icm42688: RTIO device for streaming

An experimental idea to enable streaming fifo data from the sensor using
RTIO with the existing sensor API. A sensor reader could easily be built on
top of the buffer to produce meaningful values.

There are many ways this can be built currently. Using either the existing
trigger work context (system workqueue or own thread) when SPI_RTIO=n or
using a sequence. With or without SPI_SAM_DMA (where only polling SPI
transfers are used).

This is a really nice setup to explore and experiment with RTIO, SPI, and
a really fast sensor.

Signed-off-by: Tom Burdick <[email protected]>

Author: teburd

drivers/sensor/icm42688/Kconfig

@@ -4,6 +4,8 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
+DT_COMPAT_ICM42688 := invensense,icm42688
+
 config ICM42688
 	bool "ICM42688 Six-Axis Motion Tracking Device"
 	default y
@@ -58,4 +60,10 @@ config ICM42688_THREAD_STACK_SIZE
 	help
 	  The thread stack size.
 
+config ICM42688_RTIO
+	bool "ICM42688 RTIO Support"
+	depends on RTIO
+	help
+	  Enable RTIO support for ICM42688 allowing for scatter gather like requests against the fifo.
+
 endif # ICM42688