Re: [PATCH] iio: add vcnl4000 combined ALS and proximity sensor

[Jonathan Cameron <jic23@kernel.org>]

On 6/17/2012 2:19 PM, Peter Meerwald wrote:
> minimal driver, no IR current control and proximity/event handling
> yet
>
> v4 (address comments by Jonathan Cameron)
> * remove SENSORS_ prefix in Kconfig
> * change from IIO_INTENSITY to IIO_LIGHT
> * move from staging
>
> v3 (address comments by Shubhrajyoti Datta)
> * cleanup Kconfig entry
> * call I2C read/write functions directly
>
> v2 (address comments by Lars-Peter Clausen and Jonathan Cameron)
> * unify code for reading PS and AL data into
>    parameterized _measure() function
> * limit wait for data to become ready within 20 tries
> * drop IIO_LIGHT channel, add SCALE to IIO_INTENSITY
> * drop extra string arguments used for logging purpose only
>
> Signed-off-by: Peter Meerwald<pmeerw@pmeerw.net>
Acked-by: Jonathan Cameron <jic23@kernel.org>
> ---
>   drivers/iio/light/Kconfig    |   11 +++
>   drivers/iio/light/Makefile   |    1 +
>   drivers/iio/light/vcnl4000.c |  216 ++++++++++++++++++++++++++++++++++++++++++
>   3 files changed, 228 insertions(+)
>   create mode 100644 drivers/iio/light/vcnl4000.c
>
> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
> index db5618e..f3ea90d 100644
> --- a/drivers/iio/light/Kconfig
> +++ b/drivers/iio/light/Kconfig
> @@ -19,4 +19,15 @@ config SENSORS_LM3533
>   	  light zone through sysfs. A threshold event can be generated on zone
>   	  changes. The ALS-control output values can be set per zone for the
>   	  three current output channels.
> +
> +config VCNL4000
> +	tristate "VCNL4000 combined ALS and proximity sensor"
> +	depends on I2C
> +	help
> +	 Say Y here if you want to build a driver for the Vishay VCNL4000
> +	 combined ambient light and proximity sensor.
> +
> +	 To compile this driver as a module, choose M here: the
> +	 module will be called vcnl4000.
> +
>   endmenu
> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
> index c1c23a0..06fa4d3 100644
> --- a/drivers/iio/light/Makefile
> +++ b/drivers/iio/light/Makefile
> @@ -3,3 +3,4 @@
>   #
>
>   obj-$(CONFIG_SENSORS_LM3533)	+= lm3533-als.o
> +obj-$(CONFIG_VCNL4000)		+= vcnl4000.o
> diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
> new file mode 100644
> index 0000000..c278495
> --- /dev/null
> +++ b/drivers/iio/light/vcnl4000.c
> @@ -0,0 +1,216 @@
> +/*
> + * vcnl4000.c - Support for Vishay VCNL4000 combined ambient light and
> + * proximity sensor
> + *
> + * Copyright 2012 Peter Meerwald<pmeerw@pmeerw.net>
> + *
> + * This file is subject to the terms and conditions of version 2 of
> + * the GNU General Public License.  See the file COPYING in the main
> + * directory of this archive for more details.
> + *
> + * IIO driver for VCNL4000 (7-bit I2C slave address 0x13)
> + *
> + * TODO:
> + *   allow to adjust IR current
> + *   proximity threshold and event handling
> + */
> +
> +#include<linux/module.h>
> +#include<linux/i2c.h>
> +#include<linux/err.h>
> +#include<linux/delay.h>
> +
> +#include<linux/iio/iio.h>
> +#include<linux/iio/sysfs.h>
> +
> +#define VCNL4000_DRV_NAME "vcnl4000"
> +
> +#define VCNL4000_COMMAND	0x80 /* Command register */
> +#define VCNL4000_PROD_REV	0x81 /* Product ID and Revision ID */
> +#define VCNL4000_LED_CURRENT	0x83 /* IR LED current for proximity mode */
> +#define VCNL4000_AL_PARAM	0x84 /* Ambient light parameter register */
> +#define VCNL4000_AL_RESULT_HI	0x85 /* Ambient light result register, MSB */
> +#define VCNL4000_AL_RESULT_LO	0x86 /* Ambient light result register, LSB */
> +#define VCNL4000_PS_RESULT_HI	0x87 /* Proximity result register, MSB */
> +#define VCNL4000_PS_RESULT_LO	0x88 /* Proximity result register, LSB */
> +#define VCNL4000_PS_MEAS_FREQ	0x89 /* Proximity measurement signal frequency */
> +#define VCNL4000_PS_MOD_ADJ	0x8a /* Proximity modulator timing adjustment */
> +
> +/* Bit masks for COMMAND register */
> +#define VCNL4000_AL_RDY		0x40 /* ALS data ready? */
> +#define VCNL4000_PS_RDY		0x20 /* proximity data ready? */
> +#define VCNL4000_AL_OD		0x10 /* start on-demand ALS measurement */
> +#define VCNL4000_PS_OD		0x08 /* start on-demand proximity measurement */
> +
> +struct vcnl4000_data {
> +	struct i2c_client *client;
> +};
> +
> +static const struct i2c_device_id vcnl4000_id[] = {
> +	{ "vcnl4000", 0 },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(i2c, vcnl4000_id);
> +
> +static int vcnl4000_measure(struct vcnl4000_data *data, u8 req_mask,
> +				u8 rdy_mask, u8 data_reg, int *val)
> +{
> +	int tries = 20;
> +	u16 buf;
> +	int ret;
> +
> +	ret = i2c_smbus_write_byte_data(data->client, VCNL4000_COMMAND, req_mask);
> +	if (ret<  0)
> +		return ret;
> +
> +	/* wait for data to become ready */
> +	while (tries--) {
> +		ret = i2c_smbus_read_byte_data(data->client, VCNL4000_COMMAND);
> +		if (ret<  0)
> +			return ret;
> +		if (ret&  rdy_mask)
> +			break;
> +		msleep(1);
> +	}
> +
> +	if (tries<  0) {
> +		dev_err(&data->client->dev,
> +			"vcnl4000_measure() failed, data not ready\n");
> +		return -EIO;
> +	}
> +
> +	ret = i2c_smbus_read_i2c_block_data(data->client,
> +		data_reg, sizeof(buf), (u8 *)&buf);
> +	if (ret<  0)
> +		return ret;
> +
> +	*val = be16_to_cpu(buf);
> +
> +	return 0;
> +}
> +
> +static const struct iio_chan_spec vcnl4000_channels[] = {
> +	{
> +		.type = IIO_LIGHT,
> +		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
> +			IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
> +	}, {
> +		.type = IIO_PROXIMITY,
> +		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT,
> +	}
> +};
> +
> +static int vcnl4000_read_raw(struct iio_dev *indio_dev,
> +				struct iio_chan_spec const *chan,
> +				int *val, int *val2, long mask)
> +{
> +	int ret = -EINVAL;
> +	struct vcnl4000_data *data = iio_priv(indio_dev);
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		switch (chan->type) {
> +		case IIO_LIGHT:
> +			ret = vcnl4000_measure(data,
> +				VCNL4000_AL_OD, VCNL4000_AL_RDY,
> +				VCNL4000_AL_RESULT_HI, val);
> +			if (ret<  0)
> +				return ret;
> +			ret = IIO_VAL_INT;
> +			break;
> +		case IIO_PROXIMITY:
> +			ret = vcnl4000_measure(data,
> +				VCNL4000_PS_OD, VCNL4000_PS_RDY,
> +				VCNL4000_PS_RESULT_HI, val);
> +			if (ret<  0)
> +				return ret;
> +			ret = IIO_VAL_INT;
> +			break;
> +		default:
> +			break;
> +		}
> +		break;
> +	case IIO_CHAN_INFO_SCALE:
> +		if (chan->type == IIO_LIGHT) {
> +			*val = 0;
> +			*val2 = 250000;
> +			ret = IIO_VAL_INT_PLUS_MICRO;
> +		}
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	return ret;
> +}
> +
> +static const struct iio_info vcnl4000_info = {
> +	.read_raw = vcnl4000_read_raw,
> +	.driver_module = THIS_MODULE,
> +};
> +
> +static int __devinit vcnl4000_probe(struct i2c_client *client,
> +					const struct i2c_device_id *id)
> +{
> +	struct vcnl4000_data *data;
> +	struct iio_dev *indio_dev;
> +	int ret;
> +
> +	indio_dev = iio_device_alloc(sizeof(*data));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	data = iio_priv(indio_dev);
> +	i2c_set_clientdata(client, indio_dev);
> +	data->client = client;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, VCNL4000_PROD_REV);
> +	if (ret<  0)
> +		goto error_free_dev;
> +
> +	dev_info(&client->dev, "VCNL4000 Ambient light/proximity sensor, "
> +		"Prod %02x, Rev: %02x\n", ret>>  4, ret&  0xf);
> +
> +	indio_dev->dev.parent =&client->dev;
> +	indio_dev->info =&vcnl4000_info;
> +	indio_dev->channels = vcnl4000_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(vcnl4000_channels);
> +	indio_dev->name = VCNL4000_DRV_NAME;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	ret = iio_device_register(indio_dev);
> +	if (ret<  0)
> +		goto error_free_dev;
> +
> +	return 0;
> +
> +error_free_dev:
> +	iio_device_free(indio_dev);
> +	return ret;
> +}
> +
> +static int __devexit vcnl4000_remove(struct i2c_client *client)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> +	iio_device_unregister(indio_dev);
> +	iio_device_free(indio_dev);
> +
> +	return 0;
> +}
> +
> +static struct i2c_driver vcnl4000_driver = {
> +	.driver = {
> +		.name   = VCNL4000_DRV_NAME,
> +		.owner  = THIS_MODULE,
> +	},
> +	.probe  = vcnl4000_probe,
> +	.remove = __devexit_p(vcnl4000_remove),
> +	.id_table = vcnl4000_id,
> +};
> +
> +module_i2c_driver(vcnl4000_driver);
> +
> +MODULE_AUTHOR("Peter Meerwald<pmeerw@pmeerw.net>");
> +MODULE_DESCRIPTION("Vishay VCNL4000 proximity/ambient light sensor driver");
> +MODULE_LICENSE("GPL");