inv_icm42600_buffer.h

  1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/*
  3 * Copyright (C) 2020 Invensense, Inc.
  4 */
  5
  6#ifndef INV_ICM42600_BUFFER_H_
  7#define INV_ICM42600_BUFFER_H_
  8
  9#include <linux/kernel.h>
 10#include <linux/bits.h>
 11
 12struct inv_icm42600_state;
 13
 14#define INV_ICM42600_SENSOR_GYRO	BIT(0)
 15#define INV_ICM42600_SENSOR_ACCEL	BIT(1)
 16#define INV_ICM42600_SENSOR_TEMP	BIT(2)
 17
 18/**
 19 * struct inv_icm42600_fifo - FIFO state variables
 20 * @on:		reference counter for FIFO on.
 21 * @en:		bits field of INV_ICM42600_SENSOR_* for FIFO EN bits.
 22 * @period:	FIFO internal period.
 23 * @watermark:	watermark configuration values for accel and gyro.
 24 * @count:	number of bytes in the FIFO data buffer.
 25 * @nb:		gyro, accel and total samples in the FIFO data buffer.
 26 * @data:	FIFO data buffer aligned for DMA (2kB + 32 bytes of read cache).
 27 */
 28struct inv_icm42600_fifo {
 29	unsigned int on;
 30	unsigned int en;
 31	u32 period;
 32	struct {
 33		unsigned int gyro;
 34		unsigned int accel;
 35		unsigned int eff_gyro;
 36		unsigned int eff_accel;
 37	} watermark;
 38	size_t count;
 39	struct {
 40		size_t gyro;
 41		size_t accel;
 42		size_t total;
 43	} nb;
 44	u8 data[2080] __aligned(IIO_DMA_MINALIGN);
 45};
 46
 47/* FIFO data packet */
 48struct inv_icm42600_fifo_sensor_data {
 49	__be16 x;
 50	__be16 y;
 51	__be16 z;
 52} __packed;
 53#define INV_ICM42600_FIFO_DATA_INVALID		-32768
 54
 55static inline s16 inv_icm42600_fifo_get_sensor_data(__be16 d)
 56{
 57	return be16_to_cpu(d);
 58}
 59
 60static inline bool
 61inv_icm42600_fifo_is_data_valid(const struct inv_icm42600_fifo_sensor_data *s)
 62{
 63	s16 x, y, z;
 64
 65	x = inv_icm42600_fifo_get_sensor_data(s->x);
 66	y = inv_icm42600_fifo_get_sensor_data(s->y);
 67	z = inv_icm42600_fifo_get_sensor_data(s->z);
 68
 69	if (x == INV_ICM42600_FIFO_DATA_INVALID &&
 70	    y == INV_ICM42600_FIFO_DATA_INVALID &&
 71	    z == INV_ICM42600_FIFO_DATA_INVALID)
 72		return false;
 73
 74	return true;
 75}
 76
 77ssize_t inv_icm42600_fifo_decode_packet(const void *packet, const void **accel,
 78					const void **gyro, const s8 **temp,
 79					const void **timestamp, unsigned int *odr);
 80
 81extern const struct iio_buffer_setup_ops inv_icm42600_buffer_ops;
 82
 83int inv_icm42600_buffer_init(struct inv_icm42600_state *st);
 84
 85void inv_icm42600_buffer_update_fifo_period(struct inv_icm42600_state *st);
 86
 87int inv_icm42600_buffer_set_fifo_en(struct inv_icm42600_state *st,
 88				    unsigned int fifo_en);
 89
 90int inv_icm42600_buffer_update_watermark(struct inv_icm42600_state *st);
 91
 92int inv_icm42600_buffer_fifo_read(struct inv_icm42600_state *st,
 93				  unsigned int max);
 94
 95int inv_icm42600_buffer_fifo_parse(struct inv_icm42600_state *st);
 96
 97int inv_icm42600_buffer_hwfifo_flush(struct inv_icm42600_state *st,
 98				     unsigned int count);
 99
100#endif