /** * @brief Get BMI160 model specific structure. * * @return Pointer to BMI160 specific structure */ const struct bmi_emul_type_data *get_bmi160_emul_type_data(void); /** * @brief Get BMI260 model specific structure. * * @return Pointer to BMI260 specific structure */ const struct bmi_emul_type_data *get_bmi260_emul_type_data(void); /** * @brief Get pointer to BMI emulator using device tree order number. * * @param ord Device tree order number obtained from DT_DEP_ORD macro * * @return Pointer to BMI emulator */ struct i2c_emul *bmi_emul_get(int ord); /** * @brief Set value of given register of BMI * * @param emul Pointer to BMI emulator * @param reg Register address which value will be changed * @param val New value of the register */ void bmi_emul_set_reg(struct i2c_emul *emul, int reg, uint8_t val); /** * @brief Get value of given register of BMI * * @param emul Pointer to BMI emulator * @param reg Register address * * @return Value of the register */ uint8_t bmi_emul_get_reg(struct i2c_emul *emul, int reg); /** * @brief Get internal value of offset for given axis and sensor * * @param emul Pointer to BMI emulator * @param axis Axis to access * * @return Offset of given axis. LSB for accelerometer is 0.061mg and for * gyroscope is 0.0037°/s. */ int16_t bmi_emul_get_off(struct i2c_emul *emul, enum bmi_emul_axis axis); /** * @brief Set internal value of offset for given axis and sensor * * @param emul Pointer to BMI emulator * @param axis Axis to access * @param val New value of given axis. LSB for accelerometer is 0.061mg and for * gyroscope is 0.0037°/s. */ void bmi_emul_set_off(struct i2c_emul *emul, enum bmi_emul_axis axis, int16_t val); /** * @brief Get internal value of sensor for given axis * * @param emul Pointer to BMI emulator * @param axis Axis to access * * @return Sensor value of given axis. LSB for accelerometer is 0.061mg and for * gyroscope is 0.0037°/s. */ int32_t bmi_emul_get_value(struct i2c_emul *emul, enum bmi_emul_axis axis); /** * @brief Set internal value of sensor for given axis * * @param emul Pointer to BMI emulator * @param axis Axis to access * @param val New value of given axis. LSB for accelerometer is 0.061mg and for * gyroscope is 0.0037°/s. */ void bmi_emul_set_value(struct i2c_emul *emul, enum bmi_emul_axis axis, int32_t val); /** * @brief Set if error should be generated when read only register is being * written * * @param emul Pointer to BMI emulator * @param set Check for this error */ void bmi_emul_set_err_on_ro_write(struct i2c_emul *emul, bool set); /** * @brief Set if error should be generated when reserved bits of register are * not set to 0 on write I2C message * * @param emul Pointer to BMI emulator * @param set Check for this error */ void bmi_emul_set_err_on_rsvd_write(struct i2c_emul *emul, bool set); /** * @brief Set if error should be generated when write only register is read * * @param emul Pointer to BMI emulator * @param set Check for this error */ void bmi_emul_set_err_on_wo_read(struct i2c_emul *emul, bool set); /** * @brief Set if effect of simulated command should take place after simulated * time pass from issuing command. * * @param emul Pointer to BMI emulator * @param set Simulate command execution time */ void bmi_emul_simulate_cmd_exec_time(struct i2c_emul *emul, bool set); /** * @brief Set number of skipped frames. It will generate skip frame on next * access to FIFO. After that number of skipped frames is reset to 0. * * @param emul Pointer to BMI emulator * @param skip Number of skipped frames */ void bmi_emul_set_skipped_frames(struct i2c_emul *emul, uint8_t skip); /** * @brief Clear all FIFO frames, set current frame to empty and reset fifo_skip * counter * * @param emul Pointer to BMI emulator * @param tag_time Indicate if sensor time should be included in empty frame * @param header Indicate if header should be included in frame */ void bmi_emul_flush_fifo(struct i2c_emul *emul, bool tag_time, bool header); /** * @brief Restore registers backed by NVM, reset sensor time and flush FIFO * * @param emul Pointer to BMI emulator */ void bmi_emul_reset_common(struct i2c_emul *emul, bool tag_time, bool header); /** * @brief Set command end time to @p time ms from now * * @param emul Pointer to BMI emulator * @param time After this amount of ms command should end */ void bmi_emul_set_cmd_end_time(struct i2c_emul *emul, int time); /** * @brief Check if command should end * * @param emul Pointer to BMI emulator */ bool bmi_emul_is_cmd_end(struct i2c_emul *emul); /** * @brief Append FIFO @p frame to the emulator list of frames. It can be read * using I2C interface. * * @param emul Pointer to BMI emulator * @param frame Pointer to new FIFO frame. Pointed data has to be valid while * emulator may use this frame (until flush of FIFO or reading * it out through I2C) */ void bmi_emul_append_frame(struct i2c_emul *emul, struct bmi_emul_frame *frame); /** * @brief Get length of all frames that are on the emulator list of frames. * * @param emul Pointer to BMI emulator * @param tag_time Indicate if sensor time should be included in empty frame * @param header Indicate if header should be included in frame */ uint16_t bmi_emul_fifo_len(struct i2c_emul *emul, bool tag_time, bool header); /** * @brief Get next byte that should be returned on FIFO data access. * * @param emul Pointer to BMI emulator * @param byte Which byte of block read command is currently handled * @param tag_time Indicate if sensor time should be included in empty frame * @param header Indicate if header should be included in frame * @param acc_shift How many bits should be right shifted from accelerometer * data * @param gyr_shift How many bits should be right shifted from gyroscope data * * @return FIFO data byte */ uint8_t bmi_emul_get_fifo_data(struct i2c_emul *emul, int byte, bool tag_time, bool header, int acc_shift, int gyr_shift); /** * @brief Saves current internal state of sensors to emulator's registers. * * @param emul Pointer to BMI emulator * @param acc_shift How many bits should be right shifted from accelerometer * data * @param gyr_shift How many bits should be right shifted from gyroscope data * @param acc_reg Register which holds LSB of accelerometer sensor * @param gyr_reg Register which holds LSB of gyroscope sensor * @param sensortime_reg Register which holds LSB of sensor time * @param acc_off_en Indicate if accelerometer offset should be included to * sensor data value * @param gyr_off_en Indicate if gyroscope offset should be included to * sensor data value */ void bmi_emul_state_to_reg(struct i2c_emul *emul, int acc_shift, int gyr_shift, int acc_reg, int gyr_reg, int sensortime_reg, bool acc_off_en, bool gyr_off_en); /** * @} */ #endif /* __EMUL_BMI_H */