[PATCH v8 0/2] iio: proximity: driver for vcnl3020

[PATCH v8 0/2] iio: proximity: driver for vcnl3020

[Ivan Mikhaylov]

Add proximity sensor driver for Vishay vcnl3020. Only on-demand
measurement is supported for now.

Changes from v7:
   1. forgot to add Reviewed-by tag.

Changes from v6:
   1. minor changes
     1.1 remove VCNL_DRV_NAME
     1.2 add braces in get_and_apply_property

Changes from v5:
   1. add get_and_apply_property function for optional parameters.
   2. minor changes.

Changes from v4:
   1. add vdd-supply,vddio-supply,interrupts properties into yaml.
   2. led-current -> vishay,led-current-milliamp in yaml.
   3. add possible values enum list.
   4. add bulk_read for result hi/lo registers.
   5. add description of vcnl3020_data structure.
   6. vcnl3020 id table is removed.
   7. make "vishay,led-current-milliamp" optional in yaml and code.

Changes from v3:
   1. minor changes.
   2. add i2c block to fix dts section in yaml.

Changes from v2:
   1. using regmap_read_poll_timeout instead of do-while in measurement
      function.
   2. change struct i2client* in vcnl3020_data to struct dev*
   3. enable REGMAP_I2C in Kconfig

Changes from v1:
   1. using regmap interface instead of i2c_smbus_* calls.
   2. switch from probe to probe_new.
   3. s32/int32_t -> int

Ivan Mikhaylov (2):
  iio: proximity: provide device tree binding document
  iio: proximity: Add driver support for vcnl3020 proximity sensor

 .../bindings/iio/proximity/vcnl3020.yaml      |  65 +++++
 drivers/iio/proximity/Kconfig                 |  11 +
 drivers/iio/proximity/Makefile                |   1 +
 drivers/iio/proximity/vcnl3020.c              | 234 ++++++++++++++++++
 4 files changed, 311 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml
 create mode 100644 drivers/iio/proximity/vcnl3020.c

-- 
2.21.1

[PATCH v8 1/2] iio: proximity: provide device tree binding document

[Ivan Mikhaylov]

Mostly standard i2c driver with some additional led-current option
for vcnl3020.

Signed-off-by: Ivan Mikhaylov <i.mikhaylov@yadro.com>
---
 .../bindings/iio/proximity/vcnl3020.yaml      | 65 +++++++++++++++++++
 1 file changed, 65 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml

diff --git a/Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml b/Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml
new file mode 100644
index 000000000000..29ab2dee1694
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml
@@ -0,0 +1,65 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/proximity/vcnl3020.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Integrated Proximity Sensor With Infrared Emitter
+
+maintainers:
+  - Ivan Mikhaylov <i.mikhaylov@yadro.com>
+
+description: |
+  The VCNL3020 is a fully integrated proximity sensor. Fully integrated means
+  that the infrared emitter is included in the package. It has 16-bit
+  resolution. It includes a signal processing IC and features standard I2C
+  communication interface. It features an interrupt function.
+
+  Specifications about the devices can be found at:
+  https://www.vishay.com/docs/84150/vcnl3020.pdf
+
+properties:
+  compatible:
+    enum:
+      - vishay,vcnl3020
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    description: IRQ line for the proximity sensor
+    maxItems: 1
+
+  vdd-supply:
+    description: Regulator that provides power to the sensor
+
+  vddio-supply:
+    description: Regulator that provides power to the bus
+
+  vishay,led-current-milliamp:
+    description:
+        IR LED current value with valid Range = 0 to 20d. e.g. 0 = 0 mA,
+        1 = 10 mA, 20 = 200 mA (2 = 20 mA = DEFAULT). LED Current is
+        limited to 200 mA for values higher than decimal 20.
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint32
+      - enum: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
+              18, 19, 20]
+
+required:
+  - compatible
+  - reg
+
+examples:
+  - |
+    i2c {
+
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        proximity@13 {
+              compatible = "vishay,vcnl3020";
+              reg = <0x13>;
+              vishay,led-current-milliamp = <0x14>;
+        };
+    };
-- 
2.21.1

[PATCH v8 2/2] iio: proximity: Add driver support for vcnl3020 proximity sensor

[Ivan Mikhaylov]

Proximity sensor driver based on light/vcnl4000.c code.
For now supports only the single on-demand measurement.

The VCNL3020 is a fully integrated proximity sensor. Fully
integrated means that the infrared emitter is included in the
package. It has 16-bit resolution. It includes a signal
processing IC and features standard I2C communication
interface. It features an interrupt function.

Datasheet: http://www.vishay.com/docs/84150/vcnl3020.pdf
Signed-off-by: Ivan Mikhaylov <i.mikhaylov@yadro.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
---
 drivers/iio/proximity/Kconfig    |  11 ++
 drivers/iio/proximity/Makefile   |   1 +
 drivers/iio/proximity/vcnl3020.c | 234 +++++++++++++++++++++++++++++++
 3 files changed, 246 insertions(+)
 create mode 100644 drivers/iio/proximity/vcnl3020.c

diff --git a/drivers/iio/proximity/Kconfig b/drivers/iio/proximity/Kconfig
index d53601447da4..b8d2b17e60ac 100644
--- a/drivers/iio/proximity/Kconfig
+++ b/drivers/iio/proximity/Kconfig
@@ -112,6 +112,17 @@ config SRF08
 	  To compile this driver as a module, choose M here: the
 	  module will be called srf08.
 
+config VCNL3020
+	tristate "VCNL3020 proximity sensor"
+	select REGMAP_I2C
+	depends on I2C
+	help
+	  Say Y here if you want to build a driver for the Vishay VCNL3020
+	  proximity sensor.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called vcnl3020.
+
 config VL53L0X_I2C
 	tristate "STMicroelectronics VL53L0X ToF ranger sensor (I2C)"
 	depends on I2C
diff --git a/drivers/iio/proximity/Makefile b/drivers/iio/proximity/Makefile
index 0bb5f9de13d6..8245978ced30 100644
--- a/drivers/iio/proximity/Makefile
+++ b/drivers/iio/proximity/Makefile
@@ -12,5 +12,6 @@ obj-$(CONFIG_RFD77402)		+= rfd77402.o
 obj-$(CONFIG_SRF04)		+= srf04.o
 obj-$(CONFIG_SRF08)		+= srf08.o
 obj-$(CONFIG_SX9500)		+= sx9500.o
+obj-$(CONFIG_VCNL3020)		+= vcnl3020.o
 obj-$(CONFIG_VL53L0X_I2C)	+= vl53l0x-i2c.o
 
diff --git a/drivers/iio/proximity/vcnl3020.c b/drivers/iio/proximity/vcnl3020.c
new file mode 100644
index 000000000000..43282309a360
--- /dev/null
+++ b/drivers/iio/proximity/vcnl3020.c
@@ -0,0 +1,234 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Support for Vishay VCNL3020 proximity sensor on i2c bus.
+ * Based on Vishay VCNL4000 driver code.
+ *
+ * TODO: interrupts.
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/regmap.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define VCNL3020_PROD_ID	0x21
+
+#define VCNL_COMMAND		0x80 /* Command register */
+#define VCNL_PROD_REV		0x81 /* Product ID and Revision ID */
+#define VCNL_PROXIMITY_RATE	0x82 /* Rate of Proximity Measurement */
+#define VCNL_LED_CURRENT	0x83 /* IR LED current for proximity mode */
+#define VCNL_PS_RESULT_HI	0x87 /* Proximity result register, MSB */
+#define VCNL_PS_RESULT_LO	0x88 /* Proximity result register, LSB */
+#define VCNL_PS_ICR		0x89 /* Interrupt Control Register  */
+
+#define VCNL_PS_LO_THR_HI	0x8a /* High byte of low threshold value */
+#define VCNL_PS_LO_THR_LO	0x8b /* Low byte of low threshold value */
+#define VCNL_PS_HI_THR_HI	0x8c /* High byte of high threshold value */
+#define VCNL_PS_HI_THR_LO	0x8d /* Low byte of high threshold value */
+#define VCNL_ISR		0x8e /* Interrupt Status Register */
+#define VCNL_PS_MOD_ADJ		0x8f /* Proximity Modulator Timing Adjustment */
+
+/* Bit masks for COMMAND register */
+#define VCNL_PS_RDY		BIT(5) /* proximity data ready? */
+#define VCNL_PS_OD		BIT(3) /* start on-demand proximity
+					* measurement
+					*/
+
+#define VCNL_ON_DEMAND_TIMEOUT_US	100000
+#define VCNL_POLL_US			20000
+
+/**
+ * struct vcnl3020_data - vcnl3020 specific data.
+ * @regmap:	device register map.
+ * @dev:	vcnl3020 device.
+ * @rev:	revision id.
+ * @lock:	lock for protecting access to device hardware registers.
+ */
+struct vcnl3020_data {
+	struct regmap *regmap;
+	struct device *dev;
+	u8 rev;
+	struct mutex lock;
+};
+
+static int get_and_apply_property(struct vcnl3020_data *data, const char *prop,
+				  u32 reg)
+{
+	int rc;
+	u32 val;
+
+	rc = device_property_read_u32(data->dev, prop, &val);
+	if (rc)
+		return 0;
+
+	rc = regmap_write(data->regmap, reg, val);
+	if (rc) {
+		dev_err(data->dev, "Error (%d) setting property (%s)",
+			rc, prop);
+	}
+
+	return rc;
+}
+
+static int vcnl3020_init(struct vcnl3020_data *data)
+{
+	int rc;
+	unsigned int reg;
+
+	rc = regmap_read(data->regmap, VCNL_PROD_REV, &reg);
+	if (rc) {
+		dev_err(data->dev,
+			"Error (%d) reading product revision", rc);
+		return rc;
+	}
+
+	if (reg != VCNL3020_PROD_ID) {
+		dev_err(data->dev,
+			"Product id (%x) did not match vcnl3020 (%x)", reg,
+			VCNL3020_PROD_ID);
+		return -ENODEV;
+	}
+
+	data->rev = reg;
+	mutex_init(&data->lock);
+
+	return get_and_apply_property(data, "vishay,led-current-milliamp",
+				     VCNL_LED_CURRENT);
+};
+
+static int vcnl3020_measure_proximity(struct vcnl3020_data *data, int *val)
+{
+	int rc;
+	unsigned int reg;
+	__be16 res;
+
+	mutex_lock(&data->lock);
+
+	rc = regmap_write(data->regmap, VCNL_COMMAND, VCNL_PS_OD);
+	if (rc)
+		goto err_unlock;
+
+	/* wait for data to become ready */
+	rc = regmap_read_poll_timeout(data->regmap, VCNL_COMMAND, reg,
+				      reg & VCNL_PS_RDY, VCNL_POLL_US,
+				      VCNL_ON_DEMAND_TIMEOUT_US);
+	if (rc) {
+		dev_err(data->dev,
+			"Error (%d) reading vcnl3020 command register", rc);
+		goto err_unlock;
+	}
+
+	/* high & low result bytes read */
+	rc = regmap_bulk_read(data->regmap, VCNL_PS_RESULT_HI, &res,
+			      sizeof(res));
+	if (rc)
+		goto err_unlock;
+
+	*val = be16_to_cpu(res);
+
+err_unlock:
+	mutex_unlock(&data->lock);
+
+	return rc;
+}
+
+static const struct iio_chan_spec vcnl3020_channels[] = {
+	{
+		.type = IIO_PROXIMITY,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+	},
+};
+
+static int vcnl3020_read_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan, int *val,
+			     int *val2, long mask)
+{
+	int rc;
+	struct vcnl3020_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		switch (chan->type) {
+		case IIO_PROXIMITY:
+			rc = vcnl3020_measure_proximity(data, val);
+			if (rc)
+				return rc;
+			return IIO_VAL_INT;
+		default:
+			return -EINVAL;
+		}
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_info vcnl3020_info = {
+	.read_raw = vcnl3020_read_raw,
+};
+
+static const struct regmap_config vcnl3020_regmap_config = {
+	.reg_bits	= 8,
+	.val_bits	= 8,
+	.max_register	= VCNL_PS_MOD_ADJ,
+};
+
+static int vcnl3020_probe(struct i2c_client *client)
+{
+	struct vcnl3020_data *data;
+	struct iio_dev *indio_dev;
+	struct regmap *regmap;
+	int rc;
+
+	regmap = devm_regmap_init_i2c(client, &vcnl3020_regmap_config);
+	if (IS_ERR(regmap)) {
+		dev_err(&client->dev, "regmap_init failed!");
+		return PTR_ERR(regmap);
+	}
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	data->regmap = regmap;
+	data->dev = &client->dev;
+
+	rc = vcnl3020_init(data);
+	if (rc)
+		return rc;
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &vcnl3020_info;
+	indio_dev->channels = vcnl3020_channels;
+	indio_dev->num_channels = ARRAY_SIZE(vcnl3020_channels);
+	indio_dev->name = "vcnl3020";
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+static const struct of_device_id vcnl3020_of_match[] = {
+	{
+		.compatible = "vishay,vcnl3020",
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, vcnl3020_of_match);
+
+static struct i2c_driver vcnl3020_driver = {
+	.driver = {
+		.name   = "vcnl3020",
+		.of_match_table = vcnl3020_of_match,
+	},
+	.probe_new  = vcnl3020_probe,
+};
+module_i2c_driver(vcnl3020_driver);
+
+MODULE_AUTHOR("Ivan Mikhaylov <i.mikhaylov@yadro.com>");
+MODULE_DESCRIPTION("Vishay VCNL3020 proximity sensor driver");
+MODULE_LICENSE("GPL");
-- 
2.21.1

Re: [PATCH v8 0/2] iio: proximity: driver for vcnl3020

[Andy Shevchenko]

On Mon, Apr 6, 2020 at 8:19 PM Ivan Mikhaylov <i.mikhaylov@yadro.com> wrote:
>
> Add proximity sensor driver for Vishay vcnl3020. Only on-demand
> measurement is supported for now.
>

Thank you!

> Changes from v7:
>    1. forgot to add Reviewed-by tag.
>
> Changes from v6:
>    1. minor changes
>      1.1 remove VCNL_DRV_NAME
>      1.2 add braces in get_and_apply_property
>
> Changes from v5:
>    1. add get_and_apply_property function for optional parameters.
>    2. minor changes.
>
> Changes from v4:
>    1. add vdd-supply,vddio-supply,interrupts properties into yaml.
>    2. led-current -> vishay,led-current-milliamp in yaml.
>    3. add possible values enum list.
>    4. add bulk_read for result hi/lo registers.
>    5. add description of vcnl3020_data structure.
>    6. vcnl3020 id table is removed.
>    7. make "vishay,led-current-milliamp" optional in yaml and code.
>
> Changes from v3:
>    1. minor changes.
>    2. add i2c block to fix dts section in yaml.
>
> Changes from v2:
>    1. using regmap_read_poll_timeout instead of do-while in measurement
>       function.
>    2. change struct i2client* in vcnl3020_data to struct dev*
>    3. enable REGMAP_I2C in Kconfig
>
> Changes from v1:
>    1. using regmap interface instead of i2c_smbus_* calls.
>    2. switch from probe to probe_new.
>    3. s32/int32_t -> int
>
> Ivan Mikhaylov (2):
>   iio: proximity: provide device tree binding document
>   iio: proximity: Add driver support for vcnl3020 proximity sensor
>
>  .../bindings/iio/proximity/vcnl3020.yaml      |  65 +++++
>  drivers/iio/proximity/Kconfig                 |  11 +
>  drivers/iio/proximity/Makefile                |   1 +
>  drivers/iio/proximity/vcnl3020.c              | 234 ++++++++++++++++++
>  4 files changed, 311 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml
>  create mode 100644 drivers/iio/proximity/vcnl3020.c
>
> --
> 2.21.1
>


-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v8 1/2] iio: proximity: provide device tree binding document

[Jonathan Cameron]

On Mon, 6 Apr 2020 20:20:01 +0300
Ivan Mikhaylov <i.mikhaylov@yadro.com> wrote:

> Mostly standard i2c driver with some additional led-current option
> for vcnl3020.
> 
> Signed-off-by: Ivan Mikhaylov <i.mikhaylov@yadro.com>
One comment inline preempting likely review from Rob.  I'd also like
there to be plenty of time for Rob and others to take a look before I
apply this.

Thanks,

Jonathan

> ---
>  .../bindings/iio/proximity/vcnl3020.yaml      | 65 +++++++++++++++++++
>  1 file changed, 65 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml
> 
> diff --git a/Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml b/Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml
> new file mode 100644
> index 000000000000..29ab2dee1694
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml
> @@ -0,0 +1,65 @@
> +# SPDX-License-Identifier: GPL-2.0

Very much preferred for new bindings to have a dual license including
BSD to allow there use outside of the Linux kernel.

> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/proximity/vcnl3020.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Integrated Proximity Sensor With Infrared Emitter
> +
> +maintainers:
> +  - Ivan Mikhaylov <i.mikhaylov@yadro.com>
> +
> +description: |
> +  The VCNL3020 is a fully integrated proximity sensor. Fully integrated means
> +  that the infrared emitter is included in the package. It has 16-bit
> +  resolution. It includes a signal processing IC and features standard I2C
> +  communication interface. It features an interrupt function.
> +
> +  Specifications about the devices can be found at:
> +  https://www.vishay.com/docs/84150/vcnl3020.pdf
> +
> +properties:
> +  compatible:
> +    enum:
> +      - vishay,vcnl3020
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    description: IRQ line for the proximity sensor
> +    maxItems: 1
> +
> +  vdd-supply:
> +    description: Regulator that provides power to the sensor
> +
> +  vddio-supply:
> +    description: Regulator that provides power to the bus
> +
> +  vishay,led-current-milliamp:
> +    description:
> +        IR LED current value with valid Range = 0 to 20d. e.g. 0 = 0 mA,
> +        1 = 10 mA, 20 = 200 mA (2 = 20 mA = DEFAULT). LED Current is
> +        limited to 200 mA for values higher than decimal 20.
> +    allOf:
> +      - $ref: /schemas/types.yaml#/definitions/uint32
> +      - enum: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
> +              18, 19, 20]
> +
> +required:
> +  - compatible
> +  - reg
> +
> +examples:
> +  - |
> +    i2c {
> +
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        proximity@13 {
> +              compatible = "vishay,vcnl3020";
> +              reg = <0x13>;
> +              vishay,led-current-milliamp = <0x14>;
> +        };
> +    };

Re: [PATCH v8 2/2] iio: proximity: Add driver support for vcnl3020 proximity sensor

[Jonathan Cameron]

On Mon, 6 Apr 2020 20:20:02 +0300
Ivan Mikhaylov <i.mikhaylov@yadro.com> wrote:

> Proximity sensor driver based on light/vcnl4000.c code.
> For now supports only the single on-demand measurement.
> 
> The VCNL3020 is a fully integrated proximity sensor. Fully
> integrated means that the infrared emitter is included in the
> package. It has 16-bit resolution. It includes a signal
> processing IC and features standard I2C communication
> interface. It features an interrupt function.
> 
> Datasheet: http://www.vishay.com/docs/84150/vcnl3020.pdf
> Signed-off-by: Ivan Mikhaylov <i.mikhaylov@yadro.com>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

One trivial comment inline that I can fixup whilst applying.  However
if you are respining for any reason feel free to tidy it up!

Thanks,

Jonathan

> ---
>  drivers/iio/proximity/Kconfig    |  11 ++
>  drivers/iio/proximity/Makefile   |   1 +
>  drivers/iio/proximity/vcnl3020.c | 234 +++++++++++++++++++++++++++++++
>  3 files changed, 246 insertions(+)
>  create mode 100644 drivers/iio/proximity/vcnl3020.c
> 
> diff --git a/drivers/iio/proximity/Kconfig b/drivers/iio/proximity/Kconfig
> index d53601447da4..b8d2b17e60ac 100644
> --- a/drivers/iio/proximity/Kconfig
> +++ b/drivers/iio/proximity/Kconfig
> @@ -112,6 +112,17 @@ config SRF08
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called srf08.
>  
> +config VCNL3020
> +	tristate "VCNL3020 proximity sensor"
> +	select REGMAP_I2C
> +	depends on I2C
> +	help
> +	  Say Y here if you want to build a driver for the Vishay VCNL3020
> +	  proximity sensor.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called vcnl3020.
> +
>  config VL53L0X_I2C
>  	tristate "STMicroelectronics VL53L0X ToF ranger sensor (I2C)"
>  	depends on I2C
> diff --git a/drivers/iio/proximity/Makefile b/drivers/iio/proximity/Makefile
> index 0bb5f9de13d6..8245978ced30 100644
> --- a/drivers/iio/proximity/Makefile
> +++ b/drivers/iio/proximity/Makefile
> @@ -12,5 +12,6 @@ obj-$(CONFIG_RFD77402)		+= rfd77402.o
>  obj-$(CONFIG_SRF04)		+= srf04.o
>  obj-$(CONFIG_SRF08)		+= srf08.o
>  obj-$(CONFIG_SX9500)		+= sx9500.o
> +obj-$(CONFIG_VCNL3020)		+= vcnl3020.o
>  obj-$(CONFIG_VL53L0X_I2C)	+= vl53l0x-i2c.o
>  
> diff --git a/drivers/iio/proximity/vcnl3020.c b/drivers/iio/proximity/vcnl3020.c
> new file mode 100644
> index 000000000000..43282309a360
> --- /dev/null
> +++ b/drivers/iio/proximity/vcnl3020.c
> @@ -0,0 +1,234 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Support for Vishay VCNL3020 proximity sensor on i2c bus.
> + * Based on Vishay VCNL4000 driver code.
> + *
> + * TODO: interrupts.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/i2c.h>
> +#include <linux/err.h>
> +#include <linux/delay.h>
> +#include <linux/regmap.h>
> +
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +
> +#define VCNL3020_PROD_ID	0x21
> +
> +#define VCNL_COMMAND		0x80 /* Command register */
> +#define VCNL_PROD_REV		0x81 /* Product ID and Revision ID */
> +#define VCNL_PROXIMITY_RATE	0x82 /* Rate of Proximity Measurement */
> +#define VCNL_LED_CURRENT	0x83 /* IR LED current for proximity mode */
> +#define VCNL_PS_RESULT_HI	0x87 /* Proximity result register, MSB */
> +#define VCNL_PS_RESULT_LO	0x88 /* Proximity result register, LSB */
> +#define VCNL_PS_ICR		0x89 /* Interrupt Control Register  */
> +
> +#define VCNL_PS_LO_THR_HI	0x8a /* High byte of low threshold value */
> +#define VCNL_PS_LO_THR_LO	0x8b /* Low byte of low threshold value */
> +#define VCNL_PS_HI_THR_HI	0x8c /* High byte of high threshold value */
> +#define VCNL_PS_HI_THR_LO	0x8d /* Low byte of high threshold value */
> +#define VCNL_ISR		0x8e /* Interrupt Status Register */
> +#define VCNL_PS_MOD_ADJ		0x8f /* Proximity Modulator Timing Adjustment */
> +
> +/* Bit masks for COMMAND register */
> +#define VCNL_PS_RDY		BIT(5) /* proximity data ready? */
> +#define VCNL_PS_OD		BIT(3) /* start on-demand proximity
> +					* measurement
> +					*/
> +
> +#define VCNL_ON_DEMAND_TIMEOUT_US	100000
> +#define VCNL_POLL_US			20000
> +
> +/**
> + * struct vcnl3020_data - vcnl3020 specific data.
> + * @regmap:	device register map.
> + * @dev:	vcnl3020 device.
> + * @rev:	revision id.
> + * @lock:	lock for protecting access to device hardware registers.
> + */
> +struct vcnl3020_data {
> +	struct regmap *regmap;
> +	struct device *dev;
> +	u8 rev;
> +	struct mutex lock;
> +};
> +
> +static int get_and_apply_property(struct vcnl3020_data *data, const char *prop,
> +				  u32 reg)

Ideally this would have a prefix. I may fix up whilst applying.

> +{
> +	int rc;
> +	u32 val;
> +
> +	rc = device_property_read_u32(data->dev, prop, &val);
> +	if (rc)
> +		return 0;
> +
> +	rc = regmap_write(data->regmap, reg, val);
> +	if (rc) {
> +		dev_err(data->dev, "Error (%d) setting property (%s)",
> +			rc, prop);
> +	}
> +
> +	return rc;
> +}
> +
> +static int vcnl3020_init(struct vcnl3020_data *data)
> +{
> +	int rc;
> +	unsigned int reg;
> +
> +	rc = regmap_read(data->regmap, VCNL_PROD_REV, &reg);
> +	if (rc) {
> +		dev_err(data->dev,
> +			"Error (%d) reading product revision", rc);
> +		return rc;
> +	}
> +
> +	if (reg != VCNL3020_PROD_ID) {
> +		dev_err(data->dev,
> +			"Product id (%x) did not match vcnl3020 (%x)", reg,
> +			VCNL3020_PROD_ID);
> +		return -ENODEV;
> +	}
> +
> +	data->rev = reg;
> +	mutex_init(&data->lock);
> +
> +	return get_and_apply_property(data, "vishay,led-current-milliamp",
> +				     VCNL_LED_CURRENT);
> +};
> +
> +static int vcnl3020_measure_proximity(struct vcnl3020_data *data, int *val)
> +{
> +	int rc;
> +	unsigned int reg;
> +	__be16 res;
> +
> +	mutex_lock(&data->lock);
> +
> +	rc = regmap_write(data->regmap, VCNL_COMMAND, VCNL_PS_OD);
> +	if (rc)
> +		goto err_unlock;
> +
> +	/* wait for data to become ready */
> +	rc = regmap_read_poll_timeout(data->regmap, VCNL_COMMAND, reg,
> +				      reg & VCNL_PS_RDY, VCNL_POLL_US,
> +				      VCNL_ON_DEMAND_TIMEOUT_US);
> +	if (rc) {
> +		dev_err(data->dev,
> +			"Error (%d) reading vcnl3020 command register", rc);
> +		goto err_unlock;
> +	}
> +
> +	/* high & low result bytes read */
> +	rc = regmap_bulk_read(data->regmap, VCNL_PS_RESULT_HI, &res,
> +			      sizeof(res));
> +	if (rc)
> +		goto err_unlock;
> +
> +	*val = be16_to_cpu(res);
> +
> +err_unlock:
> +	mutex_unlock(&data->lock);
> +
> +	return rc;
> +}
> +
> +static const struct iio_chan_spec vcnl3020_channels[] = {
> +	{
> +		.type = IIO_PROXIMITY,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> +	},
> +};
> +
> +static int vcnl3020_read_raw(struct iio_dev *indio_dev,
> +			     struct iio_chan_spec const *chan, int *val,
> +			     int *val2, long mask)
> +{
> +	int rc;
> +	struct vcnl3020_data *data = iio_priv(indio_dev);
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		switch (chan->type) {
> +		case IIO_PROXIMITY:
> +			rc = vcnl3020_measure_proximity(data, val);
> +			if (rc)
> +				return rc;
> +			return IIO_VAL_INT;
> +		default:
> +			return -EINVAL;
> +		}
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static const struct iio_info vcnl3020_info = {
> +	.read_raw = vcnl3020_read_raw,
> +};
> +
> +static const struct regmap_config vcnl3020_regmap_config = {
> +	.reg_bits	= 8,
> +	.val_bits	= 8,
> +	.max_register	= VCNL_PS_MOD_ADJ,
> +};
> +
> +static int vcnl3020_probe(struct i2c_client *client)
> +{
> +	struct vcnl3020_data *data;
> +	struct iio_dev *indio_dev;
> +	struct regmap *regmap;
> +	int rc;
> +
> +	regmap = devm_regmap_init_i2c(client, &vcnl3020_regmap_config);
> +	if (IS_ERR(regmap)) {
> +		dev_err(&client->dev, "regmap_init failed!");
> +		return PTR_ERR(regmap);
> +	}
> +
> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	data = iio_priv(indio_dev);
> +	i2c_set_clientdata(client, indio_dev);
> +	data->regmap = regmap;
> +	data->dev = &client->dev;
> +
> +	rc = vcnl3020_init(data);
> +	if (rc)
> +		return rc;
> +
> +	indio_dev->dev.parent = &client->dev;
> +	indio_dev->info = &vcnl3020_info;
> +	indio_dev->channels = vcnl3020_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(vcnl3020_channels);
> +	indio_dev->name = "vcnl3020";
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	return devm_iio_device_register(&client->dev, indio_dev);
> +}
> +
> +static const struct of_device_id vcnl3020_of_match[] = {
> +	{
> +		.compatible = "vishay,vcnl3020",
> +	},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, vcnl3020_of_match);
> +
> +static struct i2c_driver vcnl3020_driver = {
> +	.driver = {
> +		.name   = "vcnl3020",
> +		.of_match_table = vcnl3020_of_match,
> +	},
> +	.probe_new  = vcnl3020_probe,
> +};
> +module_i2c_driver(vcnl3020_driver);
> +
> +MODULE_AUTHOR("Ivan Mikhaylov <i.mikhaylov@yadro.com>");
> +MODULE_DESCRIPTION("Vishay VCNL3020 proximity sensor driver");
> +MODULE_LICENSE("GPL");

Re: [PATCH v8 1/2] iio: proximity: provide device tree binding document

[Rob Herring]

On Mon, Apr 06, 2020 at 08:20:01PM +0300, Ivan Mikhaylov wrote:
> Mostly standard i2c driver with some additional led-current option
> for vcnl3020.
> 
> Signed-off-by: Ivan Mikhaylov <i.mikhaylov@yadro.com>
> ---
>  .../bindings/iio/proximity/vcnl3020.yaml      | 65 +++++++++++++++++++
>  1 file changed, 65 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml
> 
> diff --git a/Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml b/Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml
> new file mode 100644
> index 000000000000..29ab2dee1694
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/proximity/vcnl3020.yaml
> @@ -0,0 +1,65 @@
> +# SPDX-License-Identifier: GPL-2.0

Dual license as Jonathan said.

> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/proximity/vcnl3020.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Integrated Proximity Sensor With Infrared Emitter
> +
> +maintainers:
> +  - Ivan Mikhaylov <i.mikhaylov@yadro.com>
> +
> +description: |
> +  The VCNL3020 is a fully integrated proximity sensor. Fully integrated means
> +  that the infrared emitter is included in the package. It has 16-bit
> +  resolution. It includes a signal processing IC and features standard I2C
> +  communication interface. It features an interrupt function.
> +
> +  Specifications about the devices can be found at:
> +  https://www.vishay.com/docs/84150/vcnl3020.pdf
> +
> +properties:
> +  compatible:
> +    enum:
> +      - vishay,vcnl3020
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    description: IRQ line for the proximity sensor

Can drop this.

> +    maxItems: 1
> +
> +  vdd-supply:
> +    description: Regulator that provides power to the sensor
> +
> +  vddio-supply:
> +    description: Regulator that provides power to the bus
> +
> +  vishay,led-current-milliamp:
> +    description:
> +        IR LED current value with valid Range = 0 to 20d. e.g. 0 = 0 mA,

Should be indented 2 fewer spaces.

> +        1 = 10 mA, 20 = 200 mA (2 = 20 mA = DEFAULT). LED Current is
> +        limited to 200 mA for values higher than decimal 20.

Use the 'default' property to define the default.

> +    allOf:
> +      - $ref: /schemas/types.yaml#/definitions/uint32

Can drop this as standard units have a type already. However, the 
standard unit is '-microamp', so use that. Also, looks like this is 
in units of register values, not milliamps. Use microamps (e.g. 200000).

> +      - enum: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
> +              18, 19, 20]
> +
> +required:
> +  - compatible
> +  - reg
> +
> +examples:
> +  - |
> +    i2c {
> +
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        proximity@13 {
> +              compatible = "vishay,vcnl3020";
> +              reg = <0x13>;
> +              vishay,led-current-milliamp = <0x14>;
> +        };
> +    };
> -- 
> 2.21.1
>