xref: /openbmc/linux/drivers/hwmon/emc1403.c (revision 8e9356c6)
1 /*
2  * emc1403.c - SMSC Thermal Driver
3  *
4  * Copyright (C) 2008 Intel Corp
5  *
6  *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; version 2 of the License.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License along
18  * with this program; if not, write to the Free Software Foundation, Inc.,
19  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
20  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
21  *
22  * TODO
23  *	-	cache alarm and critical limit registers
24  */
25 
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/i2c.h>
30 #include <linux/hwmon.h>
31 #include <linux/hwmon-sysfs.h>
32 #include <linux/err.h>
33 #include <linux/sysfs.h>
34 #include <linux/mutex.h>
35 #include <linux/jiffies.h>
36 
37 #define THERMAL_PID_REG		0xfd
38 #define THERMAL_SMSC_ID_REG	0xfe
39 #define THERMAL_REVISION_REG	0xff
40 
41 struct thermal_data {
42 	struct i2c_client *client;
43 	const struct attribute_group *groups[3];
44 	struct mutex mutex;
45 	/*
46 	 * Cache the hyst value so we don't keep re-reading it. In theory
47 	 * we could cache it forever as nobody else should be writing it.
48 	 */
49 	u8 cached_hyst;
50 	unsigned long hyst_valid;
51 };
52 
53 static ssize_t show_temp(struct device *dev,
54 			struct device_attribute *attr, char *buf)
55 {
56 	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
57 	struct thermal_data *data = dev_get_drvdata(dev);
58 	int retval;
59 
60 	retval = i2c_smbus_read_byte_data(data->client, sda->index);
61 	if (retval < 0)
62 		return retval;
63 	return sprintf(buf, "%d000\n", retval);
64 }
65 
66 static ssize_t show_bit(struct device *dev,
67 			struct device_attribute *attr, char *buf)
68 {
69 	struct sensor_device_attribute_2 *sda = to_sensor_dev_attr_2(attr);
70 	struct thermal_data *data = dev_get_drvdata(dev);
71 	int retval;
72 
73 	retval = i2c_smbus_read_byte_data(data->client, sda->nr);
74 	if (retval < 0)
75 		return retval;
76 	return sprintf(buf, "%d\n", !!(retval & sda->index));
77 }
78 
79 static ssize_t store_temp(struct device *dev,
80 		struct device_attribute *attr, const char *buf, size_t count)
81 {
82 	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
83 	struct thermal_data *data = dev_get_drvdata(dev);
84 	unsigned long val;
85 	int retval;
86 
87 	if (kstrtoul(buf, 10, &val))
88 		return -EINVAL;
89 	retval = i2c_smbus_write_byte_data(data->client, sda->index,
90 					DIV_ROUND_CLOSEST(val, 1000));
91 	if (retval < 0)
92 		return retval;
93 	return count;
94 }
95 
96 static ssize_t store_bit(struct device *dev,
97 		struct device_attribute *attr, const char *buf, size_t count)
98 {
99 	struct sensor_device_attribute_2 *sda = to_sensor_dev_attr_2(attr);
100 	struct thermal_data *data = dev_get_drvdata(dev);
101 	struct i2c_client *client = data->client;
102 	unsigned long val;
103 	int retval;
104 
105 	if (kstrtoul(buf, 10, &val))
106 		return -EINVAL;
107 
108 	mutex_lock(&data->mutex);
109 	retval = i2c_smbus_read_byte_data(client, sda->nr);
110 	if (retval < 0)
111 		goto fail;
112 
113 	retval &= ~sda->index;
114 	if (val)
115 		retval |= sda->index;
116 
117 	retval = i2c_smbus_write_byte_data(client, sda->index, retval);
118 	if (retval == 0)
119 		retval = count;
120 fail:
121 	mutex_unlock(&data->mutex);
122 	return retval;
123 }
124 
125 static ssize_t show_hyst(struct device *dev,
126 			struct device_attribute *attr, char *buf)
127 {
128 	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
129 	struct thermal_data *data = dev_get_drvdata(dev);
130 	struct i2c_client *client = data->client;
131 	int retval;
132 	int hyst;
133 
134 	retval = i2c_smbus_read_byte_data(client, sda->index);
135 	if (retval < 0)
136 		return retval;
137 
138 	if (time_after(jiffies, data->hyst_valid)) {
139 		hyst = i2c_smbus_read_byte_data(client, 0x21);
140 		if (hyst < 0)
141 			return retval;
142 		data->cached_hyst = hyst;
143 		data->hyst_valid = jiffies + HZ;
144 	}
145 	return sprintf(buf, "%d000\n", retval - data->cached_hyst);
146 }
147 
148 static ssize_t store_hyst(struct device *dev,
149 		struct device_attribute *attr, const char *buf, size_t count)
150 {
151 	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
152 	struct thermal_data *data = dev_get_drvdata(dev);
153 	struct i2c_client *client = data->client;
154 	int retval;
155 	int hyst;
156 	unsigned long val;
157 
158 	if (kstrtoul(buf, 10, &val))
159 		return -EINVAL;
160 
161 	mutex_lock(&data->mutex);
162 	retval = i2c_smbus_read_byte_data(client, sda->index);
163 	if (retval < 0)
164 		goto fail;
165 
166 	hyst = val - retval * 1000;
167 	hyst = DIV_ROUND_CLOSEST(hyst, 1000);
168 	if (hyst < 0 || hyst > 255) {
169 		retval = -ERANGE;
170 		goto fail;
171 	}
172 
173 	retval = i2c_smbus_write_byte_data(client, 0x21, hyst);
174 	if (retval == 0) {
175 		retval = count;
176 		data->cached_hyst = hyst;
177 		data->hyst_valid = jiffies + HZ;
178 	}
179 fail:
180 	mutex_unlock(&data->mutex);
181 	return retval;
182 }
183 
184 /*
185  *	Sensors. We pass the actual i2c register to the methods.
186  */
187 
188 static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO | S_IWUSR,
189 	show_temp, store_temp, 0x06);
190 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR,
191 	show_temp, store_temp, 0x05);
192 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO | S_IWUSR,
193 	show_temp, store_temp, 0x20);
194 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0x00);
195 static SENSOR_DEVICE_ATTR_2(temp1_min_alarm, S_IRUGO,
196 	show_bit, NULL, 0x36, 0x01);
197 static SENSOR_DEVICE_ATTR_2(temp1_max_alarm, S_IRUGO,
198 	show_bit, NULL, 0x35, 0x01);
199 static SENSOR_DEVICE_ATTR_2(temp1_crit_alarm, S_IRUGO,
200 	show_bit, NULL, 0x37, 0x01);
201 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO | S_IWUSR,
202 	show_hyst, store_hyst, 0x20);
203 
204 static SENSOR_DEVICE_ATTR(temp2_min, S_IRUGO | S_IWUSR,
205 	show_temp, store_temp, 0x08);
206 static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO | S_IWUSR,
207 	show_temp, store_temp, 0x07);
208 static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO | S_IWUSR,
209 	show_temp, store_temp, 0x19);
210 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 0x01);
211 static SENSOR_DEVICE_ATTR_2(temp2_min_alarm, S_IRUGO,
212 	show_bit, NULL, 0x36, 0x02);
213 static SENSOR_DEVICE_ATTR_2(temp2_max_alarm, S_IRUGO,
214 	show_bit, NULL, 0x35, 0x02);
215 static SENSOR_DEVICE_ATTR_2(temp2_crit_alarm, S_IRUGO,
216 	show_bit, NULL, 0x37, 0x02);
217 static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IRUGO | S_IWUSR,
218 	show_hyst, store_hyst, 0x19);
219 
220 static SENSOR_DEVICE_ATTR(temp3_min, S_IRUGO | S_IWUSR,
221 	show_temp, store_temp, 0x16);
222 static SENSOR_DEVICE_ATTR(temp3_max, S_IRUGO | S_IWUSR,
223 	show_temp, store_temp, 0x15);
224 static SENSOR_DEVICE_ATTR(temp3_crit, S_IRUGO | S_IWUSR,
225 	show_temp, store_temp, 0x1A);
226 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 0x23);
227 static SENSOR_DEVICE_ATTR_2(temp3_min_alarm, S_IRUGO,
228 	show_bit, NULL, 0x36, 0x04);
229 static SENSOR_DEVICE_ATTR_2(temp3_max_alarm, S_IRUGO,
230 	show_bit, NULL, 0x35, 0x04);
231 static SENSOR_DEVICE_ATTR_2(temp3_crit_alarm, S_IRUGO,
232 	show_bit, NULL, 0x37, 0x04);
233 static SENSOR_DEVICE_ATTR(temp3_crit_hyst, S_IRUGO | S_IWUSR,
234 	show_hyst, store_hyst, 0x1A);
235 
236 static SENSOR_DEVICE_ATTR(temp4_min, S_IRUGO | S_IWUSR,
237 	show_temp, store_temp, 0x2D);
238 static SENSOR_DEVICE_ATTR(temp4_max, S_IRUGO | S_IWUSR,
239 	show_temp, store_temp, 0x2C);
240 static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO | S_IWUSR,
241 	show_temp, store_temp, 0x30);
242 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 0x2A);
243 static SENSOR_DEVICE_ATTR_2(temp4_min_alarm, S_IRUGO,
244 	show_bit, NULL, 0x36, 0x08);
245 static SENSOR_DEVICE_ATTR_2(temp4_max_alarm, S_IRUGO,
246 	show_bit, NULL, 0x35, 0x08);
247 static SENSOR_DEVICE_ATTR_2(temp4_crit_alarm, S_IRUGO,
248 	show_bit, NULL, 0x37, 0x08);
249 static SENSOR_DEVICE_ATTR(temp4_crit_hyst, S_IRUGO | S_IWUSR,
250 	show_hyst, store_hyst, 0x30);
251 
252 static SENSOR_DEVICE_ATTR_2(power_state, S_IRUGO | S_IWUSR,
253 	show_bit, store_bit, 0x03, 0x40);
254 
255 static struct attribute *emc1403_attrs[] = {
256 	&sensor_dev_attr_temp1_min.dev_attr.attr,
257 	&sensor_dev_attr_temp1_max.dev_attr.attr,
258 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
259 	&sensor_dev_attr_temp1_input.dev_attr.attr,
260 	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
261 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
262 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
263 	&sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
264 	&sensor_dev_attr_temp2_min.dev_attr.attr,
265 	&sensor_dev_attr_temp2_max.dev_attr.attr,
266 	&sensor_dev_attr_temp2_crit.dev_attr.attr,
267 	&sensor_dev_attr_temp2_input.dev_attr.attr,
268 	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
269 	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
270 	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
271 	&sensor_dev_attr_temp2_crit_hyst.dev_attr.attr,
272 	&sensor_dev_attr_temp3_min.dev_attr.attr,
273 	&sensor_dev_attr_temp3_max.dev_attr.attr,
274 	&sensor_dev_attr_temp3_crit.dev_attr.attr,
275 	&sensor_dev_attr_temp3_input.dev_attr.attr,
276 	&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
277 	&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
278 	&sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
279 	&sensor_dev_attr_temp3_crit_hyst.dev_attr.attr,
280 	&sensor_dev_attr_power_state.dev_attr.attr,
281 	NULL
282 };
283 
284 static const struct attribute_group emc1403_group = {
285 	.attrs = emc1403_attrs,
286 };
287 
288 static struct attribute *emc1404_attrs[] = {
289 	&sensor_dev_attr_temp4_min.dev_attr.attr,
290 	&sensor_dev_attr_temp4_max.dev_attr.attr,
291 	&sensor_dev_attr_temp4_crit.dev_attr.attr,
292 	&sensor_dev_attr_temp4_input.dev_attr.attr,
293 	&sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
294 	&sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
295 	&sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
296 	&sensor_dev_attr_temp4_crit_hyst.dev_attr.attr,
297 	NULL
298 };
299 
300 static const struct attribute_group emc1404_group = {
301 	.attrs = emc1404_attrs,
302 };
303 
304 static int emc1403_detect(struct i2c_client *client,
305 			struct i2c_board_info *info)
306 {
307 	int id;
308 	/* Check if thermal chip is SMSC and EMC1403 or EMC1423 */
309 
310 	id = i2c_smbus_read_byte_data(client, THERMAL_SMSC_ID_REG);
311 	if (id != 0x5d)
312 		return -ENODEV;
313 
314 	id = i2c_smbus_read_byte_data(client, THERMAL_PID_REG);
315 	switch (id) {
316 	case 0x21:
317 		strlcpy(info->type, "emc1403", I2C_NAME_SIZE);
318 		break;
319 	case 0x23:
320 		strlcpy(info->type, "emc1423", I2C_NAME_SIZE);
321 		break;
322 	case 0x25:
323 		strlcpy(info->type, "emc1404", I2C_NAME_SIZE);
324 		break;
325 	case 0x27:
326 		strlcpy(info->type, "emc1424", I2C_NAME_SIZE);
327 		break;
328 	default:
329 		return -ENODEV;
330 	}
331 
332 	id = i2c_smbus_read_byte_data(client, THERMAL_REVISION_REG);
333 	if (id != 0x01)
334 		return -ENODEV;
335 
336 	return 0;
337 }
338 
339 static int emc1403_probe(struct i2c_client *client,
340 			const struct i2c_device_id *id)
341 {
342 	struct thermal_data *data;
343 	struct device *hwmon_dev;
344 
345 	data = devm_kzalloc(&client->dev, sizeof(struct thermal_data),
346 			    GFP_KERNEL);
347 	if (data == NULL)
348 		return -ENOMEM;
349 
350 	data->client = client;
351 	mutex_init(&data->mutex);
352 	data->hyst_valid = jiffies - 1;		/* Expired */
353 
354 	data->groups[0] = &emc1403_group;
355 	if (id->driver_data)
356 		data->groups[1] = &emc1404_group;
357 
358 	hwmon_dev = hwmon_device_register_with_groups(&client->dev,
359 						      client->name, data,
360 						      data->groups);
361 	if (IS_ERR(hwmon_dev))
362 		return PTR_ERR(hwmon_dev);
363 
364 	dev_info(&client->dev, "%s Thermal chip found\n", id->name);
365 	return 0;
366 }
367 
368 static const unsigned short emc1403_address_list[] = {
369 	0x18, 0x29, 0x4c, 0x4d, I2C_CLIENT_END
370 };
371 
372 static const struct i2c_device_id emc1403_idtable[] = {
373 	{ "emc1403", 0 },
374 	{ "emc1404", 1 },
375 	{ "emc1423", 0 },
376 	{ "emc1424", 1 },
377 	{ }
378 };
379 MODULE_DEVICE_TABLE(i2c, emc1403_idtable);
380 
381 static struct i2c_driver sensor_emc1403 = {
382 	.class = I2C_CLASS_HWMON,
383 	.driver = {
384 		.name = "emc1403",
385 	},
386 	.detect = emc1403_detect,
387 	.probe = emc1403_probe,
388 	.id_table = emc1403_idtable,
389 	.address_list = emc1403_address_list,
390 };
391 
392 module_i2c_driver(sensor_emc1403);
393 
394 MODULE_AUTHOR("Kalhan Trisal <kalhan.trisal@intel.com");
395 MODULE_DESCRIPTION("emc1403 Thermal Driver");
396 MODULE_LICENSE("GPL v2");
397