Re: [PATCH V2 1/2] staging: iio: add driver for isl29028

[Jonathan Cameron <jic23@cam.ac.uk>]

On 4/12/2012 8:08 AM, Laxman Dewangan wrote:
> Intersil's ISL29028 is concurrent Ambient Light and
> Proximity Sensor device.
> Add driver to access the light and IR intensity and
> proximity value via iio interface.

Clean and  mostly fine.  A few issues with abi compliance on frequency
and range control though...
>
> Signed-off-by: Laxman Dewangan<ldewangan@nvidia.com>
> ---
> Taken care of all review comment from Dan.
>
>   drivers/staging/iio/light/Kconfig    |   10 +
>   drivers/staging/iio/light/Makefile   |    1 +
>   drivers/staging/iio/light/isl29028.c |  566 ++++++++++++++++++++++++++++++++++
>   3 files changed, 577 insertions(+), 0 deletions(-)
>   create mode 100644 drivers/staging/iio/light/isl29028.c
>
> diff --git a/drivers/staging/iio/light/Kconfig b/drivers/staging/iio/light/Kconfig
> index e7e9159..53b49f7 100644
> --- a/drivers/staging/iio/light/Kconfig
> +++ b/drivers/staging/iio/light/Kconfig
> @@ -14,6 +14,16 @@ config SENSORS_ISL29018
>            in lux, proximity infrared sensing and normal infrared sensing.
>            Data from sensor is accessible via sysfs.
>
> +config SENSORS_ISL29028
> +	tristate "Intersil ISL29028 Concurrent Light and Proximity Sensor"
> +	depends on I2C
> +	select REGMAP_I2C
> +	help
> +	 Provides driver for the Intersil's ISL29028 device.
> +	 This driver supports the sysfs interface to get the ALS, IR intensity,
> +	 Proximity value via iio. The ISL29028 provides the concurrent sensing
> +	 of ambient light and proximity.
> +
>   config SENSORS_TSL2563
>   	tristate "TAOS TSL2560, TSL2561, TSL2562 and TSL2563 ambient light sensors"
>   	depends on I2C
> diff --git a/drivers/staging/iio/light/Makefile b/drivers/staging/iio/light/Makefile
> index 3011fbf..535d313 100644
> --- a/drivers/staging/iio/light/Makefile
> +++ b/drivers/staging/iio/light/Makefile
> @@ -4,4 +4,5 @@
>
>   obj-$(CONFIG_SENSORS_TSL2563)	+= tsl2563.o
>   obj-$(CONFIG_SENSORS_ISL29018)	+= isl29018.o
> +obj-$(CONFIG_SENSORS_ISL29028)	+= isl29028.o
>   obj-$(CONFIG_TSL2583)	+= tsl2583.o
> diff --git a/drivers/staging/iio/light/isl29028.c b/drivers/staging/iio/light/isl29028.c
> new file mode 100644
> index 0000000..60b868a
> --- /dev/null
> +++ b/drivers/staging/iio/light/isl29028.c
> @@ -0,0 +1,566 @@
> +/*
> + * A iio driver for the light sensor ISL29028.
The ultimate nitpick iio->IIO as it's a TLA
> + * ISL29028 is Concurrent Ambient Light and Proximity Sensor
> + *
> + * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> + * more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program.  If not, see<http://www.gnu.org/licenses/>.
> + */
> +
> +#include<linux/module.h>
> +#include<linux/i2c.h>
> +#include<linux/err.h>
> +#include<linux/mutex.h>
> +#include<linux/delay.h>
> +#include<linux/slab.h>
> +#include<linux/regmap.h>
> +#include "../iio.h"
> +#include "../sysfs.h"
> +
> +#define CONVERSION_TIME_MS		100
> +
> +#define ISL29028_REG_CONFIGURE		0x01
> +
> +#define CONFIGURE_ALS_IR_MODE_ALS	0
> +#define CONFIGURE_ALS_IR_MODE_IR	BIT(0)
> +#define CONFIGURE_ALS_IR_MODE_MASK	BIT(0)
> +
> +#define CONFIGURE_ALS_RANGE_LOW_LUX	0
> +#define CONFIGURE_ALS_RANGE_HIGH_LUX	BIT(1)
> +#define CONFIGURE_ALS_RANGE_MASK	BIT(1)
> +
> +#define CONFIGURE_ALS_DIS		0
> +#define CONFIGURE_ALS_EN		BIT(2)
> +#define CONFIGURE_ALS_EN_MASK		BIT(2)
> +
> +#define CONFIGURE_PROX_DRIVE		BIT(3)
> +
> +#define CONFIGURE_PROX_SLP_SH		4
> +#define CONFIGURE_PROX_SLP_MASK		(7<<  CONFIGURE_PROX_SLP_SH)
> +
> +#define CONFIGURE_PROX_EN		BIT(7)
> +#define CONFIGURE_PROX_EN_MASK		BIT(7)
> +
> +#define ISL29028_REG_INTERRUPT		0x02
> +
> +#define ISL29028_REG_PROX_DATA		0x08
> +#define ISL29028_REG_ALSIR_L		0x09
> +#define ISL29028_REG_ALSIR_U		0x0A
> +
> +#define ISL29028_REG_TEST1_MODE		0x0E
> +#define ISL29028_REG_TEST2_MODE		0x0F
> +
> +#define ISL29028_MAX_REGS		(ISL29028_REG_TEST2_MODE + 1)
> +
> +enum als_ir_mode {
> +	MODE_NONE = 0,
> +	MODE_ALS,
> +	MODE_IR
> +};
> +
> +struct isl29028_chip {
> +	struct device		*dev;
> +	struct mutex		lock;
> +	struct regmap		*regmap;
> +
> +	unsigned int		prox_period;
> +	bool			enable_prox;
> +
> +	int			lux_scale;
> +	int			als_ir_mode;
> +};
> +
> +static int isl29028_set_proxim_period(struct isl29028_chip *chip,
> +			unsigned int period)
> +{
> +	static unsigned int prox_period[] = {800, 400, 200, 100, 75, 50, 12, 0};
> +	int sel;
> +
> +	for (sel = 0; sel<  ARRAY_SIZE(prox_period); ++sel) {
> +		if (period>= prox_period[sel])
> +			break;
> +	}
> +	return regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
> +			CONFIGURE_PROX_SLP_MASK, sel<<  CONFIGURE_PROX_SLP_SH);
> +}
> +
> +static int isl29028_enable_proximity(struct isl29028_chip *chip, bool enable)
> +{
> +	int ret;
> +	int val = 0;
> +
> +	if (enable)
> +		val = CONFIGURE_PROX_EN;
> +	ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
> +			CONFIGURE_PROX_EN_MASK, val);
> +	if (ret<  0)
> +		return ret;
> +
> +	/* Wait for conversion to be complete for first sample */
> +	if (chip->prox_period)
> +		mdelay(chip->prox_period);
> +	return 0;
> +}
> +
> +static int isl29028_set_als_range(struct isl29028_chip *chip, int lux_scale)
> +{
> +	int val = (lux_scale == 2000) ? CONFIGURE_ALS_RANGE_HIGH_LUX :
> +					CONFIGURE_ALS_RANGE_LOW_LUX;
> +
> +	return regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
> +		CONFIGURE_ALS_RANGE_MASK, val);
> +}
> +
> +static int isl29028_set_als_ir_mode(struct isl29028_chip *chip,
> +	enum als_ir_mode mode)
> +{
> +	int ret = 0;
> +
> +	switch (mode) {
> +	case MODE_ALS:
> +		ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
> +			CONFIGURE_ALS_IR_MODE_MASK, CONFIGURE_ALS_IR_MODE_ALS);
> +		if (ret<  0)
> +			return ret;
> +
> +		ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
> +			CONFIGURE_ALS_RANGE_MASK, CONFIGURE_ALS_RANGE_HIGH_LUX);
> +		break;
> +
> +	case MODE_IR:
> +		ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
> +			CONFIGURE_ALS_IR_MODE_MASK, CONFIGURE_ALS_IR_MODE_IR);
> +		break;
> +
> +	case MODE_NONE:
> +		return regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
> +			CONFIGURE_ALS_EN_MASK, CONFIGURE_ALS_DIS);
> +	}
> +
> +	if (ret<  0)
> +		return ret;
> +
> +	/* Enable the ALS/IR */
> +	ret = regmap_update_bits(chip->regmap, ISL29028_REG_CONFIGURE,
> +			CONFIGURE_ALS_EN_MASK, CONFIGURE_ALS_EN);
> +	if (ret<  0)
> +		return ret;
> +
> +	/* Need to wait for conversion time if ALS/IR mode enabled */
> +	mdelay(CONVERSION_TIME_MS);
> +	return 0;
> +}
> +
> +static int isl29028_read_als_ir(struct isl29028_chip *chip, int *als_ir)
> +{
> +	unsigned int lsb;
> +	unsigned int msb;
> +	int ret;
> +
> +	ret = regmap_read(chip->regmap, ISL29028_REG_ALSIR_L,&lsb);
> +	if (ret<  0) {
> +		dev_err(chip->dev,
> +			"Error in reading register ALSIR_L err %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = regmap_read(chip->regmap, ISL29028_REG_ALSIR_U,&msb);
> +	if (ret<  0) {
> +		dev_err(chip->dev,
> +			"Error in reading register ALSIR_U err %d\n", ret);
> +		return ret;
> +	}
> +
> +	*als_ir = ((msb&  0xF)<<  8) | (lsb&  0xFF);
> +	return 0;
> +}
> +
> +static int isl29028_read_proxim(struct isl29028_chip *chip, int *prox)
> +{
> +	unsigned int data;
> +	int ret;
> +
> +	ret = regmap_read(chip->regmap, ISL29028_REG_PROX_DATA,&data);
> +	if (ret<  0) {
> +		dev_err(chip->dev, "Error in reading register %d, error %d\n",
> +				ISL29028_REG_PROX_DATA, ret);
> +		return ret;
> +	}
> +	*prox = data;
> +	return 0;
> +}
> +
> +static int isl29028_proxim_get(struct isl29028_chip *chip, int *prox_data)
> +{
> +	int ret;
> +
> +	if (!chip->enable_prox) {
> +		ret = isl29028_enable_proximity(chip, true);
> +		if (ret<  0)
> +			return ret;
> +		chip->enable_prox = true;
> +	}
> +	return isl29028_read_proxim(chip, prox_data);
> +}
> +
> +static int isl29028_als_get(struct isl29028_chip *chip, int *als_data)
> +{
> +	int ret;
> +	int als_ir_data;
> +
> +	if (chip->als_ir_mode != MODE_ALS) {
> +		ret = isl29028_set_als_ir_mode(chip, MODE_ALS);
> +		if (ret<  0) {
> +			dev_err(chip->dev,
> +				"Error in enabling ALS mode err %d\n", ret);
> +			return ret;
> +		}
> +		chip->als_ir_mode = MODE_ALS;
> +	}
> +
> +	ret = isl29028_read_als_ir(chip,&als_ir_data);
> +	if (ret<  0)
> +		return ret;
> +
> +	/*
> +	 * convert als data count to lux.
> +	 * if lux_scale = 125,  lux = count * 0.031
> +	 * if lux_scale = 2000, lux = count * 0.49
> +	 */
> +	if (chip->lux_scale == 125)
> +		als_ir_data = (als_ir_data * 31) / 1000;
> +	else
> +		als_ir_data = (als_ir_data * 49) / 100;
> +
> +	*als_data = als_ir_data;
> +	return 0;
> +}
> +
> +static int isl29028_ir_get(struct isl29028_chip *chip, int *ir_data)
> +{
> +	int ret;
> +
> +	if (chip->als_ir_mode != MODE_IR) {
> +		ret = isl29028_set_als_ir_mode(chip, MODE_IR);
> +		if (ret<  0) {
> +			dev_err(chip->dev,
> +				"Error in enabling IR mode err %d\n", ret);
> +			return ret;
> +		}
> +		chip->als_ir_mode = MODE_IR;
> +	}
> +	return isl29028_read_als_ir(chip, ir_data);
> +}
> +
> +/* Sysfs interface */
> +/* proximity sampling period  */
> +static ssize_t show_prox_period(struct device *dev,
> +	struct device_attribute *attr, char *buf)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct isl29028_chip *chip = iio_priv(indio_dev);
> +
> +	return sprintf(buf, "%u\n", chip->prox_period);
> +}
> +
> +static ssize_t store_prox_period(struct device *dev,
> +		struct device_attribute *attr, const char *buf, size_t count)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct isl29028_chip *chip = iio_priv(indio_dev);
> +	unsigned int uival;
> +	int ret;
> +
> +	ret = kstrtouint(buf, 10,&uival);
> +	if (ret<  0) {
> +		dev_err(dev, "Error in parsing the input buffer\n");
> +		return ret;
> +	}
> +
> +	if (uival>  800) {
> +		dev_err(dev, "Period %u is not in range[0:800]\n", uival);
> +		return -EINVAL;
> +	}
> +
> +	mutex_lock(&chip->lock);
> +	ret = isl29028_set_proxim_period(chip, uival);
> +	if (ret<  0) {
> +		dev_err(dev, "Error in setting the proximity period\n");
> +		return ret;
> +	}
> +	chip->prox_period = uival;
> +	mutex_unlock(&chip->lock);
> +
> +	return count;
> +}
> +
> +/* als range  */
> +static ssize_t show_range(struct device *dev,
> +	struct device_attribute *attr, char *buf)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct isl29028_chip *chip = iio_priv(indio_dev);
> +	return sprintf(buf, "%d\n", chip->lux_scale);
> +}
> +
> +static ssize_t store_range(struct device *dev,
> +		struct device_attribute *attr, const char *buf, size_t count)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct isl29028_chip *chip = iio_priv(indio_dev);
> +	int ival;
> +	int ret;
> +
> +	ret = kstrtoint(buf, 10,&ival);
> +	if (ret<  0) {
> +		dev_err(dev, "Error in parsing input buffer ret = %d\n", ret);
> +		return ret;
> +	}
> +
> +	if ((ival != 125)&&  (ival != 2000)) {
> +		dev_err(dev, "Invalid options %d [125, 2000]\n", ival);
> +		return -EINVAL;
> +	}
> +
> +	mutex_lock(&chip->lock);
> +	ret = isl29028_set_als_range(chip, ival);
> +	if (ret<  0) {
> +		dev_err(dev, "Error in setting the range\n");
> +		return ret;
> +	}
> +	chip->lux_scale = ival;
> +	mutex_unlock(&chip->lock);
> +	return count;
> +}
> +
> +/* Channel IO */
> +static int isl29028_read_raw(struct iio_dev *indio_dev,
> +	     struct iio_chan_spec const *chan, int *val, int *val2, long mask)
> +{
> +	int ret = -EINVAL;
> +	struct isl29028_chip *chip = iio_priv(indio_dev);
> +
> +	mutex_lock(&chip->lock);
> +	switch (mask) {
> +	case 0:
> +		switch (chan->type) {
> +		case IIO_LIGHT:
> +			ret = isl29028_als_get(chip, val);
> +			break;
> +		case IIO_INTENSITY:
> +			ret = isl29028_ir_get(chip, val);
> +			break;
> +		case IIO_PROXIMITY:
> +			ret = isl29028_proxim_get(chip, val);
> +			break;
> +		default:
> +			break;
> +		}
> +		if (ret<  0)
> +			break;
> +		ret = IIO_VAL_INT;
> +		break;
> +
> +	default:
> +		break;
> +	}
> +	mutex_unlock(&chip->lock);
> +	return ret;
> +}
> +
I've not data sheet dived enough to pin down what this is.  If it is 
related to how
often a reading is taken then it should be 
in_proximity0_sampling_frequency   (in Hz)
If that is the case I'd add a sampling frequency element to the 
info_mask (I'm sure
this isn't the last time we will see a frequency control applying to a 
subset of channels)

I see there is also control of the number of samples that must be high 
for events to
happen.  Now that one is called period in is in seconds.
> +static IIO_DEVICE_ATTR(proximity_sampling_period, S_IRUGO | S_IWUSR,
> +				show_prox_period, store_prox_period, 0);
> +static IIO_CONST_ATTR(proximity_sampling_period_available,
> +				"800, 400, 200, 100, 75, 50, 12, 0");
> +
range of what?  Preference is for scale instead and should probably be 
per channel,
done through the info_mask.
> +static IIO_DEVICE_ATTR(range, S_IRUGO | S_IWUSR,
> +				show_range, store_range, 0);
> +static IIO_CONST_ATTR(range_available, "125, 2000");
> +
> +#define ISL29028_DEV_ATTR(name) (&iio_dev_attr_##name.dev_attr.attr)
> +#define ISL29028_CONST_ATTR(name) (&iio_const_attr_##name.dev_attr.attr)
> +static struct attribute *isl29028_attributes[] = {
> +	ISL29028_DEV_ATTR(proximity_sampling_period),
> +	ISL29028_CONST_ATTR(proximity_sampling_period_available),
> +	ISL29028_DEV_ATTR(range),
> +	ISL29028_CONST_ATTR(range_available),
> +	NULL,
> +};
> +
> +static const struct attribute_group isl29108_group = {
> +	.attrs = isl29028_attributes,
> +};
> +
> +static const struct iio_chan_spec isl29028_channels[] = {
> +	{
> +		.type = IIO_LIGHT,
> +		.processed_val = 1,
> +	}, {
> +		.type = IIO_INTENSITY,
> +	}, {
> +		.type = IIO_PROXIMITY,
> +	}
> +};
There's a bit of a rework going on over how this handled so you might
hit that if it merges before you do. If not I'll fixup as necessary.
> +
> +static const struct iio_info isl29028_info = {
> +	.attrs =&isl29108_group,
> +	.driver_module = THIS_MODULE,
> +	.read_raw =&isl29028_read_raw,
> +};
> +
> +static int isl29028_chip_init(struct isl29028_chip *chip)
> +{
> +	int ret;
> +
> +	chip->enable_prox  = false;
> +	chip->prox_period = 50;
> +	chip->lux_scale = 2000;
> +	chip->als_ir_mode = MODE_NONE;
> +
> +	ret = regmap_write(chip->regmap, ISL29028_REG_TEST1_MODE, 0x0);
> +	if (ret<  0) {
> +		dev_err(chip->dev, "%s(): write to reg %d failed, err = %d\n",
> +			__func__, ISL29028_REG_TEST1_MODE, ret);
> +		return ret;
> +	}
> +	ret = regmap_write(chip->regmap, ISL29028_REG_TEST2_MODE, 0x0);
> +	if (ret<  0) {
> +		dev_err(chip->dev, "%s(): write to reg %d failed, err = %d\n",
> +			__func__, ISL29028_REG_TEST2_MODE, ret);
> +		return ret;
> +	}
> +
> +	ret = regmap_write(chip->regmap, ISL29028_REG_CONFIGURE, 0x0);
> +	if (ret<  0) {
> +		dev_err(chip->dev, "%s(): write to reg %d failed, err = %d\n",
> +			__func__, ISL29028_REG_CONFIGURE, ret);
> +		return ret;
> +	}
> +
> +	ret = isl29028_set_als_range(chip, chip->lux_scale);
> +	if (ret<  0)
> +		dev_err(chip->dev, "%s(): setting als range failed, err = %d\n",
> +			__func__, ret);
> +	return ret;
> +}
> +
> +static bool is_volatile_reg(struct device *dev, unsigned int reg)
> +{
> +	switch (reg) {
> +	case ISL29028_REG_INTERRUPT:
> +	case ISL29028_REG_PROX_DATA:
> +	case ISL29028_REG_ALSIR_L:
> +	case ISL29028_REG_ALSIR_U:
> +		return true;
> +	default:
> +		return false;
> +	}
> +}
> +
> +static const struct regmap_config isl29028_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +	.volatile_reg = is_volatile_reg,
> +	.max_register = ISL29028_MAX_REGS - 1,
> +	.num_reg_defaults_raw = ISL29028_MAX_REGS,
> +	.cache_type = REGCACHE_RBTREE,
> +};
> +
> +static int __devinit isl29028_probe(struct i2c_client *client,
> +	const struct i2c_device_id *id)
> +{
> +	struct isl29028_chip *chip;
> +	struct iio_dev *indio_dev;
> +	int ret;
> +
> +	indio_dev = iio_allocate_device(sizeof(*chip));
> +	if (!indio_dev) {
> +		dev_err(&client->dev, "iio allocation fails\n");
> +		return -ENOMEM;
> +	}
> +
> +	chip = iio_priv(indio_dev);
> +
> +	i2c_set_clientdata(client, indio_dev);
> +	chip->dev =&client->dev;
> +	mutex_init(&chip->lock);
> +
> +	chip->regmap = devm_regmap_init_i2c(client,&isl29028_regmap_config);
> +	if (IS_ERR(chip->regmap)) {
> +		ret = PTR_ERR(chip->regmap);
> +		dev_err(chip->dev, "regmap initialization failed: %d\n", ret);
> +		goto exit_iio_free;
> +	}
> +
> +	ret = isl29028_chip_init(chip);
> +	if (ret<  0) {
> +		dev_err(chip->dev, "chip initialization failed: %d\n", ret);
> +		goto exit_iio_free;
> +	}
> +
> +	indio_dev->info =&isl29028_info;
> +	indio_dev->channels = isl29028_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(isl29028_channels);
> +	indio_dev->name = id->name;
> +	indio_dev->dev.parent =&client->dev;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +	ret = iio_device_register(indio_dev);
> +	if (ret<  0) {
> +		dev_err(chip->dev, "iio registration fails\n");
> +		goto exit_iio_free;
> +	}
> +	return 0;
> +
> +exit_iio_free:
> +	iio_free_device(indio_dev);
> +	return ret;
> +}
> +
> +static int __devexit isl29028_remove(struct i2c_client *client)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> +	iio_device_unregister(indio_dev);
> +	iio_free_device(indio_dev);
> +	return 0;
> +}
> +
> +static const struct i2c_device_id isl29028_id[] = {
> +	{"isl29028", 0},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, isl29028_id);
> +
> +static const struct of_device_id isl29028_of_match[] = {
> +	{ .compatible = "isl,isl29028", },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, isl29028_of_match);
> +
> +static struct i2c_driver isl29028_driver = {
> +	.class	= I2C_CLASS_HWMON,
> +	.driver  = {
> +		.name = "isl29028",
> +		.owner = THIS_MODULE,
> +		.of_match_table = isl29028_of_match,
> +	},
> +	.probe	 = isl29028_probe,
> +	.remove  = __devexit_p(isl29028_remove),
> +	.id_table = isl29028_id,
> +};
> +
> +module_i2c_driver(isl29028_driver);
> +
> +MODULE_DESCRIPTION("ISL29028 Ambient Light and Proximity Sensor driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Laxman Dewangan<ldewangan@nvidia.com>");