xref: /linux/drivers/hwmon/pmbus/zl6100.c (revision 55d0969c451159cff86949b38c39171cab962069)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Hardware monitoring driver for ZL6100 and compatibles
4  *
5  * Copyright (c) 2011 Ericsson AB.
6  * Copyright (c) 2012 Guenter Roeck
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/err.h>
14 #include <linux/slab.h>
15 #include <linux/i2c.h>
16 #include <linux/ktime.h>
17 #include <linux/delay.h>
18 #include "pmbus.h"
19 
20 enum chips { zl2004, zl2005, zl2006, zl2008, zl2105, zl2106, zl6100, zl6105,
21 	     zl8802, zl9101, zl9117, zls1003, zls4009 };
22 
23 struct zl6100_data {
24 	int id;
25 	struct pmbus_driver_info info;
26 };
27 
28 #define to_zl6100_data(x)  container_of(x, struct zl6100_data, info)
29 
30 #define ZL6100_MFR_CONFIG		0xd0
31 #define ZL6100_DEVICE_ID		0xe4
32 
33 #define ZL6100_MFR_XTEMP_ENABLE		BIT(7)
34 
35 #define ZL8802_MFR_USER_GLOBAL_CONFIG	0xe9
36 #define ZL8802_MFR_TMON_ENABLE		BIT(12)
37 #define ZL8802_MFR_USER_CONFIG		0xd1
38 #define ZL8802_MFR_XTEMP_ENABLE_2	BIT(1)
39 #define ZL8802_MFR_DDC_CONFIG		0xd3
40 #define ZL8802_MFR_PHASES_MASK		0x0007
41 
42 #define MFR_VMON_OV_FAULT_LIMIT		0xf5
43 #define MFR_VMON_UV_FAULT_LIMIT		0xf6
44 #define MFR_READ_VMON			0xf7
45 
46 #define VMON_UV_WARNING			BIT(5)
47 #define VMON_OV_WARNING			BIT(4)
48 #define VMON_UV_FAULT			BIT(1)
49 #define VMON_OV_FAULT			BIT(0)
50 
51 #define ZL6100_WAIT_TIME		1000	/* uS	*/
52 
53 static ushort delay = ZL6100_WAIT_TIME;
54 module_param(delay, ushort, 0644);
55 MODULE_PARM_DESC(delay, "Delay between chip accesses in uS");
56 
57 /* Convert linear sensor value to milli-units */
58 static long zl6100_l2d(s16 l)
59 {
60 	s16 exponent;
61 	s32 mantissa;
62 	long val;
63 
64 	exponent = l >> 11;
65 	mantissa = ((s16)((l & 0x7ff) << 5)) >> 5;
66 
67 	val = mantissa;
68 
69 	/* scale result to milli-units */
70 	val = val * 1000L;
71 
72 	if (exponent >= 0)
73 		val <<= exponent;
74 	else
75 		val >>= -exponent;
76 
77 	return val;
78 }
79 
80 #define MAX_MANTISSA	(1023 * 1000)
81 #define MIN_MANTISSA	(511 * 1000)
82 
83 static u16 zl6100_d2l(long val)
84 {
85 	s16 exponent = 0, mantissa;
86 	bool negative = false;
87 
88 	/* simple case */
89 	if (val == 0)
90 		return 0;
91 
92 	if (val < 0) {
93 		negative = true;
94 		val = -val;
95 	}
96 
97 	/* Reduce large mantissa until it fits into 10 bit */
98 	while (val >= MAX_MANTISSA && exponent < 15) {
99 		exponent++;
100 		val >>= 1;
101 	}
102 	/* Increase small mantissa to improve precision */
103 	while (val < MIN_MANTISSA && exponent > -15) {
104 		exponent--;
105 		val <<= 1;
106 	}
107 
108 	/* Convert mantissa from milli-units to units */
109 	mantissa = DIV_ROUND_CLOSEST(val, 1000);
110 
111 	/* Ensure that resulting number is within range */
112 	if (mantissa > 0x3ff)
113 		mantissa = 0x3ff;
114 
115 	/* restore sign */
116 	if (negative)
117 		mantissa = -mantissa;
118 
119 	/* Convert to 5 bit exponent, 11 bit mantissa */
120 	return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800);
121 }
122 
123 static int zl6100_read_word_data(struct i2c_client *client, int page,
124 				 int phase, int reg)
125 {
126 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
127 	struct zl6100_data *data = to_zl6100_data(info);
128 	int ret, vreg;
129 
130 	if (page >= info->pages)
131 		return -ENXIO;
132 
133 	if (data->id == zl2005) {
134 		/*
135 		 * Limit register detection is not reliable on ZL2005.
136 		 * Make sure registers are not erroneously detected.
137 		 */
138 		switch (reg) {
139 		case PMBUS_VOUT_OV_WARN_LIMIT:
140 		case PMBUS_VOUT_UV_WARN_LIMIT:
141 		case PMBUS_IOUT_OC_WARN_LIMIT:
142 			return -ENXIO;
143 		}
144 	}
145 
146 	switch (reg) {
147 	case PMBUS_VIRT_READ_VMON:
148 		vreg = MFR_READ_VMON;
149 		break;
150 	case PMBUS_VIRT_VMON_OV_WARN_LIMIT:
151 	case PMBUS_VIRT_VMON_OV_FAULT_LIMIT:
152 		vreg = MFR_VMON_OV_FAULT_LIMIT;
153 		break;
154 	case PMBUS_VIRT_VMON_UV_WARN_LIMIT:
155 	case PMBUS_VIRT_VMON_UV_FAULT_LIMIT:
156 		vreg = MFR_VMON_UV_FAULT_LIMIT;
157 		break;
158 	default:
159 		if (reg >= PMBUS_VIRT_BASE)
160 			return -ENXIO;
161 		vreg = reg;
162 		break;
163 	}
164 
165 	ret = pmbus_read_word_data(client, page, phase, vreg);
166 	if (ret < 0)
167 		return ret;
168 
169 	switch (reg) {
170 	case PMBUS_VIRT_VMON_OV_WARN_LIMIT:
171 		ret = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(ret) * 9, 10));
172 		break;
173 	case PMBUS_VIRT_VMON_UV_WARN_LIMIT:
174 		ret = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(ret) * 11, 10));
175 		break;
176 	}
177 
178 	return ret;
179 }
180 
181 static int zl6100_read_byte_data(struct i2c_client *client, int page, int reg)
182 {
183 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
184 	int ret, status;
185 
186 	if (page >= info->pages)
187 		return -ENXIO;
188 
189 	switch (reg) {
190 	case PMBUS_VIRT_STATUS_VMON:
191 		ret = pmbus_read_byte_data(client, 0,
192 					   PMBUS_STATUS_MFR_SPECIFIC);
193 		if (ret < 0)
194 			break;
195 
196 		status = 0;
197 		if (ret & VMON_UV_WARNING)
198 			status |= PB_VOLTAGE_UV_WARNING;
199 		if (ret & VMON_OV_WARNING)
200 			status |= PB_VOLTAGE_OV_WARNING;
201 		if (ret & VMON_UV_FAULT)
202 			status |= PB_VOLTAGE_UV_FAULT;
203 		if (ret & VMON_OV_FAULT)
204 			status |= PB_VOLTAGE_OV_FAULT;
205 		ret = status;
206 		break;
207 	default:
208 		ret = pmbus_read_byte_data(client, page, reg);
209 		break;
210 	}
211 
212 	return ret;
213 }
214 
215 static int zl6100_write_word_data(struct i2c_client *client, int page, int reg,
216 				  u16 word)
217 {
218 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
219 	int vreg;
220 
221 	if (page >= info->pages)
222 		return -ENXIO;
223 
224 	switch (reg) {
225 	case PMBUS_VIRT_VMON_OV_WARN_LIMIT:
226 		word = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(word) * 10, 9));
227 		vreg = MFR_VMON_OV_FAULT_LIMIT;
228 		pmbus_clear_cache(client);
229 		break;
230 	case PMBUS_VIRT_VMON_OV_FAULT_LIMIT:
231 		vreg = MFR_VMON_OV_FAULT_LIMIT;
232 		pmbus_clear_cache(client);
233 		break;
234 	case PMBUS_VIRT_VMON_UV_WARN_LIMIT:
235 		word = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(word) * 10, 11));
236 		vreg = MFR_VMON_UV_FAULT_LIMIT;
237 		pmbus_clear_cache(client);
238 		break;
239 	case PMBUS_VIRT_VMON_UV_FAULT_LIMIT:
240 		vreg = MFR_VMON_UV_FAULT_LIMIT;
241 		pmbus_clear_cache(client);
242 		break;
243 	default:
244 		if (reg >= PMBUS_VIRT_BASE)
245 			return -ENXIO;
246 		vreg = reg;
247 	}
248 
249 	return pmbus_write_word_data(client, page, vreg, word);
250 }
251 
252 static const struct i2c_device_id zl6100_id[] = {
253 	{"bmr450", zl2005},
254 	{"bmr451", zl2005},
255 	{"bmr462", zl2008},
256 	{"bmr463", zl2008},
257 	{"bmr464", zl2008},
258 	{"bmr465", zls4009},
259 	{"bmr466", zls1003},
260 	{"bmr467", zls4009},
261 	{"bmr469", zl8802},
262 	{"zl2004", zl2004},
263 	{"zl2005", zl2005},
264 	{"zl2006", zl2006},
265 	{"zl2008", zl2008},
266 	{"zl2105", zl2105},
267 	{"zl2106", zl2106},
268 	{"zl6100", zl6100},
269 	{"zl6105", zl6105},
270 	{"zl8802", zl8802},
271 	{"zl9101", zl9101},
272 	{"zl9117", zl9117},
273 	{"zls1003", zls1003},
274 	{"zls4009", zls4009},
275 	{ }
276 };
277 MODULE_DEVICE_TABLE(i2c, zl6100_id);
278 
279 static int zl6100_probe(struct i2c_client *client)
280 {
281 	int ret, i;
282 	struct zl6100_data *data;
283 	struct pmbus_driver_info *info;
284 	u8 device_id[I2C_SMBUS_BLOCK_MAX + 1];
285 	const struct i2c_device_id *mid;
286 
287 	if (!i2c_check_functionality(client->adapter,
288 				     I2C_FUNC_SMBUS_READ_WORD_DATA
289 				     | I2C_FUNC_SMBUS_READ_BLOCK_DATA))
290 		return -ENODEV;
291 
292 	ret = i2c_smbus_read_block_data(client, ZL6100_DEVICE_ID,
293 					device_id);
294 	if (ret < 0) {
295 		dev_err(&client->dev, "Failed to read device ID\n");
296 		return ret;
297 	}
298 	device_id[ret] = '\0';
299 	dev_info(&client->dev, "Device ID %s\n", device_id);
300 
301 	mid = NULL;
302 	for (mid = zl6100_id; mid->name[0]; mid++) {
303 		if (!strncasecmp(mid->name, device_id, strlen(mid->name)))
304 			break;
305 	}
306 	if (!mid->name[0]) {
307 		dev_err(&client->dev, "Unsupported device\n");
308 		return -ENODEV;
309 	}
310 	if (strcmp(client->name, mid->name) != 0)
311 		dev_notice(&client->dev,
312 			   "Device mismatch: Configured %s, detected %s\n",
313 			   client->name, mid->name);
314 
315 	data = devm_kzalloc(&client->dev, sizeof(struct zl6100_data),
316 			    GFP_KERNEL);
317 	if (!data)
318 		return -ENOMEM;
319 
320 	data->id = mid->driver_data;
321 
322 	/*
323 	 * According to information from the chip vendor, all currently
324 	 * supported chips are known to require a wait time between I2C
325 	 * accesses.
326 	 */
327 	udelay(delay);
328 
329 	info = &data->info;
330 
331 	info->pages = 1;
332 	info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
333 	  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
334 	  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
335 	  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
336 
337 	/*
338 	 * ZL2004, ZL8802, ZL9101M, ZL9117M and ZLS4009 support monitoring
339 	 * an extra voltage (VMON for ZL2004, ZL8802 and ZLS4009,
340 	 * VDRV for ZL9101M and ZL9117M). Report it as vmon.
341 	 */
342 	if (data->id == zl2004 || data->id == zl8802 || data->id == zl9101 ||
343 	    data->id == zl9117 || data->id == zls4009)
344 		info->func[0] |= PMBUS_HAVE_VMON | PMBUS_HAVE_STATUS_VMON;
345 
346 	/*
347 	 * ZL8802 has two outputs that can be used either independently or in
348 	 * a current sharing configuration. The driver uses the DDC_CONFIG
349 	 * register to check if the module is running with independent or
350 	 * shared outputs. If the module is in shared output mode, only one
351 	 * output voltage will be reported.
352 	 */
353 	if (data->id == zl8802) {
354 		info->pages = 2;
355 		info->func[0] |= PMBUS_HAVE_IIN;
356 
357 		ret = i2c_smbus_read_word_data(client, ZL8802_MFR_DDC_CONFIG);
358 		if (ret < 0)
359 			return ret;
360 
361 		udelay(delay);
362 
363 		if (ret & ZL8802_MFR_PHASES_MASK)
364 			info->func[1] |= PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT;
365 		else
366 			info->func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
367 				| PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT;
368 
369 		for (i = 0; i < 2; i++) {
370 			ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i);
371 			if (ret < 0)
372 				return ret;
373 
374 			udelay(delay);
375 
376 			ret = i2c_smbus_read_word_data(client, ZL8802_MFR_USER_CONFIG);
377 			if (ret < 0)
378 				return ret;
379 
380 			if (ret & ZL8802_MFR_XTEMP_ENABLE_2)
381 				info->func[i] |= PMBUS_HAVE_TEMP2;
382 
383 			udelay(delay);
384 		}
385 		ret = i2c_smbus_read_word_data(client, ZL8802_MFR_USER_GLOBAL_CONFIG);
386 		if (ret < 0)
387 			return ret;
388 
389 		if (ret & ZL8802_MFR_TMON_ENABLE)
390 			info->func[0] |= PMBUS_HAVE_TEMP3;
391 	} else {
392 		ret = i2c_smbus_read_word_data(client, ZL6100_MFR_CONFIG);
393 		if (ret < 0)
394 			return ret;
395 
396 		if (ret & ZL6100_MFR_XTEMP_ENABLE)
397 			info->func[0] |= PMBUS_HAVE_TEMP2;
398 	}
399 
400 	udelay(delay);
401 
402 	info->access_delay = delay;
403 	info->read_word_data = zl6100_read_word_data;
404 	info->read_byte_data = zl6100_read_byte_data;
405 	info->write_word_data = zl6100_write_word_data;
406 
407 	return pmbus_do_probe(client, info);
408 }
409 
410 static struct i2c_driver zl6100_driver = {
411 	.driver = {
412 		   .name = "zl6100",
413 		   },
414 	.probe = zl6100_probe,
415 	.id_table = zl6100_id,
416 };
417 
418 module_i2c_driver(zl6100_driver);
419 
420 MODULE_AUTHOR("Guenter Roeck");
421 MODULE_DESCRIPTION("PMBus driver for ZL6100 and compatibles");
422 MODULE_LICENSE("GPL");
423 MODULE_IMPORT_NS(PMBUS);
424