xref: /openbmc/linux/drivers/regulator/lp8755.c (revision e4d48f64)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * LP8755 High Performance Power Management Unit : System Interface Driver
4  * (based on rev. 0.26)
5  * Copyright 2012 Texas Instruments
6  *
7  * Author: Daniel(Geon Si) Jeong <daniel.jeong@ti.com>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/i2c.h>
13 #include <linux/err.h>
14 #include <linux/irq.h>
15 #include <linux/interrupt.h>
16 #include <linux/regmap.h>
17 #include <linux/uaccess.h>
18 #include <linux/regulator/driver.h>
19 #include <linux/regulator/machine.h>
20 #include <linux/platform_data/lp8755.h>
21 
22 #define LP8755_REG_BUCK0	0x00
23 #define LP8755_REG_BUCK1	0x03
24 #define LP8755_REG_BUCK2	0x04
25 #define LP8755_REG_BUCK3	0x01
26 #define LP8755_REG_BUCK4	0x05
27 #define LP8755_REG_BUCK5	0x02
28 #define LP8755_REG_MAX		0xFF
29 
30 #define LP8755_BUCK_EN_M	BIT(7)
31 #define LP8755_BUCK_LINEAR_OUT_MAX	0x76
32 #define LP8755_BUCK_VOUT_M	0x7F
33 
34 struct lp8755_mphase {
35 	int nreg;
36 	int buck_num[LP8755_BUCK_MAX];
37 };
38 
39 struct lp8755_chip {
40 	struct device *dev;
41 	struct regmap *regmap;
42 	struct lp8755_platform_data *pdata;
43 
44 	int irq;
45 	unsigned int irqmask;
46 
47 	int mphase;
48 	struct regulator_dev *rdev[LP8755_BUCK_MAX];
49 };
50 
lp8755_buck_enable_time(struct regulator_dev * rdev)51 static int lp8755_buck_enable_time(struct regulator_dev *rdev)
52 {
53 	int ret;
54 	unsigned int regval;
55 	enum lp8755_bucks id = rdev_get_id(rdev);
56 
57 	ret = regmap_read(rdev->regmap, 0x12 + id, &regval);
58 	if (ret < 0) {
59 		dev_err(&rdev->dev, "i2c access error %s\n", __func__);
60 		return ret;
61 	}
62 	return (regval & 0xff) * 100;
63 }
64 
lp8755_buck_set_mode(struct regulator_dev * rdev,unsigned int mode)65 static int lp8755_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
66 {
67 	int ret;
68 	unsigned int regbval = 0x0;
69 	enum lp8755_bucks id = rdev_get_id(rdev);
70 	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
71 
72 	switch (mode) {
73 	case REGULATOR_MODE_FAST:
74 		/* forced pwm mode */
75 		regbval = (0x01 << id);
76 		break;
77 	case REGULATOR_MODE_NORMAL:
78 		/* enable automatic pwm/pfm mode */
79 		ret = regmap_update_bits(rdev->regmap, 0x08 + id, 0x20, 0x00);
80 		if (ret < 0)
81 			goto err_i2c;
82 		break;
83 	case REGULATOR_MODE_IDLE:
84 		/* enable automatic pwm/pfm/lppfm mode */
85 		ret = regmap_update_bits(rdev->regmap, 0x08 + id, 0x20, 0x20);
86 		if (ret < 0)
87 			goto err_i2c;
88 
89 		ret = regmap_update_bits(rdev->regmap, 0x10, 0x01, 0x01);
90 		if (ret < 0)
91 			goto err_i2c;
92 		break;
93 	default:
94 		dev_err(pchip->dev, "Not supported buck mode %s\n", __func__);
95 		/* forced pwm mode */
96 		regbval = (0x01 << id);
97 	}
98 
99 	ret = regmap_update_bits(rdev->regmap, 0x06, 0x01 << id, regbval);
100 	if (ret < 0)
101 		goto err_i2c;
102 	return ret;
103 err_i2c:
104 	dev_err(&rdev->dev, "i2c access error %s\n", __func__);
105 	return ret;
106 }
107 
lp8755_buck_get_mode(struct regulator_dev * rdev)108 static unsigned int lp8755_buck_get_mode(struct regulator_dev *rdev)
109 {
110 	int ret;
111 	unsigned int regval;
112 	enum lp8755_bucks id = rdev_get_id(rdev);
113 
114 	ret = regmap_read(rdev->regmap, 0x06, &regval);
115 	if (ret < 0)
116 		goto err_i2c;
117 
118 	/* mode fast means forced pwm mode */
119 	if (regval & (0x01 << id))
120 		return REGULATOR_MODE_FAST;
121 
122 	ret = regmap_read(rdev->regmap, 0x08 + id, &regval);
123 	if (ret < 0)
124 		goto err_i2c;
125 
126 	/* mode idle means automatic pwm/pfm/lppfm mode */
127 	if (regval & 0x20)
128 		return REGULATOR_MODE_IDLE;
129 
130 	/* mode normal means automatic pwm/pfm mode */
131 	return REGULATOR_MODE_NORMAL;
132 
133 err_i2c:
134 	dev_err(&rdev->dev, "i2c access error %s\n", __func__);
135 	return 0;
136 }
137 
138 static const unsigned int lp8755_buck_ramp_table[] = {
139 	30000, 15000, 7500, 3800, 1900, 940, 470, 230
140 };
141 
142 static const struct regulator_ops lp8755_buck_ops = {
143 	.map_voltage = regulator_map_voltage_linear,
144 	.list_voltage = regulator_list_voltage_linear,
145 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
146 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
147 	.enable = regulator_enable_regmap,
148 	.disable = regulator_disable_regmap,
149 	.is_enabled = regulator_is_enabled_regmap,
150 	.enable_time = lp8755_buck_enable_time,
151 	.set_mode = lp8755_buck_set_mode,
152 	.get_mode = lp8755_buck_get_mode,
153 	.set_ramp_delay = regulator_set_ramp_delay_regmap,
154 };
155 
156 #define lp8755_rail(_id) "lp8755_buck"#_id
157 #define lp8755_buck_init(_id)\
158 {\
159 	.constraints = {\
160 		.name = lp8755_rail(_id),\
161 		.valid_ops_mask = REGULATOR_CHANGE_VOLTAGE,\
162 		.min_uV = 500000,\
163 		.max_uV = 1675000,\
164 	},\
165 }
166 
167 static struct regulator_init_data lp8755_reg_default[LP8755_BUCK_MAX] = {
168 	[LP8755_BUCK0] = lp8755_buck_init(0),
169 	[LP8755_BUCK1] = lp8755_buck_init(1),
170 	[LP8755_BUCK2] = lp8755_buck_init(2),
171 	[LP8755_BUCK3] = lp8755_buck_init(3),
172 	[LP8755_BUCK4] = lp8755_buck_init(4),
173 	[LP8755_BUCK5] = lp8755_buck_init(5),
174 };
175 
176 static const struct lp8755_mphase mphase_buck[MPHASE_CONF_MAX] = {
177 	{ 3, { LP8755_BUCK0, LP8755_BUCK3, LP8755_BUCK5 } },
178 	{ 6, { LP8755_BUCK0, LP8755_BUCK1, LP8755_BUCK2, LP8755_BUCK3,
179 	       LP8755_BUCK4, LP8755_BUCK5 } },
180 	{ 5, { LP8755_BUCK0, LP8755_BUCK2, LP8755_BUCK3, LP8755_BUCK4,
181 	       LP8755_BUCK5} },
182 	{ 4, { LP8755_BUCK0, LP8755_BUCK3, LP8755_BUCK4, LP8755_BUCK5} },
183 	{ 3, { LP8755_BUCK0, LP8755_BUCK4, LP8755_BUCK5} },
184 	{ 2, { LP8755_BUCK0, LP8755_BUCK5} },
185 	{ 1, { LP8755_BUCK0} },
186 	{ 2, { LP8755_BUCK0, LP8755_BUCK3} },
187 	{ 4, { LP8755_BUCK0, LP8755_BUCK2, LP8755_BUCK3, LP8755_BUCK5} },
188 };
189 
lp8755_init_data(struct lp8755_chip * pchip)190 static int lp8755_init_data(struct lp8755_chip *pchip)
191 {
192 	unsigned int regval;
193 	int ret, icnt, buck_num;
194 	struct lp8755_platform_data *pdata = pchip->pdata;
195 
196 	/* read back  muti-phase configuration */
197 	ret = regmap_read(pchip->regmap, 0x3D, &regval);
198 	if (ret < 0)
199 		goto out_i2c_error;
200 	pchip->mphase = regval & 0x0F;
201 
202 	/* set default data based on multi-phase config */
203 	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++) {
204 		buck_num = mphase_buck[pchip->mphase].buck_num[icnt];
205 		pdata->buck_data[buck_num] = &lp8755_reg_default[buck_num];
206 	}
207 	return ret;
208 
209 out_i2c_error:
210 	dev_err(pchip->dev, "i2c access error %s\n", __func__);
211 	return ret;
212 }
213 
214 #define lp8755_buck_desc(_id)\
215 {\
216 	.name = lp8755_rail(_id),\
217 	.id   = LP8755_BUCK##_id,\
218 	.ops  = &lp8755_buck_ops,\
219 	.n_voltages = LP8755_BUCK_LINEAR_OUT_MAX+1,\
220 	.uV_step = 10000,\
221 	.min_uV = 500000,\
222 	.type = REGULATOR_VOLTAGE,\
223 	.owner = THIS_MODULE,\
224 	.enable_reg = LP8755_REG_BUCK##_id,\
225 	.enable_mask = LP8755_BUCK_EN_M,\
226 	.vsel_reg = LP8755_REG_BUCK##_id,\
227 	.vsel_mask = LP8755_BUCK_VOUT_M,\
228 	.ramp_reg = (LP8755_BUCK##_id) + 0x7,\
229 	.ramp_mask = 0x7,\
230 	.ramp_delay_table = lp8755_buck_ramp_table,\
231 	.n_ramp_values = ARRAY_SIZE(lp8755_buck_ramp_table),\
232 }
233 
234 static const struct regulator_desc lp8755_regulators[] = {
235 	lp8755_buck_desc(0),
236 	lp8755_buck_desc(1),
237 	lp8755_buck_desc(2),
238 	lp8755_buck_desc(3),
239 	lp8755_buck_desc(4),
240 	lp8755_buck_desc(5),
241 };
242 
lp8755_regulator_init(struct lp8755_chip * pchip)243 static int lp8755_regulator_init(struct lp8755_chip *pchip)
244 {
245 	int ret, icnt, buck_num;
246 	struct lp8755_platform_data *pdata = pchip->pdata;
247 	struct regulator_config rconfig = { };
248 
249 	rconfig.regmap = pchip->regmap;
250 	rconfig.dev = pchip->dev;
251 	rconfig.driver_data = pchip;
252 
253 	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++) {
254 		buck_num = mphase_buck[pchip->mphase].buck_num[icnt];
255 		rconfig.init_data = pdata->buck_data[buck_num];
256 		rconfig.of_node = pchip->dev->of_node;
257 		pchip->rdev[buck_num] =
258 		    devm_regulator_register(pchip->dev,
259 				    &lp8755_regulators[buck_num], &rconfig);
260 		if (IS_ERR(pchip->rdev[buck_num])) {
261 			ret = PTR_ERR(pchip->rdev[buck_num]);
262 			pchip->rdev[buck_num] = NULL;
263 			dev_err(pchip->dev, "regulator init failed: buck %d\n",
264 				buck_num);
265 			return ret;
266 		}
267 	}
268 
269 	return 0;
270 }
271 
lp8755_irq_handler(int irq,void * data)272 static irqreturn_t lp8755_irq_handler(int irq, void *data)
273 {
274 	int ret, icnt;
275 	unsigned int flag0, flag1;
276 	struct lp8755_chip *pchip = data;
277 
278 	/* read flag0 register */
279 	ret = regmap_read(pchip->regmap, 0x0D, &flag0);
280 	if (ret < 0)
281 		goto err_i2c;
282 	/* clear flag register to pull up int. pin */
283 	ret = regmap_write(pchip->regmap, 0x0D, 0x00);
284 	if (ret < 0)
285 		goto err_i2c;
286 
287 	/* sent power fault detection event to specific regulator */
288 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
289 		if ((flag0 & (0x4 << icnt))
290 		    && (pchip->irqmask & (0x04 << icnt))
291 		    && (pchip->rdev[icnt] != NULL)) {
292 			regulator_notifier_call_chain(pchip->rdev[icnt],
293 						      LP8755_EVENT_PWR_FAULT,
294 						      NULL);
295 		}
296 
297 	/* read flag1 register */
298 	ret = regmap_read(pchip->regmap, 0x0E, &flag1);
299 	if (ret < 0)
300 		goto err_i2c;
301 	/* clear flag register to pull up int. pin */
302 	ret = regmap_write(pchip->regmap, 0x0E, 0x00);
303 	if (ret < 0)
304 		goto err_i2c;
305 
306 	/* send OCP event to all regulator devices */
307 	if ((flag1 & 0x01) && (pchip->irqmask & 0x01))
308 		for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
309 			if (pchip->rdev[icnt] != NULL) {
310 				regulator_notifier_call_chain(pchip->rdev[icnt],
311 							      LP8755_EVENT_OCP,
312 							      NULL);
313 			}
314 
315 	/* send OVP event to all regulator devices */
316 	if ((flag1 & 0x02) && (pchip->irqmask & 0x02))
317 		for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
318 			if (pchip->rdev[icnt] != NULL) {
319 				regulator_notifier_call_chain(pchip->rdev[icnt],
320 							      LP8755_EVENT_OVP,
321 							      NULL);
322 			}
323 	return IRQ_HANDLED;
324 
325 err_i2c:
326 	dev_err(pchip->dev, "i2c access error %s\n", __func__);
327 	return IRQ_NONE;
328 }
329 
lp8755_int_config(struct lp8755_chip * pchip)330 static int lp8755_int_config(struct lp8755_chip *pchip)
331 {
332 	int ret;
333 	unsigned int regval;
334 
335 	if (pchip->irq == 0) {
336 		dev_warn(pchip->dev, "not use interrupt : %s\n", __func__);
337 		return 0;
338 	}
339 
340 	ret = regmap_read(pchip->regmap, 0x0F, &regval);
341 	if (ret < 0) {
342 		dev_err(pchip->dev, "i2c access error %s\n", __func__);
343 		return ret;
344 	}
345 
346 	pchip->irqmask = regval;
347 	return devm_request_threaded_irq(pchip->dev, pchip->irq, NULL,
348 					 lp8755_irq_handler,
349 					 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
350 					 "lp8755-irq", pchip);
351 }
352 
353 static const struct regmap_config lp8755_regmap = {
354 	.reg_bits = 8,
355 	.val_bits = 8,
356 	.max_register = LP8755_REG_MAX,
357 };
358 
lp8755_probe(struct i2c_client * client)359 static int lp8755_probe(struct i2c_client *client)
360 {
361 	int ret, icnt;
362 	struct lp8755_chip *pchip;
363 	struct lp8755_platform_data *pdata = dev_get_platdata(&client->dev);
364 
365 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
366 		dev_err(&client->dev, "i2c functionality check fail.\n");
367 		return -EOPNOTSUPP;
368 	}
369 
370 	pchip = devm_kzalloc(&client->dev,
371 			     sizeof(struct lp8755_chip), GFP_KERNEL);
372 	if (!pchip)
373 		return -ENOMEM;
374 
375 	pchip->dev = &client->dev;
376 	pchip->regmap = devm_regmap_init_i2c(client, &lp8755_regmap);
377 	if (IS_ERR(pchip->regmap)) {
378 		ret = PTR_ERR(pchip->regmap);
379 		dev_err(&client->dev, "fail to allocate regmap %d\n", ret);
380 		return ret;
381 	}
382 	i2c_set_clientdata(client, pchip);
383 
384 	if (pdata != NULL) {
385 		pchip->pdata = pdata;
386 		pchip->mphase = pdata->mphase;
387 	} else {
388 		pchip->pdata = devm_kzalloc(pchip->dev,
389 					    sizeof(struct lp8755_platform_data),
390 					    GFP_KERNEL);
391 		if (!pchip->pdata)
392 			return -ENOMEM;
393 		ret = lp8755_init_data(pchip);
394 		if (ret < 0) {
395 			dev_err(&client->dev, "fail to initialize chip\n");
396 			return ret;
397 		}
398 	}
399 
400 	ret = lp8755_regulator_init(pchip);
401 	if (ret < 0) {
402 		dev_err(&client->dev, "fail to initialize regulators\n");
403 		goto err;
404 	}
405 
406 	pchip->irq = client->irq;
407 	ret = lp8755_int_config(pchip);
408 	if (ret < 0) {
409 		dev_err(&client->dev, "fail to irq config\n");
410 		goto err;
411 	}
412 
413 	return ret;
414 
415 err:
416 	/* output disable */
417 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
418 		regmap_write(pchip->regmap, icnt, 0x00);
419 
420 	return ret;
421 }
422 
lp8755_remove(struct i2c_client * client)423 static void lp8755_remove(struct i2c_client *client)
424 {
425 	int icnt;
426 	struct lp8755_chip *pchip = i2c_get_clientdata(client);
427 
428 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
429 		regmap_write(pchip->regmap, icnt, 0x00);
430 }
431 
432 static const struct i2c_device_id lp8755_id[] = {
433 	{LP8755_NAME, 0},
434 	{}
435 };
436 
437 MODULE_DEVICE_TABLE(i2c, lp8755_id);
438 
439 static struct i2c_driver lp8755_i2c_driver = {
440 	.driver = {
441 		   .name = LP8755_NAME,
442 		   .probe_type = PROBE_PREFER_ASYNCHRONOUS,
443 		   },
444 	.probe = lp8755_probe,
445 	.remove = lp8755_remove,
446 	.id_table = lp8755_id,
447 };
448 
lp8755_init(void)449 static int __init lp8755_init(void)
450 {
451 	return i2c_add_driver(&lp8755_i2c_driver);
452 }
453 
454 subsys_initcall(lp8755_init);
455 
lp8755_exit(void)456 static void __exit lp8755_exit(void)
457 {
458 	i2c_del_driver(&lp8755_i2c_driver);
459 }
460 
461 module_exit(lp8755_exit);
462 
463 MODULE_DESCRIPTION("Texas Instruments lp8755 driver");
464 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
465 MODULE_LICENSE("GPL v2");
466