[PATCH V3 0/2] staging: iio: add isl29028 driver

[PATCH V3 0/2] staging: iio: add isl29028 driver

[Laxman Dewangan]

ISL29028 is concurrent Ambient light and proximity sensor
from intersil.
Adding driver for supporting this device.

Changes from V1:
- Taken care of cleanups comments.

Changes from V2:
- Implement the sampling frequency selection per channel wise.
- Remove documentation change as it is already there.
- Use the channel info for selecting proximity sampling rather than
  exposing new sysfs from driver.


Laxman Dewangan (2):
  staging: iio: add channel info for sampling frequency
  staging: iio: add driver for isl29028

 drivers/staging/iio/iio.h               |    5 +
 drivers/staging/iio/industrialio-core.c |    1 +
 drivers/staging/iio/light/Kconfig       |   10 +
 drivers/staging/iio/light/Makefile      |    1 +
 drivers/staging/iio/light/isl29028.c    |  574 +++++++++++++++++++++++++++++++
 5 files changed, 591 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/iio/light/isl29028.c

[PATCH V3 1/2] staging: iio: add channel info for sampling frequency

[Laxman Dewangan]

Adding channel info IIO_CHAN_INFO_SAMP_FREQ to select
different sampling frequency per channel wise.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
---
As per discussion on previous patch, adding channel info
for selecting sampling freqeuncy.

 drivers/staging/iio/iio.h               |    5 +++++
 drivers/staging/iio/industrialio-core.c |    1 +
 2 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/staging/iio/iio.h b/drivers/staging/iio/iio.h
index b9cd454..9aa0dd5 100644
--- a/drivers/staging/iio/iio.h
+++ b/drivers/staging/iio/iio.h
@@ -36,6 +36,7 @@ enum iio_chan_info_enum {
 	IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW,
 	IIO_CHAN_INFO_AVERAGE_RAW,
 	IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY,
+	IIO_CHAN_INFO_SAMP_FREQ,
 };
 
 #define IIO_CHAN_INFO_SHARED_BIT(type) BIT(type*2)
@@ -81,6 +82,10 @@ enum iio_chan_info_enum {
 #define IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SEPARATE_BIT \
 	IIO_CHAN_INFO_SEPARATE_BIT(			       \
 		IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY)
+#define IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT		\
+	IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_SAMP_FREQ)
+#define IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT			\
+	IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_SAMP_FREQ)
 
 enum iio_endian {
 	IIO_CPU,
diff --git a/drivers/staging/iio/industrialio-core.c b/drivers/staging/iio/industrialio-core.c
index d303bfb..14ce6ce 100644
--- a/drivers/staging/iio/industrialio-core.c
+++ b/drivers/staging/iio/industrialio-core.c
@@ -90,6 +90,7 @@ static const char * const iio_chan_info_postfix[] = {
 	[IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
 	[IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
 	= "filter_low_pass_3db_frequency",
+	[IIO_CHAN_INFO_SAMP_FREQ] = "samp_freq",
 };
 
 const struct iio_chan_spec
-- 
1.7.1.1

Re: [PATCH V3 1/2] staging: iio: add channel info for sampling frequency

[Jonathan Cameron]

On 4/12/2012 1:38 PM, Laxman Dewangan wrote:
> Adding channel info IIO_CHAN_INFO_SAMP_FREQ to select
> different sampling frequency per channel wise.
>
> Signed-off-by: Laxman Dewangan<ldewangan@nvidia.com>
> ---
> As per discussion on previous patch, adding channel info
> for selecting sampling freqeuncy.
To match with the existing devices can we not use the abrieviation
for the attribute naming.

Other than that, all good.
>   drivers/staging/iio/iio.h               |    5 +++++
>   drivers/staging/iio/industrialio-core.c |    1 +
>   2 files changed, 6 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/staging/iio/iio.h b/drivers/staging/iio/iio.h
> index b9cd454..9aa0dd5 100644
> --- a/drivers/staging/iio/iio.h
> +++ b/drivers/staging/iio/iio.h
> @@ -36,6 +36,7 @@ enum iio_chan_info_enum {
>   	IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW,
>   	IIO_CHAN_INFO_AVERAGE_RAW,
>   	IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY,
> +	IIO_CHAN_INFO_SAMP_FREQ,
>   };
>
>   #define IIO_CHAN_INFO_SHARED_BIT(type) BIT(type*2)
> @@ -81,6 +82,10 @@ enum iio_chan_info_enum {
>   #define IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SEPARATE_BIT \
>   	IIO_CHAN_INFO_SEPARATE_BIT(			       \
>   		IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY)
> +#define IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT		\
> +	IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_SAMP_FREQ)
> +#define IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT			\
> +	IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_SAMP_FREQ)
>
>   enum iio_endian {
>   	IIO_CPU,
> diff --git a/drivers/staging/iio/industrialio-core.c b/drivers/staging/iio/industrialio-core.c
> index d303bfb..14ce6ce 100644
> --- a/drivers/staging/iio/industrialio-core.c
> +++ b/drivers/staging/iio/industrialio-core.c
> @@ -90,6 +90,7 @@ static const char * const iio_chan_info_postfix[] = {
>   	[IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
>   	[IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
>   	= "filter_low_pass_3db_frequency",
> +	[IIO_CHAN_INFO_SAMP_FREQ] = "samp_freq",
"sampling_frequency"
>   };
>
>   const struct iio_chan_spec

Re: [PATCH V3 1/2] staging: iio: add channel info for sampling frequency

[Laxman Dewangan]

On Thursday 12 April 2012 06:45 PM, Jonathan Cameron wrote:
> On 4/12/2012 1:38 PM, Laxman Dewangan wrote:
>> Adding channel info IIO_CHAN_INFO_SAMP_FREQ to select
>> different sampling frequency per channel wise.
>>
>> Signed-off-by: Laxman Dewangan<ldewangan@nvidia.com>
>> ---
>> As per discussion on previous patch, adding channel info
>> for selecting sampling freqeuncy.
> To match with the existing devices can we not use the abrieviation
> for the attribute naming.
>

Sorry..I did not get it completely.
Is it like we should have IIO_CHAN_INFO_SAMPLING_FREQUENCY in place of  
IIO_CHAN_INFO_SAMP_FREQ?


>> @@ -90,6 +90,7 @@ static const char * const iio_chan_info_postfix[] = {
>>    	[IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
>>    	[IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
>>    	= "filter_low_pass_3db_frequency",
>> +	[IIO_CHAN_INFO_SAMP_FREQ] = "samp_freq",
> "sampling_frequency"

and then change here as "sampling_frequency"?

Re: [PATCH V3 1/2] staging: iio: add channel info for sampling frequency

[Jonathan Cameron]

On 4/12/2012 2:09 PM, Laxman Dewangan wrote:
> On Thursday 12 April 2012 06:45 PM, Jonathan Cameron wrote:
>> On 4/12/2012 1:38 PM, Laxman Dewangan wrote:
>>> Adding channel info IIO_CHAN_INFO_SAMP_FREQ to select
>>> different sampling frequency per channel wise.
>>>
>>> Signed-off-by: Laxman Dewangan<ldewangan@nvidia.com>
>>> ---
>>> As per discussion on previous patch, adding channel info
>>> for selecting sampling freqeuncy.
>> To match with the existing devices can we not use the abrieviation
>> for the attribute naming.
>>
>
> Sorry..I did not get it completely.
> Is it like we should have IIO_CHAN_INFO_SAMPLING_FREQUENCY in place 
> of  IIO_CHAN_INFO_SAMP_FREQ?
SAMP_FREQ is fine internally.
>
>
>>> @@ -90,6 +90,7 @@ static const char * const iio_chan_info_postfix[] = {
>>>        [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
>>>        [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
>>>        = "filter_low_pass_3db_frequency",
>>> +    [IIO_CHAN_INFO_SAMP_FREQ] = "samp_freq",
>> "sampling_frequency"
>
> and then change here as "sampling_frequency"?
>
Yup, that's the one that is (in the general all channels case) already 
in the abi docs...
>
>
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[PATCH V3 2/2] staging: iio: add driver for isl29028

[Laxman Dewangan]

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.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
---
Changes from V1:
- Taken care of cleanups comments.
Changes from V2:
- use the channel info for sampling frequency selection rather than
 exposing separate sysfs from driver.

 drivers/staging/iio/light/Kconfig    |   10 +
 drivers/staging/iio/light/Makefile   |    1 +
 drivers/staging/iio/light/isl29028.c |  574 ++++++++++++++++++++++++++++++++++
 3 files changed, 585 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..73f6fdc
--- /dev/null
+++ b/drivers/staging/iio/light/isl29028.c
@@ -0,0 +1,574 @@
+/*
+ * IIO driver for the light sensor ISL29028.
+ * 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_sampling;
+	bool			enable_prox;
+
+	int			lux_scale;
+	int			als_ir_mode;
+};
+
+static int isl29028_set_proxim_sampling(struct isl29028_chip *chip,
+			unsigned int sampling)
+{
+	static unsigned int prox_period[] = {800, 400, 200, 100, 75, 50, 12, 0};
+	int sel;
+	unsigned int period = DIV_ROUND_UP(1000, sampling);
+
+	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 */
+	mdelay(DIV_ROUND_UP(1000, chip->prox_sampling));
+	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 */
+/* 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_write_raw(struct iio_dev *indio_dev,
+	     struct iio_chan_spec const *chan, int val, int val2, long mask)
+{
+	struct isl29028_chip *chip = iio_priv(indio_dev);
+	int ret = -EINVAL;
+
+	mutex_lock(&chip->lock);
+	switch (chan->type) {
+	case IIO_PROXIMITY:
+		if (mask != IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT) {
+			dev_err(chip->dev,
+				"mask value 0x%08lx not supported\n", mask);
+			break;
+		}
+		if (val < 1 || val > 100) {
+			dev_err(chip->dev,
+				"Sampling %d is not in range[1:100]\n", val);
+			break;
+		}
+		ret = isl29028_set_proxim_sampling(chip, val);
+		if (ret < 0) {
+			dev_err(chip->dev,
+				"Error in setting the proximity sampling\n");
+			break;
+		}
+		chip->prox_sampling = val;
+		break;
+
+	default:
+		dev_err(chip->dev, "Unsupported channel type\n");
+		break;
+	}
+	mutex_unlock(&chip->lock);
+	return ret;
+}
+
+static int isl29028_read_raw(struct iio_dev *indio_dev,
+	     struct iio_chan_spec const *chan, int *val, int *val2, long mask)
+{
+	struct isl29028_chip *chip = iio_priv(indio_dev);
+	int ret = -EINVAL;
+
+	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;
+
+	case IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT:
+		if (chan->type != IIO_PROXIMITY)
+			break;
+		*val = chip->prox_sampling;
+		ret = IIO_VAL_INT;
+		break;
+
+	default:
+		dev_err(chip->dev, "mask value 0x%08lx not supported\n", mask);
+		break;
+	}
+	mutex_unlock(&chip->lock);
+	return ret;
+}
+
+static IIO_CONST_ATTR(proximity_samp_freq_available,
+				"1, 3, 5, 10, 13, 20, 83, 100");
+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_CONST_ATTR(proximity_samp_freq_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,
+		.info_mask = IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT,
+	}
+};
+
+static const struct iio_info isl29028_info = {
+	.attrs = &isl29108_group,
+	.driver_module = THIS_MODULE,
+	.read_raw = &isl29028_read_raw,
+	.write_raw = &isl29028_write_raw,
+};
+
+static int isl29028_chip_init(struct isl29028_chip *chip)
+{
+	int ret;
+
+	chip->enable_prox  = false;
+	chip->prox_sampling = 20;
+	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_proxim_sampling(chip, chip->prox_sampling);
+	if (ret < 0) {
+		dev_err(chip->dev, "%s(): setting the proximity, err = %d\n",
+			__func__, 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>");
-- 
1.7.1.1

Re: [PATCH V3 2/2] staging: iio: add driver for isl29028

[Jonathan Cameron]

On 4/12/2012 1:38 PM, 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.
I think you missed the comments about the range attributes in the last
review...
>
> Signed-off-by: Laxman Dewangan<ldewangan@nvidia.com>
> ---
> Changes from V1:
> - Taken care of cleanups comments.
> Changes from V2:
> - use the channel info for sampling frequency selection rather than
>   exposing separate sysfs from driver.
>
>   drivers/staging/iio/light/Kconfig    |   10 +
>   drivers/staging/iio/light/Makefile   |    1 +
>   drivers/staging/iio/light/isl29028.c |  574 ++++++++++++++++++++++++++++++++++
>   3 files changed, 585 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..73f6fdc
> --- /dev/null
> +++ b/drivers/staging/iio/light/isl29028.c
> @@ -0,0 +1,574 @@
> +/*
> + * IIO driver for the light sensor ISL29028.
> + * 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_sampling;
> +	bool			enable_prox;
> +
> +	int			lux_scale;
> +	int			als_ir_mode;
> +};
> +
> +static int isl29028_set_proxim_sampling(struct isl29028_chip *chip,
> +			unsigned int sampling)
> +{
> +	static unsigned int prox_period[] = {800, 400, 200, 100, 75, 50, 12, 0};
> +	int sel;
> +	unsigned int period = DIV_ROUND_UP(1000, sampling);
> +
> +	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 */
> +	mdelay(DIV_ROUND_UP(1000, chip->prox_sampling));
> +	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 */
> +/* 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_write_raw(struct iio_dev *indio_dev,
> +	     struct iio_chan_spec const *chan, int val, int val2, long mask)
> +{
> +	struct isl29028_chip *chip = iio_priv(indio_dev);
> +	int ret = -EINVAL;
> +
> +	mutex_lock(&chip->lock);
> +	switch (chan->type) {
> +	case IIO_PROXIMITY:
> +		if (mask != IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT) {
> +			dev_err(chip->dev,
> +				"mask value 0x%08lx not supported\n", mask);
> +			break;
> +		}
> +		if (val<  1 || val>  100) {
> +			dev_err(chip->dev,
> +				"Sampling %d is not in range[1:100]\n", val);
> +			break;
> +		}
> +		ret = isl29028_set_proxim_sampling(chip, val);
> +		if (ret<  0) {
> +			dev_err(chip->dev,
> +				"Error in setting the proximity sampling\n");
> +			break;
> +		}
> +		chip->prox_sampling = val;
> +		break;
> +
> +	default:
> +		dev_err(chip->dev, "Unsupported channel type\n");
> +		break;
> +	}
> +	mutex_unlock(&chip->lock);
> +	return ret;
> +}
> +
> +static int isl29028_read_raw(struct iio_dev *indio_dev,
> +	     struct iio_chan_spec const *chan, int *val, int *val2, long mask)
> +{
> +	struct isl29028_chip *chip = iio_priv(indio_dev);
> +	int ret = -EINVAL;
> +
> +	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;
> +
> +	case IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT:
> +		if (chan->type != IIO_PROXIMITY)
> +			break;
> +		*val = chip->prox_sampling;
> +		ret = IIO_VAL_INT;
> +		break;
> +
> +	default:
> +		dev_err(chip->dev, "mask value 0x%08lx not supported\n", mask);
> +		break;
> +	}
> +	mutex_unlock(&chip->lock);
> +	return ret;
> +}
> +
> +static IIO_CONST_ATTR(proximity_samp_freq_available,
> +				"1, 3, 5, 10, 13, 20, 83, 100");
> +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_CONST_ATTR(proximity_samp_freq_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,
> +		.info_mask = IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT,
> +	}
> +};
> +
> +static const struct iio_info isl29028_info = {
> +	.attrs =&isl29108_group,
> +	.driver_module = THIS_MODULE,
> +	.read_raw =&isl29028_read_raw,
> +	.write_raw =&isl29028_write_raw,
> +};
> +
> +static int isl29028_chip_init(struct isl29028_chip *chip)
> +{
> +	int ret;
> +
> +	chip->enable_prox  = false;
> +	chip->prox_sampling = 20;
> +	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_proxim_sampling(chip, chip->prox_sampling);
> +	if (ret<  0) {
> +		dev_err(chip->dev, "%s(): setting the proximity, err = %d\n",
> +			__func__, 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>");