[PATCH 1/2] iio: amplifiers: adrf5740: Add Support ADRF5740 4-bit Attenuator

[Ana-Maria Cusco]

From: Ana-Maria Cusco <ana-maria.cusco@xxxxxxxxxx>

This adds support for the Analog Devices ADRF5740 2 dB LSB, 4-Bit,
Silicon Digital Attenuator, 10 MHz to 60 GHz

Signed-off-by: Ana-Maria Cusco <ana-maria.cusco@xxxxxxxxxx>
---
 drivers/iio/amplifiers/hmc425a.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/iio/amplifiers/hmc425a.c b/drivers/iio/amplifiers/hmc425a.c
index e87d35d50a95..ed4d72922696 100644
--- a/drivers/iio/amplifiers/hmc425a.c
+++ b/drivers/iio/amplifiers/hmc425a.c
@@ -5,6 +5,7 @@
  * Copyright 2020 Analog Devices Inc.
  */
 
+#include <linux/bitops.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/gpio/consumer.h>
@@ -22,6 +23,7 @@
 enum hmc425a_type {
 	ID_HMC425A,
 	ID_HMC540S,
+	ID_ADRF5740
 };
 
 struct hmc425a_chip_info {
@@ -74,6 +76,10 @@ static int hmc425a_read_raw(struct iio_dev *indio_dev,
 		case ID_HMC540S:
 			gain = ~code * -1000;
 			break;
+		case ID_ADRF5740:
+			code = code & BIT(3) ? code & ~BIT(2) : code;
+			gain = code * -2000;
+			break;
 		}
 
 		*val = gain / 1000;
@@ -113,6 +119,10 @@ static int hmc425a_write_raw(struct iio_dev *indio_dev,
 	case ID_HMC540S:
 		code = ~((abs(gain) / 1000) & 0xF);
 		break;
+	case ID_ADRF5740:
+		code = (abs(gain) / 2000) & 0xF;
+		code = code & BIT(3) ? code | BIT(2) : code;
+		break;
 	}
 
 	mutex_lock(&st->lock);
@@ -165,6 +175,7 @@ static const struct iio_chan_spec hmc425a_channels[] = {
 static const struct of_device_id hmc425a_of_match[] = {
 	{ .compatible = "adi,hmc425a", .data = (void *)ID_HMC425A },
 	{ .compatible = "adi,hmc540s", .data = (void *)ID_HMC540S },
+	{ .compatible = "adi,adrf5740", .data = (void *)ID_ADRF5740 },
 	{},
 };
 MODULE_DEVICE_TABLE(of, hmc425a_of_match);
@@ -188,6 +199,15 @@ static struct hmc425a_chip_info hmc425a_chip_info_tbl[] = {
 		.gain_max = 0,
 		.default_gain = -0x10, /* set default gain -15.0db*/
 	},
+	[ID_ADRF5740] = {
+		.name = "adrf5740",
+		.channels = hmc425a_channels,
+		.num_channels = ARRAY_SIZE(hmc425a_channels),
+		.num_gpios = 4,
+		.gain_min = -22000,
+		.gain_max = 0,
+		.default_gain = 0xF, /* set default gain -22.0db*/
+	},
 };
 
 static int hmc425a_probe(struct platform_device *pdev)
@@ -229,6 +249,9 @@ static int hmc425a_probe(struct platform_device *pdev)
 	indio_dev->info = &hmc425a_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
+	/* Set default gain */
+	hmc425a_write(indio_dev, st->gain);
+
 	return devm_iio_device_register(&pdev->dev, indio_dev);
 }
 
-- 
2.34.1