1 files changed, 98 insertions, 0 deletions
diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_buffer.h b/drivers/iio/imu/inv_icm42600/inv_icm42600_buffer.h
new file mode 100644
index 000000000..de2a3949d
--- /dev/null
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_buffer.h
@@ -0,0 +1,98 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2020 Invensense, Inc.
+ */
+
+#ifndef INV_ICM42600_BUFFER_H_
+#define INV_ICM42600_BUFFER_H_
+
+#include <linux/kernel.h>
+#include <linux/bits.h>
+
+struct inv_icm42600_state;
+
+#define INV_ICM42600_SENSOR_GYRO	BIT(0)
+#define INV_ICM42600_SENSOR_ACCEL	BIT(1)
+#define INV_ICM42600_SENSOR_TEMP	BIT(2)
+
+/**
+ * struct inv_icm42600_fifo - FIFO state variables
+ * @on:		reference counter for FIFO on.
+ * @en:		bits field of INV_ICM42600_SENSOR_* for FIFO EN bits.
+ * @period:	FIFO internal period.
+ * @watermark:	watermark configuration values for accel and gyro.
+ * @count:	number of bytes in the FIFO data buffer.
+ * @nb:		gyro, accel and total samples in the FIFO data buffer.
+ * @data:	FIFO data buffer aligned for DMA (2kB + 32 bytes of read cache).
+ */
+struct inv_icm42600_fifo {
+	unsigned int on;
+	unsigned int en;
+	uint32_t period;
+	struct {
+		unsigned int gyro;
+		unsigned int accel;
+	} watermark;
+	size_t count;
+	struct {
+		size_t gyro;
+		size_t accel;
+		size_t total;
+	} nb;
+	uint8_t data[2080] ____cacheline_aligned;
+};
+
+/* FIFO data packet */
+struct inv_icm42600_fifo_sensor_data {
+	__be16 x;
+	__be16 y;
+	__be16 z;
+} __packed;
+#define INV_ICM42600_FIFO_DATA_INVALID		-32768
+
+static inline int16_t inv_icm42600_fifo_get_sensor_data(__be16 d)
+{
+	return be16_to_cpu(d);
+}
+
+static inline bool
+inv_icm42600_fifo_is_data_valid(const struct inv_icm42600_fifo_sensor_data *s)
+{
+	int16_t x, y, z;
+
+	x = inv_icm42600_fifo_get_sensor_data(s->x);
+	y = inv_icm42600_fifo_get_sensor_data(s->y);
+	z = inv_icm42600_fifo_get_sensor_data(s->z);
+
+	if (x == INV_ICM42600_FIFO_DATA_INVALID &&
+	    y == INV_ICM42600_FIFO_DATA_INVALID &&
+	    z == INV_ICM42600_FIFO_DATA_INVALID)
+		return false;
+
+	return true;
+}
+
+ssize_t inv_icm42600_fifo_decode_packet(const void *packet, const void **accel,
+					const void **gyro, const int8_t **temp,
+					const void **timestamp, unsigned int *odr);
+
+extern const struct iio_buffer_setup_ops inv_icm42600_buffer_ops;
+
+int inv_icm42600_buffer_init(struct inv_icm42600_state *st);
+
+void inv_icm42600_buffer_update_fifo_period(struct inv_icm42600_state *st);
+
+int inv_icm42600_buffer_set_fifo_en(struct inv_icm42600_state *st,
+				    unsigned int fifo_en);
+
+int inv_icm42600_buffer_update_watermark(struct inv_icm42600_state *st);
+
+int inv_icm42600_buffer_fifo_read(struct inv_icm42600_state *st,
+				  unsigned int max);
+
+int inv_icm42600_buffer_fifo_parse(struct inv_icm42600_state *st);
+
+int inv_icm42600_buffer_hwfifo_flush(struct inv_icm42600_state *st,
+				     unsigned int count);
+
+#endif