1// SPDX-License-Identifier: GPL-2.0-or-later
  2/* Texas Instruments TMP102 SMBus temperature sensor driver
  3 *
  4 * Copyright (C) 2010 Steven King <sfking@fdwdc.com>
 
 
 
 
 
 
 
 
 
 
  5 */
  6
  7#include <linux/delay.h>
  8#include <linux/module.h>
  9#include <linux/init.h>
 10#include <linux/slab.h>
 11#include <linux/i2c.h>
 12#include <linux/hwmon.h>
 13#include <linux/hwmon-sysfs.h>
 14#include <linux/err.h>
 15#include <linux/mutex.h>
 16#include <linux/device.h>
 17#include <linux/jiffies.h>
 18#include <linux/regmap.h>
 19#include <linux/of.h>
 20
 21#define	DRIVER_NAME "tmp102"
 22
 23#define	TMP102_TEMP_REG			0x00
 24#define	TMP102_CONF_REG			0x01
 25/* note: these bit definitions are byte swapped */
 26#define		TMP102_CONF_SD		0x0100
 27#define		TMP102_CONF_TM		0x0200
 28#define		TMP102_CONF_POL		0x0400
 29#define		TMP102_CONF_F0		0x0800
 30#define		TMP102_CONF_F1		0x1000
 31#define		TMP102_CONF_R0		0x2000
 32#define		TMP102_CONF_R1		0x4000
 33#define		TMP102_CONF_OS		0x8000
 34#define		TMP102_CONF_EM		0x0010
 35#define		TMP102_CONF_AL		0x0020
 36#define		TMP102_CONF_CR0		0x0040
 37#define		TMP102_CONF_CR1		0x0080
 38#define	TMP102_TLOW_REG			0x02
 39#define	TMP102_THIGH_REG		0x03
 40
 41#define TMP102_CONFREG_MASK	(TMP102_CONF_SD | TMP102_CONF_TM | \
 42				 TMP102_CONF_POL | TMP102_CONF_F0 | \
 43				 TMP102_CONF_F1 | TMP102_CONF_OS | \
 44				 TMP102_CONF_EM | TMP102_CONF_AL | \
 45				 TMP102_CONF_CR0 | TMP102_CONF_CR1)
 46
 47#define TMP102_CONFIG_CLEAR	(TMP102_CONF_SD | TMP102_CONF_OS | \
 48				 TMP102_CONF_CR0)
 49#define TMP102_CONFIG_SET	(TMP102_CONF_TM | TMP102_CONF_EM | \
 50				 TMP102_CONF_CR1)
 51
 52#define CONVERSION_TIME_MS		35	/* in milli-seconds */
 53
 54struct tmp102 {
 55	struct regmap *regmap;
 56	u16 config_orig;
 57	unsigned long ready_time;
 58};
 59
 60/* convert left adjusted 13-bit TMP102 register value to milliCelsius */
 61static inline int tmp102_reg_to_mC(s16 val)
 62{
 63	return ((val & ~0x01) * 1000) / 128;
 64}
 65
 66/* convert milliCelsius to left adjusted 13-bit TMP102 register value */
 67static inline u16 tmp102_mC_to_reg(int val)
 68{
 69	return (val * 128) / 1000;
 70}
 71
 72static int tmp102_read(struct device *dev, enum hwmon_sensor_types type,
 73		       u32 attr, int channel, long *temp)
 74{
 75	struct tmp102 *tmp102 = dev_get_drvdata(dev);
 76	unsigned int regval;
 77	int err, reg;
 78
 79	switch (attr) {
 80	case hwmon_temp_input:
 81		/* Is it too early to return a conversion ? */
 82		if (time_before(jiffies, tmp102->ready_time)) {
 83			dev_dbg(dev, "%s: Conversion not ready yet..\n", __func__);
 84			return -EAGAIN;
 85		}
 86		reg = TMP102_TEMP_REG;
 87		break;
 88	case hwmon_temp_max_hyst:
 89		reg = TMP102_TLOW_REG;
 90		break;
 91	case hwmon_temp_max:
 92		reg = TMP102_THIGH_REG;
 93		break;
 94	default:
 95		return -EOPNOTSUPP;
 96	}
 97
 98	err = regmap_read(tmp102->regmap, reg, &regval);
 99	if (err < 0)
100		return err;
101	*temp = tmp102_reg_to_mC(regval);
102
103	return 0;
104}
105
106static int tmp102_write(struct device *dev, enum hwmon_sensor_types type,
107			u32 attr, int channel, long temp)
108{
109	struct tmp102 *tmp102 = dev_get_drvdata(dev);
110	int reg;
111
112	switch (attr) {
113	case hwmon_temp_max_hyst:
114		reg = TMP102_TLOW_REG;
115		break;
116	case hwmon_temp_max:
117		reg = TMP102_THIGH_REG;
118		break;
119	default:
120		return -EOPNOTSUPP;
121	}
122
123	temp = clamp_val(temp, -256000, 255000);
124	return regmap_write(tmp102->regmap, reg, tmp102_mC_to_reg(temp));
125}
126
127static umode_t tmp102_is_visible(const void *data, enum hwmon_sensor_types type,
128				 u32 attr, int channel)
129{
130	if (type != hwmon_temp)
131		return 0;
132
133	switch (attr) {
134	case hwmon_temp_input:
135		return 0444;
136	case hwmon_temp_max_hyst:
137	case hwmon_temp_max:
138		return 0644;
139	default:
140		return 0;
141	}
142}
143
144static const struct hwmon_channel_info * const tmp102_info[] = {
145	HWMON_CHANNEL_INFO(chip,
146			   HWMON_C_REGISTER_TZ),
147	HWMON_CHANNEL_INFO(temp,
148			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST),
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
149	NULL
150};
151
152static const struct hwmon_ops tmp102_hwmon_ops = {
153	.is_visible = tmp102_is_visible,
154	.read = tmp102_read,
155	.write = tmp102_write,
156};
157
158static const struct hwmon_chip_info tmp102_chip_info = {
159	.ops = &tmp102_hwmon_ops,
160	.info = tmp102_info,
161};
162
163static void tmp102_restore_config(void *data)
164{
165	struct tmp102 *tmp102 = data;
166
167	regmap_write(tmp102->regmap, TMP102_CONF_REG, tmp102->config_orig);
168}
169
170static bool tmp102_is_writeable_reg(struct device *dev, unsigned int reg)
171{
172	return reg != TMP102_TEMP_REG;
173}
174
175static bool tmp102_is_volatile_reg(struct device *dev, unsigned int reg)
176{
177	return reg == TMP102_TEMP_REG;
178}
179
180static const struct regmap_config tmp102_regmap_config = {
181	.reg_bits = 8,
182	.val_bits = 16,
183	.max_register = TMP102_THIGH_REG,
184	.writeable_reg = tmp102_is_writeable_reg,
185	.volatile_reg = tmp102_is_volatile_reg,
186	.val_format_endian = REGMAP_ENDIAN_BIG,
187	.cache_type = REGCACHE_MAPLE,
188	.use_single_read = true,
189	.use_single_write = true,
190};
191
192static int tmp102_probe(struct i2c_client *client)
 
193{
194	struct device *dev = &client->dev;
195	struct device *hwmon_dev;
196	struct tmp102 *tmp102;
197	unsigned int regval;
198	int err;
199
200	if (!i2c_check_functionality(client->adapter,
201				     I2C_FUNC_SMBUS_WORD_DATA)) {
202		dev_err(dev,
203			"adapter doesn't support SMBus word transactions\n");
204		return -ENODEV;
205	}
206
207	tmp102 = devm_kzalloc(dev, sizeof(*tmp102), GFP_KERNEL);
208	if (!tmp102)
209		return -ENOMEM;
210
211	i2c_set_clientdata(client, tmp102);
212
213	tmp102->regmap = devm_regmap_init_i2c(client, &tmp102_regmap_config);
214	if (IS_ERR(tmp102->regmap))
215		return PTR_ERR(tmp102->regmap);
216
217	err = regmap_read(tmp102->regmap, TMP102_CONF_REG, &regval);
218	if (err < 0) {
219		dev_err(dev, "error reading config register\n");
220		return err;
221	}
222
223	if ((regval & ~TMP102_CONFREG_MASK) !=
224	    (TMP102_CONF_R0 | TMP102_CONF_R1)) {
225		dev_err(dev, "unexpected config register value\n");
226		return -ENODEV;
227	}
228
229	tmp102->config_orig = regval;
230
231	err = devm_add_action_or_reset(dev, tmp102_restore_config, tmp102);
232	if (err)
233		return err;
234
235	regval &= ~TMP102_CONFIG_CLEAR;
236	regval |= TMP102_CONFIG_SET;
237
238	err = regmap_write(tmp102->regmap, TMP102_CONF_REG, regval);
239	if (err < 0) {
240		dev_err(dev, "error writing config register\n");
241		return err;
242	}
243
244	/*
245	 * Mark that we are not ready with data until the first
246	 * conversion is complete
247	 */
248	tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
 
 
 
249
250	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
251							 tmp102,
252							 &tmp102_chip_info,
253							 NULL);
254	if (IS_ERR(hwmon_dev)) {
255		dev_dbg(dev, "unable to register hwmon device\n");
256		return PTR_ERR(hwmon_dev);
257	}
258	dev_info(dev, "initialized\n");
259
260	return 0;
261}
262
 
263static int tmp102_suspend(struct device *dev)
264{
265	struct i2c_client *client = to_i2c_client(dev);
266	struct tmp102 *tmp102 = i2c_get_clientdata(client);
267
268	return regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
269				  TMP102_CONF_SD, TMP102_CONF_SD);
270}
271
272static int tmp102_resume(struct device *dev)
273{
274	struct i2c_client *client = to_i2c_client(dev);
275	struct tmp102 *tmp102 = i2c_get_clientdata(client);
276	int err;
277
278	err = regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
279				 TMP102_CONF_SD, 0);
280
281	tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
282
283	return err;
284}
 
285
286static DEFINE_SIMPLE_DEV_PM_OPS(tmp102_dev_pm_ops, tmp102_suspend, tmp102_resume);
287
288static const struct i2c_device_id tmp102_id[] = {
289	{ "tmp102", 0 },
290	{ }
291};
292MODULE_DEVICE_TABLE(i2c, tmp102_id);
293
294static const struct of_device_id __maybe_unused tmp102_of_match[] = {
295	{ .compatible = "ti,tmp102" },
296	{ },
297};
298MODULE_DEVICE_TABLE(of, tmp102_of_match);
299
300static struct i2c_driver tmp102_driver = {
301	.driver.name	= DRIVER_NAME,
302	.driver.of_match_table = of_match_ptr(tmp102_of_match),
303	.driver.pm	= pm_sleep_ptr(&tmp102_dev_pm_ops),
304	.probe		= tmp102_probe,
305	.id_table	= tmp102_id,
306};
307
308module_i2c_driver(tmp102_driver);
309
310MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
311MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
312MODULE_LICENSE("GPL");

 
  1/* Texas Instruments TMP102 SMBus temperature sensor driver
  2 *
  3 * Copyright (C) 2010 Steven King <sfking@fdwdc.com>
  4 *
  5 * This program is free software; you can redistribute it and/or modify
  6 * it under the terms of the GNU General Public License as published by
  7 * the Free Software Foundation; either version 2 of the License, or
  8 * (at your option) any later version.
  9 *
 10 * This program is distributed in the hope that it will be useful,
 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 13 * GNU General Public License for more details.
 14 */
 15
 16#include <linux/delay.h>
 17#include <linux/module.h>
 18#include <linux/init.h>
 19#include <linux/slab.h>
 20#include <linux/i2c.h>
 21#include <linux/hwmon.h>
 22#include <linux/hwmon-sysfs.h>
 23#include <linux/err.h>
 24#include <linux/mutex.h>
 25#include <linux/device.h>
 26#include <linux/jiffies.h>
 27#include <linux/regmap.h>
 28#include <linux/of.h>
 29
 30#define	DRIVER_NAME "tmp102"
 31
 32#define	TMP102_TEMP_REG			0x00
 33#define	TMP102_CONF_REG			0x01
 34/* note: these bit definitions are byte swapped */
 35#define		TMP102_CONF_SD		0x0100
 36#define		TMP102_CONF_TM		0x0200
 37#define		TMP102_CONF_POL		0x0400
 38#define		TMP102_CONF_F0		0x0800
 39#define		TMP102_CONF_F1		0x1000
 40#define		TMP102_CONF_R0		0x2000
 41#define		TMP102_CONF_R1		0x4000
 42#define		TMP102_CONF_OS		0x8000
 43#define		TMP102_CONF_EM		0x0010
 44#define		TMP102_CONF_AL		0x0020
 45#define		TMP102_CONF_CR0		0x0040
 46#define		TMP102_CONF_CR1		0x0080
 47#define	TMP102_TLOW_REG			0x02
 48#define	TMP102_THIGH_REG		0x03
 49
 50#define TMP102_CONFREG_MASK	(TMP102_CONF_SD | TMP102_CONF_TM | \
 51				 TMP102_CONF_POL | TMP102_CONF_F0 | \
 52				 TMP102_CONF_F1 | TMP102_CONF_OS | \
 53				 TMP102_CONF_EM | TMP102_CONF_AL | \
 54				 TMP102_CONF_CR0 | TMP102_CONF_CR1)
 55
 56#define TMP102_CONFIG_CLEAR	(TMP102_CONF_SD | TMP102_CONF_OS | \
 57				 TMP102_CONF_CR0)
 58#define TMP102_CONFIG_SET	(TMP102_CONF_TM | TMP102_CONF_EM | \
 59				 TMP102_CONF_CR1)
 60
 61#define CONVERSION_TIME_MS		35	/* in milli-seconds */
 62
 63struct tmp102 {
 64	struct regmap *regmap;
 65	u16 config_orig;
 66	unsigned long ready_time;
 67};
 68
 69/* convert left adjusted 13-bit TMP102 register value to milliCelsius */
 70static inline int tmp102_reg_to_mC(s16 val)
 71{
 72	return ((val & ~0x01) * 1000) / 128;
 73}
 74
 75/* convert milliCelsius to left adjusted 13-bit TMP102 register value */
 76static inline u16 tmp102_mC_to_reg(int val)
 77{
 78	return (val * 128) / 1000;
 79}
 80
 81static int tmp102_read(struct device *dev, enum hwmon_sensor_types type,
 82		       u32 attr, int channel, long *temp)
 83{
 84	struct tmp102 *tmp102 = dev_get_drvdata(dev);
 85	unsigned int regval;
 86	int err, reg;
 87
 88	switch (attr) {
 89	case hwmon_temp_input:
 90		/* Is it too early to return a conversion ? */
 91		if (time_before(jiffies, tmp102->ready_time)) {
 92			dev_dbg(dev, "%s: Conversion not ready yet..\n", __func__);
 93			return -EAGAIN;
 94		}
 95		reg = TMP102_TEMP_REG;
 96		break;
 97	case hwmon_temp_max_hyst:
 98		reg = TMP102_TLOW_REG;
 99		break;
100	case hwmon_temp_max:
101		reg = TMP102_THIGH_REG;
102		break;
103	default:
104		return -EOPNOTSUPP;
105	}
106
107	err = regmap_read(tmp102->regmap, reg, &regval);
108	if (err < 0)
109		return err;
110	*temp = tmp102_reg_to_mC(regval);
111
112	return 0;
113}
114
115static int tmp102_write(struct device *dev, enum hwmon_sensor_types type,
116			u32 attr, int channel, long temp)
117{
118	struct tmp102 *tmp102 = dev_get_drvdata(dev);
119	int reg;
120
121	switch (attr) {
122	case hwmon_temp_max_hyst:
123		reg = TMP102_TLOW_REG;
124		break;
125	case hwmon_temp_max:
126		reg = TMP102_THIGH_REG;
127		break;
128	default:
129		return -EOPNOTSUPP;
130	}
131
132	temp = clamp_val(temp, -256000, 255000);
133	return regmap_write(tmp102->regmap, reg, tmp102_mC_to_reg(temp));
134}
135
136static umode_t tmp102_is_visible(const void *data, enum hwmon_sensor_types type,
137				 u32 attr, int channel)
138{
139	if (type != hwmon_temp)
140		return 0;
141
142	switch (attr) {
143	case hwmon_temp_input:
144		return S_IRUGO;
145	case hwmon_temp_max_hyst:
146	case hwmon_temp_max:
147		return S_IRUGO | S_IWUSR;
148	default:
149		return 0;
150	}
151}
152
153static u32 tmp102_chip_config[] = {
154	HWMON_C_REGISTER_TZ,
155	0
156};
157
158static const struct hwmon_channel_info tmp102_chip = {
159	.type = hwmon_chip,
160	.config = tmp102_chip_config,
161};
162
163static u32 tmp102_temp_config[] = {
164	HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST,
165	0
166};
167
168static const struct hwmon_channel_info tmp102_temp = {
169	.type = hwmon_temp,
170	.config = tmp102_temp_config,
171};
172
173static const struct hwmon_channel_info *tmp102_info[] = {
174	&tmp102_chip,
175	&tmp102_temp,
176	NULL
177};
178
179static const struct hwmon_ops tmp102_hwmon_ops = {
180	.is_visible = tmp102_is_visible,
181	.read = tmp102_read,
182	.write = tmp102_write,
183};
184
185static const struct hwmon_chip_info tmp102_chip_info = {
186	.ops = &tmp102_hwmon_ops,
187	.info = tmp102_info,
188};
189
190static void tmp102_restore_config(void *data)
191{
192	struct tmp102 *tmp102 = data;
193
194	regmap_write(tmp102->regmap, TMP102_CONF_REG, tmp102->config_orig);
195}
196
197static bool tmp102_is_writeable_reg(struct device *dev, unsigned int reg)
198{
199	return reg != TMP102_TEMP_REG;
200}
201
202static bool tmp102_is_volatile_reg(struct device *dev, unsigned int reg)
203{
204	return reg == TMP102_TEMP_REG;
205}
206
207static const struct regmap_config tmp102_regmap_config = {
208	.reg_bits = 8,
209	.val_bits = 16,
210	.max_register = TMP102_THIGH_REG,
211	.writeable_reg = tmp102_is_writeable_reg,
212	.volatile_reg = tmp102_is_volatile_reg,
213	.val_format_endian = REGMAP_ENDIAN_BIG,
214	.cache_type = REGCACHE_RBTREE,
215	.use_single_rw = true,
 
216};
217
218static int tmp102_probe(struct i2c_client *client,
219			const struct i2c_device_id *id)
220{
221	struct device *dev = &client->dev;
222	struct device *hwmon_dev;
223	struct tmp102 *tmp102;
224	unsigned int regval;
225	int err;
226
227	if (!i2c_check_functionality(client->adapter,
228				     I2C_FUNC_SMBUS_WORD_DATA)) {
229		dev_err(dev,
230			"adapter doesn't support SMBus word transactions\n");
231		return -ENODEV;
232	}
233
234	tmp102 = devm_kzalloc(dev, sizeof(*tmp102), GFP_KERNEL);
235	if (!tmp102)
236		return -ENOMEM;
237
238	i2c_set_clientdata(client, tmp102);
239
240	tmp102->regmap = devm_regmap_init_i2c(client, &tmp102_regmap_config);
241	if (IS_ERR(tmp102->regmap))
242		return PTR_ERR(tmp102->regmap);
243
244	err = regmap_read(tmp102->regmap, TMP102_CONF_REG, &regval);
245	if (err < 0) {
246		dev_err(dev, "error reading config register\n");
247		return err;
248	}
249
250	if ((regval & ~TMP102_CONFREG_MASK) !=
251	    (TMP102_CONF_R0 | TMP102_CONF_R1)) {
252		dev_err(dev, "unexpected config register value\n");
253		return -ENODEV;
254	}
255
256	tmp102->config_orig = regval;
257
258	err = devm_add_action_or_reset(dev, tmp102_restore_config, tmp102);
259	if (err)
260		return err;
261
262	regval &= ~TMP102_CONFIG_CLEAR;
263	regval |= TMP102_CONFIG_SET;
264
265	err = regmap_write(tmp102->regmap, TMP102_CONF_REG, regval);
266	if (err < 0) {
267		dev_err(dev, "error writing config register\n");
268		return err;
269	}
270
271	tmp102->ready_time = jiffies;
272	if (tmp102->config_orig & TMP102_CONF_SD) {
273		/*
274		 * Mark that we are not ready with data until the first
275		 * conversion is complete
276		 */
277		tmp102->ready_time += msecs_to_jiffies(CONVERSION_TIME_MS);
278	}
279
280	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
281							 tmp102,
282							 &tmp102_chip_info,
283							 NULL);
284	if (IS_ERR(hwmon_dev)) {
285		dev_dbg(dev, "unable to register hwmon device\n");
286		return PTR_ERR(hwmon_dev);
287	}
288	dev_info(dev, "initialized\n");
289
290	return 0;
291}
292
293#ifdef CONFIG_PM_SLEEP
294static int tmp102_suspend(struct device *dev)
295{
296	struct i2c_client *client = to_i2c_client(dev);
297	struct tmp102 *tmp102 = i2c_get_clientdata(client);
298
299	return regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
300				  TMP102_CONF_SD, TMP102_CONF_SD);
301}
302
303static int tmp102_resume(struct device *dev)
304{
305	struct i2c_client *client = to_i2c_client(dev);
306	struct tmp102 *tmp102 = i2c_get_clientdata(client);
307	int err;
308
309	err = regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
310				 TMP102_CONF_SD, 0);
311
312	tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
313
314	return err;
315}
316#endif /* CONFIG_PM */
317
318static SIMPLE_DEV_PM_OPS(tmp102_dev_pm_ops, tmp102_suspend, tmp102_resume);
319
320static const struct i2c_device_id tmp102_id[] = {
321	{ "tmp102", 0 },
322	{ }
323};
324MODULE_DEVICE_TABLE(i2c, tmp102_id);
325
 
 
 
 
 
 
326static struct i2c_driver tmp102_driver = {
327	.driver.name	= DRIVER_NAME,
328	.driver.pm	= &tmp102_dev_pm_ops,
 
329	.probe		= tmp102_probe,
330	.id_table	= tmp102_id,
331};
332
333module_i2c_driver(tmp102_driver);
334
335MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
336MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
337MODULE_LICENSE("GPL");