zl6100.c

  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
 20enum chips { zl2004, zl2005, zl2006, zl2008, zl2105, zl2106, zl6100, zl6105,
 21	     zl8802, zl9101, zl9117, zls1003, zls4009 };
 22
 23struct 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
 53static ushort delay = ZL6100_WAIT_TIME;
 54module_param(delay, ushort, 0644);
 55MODULE_PARM_DESC(delay, "Delay between chip accesses in uS");
 56
 57/* Convert linear sensor value to milli-units */
 58static 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
 83static 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
123static 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
181static 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
215static 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
252static 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};
277MODULE_DEVICE_TABLE(i2c, zl6100_id);
278
279static 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
410static struct i2c_driver zl6100_driver = {
411	.driver = {
412		   .name = "zl6100",
413		   },
414	.probe = zl6100_probe,
415	.id_table = zl6100_id,
416};
417
418module_i2c_driver(zl6100_driver);
419
420MODULE_AUTHOR("Guenter Roeck");
421MODULE_DESCRIPTION("PMBus driver for ZL6100 and compatibles");
422MODULE_LICENSE("GPL");
423MODULE_IMPORT_NS("PMBUS");