xref: /openbmc/linux/drivers/hwmon/sch5627.c (revision 2326f3cd)
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 	u8 control;
68 	u8 temp_max[SCH5627_NO_TEMPS];
69 	u8 temp_crit[SCH5627_NO_TEMPS];
70 	u16 fan_min[SCH5627_NO_FANS];
71 
72 	struct mutex update_lock;
73 	unsigned long last_battery;	/* In jiffies */
74 	char temp_valid;		/* !=0 if following fields are valid */
75 	char fan_valid;
76 	char in_valid;
77 	unsigned long temp_last_updated;	/* In jiffies */
78 	unsigned long fan_last_updated;
79 	unsigned long in_last_updated;
80 	u16 temp[SCH5627_NO_TEMPS];
81 	u16 fan[SCH5627_NO_FANS];
82 	u16 in[SCH5627_NO_IN];
83 };
84 
85 static int sch5627_update_temp(struct sch5627_data *data)
86 {
87 	int ret = 0;
88 	int i, val;
89 
90 	mutex_lock(&data->update_lock);
91 
92 	/* Cache the values for 1 second */
93 	if (time_after(jiffies, data->temp_last_updated + HZ) || !data->temp_valid) {
94 		for (i = 0; i < SCH5627_NO_TEMPS; i++) {
95 			val = sch56xx_read_virtual_reg12(data->addr, SCH5627_REG_TEMP_MSB[i],
96 							 SCH5627_REG_TEMP_LSN[i],
97 							 SCH5627_REG_TEMP_HIGH_NIBBLE[i]);
98 			if (unlikely(val < 0)) {
99 				ret = val;
100 				goto abort;
101 			}
102 			data->temp[i] = val;
103 		}
104 		data->temp_last_updated = jiffies;
105 		data->temp_valid = 1;
106 	}
107 abort:
108 	mutex_unlock(&data->update_lock);
109 	return ret;
110 }
111 
112 static int sch5627_update_fan(struct sch5627_data *data)
113 {
114 	int ret = 0;
115 	int i, val;
116 
117 	mutex_lock(&data->update_lock);
118 
119 	/* Cache the values for 1 second */
120 	if (time_after(jiffies, data->fan_last_updated + HZ) || !data->fan_valid) {
121 		for (i = 0; i < SCH5627_NO_FANS; i++) {
122 			val = sch56xx_read_virtual_reg16(data->addr, SCH5627_REG_FAN[i]);
123 			if (unlikely(val < 0)) {
124 				ret = val;
125 				goto abort;
126 			}
127 			data->fan[i] = val;
128 		}
129 		data->fan_last_updated = jiffies;
130 		data->fan_valid = 1;
131 	}
132 abort:
133 	mutex_unlock(&data->update_lock);
134 	return ret;
135 }
136 
137 static int sch5627_update_in(struct sch5627_data *data)
138 {
139 	int ret = 0;
140 	int i, val;
141 
142 	mutex_lock(&data->update_lock);
143 
144 	/* Trigger a Vbat voltage measurement every 5 minutes */
145 	if (time_after(jiffies, data->last_battery + 300 * HZ)) {
146 		sch56xx_write_virtual_reg(data->addr, SCH5627_REG_CTRL, data->control | 0x10);
147 		data->last_battery = jiffies;
148 	}
149 
150 	/* Cache the values for 1 second */
151 	if (time_after(jiffies, data->in_last_updated + HZ) || !data->in_valid) {
152 		for (i = 0; i < SCH5627_NO_IN; i++) {
153 			val = sch56xx_read_virtual_reg12(data->addr, SCH5627_REG_IN_MSB[i],
154 							 SCH5627_REG_IN_LSN[i],
155 							 SCH5627_REG_IN_HIGH_NIBBLE[i]);
156 			if (unlikely(val < 0)) {
157 				ret = val;
158 				goto abort;
159 			}
160 			data->in[i] = val;
161 		}
162 		data->in_last_updated = jiffies;
163 		data->in_valid = 1;
164 	}
165 abort:
166 	mutex_unlock(&data->update_lock);
167 	return ret;
168 }
169 
170 static int sch5627_read_limits(struct sch5627_data *data)
171 {
172 	int i, val;
173 
174 	for (i = 0; i < SCH5627_NO_TEMPS; i++) {
175 		/*
176 		 * Note what SMSC calls ABS, is what lm_sensors calls max
177 		 * (aka high), and HIGH is what lm_sensors calls crit.
178 		 */
179 		val = sch56xx_read_virtual_reg(data->addr,
180 					       SCH5627_REG_TEMP_ABS[i]);
181 		if (val < 0)
182 			return val;
183 		data->temp_max[i] = val;
184 
185 		val = sch56xx_read_virtual_reg(data->addr,
186 					       SCH5627_REG_TEMP_HIGH[i]);
187 		if (val < 0)
188 			return val;
189 		data->temp_crit[i] = val;
190 	}
191 	for (i = 0; i < SCH5627_NO_FANS; i++) {
192 		val = sch56xx_read_virtual_reg16(data->addr,
193 						 SCH5627_REG_FAN_MIN[i]);
194 		if (val < 0)
195 			return val;
196 		data->fan_min[i] = val;
197 	}
198 
199 	return 0;
200 }
201 
202 static int reg_to_temp(u16 reg)
203 {
204 	return (reg * 625) / 10 - 64000;
205 }
206 
207 static int reg_to_temp_limit(u8 reg)
208 {
209 	return (reg - 64) * 1000;
210 }
211 
212 static int reg_to_rpm(u16 reg)
213 {
214 	if (reg == 0)
215 		return -EIO;
216 	if (reg == 0xffff)
217 		return 0;
218 
219 	return 5400540 / reg;
220 }
221 
222 static umode_t sch5627_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr,
223 				  int channel)
224 {
225 	return 0444;
226 }
227 
228 static int sch5627_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
229 			long *val)
230 {
231 	struct sch5627_data *data = dev_get_drvdata(dev);
232 	int ret;
233 
234 	switch (type) {
235 	case hwmon_temp:
236 		ret = sch5627_update_temp(data);
237 		if (ret < 0)
238 			return ret;
239 		switch (attr) {
240 		case hwmon_temp_input:
241 			*val = reg_to_temp(data->temp[channel]);
242 			return 0;
243 		case hwmon_temp_max:
244 			*val = reg_to_temp_limit(data->temp_max[channel]);
245 			return 0;
246 		case hwmon_temp_crit:
247 			*val = reg_to_temp_limit(data->temp_crit[channel]);
248 			return 0;
249 		case hwmon_temp_fault:
250 			*val = (data->temp[channel] == 0);
251 			return 0;
252 		default:
253 			break;
254 		}
255 		break;
256 	case hwmon_fan:
257 		ret = sch5627_update_fan(data);
258 		if (ret < 0)
259 			return ret;
260 		switch (attr) {
261 		case hwmon_fan_input:
262 			ret = reg_to_rpm(data->fan[channel]);
263 			if (ret < 0)
264 				return ret;
265 			*val = ret;
266 			return 0;
267 		case hwmon_fan_min:
268 			ret = reg_to_rpm(data->fan_min[channel]);
269 			if (ret < 0)
270 				return ret;
271 			*val = ret;
272 			return 0;
273 		case hwmon_fan_fault:
274 			*val = (data->fan[channel] == 0xffff);
275 			return 0;
276 		default:
277 			break;
278 		}
279 		break;
280 	case hwmon_in:
281 		ret = sch5627_update_in(data);
282 		if (ret < 0)
283 			return ret;
284 		switch (attr) {
285 		case hwmon_in_input:
286 			*val = DIV_ROUND_CLOSEST(data->in[channel] * SCH5627_REG_IN_FACTOR[channel],
287 						 10000);
288 			return 0;
289 		default:
290 			break;
291 		}
292 		break;
293 	default:
294 		break;
295 	}
296 
297 	return -EOPNOTSUPP;
298 }
299 
300 static int sch5627_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr,
301 			       int channel, const char **str)
302 {
303 	switch (type) {
304 	case hwmon_in:
305 		switch (attr) {
306 		case hwmon_in_label:
307 			*str = SCH5627_IN_LABELS[channel];
308 			return 0;
309 		default:
310 			break;
311 		}
312 		break;
313 	default:
314 		break;
315 	}
316 
317 	return -EOPNOTSUPP;
318 }
319 
320 static const struct hwmon_ops sch5627_ops = {
321 	.is_visible = sch5627_is_visible,
322 	.read = sch5627_read,
323 	.read_string = sch5627_read_string,
324 };
325 
326 static const struct hwmon_channel_info *sch5627_info[] = {
327 	HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
328 	HWMON_CHANNEL_INFO(temp,
329 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_FAULT,
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 			   ),
338 	HWMON_CHANNEL_INFO(fan,
339 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_FAULT,
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 			   ),
344 	HWMON_CHANNEL_INFO(in,
345 			   HWMON_I_INPUT | HWMON_I_LABEL,
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
350 			   ),
351 	NULL
352 };
353 
354 static const struct hwmon_chip_info sch5627_chip_info = {
355 	.ops = &sch5627_ops,
356 	.info = sch5627_info,
357 };
358 
359 static int sch5627_probe(struct platform_device *pdev)
360 {
361 	struct sch5627_data *data;
362 	struct device *hwmon_dev;
363 	int err, build_code, build_id, hwmon_rev, val;
364 
365 	data = devm_kzalloc(&pdev->dev, sizeof(struct sch5627_data),
366 			    GFP_KERNEL);
367 	if (!data)
368 		return -ENOMEM;
369 
370 	data->addr = platform_get_resource(pdev, IORESOURCE_IO, 0)->start;
371 	mutex_init(&data->update_lock);
372 	platform_set_drvdata(pdev, data);
373 
374 	val = sch56xx_read_virtual_reg(data->addr, SCH5627_REG_HWMON_ID);
375 	if (val < 0)
376 		return val;
377 
378 	if (val != SCH5627_HWMON_ID) {
379 		pr_err("invalid %s id: 0x%02X (expected 0x%02X)\n", "hwmon",
380 		       val, SCH5627_HWMON_ID);
381 		return -ENODEV;
382 	}
383 
384 	val = sch56xx_read_virtual_reg(data->addr, SCH5627_REG_COMPANY_ID);
385 	if (val < 0)
386 		return val;
387 
388 	if (val != SCH5627_COMPANY_ID) {
389 		pr_err("invalid %s id: 0x%02X (expected 0x%02X)\n", "company",
390 		       val, SCH5627_COMPANY_ID);
391 		return -ENODEV;
392 	}
393 
394 	val = sch56xx_read_virtual_reg(data->addr, SCH5627_REG_PRIMARY_ID);
395 	if (val < 0)
396 		return val;
397 
398 	if (val != SCH5627_PRIMARY_ID) {
399 		pr_err("invalid %s id: 0x%02X (expected 0x%02X)\n", "primary",
400 		       val, SCH5627_PRIMARY_ID);
401 		return -ENODEV;
402 	}
403 
404 	build_code = sch56xx_read_virtual_reg(data->addr,
405 					      SCH5627_REG_BUILD_CODE);
406 	if (build_code < 0)
407 		return build_code;
408 
409 	build_id = sch56xx_read_virtual_reg16(data->addr,
410 					      SCH5627_REG_BUILD_ID);
411 	if (build_id < 0)
412 		return build_id;
413 
414 	hwmon_rev = sch56xx_read_virtual_reg(data->addr,
415 					     SCH5627_REG_HWMON_REV);
416 	if (hwmon_rev < 0)
417 		return hwmon_rev;
418 
419 	val = sch56xx_read_virtual_reg(data->addr, SCH5627_REG_CTRL);
420 	if (val < 0)
421 		return val;
422 
423 	data->control = val;
424 	if (!(data->control & 0x01)) {
425 		pr_err("hardware monitoring not enabled\n");
426 		return -ENODEV;
427 	}
428 	/* Trigger a Vbat voltage measurement, so that we get a valid reading
429 	   the first time we read Vbat */
430 	sch56xx_write_virtual_reg(data->addr, SCH5627_REG_CTRL,
431 				  data->control | 0x10);
432 	data->last_battery = jiffies;
433 
434 	/*
435 	 * Read limits, we do this only once as reading a register on
436 	 * the sch5627 is quite expensive (and they don't change).
437 	 */
438 	err = sch5627_read_limits(data);
439 	if (err)
440 		return err;
441 
442 	pr_info("found %s chip at %#hx\n", DEVNAME, data->addr);
443 	pr_info("firmware build: code 0x%02X, id 0x%04X, hwmon: rev 0x%02X\n",
444 		build_code, build_id, hwmon_rev);
445 
446 	hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev, DEVNAME, data,
447 							 &sch5627_chip_info, NULL);
448 	if (IS_ERR(hwmon_dev))
449 		return PTR_ERR(hwmon_dev);
450 
451 	/* Note failing to register the watchdog is not a fatal error */
452 	sch56xx_watchdog_register(&pdev->dev, data->addr,
453 				  (build_code << 24) | (build_id << 8) | hwmon_rev,
454 				  &data->update_lock, 1);
455 
456 	return 0;
457 }
458 
459 static struct platform_driver sch5627_driver = {
460 	.driver = {
461 		.name	= DRVNAME,
462 	},
463 	.probe		= sch5627_probe,
464 };
465 
466 module_platform_driver(sch5627_driver);
467 
468 MODULE_DESCRIPTION("SMSC SCH5627 Hardware Monitoring Driver");
469 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
470 MODULE_LICENSE("GPL");
471