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
tps51632_dcdc_set_ramp_delay(struct regulator_dev * rdev,int ramp_delay)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
tps51632_init_dcdc(struct tps51632_chip * tps,struct tps51632_regulator_platform_data * pdata)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
is_volatile_reg(struct device * dev,unsigned int reg)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
is_read_reg(struct device * dev,unsigned int reg)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
is_write_reg(struct device * dev,unsigned int reg)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_MAPLE,
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 *
of_get_tps51632_platform_data(struct device * dev,const struct regulator_desc * desc)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 *
of_get_tps51632_platform_data(struct device * dev,const struct regulator_desc * desc)242 of_get_tps51632_platform_data(struct device *dev,
243 const struct regulator_desc *desc)
244 {
245 return NULL;
246 }
247 #endif
248
tps51632_probe(struct i2c_client * client)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
tps51632_init(void)350 static int __init tps51632_init(void)
351 {
352 return i2c_add_driver(&tps51632_i2c_driver);
353 }
354 subsys_initcall(tps51632_init);
355
tps51632_cleanup(void)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