iio: health: Add driver for the TI AFE4403 heart monitor

Add driver for the TI AFE4403 heart rate monitor and pulse oximeter.
This device detects reflected LED light fluctuations and presents an ADC
value to the user space for further signal processing.

Data sheet located here:
http://www.ti.com/product/AFE4403/datasheet

Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/health/Kconfig

@@ -7,6 +7,18 @@ menu "Health Sensors"
 
 menu "Heart Rate Monitors"
 
+config AFE4403
+	tristate "TI AFE4403 Heart Rate Monitor"
+	depends on SPI_MASTER
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	help
+	  Say yes to choose the Texas Instruments AFE4403
+	  heart rate monitor and low-cost pulse oximeter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called afe4403.
+
 config AFE4404
 	tristate "TI AFE4404 heart rate and pulse oximeter sensor"
 	depends on I2C

drivers/iio/health/Makefile

@@ -4,5 +4,6 @@
 
 # When adding new entries keep the list in alphabetical order
 
+obj-$(CONFIG_AFE4403)		+= afe4403.o
 obj-$(CONFIG_AFE4404)		+= afe4404.o
 obj-$(CONFIG_MAX30100)		+= max30100.o