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                 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         uint8_t data[2080] __aligned(IIO_DMA_MINALIGN);
  45 };
  46
  47 /* FIFO data packet */
  48 struct 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
  55 static inline int16_t inv_icm42600_fifo_get_sensor_data(__be16 d)
  56 {
  57         return be16_to_cpu(d);
  58 }
  59
  60 static inline bool
  61 inv_icm42600_fifo_is_data_valid(const struct inv_icm42600_fifo_sensor_data *s)
  62 {
  63         int16_t 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
  77 ssize_t inv_icm42600_fifo_decode_packet(const void *packet, const void **accel,
  78                                         const void **gyro, const int8_t **temp,
  79                                         const void **timestamp, unsigned int *odr);
  80
  81 extern const struct iio_buffer_setup_ops inv_icm42600_buffer_ops;
  82
  83 int inv_icm42600_buffer_init(struct inv_icm42600_state *st);
  84
  85 void inv_icm42600_buffer_update_fifo_period(struct inv_icm42600_state *st);
  86
  87 int inv_icm42600_buffer_set_fifo_en(struct inv_icm42600_state *st,
  88                                     unsigned int fifo_en);
  89
  90 int inv_icm42600_buffer_update_watermark(struct inv_icm42600_state *st);
  91
  92 int inv_icm42600_buffer_fifo_read(struct inv_icm42600_state *st,
  93                                   unsigned int max);
  94
  95 int inv_icm42600_buffer_fifo_parse(struct inv_icm42600_state *st);
  96
  97 int inv_icm42600_buffer_hwfifo_flush(struct inv_icm42600_state *st,
  98                                      unsigned int count);
  99
 100 #endif