[linux-2.6-block.git] / drivers / misc / isl29003.c

/*
 *  isl29003.c - Linux kernel module for
 * 	Intersil ISL29003 ambient light sensor
 *
 *  See file:Documentation/misc-devices/isl29003
 *
 *  Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
 *
 *  Based on code written by
 *  	Rodolfo Giometti <giometti@linux.it>
 *  	Eurotech S.p.A. <info@eurotech.it>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that 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, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <linux/delay.h>

#define ISL29003_DRV_NAME	"isl29003"
#define DRIVER_VERSION		"1.0"

#define ISL29003_REG_COMMAND		0x00
#define ISL29003_ADC_ENABLED		(1 << 7)
#define ISL29003_ADC_PD			(1 << 6)
#define ISL29003_TIMING_INT		(1 << 5)
#define ISL29003_MODE_SHIFT		(2)
#define ISL29003_MODE_MASK		(0x3 << ISL29003_MODE_SHIFT)
#define ISL29003_RES_SHIFT		(0)
#define ISL29003_RES_MASK		(0x3 << ISL29003_RES_SHIFT)

#define ISL29003_REG_CONTROL		0x01
#define ISL29003_INT_FLG		(1 << 5)
#define ISL29003_RANGE_SHIFT		(2)
#define ISL29003_RANGE_MASK		(0x3 << ISL29003_RANGE_SHIFT)
#define ISL29003_INT_PERSISTS_SHIFT	(0)
#define ISL29003_INT_PERSISTS_MASK	(0xf << ISL29003_INT_PERSISTS_SHIFT)

#define ISL29003_REG_IRQ_THRESH_HI	0x02
#define ISL29003_REG_IRQ_THRESH_LO	0x03
#define ISL29003_REG_LSB_SENSOR		0x04
#define ISL29003_REG_MSB_SENSOR		0x05
#define ISL29003_REG_LSB_TIMER		0x06
#define ISL29003_REG_MSB_TIMER		0x07

#define ISL29003_NUM_CACHABLE_REGS	4

struct isl29003_data {
	struct i2c_client *client;
	struct mutex lock;
	u8 reg_cache[ISL29003_NUM_CACHABLE_REGS];
	u8 power_state_before_suspend;
};

static int gain_range[] = {
	1000, 4000, 16000, 64000
};

/*
 * register access helpers
 */

static int __isl29003_read_reg(struct i2c_client *client,
			       u32 reg, u8 mask, u8 shift)
{
	struct isl29003_data *data = i2c_get_clientdata(client);

	return (data->reg_cache[reg] & mask) >> shift;
}

static int __isl29003_write_reg(struct i2c_client *client,
				u32 reg, u8 mask, u8 shift, u8 val)
{
	struct isl29003_data *data = i2c_get_clientdata(client);
	int ret = 0;
	u8 tmp;

	if (reg >= ISL29003_NUM_CACHABLE_REGS)
		return -EINVAL;

	mutex_lock(&data->lock);

	tmp = data->reg_cache[reg];
	tmp &= ~mask;
	tmp |= val << shift;

	ret = i2c_smbus_write_byte_data(client, reg, tmp);
	if (!ret)
		data->reg_cache[reg] = tmp;

	mutex_unlock(&data->lock);
	return ret;
}

/*
 * internally used functions
 */

/* range */
static int isl29003_get_range(struct i2c_client *client)
{
	return __isl29003_read_reg(client, ISL29003_REG_CONTROL,
		ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT);
}

static int isl29003_set_range(struct i2c_client *client, int range)
{
	return __isl29003_write_reg(client, ISL29003_REG_CONTROL,
		ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT, range);
}

/* resolution */
static int isl29003_get_resolution(struct i2c_client *client)
{
	return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
		ISL29003_RES_MASK, ISL29003_RES_SHIFT);
}

static int isl29003_set_resolution(struct i2c_client *client, int res)
{
	return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
		ISL29003_RES_MASK, ISL29003_RES_SHIFT, res);
}

/* mode */
static int isl29003_get_mode(struct i2c_client *client)
{
	return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
		ISL29003_RES_MASK, ISL29003_RES_SHIFT);
}

static int isl29003_set_mode(struct i2c_client *client, int mode)
{
	return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
		ISL29003_RES_MASK, ISL29003_RES_SHIFT, mode);
}

/* power_state */
static int isl29003_set_power_state(struct i2c_client *client, int state)
{
	return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
				ISL29003_ADC_ENABLED | ISL29003_ADC_PD, 0,
				state ? ISL29003_ADC_ENABLED : ISL29003_ADC_PD);
}

static int isl29003_get_power_state(struct i2c_client *client)
{
	struct isl29003_data *data = i2c_get_clientdata(client);
	u8 cmdreg = data->reg_cache[ISL29003_REG_COMMAND];

	return ~cmdreg & ISL29003_ADC_PD;
}

static int isl29003_get_adc_value(struct i2c_client *client)
{
	struct isl29003_data *data = i2c_get_clientdata(client);
	int lsb, msb, range, bitdepth;

	mutex_lock(&data->lock);
	lsb = i2c_smbus_read_byte_data(client, ISL29003_REG_LSB_SENSOR);

	if (lsb < 0) {
		mutex_unlock(&data->lock);
		return lsb;
	}

	msb = i2c_smbus_read_byte_data(client, ISL29003_REG_MSB_SENSOR);
	mutex_unlock(&data->lock);

	if (msb < 0)
		return msb;

	range = isl29003_get_range(client);
	bitdepth = (4 - isl29003_get_resolution(client)) * 4;
	return (((msb << 8) | lsb) * gain_range[range]) >> bitdepth;
}

/*
 * sysfs layer
 */

/* range */
static ssize_t isl29003_show_range(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);

	return sprintf(buf, "%i\n", isl29003_get_range(client));
}

static ssize_t isl29003_store_range(struct device *dev,
				    struct device_attribute *attr,
				    const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned long val;
	int ret;

	ret = kstrtoul(buf, 10, &val);
	if (ret)
		return ret;

	if (val > 3)
		return -EINVAL;

	ret = isl29003_set_range(client, val);
	if (ret < 0)
		return ret;

	return count;
}

static DEVICE_ATTR(range, S_IWUSR | S_IRUGO,
		   isl29003_show_range, isl29003_store_range);


/* resolution */
static ssize_t isl29003_show_resolution(struct device *dev,
					struct device_attribute *attr,
					char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);

	return sprintf(buf, "%d\n", isl29003_get_resolution(client));
}

static ssize_t isl29003_store_resolution(struct device *dev,
					 struct device_attribute *attr,
					 const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned long val;
	int ret;

	ret = kstrtoul(buf, 10, &val);
	if (ret)
		return ret;

	if (val > 3)
		return -EINVAL;

	ret = isl29003_set_resolution(client, val);
	if (ret < 0)
		return ret;

	return count;
}

static DEVICE_ATTR(resolution, S_IWUSR | S_IRUGO,
		   isl29003_show_resolution, isl29003_store_resolution);

/* mode */
static ssize_t isl29003_show_mode(struct device *dev,
				  struct device_attribute *attr, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);

	return sprintf(buf, "%d\n", isl29003_get_mode(client));
}

static ssize_t isl29003_store_mode(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned long val;
	int ret;

	ret = kstrtoul(buf, 10, &val);
	if (ret)
		return ret;

	if (val > 2)
		return -EINVAL;

	ret = isl29003_set_mode(client, val);
	if (ret < 0)
		return ret;

	return count;
}

static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO,
		   isl29003_show_mode, isl29003_store_mode);


/* power state */
static ssize_t isl29003_show_power_state(struct device *dev,
					 struct device_attribute *attr,
					 char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);

	return sprintf(buf, "%d\n", isl29003_get_power_state(client));
}

static ssize_t isl29003_store_power_state(struct device *dev,
					  struct device_attribute *attr,
					  const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned long val;
	int ret;

	ret = kstrtoul(buf, 10, &val);
	if (ret)
		return ret;

	if (val > 1)
		return -EINVAL;

	ret = isl29003_set_power_state(client, val);
	return ret ? ret : count;
}

static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
		   isl29003_show_power_state, isl29003_store_power_state);


/* lux */
static ssize_t isl29003_show_lux(struct device *dev,
				 struct device_attribute *attr, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);

	/* No LUX data if not operational */
	if (!isl29003_get_power_state(client))
		return -EBUSY;

	return sprintf(buf, "%d\n", isl29003_get_adc_value(client));
}

static DEVICE_ATTR(lux, S_IRUGO, isl29003_show_lux, NULL);

static struct attribute *isl29003_attributes[] = {
	&dev_attr_range.attr,
	&dev_attr_resolution.attr,
	&dev_attr_mode.attr,
	&dev_attr_power_state.attr,
	&dev_attr_lux.attr,
	NULL
};

static const struct attribute_group isl29003_attr_group = {
	.attrs = isl29003_attributes,
};

static int isl29003_init_client(struct i2c_client *client)
{
	struct isl29003_data *data = i2c_get_clientdata(client);
	int i;

	/* read all the registers once to fill the cache.
	 * if one of the reads fails, we consider the init failed */
	for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++) {
		int v = i2c_smbus_read_byte_data(client, i);

		if (v < 0)
			return -ENODEV;

		data->reg_cache[i] = v;
	}

	/* set defaults */
	isl29003_set_range(client, 0);
	isl29003_set_resolution(client, 0);
	isl29003_set_mode(client, 0);
	isl29003_set_power_state(client, 0);

	return 0;
}

/*
 * I2C layer
 */

static int isl29003_probe(struct i2c_client *client,
				    const struct i2c_device_id *id)
{
	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
	struct isl29003_data *data;
	int err = 0;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
		return -EIO;

	data = kzalloc(sizeof(struct isl29003_data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->client = client;
	i2c_set_clientdata(client, data);
	mutex_init(&data->lock);

	/* initialize the ISL29003 chip */
	err = isl29003_init_client(client);
	if (err)
		goto exit_kfree;

	/* register sysfs hooks */
	err = sysfs_create_group(&client->dev.kobj, &isl29003_attr_group);
	if (err)
		goto exit_kfree;

	dev_info(&client->dev, "driver version %s enabled\n", DRIVER_VERSION);
	return 0;

exit_kfree:
	kfree(data);
	return err;
}

static int isl29003_remove(struct i2c_client *client)
{
	sysfs_remove_group(&client->dev.kobj, &isl29003_attr_group);
	isl29003_set_power_state(client, 0);
	kfree(i2c_get_clientdata(client));
	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int isl29003_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct isl29003_data *data = i2c_get_clientdata(client);

	data->power_state_before_suspend = isl29003_get_power_state(client);
	return isl29003_set_power_state(client, 0);
}

static int isl29003_resume(struct device *dev)
{
	int i;
	struct i2c_client *client = to_i2c_client(dev);
	struct isl29003_data *data = i2c_get_clientdata(client);

	/* restore registers from cache */
	for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++)
		if (i2c_smbus_write_byte_data(client, i, data->reg_cache[i]))
			return -EIO;

	return isl29003_set_power_state(client,
		data->power_state_before_suspend);
}

static SIMPLE_DEV_PM_OPS(isl29003_pm_ops, isl29003_suspend, isl29003_resume);
#define ISL29003_PM_OPS (&isl29003_pm_ops)

#else
#define ISL29003_PM_OPS NULL
#endif /* CONFIG_PM_SLEEP */

static const struct i2c_device_id isl29003_id[] = {
	{ "isl29003", 0 },
	{}
};
MODULE_DEVICE_TABLE(i2c, isl29003_id);

static struct i2c_driver isl29003_driver = {
	.driver = {
		.name	= ISL29003_DRV_NAME,
		.pm	= ISL29003_PM_OPS,
	},
	.probe	= isl29003_probe,
	.remove	= isl29003_remove,
	.id_table = isl29003_id,
};

module_i2c_driver(isl29003_driver);

MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
MODULE_DESCRIPTION("ISL29003 ambient light sensor driver");
MODULE_LICENSE("GPL v2");
MODULE_VERSION(DRIVER_VERSION);
Commit	Line	Data
3cdbbeeb DM	1	/*
	2	* isl29003.c - Linux kernel module for
	3	* Intersil ISL29003 ambient light sensor
	4	*
	5	* See file:Documentation/misc-devices/isl29003
	6	*
	7	* Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
	8	*
	9	* Based on code written by
	10	* Rodolfo Giometti <giometti@linux.it>
	11	* Eurotech S.p.A. <info@eurotech.it>
	12	*
	13	* This program is free software; you can redistribute it and/or modify
	14	* it under the terms of the GNU General Public License as published by
	15	* the Free Software Foundation; either version 2 of the License, or
	16	* (at your option) any later version.
	17	*
	18	* This program is distributed in the hope that it will be useful,
	19	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	20	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	21	* GNU General Public License for more details.
	22	*
	23	* You should have received a copy of the GNU General Public License
	24	* along with this program; if not, write to the Free Software
	25	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	26	*/
	27
	28	#include <linux/module.h>
3cdbbeeb DM	29	#include <linux/slab.h>
	30	#include <linux/i2c.h>
	31	#include <linux/mutex.h>
	32	#include <linux/delay.h>
	33
	34	#define ISL29003_DRV_NAME "isl29003"
	35	#define DRIVER_VERSION "1.0"
	36
	37	#define ISL29003_REG_COMMAND 0x00
	38	#define ISL29003_ADC_ENABLED (1 << 7)
	39	#define ISL29003_ADC_PD (1 << 6)
	40	#define ISL29003_TIMING_INT (1 << 5)
	41	#define ISL29003_MODE_SHIFT (2)
	42	#define ISL29003_MODE_MASK (0x3 << ISL29003_MODE_SHIFT)
	43	#define ISL29003_RES_SHIFT (0)
	44	#define ISL29003_RES_MASK (0x3 << ISL29003_RES_SHIFT)
	45
	46	#define ISL29003_REG_CONTROL 0x01
	47	#define ISL29003_INT_FLG (1 << 5)
	48	#define ISL29003_RANGE_SHIFT (2)
	49	#define ISL29003_RANGE_MASK (0x3 << ISL29003_RANGE_SHIFT)
	50	#define ISL29003_INT_PERSISTS_SHIFT (0)
	51	#define ISL29003_INT_PERSISTS_MASK (0xf << ISL29003_INT_PERSISTS_SHIFT)
	52
	53	#define ISL29003_REG_IRQ_THRESH_HI 0x02
	54	#define ISL29003_REG_IRQ_THRESH_LO 0x03
	55	#define ISL29003_REG_LSB_SENSOR 0x04
	56	#define ISL29003_REG_MSB_SENSOR 0x05
	57	#define ISL29003_REG_LSB_TIMER 0x06
	58	#define ISL29003_REG_MSB_TIMER 0x07
	59
	60	#define ISL29003_NUM_CACHABLE_REGS 4
	61
	62	struct isl29003_data {
	63	struct i2c_client *client;
	64	struct mutex lock;
	65	u8 reg_cache[ISL29003_NUM_CACHABLE_REGS];
74614f8d	66	u8 power_state_before_suspend;
3cdbbeeb DM	67	};
	68
	69	static int gain_range[] = {
	70	1000, 4000, 16000, 64000
	71	};
	72
	73	/*
	74	* register access helpers
	75	*/
	76
	77	static int __isl29003_read_reg(struct i2c_client *client,
	78	u32 reg, u8 mask, u8 shift)
	79	{
	80	struct isl29003_data *data = i2c_get_clientdata(client);
05eec0c9	81
3cdbbeeb DM	82	return (data->reg_cache[reg] & mask) >> shift;
	83	}
	84
	85	static int __isl29003_write_reg(struct i2c_client *client,
	86	u32 reg, u8 mask, u8 shift, u8 val)
	87	{
	88	struct isl29003_data *data = i2c_get_clientdata(client);
	89	int ret = 0;
	90	u8 tmp;
	91
	92	if (reg >= ISL29003_NUM_CACHABLE_REGS)
	93	return -EINVAL;
	94
	95	mutex_lock(&data->lock);
	96
	97	tmp = data->reg_cache[reg];
	98	tmp &= ~mask;
	99	tmp \|= val << shift;
	100
	101	ret = i2c_smbus_write_byte_data(client, reg, tmp);
	102	if (!ret)
	103	data->reg_cache[reg] = tmp;
	104
	105	mutex_unlock(&data->lock);
	106	return ret;
	107	}
	108
	109	/*
	110	* internally used functions
	111	*/
	112
	113	/* range */
	114	static int isl29003_get_range(struct i2c_client *client)
	115	{
	116	return __isl29003_read_reg(client, ISL29003_REG_CONTROL,
	117	ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT);
	118	}
	119
	120	static int isl29003_set_range(struct i2c_client *client, int range)
	121	{
	122	return __isl29003_write_reg(client, ISL29003_REG_CONTROL,
	123	ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT, range);
	124	}
	125
	126	/* resolution */
	127	static int isl29003_get_resolution(struct i2c_client *client)
	128	{
	129	return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
	130	ISL29003_RES_MASK, ISL29003_RES_SHIFT);
	131	}
	132
	133	static int isl29003_set_resolution(struct i2c_client *client, int res)
	134	{
	135	return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
	136	ISL29003_RES_MASK, ISL29003_RES_SHIFT, res);
	137	}
	138
	139	/* mode */
	140	static int isl29003_get_mode(struct i2c_client *client)
	141	{
	142	return __isl29003_read_reg(client, ISL29003_REG_COMMAND,
	143	ISL29003_RES_MASK, ISL29003_RES_SHIFT);
	144	}
	145
146	static int isl29003_set_mode(struct i2c_client *client, int mode)
147	{
148	return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
149	ISL29003_RES_MASK, ISL29003_RES_SHIFT, mode);
150	}
151
152	/* power_state */
153	static int isl29003_set_power_state(struct i2c_client *client, int state)
154	{
155	return __isl29003_write_reg(client, ISL29003_REG_COMMAND,
156	ISL29003_ADC_ENABLED \| ISL29003_ADC_PD, 0,
157	state ? ISL29003_ADC_ENABLED : ISL29003_ADC_PD);
158	}
159
160	static int isl29003_get_power_state(struct i2c_client *client)
161	{
162	struct isl29003_data *data = i2c_get_clientdata(client);
163	u8 cmdreg = data->reg_cache[ISL29003_REG_COMMAND];
05eec0c9	164
3cdbbeeb DM	165	return ~cmdreg & ISL29003_ADC_PD;
	166	}
	167
	168	static int isl29003_get_adc_value(struct i2c_client *client)
	169	{
	170	struct isl29003_data *data = i2c_get_clientdata(client);
	171	int lsb, msb, range, bitdepth;
	172
	173	mutex_lock(&data->lock);
	174	lsb = i2c_smbus_read_byte_data(client, ISL29003_REG_LSB_SENSOR);
	175
	176	if (lsb < 0) {
	177	mutex_unlock(&data->lock);
	178	return lsb;
	179	}
	180
	181	msb = i2c_smbus_read_byte_data(client, ISL29003_REG_MSB_SENSOR);
	182	mutex_unlock(&data->lock);
	183
	184	if (msb < 0)
	185	return msb;
	186
	187	range = isl29003_get_range(client);
	188	bitdepth = (4 - isl29003_get_resolution(client)) * 4;
	189	return (((msb << 8) \| lsb) * gain_range[range]) >> bitdepth;
	190	}
	191
	192	/*
	193	* sysfs layer
	194	*/
	195
	196	/* range */
	197	static ssize_t isl29003_show_range(struct device *dev,
	198	struct device_attribute attr, char buf)
	199	{
	200	struct i2c_client *client = to_i2c_client(dev);
05eec0c9	201
3cdbbeeb DM	202	return sprintf(buf, "%i\n", isl29003_get_range(client));
	203	}
	204
	205	static ssize_t isl29003_store_range(struct device *dev,
	206	struct device_attribute *attr,
	207	const char *buf, size_t count)
	208	{
	209	struct i2c_client *client = to_i2c_client(dev);
	210	unsigned long val;
	211	int ret;
	212
f7b41276 JH	213	ret = kstrtoul(buf, 10, &val);
	214	if (ret)
	215	return ret;
	216
	217	if (val > 3)
3cdbbeeb DM	218	return -EINVAL;
	219
	220	ret = isl29003_set_range(client, val);
	221	if (ret < 0)
	222	return ret;
	223
	224	return count;
	225	}
	226
	227	static DEVICE_ATTR(range, S_IWUSR \| S_IRUGO,
	228	isl29003_show_range, isl29003_store_range);
	229
	230
	231	/* resolution */
	232	static ssize_t isl29003_show_resolution(struct device *dev,
	233	struct device_attribute *attr,
	234	char *buf)
	235	{
	236	struct i2c_client *client = to_i2c_client(dev);
05eec0c9	237
3cdbbeeb DM	238	return sprintf(buf, "%d\n", isl29003_get_resolution(client));
	239	}
	240
	241	static ssize_t isl29003_store_resolution(struct device *dev,
	242	struct device_attribute *attr,
	243	const char *buf, size_t count)
	244	{
	245	struct i2c_client *client = to_i2c_client(dev);
	246	unsigned long val;
	247	int ret;
	248
f7b41276 JH	249	ret = kstrtoul(buf, 10, &val);
	250	if (ret)
	251	return ret;
	252
	253	if (val > 3)
3cdbbeeb DM	254	return -EINVAL;
	255
	256	ret = isl29003_set_resolution(client, val);
	257	if (ret < 0)
	258	return ret;
	259
	260	return count;
	261	}
	262
	263	static DEVICE_ATTR(resolution, S_IWUSR \| S_IRUGO,
	264	isl29003_show_resolution, isl29003_store_resolution);
	265
	266	/* mode */
	267	static ssize_t isl29003_show_mode(struct device *dev,
	268	struct device_attribute attr, char buf)
	269	{
	270	struct i2c_client *client = to_i2c_client(dev);
05eec0c9	271
3cdbbeeb DM	272	return sprintf(buf, "%d\n", isl29003_get_mode(client));
	273	}
	274
	275	static ssize_t isl29003_store_mode(struct device *dev,
	276	struct device_attribute attr, const char buf, size_t count)
	277	{
	278	struct i2c_client *client = to_i2c_client(dev);
	279	unsigned long val;
	280	int ret;
	281
f7b41276 JH	282	ret = kstrtoul(buf, 10, &val);
	283	if (ret)
	284	return ret;
	285
	286	if (val > 2)
3cdbbeeb DM	287	return -EINVAL;
	288
	289	ret = isl29003_set_mode(client, val);
	290	if (ret < 0)
	291	return ret;
	292
	293	return count;
	294	}
	295
	296	static DEVICE_ATTR(mode, S_IWUSR \| S_IRUGO,
	297	isl29003_show_mode, isl29003_store_mode);
	298
	299
	300	/* power state */
	301	static ssize_t isl29003_show_power_state(struct device *dev,
	302	struct device_attribute *attr,
	303	char *buf)
	304	{
	305	struct i2c_client *client = to_i2c_client(dev);
05eec0c9	306
3cdbbeeb DM	307	return sprintf(buf, "%d\n", isl29003_get_power_state(client));
	308	}
	309
	310	static ssize_t isl29003_store_power_state(struct device *dev,
	311	struct device_attribute *attr,
	312	const char *buf, size_t count)
	313	{
	314	struct i2c_client *client = to_i2c_client(dev);
	315	unsigned long val;
	316	int ret;
	317
f7b41276 JH	318	ret = kstrtoul(buf, 10, &val);
	319	if (ret)
	320	return ret;
	321
	322	if (val > 1)
3cdbbeeb DM	323	return -EINVAL;
	324
	325	ret = isl29003_set_power_state(client, val);
	326	return ret ? ret : count;
	327	}
	328
	329	static DEVICE_ATTR(power_state, S_IWUSR \| S_IRUGO,
	330	isl29003_show_power_state, isl29003_store_power_state);
	331
	332
	333	/* lux */
	334	static ssize_t isl29003_show_lux(struct device *dev,
	335	struct device_attribute attr, char buf)
	336	{
	337	struct i2c_client *client = to_i2c_client(dev);
	338
	339	/* No LUX data if not operational */
	340	if (!isl29003_get_power_state(client))
	341	return -EBUSY;
	342
	343	return sprintf(buf, "%d\n", isl29003_get_adc_value(client));
	344	}
	345
	346	static DEVICE_ATTR(lux, S_IRUGO, isl29003_show_lux, NULL);
	347
	348	static struct attribute *isl29003_attributes[] = {
	349	&dev_attr_range.attr,
	350	&dev_attr_resolution.attr,
	351	&dev_attr_mode.attr,
	352	&dev_attr_power_state.attr,
	353	&dev_attr_lux.attr,
	354	NULL
	355	};
	356
	357	static const struct attribute_group isl29003_attr_group = {
	358	.attrs = isl29003_attributes,
	359	};
	360
	361	static int isl29003_init_client(struct i2c_client *client)
	362	{
	363	struct isl29003_data *data = i2c_get_clientdata(client);
	364	int i;
	365
	366	/* read all the registers once to fill the cache.
	367	* if one of the reads fails, we consider the init failed */
	368	for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++) {
	369	int v = i2c_smbus_read_byte_data(client, i);
05eec0c9	370
3cdbbeeb DM	371	if (v < 0)
	372	return -ENODEV;
	373
	374	data->reg_cache[i] = v;
	375	}
	376
	377	/* set defaults */
	378	isl29003_set_range(client, 0);
	379	isl29003_set_resolution(client, 0);
	380	isl29003_set_mode(client, 0);
	381	isl29003_set_power_state(client, 0);
	382
	383	return 0;
	384	}
	385
	386	/*
	387	* I2C layer
	388	*/
	389
80c8ae28	390	static int isl29003_probe(struct i2c_client *client,
3cdbbeeb DM	391	const struct i2c_device_id *id)
	392	{
	393	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
	394	struct isl29003_data *data;
	395	int err = 0;
	396
	397	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
	398	return -EIO;
	399
	400	data = kzalloc(sizeof(struct isl29003_data), GFP_KERNEL);
	401	if (!data)
	402	return -ENOMEM;
	403
	404	data->client = client;
	405	i2c_set_clientdata(client, data);
	406	mutex_init(&data->lock);
	407
	408	/* initialize the ISL29003 chip */
	409	err = isl29003_init_client(client);
	410	if (err)
	411	goto exit_kfree;
	412
	413	/* register sysfs hooks */
	414	err = sysfs_create_group(&client->dev.kobj, &isl29003_attr_group);
	415	if (err)
	416	goto exit_kfree;
	417
	418	dev_info(&client->dev, "driver version %s enabled\n", DRIVER_VERSION);
	419	return 0;
	420
	421	exit_kfree:
	422	kfree(data);
	423	return err;
	424	}
	425
486a5c28	426	static int isl29003_remove(struct i2c_client *client)
3cdbbeeb DM	427	{
	428	sysfs_remove_group(&client->dev.kobj, &isl29003_attr_group);
	429	isl29003_set_power_state(client, 0);
	430	kfree(i2c_get_clientdata(client));
	431	return 0;
	432	}
	433
873bf4f4 LPC	434	#ifdef CONFIG_PM_SLEEP
873bf4f4 LPC	435	static int isl29003_suspend(struct device *dev)
3cdbbeeb	436	{
873bf4f4	437	struct i2c_client *client = to_i2c_client(dev);
74614f8d DM	438	struct isl29003_data *data = i2c_get_clientdata(client);
	439
	440	data->power_state_before_suspend = isl29003_get_power_state(client);
3cdbbeeb DM	441	return isl29003_set_power_state(client, 0);
	442	}
	443
873bf4f4	444	static int isl29003_resume(struct device *dev)
3cdbbeeb DM	445	{
3cdbbeeb DM	446	int i;
873bf4f4	447	struct i2c_client *client = to_i2c_client(dev);
3cdbbeeb DM	448	struct isl29003_data *data = i2c_get_clientdata(client);
	449
	450	/* restore registers from cache */
	451	for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++)
74614f8d	452	if (i2c_smbus_write_byte_data(client, i, data->reg_cache[i]))
3cdbbeeb DM	453	return -EIO;
3cdbbeeb DM	454
74614f8d DM	455	return isl29003_set_power_state(client,
74614f8d DM	456	data->power_state_before_suspend);
3cdbbeeb DM	457	}
3cdbbeeb DM	458
873bf4f4 LPC	459	static SIMPLE_DEV_PM_OPS(isl29003_pm_ops, isl29003_suspend, isl29003_resume);
	460	#define ISL29003_PM_OPS (&isl29003_pm_ops)
	461
3cdbbeeb	462	#else
873bf4f4 LPC	463	#define ISL29003_PM_OPS NULL
873bf4f4 LPC	464	#endif /* CONFIG_PM_SLEEP */
3cdbbeeb DM	465
	466	static const struct i2c_device_id isl29003_id[] = {
	467	{ "isl29003", 0 },
	468	{}
	469	};
	470	MODULE_DEVICE_TABLE(i2c, isl29003_id);
	471
	472	static struct i2c_driver isl29003_driver = {
	473	.driver = {
	474	.name = ISL29003_DRV_NAME,
873bf4f4	475	.pm = ISL29003_PM_OPS,
3cdbbeeb	476	},
3cdbbeeb	477	.probe = isl29003_probe,
2d6bed9c	478	.remove = isl29003_remove,
3cdbbeeb DM	479	.id_table = isl29003_id,
	480	};
	481
a64fe2ed	482	module_i2c_driver(isl29003_driver);
3cdbbeeb DM	483
	484	MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
	485	MODULE_DESCRIPTION("ISL29003 ambient light sensor driver");
	486	MODULE_LICENSE("GPL v2");
	487	MODULE_VERSION(DRIVER_VERSION);