1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * TI LP8788 MFD - buck regulator driver
4 *
5 * Copyright 2012 Texas Instruments
6 *
7 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
8 */
9
10#include <linux/module.h>
11#include <linux/slab.h>
12#include <linux/err.h>
13#include <linux/platform_device.h>
14#include <linux/regulator/driver.h>
15#include <linux/mfd/lp8788.h>
16#include <linux/gpio/consumer.h>
17
18/* register address */
19#define LP8788_EN_BUCK			0x0C
20#define LP8788_BUCK_DVS_SEL		0x1D
21#define LP8788_BUCK1_VOUT0		0x1E
22#define LP8788_BUCK1_VOUT1		0x1F
23#define LP8788_BUCK1_VOUT2		0x20
24#define LP8788_BUCK1_VOUT3		0x21
25#define LP8788_BUCK2_VOUT0		0x22
26#define LP8788_BUCK2_VOUT1		0x23
27#define LP8788_BUCK2_VOUT2		0x24
28#define LP8788_BUCK2_VOUT3		0x25
29#define LP8788_BUCK3_VOUT		0x26
30#define LP8788_BUCK4_VOUT		0x27
31#define LP8788_BUCK1_TIMESTEP		0x28
32#define LP8788_BUCK_PWM			0x2D
33
34/* mask/shift bits */
35#define LP8788_EN_BUCK1_M		BIT(0)	/* Addr 0Ch */
36#define LP8788_EN_BUCK2_M		BIT(1)
37#define LP8788_EN_BUCK3_M		BIT(2)
38#define LP8788_EN_BUCK4_M		BIT(3)
39#define LP8788_BUCK1_DVS_SEL_M		0x04	/* Addr 1Dh */
40#define LP8788_BUCK1_DVS_M		0x03
41#define LP8788_BUCK1_DVS_S		0
42#define LP8788_BUCK2_DVS_SEL_M		0x40
43#define LP8788_BUCK2_DVS_M		0x30
44#define LP8788_BUCK2_DVS_S		4
45#define LP8788_BUCK1_DVS_I2C		BIT(2)
46#define LP8788_BUCK2_DVS_I2C		BIT(6)
47#define LP8788_BUCK1_DVS_PIN		(0 << 2)
48#define LP8788_BUCK2_DVS_PIN		(0 << 6)
49#define LP8788_VOUT_M			0x1F	/* Addr 1Eh ~ 27h */
50#define LP8788_STARTUP_TIME_M		0xF8	/* Addr 28h ~ 2Bh */
51#define LP8788_STARTUP_TIME_S		3
52#define LP8788_FPWM_BUCK1_M		BIT(0)	/* Addr 2Dh */
53#define LP8788_FPWM_BUCK1_S		0
54#define LP8788_FPWM_BUCK2_M		BIT(1)
55#define LP8788_FPWM_BUCK2_S		1
56#define LP8788_FPWM_BUCK3_M		BIT(2)
57#define LP8788_FPWM_BUCK3_S		2
58#define LP8788_FPWM_BUCK4_M		BIT(3)
59#define LP8788_FPWM_BUCK4_S		3
60
61#define INVALID_ADDR			0xFF
62#define LP8788_FORCE_PWM		1
63#define LP8788_AUTO_PWM			0
64#define PIN_LOW				0
65#define PIN_HIGH			1
66#define ENABLE_TIME_USEC		32
67
68#define BUCK_FPWM_MASK(x)		(1 << (x))
69#define BUCK_FPWM_SHIFT(x)		(x)
70
71enum lp8788_dvs_state {
72	DVS_LOW  = 0,
73	DVS_HIGH = 1,
74};
75
76enum lp8788_dvs_mode {
77	REGISTER,
78	EXTPIN,
79};
80
81enum lp8788_buck_id {
82	BUCK1,
83	BUCK2,
84	BUCK3,
85	BUCK4,
86};
87
88struct lp8788_buck {
89	struct lp8788 *lp;
90	struct regulator_dev *regulator;
91	void *dvs;
92	struct gpio_desc *gpio1;
93	struct gpio_desc *gpio2; /* Only used on BUCK2 */
94};
95
96/* BUCK 1 ~ 4 voltage ranges */
97static const struct linear_range buck_volt_ranges[] = {
98	REGULATOR_LINEAR_RANGE(500000, 0, 0, 0),
99	REGULATOR_LINEAR_RANGE(800000, 1, 25, 50000),
100};
101
102static void lp8788_buck1_set_dvs(struct lp8788_buck *buck)
103{
104	struct lp8788_buck1_dvs *dvs = (struct lp8788_buck1_dvs *)buck->dvs;
105	enum lp8788_dvs_state pinstate;
106
107	if (!dvs)
108		return;
109
110	pinstate = dvs->vsel == DVS_SEL_V0 ? DVS_LOW : DVS_HIGH;
111	gpiod_set_value(buck->gpio1, pinstate);
112}
113
114static void lp8788_buck2_set_dvs(struct lp8788_buck *buck)
115{
116	struct lp8788_buck2_dvs *dvs = (struct lp8788_buck2_dvs *)buck->dvs;
117	enum lp8788_dvs_state pin1, pin2;
118
119	if (!dvs)
120		return;
121
122	switch (dvs->vsel) {
123	case DVS_SEL_V0:
124		pin1 = DVS_LOW;
125		pin2 = DVS_LOW;
126		break;
127	case DVS_SEL_V1:
128		pin1 = DVS_HIGH;
129		pin2 = DVS_LOW;
130		break;
131	case DVS_SEL_V2:
132		pin1 = DVS_LOW;
133		pin2 = DVS_HIGH;
134		break;
135	case DVS_SEL_V3:
136		pin1 = DVS_HIGH;
137		pin2 = DVS_HIGH;
138		break;
139	default:
140		return;
141	}
142
143	gpiod_set_value(buck->gpio1, pin1);
144	gpiod_set_value(buck->gpio2, pin2);
145}
146
147static void lp8788_set_dvs(struct lp8788_buck *buck, enum lp8788_buck_id id)
148{
149	switch (id) {
150	case BUCK1:
151		lp8788_buck1_set_dvs(buck);
152		break;
153	case BUCK2:
154		lp8788_buck2_set_dvs(buck);
155		break;
156	default:
157		break;
158	}
159}
160
161static enum lp8788_dvs_mode
162lp8788_get_buck_dvs_ctrl_mode(struct lp8788_buck *buck, enum lp8788_buck_id id)
163{
164	u8 val, mask;
165
166	switch (id) {
167	case BUCK1:
168		mask = LP8788_BUCK1_DVS_SEL_M;
169		break;
170	case BUCK2:
171		mask = LP8788_BUCK2_DVS_SEL_M;
172		break;
173	default:
174		return REGISTER;
175	}
176
177	lp8788_read_byte(buck->lp, LP8788_BUCK_DVS_SEL, &val);
178
179	return val & mask ? REGISTER : EXTPIN;
180}
181
182static bool lp8788_is_valid_buck_addr(u8 addr)
183{
184	switch (addr) {
185	case LP8788_BUCK1_VOUT0:
186	case LP8788_BUCK1_VOUT1:
187	case LP8788_BUCK1_VOUT2:
188	case LP8788_BUCK1_VOUT3:
189	case LP8788_BUCK2_VOUT0:
190	case LP8788_BUCK2_VOUT1:
191	case LP8788_BUCK2_VOUT2:
192	case LP8788_BUCK2_VOUT3:
193		return true;
194	default:
195		return false;
196	}
197}
198
199static u8 lp8788_select_buck_vout_addr(struct lp8788_buck *buck,
200					enum lp8788_buck_id id)
201{
202	enum lp8788_dvs_mode mode = lp8788_get_buck_dvs_ctrl_mode(buck, id);
203	u8 val, idx, addr;
204	int pin1, pin2;
205
206	switch (id) {
207	case BUCK1:
208		if (mode == EXTPIN) {
209			idx = gpiod_get_value(buck->gpio1);
210		} else {
211			lp8788_read_byte(buck->lp, LP8788_BUCK_DVS_SEL, &val);
212			idx = (val & LP8788_BUCK1_DVS_M) >> LP8788_BUCK1_DVS_S;
213		}
214		addr = LP8788_BUCK1_VOUT0 + idx;
215		break;
216	case BUCK2:
217		if (mode == EXTPIN) {
218			pin1 = gpiod_get_value(buck->gpio1);
219			pin2 = gpiod_get_value(buck->gpio2);
220
221			if (pin1 == PIN_LOW && pin2 == PIN_LOW)
222				idx = 0;
223			else if (pin1 == PIN_LOW && pin2 == PIN_HIGH)
224				idx = 2;
225			else if (pin1 == PIN_HIGH && pin2 == PIN_LOW)
226				idx = 1;
227			else
228				idx = 3;
229		} else {
230			lp8788_read_byte(buck->lp, LP8788_BUCK_DVS_SEL, &val);
231			idx = (val & LP8788_BUCK2_DVS_M) >> LP8788_BUCK2_DVS_S;
232		}
233		addr = LP8788_BUCK2_VOUT0 + idx;
234		break;
235	default:
236		goto err;
237	}
238
239	return addr;
240err:
241	return INVALID_ADDR;
242}
243
244static int lp8788_buck12_set_voltage_sel(struct regulator_dev *rdev,
245					unsigned selector)
246{
247	struct lp8788_buck *buck = rdev_get_drvdata(rdev);
248	enum lp8788_buck_id id = rdev_get_id(rdev);
249	u8 addr;
250
251	if (buck->dvs)
252		lp8788_set_dvs(buck, id);
253
254	addr = lp8788_select_buck_vout_addr(buck, id);
255	if (!lp8788_is_valid_buck_addr(addr))
256		return -EINVAL;
257
258	return lp8788_update_bits(buck->lp, addr, LP8788_VOUT_M, selector);
259}
260
261static int lp8788_buck12_get_voltage_sel(struct regulator_dev *rdev)
262{
263	struct lp8788_buck *buck = rdev_get_drvdata(rdev);
264	enum lp8788_buck_id id = rdev_get_id(rdev);
265	int ret;
266	u8 val, addr;
267
268	addr = lp8788_select_buck_vout_addr(buck, id);
269	if (!lp8788_is_valid_buck_addr(addr))
270		return -EINVAL;
271
272	ret = lp8788_read_byte(buck->lp, addr, &val);
273	if (ret)
274		return ret;
275
276	return val & LP8788_VOUT_M;
277}
278
279static int lp8788_buck_enable_time(struct regulator_dev *rdev)
280{
281	struct lp8788_buck *buck = rdev_get_drvdata(rdev);
282	enum lp8788_buck_id id = rdev_get_id(rdev);
283	u8 val, addr = LP8788_BUCK1_TIMESTEP + id;
284
285	if (lp8788_read_byte(buck->lp, addr, &val))
286		return -EINVAL;
287
288	val = (val & LP8788_STARTUP_TIME_M) >> LP8788_STARTUP_TIME_S;
289
290	return ENABLE_TIME_USEC * val;
291}
292
293static int lp8788_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
294{
295	struct lp8788_buck *buck = rdev_get_drvdata(rdev);
296	enum lp8788_buck_id id = rdev_get_id(rdev);
297	u8 mask, val;
298
299	mask = BUCK_FPWM_MASK(id);
300	switch (mode) {
301	case REGULATOR_MODE_FAST:
302		val = LP8788_FORCE_PWM << BUCK_FPWM_SHIFT(id);
303		break;
304	case REGULATOR_MODE_NORMAL:
305		val = LP8788_AUTO_PWM << BUCK_FPWM_SHIFT(id);
306		break;
307	default:
308		return -EINVAL;
309	}
310
311	return lp8788_update_bits(buck->lp, LP8788_BUCK_PWM, mask, val);
312}
313
314static unsigned int lp8788_buck_get_mode(struct regulator_dev *rdev)
315{
316	struct lp8788_buck *buck = rdev_get_drvdata(rdev);
317	enum lp8788_buck_id id = rdev_get_id(rdev);
318	u8 val;
319	int ret;
320
321	ret = lp8788_read_byte(buck->lp, LP8788_BUCK_PWM, &val);
322	if (ret)
323		return ret;
324
325	return val & BUCK_FPWM_MASK(id) ?
326				REGULATOR_MODE_FAST : REGULATOR_MODE_NORMAL;
327}
328
329static const struct regulator_ops lp8788_buck12_ops = {
330	.list_voltage = regulator_list_voltage_linear_range,
331	.map_voltage = regulator_map_voltage_linear_range,
332	.set_voltage_sel = lp8788_buck12_set_voltage_sel,
333	.get_voltage_sel = lp8788_buck12_get_voltage_sel,
334	.enable = regulator_enable_regmap,
335	.disable = regulator_disable_regmap,
336	.is_enabled = regulator_is_enabled_regmap,
337	.enable_time = lp8788_buck_enable_time,
338	.set_mode = lp8788_buck_set_mode,
339	.get_mode = lp8788_buck_get_mode,
340};
341
342static const struct regulator_ops lp8788_buck34_ops = {
343	.list_voltage = regulator_list_voltage_linear_range,
344	.map_voltage = regulator_map_voltage_linear_range,
345	.set_voltage_sel = regulator_set_voltage_sel_regmap,
346	.get_voltage_sel = regulator_get_voltage_sel_regmap,
347	.enable = regulator_enable_regmap,
348	.disable = regulator_disable_regmap,
349	.is_enabled = regulator_is_enabled_regmap,
350	.enable_time = lp8788_buck_enable_time,
351	.set_mode = lp8788_buck_set_mode,
352	.get_mode = lp8788_buck_get_mode,
353};
354
355static const struct regulator_desc lp8788_buck_desc[] = {
356	{
357		.name = "buck1",
358		.id = BUCK1,
359		.ops = &lp8788_buck12_ops,
360		.n_voltages = 26,
361		.linear_ranges = buck_volt_ranges,
362		.n_linear_ranges = ARRAY_SIZE(buck_volt_ranges),
363		.type = REGULATOR_VOLTAGE,
364		.owner = THIS_MODULE,
365		.enable_reg = LP8788_EN_BUCK,
366		.enable_mask = LP8788_EN_BUCK1_M,
367	},
368	{
369		.name = "buck2",
370		.id = BUCK2,
371		.ops = &lp8788_buck12_ops,
372		.n_voltages = 26,
373		.linear_ranges = buck_volt_ranges,
374		.n_linear_ranges = ARRAY_SIZE(buck_volt_ranges),
375		.type = REGULATOR_VOLTAGE,
376		.owner = THIS_MODULE,
377		.enable_reg = LP8788_EN_BUCK,
378		.enable_mask = LP8788_EN_BUCK2_M,
379	},
380	{
381		.name = "buck3",
382		.id = BUCK3,
383		.ops = &lp8788_buck34_ops,
384		.n_voltages = 26,
385		.linear_ranges = buck_volt_ranges,
386		.n_linear_ranges = ARRAY_SIZE(buck_volt_ranges),
387		.type = REGULATOR_VOLTAGE,
388		.owner = THIS_MODULE,
389		.vsel_reg = LP8788_BUCK3_VOUT,
390		.vsel_mask = LP8788_VOUT_M,
391		.enable_reg = LP8788_EN_BUCK,
392		.enable_mask = LP8788_EN_BUCK3_M,
393	},
394	{
395		.name = "buck4",
396		.id = BUCK4,
397		.ops = &lp8788_buck34_ops,
398		.n_voltages = 26,
399		.linear_ranges = buck_volt_ranges,
400		.n_linear_ranges = ARRAY_SIZE(buck_volt_ranges),
401		.type = REGULATOR_VOLTAGE,
402		.owner = THIS_MODULE,
403		.vsel_reg = LP8788_BUCK4_VOUT,
404		.vsel_mask = LP8788_VOUT_M,
405		.enable_reg = LP8788_EN_BUCK,
406		.enable_mask = LP8788_EN_BUCK4_M,
407	},
408};
409
410static int lp8788_dvs_gpio_request(struct platform_device *pdev,
411				struct lp8788_buck *buck,
412				enum lp8788_buck_id id)
413{
414	struct lp8788_platform_data *pdata = buck->lp->pdata;
415	struct device *dev = &pdev->dev;
416
417	switch (id) {
418	case BUCK1:
419		buck->gpio1 = devm_gpiod_get(dev, "dvs", GPIOD_OUT_LOW);
420		if (IS_ERR(buck->gpio1))
421			return PTR_ERR(buck->gpio1);
422		gpiod_set_consumer_name(buck->gpio1, "LP8788_B1_DVS");
423
424		buck->dvs = pdata->buck1_dvs;
425		break;
426	case BUCK2:
427		buck->gpio1 = devm_gpiod_get_index(dev, "dvs", 0, GPIOD_OUT_LOW);
428		if (IS_ERR(buck->gpio1))
429			return PTR_ERR(buck->gpio1);
430		gpiod_set_consumer_name(buck->gpio1, "LP8788_B2_DVS1");
431
432		buck->gpio2 = devm_gpiod_get_index(dev, "dvs", 1, GPIOD_OUT_LOW);
433		if (IS_ERR(buck->gpio2))
434			return PTR_ERR(buck->gpio2);
435		gpiod_set_consumer_name(buck->gpio2, "LP8788_B2_DVS2");
436
437		buck->dvs = pdata->buck2_dvs;
438		break;
439	default:
440		break;
441	}
442
443	return 0;
444}
445
446static int lp8788_init_dvs(struct platform_device *pdev,
447			struct lp8788_buck *buck, enum lp8788_buck_id id)
448{
449	struct lp8788_platform_data *pdata = buck->lp->pdata;
450	u8 mask[] = { LP8788_BUCK1_DVS_SEL_M, LP8788_BUCK2_DVS_SEL_M };
451	u8 val[]  = { LP8788_BUCK1_DVS_PIN, LP8788_BUCK2_DVS_PIN };
452	u8 default_dvs_mode[] = { LP8788_BUCK1_DVS_I2C, LP8788_BUCK2_DVS_I2C };
453
454	/* no dvs for buck3, 4 */
455	if (id > BUCK2)
456		return 0;
457
458	/* no dvs platform data, then dvs will be selected by I2C registers */
459	if (!pdata)
460		goto set_default_dvs_mode;
461
462	if ((id == BUCK1 && !pdata->buck1_dvs) ||
463		(id == BUCK2 && !pdata->buck2_dvs))
464		goto set_default_dvs_mode;
465
466	if (lp8788_dvs_gpio_request(pdev, buck, id))
467		goto set_default_dvs_mode;
468
469	return lp8788_update_bits(buck->lp, LP8788_BUCK_DVS_SEL, mask[id],
470				val[id]);
471
472set_default_dvs_mode:
473	return lp8788_update_bits(buck->lp, LP8788_BUCK_DVS_SEL, mask[id],
474				  default_dvs_mode[id]);
475}
476
477static int lp8788_buck_probe(struct platform_device *pdev)
478{
479	struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
480	int id = pdev->id;
481	struct lp8788_buck *buck;
482	struct regulator_config cfg = { };
483	struct regulator_dev *rdev;
484	int ret;
485
486	if (id >= LP8788_NUM_BUCKS)
487		return -EINVAL;
488
489	buck = devm_kzalloc(&pdev->dev, sizeof(struct lp8788_buck), GFP_KERNEL);
490	if (!buck)
491		return -ENOMEM;
492
493	buck->lp = lp;
494
495	ret = lp8788_init_dvs(pdev, buck, id);
496	if (ret)
497		return ret;
498
499	cfg.dev = pdev->dev.parent;
500	cfg.init_data = lp->pdata ? lp->pdata->buck_data[id] : NULL;
501	cfg.driver_data = buck;
502	cfg.regmap = lp->regmap;
503
504	rdev = devm_regulator_register(&pdev->dev, &lp8788_buck_desc[id], &cfg);
505	if (IS_ERR(rdev)) {
506		ret = PTR_ERR(rdev);
507		dev_err(&pdev->dev, "BUCK%d regulator register err = %d\n",
508				id + 1, ret);
509		return ret;
510	}
511
512	buck->regulator = rdev;
513	platform_set_drvdata(pdev, buck);
514
515	return 0;
516}
517
518static struct platform_driver lp8788_buck_driver = {
519	.probe = lp8788_buck_probe,
520	.driver = {
521		.name = LP8788_DEV_BUCK,
522		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
523	},
524};
525
526static int __init lp8788_buck_init(void)
527{
528	return platform_driver_register(&lp8788_buck_driver);
529}
530subsys_initcall(lp8788_buck_init);
531
532static void __exit lp8788_buck_exit(void)
533{
534	platform_driver_unregister(&lp8788_buck_driver);
535}
536module_exit(lp8788_buck_exit);
537
538MODULE_DESCRIPTION("TI LP8788 BUCK Driver");
539MODULE_AUTHOR("Milo Kim");
540MODULE_LICENSE("GPL");
541MODULE_ALIAS("platform:lp8788-buck");
542