From: Michael Hennerich <[email protected]>
This patch adds support for the HMC425A 0.5 dB LSB GaAs MMIC 6-BIT
DIGITAL POSITIVE CONTROL ATTENUATOR, 2.2 - 8.0 GHz.
Datasheet:
https://www.analog.com/media/en/technical-documentation/data-sheets/hmc425A.pdf
Signed-off-by: Michael Hennerich <[email protected]>
Signed-off-by: Alexandru Ardelean <[email protected]>
Signed-off-by: Beniamin Bia <[email protected]>
---
drivers/iio/amplifiers/Kconfig | 10 ++
drivers/iio/amplifiers/Makefile | 1 +
drivers/iio/amplifiers/hmc425a.c | 251 +++++++++++++++++++++++++++++++
3 files changed, 262 insertions(+)
create mode 100644 drivers/iio/amplifiers/hmc425a.c
diff --git a/drivers/iio/amplifiers/Kconfig b/drivers/iio/amplifiers/Kconfig
index da7f126d197b..9b02c9a2bc8a 100644
--- a/drivers/iio/amplifiers/Kconfig
+++ b/drivers/iio/amplifiers/Kconfig
@@ -22,4 +22,14 @@ config AD8366
To compile this driver as a module, choose M here: the
module will be called ad8366.
+config HMC425
+ tristate "Analog Devices HMC425A and similar GPIO Gain Amplifiers"
+ depends on GPIOLIB
+ help
+ Say yes here to build support for Analog Devices HMC425A and similar
+ gain amplifiers or step attenuators.
+
+ To compile this driver as a module, choose M here: the
+ module will be called hmc425a.
+
endmenu
diff --git a/drivers/iio/amplifiers/Makefile b/drivers/iio/amplifiers/Makefile
index 9abef2ebe9bc..19a89db1d9b1 100644
--- a/drivers/iio/amplifiers/Makefile
+++ b/drivers/iio/amplifiers/Makefile
@@ -5,3 +5,4 @@
# When adding new entries keep the list in alphabetical order
obj-$(CONFIG_AD8366) += ad8366.o
+obj-$(CONFIG_HMC425) += hmc425a.o
\ No newline at end of file
diff --git a/drivers/iio/amplifiers/hmc425a.c b/drivers/iio/amplifiers/hmc425a.c
new file mode 100644
index 000000000000..0a412d56eb8f
--- /dev/null
+++ b/drivers/iio/amplifiers/hmc425a.c
@@ -0,0 +1,251 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * HMC425A and similar Gain Amplifiers
+ *
+ * Copyright 2020 Analog Devices Inc.
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/regulator/consumer.h>
+#include <linux/sysfs.h>
+
+enum hmc425a_type {
+ ID_HMC425A,
+};
+
+struct hmc425a_chip_info {
+ const char *name;
+ const struct iio_chan_spec *channels;
+ unsigned int num_channels;
+ unsigned int num_gpios;
+ int gain_min;
+ int gain_max;
+ int default_gain;
+};
+
+struct hmc425a_state {
+ struct regulator *reg;
+ struct mutex lock; /* protect sensor state */
+ struct hmc425a_chip_info *chip_info;
+ struct gpio_descs *gpios;
+ enum hmc425a_type type;
+ u32 gain;
+};
+
+static int hmc425a_write(struct iio_dev *indio_dev, u32 value)
+{
+ struct hmc425a_state *st = iio_priv(indio_dev);
+ int i, *values;
+
+ values = kmalloc_array(st->chip_info->num_gpios, sizeof(int),
+ GFP_KERNEL);
+ if (!values)
+ return -ENOMEM;
+
+ for (i = 0; i < st->chip_info->num_gpios; i++)
+ values[i] = (value >> i) & 1;
+
+ gpiod_set_array_value_cansleep(st->gpios->ndescs, st->gpios->desc,
+ values);
+ kfree(values);
+ return 0;
+}
+
+static int hmc425a_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val,
+ int *val2, long m)
+{
+ struct hmc425a_state *st = iio_priv(indio_dev);
+ int code, gain = 0;
+ int ret;
+
+ mutex_lock(&st->lock);
+ switch (m) {
+ case IIO_CHAN_INFO_HARDWAREGAIN:
+ code = st->gain;
+
+ switch (st->type) {
+ case ID_HMC425A:
+ gain = ~code * -500;
+ break;
+ }
+
+ *val = gain / 1000;
+ *val2 = (gain % 1000) * 1000;
+
+ ret = IIO_VAL_INT_PLUS_MICRO_DB;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ mutex_unlock(&st->lock);
+
+ return ret;
+};
+
+static int hmc425a_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int val,
+ int val2, long mask)
+{
+ struct hmc425a_state *st = iio_priv(indio_dev);
+ struct hmc425a_chip_info *inf = st->chip_info;
+ int code = 0, gain;
+ int ret;
+
+ if (val < 0)
+ gain = (val * 1000) - (val2 / 1000);
+ else
+ gain = (val * 1000) + (val2 / 1000);
+
+ if (gain > inf->gain_max || gain < inf->gain_min)
+ return -EINVAL;
+
+ switch (st->type) {
+ case ID_HMC425A:
+ code = ~((abs(gain) / 500) & 0x3F);
+ break;
+ }
+
+ mutex_lock(&st->lock);
+ switch (mask) {
+ case IIO_CHAN_INFO_HARDWAREGAIN:
+ st->gain = code;
+
+ ret = hmc425a_write(indio_dev, st->gain);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ mutex_unlock(&st->lock);
+
+ return ret;
+}
+
+static const struct iio_info hmc425a_info = {
+ .read_raw = &hmc425a_read_raw,
+ .write_raw = &hmc425a_write_raw,
+};
+
+#define HMC425A_CHAN(_channel) \
+{ \
+ .type = IIO_VOLTAGE, .output = 1, .indexed = 1, \
+ .channel = _channel, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_HARDWAREGAIN), \
+}
+
+static const struct iio_chan_spec hmc425a_channels[] = {
+ HMC425A_CHAN(0),
+};
+
+/* Match table for of_platform binding */
+static const struct of_device_id hmc425a_of_match[] = {
+ { .compatible = "adi,hmc425a", .data = (void *)ID_HMC425A },
+ {},
+};
+MODULE_DEVICE_TABLE(of, hmc425a_of_match);
+
+static void hmc425a_reg_disable(void *data)
+{
+ struct hmc425a_state *st = data;
+
+ regulator_disable(st->reg);
+}
+
+static struct hmc425a_chip_info hmc425a_chip_info_tbl[] = {
+ [ID_HMC425A] = {
+ .name = "hmc425a",
+ .channels = hmc425a_channels,
+ .num_channels = ARRAY_SIZE(hmc425a_channels),
+ .num_gpios = 6,
+ .gain_min = -31500,
+ .gain_max = 0,
+ .default_gain = -0x40, /* set default gain -31.5db*/
+ },
+};
+
+static int hmc425a_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *id;
+ struct iio_dev *indio_dev;
+ struct hmc425a_state *st;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+ id = of_match_device(hmc425a_of_match, &pdev->dev);
+ if (!id)
+ ret = -ENODEV;
+
+ st->type = (enum hmc425a_type)id->data;
+
+ st->chip_info = &hmc425a_chip_info_tbl[st->type];
+ indio_dev->num_channels = st->chip_info->num_channels;
+ indio_dev->channels = st->chip_info->channels;
+ indio_dev->name = st->chip_info->name;
+ st->gain = st->chip_info->default_gain;
+
+ st->gpios = devm_gpiod_get_array(&pdev->dev, "ctrl", GPIOD_OUT_LOW);
+ if (IS_ERR(st->gpios)) {
+ ret = PTR_ERR(st->gpios);
+ if (ret != -EPROBE_DEFER)
+ dev_err(&pdev->dev, "failed to get gpios\n");
+ return ret;
+ }
+
+ if (st->gpios->ndescs != st->chip_info->num_gpios) {
+ dev_err(&pdev->dev, "%d GPIOs needed to operate\n",
+ st->chip_info->num_gpios);
+ return -ENODEV;
+ }
+
+ st->reg = devm_regulator_get_optional(&pdev->dev, "vcc-supply");
+ if (IS_ERR(st->reg)) {
+ if (PTR_ERR(st->reg) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
+ st->reg = NULL;
+ } else {
+ ret = regulator_enable(st->reg);
+ if (ret)
+ return ret;
+ ret = devm_add_action_or_reset(&pdev->dev, hmc425a_reg_disable,
+ st);
+ if (ret)
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, indio_dev);
+ mutex_init(&st->lock);
+
+ indio_dev->dev.parent = &pdev->dev;
+ indio_dev->info = &hmc425a_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ return devm_iio_device_register(&pdev->dev, indio_dev);
+}
+
+static struct platform_driver hmc425a_driver = {
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = hmc425a_of_match,
+ },
+ .probe = hmc425a_probe,
+};
+module_platform_driver(hmc425a_driver);
+
+MODULE_AUTHOR("Michael Hennerich <[email protected]>");
+MODULE_DESCRIPTION("Analog Devices HMC425A and similar GPIO control Gain Amplifiers");
+MODULE_LICENSE("GPL v2");
--
2.17.1
From: Michael Hennerich <[email protected]>
Document support for Analog Devices MC425A Step Attenuator.
Signed-off-by: Michael Hennerich <[email protected]>
Signed-off-by: Beniamin Bia <[email protected]>
---
.../bindings/iio/amplifiers/adi,hmc425a.yaml | 56 +++++++++++++++++++
1 file changed, 56 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/amplifiers/adi,hmc425a.yaml
diff --git a/Documentation/devicetree/bindings/iio/amplifiers/adi,hmc425a.yaml b/Documentation/devicetree/bindings/iio/amplifiers/adi,hmc425a.yaml
new file mode 100644
index 000000000000..a0afa661f4ac
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/amplifiers/adi,hmc425a.yaml
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/amplifiers/adi,hmc425a.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: HMC425A 6-bit Digital Step Attenuator
+
+maintainers:
+- Michael Hennerich <[email protected]>
+- Beniamin Bia <[email protected]>
+
+description: |
+ Digital Step Attenuator IIO device with gpio interface.
+ HMC425A 0.5 dB LSB GaAs MMIC 6-BIT DIGITAL POSITIVE CONTROL ATTENUATOR, 2.2 - 8.0 GHz
+ https://www.analog.com/media/en/technical-documentation/data-sheets/hmc425A.pdf
+
+properties:
+ compatible:
+ enum:
+ - adi,hmc425a
+
+ vcc-supply:
+ description:
+ Digital voltage regulator (see regulator/regulator.txt)
+ maxItems: 1
+
+ ctrl-gpios:
+ description:
+ Must contain an array of 6 GPIO specifiers, referring to the GPIO pins
+ connected to the control pins V1-V6.
+ maxItems: 6
+
+required:
+ - compatible
+ - ctrl-gpios
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ gpio {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ gpio_hmc425a: hmc425a {
+ compatible = "adi,hmc425a";
+ ctrl-gpios = <&gpio 40 GPIO_ACTIVE_HIGH>,
+ <&gpio 39 GPIO_ACTIVE_HIGH>,
+ <&gpio 38 GPIO_ACTIVE_HIGH>,
+ <&gpio 37 GPIO_ACTIVE_HIGH>,
+ <&gpio 36 GPIO_ACTIVE_HIGH>,
+ <&gpio 35 GPIO_ACTIVE_HIGH>;
+
+ vcc-supply = <&foo>;
+ };
+ };
+...
--
2.17.1
Add Beniamin Bia and Michael Hennerich as maintainers for HMC425A
attenuator.
Signed-off-by: Beniamin Bia <[email protected]>
---
MAINTAINERS | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index ec05a06d7ddb..9ae436d67edf 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1057,6 +1057,15 @@ F: drivers/iio/adc/ltc249*
X: drivers/iio/*/adjd*
F: drivers/staging/iio/*/ad*
+ANALOG DEVICES INC HMC425A DRIVER
+M: Beniamin Bia <[email protected]>
+M: Michael Hennerich <[email protected]>
+L: [email protected]
+W: http://ez.analog.com/community/linux-device-drivers
+S: Supported
+F: drivers/iio/amplifiers/hmc425a.c
+F: Documentation/devicetree/bindings/iio/amplifiers/adi,hmc425a.yaml
+
ANALOGBITS PLL LIBRARIES
M: Paul Walmsley <[email protected]>
S: Supported
--
2.17.1
On Wed, Jan 22, 2020 at 02:17:01PM +0200, Beniamin Bia wrote:
> From: Michael Hennerich <[email protected]>
>
> Document support for Analog Devices MC425A Step Attenuator.
>
> Signed-off-by: Michael Hennerich <[email protected]>
> Signed-off-by: Beniamin Bia <[email protected]>
> ---
> .../bindings/iio/amplifiers/adi,hmc425a.yaml | 56 +++++++++++++++++++
> 1 file changed, 56 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/amplifiers/adi,hmc425a.yaml
>
> diff --git a/Documentation/devicetree/bindings/iio/amplifiers/adi,hmc425a.yaml b/Documentation/devicetree/bindings/iio/amplifiers/adi,hmc425a.yaml
> new file mode 100644
> index 000000000000..a0afa661f4ac
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/amplifiers/adi,hmc425a.yaml
> @@ -0,0 +1,56 @@
> +# SPDX-License-Identifier: GPL-2.0
Dual license new bindings:
(GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/amplifiers/adi,hmc425a.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: HMC425A 6-bit Digital Step Attenuator
> +
> +maintainers:
> +- Michael Hennerich <[email protected]>
> +- Beniamin Bia <[email protected]>
> +
> +description: |
> + Digital Step Attenuator IIO device with gpio interface.
> + HMC425A 0.5 dB LSB GaAs MMIC 6-BIT DIGITAL POSITIVE CONTROL ATTENUATOR, 2.2 - 8.0 GHz
> + https://www.analog.com/media/en/technical-documentation/data-sheets/hmc425A.pdf
> +
> +properties:
> + compatible:
> + enum:
> + - adi,hmc425a
> +
> + vcc-supply:
> + description:
> + Digital voltage regulator (see regulator/regulator.txt)
> + maxItems: 1
All supplies are a single entry, so drop this. Really,
'vcc-supply: true' is sufficient.
> +
> + ctrl-gpios:
> + description:
> + Must contain an array of 6 GPIO specifiers, referring to the GPIO pins
> + connected to the control pins V1-V6.
> + maxItems: 6
> +
> +required:
> + - compatible
> + - ctrl-gpios
> +
> +examples:
> + - |
> + #include <dt-bindings/gpio/gpio.h>
> + gpio {
> + #address-cells = <1>;
> + #size-cells = <0>;
GPIO clients are not child nodes of GPIO controllers, so you can remove
this node.
> + gpio_hmc425a: hmc425a {
> + compatible = "adi,hmc425a";
> + ctrl-gpios = <&gpio 40 GPIO_ACTIVE_HIGH>,
> + <&gpio 39 GPIO_ACTIVE_HIGH>,
> + <&gpio 38 GPIO_ACTIVE_HIGH>,
> + <&gpio 37 GPIO_ACTIVE_HIGH>,
> + <&gpio 36 GPIO_ACTIVE_HIGH>,
> + <&gpio 35 GPIO_ACTIVE_HIGH>;
> +
> + vcc-supply = <&foo>;
> + };
> + };
> +...
> --
> 2.17.1
>