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/gpio.h>
17 #include <linux/regmap.h>
18 #include <linux/uaccess.h>
19 #include <linux/regulator/driver.h>
20 #include <linux/regulator/machine.h>
21 #include <linux/platform_data/lp8755.h>
22 
23 #define LP8755_REG_BUCK0	0x00
24 #define LP8755_REG_BUCK1	0x03
25 #define LP8755_REG_BUCK2	0x04
26 #define LP8755_REG_BUCK3	0x01
27 #define LP8755_REG_BUCK4	0x05
28 #define LP8755_REG_BUCK5	0x02
29 #define LP8755_REG_MAX		0xFF
30 
31 #define LP8755_BUCK_EN_M	BIT(7)
32 #define LP8755_BUCK_LINEAR_OUT_MAX	0x76
33 #define LP8755_BUCK_VOUT_M	0x7F
34 
35 struct lp8755_mphase {
36 	int nreg;
37 	int buck_num[LP8755_BUCK_MAX];
38 };
39 
40 struct lp8755_chip {
41 	struct device *dev;
42 	struct regmap *regmap;
43 	struct lp8755_platform_data *pdata;
44 
45 	int irq;
46 	unsigned int irqmask;
47 
48 	int mphase;
49 	struct regulator_dev *rdev[LP8755_BUCK_MAX];
50 };
51 
lp8755_buck_enable_time(struct regulator_dev * rdev)52 static int lp8755_buck_enable_time(struct regulator_dev *rdev)
53 {
54 	int ret;
55 	unsigned int regval;
56 	enum lp8755_bucks id = rdev_get_id(rdev);
57 
58 	ret = regmap_read(rdev->regmap, 0x12 + id, &regval);
59 	if (ret < 0) {
60 		dev_err(&rdev->dev, "i2c access error %s\n", __func__);
61 		return ret;
62 	}
63 	return (regval & 0xff) * 100;
64 }
65 
lp8755_buck_set_mode(struct regulator_dev * rdev,unsigned int mode)66 static int lp8755_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
67 {
68 	int ret;
69 	unsigned int regbval = 0x0;
70 	enum lp8755_bucks id = rdev_get_id(rdev);
71 	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
72 
73 	switch (mode) {
74 	case REGULATOR_MODE_FAST:
75 		/* forced pwm mode */
76 		regbval = (0x01 << id);
77 		break;
78 	case REGULATOR_MODE_NORMAL:
79 		/* enable automatic pwm/pfm mode */
80 		ret = regmap_update_bits(rdev->regmap, 0x08 + id, 0x20, 0x00);
81 		if (ret < 0)
82 			goto err_i2c;
83 		break;
84 	case REGULATOR_MODE_IDLE:
85 		/* enable automatic pwm/pfm/lppfm mode */
86 		ret = regmap_update_bits(rdev->regmap, 0x08 + id, 0x20, 0x20);
87 		if (ret < 0)
88 			goto err_i2c;
89 
90 		ret = regmap_update_bits(rdev->regmap, 0x10, 0x01, 0x01);
91 		if (ret < 0)
92 			goto err_i2c;
93 		break;
94 	default:
95 		dev_err(pchip->dev, "Not supported buck mode %s\n", __func__);
96 		/* forced pwm mode */
97 		regbval = (0x01 << id);
98 	}
99 
100 	ret = regmap_update_bits(rdev->regmap, 0x06, 0x01 << id, regbval);
101 	if (ret < 0)
102 		goto err_i2c;
103 	return ret;
104 err_i2c:
105 	dev_err(&rdev->dev, "i2c access error %s\n", __func__);
106 	return ret;
107 }
108 
lp8755_buck_get_mode(struct regulator_dev * rdev)109 static unsigned int lp8755_buck_get_mode(struct regulator_dev *rdev)
110 {
111 	int ret;
112 	unsigned int regval;
113 	enum lp8755_bucks id = rdev_get_id(rdev);
114 
115 	ret = regmap_read(rdev->regmap, 0x06, &regval);
116 	if (ret < 0)
117 		goto err_i2c;
118 
119 	/* mode fast means forced pwm mode */
120 	if (regval & (0x01 << id))
121 		return REGULATOR_MODE_FAST;
122 
123 	ret = regmap_read(rdev->regmap, 0x08 + id, &regval);
124 	if (ret < 0)
125 		goto err_i2c;
126 
127 	/* mode idle means automatic pwm/pfm/lppfm mode */
128 	if (regval & 0x20)
129 		return REGULATOR_MODE_IDLE;
130 
131 	/* mode normal means automatic pwm/pfm mode */
132 	return REGULATOR_MODE_NORMAL;
133 
134 err_i2c:
135 	dev_err(&rdev->dev, "i2c access error %s\n", __func__);
136 	return 0;
137 }
138 
139 static const unsigned int lp8755_buck_ramp_table[] = {
140 	30000, 15000, 7500, 3800, 1900, 940, 470, 230
141 };
142 
143 static const struct regulator_ops lp8755_buck_ops = {
144 	.map_voltage = regulator_map_voltage_linear,
145 	.list_voltage = regulator_list_voltage_linear,
146 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
147 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
148 	.enable = regulator_enable_regmap,
149 	.disable = regulator_disable_regmap,
150 	.is_enabled = regulator_is_enabled_regmap,
151 	.enable_time = lp8755_buck_enable_time,
152 	.set_mode = lp8755_buck_set_mode,
153 	.get_mode = lp8755_buck_get_mode,
154 	.set_ramp_delay = regulator_set_ramp_delay_regmap,
155 };
156 
157 #define lp8755_rail(_id) "lp8755_buck"#_id
158 #define lp8755_buck_init(_id)\
159 {\
160 	.constraints = {\
161 		.name = lp8755_rail(_id),\
162 		.valid_ops_mask = REGULATOR_CHANGE_VOLTAGE,\
163 		.min_uV = 500000,\
164 		.max_uV = 1675000,\
165 	},\
166 }
167 
168 static struct regulator_init_data lp8755_reg_default[LP8755_BUCK_MAX] = {
169 	[LP8755_BUCK0] = lp8755_buck_init(0),
170 	[LP8755_BUCK1] = lp8755_buck_init(1),
171 	[LP8755_BUCK2] = lp8755_buck_init(2),
172 	[LP8755_BUCK3] = lp8755_buck_init(3),
173 	[LP8755_BUCK4] = lp8755_buck_init(4),
174 	[LP8755_BUCK5] = lp8755_buck_init(5),
175 };
176 
177 static const struct lp8755_mphase mphase_buck[MPHASE_CONF_MAX] = {
178 	{ 3, { LP8755_BUCK0, LP8755_BUCK3, LP8755_BUCK5 } },
179 	{ 6, { LP8755_BUCK0, LP8755_BUCK1, LP8755_BUCK2, LP8755_BUCK3,
180 	       LP8755_BUCK4, LP8755_BUCK5 } },
181 	{ 5, { LP8755_BUCK0, LP8755_BUCK2, LP8755_BUCK3, LP8755_BUCK4,
182 	       LP8755_BUCK5} },
183 	{ 4, { LP8755_BUCK0, LP8755_BUCK3, LP8755_BUCK4, LP8755_BUCK5} },
184 	{ 3, { LP8755_BUCK0, LP8755_BUCK4, LP8755_BUCK5} },
185 	{ 2, { LP8755_BUCK0, LP8755_BUCK5} },
186 	{ 1, { LP8755_BUCK0} },
187 	{ 2, { LP8755_BUCK0, LP8755_BUCK3} },
188 	{ 4, { LP8755_BUCK0, LP8755_BUCK2, LP8755_BUCK3, LP8755_BUCK5} },
189 };
190 
lp8755_init_data(struct lp8755_chip * pchip)191 static int lp8755_init_data(struct lp8755_chip *pchip)
192 {
193 	unsigned int regval;
194 	int ret, icnt, buck_num;
195 	struct lp8755_platform_data *pdata = pchip->pdata;
196 
197 	/* read back  muti-phase configuration */
198 	ret = regmap_read(pchip->regmap, 0x3D, &regval);
199 	if (ret < 0)
200 		goto out_i2c_error;
201 	pchip->mphase = regval & 0x0F;
202 
203 	/* set default data based on multi-phase config */
204 	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++) {
205 		buck_num = mphase_buck[pchip->mphase].buck_num[icnt];
206 		pdata->buck_data[buck_num] = &lp8755_reg_default[buck_num];
207 	}
208 	return ret;
209 
210 out_i2c_error:
211 	dev_err(pchip->dev, "i2c access error %s\n", __func__);
212 	return ret;
213 }
214 
215 #define lp8755_buck_desc(_id)\
216 {\
217 	.name = lp8755_rail(_id),\
218 	.id   = LP8755_BUCK##_id,\
219 	.ops  = &lp8755_buck_ops,\
220 	.n_voltages = LP8755_BUCK_LINEAR_OUT_MAX+1,\
221 	.uV_step = 10000,\
222 	.min_uV = 500000,\
223 	.type = REGULATOR_VOLTAGE,\
224 	.owner = THIS_MODULE,\
225 	.enable_reg = LP8755_REG_BUCK##_id,\
226 	.enable_mask = LP8755_BUCK_EN_M,\
227 	.vsel_reg = LP8755_REG_BUCK##_id,\
228 	.vsel_mask = LP8755_BUCK_VOUT_M,\
229 	.ramp_reg = (LP8755_BUCK##_id) + 0x7,\
230 	.ramp_mask = 0x7,\
231 	.ramp_delay_table = lp8755_buck_ramp_table,\
232 	.n_ramp_values = ARRAY_SIZE(lp8755_buck_ramp_table),\
233 }
234 
235 static const struct regulator_desc lp8755_regulators[] = {
236 	lp8755_buck_desc(0),
237 	lp8755_buck_desc(1),
238 	lp8755_buck_desc(2),
239 	lp8755_buck_desc(3),
240 	lp8755_buck_desc(4),
241 	lp8755_buck_desc(5),
242 };
243 
lp8755_regulator_init(struct lp8755_chip * pchip)244 static int lp8755_regulator_init(struct lp8755_chip *pchip)
245 {
246 	int ret, icnt, buck_num;
247 	struct lp8755_platform_data *pdata = pchip->pdata;
248 	struct regulator_config rconfig = { };
249 
250 	rconfig.regmap = pchip->regmap;
251 	rconfig.dev = pchip->dev;
252 	rconfig.driver_data = pchip;
253 
254 	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++) {
255 		buck_num = mphase_buck[pchip->mphase].buck_num[icnt];
256 		rconfig.init_data = pdata->buck_data[buck_num];
257 		rconfig.of_node = pchip->dev->of_node;
258 		pchip->rdev[buck_num] =
259 		    devm_regulator_register(pchip->dev,
260 				    &lp8755_regulators[buck_num], &rconfig);
261 		if (IS_ERR(pchip->rdev[buck_num])) {
262 			ret = PTR_ERR(pchip->rdev[buck_num]);
263 			pchip->rdev[buck_num] = NULL;
264 			dev_err(pchip->dev, "regulator init failed: buck %d\n",
265 				buck_num);
266 			return ret;
267 		}
268 	}
269 
270 	return 0;
271 }
272 
lp8755_irq_handler(int irq,void * data)273 static irqreturn_t lp8755_irq_handler(int irq, void *data)
274 {
275 	int ret, icnt;
276 	unsigned int flag0, flag1;
277 	struct lp8755_chip *pchip = data;
278 
279 	/* read flag0 register */
280 	ret = regmap_read(pchip->regmap, 0x0D, &flag0);
281 	if (ret < 0)
282 		goto err_i2c;
283 	/* clear flag register to pull up int. pin */
284 	ret = regmap_write(pchip->regmap, 0x0D, 0x00);
285 	if (ret < 0)
286 		goto err_i2c;
287 
288 	/* sent power fault detection event to specific regulator */
289 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
290 		if ((flag0 & (0x4 << icnt))
291 		    && (pchip->irqmask & (0x04 << icnt))
292 		    && (pchip->rdev[icnt] != NULL)) {
293 			regulator_notifier_call_chain(pchip->rdev[icnt],
294 						      LP8755_EVENT_PWR_FAULT,
295 						      NULL);
296 		}
297 
298 	/* read flag1 register */
299 	ret = regmap_read(pchip->regmap, 0x0E, &flag1);
300 	if (ret < 0)
301 		goto err_i2c;
302 	/* clear flag register to pull up int. pin */
303 	ret = regmap_write(pchip->regmap, 0x0E, 0x00);
304 	if (ret < 0)
305 		goto err_i2c;
306 
307 	/* send OCP event to all regulator devices */
308 	if ((flag1 & 0x01) && (pchip->irqmask & 0x01))
309 		for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
310 			if (pchip->rdev[icnt] != NULL) {
311 				regulator_notifier_call_chain(pchip->rdev[icnt],
312 							      LP8755_EVENT_OCP,
313 							      NULL);
314 			}
315 
316 	/* send OVP event to all regulator devices */
317 	if ((flag1 & 0x02) && (pchip->irqmask & 0x02))
318 		for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
319 			if (pchip->rdev[icnt] != NULL) {
320 				regulator_notifier_call_chain(pchip->rdev[icnt],
321 							      LP8755_EVENT_OVP,
322 							      NULL);
323 			}
324 	return IRQ_HANDLED;
325 
326 err_i2c:
327 	dev_err(pchip->dev, "i2c access error %s\n", __func__);
328 	return IRQ_NONE;
329 }
330 
lp8755_int_config(struct lp8755_chip * pchip)331 static int lp8755_int_config(struct lp8755_chip *pchip)
332 {
333 	int ret;
334 	unsigned int regval;
335 
336 	if (pchip->irq == 0) {
337 		dev_warn(pchip->dev, "not use interrupt : %s\n", __func__);
338 		return 0;
339 	}
340 
341 	ret = regmap_read(pchip->regmap, 0x0F, &regval);
342 	if (ret < 0) {
343 		dev_err(pchip->dev, "i2c access error %s\n", __func__);
344 		return ret;
345 	}
346 
347 	pchip->irqmask = regval;
348 	return devm_request_threaded_irq(pchip->dev, pchip->irq, NULL,
349 					 lp8755_irq_handler,
350 					 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
351 					 "lp8755-irq", pchip);
352 }
353 
354 static const struct regmap_config lp8755_regmap = {
355 	.reg_bits = 8,
356 	.val_bits = 8,
357 	.max_register = LP8755_REG_MAX,
358 };
359 
lp8755_probe(struct i2c_client * client,const struct i2c_device_id * id)360 static int lp8755_probe(struct i2c_client *client,
361 			const struct i2c_device_id *id)
362 {
363 	int ret, icnt;
364 	struct lp8755_chip *pchip;
365 	struct lp8755_platform_data *pdata = dev_get_platdata(&client->dev);
366 
367 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
368 		dev_err(&client->dev, "i2c functionality check fail.\n");
369 		return -EOPNOTSUPP;
370 	}
371 
372 	pchip = devm_kzalloc(&client->dev,
373 			     sizeof(struct lp8755_chip), GFP_KERNEL);
374 	if (!pchip)
375 		return -ENOMEM;
376 
377 	pchip->dev = &client->dev;
378 	pchip->regmap = devm_regmap_init_i2c(client, &lp8755_regmap);
379 	if (IS_ERR(pchip->regmap)) {
380 		ret = PTR_ERR(pchip->regmap);
381 		dev_err(&client->dev, "fail to allocate regmap %d\n", ret);
382 		return ret;
383 	}
384 	i2c_set_clientdata(client, pchip);
385 
386 	if (pdata != NULL) {
387 		pchip->pdata = pdata;
388 		pchip->mphase = pdata->mphase;
389 	} else {
390 		pchip->pdata = devm_kzalloc(pchip->dev,
391 					    sizeof(struct lp8755_platform_data),
392 					    GFP_KERNEL);
393 		if (!pchip->pdata)
394 			return -ENOMEM;
395 		ret = lp8755_init_data(pchip);
396 		if (ret < 0) {
397 			dev_err(&client->dev, "fail to initialize chip\n");
398 			return ret;
399 		}
400 	}
401 
402 	ret = lp8755_regulator_init(pchip);
403 	if (ret < 0) {
404 		dev_err(&client->dev, "fail to initialize regulators\n");
405 		goto err;
406 	}
407 
408 	pchip->irq = client->irq;
409 	ret = lp8755_int_config(pchip);
410 	if (ret < 0) {
411 		dev_err(&client->dev, "fail to irq config\n");
412 		goto err;
413 	}
414 
415 	return ret;
416 
417 err:
418 	/* output disable */
419 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
420 		regmap_write(pchip->regmap, icnt, 0x00);
421 
422 	return ret;
423 }
424 
lp8755_remove(struct i2c_client * client)425 static void lp8755_remove(struct i2c_client *client)
426 {
427 	int icnt;
428 	struct lp8755_chip *pchip = i2c_get_clientdata(client);
429 
430 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
431 		regmap_write(pchip->regmap, icnt, 0x00);
432 }
433 
434 static const struct i2c_device_id lp8755_id[] = {
435 	{LP8755_NAME, 0},
436 	{}
437 };
438 
439 MODULE_DEVICE_TABLE(i2c, lp8755_id);
440 
441 static struct i2c_driver lp8755_i2c_driver = {
442 	.driver = {
443 		   .name = LP8755_NAME,
444 		   },
445 	.probe = lp8755_probe,
446 	.remove = lp8755_remove,
447 	.id_table = lp8755_id,
448 };
449 
lp8755_init(void)450 static int __init lp8755_init(void)
451 {
452 	return i2c_add_driver(&lp8755_i2c_driver);
453 }
454 
455 subsys_initcall(lp8755_init);
456 
lp8755_exit(void)457 static void __exit lp8755_exit(void)
458 {
459 	i2c_del_driver(&lp8755_i2c_driver);
460 }
461 
462 module_exit(lp8755_exit);
463 
464 MODULE_DESCRIPTION("Texas Instruments lp8755 driver");
465 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
466 MODULE_LICENSE("GPL v2");
467