iio:cdc:ad7150: Move driver out of staging.

This capacitance to digital converter (CDC) driver is compliant with
the IIO ABI.  Note, not all features supported (e.g. window event modes)
but the driver should be in a useful functional state.

The cleanup was done against QEMU emulation of the device rather than
actual hardware.   Whilst this was a bit of an experiment, it made it
easy to confirm that the driver remained in a consistent working state
through the various refactors.  If it worked in the first place, it
should still be working after this cleanup.

Given some IIO drivers require expensive hardware setups, (not particularly
true with this one) the use of QEMU may provide a viable way forward
for providing testing during code changes where previously we'd had
to rely on sharp eyes and crossed fingers.

Note, no explicit MAINTAINERS entry as it will be covered by the
generic catch-alls for ADI and IIO drivers which are sufficient.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210314181511.531414-25-jic23@kernel.org

7 files changed, 26 insertions, 12 deletions

diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig
index b35e0c33b5e2..2334ad249b46 100644
--- a/drivers/iio/Kconfig
+++ b/drivers/iio/Kconfig
@@ -72,6 +72,7 @@ source "drivers/iio/accel/Kconfig"
 source "drivers/iio/adc/Kconfig"
 source "drivers/iio/afe/Kconfig"
 source "drivers/iio/amplifiers/Kconfig"
+source "drivers/iio/cdc/Kconfig"
 source "drivers/iio/chemical/Kconfig"
 source "drivers/iio/common/Kconfig"
 source "drivers/iio/dac/Kconfig"
diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
index 2561325aaa74..65e39bd4f934 100644
--- a/drivers/iio/Makefile
+++ b/drivers/iio/Makefile
@@ -18,6 +18,7 @@ obj-y += adc/
 obj-y += afe/
 obj-y += amplifiers/
 obj-y += buffer/
+obj-y += cdc/
 obj-y += chemical/
 obj-y += common/
 obj-y += dac/
diff --git a/drivers/iio/cdc/Kconfig b/drivers/iio/cdc/Kconfig
new file mode 100644
index 000000000000..5e3319a3ff48
--- /dev/null
+++ b/drivers/iio/cdc/Kconfig
@@ -0,0 +1,17 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# CDC drivers
+#
+menu "Capacitance to digital converters"
+
+config AD7150
+	tristate "Analog Devices ad7150/1/6 capacitive sensor driver"
+	depends on I2C
+	help
+	  Say yes here to build support for Analog Devices capacitive sensors.
+	  (ad7150, ad7151, ad7156) Provides direct access via sysfs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ad7150.
+
+endmenu
diff --git a/drivers/iio/cdc/Makefile b/drivers/iio/cdc/Makefile
new file mode 100644
index 000000000000..ee490637b032
--- /dev/null
+++ b/drivers/iio/cdc/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for industrial I/O capacitance to digital converter (CDC) drivers
+#
+
+obj-$(CONFIG_AD7150) += ad7150.o
diff --git a/drivers/staging/iio/cdc/ad7150.c b/drivers/iio/cdc/ad7150.c
index f9cce1a64586..f9cce1a64586 100644
--- a/drivers/staging/iio/cdc/ad7150.c
+++ b/drivers/iio/cdc/ad7150.c
diff --git a/drivers/staging/iio/cdc/Kconfig b/drivers/staging/iio/cdc/Kconfig
index e0a5ce66a984..a7386bbbcb79 100644
--- a/drivers/staging/iio/cdc/Kconfig
+++ b/drivers/staging/iio/cdc/Kconfig
@@ -4,16 +4,6 @@
 #
 menu "Capacitance to digital converters"
 
-config AD7150
-	tristate "Analog Devices ad7150/1/6 capacitive sensor driver"
-	depends on I2C
-	help
-	  Say yes here to build support for Analog Devices capacitive sensors.
-	  (ad7150, ad7151, ad7156) Provides direct access via sysfs.
-
-	  To compile this driver as a module, choose M here: the
-	  module will be called ad7150.
-
 config AD7746
 	tristate "Analog Devices AD7745, AD7746 AD7747 capacitive sensor driver"
 	depends on I2C
diff --git a/drivers/staging/iio/cdc/Makefile b/drivers/staging/iio/cdc/Makefile
index ab8222579e7e..afb7499a7090 100644
--- a/drivers/staging/iio/cdc/Makefile
+++ b/drivers/staging/iio/cdc/Makefile
@@ -1,7 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 #
-# Makefile for industrial I/O DAC drivers
+# Makefile for industrial I/O CDC drivers
 #
 
-obj-$(CONFIG_AD7150) += ad7150.o
 obj-$(CONFIG_AD7746) += ad7746.o