1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Hardware monitoring driver for ZL6100 and compatibles
5 * Copyright (c) 2011 Ericsson AB.
6 * Copyright (c) 2012 Guenter Roeck
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>
20 enum chips { zl2004, zl2005, zl2006, zl2008, zl2105, zl2106, zl6100, zl6105,
25 ktime_t access; /* chip access time */
26 int delay; /* Delay between chip accesses in uS */
27 struct pmbus_driver_info info;
30 #define to_zl6100_data(x) container_of(x, struct zl6100_data, info)
32 #define ZL6100_MFR_CONFIG 0xd0
33 #define ZL6100_DEVICE_ID 0xe4
35 #define ZL6100_MFR_XTEMP_ENABLE BIT(7)
37 #define MFR_VMON_OV_FAULT_LIMIT 0xf5
38 #define MFR_VMON_UV_FAULT_LIMIT 0xf6
39 #define MFR_READ_VMON 0xf7
41 #define VMON_UV_WARNING BIT(5)
42 #define VMON_OV_WARNING BIT(4)
43 #define VMON_UV_FAULT BIT(1)
44 #define VMON_OV_FAULT BIT(0)
46 #define ZL6100_WAIT_TIME 1000 /* uS */
48 static ushort delay = ZL6100_WAIT_TIME;
49 module_param(delay, ushort, 0644);
50 MODULE_PARM_DESC(delay, "Delay between chip accesses in uS");
52 /* Convert linear sensor value to milli-units */
53 static long zl6100_l2d(s16 l)
60 mantissa = ((s16)((l & 0x7ff) << 5)) >> 5;
64 /* scale result to milli-units */
75 #define MAX_MANTISSA (1023 * 1000)
76 #define MIN_MANTISSA (511 * 1000)
78 static u16 zl6100_d2l(long val)
80 s16 exponent = 0, mantissa;
81 bool negative = false;
92 /* Reduce large mantissa until it fits into 10 bit */
93 while (val >= MAX_MANTISSA && exponent < 15) {
97 /* Increase small mantissa to improve precision */
98 while (val < MIN_MANTISSA && exponent > -15) {
103 /* Convert mantissa from milli-units to units */
104 mantissa = DIV_ROUND_CLOSEST(val, 1000);
106 /* Ensure that resulting number is within range */
107 if (mantissa > 0x3ff)
112 mantissa = -mantissa;
114 /* Convert to 5 bit exponent, 11 bit mantissa */
115 return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800);
118 /* Some chips need a delay between accesses */
119 static inline void zl6100_wait(const struct zl6100_data *data)
122 s64 delta = ktime_us_delta(ktime_get(), data->access);
123 if (delta < data->delay)
124 udelay(data->delay - delta);
128 static int zl6100_read_word_data(struct i2c_client *client, int page,
131 const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
132 struct zl6100_data *data = to_zl6100_data(info);
138 if (data->id == zl2005) {
140 * Limit register detection is not reliable on ZL2005.
141 * Make sure registers are not erroneously detected.
144 case PMBUS_VOUT_OV_WARN_LIMIT:
145 case PMBUS_VOUT_UV_WARN_LIMIT:
146 case PMBUS_IOUT_OC_WARN_LIMIT:
152 case PMBUS_VIRT_READ_VMON:
153 vreg = MFR_READ_VMON;
155 case PMBUS_VIRT_VMON_OV_WARN_LIMIT:
156 case PMBUS_VIRT_VMON_OV_FAULT_LIMIT:
157 vreg = MFR_VMON_OV_FAULT_LIMIT;
159 case PMBUS_VIRT_VMON_UV_WARN_LIMIT:
160 case PMBUS_VIRT_VMON_UV_FAULT_LIMIT:
161 vreg = MFR_VMON_UV_FAULT_LIMIT;
164 if (reg >= PMBUS_VIRT_BASE)
171 ret = pmbus_read_word_data(client, page, phase, vreg);
172 data->access = ktime_get();
177 case PMBUS_VIRT_VMON_OV_WARN_LIMIT:
178 ret = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(ret) * 9, 10));
180 case PMBUS_VIRT_VMON_UV_WARN_LIMIT:
181 ret = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(ret) * 11, 10));
188 static int zl6100_read_byte_data(struct i2c_client *client, int page, int reg)
190 const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
191 struct zl6100_data *data = to_zl6100_data(info);
200 case PMBUS_VIRT_STATUS_VMON:
201 ret = pmbus_read_byte_data(client, 0,
202 PMBUS_STATUS_MFR_SPECIFIC);
207 if (ret & VMON_UV_WARNING)
208 status |= PB_VOLTAGE_UV_WARNING;
209 if (ret & VMON_OV_WARNING)
210 status |= PB_VOLTAGE_OV_WARNING;
211 if (ret & VMON_UV_FAULT)
212 status |= PB_VOLTAGE_UV_FAULT;
213 if (ret & VMON_OV_FAULT)
214 status |= PB_VOLTAGE_OV_FAULT;
218 ret = pmbus_read_byte_data(client, page, reg);
221 data->access = ktime_get();
226 static int zl6100_write_word_data(struct i2c_client *client, int page, int reg,
229 const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
230 struct zl6100_data *data = to_zl6100_data(info);
237 case PMBUS_VIRT_VMON_OV_WARN_LIMIT:
238 word = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(word) * 10, 9));
239 vreg = MFR_VMON_OV_FAULT_LIMIT;
240 pmbus_clear_cache(client);
242 case PMBUS_VIRT_VMON_OV_FAULT_LIMIT:
243 vreg = MFR_VMON_OV_FAULT_LIMIT;
244 pmbus_clear_cache(client);
246 case PMBUS_VIRT_VMON_UV_WARN_LIMIT:
247 word = zl6100_d2l(DIV_ROUND_CLOSEST(zl6100_l2d(word) * 10, 11));
248 vreg = MFR_VMON_UV_FAULT_LIMIT;
249 pmbus_clear_cache(client);
251 case PMBUS_VIRT_VMON_UV_FAULT_LIMIT:
252 vreg = MFR_VMON_UV_FAULT_LIMIT;
253 pmbus_clear_cache(client);
256 if (reg >= PMBUS_VIRT_BASE)
262 ret = pmbus_write_word_data(client, page, vreg, word);
263 data->access = ktime_get();
268 static int zl6100_write_byte(struct i2c_client *client, int page, u8 value)
270 const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
271 struct zl6100_data *data = to_zl6100_data(info);
278 ret = pmbus_write_byte(client, page, value);
279 data->access = ktime_get();
284 static const struct i2c_device_id zl6100_id[] = {
302 MODULE_DEVICE_TABLE(i2c, zl6100_id);
304 static int zl6100_probe(struct i2c_client *client)
307 struct zl6100_data *data;
308 struct pmbus_driver_info *info;
309 u8 device_id[I2C_SMBUS_BLOCK_MAX + 1];
310 const struct i2c_device_id *mid;
312 if (!i2c_check_functionality(client->adapter,
313 I2C_FUNC_SMBUS_READ_WORD_DATA
314 | I2C_FUNC_SMBUS_READ_BLOCK_DATA))
317 ret = i2c_smbus_read_block_data(client, ZL6100_DEVICE_ID,
320 dev_err(&client->dev, "Failed to read device ID\n");
323 device_id[ret] = '\0';
324 dev_info(&client->dev, "Device ID %s\n", device_id);
327 for (mid = zl6100_id; mid->name[0]; mid++) {
328 if (!strncasecmp(mid->name, device_id, strlen(mid->name)))
332 dev_err(&client->dev, "Unsupported device\n");
335 if (strcmp(client->name, mid->name) != 0)
336 dev_notice(&client->dev,
337 "Device mismatch: Configured %s, detected %s\n",
338 client->name, mid->name);
340 data = devm_kzalloc(&client->dev, sizeof(struct zl6100_data),
345 data->id = mid->driver_data;
348 * According to information from the chip vendor, all currently
349 * supported chips are known to require a wait time between I2C
355 * Since there was a direct I2C device access above, wait before
356 * accessing the chip again.
358 data->access = ktime_get();
364 info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
365 | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
366 | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
367 | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
370 * ZL2004, ZL9101M, and ZL9117M support monitoring an extra voltage
371 * (VMON for ZL2004, VDRV for ZL9101M and ZL9117M). Report it as vmon.
373 if (data->id == zl2004 || data->id == zl9101 || data->id == zl9117)
374 info->func[0] |= PMBUS_HAVE_VMON | PMBUS_HAVE_STATUS_VMON;
376 ret = i2c_smbus_read_word_data(client, ZL6100_MFR_CONFIG);
380 if (ret & ZL6100_MFR_XTEMP_ENABLE)
381 info->func[0] |= PMBUS_HAVE_TEMP2;
383 data->access = ktime_get();
386 info->read_word_data = zl6100_read_word_data;
387 info->read_byte_data = zl6100_read_byte_data;
388 info->write_word_data = zl6100_write_word_data;
389 info->write_byte = zl6100_write_byte;
391 return pmbus_do_probe(client, info);
394 static struct i2c_driver zl6100_driver = {
398 .probe_new = zl6100_probe,
399 .remove = pmbus_do_remove,
400 .id_table = zl6100_id,
403 module_i2c_driver(zl6100_driver);
405 MODULE_AUTHOR("Guenter Roeck");
406 MODULE_DESCRIPTION("PMBus driver for ZL6100 and compatibles");
407 MODULE_LICENSE("GPL");