iio: amplifiers: ad8366: add support for HMC792A Attenuator

This change adds support for the HMC792A Digital Attenuator. The
HMC792A is a broadband 6-bit GaAs MMIC Digital Attenuator operating
from DC to 6.0 GHz with 15.75 dB attenuation control range in 0.25 dB steps.

Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/hmc792a.pdf
Signed-off-by: Kim Seer Paller <kimseer.paller@analog.com>
Link: https://lore.kernel.org/r/20230721121038.183404-1-kimseer.paller@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/amplifiers/Kconfig b/drivers/iio/amplifiers/Kconfig
index f217a2a1e9586c15d7c7528f5e7e9b1f38470507..b54fe01734b0d7e91198bcc22e5cf764dfe537a4 100644 (file)
--- a/drivers/iio/amplifiers/Kconfig
+++ b/drivers/iio/amplifiers/Kconfig
@@ -18,6 +18,7 @@ config AD8366
            AD8366 Dual-Digital Variable Gain Amplifier (VGA)
            ADA4961 BiCMOS RF Digital Gain Amplifier (DGA)
            ADL5240 Digitally controlled variable gain amplifier (VGA)
+           HMC792A 0.25 dB LSB GaAs MMIC 6-Bit Digital Attenuator
            HMC1119 0.25 dB LSB, 7-Bit, Silicon Digital Attenuator
 
          To compile this driver as a module, choose M here: the

diff --git a/drivers/iio/amplifiers/ad8366.c b/drivers/iio/amplifiers/ad8366.c
index 8d8c8ea94258fa0e543947e9b86a29e529b948ce..31564afb13a2028f018926663387b47bfc967199 100644 (file)
--- a/drivers/iio/amplifiers/ad8366.c
+++ b/drivers/iio/amplifiers/ad8366.c
@@ -5,6 +5,7 @@
  *   AD8366 Dual-Digital Variable Gain Amplifier (VGA)
  *   ADA4961 BiCMOS RF Digital Gain Amplifier (DGA)
  *   ADL5240 Digitally controlled variable gain amplifier (VGA)
+ *   HMC792A 0.25 dB LSB GaAs MMIC 6-Bit Digital Attenuator
  *   HMC1119 0.25 dB LSB, 7-Bit, Silicon Digital Attenuator
  *
  * Copyright 2012-2019 Analog Devices Inc.
@@ -28,6 +29,7 @@ enum ad8366_type {
        ID_AD8366,
        ID_ADA4961,
        ID_ADL5240,
+       ID_HMC792,
        ID_HMC1119,
 };
 
@@ -64,6 +66,10 @@ static struct ad8366_info ad8366_infos[] = {
                .gain_min = -11500,
                .gain_max = 20000,
        },
+       [ID_HMC792] = {
+               .gain_min = -15750,
+               .gain_max = 0,
+       },
        [ID_HMC1119] = {
                .gain_min = -31750,
                .gain_max = 0,
@@ -90,6 +96,7 @@ static int ad8366_write(struct iio_dev *indio_dev,
        case ID_ADL5240:
                st->data[0] = (ch_a & 0x3F);
                break;
+       case ID_HMC792:
        case ID_HMC1119:
                st->data[0] = ch_a;
                break;
@@ -127,6 +134,9 @@ static int ad8366_read_raw(struct iio_dev *indio_dev,
                case ID_ADL5240:
                        gain = 20000 - 31500 + code * 500;
                        break;
+               case ID_HMC792:
+                       gain = -1 * code * 500;
+                       break;
                case ID_HMC1119:
                        gain = -1 * code * 250;
                        break;
@@ -176,6 +186,9 @@ static int ad8366_write_raw(struct iio_dev *indio_dev,
        case ID_ADL5240:
                code = ((gain - 500 - 20000) / 500) & 0x3F;
                break;
+       case ID_HMC792:
+               code = (abs(gain) / 500) & 0x3F;
+               break;
        case ID_HMC1119:
                code = (abs(gain) / 250) & 0x7F;
                break;
@@ -261,6 +274,7 @@ static int ad8366_probe(struct spi_device *spi)
                break;
        case ID_ADA4961:
        case ID_ADL5240:
+       case ID_HMC792:
        case ID_HMC1119:
                st->reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset", GPIOD_OUT_HIGH);
                if (IS_ERR(st->reset_gpio)) {
@@ -314,6 +328,7 @@ static const struct spi_device_id ad8366_id[] = {
        {"ad8366",  ID_AD8366},
        {"ada4961", ID_ADA4961},
        {"adl5240", ID_ADL5240},
+       {"hmc792a", ID_HMC792},
        {"hmc1119", ID_HMC1119},
        {}
 };