[linux.git] / drivers / misc / bh1780gli.c

/*
 * bh1780gli.c
 * ROHM Ambient Light Sensor Driver
 *
 * Copyright (C) 2010 Texas Instruments
 * Author: Hemanth V <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/module.h>

#define BH1780_REG_CONTROL	0x80
#define BH1780_REG_PARTID	0x8A
#define BH1780_REG_MANFID	0x8B
#define BH1780_REG_DLOW	0x8C
#define BH1780_REG_DHIGH	0x8D

#define BH1780_REVMASK		(0xf)
#define BH1780_POWMASK		(0x3)
#define BH1780_POFF		(0x0)
#define BH1780_PON		(0x3)

/* power on settling time in ms */
#define BH1780_PON_DELAY	2

struct bh1780_data {
	struct i2c_client *client;
	int power_state;
	/* lock for sysfs operations */
	struct mutex lock;
};

static int bh1780_write(struct bh1780_data *ddata, u8 reg, u8 val, char *msg)
{
	int ret = i2c_smbus_write_byte_data(ddata->client, reg, val);
	if (ret < 0)
		dev_err(&ddata->client->dev,
			"i2c_smbus_write_byte_data failed error %d Register (%s)\n",
			ret, msg);
	return ret;
}

static int bh1780_read(struct bh1780_data *ddata, u8 reg, char *msg)
{
	int ret = i2c_smbus_read_byte_data(ddata->client, reg);
	if (ret < 0)
		dev_err(&ddata->client->dev,
			"i2c_smbus_read_byte_data failed error %d Register (%s)\n",
			ret, msg);
	return ret;
}

static ssize_t bh1780_show_lux(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct bh1780_data *ddata = platform_get_drvdata(pdev);
	int lsb, msb;

	lsb = bh1780_read(ddata, BH1780_REG_DLOW, "DLOW");
	if (lsb < 0)
		return lsb;

	msb = bh1780_read(ddata, BH1780_REG_DHIGH, "DHIGH");
	if (msb < 0)
		return msb;

	return sprintf(buf, "%d\n", (msb << 8) | lsb);
}

static ssize_t bh1780_show_power_state(struct device *dev,
					struct device_attribute *attr,
					char *buf)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct bh1780_data *ddata = platform_get_drvdata(pdev);
	int state;

	state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL");
	if (state < 0)
		return state;

	return sprintf(buf, "%d\n", state & BH1780_POWMASK);
}

static ssize_t bh1780_store_power_state(struct device *dev,
					struct device_attribute *attr,
					const char *buf, size_t count)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct bh1780_data *ddata = platform_get_drvdata(pdev);
	unsigned long val;
	int error;

	error = strict_strtoul(buf, 0, &val);
	if (error)
		return error;

	if (val < BH1780_POFF || val > BH1780_PON)
		return -EINVAL;

	mutex_lock(&ddata->lock);

	error = bh1780_write(ddata, BH1780_REG_CONTROL, val, "CONTROL");
	if (error < 0) {
		mutex_unlock(&ddata->lock);
		return error;
	}

	msleep(BH1780_PON_DELAY);
	ddata->power_state = val;
	mutex_unlock(&ddata->lock);

	return count;
}

static DEVICE_ATTR(lux, S_IRUGO, bh1780_show_lux, NULL);

static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
		bh1780_show_power_state, bh1780_store_power_state);

static struct attribute *bh1780_attributes[] = {
	&dev_attr_power_state.attr,
	&dev_attr_lux.attr,
	NULL
};

static const struct attribute_group bh1780_attr_group = {
	.attrs = bh1780_attributes,
};

static int bh1780_probe(struct i2c_client *client,
						const struct i2c_device_id *id)
{
	int ret;
	struct bh1780_data *ddata = NULL;
	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) {
		ret = -EIO;
		goto err_op_failed;
	}

	ddata = kzalloc(sizeof(struct bh1780_data), GFP_KERNEL);
	if (ddata == NULL) {
		ret = -ENOMEM;
		goto err_op_failed;
	}

	ddata->client = client;
	i2c_set_clientdata(client, ddata);

	ret = bh1780_read(ddata, BH1780_REG_PARTID, "PART ID");
	if (ret < 0)
		goto err_op_failed;

	dev_info(&client->dev, "Ambient Light Sensor, Rev : %d\n",
			(ret & BH1780_REVMASK));

	mutex_init(&ddata->lock);

	ret = sysfs_create_group(&client->dev.kobj, &bh1780_attr_group);
	if (ret)
		goto err_op_failed;

	return 0;

err_op_failed:
	kfree(ddata);
	return ret;
}

static int bh1780_remove(struct i2c_client *client)
{
	struct bh1780_data *ddata;

	ddata = i2c_get_clientdata(client);
	sysfs_remove_group(&client->dev.kobj, &bh1780_attr_group);
	kfree(ddata);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int bh1780_suspend(struct device *dev)
{
	struct bh1780_data *ddata;
	int state, ret;
	struct i2c_client *client = to_i2c_client(dev);

	ddata = i2c_get_clientdata(client);
	state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL");
	if (state < 0)
		return state;

	ddata->power_state = state & BH1780_POWMASK;

	ret = bh1780_write(ddata, BH1780_REG_CONTROL, BH1780_POFF,
				"CONTROL");

	if (ret < 0)
		return ret;

	return 0;
}

static int bh1780_resume(struct device *dev)
{
	struct bh1780_data *ddata;
	int state, ret;
	struct i2c_client *client = to_i2c_client(dev);

	ddata = i2c_get_clientdata(client);
	state = ddata->power_state;
	ret = bh1780_write(ddata, BH1780_REG_CONTROL, state,
				"CONTROL");

	if (ret < 0)
		return ret;

	return 0;
}
#endif /* CONFIG_PM_SLEEP */

static SIMPLE_DEV_PM_OPS(bh1780_pm, bh1780_suspend, bh1780_resume);

static const struct i2c_device_id bh1780_id[] = {
	{ "bh1780", 0 },
	{ },
};

static struct i2c_driver bh1780_driver = {
	.probe		= bh1780_probe,
	.remove		= bh1780_remove,
	.id_table	= bh1780_id,
	.driver = {
		.name = "bh1780",
		.pm	= &bh1780_pm,
	},
};

module_i2c_driver(bh1780_driver);

MODULE_DESCRIPTION("BH1780GLI Ambient Light Sensor Driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Hemanth V <[email protected]>");
Commit	Line	Data
7efe15f2 H	1	/*
	2	* bh1780gli.c
	3	* ROHM Ambient Light Sensor Driver
	4	*
	5	* Copyright (C) 2010 Texas Instruments
	6	* Author: Hemanth V <[email protected]>
	7	*
	8	* This program is free software; you can redistribute it and/or modify it
	9	* under the terms of the GNU General Public License version 2 as published by
	10	* the Free Software Foundation.
	11	*
	12	* This program is distributed in the hope that it will be useful, but WITHOUT
	13	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	14	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	15	* more details.
	16	*
	17	* You should have received a copy of the GNU General Public License along with
	18	* this program. If not, see <http://www.gnu.org/licenses/>.
	19	*/
	20	#include <linux/i2c.h>
	21	#include <linux/slab.h>
	22	#include <linux/mutex.h>
	23	#include <linux/platform_device.h>
	24	#include <linux/delay.h>
eb12a679	25	#include <linux/module.h>
7efe15f2 H	26
	27	#define BH1780_REG_CONTROL 0x80
	28	#define BH1780_REG_PARTID 0x8A
	29	#define BH1780_REG_MANFID 0x8B
	30	#define BH1780_REG_DLOW 0x8C
	31	#define BH1780_REG_DHIGH 0x8D
	32
	33	#define BH1780_REVMASK (0xf)
	34	#define BH1780_POWMASK (0x3)
	35	#define BH1780_POFF (0x0)
	36	#define BH1780_PON (0x3)
	37
	38	/* power on settling time in ms */
	39	#define BH1780_PON_DELAY 2
	40
	41	struct bh1780_data {
	42	struct i2c_client *client;
	43	int power_state;
	44	/* lock for sysfs operations */
	45	struct mutex lock;
	46	};
	47
	48	static int bh1780_write(struct bh1780_data ddata, u8 reg, u8 val, char msg)
	49	{
	50	int ret = i2c_smbus_write_byte_data(ddata->client, reg, val);
	51	if (ret < 0)
	52	dev_err(&ddata->client->dev,
85ee7a1d JP	53	"i2c_smbus_write_byte_data failed error %d Register (%s)\n",
85ee7a1d JP	54	ret, msg);
7efe15f2 H	55	return ret;
	56	}
	57
	58	static int bh1780_read(struct bh1780_data ddata, u8 reg, char msg)
	59	{
	60	int ret = i2c_smbus_read_byte_data(ddata->client, reg);
	61	if (ret < 0)
	62	dev_err(&ddata->client->dev,
85ee7a1d JP	63	"i2c_smbus_read_byte_data failed error %d Register (%s)\n",
85ee7a1d JP	64	ret, msg);
7efe15f2 H	65	return ret;
	66	}
	67
	68	static ssize_t bh1780_show_lux(struct device *dev,
	69	struct device_attribute attr, char buf)
	70	{
	71	struct platform_device *pdev = to_platform_device(dev);
	72	struct bh1780_data *ddata = platform_get_drvdata(pdev);
	73	int lsb, msb;
	74
	75	lsb = bh1780_read(ddata, BH1780_REG_DLOW, "DLOW");
	76	if (lsb < 0)
	77	return lsb;
	78
	79	msb = bh1780_read(ddata, BH1780_REG_DHIGH, "DHIGH");
	80	if (msb < 0)
	81	return msb;
	82
	83	return sprintf(buf, "%d\n", (msb << 8) \| lsb);
	84	}
	85
	86	static ssize_t bh1780_show_power_state(struct device *dev,
	87	struct device_attribute *attr,
	88	char *buf)
	89	{
	90	struct platform_device *pdev = to_platform_device(dev);
	91	struct bh1780_data *ddata = platform_get_drvdata(pdev);
	92	int state;
	93
	94	state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL");
	95	if (state < 0)
	96	return state;
	97
	98	return sprintf(buf, "%d\n", state & BH1780_POWMASK);
	99	}
	100
	101	static ssize_t bh1780_store_power_state(struct device *dev,
	102	struct device_attribute *attr,
	103	const char *buf, size_t count)
	104	{
	105	struct platform_device *pdev = to_platform_device(dev);
	106	struct bh1780_data *ddata = platform_get_drvdata(pdev);
	107	unsigned long val;
	108	int error;
	109
	110	error = strict_strtoul(buf, 0, &val);
	111	if (error)
	112	return error;
	113
	114	if (val < BH1780_POFF \|\| val > BH1780_PON)
	115	return -EINVAL;
	116
	117	mutex_lock(&ddata->lock);
	118
	119	error = bh1780_write(ddata, BH1780_REG_CONTROL, val, "CONTROL");
	120	if (error < 0) {
	121	mutex_unlock(&ddata->lock);
	122	return error;
	123	}
	124
	125	msleep(BH1780_PON_DELAY);
	126	ddata->power_state = val;
	127	mutex_unlock(&ddata->lock);
	128
129	return count;
130	}
131
132	static DEVICE_ATTR(lux, S_IRUGO, bh1780_show_lux, NULL);
133
134	static DEVICE_ATTR(power_state, S_IWUSR \| S_IRUGO,
135	bh1780_show_power_state, bh1780_store_power_state);
136
137	static struct attribute *bh1780_attributes[] = {
138	&dev_attr_power_state.attr,
139	&dev_attr_lux.attr,
140	NULL
141	};
142
143	static const struct attribute_group bh1780_attr_group = {
144	.attrs = bh1780_attributes,
145	};
146
80c8ae28	147	static int bh1780_probe(struct i2c_client *client,
7efe15f2 H	148	const struct i2c_device_id *id)
	149	{
	150	int ret;
	151	struct bh1780_data *ddata = NULL;
	152	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
	153
	154	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) {
	155	ret = -EIO;
	156	goto err_op_failed;
	157	}
	158
	159	ddata = kzalloc(sizeof(struct bh1780_data), GFP_KERNEL);
	160	if (ddata == NULL) {
	161	ret = -ENOMEM;
	162	goto err_op_failed;
	163	}
	164
	165	ddata->client = client;
	166	i2c_set_clientdata(client, ddata);
	167
	168	ret = bh1780_read(ddata, BH1780_REG_PARTID, "PART ID");
	169	if (ret < 0)
	170	goto err_op_failed;
	171
	172	dev_info(&client->dev, "Ambient Light Sensor, Rev : %d\n",
	173	(ret & BH1780_REVMASK));
	174
	175	mutex_init(&ddata->lock);
	176
	177	ret = sysfs_create_group(&client->dev.kobj, &bh1780_attr_group);
	178	if (ret)
	179	goto err_op_failed;
	180
	181	return 0;
	182
	183	err_op_failed:
	184	kfree(ddata);
	185	return ret;
	186	}
	187
486a5c28	188	static int bh1780_remove(struct i2c_client *client)
7efe15f2 H	189	{
	190	struct bh1780_data *ddata;
	191
	192	ddata = i2c_get_clientdata(client);
	193	sysfs_remove_group(&client->dev.kobj, &bh1780_attr_group);
7efe15f2 H	194	kfree(ddata);
	195
	196	return 0;
	197	}
	198
688ef202	199	#ifdef CONFIG_PM_SLEEP
4a7de634	200	static int bh1780_suspend(struct device *dev)
7efe15f2 H	201	{
	202	struct bh1780_data *ddata;
	203	int state, ret;
4a7de634	204	struct i2c_client *client = to_i2c_client(dev);
7efe15f2 H	205
	206	ddata = i2c_get_clientdata(client);
	207	state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL");
	208	if (state < 0)
	209	return state;
	210
	211	ddata->power_state = state & BH1780_POWMASK;
	212
	213	ret = bh1780_write(ddata, BH1780_REG_CONTROL, BH1780_POFF,
	214	"CONTROL");
	215
	216	if (ret < 0)
	217	return ret;
	218
	219	return 0;
	220	}
	221
4a7de634	222	static int bh1780_resume(struct device *dev)
7efe15f2 H	223	{
	224	struct bh1780_data *ddata;
	225	int state, ret;
4a7de634	226	struct i2c_client *client = to_i2c_client(dev);
7efe15f2 H	227
	228	ddata = i2c_get_clientdata(client);
	229	state = ddata->power_state;
7efe15f2 H	230	ret = bh1780_write(ddata, BH1780_REG_CONTROL, state,
	231	"CONTROL");
	232
	233	if (ret < 0)
	234	return ret;
	235
	236	return 0;
	237	}
688ef202 JH	238	#endif /* CONFIG_PM_SLEEP */
688ef202 JH	239
4a7de634	240	static SIMPLE_DEV_PM_OPS(bh1780_pm, bh1780_suspend, bh1780_resume);
7efe15f2 H	241
	242	static const struct i2c_device_id bh1780_id[] = {
	243	{ "bh1780", 0 },
	244	{ },
	245	};
	246
	247	static struct i2c_driver bh1780_driver = {
	248	.probe = bh1780_probe,
2d6bed9c	249	.remove = bh1780_remove,
7efe15f2	250	.id_table = bh1780_id,
7efe15f2	251	.driver = {
4a7de634	252	.name = "bh1780",
688ef202	253	.pm = &bh1780_pm,
a64fe2ed	254	},
7efe15f2 H	255	};
7efe15f2 H	256
a64fe2ed	257	module_i2c_driver(bh1780_driver);
7efe15f2 H	258
	259	MODULE_DESCRIPTION("BH1780GLI Ambient Light Sensor Driver");
	260	MODULE_LICENSE("GPL");
	261	MODULE_AUTHOR("Hemanth V <[email protected]>");