xref: /openbmc/linux/drivers/hwmon/sch5627.c (revision 3d37ef41)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /***************************************************************************
3  *   Copyright (C) 2010-2012 Hans de Goede <hdegoede@redhat.com>           *
4  *                                                                         *
5  ***************************************************************************/
6 
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8 
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/slab.h>
12 #include <linux/jiffies.h>
13 #include <linux/platform_device.h>
14 #include <linux/hwmon.h>
15 #include <linux/err.h>
16 #include <linux/mutex.h>
17 #include "sch56xx-common.h"
18 
19 #define DRVNAME "sch5627"
20 #define DEVNAME DRVNAME /* We only support one model */
21 
22 #define SCH5627_HWMON_ID		0xa5
23 #define SCH5627_COMPANY_ID		0x5c
24 #define SCH5627_PRIMARY_ID		0xa0
25 
26 #define SCH5627_REG_BUILD_CODE		0x39
27 #define SCH5627_REG_BUILD_ID		0x3a
28 #define SCH5627_REG_HWMON_ID		0x3c
29 #define SCH5627_REG_HWMON_REV		0x3d
30 #define SCH5627_REG_COMPANY_ID		0x3e
31 #define SCH5627_REG_PRIMARY_ID		0x3f
32 #define SCH5627_REG_CTRL		0x40
33 
34 #define SCH5627_NO_TEMPS		8
35 #define SCH5627_NO_FANS			4
36 #define SCH5627_NO_IN			5
37 
38 static const u16 SCH5627_REG_TEMP_MSB[SCH5627_NO_TEMPS] = {
39 	0x2B, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x180, 0x181 };
40 static const u16 SCH5627_REG_TEMP_LSN[SCH5627_NO_TEMPS] = {
41 	0xE2, 0xE1, 0xE1, 0xE5, 0xE5, 0xE6, 0x182, 0x182 };
42 static const u16 SCH5627_REG_TEMP_HIGH_NIBBLE[SCH5627_NO_TEMPS] = {
43 	0, 0, 1, 1, 0, 0, 0, 1 };
44 static const u16 SCH5627_REG_TEMP_HIGH[SCH5627_NO_TEMPS] = {
45 	0x61, 0x57, 0x59, 0x5B, 0x5D, 0x5F, 0x184, 0x186 };
46 static const u16 SCH5627_REG_TEMP_ABS[SCH5627_NO_TEMPS] = {
47 	0x9B, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x1A8, 0x1A9 };
48 
49 static const u16 SCH5627_REG_FAN[SCH5627_NO_FANS] = {
50 	0x2C, 0x2E, 0x30, 0x32 };
51 static const u16 SCH5627_REG_FAN_MIN[SCH5627_NO_FANS] = {
52 	0x62, 0x64, 0x66, 0x68 };
53 
54 static const u16 SCH5627_REG_IN_MSB[SCH5627_NO_IN] = {
55 	0x22, 0x23, 0x24, 0x25, 0x189 };
56 static const u16 SCH5627_REG_IN_LSN[SCH5627_NO_IN] = {
57 	0xE4, 0xE4, 0xE3, 0xE3, 0x18A };
58 static const u16 SCH5627_REG_IN_HIGH_NIBBLE[SCH5627_NO_IN] = {
59 	1, 0, 1, 0, 1 };
60 static const u16 SCH5627_REG_IN_FACTOR[SCH5627_NO_IN] = {
61 	10745, 3660, 9765, 10745, 3660 };
62 static const char * const SCH5627_IN_LABELS[SCH5627_NO_IN] = {
63 	"VCC", "VTT", "VBAT", "VTR", "V_IN" };
64 
65 struct sch5627_data {
66 	unsigned short addr;
67 	struct sch56xx_watchdog_data *watchdog;
68 	u8 control;
69 	u8 temp_max[SCH5627_NO_TEMPS];
70 	u8 temp_crit[SCH5627_NO_TEMPS];
71 	u16 fan_min[SCH5627_NO_FANS];
72 
73 	struct mutex update_lock;
74 	unsigned long last_battery;	/* In jiffies */
75 	char temp_valid;		/* !=0 if following fields are valid */
76 	char fan_valid;
77 	char in_valid;
78 	unsigned long temp_last_updated;	/* In jiffies */
79 	unsigned long fan_last_updated;
80 	unsigned long in_last_updated;
81 	u16 temp[SCH5627_NO_TEMPS];
82 	u16 fan[SCH5627_NO_FANS];
83 	u16 in[SCH5627_NO_IN];
84 };
85 
86 static int sch5627_update_temp(struct sch5627_data *data)
87 {
88 	int ret = 0;
89 	int i, val;
90 
91 	mutex_lock(&data->update_lock);
92 
93 	/* Cache the values for 1 second */
94 	if (time_after(jiffies, data->temp_last_updated + HZ) || !data->temp_valid) {
95 		for (i = 0; i < SCH5627_NO_TEMPS; i++) {
96 			val = sch56xx_read_virtual_reg12(data->addr, SCH5627_REG_TEMP_MSB[i],
97 							 SCH5627_REG_TEMP_LSN[i],
98 							 SCH5627_REG_TEMP_HIGH_NIBBLE[i]);
99 			if (unlikely(val < 0)) {
100 				ret = val;
101 				goto abort;
102 			}
103 			data->temp[i] = val;
104 		}
105 		data->temp_last_updated = jiffies;
106 		data->temp_valid = 1;
107 	}
108 abort:
109 	mutex_unlock(&data->update_lock);
110 	return ret;
111 }
112 
113 static int sch5627_update_fan(struct sch5627_data *data)
114 {
115 	int ret = 0;
116 	int i, val;
117 
118 	mutex_lock(&data->update_lock);
119 
120 	/* Cache the values for 1 second */
121 	if (time_after(jiffies, data->fan_last_updated + HZ) || !data->fan_valid) {
122 		for (i = 0; i < SCH5627_NO_FANS; i++) {
123 			val = sch56xx_read_virtual_reg16(data->addr, SCH5627_REG_FAN[i]);
124 			if (unlikely(val < 0)) {
125 				ret = val;
126 				goto abort;
127 			}
128 			data->fan[i] = val;
129 		}
130 		data->fan_last_updated = jiffies;
131 		data->fan_valid = 1;
132 	}
133 abort:
134 	mutex_unlock(&data->update_lock);
135 	return ret;
136 }
137 
138 static int sch5627_update_in(struct sch5627_data *data)
139 {
140 	int ret = 0;
141 	int i, val;
142 
143 	mutex_lock(&data->update_lock);
144 
145 	/* Trigger a Vbat voltage measurement every 5 minutes */
146 	if (time_after(jiffies, data->last_battery + 300 * HZ)) {
147 		sch56xx_write_virtual_reg(data->addr, SCH5627_REG_CTRL, data->control | 0x10);
148 		data->last_battery = jiffies;
149 	}
150 
151 	/* Cache the values for 1 second */
152 	if (time_after(jiffies, data->in_last_updated + HZ) || !data->in_valid) {
153 		for (i = 0; i < SCH5627_NO_IN; i++) {
154 			val = sch56xx_read_virtual_reg12(data->addr, SCH5627_REG_IN_MSB[i],
155 							 SCH5627_REG_IN_LSN[i],
156 							 SCH5627_REG_IN_HIGH_NIBBLE[i]);
157 			if (unlikely(val < 0)) {
158 				ret = val;
159 				goto abort;
160 			}
161 			data->in[i] = val;
162 		}
163 		data->in_last_updated = jiffies;
164 		data->in_valid = 1;
165 	}
166 abort:
167 	mutex_unlock(&data->update_lock);
168 	return ret;
169 }
170 
171 static int sch5627_read_limits(struct sch5627_data *data)
172 {
173 	int i, val;
174 
175 	for (i = 0; i < SCH5627_NO_TEMPS; i++) {
176 		/*
177 		 * Note what SMSC calls ABS, is what lm_sensors calls max
178 		 * (aka high), and HIGH is what lm_sensors calls crit.
179 		 */
180 		val = sch56xx_read_virtual_reg(data->addr,
181 					       SCH5627_REG_TEMP_ABS[i]);
182 		if (val < 0)
183 			return val;
184 		data->temp_max[i] = val;
185 
186 		val = sch56xx_read_virtual_reg(data->addr,
187 					       SCH5627_REG_TEMP_HIGH[i]);
188 		if (val < 0)
189 			return val;
190 		data->temp_crit[i] = val;
191 	}
192 	for (i = 0; i < SCH5627_NO_FANS; i++) {
193 		val = sch56xx_read_virtual_reg16(data->addr,
194 						 SCH5627_REG_FAN_MIN[i]);
195 		if (val < 0)
196 			return val;
197 		data->fan_min[i] = val;
198 	}
199 
200 	return 0;
201 }
202 
203 static int reg_to_temp(u16 reg)
204 {
205 	return (reg * 625) / 10 - 64000;
206 }
207 
208 static int reg_to_temp_limit(u8 reg)
209 {
210 	return (reg - 64) * 1000;
211 }
212 
213 static int reg_to_rpm(u16 reg)
214 {
215 	if (reg == 0)
216 		return -EIO;
217 	if (reg == 0xffff)
218 		return 0;
219 
220 	return 5400540 / reg;
221 }
222 
223 static umode_t sch5627_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr,
224 				  int channel)
225 {
226 	return 0444;
227 }
228 
229 static int sch5627_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
230 			long *val)
231 {
232 	struct sch5627_data *data = dev_get_drvdata(dev);
233 	int ret;
234 
235 	switch (type) {
236 	case hwmon_temp:
237 		ret = sch5627_update_temp(data);
238 		if (ret < 0)
239 			return ret;
240 		switch (attr) {
241 		case hwmon_temp_input:
242 			*val = reg_to_temp(data->temp[channel]);
243 			return 0;
244 		case hwmon_temp_max:
245 			*val = reg_to_temp_limit(data->temp_max[channel]);
246 			return 0;
247 		case hwmon_temp_crit:
248 			*val = reg_to_temp_limit(data->temp_crit[channel]);
249 			return 0;
250 		case hwmon_temp_fault:
251 			*val = (data->temp[channel] == 0);
252 			return 0;
253 		default:
254 			break;
255 		}
256 		break;
257 	case hwmon_fan:
258 		ret = sch5627_update_fan(data);
259 		if (ret < 0)
260 			return ret;
261 		switch (attr) {
262 		case hwmon_fan_input:
263 			ret = reg_to_rpm(data->fan[channel]);
264 			if (ret < 0)
265 				return ret;
266 			*val = ret;
267 			return 0;
268 		case hwmon_fan_min:
269 			ret = reg_to_rpm(data->fan_min[channel]);
270 			if (ret < 0)
271 				return ret;
272 			*val = ret;
273 			return 0;
274 		case hwmon_fan_fault:
275 			*val = (data->fan[channel] == 0xffff);
276 			return 0;
277 		default:
278 			break;
279 		}
280 		break;
281 	case hwmon_in:
282 		ret = sch5627_update_in(data);
283 		if (ret < 0)
284 			return ret;
285 		switch (attr) {
286 		case hwmon_in_input:
287 			*val = DIV_ROUND_CLOSEST(data->in[channel] * SCH5627_REG_IN_FACTOR[channel],
288 						 10000);
289 			return 0;
290 		default:
291 			break;
292 		}
293 		break;
294 	default:
295 		break;
296 	}
297 
298 	return -EOPNOTSUPP;
299 }
300 
301 static int sch5627_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr,
302 			       int channel, const char **str)
303 {
304 	switch (type) {
305 	case hwmon_in:
306 		switch (attr) {
307 		case hwmon_in_label:
308 			*str = SCH5627_IN_LABELS[channel];
309 			return 0;
310 		default:
311 			break;
312 		}
313 		break;
314 	default:
315 		break;
316 	}
317 
318 	return -EOPNOTSUPP;
319 }
320 
321 static const struct hwmon_ops sch5627_ops = {
322 	.is_visible = sch5627_is_visible,
323 	.read = sch5627_read,
324 	.read_string = sch5627_read_string,
325 };
326 
327 static const struct hwmon_channel_info *sch5627_info[] = {
328 	HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
329 	HWMON_CHANNEL_INFO(temp,
330 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_FAULT,
331 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_FAULT,
332 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_FAULT,
333 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_FAULT,
334 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_FAULT,
335 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_FAULT,
336 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_FAULT,
337 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_FAULT
338 			   ),
339 	HWMON_CHANNEL_INFO(fan,
340 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_FAULT,
341 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_FAULT,
342 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_FAULT,
343 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_FAULT
344 			   ),
345 	HWMON_CHANNEL_INFO(in,
346 			   HWMON_I_INPUT | HWMON_I_LABEL,
347 			   HWMON_I_INPUT | HWMON_I_LABEL,
348 			   HWMON_I_INPUT | HWMON_I_LABEL,
349 			   HWMON_I_INPUT | HWMON_I_LABEL,
350 			   HWMON_I_INPUT
351 			   ),
352 	NULL
353 };
354 
355 static const struct hwmon_chip_info sch5627_chip_info = {
356 	.ops = &sch5627_ops,
357 	.info = sch5627_info,
358 };
359 
360 static int sch5627_remove(struct platform_device *pdev)
361 {
362 	struct sch5627_data *data = platform_get_drvdata(pdev);
363 
364 	if (data->watchdog)
365 		sch56xx_watchdog_unregister(data->watchdog);
366 
367 	return 0;
368 }
369 
370 static int sch5627_probe(struct platform_device *pdev)
371 {
372 	struct sch5627_data *data;
373 	struct device *hwmon_dev;
374 	int err, build_code, build_id, hwmon_rev, val;
375 
376 	data = devm_kzalloc(&pdev->dev, sizeof(struct sch5627_data),
377 			    GFP_KERNEL);
378 	if (!data)
379 		return -ENOMEM;
380 
381 	data->addr = platform_get_resource(pdev, IORESOURCE_IO, 0)->start;
382 	mutex_init(&data->update_lock);
383 	platform_set_drvdata(pdev, data);
384 
385 	val = sch56xx_read_virtual_reg(data->addr, SCH5627_REG_HWMON_ID);
386 	if (val < 0)
387 		return val;
388 
389 	if (val != SCH5627_HWMON_ID) {
390 		pr_err("invalid %s id: 0x%02X (expected 0x%02X)\n", "hwmon",
391 		       val, SCH5627_HWMON_ID);
392 		return -ENODEV;
393 	}
394 
395 	val = sch56xx_read_virtual_reg(data->addr, SCH5627_REG_COMPANY_ID);
396 	if (val < 0)
397 		return val;
398 
399 	if (val != SCH5627_COMPANY_ID) {
400 		pr_err("invalid %s id: 0x%02X (expected 0x%02X)\n", "company",
401 		       val, SCH5627_COMPANY_ID);
402 		return -ENODEV;
403 	}
404 
405 	val = sch56xx_read_virtual_reg(data->addr, SCH5627_REG_PRIMARY_ID);
406 	if (val < 0)
407 		return val;
408 
409 	if (val != SCH5627_PRIMARY_ID) {
410 		pr_err("invalid %s id: 0x%02X (expected 0x%02X)\n", "primary",
411 		       val, SCH5627_PRIMARY_ID);
412 		return -ENODEV;
413 	}
414 
415 	build_code = sch56xx_read_virtual_reg(data->addr,
416 					      SCH5627_REG_BUILD_CODE);
417 	if (build_code < 0)
418 		return build_code;
419 
420 	build_id = sch56xx_read_virtual_reg16(data->addr,
421 					      SCH5627_REG_BUILD_ID);
422 	if (build_id < 0)
423 		return build_id;
424 
425 	hwmon_rev = sch56xx_read_virtual_reg(data->addr,
426 					     SCH5627_REG_HWMON_REV);
427 	if (hwmon_rev < 0)
428 		return hwmon_rev;
429 
430 	val = sch56xx_read_virtual_reg(data->addr, SCH5627_REG_CTRL);
431 	if (val < 0)
432 		return val;
433 
434 	data->control = val;
435 	if (!(data->control & 0x01)) {
436 		pr_err("hardware monitoring not enabled\n");
437 		return -ENODEV;
438 	}
439 	/* Trigger a Vbat voltage measurement, so that we get a valid reading
440 	   the first time we read Vbat */
441 	sch56xx_write_virtual_reg(data->addr, SCH5627_REG_CTRL,
442 				  data->control | 0x10);
443 	data->last_battery = jiffies;
444 
445 	/*
446 	 * Read limits, we do this only once as reading a register on
447 	 * the sch5627 is quite expensive (and they don't change).
448 	 */
449 	err = sch5627_read_limits(data);
450 	if (err)
451 		return err;
452 
453 	pr_info("found %s chip at %#hx\n", DEVNAME, data->addr);
454 	pr_info("firmware build: code 0x%02X, id 0x%04X, hwmon: rev 0x%02X\n",
455 		build_code, build_id, hwmon_rev);
456 
457 	hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev, DEVNAME, data,
458 							 &sch5627_chip_info, NULL);
459 	if (IS_ERR(hwmon_dev))
460 		return PTR_ERR(hwmon_dev);
461 
462 	/* Note failing to register the watchdog is not a fatal error */
463 	data->watchdog = sch56xx_watchdog_register(&pdev->dev, data->addr,
464 			(build_code << 24) | (build_id << 8) | hwmon_rev,
465 			&data->update_lock, 1);
466 
467 	return 0;
468 }
469 
470 static struct platform_driver sch5627_driver = {
471 	.driver = {
472 		.name	= DRVNAME,
473 	},
474 	.probe		= sch5627_probe,
475 	.remove		= sch5627_remove,
476 };
477 
478 module_platform_driver(sch5627_driver);
479 
480 MODULE_DESCRIPTION("SMSC SCH5627 Hardware Monitoring Driver");
481 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
482 MODULE_LICENSE("GPL");
483