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

/*
 * bh1780gli.c
 * ROHM Ambient Light Sensor Driver
 *
 * Copyright (C) 2010 Texas Instruments
 * Author: Hemanth V <hemanthv@ti.com>
 *
 * 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>
#include <linux/of.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 = kstrtoul(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 },
	{ },
};

#ifdef CONFIG_OF
static const struct of_device_id of_bh1780_match[] = {
	{ .compatible = "rohm,bh1780gli", },
	{},
};

MODULE_DEVICE_TABLE(of, of_bh1780_match);
#endif

static struct i2c_driver bh1780_driver = {
	.probe		= bh1780_probe,
	.remove		= bh1780_remove,
	.id_table	= bh1780_id,
	.driver = {
		.name = "bh1780",
		.pm	= &bh1780_pm,
		.of_match_table = of_match_ptr(of_bh1780_match),
	},
};

module_i2c_driver(bh1780_driver);

MODULE_DESCRIPTION("BH1780GLI Ambient Light Sensor Driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Hemanth V <hemanthv@ti.com>");
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 <hemanthv@ti.com>
	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>
bc342689	26	#include <linux/of.h>
7efe15f2 H	27
	28	#define BH1780_REG_CONTROL 0x80
	29	#define BH1780_REG_PARTID 0x8A
	30	#define BH1780_REG_MANFID 0x8B
	31	#define BH1780_REG_DLOW 0x8C
	32	#define BH1780_REG_DHIGH 0x8D
	33
	34	#define BH1780_REVMASK (0xf)
	35	#define BH1780_POWMASK (0x3)
	36	#define BH1780_POFF (0x0)
	37	#define BH1780_PON (0x3)
	38
	39	/* power on settling time in ms */
	40	#define BH1780_PON_DELAY 2
	41
	42	struct bh1780_data {
	43	struct i2c_client *client;
	44	int power_state;
	45	/* lock for sysfs operations */
	46	struct mutex lock;
	47	};
	48
	49	static int bh1780_write(struct bh1780_data ddata, u8 reg, u8 val, char msg)
	50	{
	51	int ret = i2c_smbus_write_byte_data(ddata->client, reg, val);
	52	if (ret < 0)
	53	dev_err(&ddata->client->dev,
85ee7a1d JP	54	"i2c_smbus_write_byte_data failed error %d Register (%s)\n",
85ee7a1d JP	55	ret, msg);
7efe15f2 H	56	return ret;
	57	}
	58
	59	static int bh1780_read(struct bh1780_data ddata, u8 reg, char msg)
	60	{
	61	int ret = i2c_smbus_read_byte_data(ddata->client, reg);
	62	if (ret < 0)
	63	dev_err(&ddata->client->dev,
85ee7a1d JP	64	"i2c_smbus_read_byte_data failed error %d Register (%s)\n",
85ee7a1d JP	65	ret, msg);
7efe15f2 H	66	return ret;
	67	}
	68
	69	static ssize_t bh1780_show_lux(struct device *dev,
	70	struct device_attribute attr, char buf)
	71	{
	72	struct platform_device *pdev = to_platform_device(dev);
	73	struct bh1780_data *ddata = platform_get_drvdata(pdev);
	74	int lsb, msb;
	75
	76	lsb = bh1780_read(ddata, BH1780_REG_DLOW, "DLOW");
	77	if (lsb < 0)
	78	return lsb;
	79
	80	msb = bh1780_read(ddata, BH1780_REG_DHIGH, "DHIGH");
	81	if (msb < 0)
	82	return msb;
	83
	84	return sprintf(buf, "%d\n", (msb << 8) \| lsb);
	85	}
	86
	87	static ssize_t bh1780_show_power_state(struct device *dev,
	88	struct device_attribute *attr,
	89	char *buf)
	90	{
	91	struct platform_device *pdev = to_platform_device(dev);
	92	struct bh1780_data *ddata = platform_get_drvdata(pdev);
	93	int state;
	94
	95	state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL");
	96	if (state < 0)
	97	return state;
	98
	99	return sprintf(buf, "%d\n", state & BH1780_POWMASK);
	100	}
	101
	102	static ssize_t bh1780_store_power_state(struct device *dev,
	103	struct device_attribute *attr,
	104	const char *buf, size_t count)
	105	{
	106	struct platform_device *pdev = to_platform_device(dev);
	107	struct bh1780_data *ddata = platform_get_drvdata(pdev);
	108	unsigned long val;
	109	int error;
	110
f7b41276	111	error = kstrtoul(buf, 0, &val);
7efe15f2 H	112	if (error)
	113	return error;
	114
	115	if (val < BH1780_POFF \|\| val > BH1780_PON)
	116	return -EINVAL;
	117
	118	mutex_lock(&ddata->lock);
	119
	120	error = bh1780_write(ddata, BH1780_REG_CONTROL, val, "CONTROL");
	121	if (error < 0) {
	122	mutex_unlock(&ddata->lock);
	123	return error;
	124	}
	125
	126	msleep(BH1780_PON_DELAY);
	127	ddata->power_state = val;
	128	mutex_unlock(&ddata->lock);
	129
	130	return count;
	131	}
	132
	133	static DEVICE_ATTR(lux, S_IRUGO, bh1780_show_lux, NULL);
	134
	135	static DEVICE_ATTR(power_state, S_IWUSR \| S_IRUGO,
	136	bh1780_show_power_state, bh1780_store_power_state);
	137
	138	static struct attribute *bh1780_attributes[] = {
	139	&dev_attr_power_state.attr,
	140	&dev_attr_lux.attr,
	141	NULL
	142	};
	143
	144	static const struct attribute_group bh1780_attr_group = {
	145	.attrs = bh1780_attributes,
	146	};
	147
80c8ae28	148	static int bh1780_probe(struct i2c_client *client,
7efe15f2 H	149	const struct i2c_device_id *id)
	150	{
	151	int ret;
	152	struct bh1780_data *ddata = NULL;
	153	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
	154
	155	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) {
	156	ret = -EIO;
	157	goto err_op_failed;
	158	}
	159
	160	ddata = kzalloc(sizeof(struct bh1780_data), GFP_KERNEL);
	161	if (ddata == NULL) {
	162	ret = -ENOMEM;
	163	goto err_op_failed;
	164	}
	165
	166	ddata->client = client;
	167	i2c_set_clientdata(client, ddata);
	168
	169	ret = bh1780_read(ddata, BH1780_REG_PARTID, "PART ID");
	170	if (ret < 0)
	171	goto err_op_failed;
	172
	173	dev_info(&client->dev, "Ambient Light Sensor, Rev : %d\n",
	174	(ret & BH1780_REVMASK));
	175
	176	mutex_init(&ddata->lock);
	177
	178	ret = sysfs_create_group(&client->dev.kobj, &bh1780_attr_group);
	179	if (ret)
	180	goto err_op_failed;
	181
	182	return 0;
	183
	184	err_op_failed:
	185	kfree(ddata);
	186	return ret;
	187	}
	188
486a5c28	189	static int bh1780_remove(struct i2c_client *client)
7efe15f2 H	190	{
	191	struct bh1780_data *ddata;
	192
	193	ddata = i2c_get_clientdata(client);
	194	sysfs_remove_group(&client->dev.kobj, &bh1780_attr_group);
7efe15f2 H	195	kfree(ddata);
	196
	197	return 0;
	198	}
	199
688ef202	200	#ifdef CONFIG_PM_SLEEP
4a7de634	201	static int bh1780_suspend(struct device *dev)
7efe15f2 H	202	{
	203	struct bh1780_data *ddata;
	204	int state, ret;
4a7de634	205	struct i2c_client *client = to_i2c_client(dev);
7efe15f2 H	206
	207	ddata = i2c_get_clientdata(client);
	208	state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL");
	209	if (state < 0)
	210	return state;
	211
	212	ddata->power_state = state & BH1780_POWMASK;
	213
	214	ret = bh1780_write(ddata, BH1780_REG_CONTROL, BH1780_POFF,
	215	"CONTROL");
	216
	217	if (ret < 0)
	218	return ret;
	219
	220	return 0;
	221	}
	222
4a7de634	223	static int bh1780_resume(struct device *dev)
7efe15f2 H	224	{
	225	struct bh1780_data *ddata;
	226	int state, ret;
4a7de634	227	struct i2c_client *client = to_i2c_client(dev);
7efe15f2 H	228
	229	ddata = i2c_get_clientdata(client);
	230	state = ddata->power_state;
7efe15f2 H	231	ret = bh1780_write(ddata, BH1780_REG_CONTROL, state,
	232	"CONTROL");
	233
	234	if (ret < 0)
	235	return ret;
	236
	237	return 0;
	238	}
688ef202 JH	239	#endif /* CONFIG_PM_SLEEP */
688ef202 JH	240
4a7de634	241	static SIMPLE_DEV_PM_OPS(bh1780_pm, bh1780_suspend, bh1780_resume);
7efe15f2 H	242
	243	static const struct i2c_device_id bh1780_id[] = {
	244	{ "bh1780", 0 },
	245	{ },
	246	};
	247
bc342689 LW	248	#ifdef CONFIG_OF
	249	static const struct of_device_id of_bh1780_match[] = {
	250	{ .compatible = "rohm,bh1780gli", },
	251	{},
	252	};
	253
	254	MODULE_DEVICE_TABLE(of, of_bh1780_match);
	255	#endif
	256
7efe15f2 H	257	static struct i2c_driver bh1780_driver = {
7efe15f2 H	258	.probe = bh1780_probe,
2d6bed9c	259	.remove = bh1780_remove,
7efe15f2	260	.id_table = bh1780_id,
7efe15f2	261	.driver = {
4a7de634	262	.name = "bh1780",
688ef202	263	.pm = &bh1780_pm,
bc342689	264	.of_match_table = of_match_ptr(of_bh1780_match),
a64fe2ed	265	},
7efe15f2 H	266	};
7efe15f2 H	267
a64fe2ed	268	module_i2c_driver(bh1780_driver);
7efe15f2 H	269
	270	MODULE_DESCRIPTION("BH1780GLI Ambient Light Sensor Driver");
	271	MODULE_LICENSE("GPL");
	272	MODULE_AUTHOR("Hemanth V <hemanthv@ti.com>");