iio:pressure: initial zpa2326 barometer support

Introduce driver for Murata ZPA2326 pressure and temperature sensor:
http://www.murata.com/en-us/products/productdetail?partno=ZPA2326-0311A-R

Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Documentation/devicetree/bindings/iio/pressure/zpa2326.txt

@@ -0,0 +1,31 @@
+Murata ZPA2326 pressure sensor
+
+Pressure sensor from Murata with SPI and I2C bus interfaces.
+
+Required properties:
+- compatible: "murata,zpa2326"
+- reg: the I2C address or SPI chip select the device will respond to
+
+Recommended properties for SPI bus usage:
+- spi-max-frequency: maximum SPI bus frequency as documented in
+  Documentation/devicetree/bindings/spi/spi-bus.txt
+
+Optional properties:
+- vref-supply: an optional regulator that needs to be on to provide VREF
+  power to the sensor
+- vdd-supply: an optional regulator that needs to be on to provide VDD
+  power to the sensor
+- interrupt-parent: phandle to the parent interrupt controller as documented in
+  Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+- interrupts: interrupt mapping for IRQ as documented in
+  Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+
+Example:
+
+zpa2326@5c {
+	compatible = "murata,zpa2326";
+	reg = <0x5c>;
+	interrupt-parent = <&gpio>;
+	interrupts = <12>;
+	vdd-supply = <&ldo_1v8_gnss>;
+};

drivers/iio/pressure/Kconfig

@@ -187,4 +187,26 @@ config HP206C
 	  This driver can also be built as a module. If so, the module will
 	  be called hp206c.
 
+config ZPA2326
+	tristate "Murata ZPA2326 pressure sensor driver"
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	select REGMAP
+	select ZPA2326_I2C if I2C
+	select ZPA2326_SPI if SPI_MASTER
+	help
+	  Say Y here to build support for the Murata ZPA2326 pressure and
+	  temperature sensor.
+
+	  To compile this driver as a module, choose M here: the module will
+	  be called zpa2326.
+
+config ZPA2326_I2C
+	tristate
+	select REGMAP_I2C
+
+config ZPA2326_SPI
+	tristate
+	select REGMAP_SPI
+
 endmenu

drivers/iio/pressure/Makefile

@@ -22,6 +22,9 @@ st_pressure-y := st_pressure_core.o
 st_pressure-$(CONFIG_IIO_BUFFER) += st_pressure_buffer.o
 obj-$(CONFIG_T5403) += t5403.o
 obj-$(CONFIG_HP206C) += hp206c.o
+obj-$(CONFIG_ZPA2326) += zpa2326.o
+obj-$(CONFIG_ZPA2326_I2C) += zpa2326_i2c.o
+obj-$(CONFIG_ZPA2326_SPI) += zpa2326_spi.o
 
 obj-$(CONFIG_IIO_ST_PRESS_I2C) += st_pressure_i2c.o
 obj-$(CONFIG_IIO_ST_PRESS_SPI) += st_pressure_spi.o