dt-bindings: iio: adc: adi,ad7606: improve descriptions

Reword a few descriptions, and normalize the text width to 80 characters.
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Guillaume Stols <gstols@baylibre.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/adc/adi,ad7606.yaml

@@ -36,6 +36,9 @@ properties:
   avcc-supply: true
 
   interrupts:
+    description:
+      The BUSY pin falling edge indicates that the conversion is over, and thus
+      new data is available.
     maxItems: 1
 
   adi,conversion-start-gpios:
@@ -48,8 +51,9 @@ properties:
   reset-gpios:
     description:
       Must be the device tree identifier of the RESET pin. If specified, it will
-      be asserted during driver probe. As the line is active high, it should be
-      marked GPIO_ACTIVE_HIGH.
+      be asserted during driver probe. On the AD7606x, as the line is active
+      high, it should be marked GPIO_ACTIVE_HIGH. On the AD7616, as the line is
+      active low, it should be marked GPIO_ACTIVE_LOW.
     maxItems: 1
 
   standby-gpios:
@@ -62,36 +66,39 @@ properties:
 
   adi,first-data-gpios:
     description:
-      Must be the device tree identifier of the FRSTDATA pin.  The FRSTDATA
+      Must be the device tree identifier of the FRSTDATA pin. The FRSTDATA
       output indicates when the first channel, V1, is being read back on either
-      the parallel, byte or serial interface.  As the line is active high, it
+      the parallel, byte or serial interface. As the line is active high, it
       should be marked GPIO_ACTIVE_HIGH.
     maxItems: 1
 
   adi,range-gpios:
     description:
-      Must be the device tree identifier of the RANGE pin. The polarity on this
+      Must be the device tree identifier of the RANGE pin. The state on this
       pin determines the input range of the analog input channels. If this pin
       is tied to a logic high, the analog input range is ±10V for all channels.
-      If this pin is tied to a logic low, the analog input range is ±5V for all
-      channels. As the line is active high, it should be marked
+      On the AD760X, if this pin is tied to a logic low, the analog input range
+      is ±5V for all channels. As the line is active high, it should be marked
       GPIO_ACTIVE_HIGH.
     maxItems: 1
 
   adi,oversampling-ratio-gpios:
     description:
       Must be the device tree identifier of the over-sampling mode pins. As the
-      line is active high, it should be marked GPIO_ACTIVE_HIGH.
+      line is active high, it should be marked GPIO_ACTIVE_HIGH. On the AD7606X
+      parts that support it, if all 3 pins are tied to a logic high, software
+      mode is enabled.
     maxItems: 3
 
   adi,sw-mode:
     description:
-      Software mode of operation, so far available only for ad7616 and ad7606b.
+      Software mode of operation, so far available only for AD7616 and AD7606B.
       It is enabled when all three oversampling mode pins are connected to high
-      level. The device is configured by the corresponding registers. If the
-      adi,oversampling-ratio-gpios property is defined, then the driver will set
-      the oversampling gpios to high. Otherwise, it is assumed that the pins are
-      hardwired to VDD.
+      level for the AD7606B, or both the range selection are connected to high
+      level for the AD7616. The device is configured by the corresponding
+      registers. If the adi,oversampling-ratio-gpios property is defined, then
+      the driver will set the oversampling gpios to high. Otherwise, it is
+      assumed that the pins are hardwired to VDD.
     type: boolean
 
 required: