1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (c) 2019 five technologies GmbH
4 // Author: Markus Reichl <m.reichl@fivetechno.de>
5
6 #include <linux/module.h>
7 #include <linux/i2c.h>
8 #include <linux/of.h>
9 #include <linux/regulator/driver.h>
10 #include <linux/regmap.h>
11
12
13 #define VOL_MIN_IDX 0x00
14 #define VOL_MAX_IDX 0x7ff
15
16 /* Register definitions */
17 #define MP8859_VOUT_L_REG 0 //3 lo Bits
18 #define MP8859_VOUT_H_REG 1 //8 hi Bits
19 #define MP8859_VOUT_GO_REG 2
20 #define MP8859_IOUT_LIM_REG 3
21 #define MP8859_CTL1_REG 4
22 #define MP8859_CTL2_REG 5
23 #define MP8859_RESERVED1_REG 6
24 #define MP8859_RESERVED2_REG 7
25 #define MP8859_RESERVED3_REG 8
26 #define MP8859_STATUS_REG 9
27 #define MP8859_INTERRUPT_REG 0x0A
28 #define MP8859_MASK_REG 0x0B
29 #define MP8859_ID1_REG 0x0C
30 #define MP8859_MFR_ID_REG 0x27
31 #define MP8859_DEV_ID_REG 0x28
32 #define MP8859_IC_REV_REG 0x29
33
34 #define MP8859_MAX_REG 0x29
35
36 #define MP8859_GO_BIT 0x01
37
38 #define MP8859_IOUT_LIM_MASK 0x7f
39
40 #define MP8859_ENABLE_MASK 0x80
41 #define MP8859_DISCHG_EN_MASK 0x10
42 #define MP8859_MODE_MASK 0x08
43
44 #define MP8859_PG_MASK 0x80
45 #define MP8859_OTP_MASK 0x40
46 #define MP8859_OTW_MASK 0x20
47 #define MP8859_CC_CV_MASK 0x10
48
mp8859_set_voltage_sel(struct regulator_dev * rdev,unsigned int sel)49 static int mp8859_set_voltage_sel(struct regulator_dev *rdev, unsigned int sel)
50 {
51 int ret;
52
53 ret = regmap_write(rdev->regmap, MP8859_VOUT_L_REG, sel & 0x7);
54
55 if (ret)
56 return ret;
57 ret = regmap_write(rdev->regmap, MP8859_VOUT_H_REG, sel >> 3);
58
59 if (ret)
60 return ret;
61 ret = regmap_update_bits(rdev->regmap, MP8859_VOUT_GO_REG,
62 MP8859_GO_BIT, 1);
63 return ret;
64 }
65
mp8859_get_voltage_sel(struct regulator_dev * rdev)66 static int mp8859_get_voltage_sel(struct regulator_dev *rdev)
67 {
68 unsigned int val_tmp;
69 unsigned int val;
70 int ret;
71
72 ret = regmap_read(rdev->regmap, MP8859_VOUT_H_REG, &val_tmp);
73
74 if (ret)
75 return ret;
76 val = val_tmp << 3;
77
78 ret = regmap_read(rdev->regmap, MP8859_VOUT_L_REG, &val_tmp);
79
80 if (ret)
81 return ret;
82 val |= val_tmp & 0x07;
83 return val;
84 }
85
mp8859_set_voltage_time_sel(struct regulator_dev * rdev,unsigned int from,unsigned int to)86 static int mp8859_set_voltage_time_sel(struct regulator_dev *rdev,
87 unsigned int from, unsigned int to)
88 {
89 int change;
90
91 /* The voltage ramps at 1mV/uS, selectors are 10mV */
92 if (from > to)
93 change = from - to;
94 else
95 change = to - from;
96
97 return change * 10 * 1000;
98 }
99
mp8859_get_mode(struct regulator_dev * rdev)100 static unsigned int mp8859_get_mode(struct regulator_dev *rdev)
101 {
102 unsigned int val;
103 int ret;
104
105 ret = regmap_read(rdev->regmap, MP8859_CTL1_REG, &val);
106 if (ret != 0) {
107 dev_err(&rdev->dev, "Failed to read mode: %d\n", ret);
108 return 0;
109 }
110
111 if (val & MP8859_MODE_MASK)
112 return REGULATOR_MODE_FAST;
113 else
114 return REGULATOR_MODE_NORMAL;
115 }
116
mp8859_set_mode(struct regulator_dev * rdev,unsigned int mode)117 static int mp8859_set_mode(struct regulator_dev *rdev, unsigned int mode)
118 {
119 unsigned int val;
120
121 switch (mode) {
122 case REGULATOR_MODE_FAST:
123 val = MP8859_MODE_MASK;
124 break;
125 case REGULATOR_MODE_NORMAL:
126 val = 0;
127 break;
128 default:
129 return -EINVAL;
130 }
131
132 return regmap_update_bits(rdev->regmap, MP8859_CTL1_REG,
133 MP8859_MODE_MASK, val);
134 }
135
mp8859_set_current_limit(struct regulator_dev * rdev,int min_uA,int max_uA)136 static int mp8859_set_current_limit(struct regulator_dev *rdev,
137 int min_uA, int max_uA)
138 {
139 unsigned int cur_val, new_val;
140 int ret, i;
141
142 /* Steps of 50mA */
143 new_val = max_uA / 50000;
144 if (new_val > MP8859_IOUT_LIM_MASK)
145 return -EINVAL;
146 if (new_val == 0)
147 return -EINVAL;
148
149 /*
150 * If the regulator is limiting then ramp gradually as per
151 * datasheet, otherwise just set the value directly.
152 */
153 ret = regmap_read(rdev->regmap, MP8859_STATUS_REG, &cur_val);
154 if (ret != 0)
155 return ret;
156 if (!(cur_val & MP8859_CC_CV_MASK)) {
157 return regmap_update_bits(rdev->regmap, MP8859_IOUT_LIM_REG,
158 MP8859_IOUT_LIM_MASK, new_val);
159 }
160
161 ret = regmap_read(rdev->regmap, MP8859_IOUT_LIM_REG, &cur_val);
162 if (ret != 0)
163 return ret;
164
165 if (cur_val >= new_val) {
166 for (i = cur_val; i >= new_val; i--) {
167 ret = regmap_update_bits(rdev->regmap,
168 MP8859_IOUT_LIM_REG,
169 MP8859_IOUT_LIM_MASK,
170 cur_val - i);
171 if (ret != 0)
172 return ret;
173 }
174 } else {
175 for (i = cur_val; i <= new_val; i++) {
176 ret = regmap_update_bits(rdev->regmap,
177 MP8859_IOUT_LIM_REG,
178 MP8859_IOUT_LIM_MASK,
179 cur_val + i);
180 if (ret != 0)
181 return ret;
182 }
183 }
184
185 return 0;
186 }
187
mp8859_get_status(struct regulator_dev * rdev)188 static int mp8859_get_status(struct regulator_dev *rdev)
189 {
190 unsigned int val;
191 int ret;
192
193 /* Output status is only meaingful when enabled */
194 ret = regmap_read(rdev->regmap, MP8859_CTL1_REG, &val);
195 if (ret != 0)
196 return ret;
197 if (!(val & MP8859_ENABLE_MASK))
198 return REGULATOR_STATUS_UNDEFINED;
199
200 ret = regmap_read(rdev->regmap, MP8859_STATUS_REG, &val);
201 if (ret != 0)
202 return ret;
203
204 if (val & MP8859_PG_MASK)
205 return REGULATOR_STATUS_ON;
206 else
207 return REGULATOR_STATUS_ERROR;
208 }
209
mp8859_get_error_flags(struct regulator_dev * rdev,unsigned int * flags)210 static int mp8859_get_error_flags(struct regulator_dev *rdev,
211 unsigned int *flags)
212 {
213 unsigned int status, enabled;
214 int ret;
215
216 *flags = 0;
217
218 /* Output status is only meaingful when enabled */
219 ret = regmap_read(rdev->regmap, MP8859_CTL1_REG, &enabled);
220 if (ret != 0)
221 return ret;
222 enabled &= MP8859_ENABLE_MASK;
223
224 ret = regmap_read(rdev->regmap, MP8859_STATUS_REG, &status);
225 if (ret != 0)
226 return ret;
227
228 if (enabled && !(status & MP8859_PG_MASK))
229 status |= REGULATOR_ERROR_FAIL;
230 if (status & MP8859_OTP_MASK)
231 status |= REGULATOR_ERROR_OVER_TEMP;
232 if (status & MP8859_OTW_MASK)
233 status |= REGULATOR_ERROR_OVER_TEMP_WARN;
234 if (status & MP8859_CC_CV_MASK)
235 status |= REGULATOR_ERROR_OVER_CURRENT;
236
237 return 0;
238 }
239
240 static const struct linear_range mp8859_dcdc_ranges[] = {
241 REGULATOR_LINEAR_RANGE(0, VOL_MIN_IDX, VOL_MAX_IDX, 10000),
242 };
243
mp8859_readable(struct device * dev,unsigned int reg)244 static bool mp8859_readable(struct device *dev, unsigned int reg)
245 {
246 switch (reg) {
247 case MP8859_VOUT_L_REG:
248 case MP8859_VOUT_H_REG:
249 case MP8859_VOUT_GO_REG:
250 case MP8859_IOUT_LIM_REG:
251 case MP8859_CTL1_REG:
252 case MP8859_CTL2_REG:
253 case MP8859_STATUS_REG:
254 case MP8859_INTERRUPT_REG:
255 case MP8859_MASK_REG:
256 case MP8859_ID1_REG:
257 case MP8859_MFR_ID_REG:
258 case MP8859_DEV_ID_REG:
259 case MP8859_IC_REV_REG:
260 return true;
261 default:
262 return false;
263 }
264 }
265
mp8859_volatile(struct device * dev,unsigned int reg)266 static bool mp8859_volatile(struct device *dev, unsigned int reg)
267 {
268 switch (reg) {
269 case MP8859_VOUT_GO_REG:
270 case MP8859_STATUS_REG:
271 case MP8859_INTERRUPT_REG:
272 return true;
273 default:
274 return false;
275 }
276 }
277
278 static const struct regmap_config mp8859_regmap = {
279 .reg_bits = 8,
280 .val_bits = 8,
281 .max_register = MP8859_MAX_REG,
282 .cache_type = REGCACHE_MAPLE,
283 .readable_reg = mp8859_readable,
284 .volatile_reg = mp8859_volatile,
285 };
286
287 static const struct regulator_ops mp8859_ops = {
288 .set_voltage_sel = mp8859_set_voltage_sel,
289 .get_voltage_sel = mp8859_get_voltage_sel,
290 .list_voltage = regulator_list_voltage_linear_range,
291 .set_voltage_time_sel = mp8859_set_voltage_time_sel,
292 .enable = regulator_enable_regmap,
293 .disable = regulator_disable_regmap,
294 .is_enabled = regulator_is_enabled_regmap,
295 .set_mode = mp8859_set_mode,
296 .get_mode = mp8859_get_mode,
297 .set_active_discharge = regulator_set_active_discharge_regmap,
298 .set_current_limit = mp8859_set_current_limit,
299 .get_status = mp8859_get_status,
300 .get_error_flags = mp8859_get_error_flags,
301 };
302
303 static const struct regulator_desc mp8859_regulators[] = {
304 {
305 .id = 0,
306 .type = REGULATOR_VOLTAGE,
307 .name = "mp8859_dcdc",
308 .supply_name = "vin",
309 .of_match = of_match_ptr("mp8859_dcdc"),
310 .n_voltages = VOL_MAX_IDX + 1,
311 .linear_ranges = mp8859_dcdc_ranges,
312 .n_linear_ranges = 1,
313 .enable_reg = MP8859_CTL1_REG,
314 .enable_mask = MP8859_ENABLE_MASK,
315 .enable_val = MP8859_ENABLE_MASK,
316 .active_discharge_reg = MP8859_CTL1_REG,
317 .active_discharge_on = MP8859_DISCHG_EN_MASK,
318 .active_discharge_mask = MP8859_DISCHG_EN_MASK,
319 .ops = &mp8859_ops,
320 .owner = THIS_MODULE,
321 },
322 };
323
mp8859_i2c_probe(struct i2c_client * i2c)324 static int mp8859_i2c_probe(struct i2c_client *i2c)
325 {
326 int ret;
327 struct regulator_config config = {.dev = &i2c->dev};
328 struct regmap *regmap = devm_regmap_init_i2c(i2c, &mp8859_regmap);
329 struct regulator_dev *rdev;
330 unsigned int val, rev;
331
332 if (IS_ERR(regmap)) {
333 ret = PTR_ERR(regmap);
334 dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
335 return ret;
336 }
337
338 ret = regmap_read(regmap, MP8859_MFR_ID_REG, &val);
339 if (ret != 0) {
340 dev_err(&i2c->dev, "Failed to read manufacturer ID: %d\n", ret);
341 return ret;
342 }
343 if (val != 0x9) {
344 dev_err(&i2c->dev, "Manufacturer ID %x != 9\n", val);
345 return -EINVAL;
346 }
347
348 ret = regmap_read(regmap, MP8859_DEV_ID_REG, &val);
349 if (ret != 0) {
350 dev_err(&i2c->dev, "Failed to read device ID: %d\n", ret);
351 return ret;
352 }
353 if (val != 0x58) {
354 dev_err(&i2c->dev, "Manufacturer ID %x != 0x58\n", val);
355 return -EINVAL;
356 }
357
358 ret = regmap_read(regmap, MP8859_IC_REV_REG, &rev);
359 if (ret != 0) {
360 dev_err(&i2c->dev, "Failed to read device revision: %d\n", ret);
361 return ret;
362 }
363 ret = regmap_read(regmap, MP8859_ID1_REG, &val);
364 if (ret != 0) {
365 dev_err(&i2c->dev, "Failed to read device ID1: %d\n", ret);
366 return ret;
367 }
368 dev_info(&i2c->dev, "MP8859-%04d revision %d\n", val, rev);
369
370 rdev = devm_regulator_register(&i2c->dev, &mp8859_regulators[0],
371 &config);
372
373 if (IS_ERR(rdev)) {
374 ret = PTR_ERR(rdev);
375 dev_err(&i2c->dev, "failed to register %s: %d\n",
376 mp8859_regulators[0].name, ret);
377 return ret;
378 }
379 return 0;
380 }
381
382 static const struct of_device_id mp8859_dt_id[] __maybe_unused = {
383 {.compatible = "mps,mp8859"},
384 {},
385 };
386 MODULE_DEVICE_TABLE(of, mp8859_dt_id);
387
388 static const struct i2c_device_id mp8859_i2c_id[] = {
389 { "mp8859", },
390 { },
391 };
392 MODULE_DEVICE_TABLE(i2c, mp8859_i2c_id);
393
394 static struct i2c_driver mp8859_regulator_driver = {
395 .driver = {
396 .name = "mp8859",
397 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
398 .of_match_table = of_match_ptr(mp8859_dt_id),
399 },
400 .probe = mp8859_i2c_probe,
401 .id_table = mp8859_i2c_id,
402 };
403
404 module_i2c_driver(mp8859_regulator_driver);
405
406 MODULE_DESCRIPTION("Monolithic Power Systems MP8859 voltage regulator driver");
407 MODULE_AUTHOR("Markus Reichl <m.reichl@fivetechno.de>");
408 MODULE_LICENSE("GPL v2");
409