xref: /openbmc/linux/drivers/regulator/ltc3589.c (revision 7559e757) 
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/of_device.h>
14 #include <linux/regmap.h>
15 #include <linux/regulator/driver.h>
16 #include <linux/regulator/of_regulator.h>
17 
18 #define DRIVER_NAME		"ltc3589"
19 
20 #define LTC3589_IRQSTAT		0x02
21 #define LTC3589_SCR1		0x07
22 #define LTC3589_OVEN		0x10
23 #define LTC3589_SCR2		0x12
24 #define LTC3589_PGSTAT		0x13
25 #define LTC3589_VCCR		0x20
26 #define LTC3589_CLIRQ		0x21
27 #define LTC3589_B1DTV1		0x23
28 #define LTC3589_B1DTV2		0x24
29 #define LTC3589_VRRCR		0x25
30 #define LTC3589_B2DTV1		0x26
31 #define LTC3589_B2DTV2		0x27
32 #define LTC3589_B3DTV1		0x29
33 #define LTC3589_B3DTV2		0x2a
34 #define LTC3589_L2DTV1		0x32
35 #define LTC3589_L2DTV2		0x33
36 
37 #define LTC3589_IRQSTAT_PGOOD_TIMEOUT	BIT(3)
38 #define LTC3589_IRQSTAT_UNDERVOLT_WARN	BIT(4)
39 #define LTC3589_IRQSTAT_UNDERVOLT_FAULT	BIT(5)
40 #define LTC3589_IRQSTAT_THERMAL_WARN	BIT(6)
41 #define LTC3589_IRQSTAT_THERMAL_FAULT	BIT(7)
42 
43 #define LTC3589_OVEN_SW1		BIT(0)
44 #define LTC3589_OVEN_SW2		BIT(1)
45 #define LTC3589_OVEN_SW3		BIT(2)
46 #define LTC3589_OVEN_BB_OUT		BIT(3)
47 #define LTC3589_OVEN_LDO2		BIT(4)
48 #define LTC3589_OVEN_LDO3		BIT(5)
49 #define LTC3589_OVEN_LDO4		BIT(6)
50 #define LTC3589_OVEN_SW_CTRL		BIT(7)
51 
52 #define LTC3589_VCCR_SW1_GO		BIT(0)
53 #define LTC3589_VCCR_SW2_GO		BIT(2)
54 #define LTC3589_VCCR_SW3_GO		BIT(4)
55 #define LTC3589_VCCR_LDO2_GO		BIT(6)
56 
57 #define LTC3589_VRRCR_SW1_RAMP_MASK	GENMASK(1, 0)
58 #define LTC3589_VRRCR_SW2_RAMP_MASK	GENMASK(3, 2)
59 #define LTC3589_VRRCR_SW3_RAMP_MASK	GENMASK(5, 4)
60 #define LTC3589_VRRCR_LDO2_RAMP_MASK	GENMASK(7, 6)
61 
62 enum ltc3589_variant {
63 	LTC3589,
64 	LTC3589_1,
65 	LTC3589_2,
66 };
67 
68 enum ltc3589_reg {
69 	LTC3589_SW1,
70 	LTC3589_SW2,
71 	LTC3589_SW3,
72 	LTC3589_BB_OUT,
73 	LTC3589_LDO1,
74 	LTC3589_LDO2,
75 	LTC3589_LDO3,
76 	LTC3589_LDO4,
77 	LTC3589_NUM_REGULATORS,
78 };
79 
80 struct ltc3589 {
81 	struct regmap *regmap;
82 	struct device *dev;
83 	enum ltc3589_variant variant;
84 	struct regulator_desc regulator_descs[LTC3589_NUM_REGULATORS];
85 	struct regulator_dev *regulators[LTC3589_NUM_REGULATORS];
86 };
87 
88 static const int ltc3589_ldo4[] = {
89 	2800000, 2500000, 1800000, 3300000,
90 };
91 
92 static const int ltc3589_12_ldo4[] = {
93 	1200000, 1800000, 2500000, 3200000,
94 };
95 
96 static const unsigned int ltc3589_ramp_table[] = {
97 	880, 1750, 3500, 7000
98 };
99 
100 static int ltc3589_set_suspend_voltage(struct regulator_dev *rdev, int uV)
101 {
102 	struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
103 	int sel;
104 
105 	sel = regulator_map_voltage_linear(rdev, uV, uV);
106 	if (sel < 0)
107 		return sel;
108 
109 	/* DTV2 register follows right after the corresponding DTV1 register */
110 	return regmap_update_bits(ltc3589->regmap, rdev->desc->vsel_reg + 1,
111 				  rdev->desc->vsel_mask, sel);
112 }
113 
114 static int ltc3589_set_suspend_mode(struct regulator_dev *rdev,
115 				    unsigned int mode)
116 {
117 	struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
118 	int mask, bit = 0;
119 
120 	/* VCCR reference selects are right next to the VCCR go bits */
121 	mask = rdev->desc->apply_bit << 1;
122 
123 	if (mode == REGULATOR_MODE_STANDBY)
124 		bit = mask;	/* Select DTV2 */
125 
126 	mask |= rdev->desc->apply_bit;
127 	bit |= rdev->desc->apply_bit;
128 	return regmap_update_bits(ltc3589->regmap, LTC3589_VCCR, mask, bit);
129 }
130 
131 /* SW1, SW2, SW3, LDO2 */
132 static const struct regulator_ops ltc3589_linear_regulator_ops = {
133 	.enable = regulator_enable_regmap,
134 	.disable = regulator_disable_regmap,
135 	.is_enabled = regulator_is_enabled_regmap,
136 	.list_voltage = regulator_list_voltage_linear,
137 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
138 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
139 	.set_ramp_delay = regulator_set_ramp_delay_regmap,
140 	.set_voltage_time_sel = regulator_set_voltage_time_sel,
141 	.set_suspend_voltage = ltc3589_set_suspend_voltage,
142 	.set_suspend_mode = ltc3589_set_suspend_mode,
143 };
144 
145 /* BB_OUT, LDO3 */
146 static const struct regulator_ops ltc3589_fixed_regulator_ops = {
147 	.enable = regulator_enable_regmap,
148 	.disable = regulator_disable_regmap,
149 	.is_enabled = regulator_is_enabled_regmap,
150 };
151 
152 /* LDO1 */
153 static const struct regulator_ops ltc3589_fixed_standby_regulator_ops = {
154 };
155 
156 /* LDO4 */
157 static const struct regulator_ops ltc3589_table_regulator_ops = {
158 	.enable = regulator_enable_regmap,
159 	.disable = regulator_disable_regmap,
160 	.is_enabled = regulator_is_enabled_regmap,
161 	.list_voltage = regulator_list_voltage_table,
162 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
163 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
164 };
165 
166 static inline unsigned int ltc3589_scale(unsigned int uV, u32 r1, u32 r2)
167 {
168 	uint64_t tmp;
169 
170 	if (uV == 0)
171 		return 0;
172 
173 	tmp = (uint64_t)uV * r1;
174 	do_div(tmp, r2);
175 	return uV + (unsigned int)tmp;
176 }
177 
178 static int ltc3589_of_parse_cb(struct device_node *np,
179 			       const struct regulator_desc *desc,
180 			       struct regulator_config *config)
181 {
182 	struct ltc3589 *ltc3589 = config->driver_data;
183 	struct regulator_desc *rdesc = &ltc3589->regulator_descs[desc->id];
184 	u32 r[2];
185 	int ret;
186 
187 	/* Parse feedback voltage dividers. LDO3 and LDO4 don't have them */
188 	if (desc->id >= LTC3589_LDO3)
189 		return 0;
190 
191 	ret = of_property_read_u32_array(np, "lltc,fb-voltage-divider", r, 2);
192 	if (ret) {
193 		dev_err(ltc3589->dev, "Failed to parse voltage divider: %d\n",
194 			ret);
195 		return ret;
196 	}
197 
198 	if (!r[0] || !r[1])
199 		return 0;
200 
201 	rdesc->min_uV = ltc3589_scale(desc->min_uV, r[0], r[1]);
202 	rdesc->uV_step = ltc3589_scale(desc->uV_step, r[0], r[1]);
203 	rdesc->fixed_uV = ltc3589_scale(desc->fixed_uV, r[0], r[1]);
204 
205 	return 0;
206 }
207 
208 #define LTC3589_REG(_name, _of_name, _ops, en_bit, dtv1_reg, dtv_mask)	\
209 	[LTC3589_ ## _name] = {						\
210 		.name = #_name,						\
211 		.of_match = of_match_ptr(#_of_name),			\
212 		.regulators_node = of_match_ptr("regulators"),		\
213 		.of_parse_cb = ltc3589_of_parse_cb,			\
214 		.n_voltages = (dtv_mask) + 1,				\
215 		.fixed_uV = (dtv_mask) ? 0 : 800000,			\
216 		.ops = &ltc3589_ ## _ops ## _regulator_ops,		\
217 		.type = REGULATOR_VOLTAGE,				\
218 		.id = LTC3589_ ## _name,				\
219 		.owner = THIS_MODULE,					\
220 		.vsel_reg = (dtv1_reg),					\
221 		.vsel_mask = (dtv_mask),				\
222 		.enable_reg = (en_bit) ? LTC3589_OVEN : 0,		\
223 		.enable_mask = (en_bit),				\
224 	}
225 
226 #define LTC3589_LINEAR_REG(_name, _of_name, _dtv1)			\
227 	[LTC3589_ ## _name] = {						\
228 		.name = #_name,						\
229 		.of_match = of_match_ptr(#_of_name),			\
230 		.regulators_node = of_match_ptr("regulators"),		\
231 		.of_parse_cb = ltc3589_of_parse_cb,			\
232 		.n_voltages = 32,					\
233 		.min_uV = 362500,					\
234 		.uV_step = 12500,					\
235 		.ramp_delay = 1750,					\
236 		.ops = &ltc3589_linear_regulator_ops,			\
237 		.type = REGULATOR_VOLTAGE,				\
238 		.id = LTC3589_ ## _name,				\
239 		.owner = THIS_MODULE,					\
240 		.vsel_reg = LTC3589_ ## _dtv1,				\
241 		.vsel_mask = 0x1f,					\
242 		.apply_reg = LTC3589_VCCR,				\
243 		.apply_bit = LTC3589_VCCR_ ## _name ## _GO,		\
244 		.enable_reg = LTC3589_OVEN,				\
245 		.enable_mask = (LTC3589_OVEN_ ## _name),		\
246 		.ramp_reg = LTC3589_VRRCR,				\
247 		.ramp_mask = LTC3589_VRRCR_ ## _name ## _RAMP_MASK,	\
248 		.ramp_delay_table = ltc3589_ramp_table,			\
249 		.n_ramp_values = ARRAY_SIZE(ltc3589_ramp_table),	\
250 	}
251 
252 
253 #define LTC3589_FIXED_REG(_name, _of_name)				\
254 	LTC3589_REG(_name, _of_name, fixed, LTC3589_OVEN_ ## _name, 0, 0)
255 
256 static const struct regulator_desc ltc3589_regulators[] = {
257 	LTC3589_LINEAR_REG(SW1, sw1, B1DTV1),
258 	LTC3589_LINEAR_REG(SW2, sw2, B2DTV1),
259 	LTC3589_LINEAR_REG(SW3, sw3, B3DTV1),
260 	LTC3589_FIXED_REG(BB_OUT, bb-out),
261 	LTC3589_REG(LDO1, ldo1, fixed_standby, 0, 0, 0),
262 	LTC3589_LINEAR_REG(LDO2, ldo2, L2DTV1),
263 	LTC3589_FIXED_REG(LDO3, ldo3),
264 	LTC3589_REG(LDO4, ldo4, table, LTC3589_OVEN_LDO4, LTC3589_L2DTV2, 0x60),
265 };
266 
267 static bool ltc3589_writeable_reg(struct device *dev, unsigned int reg)
268 {
269 	switch (reg) {
270 	case LTC3589_IRQSTAT:
271 	case LTC3589_SCR1:
272 	case LTC3589_OVEN:
273 	case LTC3589_SCR2:
274 	case LTC3589_VCCR:
275 	case LTC3589_CLIRQ:
276 	case LTC3589_B1DTV1:
277 	case LTC3589_B1DTV2:
278 	case LTC3589_VRRCR:
279 	case LTC3589_B2DTV1:
280 	case LTC3589_B2DTV2:
281 	case LTC3589_B3DTV1:
282 	case LTC3589_B3DTV2:
283 	case LTC3589_L2DTV1:
284 	case LTC3589_L2DTV2:
285 		return true;
286 	}
287 	return false;
288 }
289 
290 static bool ltc3589_readable_reg(struct device *dev, unsigned int reg)
291 {
292 	switch (reg) {
293 	case LTC3589_IRQSTAT:
294 	case LTC3589_SCR1:
295 	case LTC3589_OVEN:
296 	case LTC3589_SCR2:
297 	case LTC3589_PGSTAT:
298 	case LTC3589_VCCR:
299 	case LTC3589_B1DTV1:
300 	case LTC3589_B1DTV2:
301 	case LTC3589_VRRCR:
302 	case LTC3589_B2DTV1:
303 	case LTC3589_B2DTV2:
304 	case LTC3589_B3DTV1:
305 	case LTC3589_B3DTV2:
306 	case LTC3589_L2DTV1:
307 	case LTC3589_L2DTV2:
308 		return true;
309 	}
310 	return false;
311 }
312 
313 static bool ltc3589_volatile_reg(struct device *dev, unsigned int reg)
314 {
315 	switch (reg) {
316 	case LTC3589_IRQSTAT:
317 	case LTC3589_PGSTAT:
318 	case LTC3589_VCCR:
319 		return true;
320 	}
321 	return false;
322 }
323 
324 static const struct reg_default ltc3589_reg_defaults[] = {
325 	{ LTC3589_SCR1,   0x00 },
326 	{ LTC3589_OVEN,   0x00 },
327 	{ LTC3589_SCR2,   0x00 },
328 	{ LTC3589_VCCR,   0x00 },
329 	{ LTC3589_B1DTV1, 0x19 },
330 	{ LTC3589_B1DTV2, 0x19 },
331 	{ LTC3589_VRRCR,  0xff },
332 	{ LTC3589_B2DTV1, 0x19 },
333 	{ LTC3589_B2DTV2, 0x19 },
334 	{ LTC3589_B3DTV1, 0x19 },
335 	{ LTC3589_B3DTV2, 0x19 },
336 	{ LTC3589_L2DTV1, 0x19 },
337 	{ LTC3589_L2DTV2, 0x19 },
338 };
339 
340 static const struct regmap_config ltc3589_regmap_config = {
341 	.reg_bits = 8,
342 	.val_bits = 8,
343 	.writeable_reg = ltc3589_writeable_reg,
344 	.readable_reg = ltc3589_readable_reg,
345 	.volatile_reg = ltc3589_volatile_reg,
346 	.max_register = LTC3589_L2DTV2,
347 	.reg_defaults = ltc3589_reg_defaults,
348 	.num_reg_defaults = ARRAY_SIZE(ltc3589_reg_defaults),
349 	.use_single_read = true,
350 	.use_single_write = true,
351 	.cache_type = REGCACHE_MAPLE,
352 };
353 
354 static irqreturn_t ltc3589_isr(int irq, void *dev_id)
355 {
356 	struct ltc3589 *ltc3589 = dev_id;
357 	unsigned int i, irqstat, event;
358 
359 	regmap_read(ltc3589->regmap, LTC3589_IRQSTAT, &irqstat);
360 
361 	if (irqstat & LTC3589_IRQSTAT_THERMAL_WARN) {
362 		event = REGULATOR_EVENT_OVER_TEMP;
363 		for (i = 0; i < LTC3589_NUM_REGULATORS; i++)
364 			regulator_notifier_call_chain(ltc3589->regulators[i],
365 						      event, NULL);
366 	}
367 
368 	if (irqstat & LTC3589_IRQSTAT_UNDERVOLT_WARN) {
369 		event = REGULATOR_EVENT_UNDER_VOLTAGE;
370 		for (i = 0; i < LTC3589_NUM_REGULATORS; i++)
371 			regulator_notifier_call_chain(ltc3589->regulators[i],
372 						      event, NULL);
373 	}
374 
375 	/* Clear warning condition */
376 	regmap_write(ltc3589->regmap, LTC3589_CLIRQ, 0);
377 
378 	return IRQ_HANDLED;
379 }
380 
381 static int ltc3589_probe(struct i2c_client *client)
382 {
383 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
384 	struct device *dev = &client->dev;
385 	struct regulator_desc *descs;
386 	struct ltc3589 *ltc3589;
387 	int i, ret;
388 
389 	ltc3589 = devm_kzalloc(dev, sizeof(*ltc3589), GFP_KERNEL);
390 	if (!ltc3589)
391 		return -ENOMEM;
392 
393 	i2c_set_clientdata(client, ltc3589);
394 	if (client->dev.of_node)
395 		ltc3589->variant = (enum ltc3589_variant)
396 			of_device_get_match_data(&client->dev);
397 	else
398 		ltc3589->variant = id->driver_data;
399 	ltc3589->dev = dev;
400 
401 	descs = ltc3589->regulator_descs;
402 	memcpy(descs, ltc3589_regulators, sizeof(ltc3589_regulators));
403 	if (ltc3589->variant == LTC3589) {
404 		descs[LTC3589_LDO3].fixed_uV = 1800000;
405 		descs[LTC3589_LDO4].volt_table = ltc3589_ldo4;
406 	} else {
407 		descs[LTC3589_LDO3].fixed_uV = 2800000;
408 		descs[LTC3589_LDO4].volt_table = ltc3589_12_ldo4;
409 	}
410 
411 	ltc3589->regmap = devm_regmap_init_i2c(client, &ltc3589_regmap_config);
412 	if (IS_ERR(ltc3589->regmap)) {
413 		ret = PTR_ERR(ltc3589->regmap);
414 		dev_err(dev, "failed to initialize regmap: %d\n", ret);
415 		return ret;
416 	}
417 
418 	for (i = 0; i < LTC3589_NUM_REGULATORS; i++) {
419 		struct regulator_desc *desc = &ltc3589->regulator_descs[i];
420 		struct regulator_config config = { };
421 
422 		config.dev = dev;
423 		config.driver_data = ltc3589;
424 
425 		ltc3589->regulators[i] = devm_regulator_register(dev, desc,
426 								 &config);
427 		if (IS_ERR(ltc3589->regulators[i])) {
428 			ret = PTR_ERR(ltc3589->regulators[i]);
429 			dev_err(dev, "failed to register regulator %s: %d\n",
430 				desc->name, ret);
431 			return ret;
432 		}
433 	}
434 
435 	if (client->irq) {
436 		ret = devm_request_threaded_irq(dev, client->irq, NULL,
437 						ltc3589_isr,
438 						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
439 						client->name, ltc3589);
440 		if (ret) {
441 			dev_err(dev, "Failed to request IRQ: %d\n", ret);
442 			return ret;
443 		}
444 	}
445 
446 	return 0;
447 }
448 
449 static const struct i2c_device_id ltc3589_i2c_id[] = {
450 	{ "ltc3589",   LTC3589   },
451 	{ "ltc3589-1", LTC3589_1 },
452 	{ "ltc3589-2", LTC3589_2 },
453 	{ }
454 };
455 MODULE_DEVICE_TABLE(i2c, ltc3589_i2c_id);
456 
457 static const struct of_device_id __maybe_unused ltc3589_of_match[] = {
458 	{
459 		.compatible = "lltc,ltc3589",
460 		.data = (void *)LTC3589,
461 	},
462 	{
463 		.compatible = "lltc,ltc3589-1",
464 		.data = (void *)LTC3589_1,
465 	},
466 	{
467 		.compatible = "lltc,ltc3589-2",
468 		.data = (void *)LTC3589_2,
469 	},
470 	{ },
471 };
472 MODULE_DEVICE_TABLE(of, ltc3589_of_match);
473 
474 static struct i2c_driver ltc3589_driver = {
475 	.driver = {
476 		.name = DRIVER_NAME,
477 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
478 		.of_match_table = of_match_ptr(ltc3589_of_match),
479 	},
480 	.probe = ltc3589_probe,
481 	.id_table = ltc3589_i2c_id,
482 };
483 module_i2c_driver(ltc3589_driver);
484 
485 MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");
486 MODULE_DESCRIPTION("Regulator driver for Linear Technology LTC3589(-1,2)");
487 MODULE_LICENSE("GPL v2");
488