drivers/iio/imu/inv_icm42600/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
  12 struct 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  */
  28 struct 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] ____cacheline_aligned;
  43 };
  44
  45 /* FIFO data packet */
  46 struct 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
  53 static inline int16_t inv_icm42600_fifo_get_sensor_data(__be16 d)
  54 {
  55         return be16_to_cpu(d);
  56 }
  57
  58 static inline bool
  59 inv_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
  75 ssize_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
  79 extern const struct iio_buffer_setup_ops inv_icm42600_buffer_ops;
  80
  81 int inv_icm42600_buffer_init(struct inv_icm42600_state *st);
  82
  83 void inv_icm42600_buffer_update_fifo_period(struct inv_icm42600_state *st);
  84
  85 int inv_icm42600_buffer_set_fifo_en(struct inv_icm42600_state *st,
  86                                     unsigned int fifo_en);
  87
  88 int inv_icm42600_buffer_update_watermark(struct inv_icm42600_state *st);
  89
  90 int inv_icm42600_buffer_fifo_read(struct inv_icm42600_state *st,
  91                                   unsigned int max);
  92
  93 int inv_icm42600_buffer_fifo_parse(struct inv_icm42600_state *st);
  94
  95 int inv_icm42600_buffer_hwfifo_flush(struct inv_icm42600_state *st,
  96                                      unsigned int count);
  97
  98 #endif