1 /*
2  * da9211-regulator.c - Regulator device driver for DA9211
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/regulator/da9211.h>
28 #include "da9211-regulator.h"
29 
30 #define DA9211_BUCK_MODE_SLEEP	1
31 #define DA9211_BUCK_MODE_SYNC	2
32 #define DA9211_BUCK_MODE_AUTO	3
33 
34 /* DA9211 REGULATOR IDs */
35 #define DA9211_ID_BUCKA	0
36 #define DA9211_ID_BUCKB	1
37 
38 struct da9211 {
39 	struct device *dev;
40 	struct regmap *regmap;
41 	struct da9211_pdata *pdata;
42 	struct regulator_dev *rdev[DA9211_MAX_REGULATORS];
43 	int num_regulator;
44 	int chip_irq;
45 };
46 
47 static const struct regmap_range_cfg da9211_regmap_range[] = {
48 	{
49 		.selector_reg = DA9211_REG_PAGE_CON,
50 		.selector_mask  = DA9211_REG_PAGE_MASK,
51 		.selector_shift = DA9211_REG_PAGE_SHIFT,
52 		.window_start = 0,
53 		.window_len = 256,
54 		.range_min = 0,
55 		.range_max = 2*256,
56 	},
57 };
58 
59 static const struct regmap_config da9211_regmap_config = {
60 	.reg_bits = 8,
61 	.val_bits = 8,
62 	.max_register = 2 * 256,
63 	.ranges = da9211_regmap_range,
64 	.num_ranges = ARRAY_SIZE(da9211_regmap_range),
65 };
66 
67 /* Default limits measured in millivolts and milliamps */
68 #define DA9211_MIN_MV		300
69 #define DA9211_MAX_MV		1570
70 #define DA9211_STEP_MV		10
71 
72 /* Current limits for buck (uA) indices corresponds with register values */
73 static const int da9211_current_limits[] = {
74 	2000000, 2200000, 2400000, 2600000, 2800000, 3000000, 3200000, 3400000,
75 	3600000, 3800000, 4000000, 4200000, 4400000, 4600000, 4800000, 5000000
76 };
77 
78 static unsigned int da9211_buck_get_mode(struct regulator_dev *rdev)
79 {
80 	int id = rdev_get_id(rdev);
81 	struct da9211 *chip = rdev_get_drvdata(rdev);
82 	unsigned int data;
83 	int ret, mode = 0;
84 
85 	ret = regmap_read(chip->regmap, DA9211_REG_BUCKA_CONF+id, &data);
86 	if (ret < 0)
87 		return ret;
88 
89 	switch (data & 0x03) {
90 	case DA9211_BUCK_MODE_SYNC:
91 		mode = REGULATOR_MODE_FAST;
92 		break;
93 	case DA9211_BUCK_MODE_AUTO:
94 		mode = REGULATOR_MODE_NORMAL;
95 		break;
96 	case DA9211_BUCK_MODE_SLEEP:
97 		mode = REGULATOR_MODE_STANDBY;
98 		break;
99 	}
100 
101 	return mode;
102 }
103 
104 static int da9211_buck_set_mode(struct regulator_dev *rdev,
105 					unsigned int mode)
106 {
107 	int id = rdev_get_id(rdev);
108 	struct da9211 *chip = rdev_get_drvdata(rdev);
109 	int val = 0;
110 
111 	switch (mode) {
112 	case REGULATOR_MODE_FAST:
113 		val = DA9211_BUCK_MODE_SYNC;
114 		break;
115 	case REGULATOR_MODE_NORMAL:
116 		val = DA9211_BUCK_MODE_AUTO;
117 		break;
118 	case REGULATOR_MODE_STANDBY:
119 		val = DA9211_BUCK_MODE_SLEEP;
120 		break;
121 	}
122 
123 	return regmap_update_bits(chip->regmap, DA9211_REG_BUCKA_CONF+id,
124 					0x03, val);
125 }
126 
127 static int da9211_set_current_limit(struct regulator_dev *rdev, int min,
128 				    int max)
129 {
130 	int id = rdev_get_id(rdev);
131 	struct da9211 *chip = rdev_get_drvdata(rdev);
132 	int i;
133 
134 	/* search for closest to maximum */
135 	for (i = ARRAY_SIZE(da9211_current_limits)-1; i >= 0; i--) {
136 		if (min <= da9211_current_limits[i] &&
137 		    max >= da9211_current_limits[i]) {
138 				return regmap_update_bits(chip->regmap,
139 					DA9211_REG_BUCK_ILIM,
140 					(0x0F << id*4), (i << id*4));
141 		}
142 	}
143 
144 	return -EINVAL;
145 }
146 
147 static int da9211_get_current_limit(struct regulator_dev *rdev)
148 {
149 	int id = rdev_get_id(rdev);
150 	struct da9211 *chip = rdev_get_drvdata(rdev);
151 	unsigned int data;
152 	int ret;
153 
154 	ret = regmap_read(chip->regmap, DA9211_REG_BUCK_ILIM, &data);
155 	if (ret < 0)
156 		return ret;
157 
158 	/* select one of 16 values: 0000 (2000mA) to 1111 (5000mA) */
159 	data = (data >> id*4) & 0x0F;
160 	return da9211_current_limits[data];
161 }
162 
163 static struct regulator_ops da9211_buck_ops = {
164 	.get_mode = da9211_buck_get_mode,
165 	.set_mode = da9211_buck_set_mode,
166 	.enable = regulator_enable_regmap,
167 	.disable = regulator_disable_regmap,
168 	.is_enabled = regulator_is_enabled_regmap,
169 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
170 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
171 	.list_voltage = regulator_list_voltage_linear,
172 	.set_current_limit = da9211_set_current_limit,
173 	.get_current_limit = da9211_get_current_limit,
174 };
175 
176 #define DA9211_BUCK(_id) \
177 {\
178 	.name = #_id,\
179 	.ops = &da9211_buck_ops,\
180 	.type = REGULATOR_VOLTAGE,\
181 	.id = DA9211_ID_##_id,\
182 	.n_voltages = (DA9211_MAX_MV - DA9211_MIN_MV) / DA9211_STEP_MV + 1,\
183 	.min_uV = (DA9211_MIN_MV * 1000),\
184 	.uV_step = (DA9211_STEP_MV * 1000),\
185 	.enable_reg = DA9211_REG_BUCKA_CONT + DA9211_ID_##_id,\
186 	.enable_mask = DA9211_BUCKA_EN,\
187 	.vsel_reg = DA9211_REG_VBUCKA_A + DA9211_ID_##_id * 2,\
188 	.vsel_mask = DA9211_VBUCK_MASK,\
189 	.owner = THIS_MODULE,\
190 }
191 
192 static struct regulator_desc da9211_regulators[] = {
193 	DA9211_BUCK(BUCKA),
194 	DA9211_BUCK(BUCKB),
195 };
196 
197 static irqreturn_t da9211_irq_handler(int irq, void *data)
198 {
199 	struct da9211 *chip = data;
200 	int reg_val, err, ret = IRQ_NONE;
201 
202 	err = regmap_read(chip->regmap, DA9211_REG_EVENT_B, &reg_val);
203 	if (err < 0)
204 		goto error_i2c;
205 
206 	if (reg_val & DA9211_E_OV_CURR_A) {
207 		regulator_notifier_call_chain(chip->rdev[0],
208 			REGULATOR_EVENT_OVER_CURRENT,
209 			rdev_get_drvdata(chip->rdev[0]));
210 
211 		err = regmap_write(chip->regmap, DA9211_REG_EVENT_B,
212 			DA9211_E_OV_CURR_A);
213 		if (err < 0)
214 			goto error_i2c;
215 
216 		ret = IRQ_HANDLED;
217 	}
218 
219 	if (reg_val & DA9211_E_OV_CURR_B) {
220 		regulator_notifier_call_chain(chip->rdev[1],
221 			REGULATOR_EVENT_OVER_CURRENT,
222 			rdev_get_drvdata(chip->rdev[1]));
223 
224 		err = regmap_write(chip->regmap, DA9211_REG_EVENT_B,
225 			DA9211_E_OV_CURR_B);
226 		if (err < 0)
227 			goto error_i2c;
228 
229 		ret = IRQ_HANDLED;
230 	}
231 
232 	return ret;
233 
234 error_i2c:
235 	dev_err(chip->dev, "I2C error : %d\n", err);
236 	return IRQ_NONE;
237 }
238 
239 static int da9211_regulator_init(struct da9211 *chip)
240 {
241 	struct regulator_config config = { };
242 	int i, ret;
243 	unsigned int data;
244 
245 	ret = regmap_read(chip->regmap, DA9211_REG_CONFIG_E, &data);
246 	if (ret < 0) {
247 		dev_err(chip->dev, "Failed to read CONTROL_E reg: %d\n", ret);
248 		return ret;
249 	}
250 
251 	data &= DA9211_SLAVE_SEL;
252 	/* If configuration for 1/2 bucks is different between platform data
253 	 * and the register, driver should exit.
254 	 */
255 	if ((chip->pdata->num_buck == 2 && data == 0x40)
256 		|| (chip->pdata->num_buck == 1 && data == 0x00)) {
257 		if (data == 0)
258 			chip->num_regulator = 1;
259 		else
260 			chip->num_regulator = 2;
261 	} else {
262 		dev_err(chip->dev, "Configuration is mismatched\n");
263 		return -EINVAL;
264 	}
265 
266 	for (i = 0; i < chip->num_regulator; i++) {
267 		if (chip->pdata)
268 			config.init_data =
269 				&(chip->pdata->init_data[i]);
270 
271 		config.dev = chip->dev;
272 		config.driver_data = chip;
273 		config.regmap = chip->regmap;
274 
275 		chip->rdev[i] = devm_regulator_register(chip->dev,
276 			&da9211_regulators[i], &config);
277 		if (IS_ERR(chip->rdev[i])) {
278 			dev_err(chip->dev,
279 				"Failed to register DA9211 regulator\n");
280 			return PTR_ERR(chip->rdev[i]);
281 		}
282 
283 		if (chip->chip_irq != 0) {
284 			ret = regmap_update_bits(chip->regmap,
285 				DA9211_REG_MASK_B, DA9211_M_OV_CURR_A << i, 1);
286 			if (ret < 0) {
287 				dev_err(chip->dev,
288 					"Failed to update mask reg: %d\n", ret);
289 				return ret;
290 			}
291 		}
292 	}
293 
294 	return 0;
295 }
296 /*
297  * I2C driver interface functions
298  */
299 static int da9211_i2c_probe(struct i2c_client *i2c,
300 		const struct i2c_device_id *id)
301 {
302 	struct da9211 *chip;
303 	int error, ret;
304 
305 	chip = devm_kzalloc(&i2c->dev, sizeof(struct da9211), GFP_KERNEL);
306 
307 	chip->dev = &i2c->dev;
308 	chip->regmap = devm_regmap_init_i2c(i2c, &da9211_regmap_config);
309 	if (IS_ERR(chip->regmap)) {
310 		error = PTR_ERR(chip->regmap);
311 		dev_err(&i2c->dev, "Failed to allocate register map: %d\n",
312 			error);
313 		return error;
314 	}
315 
316 	i2c_set_clientdata(i2c, chip);
317 
318 	chip->pdata = i2c->dev.platform_data;
319 	if (!chip->pdata) {
320 		dev_err(&i2c->dev, "No platform init data supplied\n");
321 		return -ENODEV;
322 	}
323 
324 	chip->chip_irq = i2c->irq;
325 
326 	if (chip->chip_irq != 0) {
327 		ret = devm_request_threaded_irq(chip->dev, chip->chip_irq, NULL,
328 					da9211_irq_handler,
329 					IRQF_TRIGGER_LOW|IRQF_ONESHOT,
330 					"da9211", chip);
331 		if (ret != 0) {
332 			dev_err(chip->dev, "Failed to request IRQ: %d\n",
333 				chip->chip_irq);
334 			return ret;
335 		}
336 	} else {
337 		dev_warn(chip->dev, "No IRQ configured\n");
338 	}
339 
340 	ret = da9211_regulator_init(chip);
341 
342 	if (ret < 0)
343 		dev_err(&i2c->dev, "Failed to initialize regulator: %d\n", ret);
344 
345 	return ret;
346 }
347 
348 static const struct i2c_device_id da9211_i2c_id[] = {
349 	{"da9211", 0},
350 	{},
351 };
352 
353 MODULE_DEVICE_TABLE(i2c, da9211_i2c_id);
354 
355 static struct i2c_driver da9211_regulator_driver = {
356 	.driver = {
357 		.name = "da9211",
358 		.owner = THIS_MODULE,
359 	},
360 	.probe = da9211_i2c_probe,
361 	.id_table = da9211_i2c_id,
362 };
363 
364 module_i2c_driver(da9211_regulator_driver);
365 
366 MODULE_AUTHOR("James Ban <James.Ban.opensource@diasemi.com>");
367 MODULE_DESCRIPTION("Regulator device driver for Dialog DA9211");
368 MODULE_LICENSE("GPL v2");
369