1// SPDX-License-Identifier: GPL-2.0
2//
3// Linear Technology LTC3589,LTC3589-1 regulator support
4//
5// Copyright (c) 2014 Philipp Zabel <p.zabel@pengutronix.de>, Pengutronix
6
7#include <linux/i2c.h>
8#include <linux/init.h>
9#include <linux/interrupt.h>
10#include <linux/module.h>
11#include <linux/kernel.h>
12#include <linux/of.h>
13#include <linux/regmap.h>
14#include <linux/regulator/driver.h>
15#include <linux/regulator/of_regulator.h>
16
17#define DRIVER_NAME		"ltc3589"
18
19#define LTC3589_IRQSTAT		0x02
20#define LTC3589_SCR1		0x07
21#define LTC3589_OVEN		0x10
22#define LTC3589_SCR2		0x12
23#define LTC3589_PGSTAT		0x13
24#define LTC3589_VCCR		0x20
25#define LTC3589_CLIRQ		0x21
26#define LTC3589_B1DTV1		0x23
27#define LTC3589_B1DTV2		0x24
28#define LTC3589_VRRCR		0x25
29#define LTC3589_B2DTV1		0x26
30#define LTC3589_B2DTV2		0x27
31#define LTC3589_B3DTV1		0x29
32#define LTC3589_B3DTV2		0x2a
33#define LTC3589_L2DTV1		0x32
34#define LTC3589_L2DTV2		0x33
35
36#define LTC3589_IRQSTAT_PGOOD_TIMEOUT	BIT(3)
37#define LTC3589_IRQSTAT_UNDERVOLT_WARN	BIT(4)
38#define LTC3589_IRQSTAT_UNDERVOLT_FAULT	BIT(5)
39#define LTC3589_IRQSTAT_THERMAL_WARN	BIT(6)
40#define LTC3589_IRQSTAT_THERMAL_FAULT	BIT(7)
41
42#define LTC3589_OVEN_SW1		BIT(0)
43#define LTC3589_OVEN_SW2		BIT(1)
44#define LTC3589_OVEN_SW3		BIT(2)
45#define LTC3589_OVEN_BB_OUT		BIT(3)
46#define LTC3589_OVEN_LDO2		BIT(4)
47#define LTC3589_OVEN_LDO3		BIT(5)
48#define LTC3589_OVEN_LDO4		BIT(6)
49#define LTC3589_OVEN_SW_CTRL		BIT(7)
50
51#define LTC3589_VCCR_SW1_GO		BIT(0)
52#define LTC3589_VCCR_SW2_GO		BIT(2)
53#define LTC3589_VCCR_SW3_GO		BIT(4)
54#define LTC3589_VCCR_LDO2_GO		BIT(6)
55
56#define LTC3589_VRRCR_SW1_RAMP_MASK	GENMASK(1, 0)
57#define LTC3589_VRRCR_SW2_RAMP_MASK	GENMASK(3, 2)
58#define LTC3589_VRRCR_SW3_RAMP_MASK	GENMASK(5, 4)
59#define LTC3589_VRRCR_LDO2_RAMP_MASK	GENMASK(7, 6)
60
61enum ltc3589_variant {
62	LTC3589,
63	LTC3589_1,
64	LTC3589_2,
65};
66
67enum ltc3589_reg {
68	LTC3589_SW1,
69	LTC3589_SW2,
70	LTC3589_SW3,
71	LTC3589_BB_OUT,
72	LTC3589_LDO1,
73	LTC3589_LDO2,
74	LTC3589_LDO3,
75	LTC3589_LDO4,
76	LTC3589_NUM_REGULATORS,
77};
78
79struct ltc3589 {
80	struct regmap *regmap;
81	struct device *dev;
82	enum ltc3589_variant variant;
83	struct regulator_desc regulator_descs[LTC3589_NUM_REGULATORS];
84	struct regulator_dev *regulators[LTC3589_NUM_REGULATORS];
85};
86
87static const int ltc3589_ldo4[] = {
88	2800000, 2500000, 1800000, 3300000,
89};
90
91static const int ltc3589_12_ldo4[] = {
92	1200000, 1800000, 2500000, 3200000,
93};
94
95static const unsigned int ltc3589_ramp_table[] = {
96	880, 1750, 3500, 7000
97};
98
99static int ltc3589_set_suspend_voltage(struct regulator_dev *rdev, int uV)
100{
101	struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
102	int sel;
103
104	sel = regulator_map_voltage_linear(rdev, uV, uV);
105	if (sel < 0)
106		return sel;
107
108	/* DTV2 register follows right after the corresponding DTV1 register */
109	return regmap_update_bits(ltc3589->regmap, rdev->desc->vsel_reg + 1,
110				  rdev->desc->vsel_mask, sel);
111}
112
113static int ltc3589_set_suspend_mode(struct regulator_dev *rdev,
114				    unsigned int mode)
115{
116	struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
117	int mask, bit = 0;
118
119	/* VCCR reference selects are right next to the VCCR go bits */
120	mask = rdev->desc->apply_bit << 1;
121
122	if (mode == REGULATOR_MODE_STANDBY)
123		bit = mask;	/* Select DTV2 */
124
125	mask |= rdev->desc->apply_bit;
126	bit |= rdev->desc->apply_bit;
127	return regmap_update_bits(ltc3589->regmap, LTC3589_VCCR, mask, bit);
128}
129
130/* SW1, SW2, SW3, LDO2 */
131static const struct regulator_ops ltc3589_linear_regulator_ops = {
132	.enable = regulator_enable_regmap,
133	.disable = regulator_disable_regmap,
134	.is_enabled = regulator_is_enabled_regmap,
135	.list_voltage = regulator_list_voltage_linear,
136	.set_voltage_sel = regulator_set_voltage_sel_regmap,
137	.get_voltage_sel = regulator_get_voltage_sel_regmap,
138	.set_ramp_delay = regulator_set_ramp_delay_regmap,
139	.set_voltage_time_sel = regulator_set_voltage_time_sel,
140	.set_suspend_voltage = ltc3589_set_suspend_voltage,
141	.set_suspend_mode = ltc3589_set_suspend_mode,
142};
143
144/* BB_OUT, LDO3 */
145static const struct regulator_ops ltc3589_fixed_regulator_ops = {
146	.enable = regulator_enable_regmap,
147	.disable = regulator_disable_regmap,
148	.is_enabled = regulator_is_enabled_regmap,
149};
150
151/* LDO1 */
152static const struct regulator_ops ltc3589_fixed_standby_regulator_ops = {
153};
154
155/* LDO4 */
156static const struct regulator_ops ltc3589_table_regulator_ops = {
157	.enable = regulator_enable_regmap,
158	.disable = regulator_disable_regmap,
159	.is_enabled = regulator_is_enabled_regmap,
160	.list_voltage = regulator_list_voltage_table,
161	.set_voltage_sel = regulator_set_voltage_sel_regmap,
162	.get_voltage_sel = regulator_get_voltage_sel_regmap,
163};
164
165static inline unsigned int ltc3589_scale(unsigned int uV, u32 r1, u32 r2)
166{
167	uint64_t tmp;
168
169	if (uV == 0)
170		return 0;
171
172	tmp = (uint64_t)uV * r1;
173	do_div(tmp, r2);
174	return uV + (unsigned int)tmp;
175}
176
177static int ltc3589_of_parse_cb(struct device_node *np,
178			       const struct regulator_desc *desc,
179			       struct regulator_config *config)
180{
181	struct ltc3589 *ltc3589 = config->driver_data;
182	struct regulator_desc *rdesc = &ltc3589->regulator_descs[desc->id];
183	u32 r[2];
184	int ret;
185
186	/* Parse feedback voltage dividers. LDO3 and LDO4 don't have them */
187	if (desc->id >= LTC3589_LDO3)
188		return 0;
189
190	ret = of_property_read_u32_array(np, "lltc,fb-voltage-divider", r, 2);
191	if (ret) {
192		dev_err(ltc3589->dev, "Failed to parse voltage divider: %d\n",
193			ret);
194		return ret;
195	}
196
197	if (!r[0] || !r[1])
198		return 0;
199
200	rdesc->min_uV = ltc3589_scale(desc->min_uV, r[0], r[1]);
201	rdesc->uV_step = ltc3589_scale(desc->uV_step, r[0], r[1]);
202	rdesc->fixed_uV = ltc3589_scale(desc->fixed_uV, r[0], r[1]);
203
204	return 0;
205}
206
207#define LTC3589_REG(_name, _of_name, _ops, en_bit, dtv1_reg, dtv_mask)	\
208	[LTC3589_ ## _name] = {						\
209		.name = #_name,						\
210		.of_match = of_match_ptr(#_of_name),			\
211		.regulators_node = of_match_ptr("regulators"),		\
212		.of_parse_cb = ltc3589_of_parse_cb,			\
213		.n_voltages = (dtv_mask) + 1,				\
214		.fixed_uV = (dtv_mask) ? 0 : 800000,			\
215		.ops = &ltc3589_ ## _ops ## _regulator_ops,		\
216		.type = REGULATOR_VOLTAGE,				\
217		.id = LTC3589_ ## _name,				\
218		.owner = THIS_MODULE,					\
219		.vsel_reg = (dtv1_reg),					\
220		.vsel_mask = (dtv_mask),				\
221		.enable_reg = (en_bit) ? LTC3589_OVEN : 0,		\
222		.enable_mask = (en_bit),				\
223	}
224
225#define LTC3589_LINEAR_REG(_name, _of_name, _dtv1)			\
226	[LTC3589_ ## _name] = {						\
227		.name = #_name,						\
228		.of_match = of_match_ptr(#_of_name),			\
229		.regulators_node = of_match_ptr("regulators"),		\
230		.of_parse_cb = ltc3589_of_parse_cb,			\
231		.n_voltages = 32,					\
232		.min_uV = 362500,					\
233		.uV_step = 12500,					\
234		.ramp_delay = 1750,					\
235		.ops = &ltc3589_linear_regulator_ops,			\
236		.type = REGULATOR_VOLTAGE,				\
237		.id = LTC3589_ ## _name,				\
238		.owner = THIS_MODULE,					\
239		.vsel_reg = LTC3589_ ## _dtv1,				\
240		.vsel_mask = 0x1f,					\
241		.apply_reg = LTC3589_VCCR,				\
242		.apply_bit = LTC3589_VCCR_ ## _name ## _GO,		\
243		.enable_reg = LTC3589_OVEN,				\
244		.enable_mask = (LTC3589_OVEN_ ## _name),		\
245		.ramp_reg = LTC3589_VRRCR,				\
246		.ramp_mask = LTC3589_VRRCR_ ## _name ## _RAMP_MASK,	\
247		.ramp_delay_table = ltc3589_ramp_table,			\
248		.n_ramp_values = ARRAY_SIZE(ltc3589_ramp_table),	\
249	}
250
251
252#define LTC3589_FIXED_REG(_name, _of_name)				\
253	LTC3589_REG(_name, _of_name, fixed, LTC3589_OVEN_ ## _name, 0, 0)
254
255static const struct regulator_desc ltc3589_regulators[] = {
256	LTC3589_LINEAR_REG(SW1, sw1, B1DTV1),
257	LTC3589_LINEAR_REG(SW2, sw2, B2DTV1),
258	LTC3589_LINEAR_REG(SW3, sw3, B3DTV1),
259	LTC3589_FIXED_REG(BB_OUT, bb-out),
260	LTC3589_REG(LDO1, ldo1, fixed_standby, 0, 0, 0),
261	LTC3589_LINEAR_REG(LDO2, ldo2, L2DTV1),
262	LTC3589_FIXED_REG(LDO3, ldo3),
263	LTC3589_REG(LDO4, ldo4, table, LTC3589_OVEN_LDO4, LTC3589_L2DTV2, 0x60),
264};
265
266static bool ltc3589_writeable_reg(struct device *dev, unsigned int reg)
267{
268	switch (reg) {
269	case LTC3589_IRQSTAT:
270	case LTC3589_SCR1:
271	case LTC3589_OVEN:
272	case LTC3589_SCR2:
273	case LTC3589_VCCR:
274	case LTC3589_CLIRQ:
275	case LTC3589_B1DTV1:
276	case LTC3589_B1DTV2:
277	case LTC3589_VRRCR:
278	case LTC3589_B2DTV1:
279	case LTC3589_B2DTV2:
280	case LTC3589_B3DTV1:
281	case LTC3589_B3DTV2:
282	case LTC3589_L2DTV1:
283	case LTC3589_L2DTV2:
284		return true;
285	}
286	return false;
287}
288
289static bool ltc3589_readable_reg(struct device *dev, unsigned int reg)
290{
291	switch (reg) {
292	case LTC3589_IRQSTAT:
293	case LTC3589_SCR1:
294	case LTC3589_OVEN:
295	case LTC3589_SCR2:
296	case LTC3589_PGSTAT:
297	case LTC3589_VCCR:
298	case LTC3589_B1DTV1:
299	case LTC3589_B1DTV2:
300	case LTC3589_VRRCR:
301	case LTC3589_B2DTV1:
302	case LTC3589_B2DTV2:
303	case LTC3589_B3DTV1:
304	case LTC3589_B3DTV2:
305	case LTC3589_L2DTV1:
306	case LTC3589_L2DTV2:
307		return true;
308	}
309	return false;
310}
311
312static bool ltc3589_volatile_reg(struct device *dev, unsigned int reg)
313{
314	switch (reg) {
315	case LTC3589_IRQSTAT:
316	case LTC3589_PGSTAT:
317	case LTC3589_VCCR:
318		return true;
319	}
320	return false;
321}
322
323static const struct reg_default ltc3589_reg_defaults[] = {
324	{ LTC3589_SCR1,   0x00 },
325	{ LTC3589_OVEN,   0x00 },
326	{ LTC3589_SCR2,   0x00 },
327	{ LTC3589_VCCR,   0x00 },
328	{ LTC3589_B1DTV1, 0x19 },
329	{ LTC3589_B1DTV2, 0x19 },
330	{ LTC3589_VRRCR,  0xff },
331	{ LTC3589_B2DTV1, 0x19 },
332	{ LTC3589_B2DTV2, 0x19 },
333	{ LTC3589_B3DTV1, 0x19 },
334	{ LTC3589_B3DTV2, 0x19 },
335	{ LTC3589_L2DTV1, 0x19 },
336	{ LTC3589_L2DTV2, 0x19 },
337};
338
339static const struct regmap_config ltc3589_regmap_config = {
340	.reg_bits = 8,
341	.val_bits = 8,
342	.writeable_reg = ltc3589_writeable_reg,
343	.readable_reg = ltc3589_readable_reg,
344	.volatile_reg = ltc3589_volatile_reg,
345	.max_register = LTC3589_L2DTV2,
346	.reg_defaults = ltc3589_reg_defaults,
347	.num_reg_defaults = ARRAY_SIZE(ltc3589_reg_defaults),
348	.use_single_read = true,
349	.use_single_write = true,
350	.cache_type = REGCACHE_MAPLE,
351};
352
353static irqreturn_t ltc3589_isr(int irq, void *dev_id)
354{
355	struct ltc3589 *ltc3589 = dev_id;
356	unsigned int i, irqstat, event;
357
358	regmap_read(ltc3589->regmap, LTC3589_IRQSTAT, &irqstat);
359
360	if (irqstat & LTC3589_IRQSTAT_THERMAL_WARN) {
361		event = REGULATOR_EVENT_OVER_TEMP;
362		for (i = 0; i < LTC3589_NUM_REGULATORS; i++)
363			regulator_notifier_call_chain(ltc3589->regulators[i],
364						      event, NULL);
365	}
366
367	if (irqstat & LTC3589_IRQSTAT_UNDERVOLT_WARN) {
368		event = REGULATOR_EVENT_UNDER_VOLTAGE;
369		for (i = 0; i < LTC3589_NUM_REGULATORS; i++)
370			regulator_notifier_call_chain(ltc3589->regulators[i],
371						      event, NULL);
372	}
373
374	/* Clear warning condition */
375	regmap_write(ltc3589->regmap, LTC3589_CLIRQ, 0);
376
377	return IRQ_HANDLED;
378}
379
380static int ltc3589_probe(struct i2c_client *client)
381{
382	const struct i2c_device_id *id = i2c_client_get_device_id(client);
383	struct device *dev = &client->dev;
384	struct regulator_desc *descs;
385	struct ltc3589 *ltc3589;
386	int i, ret;
387
388	ltc3589 = devm_kzalloc(dev, sizeof(*ltc3589), GFP_KERNEL);
389	if (!ltc3589)
390		return -ENOMEM;
391
392	i2c_set_clientdata(client, ltc3589);
393	if (client->dev.of_node)
394		ltc3589->variant = (uintptr_t)of_device_get_match_data(&client->dev);
395	else
396		ltc3589->variant = id->driver_data;
397	ltc3589->dev = dev;
398
399	descs = ltc3589->regulator_descs;
400	memcpy(descs, ltc3589_regulators, sizeof(ltc3589_regulators));
401	if (ltc3589->variant == LTC3589) {
402		descs[LTC3589_LDO3].fixed_uV = 1800000;
403		descs[LTC3589_LDO4].volt_table = ltc3589_ldo4;
404	} else {
405		descs[LTC3589_LDO3].fixed_uV = 2800000;
406		descs[LTC3589_LDO4].volt_table = ltc3589_12_ldo4;
407	}
408
409	ltc3589->regmap = devm_regmap_init_i2c(client, &ltc3589_regmap_config);
410	if (IS_ERR(ltc3589->regmap)) {
411		ret = PTR_ERR(ltc3589->regmap);
412		dev_err(dev, "failed to initialize regmap: %d\n", ret);
413		return ret;
414	}
415
416	for (i = 0; i < LTC3589_NUM_REGULATORS; i++) {
417		struct regulator_desc *desc = &ltc3589->regulator_descs[i];
418		struct regulator_config config = { };
419
420		config.dev = dev;
421		config.driver_data = ltc3589;
422
423		ltc3589->regulators[i] = devm_regulator_register(dev, desc,
424								 &config);
425		if (IS_ERR(ltc3589->regulators[i])) {
426			ret = PTR_ERR(ltc3589->regulators[i]);
427			dev_err(dev, "failed to register regulator %s: %d\n",
428				desc->name, ret);
429			return ret;
430		}
431	}
432
433	if (client->irq) {
434		ret = devm_request_threaded_irq(dev, client->irq, NULL,
435						ltc3589_isr,
436						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
437						client->name, ltc3589);
438		if (ret) {
439			dev_err(dev, "Failed to request IRQ: %d\n", ret);
440			return ret;
441		}
442	}
443
444	return 0;
445}
446
447static const struct i2c_device_id ltc3589_i2c_id[] = {
448	{ "ltc3589",   LTC3589   },
449	{ "ltc3589-1", LTC3589_1 },
450	{ "ltc3589-2", LTC3589_2 },
451	{ }
452};
453MODULE_DEVICE_TABLE(i2c, ltc3589_i2c_id);
454
455static const struct of_device_id __maybe_unused ltc3589_of_match[] = {
456	{
457		.compatible = "lltc,ltc3589",
458		.data = (void *)LTC3589,
459	},
460	{
461		.compatible = "lltc,ltc3589-1",
462		.data = (void *)LTC3589_1,
463	},
464	{
465		.compatible = "lltc,ltc3589-2",
466		.data = (void *)LTC3589_2,
467	},
468	{ },
469};
470MODULE_DEVICE_TABLE(of, ltc3589_of_match);
471
472static struct i2c_driver ltc3589_driver = {
473	.driver = {
474		.name = DRIVER_NAME,
475		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
476		.of_match_table = of_match_ptr(ltc3589_of_match),
477	},
478	.probe = ltc3589_probe,
479	.id_table = ltc3589_i2c_id,
480};
481module_i2c_driver(ltc3589_driver);
482
483MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");
484MODULE_DESCRIPTION("Regulator driver for Linear Technology LTC3589(-1,2)");
485MODULE_LICENSE("GPL v2");
486