xref: /linux/drivers/regulator/tps51632-regulator.c (revision 7a92fc8b4d20680e4c20289a670d8fca2d1f2c1b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * tps51632-regulator.c -- TI TPS51632
4  *
5  * Regulator driver for TPS51632 3-2-1 Phase D-Cap Step Down Driverless
6  * Controller with serial VID control and DVFS.
7  *
8  * Copyright (c) 2012, NVIDIA Corporation.
9  *
10  * Author: Laxman Dewangan <ldewangan@nvidia.com>
11  */
12 
13 #include <linux/err.h>
14 #include <linux/i2c.h>
15 #include <linux/init.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/platform_device.h>
20 #include <linux/regmap.h>
21 #include <linux/regulator/driver.h>
22 #include <linux/regulator/machine.h>
23 #include <linux/regulator/of_regulator.h>
24 #include <linux/regulator/tps51632-regulator.h>
25 #include <linux/slab.h>
26 
27 /* Register definitions */
28 #define TPS51632_VOLTAGE_SELECT_REG		0x0
29 #define TPS51632_VOLTAGE_BASE_REG		0x1
30 #define TPS51632_OFFSET_REG			0x2
31 #define TPS51632_IMON_REG			0x3
32 #define TPS51632_VMAX_REG			0x4
33 #define TPS51632_DVFS_CONTROL_REG		0x5
34 #define TPS51632_POWER_STATE_REG		0x6
35 #define TPS51632_SLEW_REGS			0x7
36 #define TPS51632_FAULT_REG			0x14
37 
38 #define TPS51632_MAX_REG			0x15
39 
40 #define TPS51632_VOUT_MASK			0x7F
41 #define TPS51632_VOUT_OFFSET_MASK		0x1F
42 #define TPS51632_VMAX_MASK			0x7F
43 #define TPS51632_VMAX_LOCK			0x80
44 
45 /* TPS51632_DVFS_CONTROL_REG */
46 #define TPS51632_DVFS_PWMEN			0x1
47 #define TPS51632_DVFS_STEP_20			0x2
48 #define TPS51632_DVFS_VMAX_PG			0x4
49 #define TPS51632_DVFS_PWMRST			0x8
50 #define TPS51632_DVFS_OCA_EN			0x10
51 #define TPS51632_DVFS_FCCM			0x20
52 
53 /* TPS51632_POWER_STATE_REG */
54 #define TPS51632_POWER_STATE_MASK		0x03
55 #define TPS51632_POWER_STATE_MULTI_PHASE_CCM	0x0
56 #define TPS51632_POWER_STATE_SINGLE_PHASE_CCM	0x1
57 #define TPS51632_POWER_STATE_SINGLE_PHASE_DCM	0x2
58 
59 #define TPS51632_MIN_VOLTAGE			500000
60 #define TPS51632_MAX_VOLTAGE			1520000
61 #define TPS51632_VOLTAGE_STEP_10mV		10000
62 #define TPS51632_VOLTAGE_STEP_20mV		20000
63 #define TPS51632_MAX_VSEL			0x7F
64 #define TPS51632_MIN_VSEL			0x19
65 #define TPS51632_DEFAULT_RAMP_DELAY		6000
66 #define TPS51632_VOLT_VSEL(uV)					\
67 		(DIV_ROUND_UP(uV - TPS51632_MIN_VOLTAGE,	\
68 			TPS51632_VOLTAGE_STEP_10mV) +		\
69 			TPS51632_MIN_VSEL)
70 
71 /* TPS51632 chip information */
72 struct tps51632_chip {
73 	struct device *dev;
74 	struct regulator_desc desc;
75 	struct regulator_dev *rdev;
76 	struct regmap *regmap;
77 };
78 
79 static int tps51632_dcdc_set_ramp_delay(struct regulator_dev *rdev,
80 		int ramp_delay)
81 {
82 	struct tps51632_chip *tps = rdev_get_drvdata(rdev);
83 	int bit;
84 	int ret;
85 
86 	if (ramp_delay == 0)
87 		bit = 0;
88 	else
89 		bit = DIV_ROUND_UP(ramp_delay, 6000) - 1;
90 
91 	ret = regmap_write(tps->regmap, TPS51632_SLEW_REGS, BIT(bit));
92 	if (ret < 0)
93 		dev_err(tps->dev, "SLEW reg write failed, err %d\n", ret);
94 	return ret;
95 }
96 
97 static const struct regulator_ops tps51632_dcdc_ops = {
98 	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
99 	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
100 	.list_voltage		= regulator_list_voltage_linear,
101 	.set_voltage_time_sel	= regulator_set_voltage_time_sel,
102 	.set_ramp_delay		= tps51632_dcdc_set_ramp_delay,
103 };
104 
105 static int tps51632_init_dcdc(struct tps51632_chip *tps,
106 		struct tps51632_regulator_platform_data *pdata)
107 {
108 	int ret;
109 	uint8_t	control = 0;
110 	int vsel;
111 
112 	if (!pdata->enable_pwm_dvfs)
113 		goto skip_pwm_config;
114 
115 	control |= TPS51632_DVFS_PWMEN;
116 	vsel = TPS51632_VOLT_VSEL(pdata->base_voltage_uV);
117 	ret = regmap_write(tps->regmap, TPS51632_VOLTAGE_BASE_REG, vsel);
118 	if (ret < 0) {
119 		dev_err(tps->dev, "BASE reg write failed, err %d\n", ret);
120 		return ret;
121 	}
122 
123 	if (pdata->dvfs_step_20mV)
124 		control |= TPS51632_DVFS_STEP_20;
125 
126 	if (pdata->max_voltage_uV) {
127 		unsigned int vmax;
128 		/**
129 		 * TPS51632 hw behavior: VMAX register can be write only
130 		 * once as it get locked after first write. The lock get
131 		 * reset only when device is power-reset.
132 		 * Write register only when lock bit is not enabled.
133 		 */
134 		ret = regmap_read(tps->regmap, TPS51632_VMAX_REG, &vmax);
135 		if (ret < 0) {
136 			dev_err(tps->dev, "VMAX read failed, err %d\n", ret);
137 			return ret;
138 		}
139 		if (!(vmax & TPS51632_VMAX_LOCK)) {
140 			vsel = TPS51632_VOLT_VSEL(pdata->max_voltage_uV);
141 			ret = regmap_write(tps->regmap, TPS51632_VMAX_REG,
142 					vsel);
143 			if (ret < 0) {
144 				dev_err(tps->dev,
145 					"VMAX write failed, err %d\n", ret);
146 				return ret;
147 			}
148 		}
149 	}
150 
151 skip_pwm_config:
152 	ret = regmap_write(tps->regmap, TPS51632_DVFS_CONTROL_REG, control);
153 	if (ret < 0)
154 		dev_err(tps->dev, "DVFS reg write failed, err %d\n", ret);
155 	return ret;
156 }
157 
158 static bool is_volatile_reg(struct device *dev, unsigned int reg)
159 {
160 	switch (reg) {
161 	case TPS51632_OFFSET_REG:
162 	case TPS51632_FAULT_REG:
163 	case TPS51632_IMON_REG:
164 		return true;
165 	default:
166 		return false;
167 	}
168 }
169 
170 static bool is_read_reg(struct device *dev, unsigned int reg)
171 {
172 	switch (reg) {
173 	case 0x08 ... 0x0F:
174 		return false;
175 	default:
176 		return true;
177 	}
178 }
179 
180 static bool is_write_reg(struct device *dev, unsigned int reg)
181 {
182 	switch (reg) {
183 	case TPS51632_VOLTAGE_SELECT_REG:
184 	case TPS51632_VOLTAGE_BASE_REG:
185 	case TPS51632_VMAX_REG:
186 	case TPS51632_DVFS_CONTROL_REG:
187 	case TPS51632_POWER_STATE_REG:
188 	case TPS51632_SLEW_REGS:
189 		return true;
190 	default:
191 		return false;
192 	}
193 }
194 
195 static const struct regmap_config tps51632_regmap_config = {
196 	.reg_bits		= 8,
197 	.val_bits		= 8,
198 	.writeable_reg		= is_write_reg,
199 	.readable_reg		= is_read_reg,
200 	.volatile_reg		= is_volatile_reg,
201 	.max_register		= TPS51632_MAX_REG - 1,
202 	.cache_type		= REGCACHE_RBTREE,
203 };
204 
205 #if defined(CONFIG_OF)
206 static const struct of_device_id tps51632_of_match[] = {
207 	{ .compatible = "ti,tps51632",},
208 	{},
209 };
210 MODULE_DEVICE_TABLE(of, tps51632_of_match);
211 
212 static struct tps51632_regulator_platform_data *
213 	of_get_tps51632_platform_data(struct device *dev,
214 				      const struct regulator_desc *desc)
215 {
216 	struct tps51632_regulator_platform_data *pdata;
217 	struct device_node *np = dev->of_node;
218 
219 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
220 	if (!pdata)
221 		return NULL;
222 
223 	pdata->reg_init_data = of_get_regulator_init_data(dev, dev->of_node,
224 							  desc);
225 	if (!pdata->reg_init_data) {
226 		dev_err(dev, "Not able to get OF regulator init data\n");
227 		return NULL;
228 	}
229 
230 	pdata->enable_pwm_dvfs =
231 			of_property_read_bool(np, "ti,enable-pwm-dvfs");
232 	pdata->dvfs_step_20mV = of_property_read_bool(np, "ti,dvfs-step-20mV");
233 
234 	pdata->base_voltage_uV = pdata->reg_init_data->constraints.min_uV ? :
235 					TPS51632_MIN_VOLTAGE;
236 	pdata->max_voltage_uV = pdata->reg_init_data->constraints.max_uV ? :
237 					TPS51632_MAX_VOLTAGE;
238 	return pdata;
239 }
240 #else
241 static struct tps51632_regulator_platform_data *
242 	of_get_tps51632_platform_data(struct device *dev,
243 				      const struct regulator_desc *desc)
244 {
245 	return NULL;
246 }
247 #endif
248 
249 static int tps51632_probe(struct i2c_client *client)
250 {
251 	struct tps51632_regulator_platform_data *pdata;
252 	struct regulator_dev *rdev;
253 	struct tps51632_chip *tps;
254 	int ret;
255 	struct regulator_config config = { };
256 
257 	tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL);
258 	if (!tps)
259 		return -ENOMEM;
260 
261 	tps->dev = &client->dev;
262 	tps->desc.name = client->name;
263 	tps->desc.id = 0;
264 	tps->desc.ramp_delay = TPS51632_DEFAULT_RAMP_DELAY;
265 	tps->desc.min_uV = TPS51632_MIN_VOLTAGE;
266 	tps->desc.uV_step = TPS51632_VOLTAGE_STEP_10mV;
267 	tps->desc.linear_min_sel = TPS51632_MIN_VSEL;
268 	tps->desc.n_voltages = TPS51632_MAX_VSEL + 1;
269 	tps->desc.ops = &tps51632_dcdc_ops;
270 	tps->desc.type = REGULATOR_VOLTAGE;
271 	tps->desc.owner = THIS_MODULE;
272 
273 	pdata = dev_get_platdata(&client->dev);
274 	if (!pdata && client->dev.of_node)
275 		pdata = of_get_tps51632_platform_data(&client->dev, &tps->desc);
276 	if (!pdata) {
277 		dev_err(&client->dev, "No Platform data\n");
278 		return -EINVAL;
279 	}
280 
281 	if (pdata->enable_pwm_dvfs) {
282 		if ((pdata->base_voltage_uV < TPS51632_MIN_VOLTAGE) ||
283 		    (pdata->base_voltage_uV > TPS51632_MAX_VOLTAGE)) {
284 			dev_err(&client->dev, "Invalid base_voltage_uV setting\n");
285 			return -EINVAL;
286 		}
287 
288 		if ((pdata->max_voltage_uV) &&
289 		    ((pdata->max_voltage_uV < TPS51632_MIN_VOLTAGE) ||
290 		     (pdata->max_voltage_uV > TPS51632_MAX_VOLTAGE))) {
291 			dev_err(&client->dev, "Invalid max_voltage_uV setting\n");
292 			return -EINVAL;
293 		}
294 	}
295 
296 	if (pdata->enable_pwm_dvfs)
297 		tps->desc.vsel_reg = TPS51632_VOLTAGE_BASE_REG;
298 	else
299 		tps->desc.vsel_reg = TPS51632_VOLTAGE_SELECT_REG;
300 	tps->desc.vsel_mask = TPS51632_VOUT_MASK;
301 
302 	tps->regmap = devm_regmap_init_i2c(client, &tps51632_regmap_config);
303 	if (IS_ERR(tps->regmap)) {
304 		ret = PTR_ERR(tps->regmap);
305 		dev_err(&client->dev, "regmap init failed, err %d\n", ret);
306 		return ret;
307 	}
308 	i2c_set_clientdata(client, tps);
309 
310 	ret = tps51632_init_dcdc(tps, pdata);
311 	if (ret < 0) {
312 		dev_err(tps->dev, "Init failed, err = %d\n", ret);
313 		return ret;
314 	}
315 
316 	/* Register the regulators */
317 	config.dev = &client->dev;
318 	config.init_data = pdata->reg_init_data;
319 	config.driver_data = tps;
320 	config.regmap = tps->regmap;
321 	config.of_node = client->dev.of_node;
322 
323 	rdev = devm_regulator_register(&client->dev, &tps->desc, &config);
324 	if (IS_ERR(rdev)) {
325 		dev_err(tps->dev, "regulator register failed\n");
326 		return PTR_ERR(rdev);
327 	}
328 
329 	tps->rdev = rdev;
330 	return 0;
331 }
332 
333 static const struct i2c_device_id tps51632_id[] = {
334 	{.name = "tps51632",},
335 	{},
336 };
337 
338 MODULE_DEVICE_TABLE(i2c, tps51632_id);
339 
340 static struct i2c_driver tps51632_i2c_driver = {
341 	.driver = {
342 		.name = "tps51632",
343 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
344 		.of_match_table = of_match_ptr(tps51632_of_match),
345 	},
346 	.probe = tps51632_probe,
347 	.id_table = tps51632_id,
348 };
349 
350 static int __init tps51632_init(void)
351 {
352 	return i2c_add_driver(&tps51632_i2c_driver);
353 }
354 subsys_initcall(tps51632_init);
355 
356 static void __exit tps51632_cleanup(void)
357 {
358 	i2c_del_driver(&tps51632_i2c_driver);
359 }
360 module_exit(tps51632_cleanup);
361 
362 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
363 MODULE_DESCRIPTION("TPS51632 voltage regulator driver");
364 MODULE_LICENSE("GPL v2");
365