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	uint32_t period;
32	struct {
33		unsigned int gyro;
34		unsigned int accel;
35	} watermark;
36	size_t count;
37	struct {
38		size_t gyro;
39		size_t accel;
40		size_t total;
41	} nb;
42	uint8_t data[2080] __aligned(IIO_DMA_MINALIGN);
43};
44
45/* FIFO data packet */
46struct inv_icm42600_fifo_sensor_data {
47	__be16 x;
48	__be16 y;
49	__be16 z;
50} __packed;
51#define INV_ICM42600_FIFO_DATA_INVALID		-32768
52
53static inline int16_t inv_icm42600_fifo_get_sensor_data(__be16 d)
54{
55	return be16_to_cpu(d);
56}
57
58static inline bool
59inv_icm42600_fifo_is_data_valid(const struct inv_icm42600_fifo_sensor_data *s)
60{
61	int16_t x, y, z;
62
63	x = inv_icm42600_fifo_get_sensor_data(s->x);
64	y = inv_icm42600_fifo_get_sensor_data(s->y);
65	z = inv_icm42600_fifo_get_sensor_data(s->z);
66
67	if (x == INV_ICM42600_FIFO_DATA_INVALID &&
68	    y == INV_ICM42600_FIFO_DATA_INVALID &&
69	    z == INV_ICM42600_FIFO_DATA_INVALID)
70		return false;
71
72	return true;
73}
74
75ssize_t inv_icm42600_fifo_decode_packet(const void *packet, const void **accel,
76					const void **gyro, const int8_t **temp,
77					const void **timestamp, unsigned int *odr);
78
79extern const struct iio_buffer_setup_ops inv_icm42600_buffer_ops;
80
81int inv_icm42600_buffer_init(struct inv_icm42600_state *st);
82
83void inv_icm42600_buffer_update_fifo_period(struct inv_icm42600_state *st);
84
85int inv_icm42600_buffer_set_fifo_en(struct inv_icm42600_state *st,
86				    unsigned int fifo_en);
87
88int inv_icm42600_buffer_update_watermark(struct inv_icm42600_state *st);
89
90int inv_icm42600_buffer_fifo_read(struct inv_icm42600_state *st,
91				  unsigned int max);
92
93int inv_icm42600_buffer_fifo_parse(struct inv_icm42600_state *st);
94
95int inv_icm42600_buffer_hwfifo_flush(struct inv_icm42600_state *st,
96				     unsigned int count);
97
98#endif
99