xref: /openbmc/linux/drivers/regulator/ltc3589.c (revision e2ad626f) 
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 
61 enum ltc3589_variant {
62 	LTC3589,
63 	LTC3589_1,
64 	LTC3589_2,
65 };
66 
67 enum 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 
79 struct 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 
87 static const int ltc3589_ldo4[] = {
88 	2800000, 2500000, 1800000, 3300000,
89 };
90 
91 static const int ltc3589_12_ldo4[] = {
92 	1200000, 1800000, 2500000, 3200000,
93 };
94 
95 static const unsigned int ltc3589_ramp_table[] = {
96 	880, 1750, 3500, 7000
97 };
98 
99 static 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 
113 static 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 */
131 static 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 */
145 static 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 */
152 static const struct regulator_ops ltc3589_fixed_standby_regulator_ops = {
153 };
154 
155 /* LDO4 */
156 static 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 
165 static 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 
177 static 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 
255 static 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 
266 static 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 
289 static 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 
312 static 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 
323 static 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 
339 static 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 
353 static 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 
380 static 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 
447 static const struct i2c_device_id ltc3589_i2c_id[] = {
448 	{ "ltc3589",   LTC3589   },
449 	{ "ltc3589-1", LTC3589_1 },
450 	{ "ltc3589-2", LTC3589_2 },
451 	{ }
452 };
453 MODULE_DEVICE_TABLE(i2c, ltc3589_i2c_id);
454 
455 static 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 };
470 MODULE_DEVICE_TABLE(of, ltc3589_of_match);
471 
472 static 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 };
481 module_i2c_driver(ltc3589_driver);
482 
483 MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");
484 MODULE_DESCRIPTION("Regulator driver for Linear Technology LTC3589(-1,2)");
485 MODULE_LICENSE("GPL v2");
486