iio: adc: ad4630: Add output mode for ADAQ4216 and ADAQ4220

The IIO channels are defined according to the output mode and for each
output mode the precision bits is set statically in the output mode struct.
Due to static assignment of channel precision bits in output mode structs,
new output mode structs need to be declared for devices that
have different amount of precision bits.
Maybe we can have less code duplication if the precision bits for each
ADC can be retrieved (maybe from devicetree?, static table?) then used for
output mode declaration.
For now, add output mode structs for ADAQ4216 and ADAQ4220 which are equal
to ADAQ4224 except for they have different precision and don't have
24-bit + 8-bit common mode.

Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>

Author: machschmitt

drivers/iio/adc/ad4630.c

@@ -893,6 +893,48 @@ static const struct ad4630_out_mode ad4630_24_modes[] = {
 	}
 };
 
+static const struct ad4630_out_mode adaq4216_modes[] = {
+	[AD4630_16_DIFF] = {
+		.channels = {
+			AD4630_CHAN(0, BIT(IIO_CHAN_INFO_SCALE), 64, 16, 0, NULL),
+		},
+		.data_width = 16,
+	},
+	[AD4630_16_DIFF_8_COM] = {
+		.channels = {
+			AD4630_CHAN(0, BIT(IIO_CHAN_INFO_SCALE), 64, 16, 8, NULL),
+		},
+		.data_width = 24,
+	},
+	[AD4630_30_AVERAGED_DIFF] = {
+		.channels = {
+			AD4630_CHAN(0, BIT(IIO_CHAN_INFO_SCALE), 64, 30, 2, ad4630_ext_info),
+		},
+		.data_width = 32,
+	}
+};
+
+static const struct ad4630_out_mode adaq4220_modes[] = {
+	[AD4630_16_DIFF] = {
+		.channels = {
+			AD4630_CHAN(0, BIT(IIO_CHAN_INFO_SCALE), 64, 20, 0, NULL),
+		},
+		.data_width = 20,
+	},
+	[AD4630_16_DIFF_8_COM] = {
+		.channels = {
+			AD4630_CHAN(0, BIT(IIO_CHAN_INFO_SCALE), 64, 16, 8, NULL),
+		},
+		.data_width = 24,
+	},
+	[AD4630_30_AVERAGED_DIFF] = {
+		.channels = {
+			AD4630_CHAN(0, BIT(IIO_CHAN_INFO_SCALE), 64, 30, 2, ad4630_ext_info),
+		},
+		.data_width = 32,
+	}
+};
+
 static const struct ad4630_out_mode adaq4224_modes[] = {
 	[AD4630_24_DIFF] = {
 		.channels = {
@@ -1000,7 +1042,7 @@ static const struct ad4630_chip_info ad4630_chip_info[] = {
 	},
 	[ID_ADAQ4216] = {
 		.available_masks = ad4030_channel_masks,
-		.modes = adaq4224_modes,
+		.modes = adaq4216_modes,
 		.out_modes_mask = GENMASK(3, 0),
 		.name = "adaq4216",
 		.grade = 0x1E,
@@ -1012,7 +1054,7 @@ static const struct ad4630_chip_info ad4630_chip_info[] = {
 	},
 	[ID_ADAQ4220] = {
 		.available_masks = ad4030_channel_masks,
-		.modes = adaq4224_modes,
+		.modes = adaq4220_modes,
 		.out_modes_mask = GENMASK(3, 0),
 		.name = "adaq4220",
 		.grade = 0x1D,