[net-next-2.6.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/init.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;

	if ((strict_strtoul(buf, 10, &val) < 0) || (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;

	if ((strict_strtoul(buf, 10, &val) < 0) || (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;

	if ((strict_strtoul(buf, 10, &val) < 0) || (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;

	if ((strict_strtoul(buf, 10, &val) < 0) || (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 __devinit 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 __devexit 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
static int isl29003_suspend(struct i2c_client *client, pm_message_t mesg)
{
	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 i2c_client *client)
{
	int i;
	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);
}

#else
#define isl29003_suspend	NULL
#define isl29003_resume		NULL
#endif /* CONFIG_PM */

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,
		.owner	= THIS_MODULE,
	},
	.suspend = isl29003_suspend,
	.resume	= isl29003_resume,
	.probe	= isl29003_probe,
	.remove	= __devexit_p(isl29003_remove),
	.id_table = isl29003_id,
};

static int __init isl29003_init(void)
{
	return i2c_add_driver(&isl29003_driver);
}

static void __exit isl29003_exit(void)
{
	i2c_del_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);

module_init(isl29003_init);
module_exit(isl29003_exit);
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>
	29	#include <linux/init.h>
	30	#include <linux/slab.h>
	31	#include <linux/i2c.h>
	32	#include <linux/mutex.h>
	33	#include <linux/delay.h>
	34
	35	#define ISL29003_DRV_NAME "isl29003"
	36	#define DRIVER_VERSION "1.0"
	37
	38	#define ISL29003_REG_COMMAND 0x00
	39	#define ISL29003_ADC_ENABLED (1 << 7)
	40	#define ISL29003_ADC_PD (1 << 6)
	41	#define ISL29003_TIMING_INT (1 << 5)
	42	#define ISL29003_MODE_SHIFT (2)
	43	#define ISL29003_MODE_MASK (0x3 << ISL29003_MODE_SHIFT)
	44	#define ISL29003_RES_SHIFT (0)
	45	#define ISL29003_RES_MASK (0x3 << ISL29003_RES_SHIFT)
	46
	47	#define ISL29003_REG_CONTROL 0x01
	48	#define ISL29003_INT_FLG (1 << 5)
	49	#define ISL29003_RANGE_SHIFT (2)
	50	#define ISL29003_RANGE_MASK (0x3 << ISL29003_RANGE_SHIFT)
	51	#define ISL29003_INT_PERSISTS_SHIFT (0)
	52	#define ISL29003_INT_PERSISTS_MASK (0xf << ISL29003_INT_PERSISTS_SHIFT)
	53
	54	#define ISL29003_REG_IRQ_THRESH_HI 0x02
	55	#define ISL29003_REG_IRQ_THRESH_LO 0x03
	56	#define ISL29003_REG_LSB_SENSOR 0x04
	57	#define ISL29003_REG_MSB_SENSOR 0x05
	58	#define ISL29003_REG_LSB_TIMER 0x06
	59	#define ISL29003_REG_MSB_TIMER 0x07
	60
	61	#define ISL29003_NUM_CACHABLE_REGS 4
	62
	63	struct isl29003_data {
	64	struct i2c_client *client;
65	struct mutex lock;
66	u8 reg_cache[ISL29003_NUM_CACHABLE_REGS];
74614f8d	67	u8 power_state_before_suspend;
3cdbbeeb DM	68	};
	69
	70	static int gain_range[] = {
	71	1000, 4000, 16000, 64000
	72	};
	73
	74	/*
	75	* register access helpers
	76	*/
	77
	78	static int __isl29003_read_reg(struct i2c_client *client,
	79	u32 reg, u8 mask, u8 shift)
	80	{
	81	struct isl29003_data *data = i2c_get_clientdata(client);
	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];
164	return ~cmdreg & ISL29003_ADC_PD;
165	}
166
167	static int isl29003_get_adc_value(struct i2c_client *client)
168	{
169	struct isl29003_data *data = i2c_get_clientdata(client);
170	int lsb, msb, range, bitdepth;
171
172	mutex_lock(&data->lock);
173	lsb = i2c_smbus_read_byte_data(client, ISL29003_REG_LSB_SENSOR);
174
175	if (lsb < 0) {
176	mutex_unlock(&data->lock);
177	return lsb;
178	}
179
180	msb = i2c_smbus_read_byte_data(client, ISL29003_REG_MSB_SENSOR);
181	mutex_unlock(&data->lock);
182
183	if (msb < 0)
184	return msb;
185
186	range = isl29003_get_range(client);
187	bitdepth = (4 - isl29003_get_resolution(client)) * 4;
188	return (((msb << 8) \| lsb) * gain_range[range]) >> bitdepth;
189	}
190
191	/*
192	* sysfs layer
193	*/
194
195	/* range */
196	static ssize_t isl29003_show_range(struct device *dev,
197	struct device_attribute attr, char buf)
198	{
199	struct i2c_client *client = to_i2c_client(dev);
200	return sprintf(buf, "%i\n", isl29003_get_range(client));
201	}
202
203	static ssize_t isl29003_store_range(struct device *dev,
204	struct device_attribute *attr,
205	const char *buf, size_t count)
206	{
207	struct i2c_client *client = to_i2c_client(dev);
208	unsigned long val;
209	int ret;
210
211	if ((strict_strtoul(buf, 10, &val) < 0) \|\| (val > 3))
212	return -EINVAL;
213
214	ret = isl29003_set_range(client, val);
215	if (ret < 0)
216	return ret;
217
218	return count;
219	}
220
221	static DEVICE_ATTR(range, S_IWUSR \| S_IRUGO,
222	isl29003_show_range, isl29003_store_range);
223
224
225	/* resolution */
226	static ssize_t isl29003_show_resolution(struct device *dev,
227	struct device_attribute *attr,
228	char *buf)
229	{
230	struct i2c_client *client = to_i2c_client(dev);
231	return sprintf(buf, "%d\n", isl29003_get_resolution(client));
232	}
233
234	static ssize_t isl29003_store_resolution(struct device *dev,
235	struct device_attribute *attr,
236	const char *buf, size_t count)
237	{
238	struct i2c_client *client = to_i2c_client(dev);
239	unsigned long val;
240	int ret;
241
242	if ((strict_strtoul(buf, 10, &val) < 0) \|\| (val > 3))
243	return -EINVAL;
244
245	ret = isl29003_set_resolution(client, val);
246	if (ret < 0)
247	return ret;
248
249	return count;
250	}
251
252	static DEVICE_ATTR(resolution, S_IWUSR \| S_IRUGO,
253	isl29003_show_resolution, isl29003_store_resolution);
254
255	/* mode */
256	static ssize_t isl29003_show_mode(struct device *dev,
257	struct device_attribute attr, char buf)
258	{
259	struct i2c_client *client = to_i2c_client(dev);
260	return sprintf(buf, "%d\n", isl29003_get_mode(client));
261	}
262
263	static ssize_t isl29003_store_mode(struct device *dev,
264	struct device_attribute attr, const char buf, size_t count)
265	{
266	struct i2c_client *client = to_i2c_client(dev);
267	unsigned long val;
268	int ret;
269
270	if ((strict_strtoul(buf, 10, &val) < 0) \|\| (val > 2))
271	return -EINVAL;
272
273	ret = isl29003_set_mode(client, val);
274	if (ret < 0)
275	return ret;
276
277	return count;
278	}
279
280	static DEVICE_ATTR(mode, S_IWUSR \| S_IRUGO,
281	isl29003_show_mode, isl29003_store_mode);
282
283
284	/* power state */
285	static ssize_t isl29003_show_power_state(struct device *dev,
286	struct device_attribute *attr,
287	char *buf)
288	{
289	struct i2c_client *client = to_i2c_client(dev);
290	return sprintf(buf, "%d\n", isl29003_get_power_state(client));
291	}
292
293	static ssize_t isl29003_store_power_state(struct device *dev,
294	struct device_attribute *attr,
295	const char *buf, size_t count)
296	{
297	struct i2c_client *client = to_i2c_client(dev);
298	unsigned long val;
299	int ret;
300
301	if ((strict_strtoul(buf, 10, &val) < 0) \|\| (val > 1))
302	return -EINVAL;
303
304	ret = isl29003_set_power_state(client, val);
305	return ret ? ret : count;
306	}
307
308	static DEVICE_ATTR(power_state, S_IWUSR \| S_IRUGO,
309	isl29003_show_power_state, isl29003_store_power_state);
310
311
312	/* lux */
313	static ssize_t isl29003_show_lux(struct device *dev,
314	struct device_attribute attr, char buf)
315	{
316	struct i2c_client *client = to_i2c_client(dev);
317
318	/* No LUX data if not operational */
319	if (!isl29003_get_power_state(client))
320	return -EBUSY;
321
322	return sprintf(buf, "%d\n", isl29003_get_adc_value(client));
323	}
324
325	static DEVICE_ATTR(lux, S_IRUGO, isl29003_show_lux, NULL);
326
327	static struct attribute *isl29003_attributes[] = {
328	&dev_attr_range.attr,
329	&dev_attr_resolution.attr,
330	&dev_attr_mode.attr,
331	&dev_attr_power_state.attr,
332	&dev_attr_lux.attr,
333	NULL
334	};
335
336	static const struct attribute_group isl29003_attr_group = {
337	.attrs = isl29003_attributes,
338	};
339
340	static int isl29003_init_client(struct i2c_client *client)
341	{
342	struct isl29003_data *data = i2c_get_clientdata(client);
343	int i;
344
345	/* read all the registers once to fill the cache.
346	* if one of the reads fails, we consider the init failed */
347	for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++) {
348	int v = i2c_smbus_read_byte_data(client, i);
349	if (v < 0)
350	return -ENODEV;
351
352	data->reg_cache[i] = v;
353	}
354
355	/* set defaults */
356	isl29003_set_range(client, 0);
357	isl29003_set_resolution(client, 0);
358	isl29003_set_mode(client, 0);
359	isl29003_set_power_state(client, 0);
360
361	return 0;
362	}
363
364	/*
365	* I2C layer
366	*/
367
368	static int __devinit isl29003_probe(struct i2c_client *client,
369	const struct i2c_device_id *id)
370	{
371	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
372	struct isl29003_data *data;
373	int err = 0;
374
375	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
376	return -EIO;
377
378	data = kzalloc(sizeof(struct isl29003_data), GFP_KERNEL);
379	if (!data)
380	return -ENOMEM;
381
382	data->client = client;
383	i2c_set_clientdata(client, data);
384	mutex_init(&data->lock);
385
386	/* initialize the ISL29003 chip */
387	err = isl29003_init_client(client);
388	if (err)
389	goto exit_kfree;
390
391	/* register sysfs hooks */
392	err = sysfs_create_group(&client->dev.kobj, &isl29003_attr_group);
393	if (err)
394	goto exit_kfree;
395
396	dev_info(&client->dev, "driver version %s enabled\n", DRIVER_VERSION);
397	return 0;
398
399	exit_kfree:
400	kfree(data);
401	return err;
402	}
403
404	static int __devexit isl29003_remove(struct i2c_client *client)
405	{
406	sysfs_remove_group(&client->dev.kobj, &isl29003_attr_group);
407	isl29003_set_power_state(client, 0);
408	kfree(i2c_get_clientdata(client));
409	return 0;
410	}
411
412	#ifdef CONFIG_PM
413	static int isl29003_suspend(struct i2c_client *client, pm_message_t mesg)
414	{
74614f8d DM	415	struct isl29003_data *data = i2c_get_clientdata(client);
	416
	417	data->power_state_before_suspend = isl29003_get_power_state(client);
3cdbbeeb DM	418	return isl29003_set_power_state(client, 0);
	419	}
	420
	421	static int isl29003_resume(struct i2c_client *client)
	422	{
	423	int i;
	424	struct isl29003_data *data = i2c_get_clientdata(client);
	425
	426	/* restore registers from cache */
	427	for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++)
74614f8d	428	if (i2c_smbus_write_byte_data(client, i, data->reg_cache[i]))
3cdbbeeb DM	429	return -EIO;
3cdbbeeb DM	430
74614f8d DM	431	return isl29003_set_power_state(client,
74614f8d DM	432	data->power_state_before_suspend);
3cdbbeeb DM	433	}
	434
	435	#else
	436	#define isl29003_suspend NULL
	437	#define isl29003_resume NULL
	438	#endif /* CONFIG_PM */
	439
	440	static const struct i2c_device_id isl29003_id[] = {
	441	{ "isl29003", 0 },
	442	{}
	443	};
	444	MODULE_DEVICE_TABLE(i2c, isl29003_id);
	445
	446	static struct i2c_driver isl29003_driver = {
	447	.driver = {
	448	.name = ISL29003_DRV_NAME,
	449	.owner = THIS_MODULE,
	450	},
	451	.suspend = isl29003_suspend,
	452	.resume = isl29003_resume,
	453	.probe = isl29003_probe,
	454	.remove = __devexit_p(isl29003_remove),
	455	.id_table = isl29003_id,
	456	};
	457
	458	static int __init isl29003_init(void)
	459	{
	460	return i2c_add_driver(&isl29003_driver);
	461	}
	462
	463	static void __exit isl29003_exit(void)
	464	{
	465	i2c_del_driver(&isl29003_driver);
	466	}
	467
	468	MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
	469	MODULE_DESCRIPTION("ISL29003 ambient light sensor driver");
	470	MODULE_LICENSE("GPL v2");
	471	MODULE_VERSION(DRIVER_VERSION);
	472
	473	module_init(isl29003_init);
	474	module_exit(isl29003_exit);
	475