iio: envelope-detector: ADC driver based on a DAC and a comparator

The DAC is used to find the peak level of an alternating voltage input
signal by a binary search using the output of a comparator wired to
an interrupt pin. Like so:
                          _
                         | \
    input +------>-------|+ \
                         |   \
           .-------.     |    }---.
           |       |     |   /    |
           |    dac|-->--|- /     |
           |       |     |_/      |
           |       |              |
           |       |              |
           |    irq|------<-------'
           |       |
           '-------'

Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 76c3124fd62f..0393f1f1bee7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6131,7 +6131,9 @@ IIO ENVELOPE DETECTOR
 M:      Peter Rosin <peda@axentia.se>
 L:      linux-iio@vger.kernel.org
 S:      Maintained
+F:      Documentation/ABI/testing/sysfs-bus-iio-adc-envelope-detector
 F:      Documentation/devicetree/bindings/iio/adc/envelope-detector.txt
+F:      drivers/iio/adc/envelope-detector.c
 
 IIO SUBSYSTEM AND DRIVERS
 M:      Jonathan Cameron <jic23@kernel.org>