[linux-block.git] / drivers / hwmon / ads1015.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * ads1015.c - lm_sensors driver for ads1015 12-bit 4-input ADC
 * (C) Copyright 2010
 * Dirk Eibach, Guntermann & Drunck GmbH <eibach@gdsys.de>
 *
 * Based on the ads7828 driver by Steve Hardy.
 *
 * Datasheet available at: http://focus.ti.com/lit/ds/symlink/ads1015.pdf
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/of_device.h>
#include <linux/of.h>

#include <linux/platform_data/ads1015.h>

/* ADS1015 registers */
enum {
	ADS1015_CONVERSION = 0,
	ADS1015_CONFIG = 1,
};

/* PGA fullscale voltages in mV */
static const unsigned int fullscale_table[8] = {
	6144, 4096, 2048, 1024, 512, 256, 256, 256 };

/* Data rates in samples per second */
static const unsigned int data_rate_table_1015[8] = {
	128, 250, 490, 920, 1600, 2400, 3300, 3300
};

static const unsigned int data_rate_table_1115[8] = {
	8, 16, 32, 64, 128, 250, 475, 860
};

#define ADS1015_DEFAULT_CHANNELS 0xff
#define ADS1015_DEFAULT_PGA 2
#define ADS1015_DEFAULT_DATA_RATE 4

enum ads1015_chips {
	ads1015,
	ads1115,
};

struct ads1015_data {
	struct device *hwmon_dev;
	struct mutex update_lock; /* mutex protect updates */
	struct ads1015_channel_data channel_data[ADS1015_CHANNELS];
	enum ads1015_chips id;
};

static int ads1015_read_adc(struct i2c_client *client, unsigned int channel)
{
	u16 config;
	struct ads1015_data *data = i2c_get_clientdata(client);
	unsigned int pga = data->channel_data[channel].pga;
	unsigned int data_rate = data->channel_data[channel].data_rate;
	unsigned int conversion_time_ms;
	const unsigned int * const rate_table = data->id == ads1115 ?
		data_rate_table_1115 : data_rate_table_1015;
	int res;

	mutex_lock(&data->update_lock);

	/* get channel parameters */
	res = i2c_smbus_read_word_swapped(client, ADS1015_CONFIG);
	if (res < 0)
		goto err_unlock;
	config = res;
	conversion_time_ms = DIV_ROUND_UP(1000, rate_table[data_rate]);

	/* setup and start single conversion */
	config &= 0x001f;
	config |= (1 << 15) | (1 << 8);
	config |= (channel & 0x0007) << 12;
	config |= (pga & 0x0007) << 9;
	config |= (data_rate & 0x0007) << 5;

	res = i2c_smbus_write_word_swapped(client, ADS1015_CONFIG, config);
	if (res < 0)
		goto err_unlock;

	/* wait until conversion finished */
	msleep(conversion_time_ms);
	res = i2c_smbus_read_word_swapped(client, ADS1015_CONFIG);
	if (res < 0)
		goto err_unlock;
	config = res;
	if (!(config & (1 << 15))) {
		/* conversion not finished in time */
		res = -EIO;
		goto err_unlock;
	}

	res = i2c_smbus_read_word_swapped(client, ADS1015_CONVERSION);

err_unlock:
	mutex_unlock(&data->update_lock);
	return res;
}

static int ads1015_reg_to_mv(struct i2c_client *client, unsigned int channel,
			     s16 reg)
{
	struct ads1015_data *data = i2c_get_clientdata(client);
	unsigned int pga = data->channel_data[channel].pga;
	int fullscale = fullscale_table[pga];
	const int mask = data->id == ads1115 ? 0x7fff : 0x7ff0;

	return DIV_ROUND_CLOSEST(reg * fullscale, mask);
}

/* sysfs callback function */
static ssize_t in_show(struct device *dev, struct device_attribute *da,
		       char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	struct i2c_client *client = to_i2c_client(dev);
	int res;
	int index = attr->index;

	res = ads1015_read_adc(client, index);
	if (res < 0)
		return res;

	return sprintf(buf, "%d\n", ads1015_reg_to_mv(client, index, res));
}

static const struct sensor_device_attribute ads1015_in[] = {
	SENSOR_ATTR_RO(in0_input, in, 0),
	SENSOR_ATTR_RO(in1_input, in, 1),
	SENSOR_ATTR_RO(in2_input, in, 2),
	SENSOR_ATTR_RO(in3_input, in, 3),
	SENSOR_ATTR_RO(in4_input, in, 4),
	SENSOR_ATTR_RO(in5_input, in, 5),
	SENSOR_ATTR_RO(in6_input, in, 6),
	SENSOR_ATTR_RO(in7_input, in, 7),
};

/*
 * Driver interface
 */

static int ads1015_remove(struct i2c_client *client)
{
	struct ads1015_data *data = i2c_get_clientdata(client);
	int k;

	hwmon_device_unregister(data->hwmon_dev);
	for (k = 0; k < ADS1015_CHANNELS; ++k)
		device_remove_file(&client->dev, &ads1015_in[k].dev_attr);
	return 0;
}

#ifdef CONFIG_OF
static int ads1015_get_channels_config_of(struct i2c_client *client)
{
	struct ads1015_data *data = i2c_get_clientdata(client);
	struct device_node *node;

	if (!client->dev.of_node
	    || !of_get_next_child(client->dev.of_node, NULL))
		return -EINVAL;

	for_each_child_of_node(client->dev.of_node, node) {
		u32 pval;
		unsigned int channel;
		unsigned int pga = ADS1015_DEFAULT_PGA;
		unsigned int data_rate = ADS1015_DEFAULT_DATA_RATE;

		if (of_property_read_u32(node, "reg", &pval)) {
			dev_err(&client->dev, "invalid reg on %pOF\n", node);
			continue;
		}

		channel = pval;
		if (channel >= ADS1015_CHANNELS) {
			dev_err(&client->dev,
				"invalid channel index %d on %pOF\n",
				channel, node);
			continue;
		}

		if (!of_property_read_u32(node, "ti,gain", &pval)) {
			pga = pval;
			if (pga > 6) {
				dev_err(&client->dev, "invalid gain on %pOF\n",
					node);
				return -EINVAL;
			}
		}

		if (!of_property_read_u32(node, "ti,datarate", &pval)) {
			data_rate = pval;
			if (data_rate > 7) {
				dev_err(&client->dev,
					"invalid data_rate on %pOF\n", node);
				return -EINVAL;
			}
		}

		data->channel_data[channel].enabled = true;
		data->channel_data[channel].pga = pga;
		data->channel_data[channel].data_rate = data_rate;
	}

	return 0;
}
#endif

static void ads1015_get_channels_config(struct i2c_client *client)
{
	unsigned int k;
	struct ads1015_data *data = i2c_get_clientdata(client);
	struct ads1015_platform_data *pdata = dev_get_platdata(&client->dev);

	/* prefer platform data */
	if (pdata) {
		memcpy(data->channel_data, pdata->channel_data,
		       sizeof(data->channel_data));
		return;
	}

#ifdef CONFIG_OF
	if (!ads1015_get_channels_config_of(client))
		return;
#endif

	/* fallback on default configuration */
	for (k = 0; k < ADS1015_CHANNELS; ++k) {
		data->channel_data[k].enabled = true;
		data->channel_data[k].pga = ADS1015_DEFAULT_PGA;
		data->channel_data[k].data_rate = ADS1015_DEFAULT_DATA_RATE;
	}
}

static int ads1015_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct ads1015_data *data;
	int err;
	unsigned int k;

	data = devm_kzalloc(&client->dev, sizeof(struct ads1015_data),
			    GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	if (client->dev.of_node)
		data->id = (enum ads1015_chips)
			of_device_get_match_data(&client->dev);
	else
		data->id = id->driver_data;
	i2c_set_clientdata(client, data);
	mutex_init(&data->update_lock);

	/* build sysfs attribute group */
	ads1015_get_channels_config(client);
	for (k = 0; k < ADS1015_CHANNELS; ++k) {
		if (!data->channel_data[k].enabled)
			continue;
		err = device_create_file(&client->dev, &ads1015_in[k].dev_attr);
		if (err)
			goto exit_remove;
	}

	data->hwmon_dev = hwmon_device_register(&client->dev);
	if (IS_ERR(data->hwmon_dev)) {
		err = PTR_ERR(data->hwmon_dev);
		goto exit_remove;
	}

	return 0;

exit_remove:
	for (k = 0; k < ADS1015_CHANNELS; ++k)
		device_remove_file(&client->dev, &ads1015_in[k].dev_attr);
	return err;
}

static const struct i2c_device_id ads1015_id[] = {
	{ "ads1015",  ads1015},
	{ "ads1115",  ads1115},
	{ }
};
MODULE_DEVICE_TABLE(i2c, ads1015_id);

static const struct of_device_id __maybe_unused ads1015_of_match[] = {
	{
		.compatible = "ti,ads1015",
		.data = (void *)ads1015
	},
	{
		.compatible = "ti,ads1115",
		.data = (void *)ads1115
	},
	{ },
};
MODULE_DEVICE_TABLE(of, ads1015_of_match);

static struct i2c_driver ads1015_driver = {
	.driver = {
		.name = "ads1015",
		.of_match_table = of_match_ptr(ads1015_of_match),
	},
	.probe = ads1015_probe,
	.remove = ads1015_remove,
	.id_table = ads1015_id,
};

module_i2c_driver(ads1015_driver);

MODULE_AUTHOR("Dirk Eibach <eibach@gdsys.de>");
MODULE_DESCRIPTION("ADS1015 driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
74ba9207	1	// SPDX-License-Identifier: GPL-2.0-or-later
8c22a8f5 DE	2	/*
	3	* ads1015.c - lm_sensors driver for ads1015 12-bit 4-input ADC
	4	* (C) Copyright 2010
	5	* Dirk Eibach, Guntermann & Drunck GmbH <eibach@gdsys.de>
	6	*
	7	* Based on the ads7828 driver by Steve Hardy.
	8	*
	9	* Datasheet available at: http://focus.ti.com/lit/ds/symlink/ads1015.pdf
8c22a8f5 DE	10	*/
	11
	12	#include <linux/module.h>
	13	#include <linux/init.h>
	14	#include <linux/slab.h>
	15	#include <linux/delay.h>
	16	#include <linux/i2c.h>
	17	#include <linux/hwmon.h>
	18	#include <linux/hwmon-sysfs.h>
	19	#include <linux/err.h>
	20	#include <linux/mutex.h>
a140986f	21	#include <linux/of_device.h>
8c22a8f5 DE	22	#include <linux/of.h>
8c22a8f5 DE	23
9010624c	24	#include <linux/platform_data/ads1015.h>
8c22a8f5 DE	25
	26	/* ADS1015 registers */
	27	enum {
	28	ADS1015_CONVERSION = 0,
	29	ADS1015_CONFIG = 1,
	30	};
	31
	32	/* PGA fullscale voltages in mV */
	33	static const unsigned int fullscale_table[8] = {
	34	6144, 4096, 2048, 1024, 512, 256, 256, 256 };
	35
c0046867	36	/* Data rates in samples per second */
60c1f31f ED	37	static const unsigned int data_rate_table_1015[8] = {
	38	128, 250, 490, 920, 1600, 2400, 3300, 3300
	39	};
	40
	41	static const unsigned int data_rate_table_1115[8] = {
	42	8, 16, 32, 64, 128, 250, 475, 860
	43	};
c0046867	44
8c22a8f5	45	#define ADS1015_DEFAULT_CHANNELS 0xff
c0046867 DE	46	#define ADS1015_DEFAULT_PGA 2
c0046867 DE	47	#define ADS1015_DEFAULT_DATA_RATE 4
8c22a8f5	48
60c1f31f ED	49	enum ads1015_chips {
	50	ads1015,
	51	ads1115,
	52	};
	53
8c22a8f5 DE	54	struct ads1015_data {
	55	struct device *hwmon_dev;
	56	struct mutex update_lock; /* mutex protect updates */
c0046867	57	struct ads1015_channel_data channel_data[ADS1015_CHANNELS];
60c1f31f	58	enum ads1015_chips id;
8c22a8f5 DE	59	};
8c22a8f5 DE	60
1196573f	61	static int ads1015_read_adc(struct i2c_client *client, unsigned int channel)
8c22a8f5 DE	62	{
8c22a8f5 DE	63	u16 config;
8c22a8f5	64	struct ads1015_data *data = i2c_get_clientdata(client);
c0046867	65	unsigned int pga = data->channel_data[channel].pga;
c0046867 DE	66	unsigned int data_rate = data->channel_data[channel].data_rate;
c0046867 DE	67	unsigned int conversion_time_ms;
60c1f31f ED	68	const unsigned int * const rate_table = data->id == ads1115 ?
60c1f31f ED	69	data_rate_table_1115 : data_rate_table_1015;
8c22a8f5 DE	70	int res;
	71
	72	mutex_lock(&data->update_lock);
	73
c0046867	74	/* get channel parameters */
90f4102c	75	res = i2c_smbus_read_word_swapped(client, ADS1015_CONFIG);
8c22a8f5 DE	76	if (res < 0)
	77	goto err_unlock;
	78	config = res;
60c1f31f	79	conversion_time_ms = DIV_ROUND_UP(1000, rate_table[data_rate]);
8c22a8f5	80
c0046867 DE	81	/* setup and start single conversion */
	82	config &= 0x001f;
	83	config \|= (1 << 15) \| (1 << 8);
	84	config \|= (channel & 0x0007) << 12;
	85	config \|= (pga & 0x0007) << 9;
	86	config \|= (data_rate & 0x0007) << 5;
8c22a8f5	87
90f4102c	88	res = i2c_smbus_write_word_swapped(client, ADS1015_CONFIG, config);
8c22a8f5 DE	89	if (res < 0)
8c22a8f5 DE	90	goto err_unlock;
c0046867 DE	91
	92	/* wait until conversion finished */
	93	msleep(conversion_time_ms);
90f4102c	94	res = i2c_smbus_read_word_swapped(client, ADS1015_CONFIG);
c0046867 DE	95	if (res < 0)
	96	goto err_unlock;
	97	config = res;
	98	if (!(config & (1 << 15))) {
	99	/* conversion not finished in time */
8c22a8f5 DE	100	res = -EIO;
	101	goto err_unlock;
	102	}
	103
90f4102c	104	res = i2c_smbus_read_word_swapped(client, ADS1015_CONVERSION);
8c22a8f5 DE	105
	106	err_unlock:
	107	mutex_unlock(&data->update_lock);
	108	return res;
	109	}
	110
1196573f GR	111	static int ads1015_reg_to_mv(struct i2c_client *client, unsigned int channel,
	112	s16 reg)
	113	{
	114	struct ads1015_data *data = i2c_get_clientdata(client);
	115	unsigned int pga = data->channel_data[channel].pga;
	116	int fullscale = fullscale_table[pga];
acc14694	117	const int mask = data->id == ads1115 ? 0x7fff : 0x7ff0;
1196573f	118
60c1f31f	119	return DIV_ROUND_CLOSEST(reg * fullscale, mask);
1196573f GR	120	}
1196573f GR	121
8c22a8f5	122	/* sysfs callback function */
7e77d1e7 GR	123	static ssize_t in_show(struct device dev, struct device_attribute da,
7e77d1e7 GR	124	char *buf)
8c22a8f5 DE	125	{
	126	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	127	struct i2c_client *client = to_i2c_client(dev);
8c22a8f5	128	int res;
1196573f	129	int index = attr->index;
8c22a8f5	130
1196573f GR	131	res = ads1015_read_adc(client, index);
	132	if (res < 0)
	133	return res;
8c22a8f5	134
1196573f	135	return sprintf(buf, "%d\n", ads1015_reg_to_mv(client, index, res));
8c22a8f5 DE	136	}
8c22a8f5 DE	137
fdf241a8	138	static const struct sensor_device_attribute ads1015_in[] = {
7e77d1e7 GR	139	SENSOR_ATTR_RO(in0_input, in, 0),
	140	SENSOR_ATTR_RO(in1_input, in, 1),
	141	SENSOR_ATTR_RO(in2_input, in, 2),
	142	SENSOR_ATTR_RO(in3_input, in, 3),
	143	SENSOR_ATTR_RO(in4_input, in, 4),
	144	SENSOR_ATTR_RO(in5_input, in, 5),
	145	SENSOR_ATTR_RO(in6_input, in, 6),
	146	SENSOR_ATTR_RO(in7_input, in, 7),
8c22a8f5 DE	147	};
	148
	149	/*
	150	* Driver interface
	151	*/
	152
	153	static int ads1015_remove(struct i2c_client *client)
	154	{
	155	struct ads1015_data *data = i2c_get_clientdata(client);
fdf241a8 JD	156	int k;
fdf241a8 JD	157
8c22a8f5	158	hwmon_device_unregister(data->hwmon_dev);
c0046867	159	for (k = 0; k < ADS1015_CHANNELS; ++k)
fdf241a8	160	device_remove_file(&client->dev, &ads1015_in[k].dev_attr);
8c22a8f5 DE	161	return 0;
	162	}
	163
8c22a8f5	164	#ifdef CONFIG_OF
c0046867 DE	165	static int ads1015_get_channels_config_of(struct i2c_client *client)
	166	{
	167	struct ads1015_data *data = i2c_get_clientdata(client);
	168	struct device_node *node;
	169
	170	if (!client->dev.of_node
	171	\|\| !of_get_next_child(client->dev.of_node, NULL))
	172	return -EINVAL;
	173
	174	for_each_child_of_node(client->dev.of_node, node) {
8e35762f	175	u32 pval;
c0046867 DE	176	unsigned int channel;
	177	unsigned int pga = ADS1015_DEFAULT_PGA;
	178	unsigned int data_rate = ADS1015_DEFAULT_DATA_RATE;
	179
8e35762f	180	if (of_property_read_u32(node, "reg", &pval)) {
bb923fdc	181	dev_err(&client->dev, "invalid reg on %pOF\n", node);
c0046867 DE	182	continue;
	183	}
	184
8e35762f	185	channel = pval;
56de1377	186	if (channel >= ADS1015_CHANNELS) {
c0046867	187	dev_err(&client->dev,
bb923fdc RH	188	"invalid channel index %d on %pOF\n",
bb923fdc RH	189	channel, node);
c0046867 DE	190	continue;
	191	}
	192
8e35762f AL	193	if (!of_property_read_u32(node, "ti,gain", &pval)) {
8e35762f AL	194	pga = pval;
c0046867	195	if (pga > 6) {
bb923fdc RH	196	dev_err(&client->dev, "invalid gain on %pOF\n",
bb923fdc RH	197	node);
e9814295	198	return -EINVAL;
c0046867 DE	199	}
	200	}
	201
8e35762f AL	202	if (!of_property_read_u32(node, "ti,datarate", &pval)) {
8e35762f AL	203	data_rate = pval;
c0046867 DE	204	if (data_rate > 7) {
c0046867 DE	205	dev_err(&client->dev,
bb923fdc	206	"invalid data_rate on %pOF\n", node);
e9814295	207	return -EINVAL;
c0046867 DE	208	}
	209	}
	210
	211	data->channel_data[channel].enabled = true;
	212	data->channel_data[channel].pga = pga;
	213	data->channel_data[channel].data_rate = data_rate;
	214	}
	215
	216	return 0;
	217	}
8c22a8f5 DE	218	#endif
8c22a8f5 DE	219
c0046867 DE	220	static void ads1015_get_channels_config(struct i2c_client *client)
	221	{
	222	unsigned int k;
	223	struct ads1015_data *data = i2c_get_clientdata(client);
	224	struct ads1015_platform_data *pdata = dev_get_platdata(&client->dev);
	225
8c22a8f5	226	/* prefer platform data */
c0046867 DE	227	if (pdata) {
	228	memcpy(data->channel_data, pdata->channel_data,
	229	sizeof(data->channel_data));
	230	return;
	231	}
8c22a8f5 DE	232
8c22a8f5 DE	233	#ifdef CONFIG_OF
c0046867 DE	234	if (!ads1015_get_channels_config_of(client))
c0046867 DE	235	return;
8c22a8f5 DE	236	#endif
	237
	238	/* fallback on default configuration */
c0046867 DE	239	for (k = 0; k < ADS1015_CHANNELS; ++k) {
	240	data->channel_data[k].enabled = true;
	241	data->channel_data[k].pga = ADS1015_DEFAULT_PGA;
	242	data->channel_data[k].data_rate = ADS1015_DEFAULT_DATA_RATE;
	243	}
8c22a8f5 DE	244	}
	245
	246	static int ads1015_probe(struct i2c_client *client,
	247	const struct i2c_device_id *id)
	248	{
	249	struct ads1015_data *data;
	250	int err;
8c22a8f5	251	unsigned int k;
8c22a8f5	252
57457e31 GR	253	data = devm_kzalloc(&client->dev, sizeof(struct ads1015_data),
	254	GFP_KERNEL);
	255	if (!data)
	256	return -ENOMEM;
a140986f JMC	257
	258	if (client->dev.of_node)
	259	data->id = (enum ads1015_chips)
	260	of_device_get_match_data(&client->dev);
	261	else
	262	data->id = id->driver_data;
8c22a8f5 DE	263	i2c_set_clientdata(client, data);
	264	mutex_init(&data->update_lock);
	265
	266	/* build sysfs attribute group */
c0046867 DE	267	ads1015_get_channels_config(client);
	268	for (k = 0; k < ADS1015_CHANNELS; ++k) {
	269	if (!data->channel_data[k].enabled)
8c22a8f5	270	continue;
fdf241a8 JD	271	err = device_create_file(&client->dev, &ads1015_in[k].dev_attr);
fdf241a8 JD	272	if (err)
363434b5	273	goto exit_remove;
8c22a8f5	274	}
8c22a8f5 DE	275
	276	data->hwmon_dev = hwmon_device_register(&client->dev);
	277	if (IS_ERR(data->hwmon_dev)) {
	278	err = PTR_ERR(data->hwmon_dev);
	279	goto exit_remove;
	280	}
	281
	282	return 0;
	283
	284	exit_remove:
c0046867	285	for (k = 0; k < ADS1015_CHANNELS; ++k)
fdf241a8	286	device_remove_file(&client->dev, &ads1015_in[k].dev_attr);
8c22a8f5 DE	287	return err;
	288	}
	289
	290	static const struct i2c_device_id ads1015_id[] = {
60c1f31f ED	291	{ "ads1015", ads1015},
60c1f31f ED	292	{ "ads1115", ads1115},
8c22a8f5 DE	293	{ }
	294	};
	295	MODULE_DEVICE_TABLE(i2c, ads1015_id);
	296
eb3cb6d5	297	static const struct of_device_id __maybe_unused ads1015_of_match[] = {
a140986f JMC	298	{
	299	.compatible = "ti,ads1015",
	300	.data = (void *)ads1015
	301	},
	302	{
	303	.compatible = "ti,ads1115",
	304	.data = (void *)ads1115
	305	},
	306	{ },
	307	};
	308	MODULE_DEVICE_TABLE(of, ads1015_of_match);
	309
8c22a8f5 DE	310	static struct i2c_driver ads1015_driver = {
	311	.driver = {
	312	.name = "ads1015",
a140986f	313	.of_match_table = of_match_ptr(ads1015_of_match),
8c22a8f5 DE	314	},
	315	.probe = ads1015_probe,
	316	.remove = ads1015_remove,
	317	.id_table = ads1015_id,
	318	};
	319
f0967eea	320	module_i2c_driver(ads1015_driver);
8c22a8f5 DE	321
	322	MODULE_AUTHOR("Dirk Eibach <eibach@gdsys.de>");
	323	MODULE_DESCRIPTION("ADS1015 driver");
	324	MODULE_LICENSE("GPL");