xref: /openbmc/linux/drivers/regulator/fan53555.c (revision eb3fcf00)
1 /*
2  * FAN53555 Fairchild Digitally Programmable TinyBuck Regulator Driver.
3  *
4  * Supported Part Numbers:
5  * FAN53555UC00X/01X/03X/04X/05X
6  *
7  * Copyright (c) 2012 Marvell Technology Ltd.
8  * Yunfan Zhang <yfzhang@marvell.com>
9  *
10  * This package is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  *
14  */
15 #include <linux/module.h>
16 #include <linux/param.h>
17 #include <linux/err.h>
18 #include <linux/platform_device.h>
19 #include <linux/regulator/driver.h>
20 #include <linux/regulator/machine.h>
21 #include <linux/regulator/of_regulator.h>
22 #include <linux/of_device.h>
23 #include <linux/i2c.h>
24 #include <linux/slab.h>
25 #include <linux/regmap.h>
26 #include <linux/regulator/fan53555.h>
27 
28 /* Voltage setting */
29 #define FAN53555_VSEL0		0x00
30 #define FAN53555_VSEL1		0x01
31 /* Control register */
32 #define FAN53555_CONTROL	0x02
33 /* IC Type */
34 #define FAN53555_ID1		0x03
35 /* IC mask version */
36 #define FAN53555_ID2		0x04
37 /* Monitor register */
38 #define FAN53555_MONITOR	0x05
39 
40 /* VSEL bit definitions */
41 #define VSEL_BUCK_EN	(1 << 7)
42 #define VSEL_MODE		(1 << 6)
43 #define VSEL_NSEL_MASK	0x3F
44 /* Chip ID and Verison */
45 #define DIE_ID		0x0F	/* ID1 */
46 #define DIE_REV		0x0F	/* ID2 */
47 /* Control bit definitions */
48 #define CTL_OUTPUT_DISCHG	(1 << 7)
49 #define CTL_SLEW_MASK		(0x7 << 4)
50 #define CTL_SLEW_SHIFT		4
51 #define CTL_RESET			(1 << 2)
52 
53 #define FAN53555_NVOLTAGES	64	/* Numbers of voltages */
54 
55 enum fan53555_vendor {
56 	FAN53555_VENDOR_FAIRCHILD = 0,
57 	FAN53555_VENDOR_SILERGY,
58 };
59 
60 /* IC Type */
61 enum {
62 	FAN53555_CHIP_ID_00 = 0,
63 	FAN53555_CHIP_ID_01,
64 	FAN53555_CHIP_ID_02,
65 	FAN53555_CHIP_ID_03,
66 	FAN53555_CHIP_ID_04,
67 	FAN53555_CHIP_ID_05,
68 };
69 
70 enum {
71 	SILERGY_SYR82X = 8,
72 };
73 
74 struct fan53555_device_info {
75 	enum fan53555_vendor vendor;
76 	struct regmap *regmap;
77 	struct device *dev;
78 	struct regulator_desc desc;
79 	struct regulator_dev *rdev;
80 	struct regulator_init_data *regulator;
81 	/* IC Type and Rev */
82 	int chip_id;
83 	int chip_rev;
84 	/* Voltage setting register */
85 	unsigned int vol_reg;
86 	unsigned int sleep_reg;
87 	/* Voltage range and step(linear) */
88 	unsigned int vsel_min;
89 	unsigned int vsel_step;
90 	/* Voltage slew rate limiting */
91 	unsigned int slew_rate;
92 	/* Sleep voltage cache */
93 	unsigned int sleep_vol_cache;
94 };
95 
96 static int fan53555_set_suspend_voltage(struct regulator_dev *rdev, int uV)
97 {
98 	struct fan53555_device_info *di = rdev_get_drvdata(rdev);
99 	int ret;
100 
101 	if (di->sleep_vol_cache == uV)
102 		return 0;
103 	ret = regulator_map_voltage_linear(rdev, uV, uV);
104 	if (ret < 0)
105 		return ret;
106 	ret = regmap_update_bits(di->regmap, di->sleep_reg,
107 					VSEL_NSEL_MASK, ret);
108 	if (ret < 0)
109 		return ret;
110 	/* Cache the sleep voltage setting.
111 	 * Might not be the real voltage which is rounded */
112 	di->sleep_vol_cache = uV;
113 
114 	return 0;
115 }
116 
117 static int fan53555_set_mode(struct regulator_dev *rdev, unsigned int mode)
118 {
119 	struct fan53555_device_info *di = rdev_get_drvdata(rdev);
120 
121 	switch (mode) {
122 	case REGULATOR_MODE_FAST:
123 		regmap_update_bits(di->regmap, di->vol_reg,
124 				VSEL_MODE, VSEL_MODE);
125 		break;
126 	case REGULATOR_MODE_NORMAL:
127 		regmap_update_bits(di->regmap, di->vol_reg, VSEL_MODE, 0);
128 		break;
129 	default:
130 		return -EINVAL;
131 	}
132 	return 0;
133 }
134 
135 static unsigned int fan53555_get_mode(struct regulator_dev *rdev)
136 {
137 	struct fan53555_device_info *di = rdev_get_drvdata(rdev);
138 	unsigned int val;
139 	int ret = 0;
140 
141 	ret = regmap_read(di->regmap, di->vol_reg, &val);
142 	if (ret < 0)
143 		return ret;
144 	if (val & VSEL_MODE)
145 		return REGULATOR_MODE_FAST;
146 	else
147 		return REGULATOR_MODE_NORMAL;
148 }
149 
150 static const int slew_rates[] = {
151 	64000,
152 	32000,
153 	16000,
154 	 8000,
155 	 4000,
156 	 2000,
157 	 1000,
158 	  500,
159 };
160 
161 static int fan53555_set_ramp(struct regulator_dev *rdev, int ramp)
162 {
163 	struct fan53555_device_info *di = rdev_get_drvdata(rdev);
164 	int regval = -1, i;
165 
166 	for (i = 0; i < ARRAY_SIZE(slew_rates); i++) {
167 		if (ramp <= slew_rates[i])
168 			regval = i;
169 		else
170 			break;
171 	}
172 
173 	if (regval < 0) {
174 		dev_err(di->dev, "unsupported ramp value %d\n", ramp);
175 		return -EINVAL;
176 	}
177 
178 	return regmap_update_bits(di->regmap, FAN53555_CONTROL,
179 				  CTL_SLEW_MASK, regval << CTL_SLEW_SHIFT);
180 }
181 
182 static struct regulator_ops fan53555_regulator_ops = {
183 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
184 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
185 	.set_voltage_time_sel = regulator_set_voltage_time_sel,
186 	.map_voltage = regulator_map_voltage_linear,
187 	.list_voltage = regulator_list_voltage_linear,
188 	.set_suspend_voltage = fan53555_set_suspend_voltage,
189 	.enable = regulator_enable_regmap,
190 	.disable = regulator_disable_regmap,
191 	.is_enabled = regulator_is_enabled_regmap,
192 	.set_mode = fan53555_set_mode,
193 	.get_mode = fan53555_get_mode,
194 	.set_ramp_delay = fan53555_set_ramp,
195 };
196 
197 static int fan53555_voltages_setup_fairchild(struct fan53555_device_info *di)
198 {
199 	/* Init voltage range and step */
200 	switch (di->chip_id) {
201 	case FAN53555_CHIP_ID_00:
202 	case FAN53555_CHIP_ID_01:
203 	case FAN53555_CHIP_ID_03:
204 	case FAN53555_CHIP_ID_05:
205 		di->vsel_min = 600000;
206 		di->vsel_step = 10000;
207 		break;
208 	case FAN53555_CHIP_ID_04:
209 		di->vsel_min = 603000;
210 		di->vsel_step = 12826;
211 		break;
212 	default:
213 		dev_err(di->dev,
214 			"Chip ID %d not supported!\n", di->chip_id);
215 		return -EINVAL;
216 	}
217 
218 	return 0;
219 }
220 
221 static int fan53555_voltages_setup_silergy(struct fan53555_device_info *di)
222 {
223 	/* Init voltage range and step */
224 	switch (di->chip_id) {
225 	case SILERGY_SYR82X:
226 		di->vsel_min = 712500;
227 		di->vsel_step = 12500;
228 		break;
229 	default:
230 		dev_err(di->dev,
231 			"Chip ID %d not supported!\n", di->chip_id);
232 		return -EINVAL;
233 	}
234 
235 	return 0;
236 }
237 
238 /* For 00,01,03,05 options:
239  * VOUT = 0.60V + NSELx * 10mV, from 0.60 to 1.23V.
240  * For 04 option:
241  * VOUT = 0.603V + NSELx * 12.826mV, from 0.603 to 1.411V.
242  * */
243 static int fan53555_device_setup(struct fan53555_device_info *di,
244 				struct fan53555_platform_data *pdata)
245 {
246 	int ret = 0;
247 
248 	/* Setup voltage control register */
249 	switch (pdata->sleep_vsel_id) {
250 	case FAN53555_VSEL_ID_0:
251 		di->sleep_reg = FAN53555_VSEL0;
252 		di->vol_reg = FAN53555_VSEL1;
253 		break;
254 	case FAN53555_VSEL_ID_1:
255 		di->sleep_reg = FAN53555_VSEL1;
256 		di->vol_reg = FAN53555_VSEL0;
257 		break;
258 	default:
259 		dev_err(di->dev, "Invalid VSEL ID!\n");
260 		return -EINVAL;
261 	}
262 
263 	switch (di->vendor) {
264 	case FAN53555_VENDOR_FAIRCHILD:
265 		ret = fan53555_voltages_setup_fairchild(di);
266 		break;
267 	case FAN53555_VENDOR_SILERGY:
268 		ret = fan53555_voltages_setup_silergy(di);
269 		break;
270 	default:
271 		dev_err(di->dev, "vendor %d not supported!\n", di->vendor);
272 		return -EINVAL;
273 	}
274 
275 	return ret;
276 }
277 
278 static int fan53555_regulator_register(struct fan53555_device_info *di,
279 			struct regulator_config *config)
280 {
281 	struct regulator_desc *rdesc = &di->desc;
282 
283 	rdesc->name = "fan53555-reg";
284 	rdesc->supply_name = "vin";
285 	rdesc->ops = &fan53555_regulator_ops;
286 	rdesc->type = REGULATOR_VOLTAGE;
287 	rdesc->n_voltages = FAN53555_NVOLTAGES;
288 	rdesc->enable_reg = di->vol_reg;
289 	rdesc->enable_mask = VSEL_BUCK_EN;
290 	rdesc->min_uV = di->vsel_min;
291 	rdesc->uV_step = di->vsel_step;
292 	rdesc->vsel_reg = di->vol_reg;
293 	rdesc->vsel_mask = VSEL_NSEL_MASK;
294 	rdesc->owner = THIS_MODULE;
295 
296 	di->rdev = devm_regulator_register(di->dev, &di->desc, config);
297 	return PTR_ERR_OR_ZERO(di->rdev);
298 }
299 
300 static const struct regmap_config fan53555_regmap_config = {
301 	.reg_bits = 8,
302 	.val_bits = 8,
303 };
304 
305 static struct fan53555_platform_data *fan53555_parse_dt(struct device *dev,
306 					      struct device_node *np,
307 					      const struct regulator_desc *desc)
308 {
309 	struct fan53555_platform_data *pdata;
310 	int ret;
311 	u32 tmp;
312 
313 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
314 	if (!pdata)
315 		return NULL;
316 
317 	pdata->regulator = of_get_regulator_init_data(dev, np, desc);
318 
319 	ret = of_property_read_u32(np, "fcs,suspend-voltage-selector",
320 				   &tmp);
321 	if (!ret)
322 		pdata->sleep_vsel_id = tmp;
323 
324 	return pdata;
325 }
326 
327 static const struct of_device_id fan53555_dt_ids[] = {
328 	{
329 		.compatible = "fcs,fan53555",
330 		.data = (void *)FAN53555_VENDOR_FAIRCHILD
331 	}, {
332 		.compatible = "silergy,syr827",
333 		.data = (void *)FAN53555_VENDOR_SILERGY,
334 	}, {
335 		.compatible = "silergy,syr828",
336 		.data = (void *)FAN53555_VENDOR_SILERGY,
337 	},
338 	{ }
339 };
340 MODULE_DEVICE_TABLE(of, fan53555_dt_ids);
341 
342 static int fan53555_regulator_probe(struct i2c_client *client,
343 				const struct i2c_device_id *id)
344 {
345 	struct device_node *np = client->dev.of_node;
346 	struct fan53555_device_info *di;
347 	struct fan53555_platform_data *pdata;
348 	struct regulator_config config = { };
349 	unsigned int val;
350 	int ret;
351 
352 	di = devm_kzalloc(&client->dev, sizeof(struct fan53555_device_info),
353 					GFP_KERNEL);
354 	if (!di)
355 		return -ENOMEM;
356 
357 	pdata = dev_get_platdata(&client->dev);
358 	if (!pdata)
359 		pdata = fan53555_parse_dt(&client->dev, np, &di->desc);
360 
361 	if (!pdata || !pdata->regulator) {
362 		dev_err(&client->dev, "Platform data not found!\n");
363 		return -ENODEV;
364 	}
365 
366 	di->regulator = pdata->regulator;
367 	if (client->dev.of_node) {
368 		const struct of_device_id *match;
369 
370 		match = of_match_device(of_match_ptr(fan53555_dt_ids),
371 					&client->dev);
372 		if (!match)
373 			return -ENODEV;
374 
375 		di->vendor = (unsigned long) match->data;
376 	} else {
377 		/* if no ramp constraint set, get the pdata ramp_delay */
378 		if (!di->regulator->constraints.ramp_delay) {
379 			int slew_idx = (pdata->slew_rate & 0x7)
380 						? pdata->slew_rate : 0;
381 
382 			di->regulator->constraints.ramp_delay
383 						= slew_rates[slew_idx];
384 		}
385 
386 		di->vendor = id->driver_data;
387 	}
388 
389 	di->regmap = devm_regmap_init_i2c(client, &fan53555_regmap_config);
390 	if (IS_ERR(di->regmap)) {
391 		dev_err(&client->dev, "Failed to allocate regmap!\n");
392 		return PTR_ERR(di->regmap);
393 	}
394 	di->dev = &client->dev;
395 	i2c_set_clientdata(client, di);
396 	/* Get chip ID */
397 	ret = regmap_read(di->regmap, FAN53555_ID1, &val);
398 	if (ret < 0) {
399 		dev_err(&client->dev, "Failed to get chip ID!\n");
400 		return ret;
401 	}
402 	di->chip_id = val & DIE_ID;
403 	/* Get chip revision */
404 	ret = regmap_read(di->regmap, FAN53555_ID2, &val);
405 	if (ret < 0) {
406 		dev_err(&client->dev, "Failed to get chip Rev!\n");
407 		return ret;
408 	}
409 	di->chip_rev = val & DIE_REV;
410 	dev_info(&client->dev, "FAN53555 Option[%d] Rev[%d] Detected!\n",
411 				di->chip_id, di->chip_rev);
412 	/* Device init */
413 	ret = fan53555_device_setup(di, pdata);
414 	if (ret < 0) {
415 		dev_err(&client->dev, "Failed to setup device!\n");
416 		return ret;
417 	}
418 	/* Register regulator */
419 	config.dev = di->dev;
420 	config.init_data = di->regulator;
421 	config.regmap = di->regmap;
422 	config.driver_data = di;
423 	config.of_node = np;
424 
425 	ret = fan53555_regulator_register(di, &config);
426 	if (ret < 0)
427 		dev_err(&client->dev, "Failed to register regulator!\n");
428 	return ret;
429 
430 }
431 
432 static const struct i2c_device_id fan53555_id[] = {
433 	{
434 		.name = "fan53555",
435 		.driver_data = FAN53555_VENDOR_FAIRCHILD
436 	}, {
437 		.name = "syr82x",
438 		.driver_data = FAN53555_VENDOR_SILERGY
439 	},
440 	{ },
441 };
442 MODULE_DEVICE_TABLE(i2c, fan53555_id);
443 
444 static struct i2c_driver fan53555_regulator_driver = {
445 	.driver = {
446 		.name = "fan53555-regulator",
447 		.of_match_table = of_match_ptr(fan53555_dt_ids),
448 	},
449 	.probe = fan53555_regulator_probe,
450 	.id_table = fan53555_id,
451 };
452 
453 module_i2c_driver(fan53555_regulator_driver);
454 
455 MODULE_AUTHOR("Yunfan Zhang <yfzhang@marvell.com>");
456 MODULE_DESCRIPTION("FAN53555 regulator driver");
457 MODULE_LICENSE("GPL v2");
458