KX022A is a 3-axis accelerometer from ROHM/Kionix. The sensor features
include variable ODRs, I2C and SPI control, FIFO/LIFO with watermark IRQ,
tap/motion detection, wake-up & back-to-sleep events, four acceleration
ranges (2, 4, 8 and 16g), and probably some other cool features.
Add support for the basic accelerometer features such as getting the
acceleration data via IIO. (raw reads, triggered buffer [data-ready] or
using the WMI IRQ).
Important things to be added include the double-tap, motion
detection and wake-up as well as the runtime power management.
Signed-off-by: Matti Vaittinen <mazziesaccount-Re5JQEeQqe8AvxtiuMwx3w@xxxxxxxxxxxxxxxx>
---
+/*
+ * The KX022A has FIFO which can store 43 samples of HiRes data from 2
+ * channels. This equals to 43 (samples) * 3 (channels) * 2 (bytes/sample) to
+ * 258 bytes of sample data. The quirk to know is that the amount of bytes in
+ * the FIFO is advertised via 8 bit register (max value 255). The thing to note
+ * is that full 258 bytes of data is indicated using the max value 255.
+ */