1/*
  2 * da9211-regulator.c - Regulator device driver for DA9211/DA9213/DA9215
  3 * Copyright (C) 2015  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#define DA9215_DEVICE_ID	0x24
 36
 37#define DA9211_BUCK_MODE_SLEEP	1
 38#define DA9211_BUCK_MODE_SYNC	2
 39#define DA9211_BUCK_MODE_AUTO	3
 40
 41/* DA9211 REGULATOR IDs */
 42#define DA9211_ID_BUCKA	0
 43#define DA9211_ID_BUCKB	1
 44
 45struct da9211 {
 46	struct device *dev;
 47	struct regmap *regmap;
 48	struct da9211_pdata *pdata;
 49	struct regulator_dev *rdev[DA9211_MAX_REGULATORS];
 50	int num_regulator;
 51	int chip_irq;
 52	int chip_id;
 53};
 54
 55static const struct regmap_range_cfg da9211_regmap_range[] = {
 56	{
 57		.selector_reg = DA9211_REG_PAGE_CON,
 58		.selector_mask  = DA9211_REG_PAGE_MASK,
 59		.selector_shift = DA9211_REG_PAGE_SHIFT,
 60		.window_start = 0,
 61		.window_len = 256,
 62		.range_min = 0,
 63		.range_max = 5*128,
 64	},
 65};
 66
 67static const struct regmap_config da9211_regmap_config = {
 68	.reg_bits = 8,
 69	.val_bits = 8,
 70	.max_register = 5 * 128,
 71	.ranges = da9211_regmap_range,
 72	.num_ranges = ARRAY_SIZE(da9211_regmap_range),
 73};
 74
 75/* Default limits measured in millivolts and milliamps */
 76#define DA9211_MIN_MV		300
 77#define DA9211_MAX_MV		1570
 78#define DA9211_STEP_MV		10
 79
 80/* Current limits for DA9211 buck (uA) indices
 81 * corresponds with register values
 82 */
 83static const int da9211_current_limits[] = {
 84	2000000, 2200000, 2400000, 2600000, 2800000, 3000000, 3200000, 3400000,
 85	3600000, 3800000, 4000000, 4200000, 4400000, 4600000, 4800000, 5000000
 86};
 87/* Current limits for DA9213 buck (uA) indices
 88 * corresponds with register values
 89 */
 90static const int da9213_current_limits[] = {
 91	3000000, 3200000, 3400000, 3600000, 3800000, 4000000, 4200000, 4400000,
 92	4600000, 4800000, 5000000, 5200000, 5400000, 5600000, 5800000, 6000000
 93};
 94/* Current limits for DA9215 buck (uA) indices
 95 * corresponds with register values
 96 */
 97static const int da9215_current_limits[] = {
 98	4000000, 4200000, 4400000, 4600000, 4800000, 5000000, 5200000, 5400000,
 99	5600000, 5800000, 6000000, 6200000, 6400000, 6600000, 6800000, 7000000
100};
101
102static unsigned int da9211_buck_get_mode(struct regulator_dev *rdev)
103{
104	int id = rdev_get_id(rdev);
105	struct da9211 *chip = rdev_get_drvdata(rdev);
106	unsigned int data;
107	int ret, mode = 0;
108
109	ret = regmap_read(chip->regmap, DA9211_REG_BUCKA_CONF+id, &data);
110	if (ret < 0)
111		return ret;
112
113	switch (data & 0x03) {
114	case DA9211_BUCK_MODE_SYNC:
115		mode = REGULATOR_MODE_FAST;
116		break;
117	case DA9211_BUCK_MODE_AUTO:
118		mode = REGULATOR_MODE_NORMAL;
119		break;
120	case DA9211_BUCK_MODE_SLEEP:
121		mode = REGULATOR_MODE_STANDBY;
122		break;
123	}
124
125	return mode;
126}
127
128static int da9211_buck_set_mode(struct regulator_dev *rdev,
129					unsigned int mode)
130{
131	int id = rdev_get_id(rdev);
132	struct da9211 *chip = rdev_get_drvdata(rdev);
133	int val = 0;
134
135	switch (mode) {
136	case REGULATOR_MODE_FAST:
137		val = DA9211_BUCK_MODE_SYNC;
138		break;
139	case REGULATOR_MODE_NORMAL:
140		val = DA9211_BUCK_MODE_AUTO;
141		break;
142	case REGULATOR_MODE_STANDBY:
143		val = DA9211_BUCK_MODE_SLEEP;
144		break;
145	}
146
147	return regmap_update_bits(chip->regmap, DA9211_REG_BUCKA_CONF+id,
148					0x03, val);
149}
150
151static int da9211_set_current_limit(struct regulator_dev *rdev, int min,
152				    int max)
153{
154	int id = rdev_get_id(rdev);
155	struct da9211 *chip = rdev_get_drvdata(rdev);
156	int i, max_size;
157	const int *current_limits;
158
159	switch (chip->chip_id) {
160	case DA9211:
161		current_limits = da9211_current_limits;
162		max_size = ARRAY_SIZE(da9211_current_limits)-1;
163		break;
164	case DA9213:
165		current_limits = da9213_current_limits;
166		max_size = ARRAY_SIZE(da9213_current_limits)-1;
167		break;
168	case DA9215:
169		current_limits = da9215_current_limits;
170		max_size = ARRAY_SIZE(da9215_current_limits)-1;
171		break;
172	default:
173		return -EINVAL;
174	}
175
176	/* search for closest to maximum */
177	for (i = max_size; i >= 0; i--) {
178		if (min <= current_limits[i] &&
179		    max >= current_limits[i]) {
180				return regmap_update_bits(chip->regmap,
181					DA9211_REG_BUCK_ILIM,
182					(0x0F << id*4), (i << id*4));
183		}
184	}
185
186	return -EINVAL;
187}
188
189static int da9211_get_current_limit(struct regulator_dev *rdev)
190{
191	int id = rdev_get_id(rdev);
192	struct da9211 *chip = rdev_get_drvdata(rdev);
193	unsigned int data;
194	int ret;
195	const int *current_limits;
196
197	switch (chip->chip_id) {
198	case DA9211:
199		current_limits = da9211_current_limits;
200		break;
201	case DA9213:
202		current_limits = da9213_current_limits;
203		break;
204	case DA9215:
205		current_limits = da9215_current_limits;
206		break;
207	default:
208		return -EINVAL;
209	}
210
211	ret = regmap_read(chip->regmap, DA9211_REG_BUCK_ILIM, &data);
212	if (ret < 0)
213		return ret;
214
215	/* select one of 16 values: 0000 (2000mA or 3000mA)
216	 * to 1111 (5000mA or 6000mA).
217	 */
218	data = (data >> id*4) & 0x0F;
219	return current_limits[data];
220}
221
222static const struct regulator_ops da9211_buck_ops = {
223	.get_mode = da9211_buck_get_mode,
224	.set_mode = da9211_buck_set_mode,
225	.enable = regulator_enable_regmap,
226	.disable = regulator_disable_regmap,
227	.is_enabled = regulator_is_enabled_regmap,
228	.set_voltage_sel = regulator_set_voltage_sel_regmap,
229	.get_voltage_sel = regulator_get_voltage_sel_regmap,
230	.list_voltage = regulator_list_voltage_linear,
231	.set_current_limit = da9211_set_current_limit,
232	.get_current_limit = da9211_get_current_limit,
233};
234
235#define DA9211_BUCK(_id) \
236{\
237	.name = #_id,\
238	.ops = &da9211_buck_ops,\
239	.type = REGULATOR_VOLTAGE,\
240	.id = DA9211_ID_##_id,\
241	.n_voltages = (DA9211_MAX_MV - DA9211_MIN_MV) / DA9211_STEP_MV + 1,\
242	.min_uV = (DA9211_MIN_MV * 1000),\
243	.uV_step = (DA9211_STEP_MV * 1000),\
244	.enable_reg = DA9211_REG_BUCKA_CONT + DA9211_ID_##_id,\
245	.enable_mask = DA9211_BUCKA_EN,\
246	.vsel_reg = DA9211_REG_VBUCKA_A + DA9211_ID_##_id * 2,\
247	.vsel_mask = DA9211_VBUCK_MASK,\
248	.owner = THIS_MODULE,\
249}
250
251static struct regulator_desc da9211_regulators[] = {
252	DA9211_BUCK(BUCKA),
253	DA9211_BUCK(BUCKB),
254};
255
256#ifdef CONFIG_OF
257static struct of_regulator_match da9211_matches[] = {
258	[DA9211_ID_BUCKA] = { .name = "BUCKA" },
259	[DA9211_ID_BUCKB] = { .name = "BUCKB" },
260	};
261
262static struct da9211_pdata *da9211_parse_regulators_dt(
263		struct device *dev)
264{
265	struct da9211_pdata *pdata;
266	struct device_node *node;
267	int i, num, n;
268
269	node = of_get_child_by_name(dev->of_node, "regulators");
270	if (!node) {
271		dev_err(dev, "regulators node not found\n");
272		return ERR_PTR(-ENODEV);
273	}
274
275	num = of_regulator_match(dev, node, da9211_matches,
276				 ARRAY_SIZE(da9211_matches));
277	of_node_put(node);
278	if (num < 0) {
279		dev_err(dev, "Failed to match regulators\n");
280		return ERR_PTR(-EINVAL);
281	}
282
283	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
284	if (!pdata)
285		return ERR_PTR(-ENOMEM);
286
287	pdata->num_buck = num;
288
289	n = 0;
290	for (i = 0; i < ARRAY_SIZE(da9211_matches); i++) {
291		if (!da9211_matches[i].init_data)
292			continue;
293
294		pdata->init_data[n] = da9211_matches[i].init_data;
295		pdata->reg_node[n] = da9211_matches[i].of_node;
296		pdata->gpio_ren[n] =
297			of_get_named_gpio(da9211_matches[i].of_node,
298				"enable-gpios", 0);
299		n++;
300	}
301
302	return pdata;
303}
304#else
305static struct da9211_pdata *da9211_parse_regulators_dt(
306		struct device *dev)
307{
308	return ERR_PTR(-ENODEV);
309}
310#endif
311
312static irqreturn_t da9211_irq_handler(int irq, void *data)
313{
314	struct da9211 *chip = data;
315	int reg_val, err, ret = IRQ_NONE;
316
317	err = regmap_read(chip->regmap, DA9211_REG_EVENT_B, &reg_val);
318	if (err < 0)
319		goto error_i2c;
320
321	if (reg_val & DA9211_E_OV_CURR_A) {
322		regulator_notifier_call_chain(chip->rdev[0],
323			REGULATOR_EVENT_OVER_CURRENT, NULL);
324
325		err = regmap_write(chip->regmap, DA9211_REG_EVENT_B,
326			DA9211_E_OV_CURR_A);
327		if (err < 0)
328			goto error_i2c;
329
330		ret = IRQ_HANDLED;
331	}
332
333	if (reg_val & DA9211_E_OV_CURR_B) {
334		regulator_notifier_call_chain(chip->rdev[1],
335			REGULATOR_EVENT_OVER_CURRENT, NULL);
336
337		err = regmap_write(chip->regmap, DA9211_REG_EVENT_B,
338			DA9211_E_OV_CURR_B);
339		if (err < 0)
340			goto error_i2c;
341
342		ret = IRQ_HANDLED;
343	}
344
345	return ret;
346
347error_i2c:
348	dev_err(chip->dev, "I2C error : %d\n", err);
349	return IRQ_NONE;
350}
351
352static int da9211_regulator_init(struct da9211 *chip)
353{
354	struct regulator_config config = { };
355	int i, ret;
356	unsigned int data;
357
358	ret = regmap_read(chip->regmap, DA9211_REG_CONFIG_E, &data);
359	if (ret < 0) {
360		dev_err(chip->dev, "Failed to read CONFIG_E reg: %d\n", ret);
361		return ret;
362	}
363
364	data &= DA9211_SLAVE_SEL;
365	/* If configuration for 1/2 bucks is different between platform data
366	 * and the register, driver should exit.
367	 */
368	if (chip->pdata->num_buck == 1 && data == 0x00)
369		chip->num_regulator = 1;
370	else if (chip->pdata->num_buck == 2 && data != 0x00)
371		chip->num_regulator = 2;
372	else {
373		dev_err(chip->dev, "Configuration is mismatched\n");
374		return -EINVAL;
375	}
376
377	for (i = 0; i < chip->num_regulator; i++) {
378		config.init_data = chip->pdata->init_data[i];
379		config.dev = chip->dev;
380		config.driver_data = chip;
381		config.regmap = chip->regmap;
382		config.of_node = chip->pdata->reg_node[i];
383
384		if (gpio_is_valid(chip->pdata->gpio_ren[i])) {
385			config.ena_gpio = chip->pdata->gpio_ren[i];
386			config.ena_gpio_initialized = true;
387		} else {
388			config.ena_gpio = -EINVAL;
389			config.ena_gpio_initialized = false;
390		}
391
392		chip->rdev[i] = devm_regulator_register(chip->dev,
393			&da9211_regulators[i], &config);
394		if (IS_ERR(chip->rdev[i])) {
395			dev_err(chip->dev,
396				"Failed to register DA9211 regulator\n");
397			return PTR_ERR(chip->rdev[i]);
398		}
399
400		if (chip->chip_irq != 0) {
401			ret = regmap_update_bits(chip->regmap,
402				DA9211_REG_MASK_B, DA9211_M_OV_CURR_A << i, 0);
403			if (ret < 0) {
404				dev_err(chip->dev,
405					"Failed to update mask reg: %d\n", ret);
406				return ret;
407			}
408		}
409	}
410
411	return 0;
412}
413
414/*
415 * I2C driver interface functions
416 */
417static int da9211_i2c_probe(struct i2c_client *i2c,
418		const struct i2c_device_id *id)
419{
420	struct da9211 *chip;
421	int error, ret;
422	unsigned int data;
423
424	chip = devm_kzalloc(&i2c->dev, sizeof(struct da9211), GFP_KERNEL);
425	if (!chip)
426		return -ENOMEM;
427
428	chip->dev = &i2c->dev;
429	chip->regmap = devm_regmap_init_i2c(i2c, &da9211_regmap_config);
430	if (IS_ERR(chip->regmap)) {
431		error = PTR_ERR(chip->regmap);
432		dev_err(chip->dev, "Failed to allocate register map: %d\n",
433			error);
434		return error;
435	}
436
437	i2c_set_clientdata(i2c, chip);
438
439	chip->pdata = i2c->dev.platform_data;
440
441	ret = regmap_read(chip->regmap, DA9211_REG_DEVICE_ID, &data);
442	if (ret < 0) {
443		dev_err(chip->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
444		return ret;
445	}
446
447	switch (data) {
448	case DA9211_DEVICE_ID:
449		chip->chip_id = DA9211;
450		break;
451	case DA9213_DEVICE_ID:
452		chip->chip_id = DA9213;
453		break;
454	case DA9215_DEVICE_ID:
455		chip->chip_id = DA9215;
456		break;
457	default:
458		dev_err(chip->dev, "Unsupported device id = 0x%x.\n", data);
459		return -ENODEV;
460	}
461
462	if (!chip->pdata)
463		chip->pdata = da9211_parse_regulators_dt(chip->dev);
464
465	if (IS_ERR(chip->pdata)) {
466		dev_err(chip->dev, "No regulators defined for the platform\n");
467		return PTR_ERR(chip->pdata);
468	}
469
470	chip->chip_irq = i2c->irq;
471
472	if (chip->chip_irq != 0) {
473		ret = devm_request_threaded_irq(chip->dev, chip->chip_irq, NULL,
474					da9211_irq_handler,
475					IRQF_TRIGGER_LOW|IRQF_ONESHOT,
476					"da9211", chip);
477		if (ret != 0) {
478			dev_err(chip->dev, "Failed to request IRQ: %d\n",
479				chip->chip_irq);
480			return ret;
481		}
482	} else {
483		dev_warn(chip->dev, "No IRQ configured\n");
484	}
485
486	ret = da9211_regulator_init(chip);
487
488	if (ret < 0)
489		dev_err(chip->dev, "Failed to initialize regulator: %d\n", ret);
490
491	return ret;
492}
493
494static const struct i2c_device_id da9211_i2c_id[] = {
495	{"da9211", DA9211},
496	{"da9213", DA9213},
497	{"da9215", DA9215},
498	{},
499};
500MODULE_DEVICE_TABLE(i2c, da9211_i2c_id);
501
502#ifdef CONFIG_OF
503static const struct of_device_id da9211_dt_ids[] = {
504	{ .compatible = "dlg,da9211", .data = &da9211_i2c_id[0] },
505	{ .compatible = "dlg,da9213", .data = &da9211_i2c_id[1] },
506	{ .compatible = "dlg,da9215", .data = &da9211_i2c_id[2] },
507	{},
508};
509MODULE_DEVICE_TABLE(of, da9211_dt_ids);
510#endif
511
512static struct i2c_driver da9211_regulator_driver = {
513	.driver = {
514		.name = "da9211",
515		.of_match_table = of_match_ptr(da9211_dt_ids),
516	},
517	.probe = da9211_i2c_probe,
518	.id_table = da9211_i2c_id,
519};
520
521module_i2c_driver(da9211_regulator_driver);
522
523MODULE_AUTHOR("James Ban <James.Ban.opensource@diasemi.com>");
524MODULE_DESCRIPTION("Regulator device driver for Dialog DA9211/DA9213/DA9215");
525MODULE_LICENSE("GPL");