1/*
2 * da9211-regulator.c - Regulator device driver for DA9211/DA9213
3 * Copyright (C) 2014  Dialog Semiconductor Ltd.
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13 * Library General Public License for more details.
14 */
15
16#include <linux/err.h>
17#include <linux/gpio.h>
18#include <linux/i2c.h>
19#include <linux/module.h>
20#include <linux/init.h>
21#include <linux/slab.h>
22#include <linux/regulator/driver.h>
23#include <linux/regulator/machine.h>
24#include <linux/regmap.h>
25#include <linux/irq.h>
26#include <linux/interrupt.h>
27#include <linux/of_gpio.h>
28#include <linux/regulator/of_regulator.h>
29#include <linux/regulator/da9211.h>
30#include "da9211-regulator.h"
31
32/* DEVICE IDs */
33#define DA9211_DEVICE_ID	0x22
34#define DA9213_DEVICE_ID	0x23
35
36#define DA9211_BUCK_MODE_SLEEP	1
37#define DA9211_BUCK_MODE_SYNC	2
38#define DA9211_BUCK_MODE_AUTO	3
39
40/* DA9211 REGULATOR IDs */
41#define DA9211_ID_BUCKA	0
42#define DA9211_ID_BUCKB	1
43
44struct da9211 {
45	struct device *dev;
46	struct regmap *regmap;
47	struct da9211_pdata *pdata;
48	struct regulator_dev *rdev[DA9211_MAX_REGULATORS];
49	int num_regulator;
50	int chip_irq;
51	int chip_id;
52};
53
54static const struct regmap_range_cfg da9211_regmap_range[] = {
55	{
56		.selector_reg = DA9211_REG_PAGE_CON,
57		.selector_mask  = DA9211_REG_PAGE_MASK,
58		.selector_shift = DA9211_REG_PAGE_SHIFT,
59		.window_start = 0,
60		.window_len = 256,
61		.range_min = 0,
62		.range_max = 5*128,
63	},
64};
65
66static const struct regmap_config da9211_regmap_config = {
67	.reg_bits = 8,
68	.val_bits = 8,
69	.max_register = 5 * 128,
70	.ranges = da9211_regmap_range,
71	.num_ranges = ARRAY_SIZE(da9211_regmap_range),
72};
73
74/* Default limits measured in millivolts and milliamps */
75#define DA9211_MIN_MV		300
76#define DA9211_MAX_MV		1570
77#define DA9211_STEP_MV		10
78
79/* Current limits for DA9211 buck (uA) indices
80 * corresponds with register values
81 */
82static const int da9211_current_limits[] = {
83	2000000, 2200000, 2400000, 2600000, 2800000, 3000000, 3200000, 3400000,
84	3600000, 3800000, 4000000, 4200000, 4400000, 4600000, 4800000, 5000000
85};
86/* Current limits for DA9213 buck (uA) indices
87 * corresponds with register values
88 */
89static const int da9213_current_limits[] = {
90	3000000, 3200000, 3400000, 3600000, 3800000, 4000000, 4200000, 4400000,
91	4600000, 4800000, 5000000, 5200000, 5400000, 5600000, 5800000, 6000000
92};
93
94static unsigned int da9211_buck_get_mode(struct regulator_dev *rdev)
95{
96	int id = rdev_get_id(rdev);
97	struct da9211 *chip = rdev_get_drvdata(rdev);
98	unsigned int data;
99	int ret, mode = 0;
100
101	ret = regmap_read(chip->regmap, DA9211_REG_BUCKA_CONF+id, &data);
102	if (ret < 0)
103		return ret;
104
105	switch (data & 0x03) {
106	case DA9211_BUCK_MODE_SYNC:
107		mode = REGULATOR_MODE_FAST;
108		break;
109	case DA9211_BUCK_MODE_AUTO:
110		mode = REGULATOR_MODE_NORMAL;
111		break;
112	case DA9211_BUCK_MODE_SLEEP:
113		mode = REGULATOR_MODE_STANDBY;
114		break;
115	}
116
117	return mode;
118}
119
120static int da9211_buck_set_mode(struct regulator_dev *rdev,
121					unsigned int mode)
122{
123	int id = rdev_get_id(rdev);
124	struct da9211 *chip = rdev_get_drvdata(rdev);
125	int val = 0;
126
127	switch (mode) {
128	case REGULATOR_MODE_FAST:
129		val = DA9211_BUCK_MODE_SYNC;
130		break;
131	case REGULATOR_MODE_NORMAL:
132		val = DA9211_BUCK_MODE_AUTO;
133		break;
134	case REGULATOR_MODE_STANDBY:
135		val = DA9211_BUCK_MODE_SLEEP;
136		break;
137	}
138
139	return regmap_update_bits(chip->regmap, DA9211_REG_BUCKA_CONF+id,
140					0x03, val);
141}
142
143static int da9211_set_current_limit(struct regulator_dev *rdev, int min,
144				    int max)
145{
146	int id = rdev_get_id(rdev);
147	struct da9211 *chip = rdev_get_drvdata(rdev);
148	int i, max_size;
149	const int *current_limits;
150
151	switch (chip->chip_id) {
152	case DA9211:
153		current_limits = da9211_current_limits;
154		max_size = ARRAY_SIZE(da9211_current_limits)-1;
155		break;
156	case DA9213:
157		current_limits = da9213_current_limits;
158		max_size = ARRAY_SIZE(da9213_current_limits)-1;
159		break;
160	default:
161		return -EINVAL;
162	}
163
164	/* search for closest to maximum */
165	for (i = max_size; i >= 0; i--) {
166		if (min <= current_limits[i] &&
167		    max >= current_limits[i]) {
168				return regmap_update_bits(chip->regmap,
169					DA9211_REG_BUCK_ILIM,
170					(0x0F << id*4), (i << id*4));
171		}
172	}
173
174	return -EINVAL;
175}
176
177static int da9211_get_current_limit(struct regulator_dev *rdev)
178{
179	int id = rdev_get_id(rdev);
180	struct da9211 *chip = rdev_get_drvdata(rdev);
181	unsigned int data;
182	int ret;
183	const int *current_limits;
184
185	switch (chip->chip_id) {
186	case DA9211:
187		current_limits = da9211_current_limits;
188		break;
189	case DA9213:
190		current_limits = da9213_current_limits;
191		break;
192	default:
193		return -EINVAL;
194	}
195
196	ret = regmap_read(chip->regmap, DA9211_REG_BUCK_ILIM, &data);
197	if (ret < 0)
198		return ret;
199
200	/* select one of 16 values: 0000 (2000mA or 3000mA)
201	 * to 1111 (5000mA or 6000mA).
202	 */
203	data = (data >> id*4) & 0x0F;
204	return current_limits[data];
205}
206
207static struct regulator_ops da9211_buck_ops = {
208	.get_mode = da9211_buck_get_mode,
209	.set_mode = da9211_buck_set_mode,
210	.enable = regulator_enable_regmap,
211	.disable = regulator_disable_regmap,
212	.is_enabled = regulator_is_enabled_regmap,
213	.set_voltage_sel = regulator_set_voltage_sel_regmap,
214	.get_voltage_sel = regulator_get_voltage_sel_regmap,
215	.list_voltage = regulator_list_voltage_linear,
216	.set_current_limit = da9211_set_current_limit,
217	.get_current_limit = da9211_get_current_limit,
218};
219
220#define DA9211_BUCK(_id) \
221{\
222	.name = #_id,\
223	.ops = &da9211_buck_ops,\
224	.type = REGULATOR_VOLTAGE,\
225	.id = DA9211_ID_##_id,\
226	.n_voltages = (DA9211_MAX_MV - DA9211_MIN_MV) / DA9211_STEP_MV + 1,\
227	.min_uV = (DA9211_MIN_MV * 1000),\
228	.uV_step = (DA9211_STEP_MV * 1000),\
229	.enable_reg = DA9211_REG_BUCKA_CONT + DA9211_ID_##_id,\
230	.enable_mask = DA9211_BUCKA_EN,\
231	.vsel_reg = DA9211_REG_VBUCKA_A + DA9211_ID_##_id * 2,\
232	.vsel_mask = DA9211_VBUCK_MASK,\
233	.owner = THIS_MODULE,\
234}
235
236static struct regulator_desc da9211_regulators[] = {
237	DA9211_BUCK(BUCKA),
238	DA9211_BUCK(BUCKB),
239};
240
241#ifdef CONFIG_OF
242static struct of_regulator_match da9211_matches[] = {
243	[DA9211_ID_BUCKA] = { .name = "BUCKA" },
244	[DA9211_ID_BUCKB] = { .name = "BUCKB" },
245	};
246
247static struct da9211_pdata *da9211_parse_regulators_dt(
248		struct device *dev)
249{
250	struct da9211_pdata *pdata;
251	struct device_node *node;
252	int i, num, n;
253
254	node = of_get_child_by_name(dev->of_node, "regulators");
255	if (!node) {
256		dev_err(dev, "regulators node not found\n");
257		return ERR_PTR(-ENODEV);
258	}
259
260	num = of_regulator_match(dev, node, da9211_matches,
261				 ARRAY_SIZE(da9211_matches));
262	of_node_put(node);
263	if (num < 0) {
264		dev_err(dev, "Failed to match regulators\n");
265		return ERR_PTR(-EINVAL);
266	}
267
268	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
269	if (!pdata)
270		return ERR_PTR(-ENOMEM);
271
272	pdata->num_buck = num;
273
274	n = 0;
275	for (i = 0; i < ARRAY_SIZE(da9211_matches); i++) {
276		if (!da9211_matches[i].init_data)
277			continue;
278
279		pdata->init_data[n] = da9211_matches[i].init_data;
280		pdata->reg_node[n] = da9211_matches[i].of_node;
281		pdata->gpio_ren[n] =
282			of_get_named_gpio(da9211_matches[i].of_node,
283				"enable-gpios", 0);
284		n++;
285	}
286
287	return pdata;
288}
289#else
290static struct da9211_pdata *da9211_parse_regulators_dt(
291		struct device *dev)
292{
293	return ERR_PTR(-ENODEV);
294}
295#endif
296
297static irqreturn_t da9211_irq_handler(int irq, void *data)
298{
299	struct da9211 *chip = data;
300	int reg_val, err, ret = IRQ_NONE;
301
302	err = regmap_read(chip->regmap, DA9211_REG_EVENT_B, &reg_val);
303	if (err < 0)
304		goto error_i2c;
305
306	if (reg_val & DA9211_E_OV_CURR_A) {
307		regulator_notifier_call_chain(chip->rdev[0],
308			REGULATOR_EVENT_OVER_CURRENT, NULL);
309
310		err = regmap_write(chip->regmap, DA9211_REG_EVENT_B,
311			DA9211_E_OV_CURR_A);
312		if (err < 0)
313			goto error_i2c;
314
315		ret = IRQ_HANDLED;
316	}
317
318	if (reg_val & DA9211_E_OV_CURR_B) {
319		regulator_notifier_call_chain(chip->rdev[1],
320			REGULATOR_EVENT_OVER_CURRENT, NULL);
321
322		err = regmap_write(chip->regmap, DA9211_REG_EVENT_B,
323			DA9211_E_OV_CURR_B);
324		if (err < 0)
325			goto error_i2c;
326
327		ret = IRQ_HANDLED;
328	}
329
330	return ret;
331
332error_i2c:
333	dev_err(chip->dev, "I2C error : %d\n", err);
334	return IRQ_NONE;
335}
336
337static int da9211_regulator_init(struct da9211 *chip)
338{
339	struct regulator_config config = { };
340	int i, ret;
341	unsigned int data;
342
343	ret = regmap_read(chip->regmap, DA9211_REG_CONFIG_E, &data);
344	if (ret < 0) {
345		dev_err(chip->dev, "Failed to read CONFIG_E reg: %d\n", ret);
346		return ret;
347	}
348
349	data &= DA9211_SLAVE_SEL;
350	/* If configuration for 1/2 bucks is different between platform data
351	 * and the register, driver should exit.
352	 */
353	if ((chip->pdata->num_buck == 2 && data == 0x40)
354		|| (chip->pdata->num_buck == 1 && data == 0x00)) {
355		if (data == 0)
356			chip->num_regulator = 1;
357		else
358			chip->num_regulator = 2;
359	} else {
360		dev_err(chip->dev, "Configuration is mismatched\n");
361		return -EINVAL;
362	}
363
364	for (i = 0; i < chip->num_regulator; i++) {
365		config.init_data = chip->pdata->init_data[i];
366		config.dev = chip->dev;
367		config.driver_data = chip;
368		config.regmap = chip->regmap;
369		config.of_node = chip->pdata->reg_node[i];
370
371		if (gpio_is_valid(chip->pdata->gpio_ren[i])) {
372			config.ena_gpio = chip->pdata->gpio_ren[i];
373			config.ena_gpio_initialized = true;
374		} else {
375			config.ena_gpio = -EINVAL;
376			config.ena_gpio_initialized = false;
377		}
378
379		chip->rdev[i] = devm_regulator_register(chip->dev,
380			&da9211_regulators[i], &config);
381		if (IS_ERR(chip->rdev[i])) {
382			dev_err(chip->dev,
383				"Failed to register DA9211 regulator\n");
384			return PTR_ERR(chip->rdev[i]);
385		}
386
387		if (chip->chip_irq != 0) {
388			ret = regmap_update_bits(chip->regmap,
389				DA9211_REG_MASK_B, DA9211_M_OV_CURR_A << i, 0);
390			if (ret < 0) {
391				dev_err(chip->dev,
392					"Failed to update mask reg: %d\n", ret);
393				return ret;
394			}
395		}
396	}
397
398	return 0;
399}
400
401/*
402 * I2C driver interface functions
403 */
404static int da9211_i2c_probe(struct i2c_client *i2c,
405		const struct i2c_device_id *id)
406{
407	struct da9211 *chip;
408	int error, ret;
409	unsigned int data;
410
411	chip = devm_kzalloc(&i2c->dev, sizeof(struct da9211), GFP_KERNEL);
412	if (!chip)
413		return -ENOMEM;
414
415	chip->dev = &i2c->dev;
416	chip->regmap = devm_regmap_init_i2c(i2c, &da9211_regmap_config);
417	if (IS_ERR(chip->regmap)) {
418		error = PTR_ERR(chip->regmap);
419		dev_err(chip->dev, "Failed to allocate register map: %d\n",
420			error);
421		return error;
422	}
423
424	i2c_set_clientdata(i2c, chip);
425
426	chip->pdata = i2c->dev.platform_data;
427
428	ret = regmap_read(chip->regmap, DA9211_REG_DEVICE_ID, &data);
429	if (ret < 0) {
430		dev_err(chip->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
431		return ret;
432	}
433
434	switch (data) {
435	case DA9211_DEVICE_ID:
436		chip->chip_id = DA9211;
437		break;
438	case DA9213_DEVICE_ID:
439		chip->chip_id = DA9213;
440		break;
441	default:
442		dev_err(chip->dev, "Unsupported device id = 0x%x.\n", data);
443		return -ENODEV;
444	}
445
446	if (!chip->pdata)
447		chip->pdata = da9211_parse_regulators_dt(chip->dev);
448
449	if (IS_ERR(chip->pdata)) {
450		dev_err(chip->dev, "No regulators defined for the platform\n");
451		return PTR_ERR(chip->pdata);
452	}
453
454	chip->chip_irq = i2c->irq;
455
456	if (chip->chip_irq != 0) {
457		ret = devm_request_threaded_irq(chip->dev, chip->chip_irq, NULL,
458					da9211_irq_handler,
459					IRQF_TRIGGER_LOW|IRQF_ONESHOT,
460					"da9211", chip);
461		if (ret != 0) {
462			dev_err(chip->dev, "Failed to request IRQ: %d\n",
463				chip->chip_irq);
464			return ret;
465		}
466	} else {
467		dev_warn(chip->dev, "No IRQ configured\n");
468	}
469
470	ret = da9211_regulator_init(chip);
471
472	if (ret < 0)
473		dev_err(chip->dev, "Failed to initialize regulator: %d\n", ret);
474
475	return ret;
476}
477
478static const struct i2c_device_id da9211_i2c_id[] = {
479	{"da9211", DA9211},
480	{"da9213", DA9213},
481	{},
482};
483MODULE_DEVICE_TABLE(i2c, da9211_i2c_id);
484
485#ifdef CONFIG_OF
486static const struct of_device_id da9211_dt_ids[] = {
487	{ .compatible = "dlg,da9211", .data = &da9211_i2c_id[0] },
488	{ .compatible = "dlg,da9213", .data = &da9211_i2c_id[1] },
489	{},
490};
491MODULE_DEVICE_TABLE(of, da9211_dt_ids);
492#endif
493
494static struct i2c_driver da9211_regulator_driver = {
495	.driver = {
496		.name = "da9211",
497		.owner = THIS_MODULE,
498		.of_match_table = of_match_ptr(da9211_dt_ids),
499	},
500	.probe = da9211_i2c_probe,
501	.id_table = da9211_i2c_id,
502};
503
504module_i2c_driver(da9211_regulator_driver);
505
506MODULE_AUTHOR("James Ban <James.Ban.opensource@diasemi.com>");
507MODULE_DESCRIPTION("Regulator device driver for Dialog DA9211/DA9213");
508MODULE_LICENSE("GPL v2");
509