[linux-2.6-block.git] / drivers / hwmon / tmp421.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* tmp421.c
 *
 * Copyright (C) 2009 Andre Prendel <andre.prendel@gmx.de>
 * Preliminary support by:
 * Melvin Rook, Raymond Ng
 */

/*
 * Driver for the Texas Instruments TMP421 SMBus temperature sensor IC.
 * Supported models: TMP421, TMP422, TMP423, TMP441, TMP442
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.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.h>
#include <linux/sysfs.h>

/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2a, 0x4c, 0x4d, 0x4e, 0x4f,
					     I2C_CLIENT_END };

enum chips { tmp421, tmp422, tmp423, tmp441, tmp442 };

#define MAX_CHANNELS				4
/* The TMP421 registers */
#define TMP421_STATUS_REG			0x08
#define TMP421_CONFIG_REG_1			0x09
#define TMP421_CONFIG_REG_2			0x0A
#define TMP421_CONFIG_REG_REN(x)		(BIT(3 + (x)))
#define TMP421_CONFIG_REG_REN_MASK		GENMASK(6, 3)
#define TMP421_CONVERSION_RATE_REG		0x0B
#define TMP421_N_FACTOR_REG_1			0x21
#define TMP421_MANUFACTURER_ID_REG		0xFE
#define TMP421_DEVICE_ID_REG			0xFF

static const u8 TMP421_TEMP_MSB[MAX_CHANNELS]	= { 0x00, 0x01, 0x02, 0x03 };
static const u8 TMP421_TEMP_LSB[MAX_CHANNELS]	= { 0x10, 0x11, 0x12, 0x13 };

/* Flags */
#define TMP421_CONFIG_SHUTDOWN			0x40
#define TMP421_CONFIG_RANGE			0x04

/* Manufacturer / Device ID's */
#define TMP421_MANUFACTURER_ID			0x55
#define TMP421_DEVICE_ID			0x21
#define TMP422_DEVICE_ID			0x22
#define TMP423_DEVICE_ID			0x23
#define TMP441_DEVICE_ID			0x41
#define TMP442_DEVICE_ID			0x42

static const struct i2c_device_id tmp421_id[] = {
	{ "tmp421", 2 },
	{ "tmp422", 3 },
	{ "tmp423", 4 },
	{ "tmp441", 2 },
	{ "tmp442", 3 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tmp421_id);

static const struct of_device_id __maybe_unused tmp421_of_match[] = {
	{
		.compatible = "ti,tmp421",
		.data = (void *)2
	},
	{
		.compatible = "ti,tmp422",
		.data = (void *)3
	},
	{
		.compatible = "ti,tmp423",
		.data = (void *)4
	},
	{
		.compatible = "ti,tmp441",
		.data = (void *)2
	},
	{
		.compatible = "ti,tmp442",
		.data = (void *)3
	},
	{ },
};
MODULE_DEVICE_TABLE(of, tmp421_of_match);

struct tmp421_channel {
	const char *label;
	bool enabled;
	s16 temp;
};

struct tmp421_data {
	struct i2c_client *client;
	struct mutex update_lock;
	u32 temp_config[MAX_CHANNELS + 1];
	struct hwmon_channel_info temp_info;
	const struct hwmon_channel_info *info[2];
	struct hwmon_chip_info chip;
	bool valid;
	unsigned long last_updated;
	unsigned long channels;
	u8 config;
	struct tmp421_channel channel[MAX_CHANNELS];
};

static int temp_from_raw(u16 reg, bool extended)
{
	/* Mask out status bits */
	int temp = reg & ~0xf;

	if (extended)
		temp = temp - 64 * 256;
	else
		temp = (s16)temp;

	return DIV_ROUND_CLOSEST(temp * 1000, 256);
}

static int tmp421_update_device(struct tmp421_data *data)
{
	struct i2c_client *client = data->client;
	int ret = 0;
	int i;

	mutex_lock(&data->update_lock);

	if (time_after(jiffies, data->last_updated + (HZ / 2)) ||
	    !data->valid) {
		ret = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
		if (ret < 0)
			goto exit;
		data->config = ret;

		for (i = 0; i < data->channels; i++) {
			ret = i2c_smbus_read_byte_data(client, TMP421_TEMP_MSB[i]);
			if (ret < 0)
				goto exit;
			data->channel[i].temp = ret << 8;

			ret = i2c_smbus_read_byte_data(client, TMP421_TEMP_LSB[i]);
			if (ret < 0)
				goto exit;
			data->channel[i].temp |= ret;
		}
		data->last_updated = jiffies;
		data->valid = true;
	}

exit:
	mutex_unlock(&data->update_lock);

	if (ret < 0) {
		data->valid = false;
		return ret;
	}

	return 0;
}

static int tmp421_enable_channels(struct tmp421_data *data)
{
	int err;
	struct i2c_client *client = data->client;
	struct device *dev = &client->dev;
	int old = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_2);
	int new, i;

	if (old < 0) {
		dev_err(dev, "error reading register, can't disable channels\n");
		return old;
	}

	new = old & ~TMP421_CONFIG_REG_REN_MASK;
	for (i = 0; i < data->channels; i++)
		if (data->channel[i].enabled)
			new |= TMP421_CONFIG_REG_REN(i);

	if (new == old)
		return 0;

	err = i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_2, new);
	if (err < 0)
		dev_err(dev, "error writing register, can't disable channels\n");

	return err;
}

static int tmp421_read(struct device *dev, enum hwmon_sensor_types type,
		       u32 attr, int channel, long *val)
{
	struct tmp421_data *tmp421 = dev_get_drvdata(dev);
	int ret = 0;

	ret = tmp421_update_device(tmp421);
	if (ret)
		return ret;

	switch (attr) {
	case hwmon_temp_input:
		if (!tmp421->channel[channel].enabled)
			return -ENODATA;
		*val = temp_from_raw(tmp421->channel[channel].temp,
				     tmp421->config & TMP421_CONFIG_RANGE);
		return 0;
	case hwmon_temp_fault:
		if (!tmp421->channel[channel].enabled)
			return -ENODATA;
		/*
		 * Any of OPEN or /PVLD bits indicate a hardware mulfunction
		 * and the conversion result may be incorrect
		 */
		*val = !!(tmp421->channel[channel].temp & 0x03);
		return 0;
	case hwmon_temp_enable:
		*val = tmp421->channel[channel].enabled;
		return 0;
	default:
		return -EOPNOTSUPP;
	}

}

static int tmp421_read_string(struct device *dev, enum hwmon_sensor_types type,
			     u32 attr, int channel, const char **str)
{
	struct tmp421_data *data = dev_get_drvdata(dev);

	*str = data->channel[channel].label;

	return 0;
}

static int tmp421_write(struct device *dev, enum hwmon_sensor_types type,
			u32 attr, int channel, long val)
{
	struct tmp421_data *data = dev_get_drvdata(dev);
	int ret;

	switch (attr) {
	case hwmon_temp_enable:
		data->channel[channel].enabled = val;
		ret = tmp421_enable_channels(data);
		break;
	default:
	    ret = -EOPNOTSUPP;
	}

	return ret;
}

static umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type,
				 u32 attr, int channel)
{
	switch (attr) {
	case hwmon_temp_fault:
	case hwmon_temp_input:
		return 0444;
	case hwmon_temp_label:
		return 0444;
	case hwmon_temp_enable:
		return 0644;
	default:
		return 0;
	}
}

static int tmp421_init_client(struct tmp421_data *data)
{
	int config, config_orig;
	struct i2c_client *client = data->client;

	/* Set the conversion rate to 2 Hz */
	i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05);

	/* Start conversions (disable shutdown if necessary) */
	config = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
	if (config < 0) {
		dev_err(&client->dev,
			"Could not read configuration register (%d)\n", config);
		return config;
	}

	config_orig = config;
	config &= ~TMP421_CONFIG_SHUTDOWN;

	if (config != config_orig) {
		dev_info(&client->dev, "Enable monitoring chip\n");
		i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config);
	}

	return tmp421_enable_channels(data);
}

static int tmp421_detect(struct i2c_client *client,
			 struct i2c_board_info *info)
{
	enum chips kind;
	struct i2c_adapter *adapter = client->adapter;
	static const char * const names[] = {
		"TMP421", "TMP422", "TMP423",
		"TMP441", "TMP442"
	};
	int addr = client->addr;
	u8 reg;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		return -ENODEV;

	reg = i2c_smbus_read_byte_data(client, TMP421_MANUFACTURER_ID_REG);
	if (reg != TMP421_MANUFACTURER_ID)
		return -ENODEV;

	reg = i2c_smbus_read_byte_data(client, TMP421_CONVERSION_RATE_REG);
	if (reg & 0xf8)
		return -ENODEV;

	reg = i2c_smbus_read_byte_data(client, TMP421_STATUS_REG);
	if (reg & 0x7f)
		return -ENODEV;

	reg = i2c_smbus_read_byte_data(client, TMP421_DEVICE_ID_REG);
	switch (reg) {
	case TMP421_DEVICE_ID:
		kind = tmp421;
		break;
	case TMP422_DEVICE_ID:
		if (addr == 0x2a)
			return -ENODEV;
		kind = tmp422;
		break;
	case TMP423_DEVICE_ID:
		if (addr != 0x4c && addr != 0x4d)
			return -ENODEV;
		kind = tmp423;
		break;
	case TMP441_DEVICE_ID:
		kind = tmp441;
		break;
	case TMP442_DEVICE_ID:
		if (addr != 0x4c && addr != 0x4d)
			return -ENODEV;
		kind = tmp442;
		break;
	default:
		return -ENODEV;
	}

	strscpy(info->type, tmp421_id[kind].name, I2C_NAME_SIZE);
	dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n",
		 names[kind], client->addr);

	return 0;
}

static int tmp421_probe_child_from_dt(struct i2c_client *client,
				      struct device_node *child,
				      struct tmp421_data *data)

{
	struct device *dev = &client->dev;
	u32 i;
	s32 val;
	int err;

	err = of_property_read_u32(child, "reg", &i);
	if (err) {
		dev_err(dev, "missing reg property of %pOFn\n", child);
		return err;
	}

	if (i >= data->channels) {
		dev_err(dev, "invalid reg %d of %pOFn\n", i, child);
		return -EINVAL;
	}

	of_property_read_string(child, "label", &data->channel[i].label);
	if (data->channel[i].label)
		data->temp_config[i] |= HWMON_T_LABEL;

	data->channel[i].enabled = of_device_is_available(child);

	err = of_property_read_s32(child, "ti,n-factor", &val);
	if (!err) {
		if (i == 0) {
			dev_err(dev, "n-factor can't be set for internal channel\n");
			return -EINVAL;
		}

		if (val > 127 || val < -128) {
			dev_err(dev, "n-factor for channel %d invalid (%d)\n",
				i, val);
			return -EINVAL;
		}
		i2c_smbus_write_byte_data(client, TMP421_N_FACTOR_REG_1 + i - 1,
					  val);
	}

	return 0;
}

static int tmp421_probe_from_dt(struct i2c_client *client, struct tmp421_data *data)
{
	struct device *dev = &client->dev;
	const struct device_node *np = dev->of_node;
	struct device_node *child;
	int err;

	for_each_child_of_node(np, child) {
		if (strcmp(child->name, "channel"))
			continue;

		err = tmp421_probe_child_from_dt(client, child, data);
		if (err) {
			of_node_put(child);
			return err;
		}
	}

	return 0;
}

static const struct hwmon_ops tmp421_ops = {
	.is_visible = tmp421_is_visible,
	.read = tmp421_read,
	.read_string = tmp421_read_string,
	.write = tmp421_write,
};

static int tmp421_probe(struct i2c_client *client)
{
	struct device *dev = &client->dev;
	struct device *hwmon_dev;
	struct tmp421_data *data;
	int i, err;

	data = devm_kzalloc(dev, sizeof(struct tmp421_data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	mutex_init(&data->update_lock);
	if (client->dev.of_node)
		data->channels = (unsigned long)
			of_device_get_match_data(&client->dev);
	else
		data->channels = i2c_match_id(tmp421_id, client)->driver_data;
	data->client = client;

	for (i = 0; i < data->channels; i++) {
		data->temp_config[i] = HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_ENABLE;
		data->channel[i].enabled = true;
	}

	err = tmp421_probe_from_dt(client, data);
	if (err)
		return err;

	err = tmp421_init_client(data);
	if (err)
		return err;

	data->chip.ops = &tmp421_ops;
	data->chip.info = data->info;

	data->info[0] = &data->temp_info;

	data->temp_info.type = hwmon_temp;
	data->temp_info.config = data->temp_config;

	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
							 data,
							 &data->chip,
							 NULL);
	return PTR_ERR_OR_ZERO(hwmon_dev);
}

static struct i2c_driver tmp421_driver = {
	.class = I2C_CLASS_HWMON,
	.driver = {
		.name	= "tmp421",
		.of_match_table = of_match_ptr(tmp421_of_match),
	},
	.probe = tmp421_probe,
	.id_table = tmp421_id,
	.detect = tmp421_detect,
	.address_list = normal_i2c,
};

module_i2c_driver(tmp421_driver);

MODULE_AUTHOR("Andre Prendel <andre.prendel@gmx.de>");
MODULE_DESCRIPTION("Texas Instruments TMP421/422/423/441/442 temperature sensor driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
c942fddf	1	// SPDX-License-Identifier: GPL-2.0-or-later
9410700b AP	2	/* tmp421.c
	3	*
	4	* Copyright (C) 2009 Andre Prendel <andre.prendel@gmx.de>
	5	* Preliminary support by:
	6	* Melvin Rook, Raymond Ng
9410700b AP	7	*/
	8
	9	/*
	10	* Driver for the Texas Instruments TMP421 SMBus temperature sensor IC.
05c77ab2	11	* Supported models: TMP421, TMP422, TMP423, TMP441, TMP442
9410700b AP	12	*/
	13
	14	#include <linux/module.h>
	15	#include <linux/init.h>
	16	#include <linux/slab.h>
	17	#include <linux/jiffies.h>
	18	#include <linux/i2c.h>
	19	#include <linux/hwmon.h>
	20	#include <linux/hwmon-sysfs.h>
	21	#include <linux/err.h>
	22	#include <linux/mutex.h>
39f03438	23	#include <linux/of.h>
9410700b AP	24	#include <linux/sysfs.h>
	25
	26	/* Addresses to scan */
918ee91c JD	27	static const unsigned short normal_i2c[] = { 0x2a, 0x4c, 0x4d, 0x4e, 0x4f,
918ee91c JD	28	I2C_CLIENT_END };
9410700b	29
05c77ab2	30	enum chips { tmp421, tmp422, tmp423, tmp441, tmp442 };
9410700b	31
cae02339	32	#define MAX_CHANNELS 4
9410700b	33	/* The TMP421 registers */
a63ee9d8	34	#define TMP421_STATUS_REG 0x08
9410700b	35	#define TMP421_CONFIG_REG_1 0x09
f3fbf4b8 KA	36	#define TMP421_CONFIG_REG_2 0x0A
	37	#define TMP421_CONFIG_REG_REN(x) (BIT(3 + (x)))
	38	#define TMP421_CONFIG_REG_REN_MASK GENMASK(6, 3)
9410700b	39	#define TMP421_CONVERSION_RATE_REG 0x0B
3fba10dc	40	#define TMP421_N_FACTOR_REG_1 0x21
9410700b AP	41	#define TMP421_MANUFACTURER_ID_REG 0xFE
	42	#define TMP421_DEVICE_ID_REG 0xFF
	43
cae02339 KA	44	static const u8 TMP421_TEMP_MSB[MAX_CHANNELS] = { 0x00, 0x01, 0x02, 0x03 };
cae02339 KA	45	static const u8 TMP421_TEMP_LSB[MAX_CHANNELS] = { 0x10, 0x11, 0x12, 0x13 };
9410700b AP	46
	47	/* Flags */
	48	#define TMP421_CONFIG_SHUTDOWN 0x40
	49	#define TMP421_CONFIG_RANGE 0x04
	50
	51	/* Manufacturer / Device ID's */
	52	#define TMP421_MANUFACTURER_ID 0x55
	53	#define TMP421_DEVICE_ID 0x21
	54	#define TMP422_DEVICE_ID 0x22
	55	#define TMP423_DEVICE_ID 0x23
05c77ab2 GR	56	#define TMP441_DEVICE_ID 0x41
05c77ab2 GR	57	#define TMP442_DEVICE_ID 0x42
9410700b AP	58
9410700b AP	59	static const struct i2c_device_id tmp421_id[] = {
8d59582a JD	60	{ "tmp421", 2 },
	61	{ "tmp422", 3 },
	62	{ "tmp423", 4 },
05c77ab2 GR	63	{ "tmp441", 2 },
05c77ab2 GR	64	{ "tmp442", 3 },
9410700b AP	65	{ }
	66	};
	67	MODULE_DEVICE_TABLE(i2c, tmp421_id);
	68
bd7d56a7	69	static const struct of_device_id __maybe_unused tmp421_of_match[] = {
a1253027 JMC	70	{
	71	.compatible = "ti,tmp421",
	72	.data = (void *)2
	73	},
	74	{
	75	.compatible = "ti,tmp422",
	76	.data = (void *)3
	77	},
	78	{
	79	.compatible = "ti,tmp423",
	80	.data = (void *)4
	81	},
	82	{
	83	.compatible = "ti,tmp441",
	84	.data = (void *)2
	85	},
	86	{
f422449b	87	.compatible = "ti,tmp442",
a1253027 JMC	88	.data = (void *)3
	89	},
	90	{ },
	91	};
	92	MODULE_DEVICE_TABLE(of, tmp421_of_match);
	93
5e3dbeac	94	struct tmp421_channel {
c1143d1b	95	const char *label;
45e9bda4	96	bool enabled;
5e3dbeac KA	97	s16 temp;
	98	};
	99
9410700b	100	struct tmp421_data {
276dac80	101	struct i2c_client *client;
9410700b	102	struct mutex update_lock;
cae02339	103	u32 temp_config[MAX_CHANNELS + 1];
bb43cc45 GR	104	struct hwmon_channel_info temp_info;
	105	const struct hwmon_channel_info *info[2];
	106	struct hwmon_chip_info chip;
952a11ca	107	bool valid;
9410700b	108	unsigned long last_updated;
a1253027	109	unsigned long channels;
9410700b	110	u8 config;
5e3dbeac	111	struct tmp421_channel channel[MAX_CHANNELS];
9410700b AP	112	};
9410700b AP	113
724e8af8	114	static int temp_from_raw(u16 reg, bool extended)
9410700b	115	{
a44908d7 JD	116	/* Mask out status bits */
a44908d7 JD	117	int temp = reg & ~0xf;
9410700b	118
724e8af8 PF	119	if (extended)
	120	temp = temp - 64 * 256;
	121	else
	122	temp = (s16)temp;
9410700b	123
724e8af8	124	return DIV_ROUND_CLOSEST(temp * 1000, 256);
9410700b AP	125	}
9410700b AP	126
2938b297	127	static int tmp421_update_device(struct tmp421_data *data)
9410700b	128	{
276dac80	129	struct i2c_client *client = data->client;
2938b297	130	int ret = 0;
9410700b AP	131	int i;
	132
	133	mutex_lock(&data->update_lock);
	134
5ff02752 KR	135	if (time_after(jiffies, data->last_updated + (HZ / 2)) \|\|
5ff02752 KR	136	!data->valid) {
2938b297 PF	137	ret = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
	138	if (ret < 0)
	139	goto exit;
	140	data->config = ret;
9410700b	141
8d59582a	142	for (i = 0; i < data->channels; i++) {
2938b297 PF	143	ret = i2c_smbus_read_byte_data(client, TMP421_TEMP_MSB[i]);
	144	if (ret < 0)
	145	goto exit;
5e3dbeac	146	data->channel[i].temp = ret << 8;
2938b297 PF	147
	148	ret = i2c_smbus_read_byte_data(client, TMP421_TEMP_LSB[i]);
	149	if (ret < 0)
	150	goto exit;
5e3dbeac	151	data->channel[i].temp \|= ret;
9410700b AP	152	}
9410700b AP	153	data->last_updated = jiffies;
952a11ca	154	data->valid = true;
9410700b AP	155	}
9410700b AP	156
2938b297	157	exit:
9410700b AP	158	mutex_unlock(&data->update_lock);
9410700b AP	159
2938b297	160	if (ret < 0) {
952a11ca	161	data->valid = false;
2938b297 PF	162	return ret;
	163	}
	164
	165	return 0;
9410700b AP	166	}
9410700b AP	167
f3fbf4b8 KA	168	static int tmp421_enable_channels(struct tmp421_data *data)
	169	{
	170	int err;
	171	struct i2c_client *client = data->client;
	172	struct device *dev = &client->dev;
	173	int old = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_2);
	174	int new, i;
	175
	176	if (old < 0) {
	177	dev_err(dev, "error reading register, can't disable channels\n");
	178	return old;
	179	}
	180
	181	new = old & ~TMP421_CONFIG_REG_REN_MASK;
	182	for (i = 0; i < data->channels; i++)
	183	if (data->channel[i].enabled)
	184	new \|= TMP421_CONFIG_REG_REN(i);
	185
	186	if (new == old)
	187	return 0;
	188
	189	err = i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_2, new);
	190	if (err < 0)
	191	dev_err(dev, "error writing register, can't disable channels\n");
	192
	193	return err;
	194	}
	195
bb43cc45 GR	196	static int tmp421_read(struct device *dev, enum hwmon_sensor_types type,
bb43cc45 GR	197	u32 attr, int channel, long *val)
9410700b	198	{
2938b297 PF	199	struct tmp421_data *tmp421 = dev_get_drvdata(dev);
	200	int ret = 0;
	201
	202	ret = tmp421_update_device(tmp421);
	203	if (ret)
	204	return ret;
bb43cc45 GR	205
	206	switch (attr) {
	207	case hwmon_temp_input:
1a98068c KA	208	if (!tmp421->channel[channel].enabled)
1a98068c KA	209	return -ENODATA;
5e3dbeac	210	*val = temp_from_raw(tmp421->channel[channel].temp,
724e8af8	211	tmp421->config & TMP421_CONFIG_RANGE);
bb43cc45 GR	212	return 0;
bb43cc45 GR	213	case hwmon_temp_fault:
1a98068c KA	214	if (!tmp421->channel[channel].enabled)
1a98068c KA	215	return -ENODATA;
bb43cc45	216	/*
540effa7 PF	217	* Any of OPEN or /PVLD bits indicate a hardware mulfunction
540effa7 PF	218	* and the conversion result may be incorrect
bb43cc45	219	*/
5e3dbeac	220	*val = !!(tmp421->channel[channel].temp & 0x03);
bb43cc45	221	return 0;
1a98068c KA	222	case hwmon_temp_enable:
	223	*val = tmp421->channel[channel].enabled;
	224	return 0;
bb43cc45 GR	225	default:
	226	return -EOPNOTSUPP;
	227	}
9410700b	228
9410700b AP	229	}
9410700b AP	230
c1143d1b KA	231	static int tmp421_read_string(struct device *dev, enum hwmon_sensor_types type,
	232	u32 attr, int channel, const char **str)
	233	{
	234	struct tmp421_data *data = dev_get_drvdata(dev);
	235
	236	*str = data->channel[channel].label;
	237
	238	return 0;
	239	}
	240
1a98068c KA	241	static int tmp421_write(struct device *dev, enum hwmon_sensor_types type,
	242	u32 attr, int channel, long val)
	243	{
	244	struct tmp421_data *data = dev_get_drvdata(dev);
	245	int ret;
	246
	247	switch (attr) {
	248	case hwmon_temp_enable:
	249	data->channel[channel].enabled = val;
	250	ret = tmp421_enable_channels(data);
	251	break;
	252	default:
	253	ret = -EOPNOTSUPP;
	254	}
	255
	256	return ret;
	257	}
	258
bb43cc45 GR	259	static umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type,
bb43cc45 GR	260	u32 attr, int channel)
9410700b	261	{
bb43cc45 GR	262	switch (attr) {
bb43cc45 GR	263	case hwmon_temp_fault:
bb43cc45	264	case hwmon_temp_input:
b626eb22	265	return 0444;
c1143d1b KA	266	case hwmon_temp_label:
c1143d1b KA	267	return 0444;
1a98068c KA	268	case hwmon_temp_enable:
1a98068c KA	269	return 0644;
bb43cc45 GR	270	default:
	271	return 0;
	272	}
9410700b AP	273	}
9410700b AP	274
f3fbf4b8	275	static int tmp421_init_client(struct tmp421_data *data)
9410700b AP	276	{
9410700b AP	277	int config, config_orig;
f3fbf4b8	278	struct i2c_client *client = data->client;
9410700b AP	279
	280	/* Set the conversion rate to 2 Hz */
	281	i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05);
	282
	283	/* Start conversions (disable shutdown if necessary) */
	284	config = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
	285	if (config < 0) {
b55f3757 GR	286	dev_err(&client->dev,
b55f3757 GR	287	"Could not read configuration register (%d)\n", config);
010a166a	288	return config;
9410700b AP	289	}
	290
	291	config_orig = config;
	292	config &= ~TMP421_CONFIG_SHUTDOWN;
	293
	294	if (config != config_orig) {
	295	dev_info(&client->dev, "Enable monitoring chip\n");
	296	i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config);
	297	}
	298
f3fbf4b8	299	return tmp421_enable_channels(data);
9410700b AP	300	}
9410700b AP	301
310ec792	302	static int tmp421_detect(struct i2c_client *client,
9410700b AP	303	struct i2c_board_info *info)
9410700b AP	304	{
dbe73c8f	305	enum chips kind;
9410700b	306	struct i2c_adapter *adapter = client->adapter;
8b9bf554 CIK	307	static const char * const names[] = {
	308	"TMP421", "TMP422", "TMP423",
	309	"TMP441", "TMP442"
	310	};
a63ee9d8	311	int addr = client->addr;
dbe73c8f	312	u8 reg;
9410700b AP	313
	314	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
	315	return -ENODEV;
	316
dbe73c8f JD	317	reg = i2c_smbus_read_byte_data(client, TMP421_MANUFACTURER_ID_REG);
	318	if (reg != TMP421_MANUFACTURER_ID)
	319	return -ENODEV;
	320
a63ee9d8 GR	321	reg = i2c_smbus_read_byte_data(client, TMP421_CONVERSION_RATE_REG);
	322	if (reg & 0xf8)
	323	return -ENODEV;
	324
	325	reg = i2c_smbus_read_byte_data(client, TMP421_STATUS_REG);
	326	if (reg & 0x7f)
	327	return -ENODEV;
	328
dbe73c8f JD	329	reg = i2c_smbus_read_byte_data(client, TMP421_DEVICE_ID_REG);
	330	switch (reg) {
	331	case TMP421_DEVICE_ID:
	332	kind = tmp421;
	333	break;
	334	case TMP422_DEVICE_ID:
a63ee9d8 GR	335	if (addr == 0x2a)
a63ee9d8 GR	336	return -ENODEV;
dbe73c8f JD	337	kind = tmp422;
	338	break;
	339	case TMP423_DEVICE_ID:
a63ee9d8 GR	340	if (addr != 0x4c && addr != 0x4d)
a63ee9d8 GR	341	return -ENODEV;
dbe73c8f JD	342	kind = tmp423;
dbe73c8f JD	343	break;
05c77ab2 GR	344	case TMP441_DEVICE_ID:
	345	kind = tmp441;
	346	break;
	347	case TMP442_DEVICE_ID:
	348	if (addr != 0x4c && addr != 0x4d)
	349	return -ENODEV;
	350	kind = tmp442;
	351	break;
dbe73c8f JD	352	default:
dbe73c8f JD	353	return -ENODEV;
9410700b	354	}
dbe73c8f	355
f2f394db	356	strscpy(info->type, tmp421_id[kind].name, I2C_NAME_SIZE);
9410700b	357	dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n",
dc71afe5	358	names[kind], client->addr);
9410700b AP	359
	360	return 0;
	361	}
	362
c1143d1b KA	363	static int tmp421_probe_child_from_dt(struct i2c_client *client,
	364	struct device_node *child,
	365	struct tmp421_data *data)
	366
	367	{
	368	struct device *dev = &client->dev;
	369	u32 i;
3fba10dc	370	s32 val;
c1143d1b KA	371	int err;
	372
	373	err = of_property_read_u32(child, "reg", &i);
	374	if (err) {
	375	dev_err(dev, "missing reg property of %pOFn\n", child);
	376	return err;
	377	}
	378
	379	if (i >= data->channels) {
	380	dev_err(dev, "invalid reg %d of %pOFn\n", i, child);
	381	return -EINVAL;
	382	}
	383
	384	of_property_read_string(child, "label", &data->channel[i].label);
	385	if (data->channel[i].label)
	386	data->temp_config[i] \|= HWMON_T_LABEL;
	387
45e9bda4 KA	388	data->channel[i].enabled = of_device_is_available(child);
45e9bda4 KA	389
3fba10dc KA	390	err = of_property_read_s32(child, "ti,n-factor", &val);
	391	if (!err) {
	392	if (i == 0) {
	393	dev_err(dev, "n-factor can't be set for internal channel\n");
	394	return -EINVAL;
	395	}
	396
	397	if (val > 127 \|\| val < -128) {
	398	dev_err(dev, "n-factor for channel %d invalid (%d)\n",
	399	i, val);
	400	return -EINVAL;
	401	}
	402	i2c_smbus_write_byte_data(client, TMP421_N_FACTOR_REG_1 + i - 1,
	403	val);
	404	}
	405
c1143d1b KA	406	return 0;
	407	}
	408
	409	static int tmp421_probe_from_dt(struct i2c_client client, struct tmp421_data data)
	410	{
	411	struct device *dev = &client->dev;
	412	const struct device_node *np = dev->of_node;
	413	struct device_node *child;
	414	int err;
	415
	416	for_each_child_of_node(np, child) {
3e4dd2e8 KA	417	if (strcmp(child->name, "channel"))
	418	continue;
	419
c1143d1b	420	err = tmp421_probe_child_from_dt(client, child, data);
66ae4d56 WJ	421	if (err) {
66ae4d56 WJ	422	of_node_put(child);
c1143d1b	423	return err;
66ae4d56	424	}
c1143d1b KA	425	}
	426
	427	return 0;
	428	}
	429
bb43cc45 GR	430	static const struct hwmon_ops tmp421_ops = {
	431	.is_visible = tmp421_is_visible,
	432	.read = tmp421_read,
c1143d1b	433	.read_string = tmp421_read_string,
1a98068c	434	.write = tmp421_write,
bb43cc45 GR	435	};
bb43cc45 GR	436
67487038	437	static int tmp421_probe(struct i2c_client *client)
9410700b	438	{
276dac80 GR	439	struct device *dev = &client->dev;
276dac80 GR	440	struct device *hwmon_dev;
9410700b	441	struct tmp421_data *data;
bb43cc45	442	int i, err;
9410700b	443
276dac80	444	data = devm_kzalloc(dev, sizeof(struct tmp421_data), GFP_KERNEL);
9410700b AP	445	if (!data)
	446	return -ENOMEM;
	447
9410700b	448	mutex_init(&data->update_lock);
a1253027 JMC	449	if (client->dev.of_node)
	450	data->channels = (unsigned long)
	451	of_device_get_match_data(&client->dev);
	452	else
67487038	453	data->channels = i2c_match_id(tmp421_id, client)->driver_data;
276dac80	454	data->client = client;
9410700b	455
45e9bda4	456	for (i = 0; i < data->channels; i++) {
1a98068c	457	data->temp_config[i] = HWMON_T_INPUT \| HWMON_T_FAULT \| HWMON_T_ENABLE;
45e9bda4 KA	458	data->channel[i].enabled = true;
45e9bda4 KA	459	}
bb43cc45	460
c1143d1b KA	461	err = tmp421_probe_from_dt(client, data);
	462	if (err)
	463	return err;
	464
f3fbf4b8 KA	465	err = tmp421_init_client(data);
	466	if (err)
	467	return err;
	468
bb43cc45 GR	469	data->chip.ops = &tmp421_ops;
	470	data->chip.info = data->info;
	471
	472	data->info[0] = &data->temp_info;
	473
	474	data->temp_info.type = hwmon_temp;
	475	data->temp_info.config = data->temp_config;
	476
	477	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
	478	data,
	479	&data->chip,
	480	NULL);
276dac80	481	return PTR_ERR_OR_ZERO(hwmon_dev);
9410700b AP	482	}
	483
	484	static struct i2c_driver tmp421_driver = {
	485	.class = I2C_CLASS_HWMON,
	486	.driver = {
	487	.name = "tmp421",
a1253027	488	.of_match_table = of_match_ptr(tmp421_of_match),
9410700b	489	},
1975d167	490	.probe = tmp421_probe,
9410700b AP	491	.id_table = tmp421_id,
9410700b AP	492	.detect = tmp421_detect,
c3813d6a	493	.address_list = normal_i2c,
9410700b AP	494	};
9410700b AP	495
f0967eea	496	module_i2c_driver(tmp421_driver);
9410700b AP	497
9410700b AP	498	MODULE_AUTHOR("Andre Prendel <andre.prendel@gmx.de>");
05c77ab2	499	MODULE_DESCRIPTION("Texas Instruments TMP421/422/423/441/442 temperature sensor driver");
9410700b	500	MODULE_LICENSE("GPL");