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_reg {
62 	LTC3589_SW1,
63 	LTC3589_SW2,
64 	LTC3589_SW3,
65 	LTC3589_BB_OUT,
66 	LTC3589_LDO1,
67 	LTC3589_LDO2,
68 	LTC3589_LDO3,
69 	LTC3589_LDO4,
70 	LTC3589_NUM_REGULATORS,
71 };
72 
73 struct ltc3589_info {
74 	const unsigned int *volt_table;
75 	int fixed_uV;
76 };
77 
78 struct ltc3589 {
79 	struct regmap *regmap;
80 	struct device *dev;
81 	struct regulator_desc regulator_descs[LTC3589_NUM_REGULATORS];
82 	struct regulator_dev *regulators[LTC3589_NUM_REGULATORS];
83 };
84 
85 static const int ltc3589_ldo4[] = {
86 	2800000, 2500000, 1800000, 3300000,
87 };
88 
89 static const int ltc3589_12_ldo4[] = {
90 	1200000, 1800000, 2500000, 3200000,
91 };
92 
93 static const unsigned int ltc3589_ramp_table[] = {
94 	880, 1750, 3500, 7000
95 };
96 
ltc3589_set_suspend_voltage(struct regulator_dev * rdev,int uV)97 static int ltc3589_set_suspend_voltage(struct regulator_dev *rdev, int uV)
98 {
99 	struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
100 	int sel;
101 
102 	sel = regulator_map_voltage_linear(rdev, uV, uV);
103 	if (sel < 0)
104 		return sel;
105 
106 	/* DTV2 register follows right after the corresponding DTV1 register */
107 	return regmap_update_bits(ltc3589->regmap, rdev->desc->vsel_reg + 1,
108 				  rdev->desc->vsel_mask, sel);
109 }
110 
ltc3589_set_suspend_mode(struct regulator_dev * rdev,unsigned int mode)111 static int ltc3589_set_suspend_mode(struct regulator_dev *rdev,
112 				    unsigned int mode)
113 {
114 	struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
115 	int mask, bit = 0;
116 
117 	/* VCCR reference selects are right next to the VCCR go bits */
118 	mask = rdev->desc->apply_bit << 1;
119 
120 	if (mode == REGULATOR_MODE_STANDBY)
121 		bit = mask;	/* Select DTV2 */
122 
123 	mask |= rdev->desc->apply_bit;
124 	bit |= rdev->desc->apply_bit;
125 	return regmap_update_bits(ltc3589->regmap, LTC3589_VCCR, mask, bit);
126 }
127 
128 /* SW1, SW2, SW3, LDO2 */
129 static const struct regulator_ops ltc3589_linear_regulator_ops = {
130 	.enable = regulator_enable_regmap,
131 	.disable = regulator_disable_regmap,
132 	.is_enabled = regulator_is_enabled_regmap,
133 	.list_voltage = regulator_list_voltage_linear,
134 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
135 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
136 	.set_ramp_delay = regulator_set_ramp_delay_regmap,
137 	.set_voltage_time_sel = regulator_set_voltage_time_sel,
138 	.set_suspend_voltage = ltc3589_set_suspend_voltage,
139 	.set_suspend_mode = ltc3589_set_suspend_mode,
140 };
141 
142 /* BB_OUT, LDO3 */
143 static const struct regulator_ops ltc3589_fixed_regulator_ops = {
144 	.enable = regulator_enable_regmap,
145 	.disable = regulator_disable_regmap,
146 	.is_enabled = regulator_is_enabled_regmap,
147 };
148 
149 /* LDO1 */
150 static const struct regulator_ops ltc3589_fixed_standby_regulator_ops = {
151 };
152 
153 /* LDO4 */
154 static const struct regulator_ops ltc3589_table_regulator_ops = {
155 	.enable = regulator_enable_regmap,
156 	.disable = regulator_disable_regmap,
157 	.is_enabled = regulator_is_enabled_regmap,
158 	.list_voltage = regulator_list_voltage_table,
159 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
160 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
161 };
162 
ltc3589_scale(unsigned int uV,u32 r1,u32 r2)163 static inline unsigned int ltc3589_scale(unsigned int uV, u32 r1, u32 r2)
164 {
165 	uint64_t tmp;
166 
167 	if (uV == 0)
168 		return 0;
169 
170 	tmp = (uint64_t)uV * r1;
171 	do_div(tmp, r2);
172 	return uV + (unsigned int)tmp;
173 }
174 
ltc3589_of_parse_cb(struct device_node * np,const struct regulator_desc * desc,struct regulator_config * config)175 static int ltc3589_of_parse_cb(struct device_node *np,
176 			       const struct regulator_desc *desc,
177 			       struct regulator_config *config)
178 {
179 	struct ltc3589 *ltc3589 = config->driver_data;
180 	struct regulator_desc *rdesc = &ltc3589->regulator_descs[desc->id];
181 	u32 r[2];
182 	int ret;
183 
184 	/* Parse feedback voltage dividers. LDO3 and LDO4 don't have them */
185 	if (desc->id >= LTC3589_LDO3)
186 		return 0;
187 
188 	ret = of_property_read_u32_array(np, "lltc,fb-voltage-divider", r, 2);
189 	if (ret) {
190 		dev_err(ltc3589->dev, "Failed to parse voltage divider: %d\n",
191 			ret);
192 		return ret;
193 	}
194 
195 	if (!r[0] || !r[1])
196 		return 0;
197 
198 	rdesc->min_uV = ltc3589_scale(desc->min_uV, r[0], r[1]);
199 	rdesc->uV_step = ltc3589_scale(desc->uV_step, r[0], r[1]);
200 	rdesc->fixed_uV = ltc3589_scale(desc->fixed_uV, r[0], r[1]);
201 
202 	return 0;
203 }
204 
205 #define LTC3589_REG(_name, _of_name, _ops, en_bit, dtv1_reg, dtv_mask)	\
206 	[LTC3589_ ## _name] = {						\
207 		.name = #_name,						\
208 		.of_match = of_match_ptr(#_of_name),			\
209 		.regulators_node = of_match_ptr("regulators"),		\
210 		.of_parse_cb = ltc3589_of_parse_cb,			\
211 		.n_voltages = (dtv_mask) + 1,				\
212 		.fixed_uV = (dtv_mask) ? 0 : 800000,			\
213 		.ops = &ltc3589_ ## _ops ## _regulator_ops,		\
214 		.type = REGULATOR_VOLTAGE,				\
215 		.id = LTC3589_ ## _name,				\
216 		.owner = THIS_MODULE,					\
217 		.vsel_reg = (dtv1_reg),					\
218 		.vsel_mask = (dtv_mask),				\
219 		.enable_reg = (en_bit) ? LTC3589_OVEN : 0,		\
220 		.enable_mask = (en_bit),				\
221 	}
222 
223 #define LTC3589_LINEAR_REG(_name, _of_name, _dtv1)			\
224 	[LTC3589_ ## _name] = {						\
225 		.name = #_name,						\
226 		.of_match = of_match_ptr(#_of_name),			\
227 		.regulators_node = of_match_ptr("regulators"),		\
228 		.of_parse_cb = ltc3589_of_parse_cb,			\
229 		.n_voltages = 32,					\
230 		.min_uV = 362500,					\
231 		.uV_step = 12500,					\
232 		.ramp_delay = 1750,					\
233 		.ops = &ltc3589_linear_regulator_ops,			\
234 		.type = REGULATOR_VOLTAGE,				\
235 		.id = LTC3589_ ## _name,				\
236 		.owner = THIS_MODULE,					\
237 		.vsel_reg = LTC3589_ ## _dtv1,				\
238 		.vsel_mask = 0x1f,					\
239 		.apply_reg = LTC3589_VCCR,				\
240 		.apply_bit = LTC3589_VCCR_ ## _name ## _GO,		\
241 		.enable_reg = LTC3589_OVEN,				\
242 		.enable_mask = (LTC3589_OVEN_ ## _name),		\
243 		.ramp_reg = LTC3589_VRRCR,				\
244 		.ramp_mask = LTC3589_VRRCR_ ## _name ## _RAMP_MASK,	\
245 		.ramp_delay_table = ltc3589_ramp_table,			\
246 		.n_ramp_values = ARRAY_SIZE(ltc3589_ramp_table),	\
247 	}
248 
249 
250 #define LTC3589_FIXED_REG(_name, _of_name)				\
251 	LTC3589_REG(_name, _of_name, fixed, LTC3589_OVEN_ ## _name, 0, 0)
252 
253 static const struct regulator_desc ltc3589_regulators[] = {
254 	LTC3589_LINEAR_REG(SW1, sw1, B1DTV1),
255 	LTC3589_LINEAR_REG(SW2, sw2, B2DTV1),
256 	LTC3589_LINEAR_REG(SW3, sw3, B3DTV1),
257 	LTC3589_FIXED_REG(BB_OUT, bb-out),
258 	LTC3589_REG(LDO1, ldo1, fixed_standby, 0, 0, 0),
259 	LTC3589_LINEAR_REG(LDO2, ldo2, L2DTV1),
260 	LTC3589_FIXED_REG(LDO3, ldo3),
261 	LTC3589_REG(LDO4, ldo4, table, LTC3589_OVEN_LDO4, LTC3589_L2DTV2, 0x60),
262 };
263 
ltc3589_writeable_reg(struct device * dev,unsigned int reg)264 static bool ltc3589_writeable_reg(struct device *dev, unsigned int reg)
265 {
266 	switch (reg) {
267 	case LTC3589_IRQSTAT:
268 	case LTC3589_SCR1:
269 	case LTC3589_OVEN:
270 	case LTC3589_SCR2:
271 	case LTC3589_VCCR:
272 	case LTC3589_CLIRQ:
273 	case LTC3589_B1DTV1:
274 	case LTC3589_B1DTV2:
275 	case LTC3589_VRRCR:
276 	case LTC3589_B2DTV1:
277 	case LTC3589_B2DTV2:
278 	case LTC3589_B3DTV1:
279 	case LTC3589_B3DTV2:
280 	case LTC3589_L2DTV1:
281 	case LTC3589_L2DTV2:
282 		return true;
283 	}
284 	return false;
285 }
286 
ltc3589_readable_reg(struct device * dev,unsigned int reg)287 static bool ltc3589_readable_reg(struct device *dev, unsigned int reg)
288 {
289 	switch (reg) {
290 	case LTC3589_IRQSTAT:
291 	case LTC3589_SCR1:
292 	case LTC3589_OVEN:
293 	case LTC3589_SCR2:
294 	case LTC3589_PGSTAT:
295 	case LTC3589_VCCR:
296 	case LTC3589_B1DTV1:
297 	case LTC3589_B1DTV2:
298 	case LTC3589_VRRCR:
299 	case LTC3589_B2DTV1:
300 	case LTC3589_B2DTV2:
301 	case LTC3589_B3DTV1:
302 	case LTC3589_B3DTV2:
303 	case LTC3589_L2DTV1:
304 	case LTC3589_L2DTV2:
305 		return true;
306 	}
307 	return false;
308 }
309 
ltc3589_volatile_reg(struct device * dev,unsigned int reg)310 static bool ltc3589_volatile_reg(struct device *dev, unsigned int reg)
311 {
312 	switch (reg) {
313 	case LTC3589_IRQSTAT:
314 	case LTC3589_PGSTAT:
315 	case LTC3589_VCCR:
316 		return true;
317 	}
318 	return false;
319 }
320 
321 static const struct reg_default ltc3589_reg_defaults[] = {
322 	{ LTC3589_SCR1,   0x00 },
323 	{ LTC3589_OVEN,   0x00 },
324 	{ LTC3589_SCR2,   0x00 },
325 	{ LTC3589_VCCR,   0x00 },
326 	{ LTC3589_B1DTV1, 0x19 },
327 	{ LTC3589_B1DTV2, 0x19 },
328 	{ LTC3589_VRRCR,  0xff },
329 	{ LTC3589_B2DTV1, 0x19 },
330 	{ LTC3589_B2DTV2, 0x19 },
331 	{ LTC3589_B3DTV1, 0x19 },
332 	{ LTC3589_B3DTV2, 0x19 },
333 	{ LTC3589_L2DTV1, 0x19 },
334 	{ LTC3589_L2DTV2, 0x19 },
335 };
336 
337 static const struct regmap_config ltc3589_regmap_config = {
338 	.reg_bits = 8,
339 	.val_bits = 8,
340 	.writeable_reg = ltc3589_writeable_reg,
341 	.readable_reg = ltc3589_readable_reg,
342 	.volatile_reg = ltc3589_volatile_reg,
343 	.max_register = LTC3589_L2DTV2,
344 	.reg_defaults = ltc3589_reg_defaults,
345 	.num_reg_defaults = ARRAY_SIZE(ltc3589_reg_defaults),
346 	.use_single_read = true,
347 	.use_single_write = true,
348 	.cache_type = REGCACHE_MAPLE,
349 };
350 
ltc3589_isr(int irq,void * dev_id)351 static irqreturn_t ltc3589_isr(int irq, void *dev_id)
352 {
353 	struct ltc3589 *ltc3589 = dev_id;
354 	unsigned int i, irqstat, event;
355 
356 	regmap_read(ltc3589->regmap, LTC3589_IRQSTAT, &irqstat);
357 
358 	if (irqstat & LTC3589_IRQSTAT_THERMAL_WARN) {
359 		event = REGULATOR_EVENT_OVER_TEMP;
360 		for (i = 0; i < LTC3589_NUM_REGULATORS; i++)
361 			regulator_notifier_call_chain(ltc3589->regulators[i],
362 						      event, NULL);
363 	}
364 
365 	if (irqstat & LTC3589_IRQSTAT_UNDERVOLT_WARN) {
366 		event = REGULATOR_EVENT_UNDER_VOLTAGE;
367 		for (i = 0; i < LTC3589_NUM_REGULATORS; i++)
368 			regulator_notifier_call_chain(ltc3589->regulators[i],
369 						      event, NULL);
370 	}
371 
372 	/* Clear warning condition */
373 	regmap_write(ltc3589->regmap, LTC3589_CLIRQ, 0);
374 
375 	return IRQ_HANDLED;
376 }
377 
ltc3589_probe(struct i2c_client * client)378 static int ltc3589_probe(struct i2c_client *client)
379 {
380 	struct device *dev = &client->dev;
381 	const struct ltc3589_info *info;
382 	struct regulator_desc *descs;
383 	struct ltc3589 *ltc3589;
384 	int i, ret;
385 
386 	ltc3589 = devm_kzalloc(dev, sizeof(*ltc3589), GFP_KERNEL);
387 	if (!ltc3589)
388 		return -ENOMEM;
389 
390 	i2c_set_clientdata(client, ltc3589);
391 	info = i2c_get_match_data(client);
392 	ltc3589->dev = dev;
393 
394 	descs = ltc3589->regulator_descs;
395 	memcpy(descs, ltc3589_regulators, sizeof(ltc3589_regulators));
396 	descs[LTC3589_LDO3].fixed_uV = info->fixed_uV;
397 	descs[LTC3589_LDO4].volt_table = info->volt_table;
398 
399 	ltc3589->regmap = devm_regmap_init_i2c(client, &ltc3589_regmap_config);
400 	if (IS_ERR(ltc3589->regmap)) {
401 		ret = PTR_ERR(ltc3589->regmap);
402 		dev_err(dev, "failed to initialize regmap: %d\n", ret);
403 		return ret;
404 	}
405 
406 	for (i = 0; i < LTC3589_NUM_REGULATORS; i++) {
407 		struct regulator_desc *desc = &ltc3589->regulator_descs[i];
408 		struct regulator_config config = { };
409 
410 		config.dev = dev;
411 		config.driver_data = ltc3589;
412 
413 		ltc3589->regulators[i] = devm_regulator_register(dev, desc,
414 								 &config);
415 		if (IS_ERR(ltc3589->regulators[i])) {
416 			ret = PTR_ERR(ltc3589->regulators[i]);
417 			dev_err(dev, "failed to register regulator %s: %d\n",
418 				desc->name, ret);
419 			return ret;
420 		}
421 	}
422 
423 	if (client->irq) {
424 		ret = devm_request_threaded_irq(dev, client->irq, NULL,
425 						ltc3589_isr,
426 						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
427 						client->name, ltc3589);
428 		if (ret) {
429 			dev_err(dev, "Failed to request IRQ: %d\n", ret);
430 			return ret;
431 		}
432 	}
433 
434 	return 0;
435 }
436 
437 static const struct ltc3589_info ltc3589_info = {
438 	.fixed_uV = 1800000,
439 	.volt_table = ltc3589_ldo4,
440 };
441 
442 static const struct ltc3589_info ltc3589_12_info = {
443 	.fixed_uV = 2800000,
444 	.volt_table = ltc3589_12_ldo4,
445 };
446 
447 static const struct i2c_device_id ltc3589_i2c_id[] = {
448 	{ "ltc3589",   (kernel_ulong_t)&ltc3589_info },
449 	{ "ltc3589-1", (kernel_ulong_t)&ltc3589_12_info },
450 	{ "ltc3589-2", (kernel_ulong_t)&ltc3589_12_info },
451 	{ }
452 };
453 MODULE_DEVICE_TABLE(i2c, ltc3589_i2c_id);
454 
455 static const struct of_device_id __maybe_unused ltc3589_of_match[] = {
456 	{ .compatible = "lltc,ltc3589",   .data = &ltc3589_info },
457 	{ .compatible = "lltc,ltc3589-1", .data = &ltc3589_12_info },
458 	{ .compatible = "lltc,ltc3589-2", .data = &ltc3589_12_info },
459 	{ }
460 };
461 MODULE_DEVICE_TABLE(of, ltc3589_of_match);
462 
463 static struct i2c_driver ltc3589_driver = {
464 	.driver = {
465 		.name = DRIVER_NAME,
466 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
467 		.of_match_table = of_match_ptr(ltc3589_of_match),
468 	},
469 	.probe = ltc3589_probe,
470 	.id_table = ltc3589_i2c_id,
471 };
472 module_i2c_driver(ltc3589_driver);
473 
474 MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");
475 MODULE_DESCRIPTION("Regulator driver for Linear Technology LTC3589(-1,2)");
476 MODULE_LICENSE("GPL v2");
477