xref: /linux/drivers/regulator/mp8859.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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