1 /*
2 * Regulator driver for mp8865
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
11 * for more details.
12 */
13
14 #include <linux/i2c.h>
15 #include <linux/module.h>
16 #include <linux/of_device.h>
17 #include <linux/regmap.h>
18 #include <linux/regulator/driver.h>
19 #include <linux/regulator/of_regulator.h>
20
21 #define MP8865_MAX_VSEL 0x7f
22 #define VOL_MIN_IDX 0x00
23 #define VOL_MAX_IDX 0x7f
24 #define MP8865_ENABLE_TIME 150
25
26 /* Register definitions */
27 #define MP8865_VOUT_REG 0
28 #define MP8865_SYSCNTL_REG 1
29 #define MP8865_ID_REG 2
30 #define MP8865_STATUS_REG 3
31 #define MP8865_MAX_REG 4
32
33 #define MP8865_VOUT_MASK 0x7f
34 #define MP8865_VBOOT_MASK 0x80
35
36 #define MP8865_ENABLE 0x80
37 #define MP8865_GO_BIT 0x40
38 #define MP8865_SLEW_RATE_MASK 0x38
39 #define MP8865_SWITCH_FRE_MASK 0x06
40 #define MP8865_PFM_MODE 0X01
41
42 /* mp8865 chip information */
43 struct mp8865_chip {
44 struct device *dev;
45 struct regulator_desc desc;
46 struct regulator_dev *rdev;
47 struct regmap *regmap;
48 };
49
50 struct mp8865_platform_data {
51 struct regulator_init_data *mp8865_init_data;
52 struct device_node *of_node;
53 };
54
55 static const struct linear_range mp8865_voltage_ranges[] = {
56 REGULATOR_LINEAR_RANGE(600000, VOL_MIN_IDX, VOL_MAX_IDX, 10000),
57 };
58
mp8865_set_voltage(struct regulator_dev * rdev,unsigned sel)59 static int mp8865_set_voltage(struct regulator_dev *rdev, unsigned sel)
60 {
61 int ret;
62
63 ret = regmap_update_bits(rdev->regmap, MP8865_SYSCNTL_REG,
64 MP8865_GO_BIT, MP8865_GO_BIT);
65 if (ret)
66 return ret;
67
68 sel <<= ffs(rdev->desc->vsel_mask) - 1;
69 return regmap_write(rdev->regmap, MP8865_VOUT_REG, sel);
70 }
71
is_write_reg(struct device * dev,unsigned int reg)72 static bool is_write_reg(struct device *dev, unsigned int reg)
73 {
74 return (reg < MP8865_ID_REG) ? true : false;
75 }
76
is_volatile_reg(struct device * dev,unsigned int reg)77 static bool is_volatile_reg(struct device *dev, unsigned int reg)
78 {
79 return (reg == MP8865_STATUS_REG) ? true : false;
80 }
81
82 static const struct regmap_config mp8865_regmap_config = {
83 .reg_bits = 8,
84 .val_bits = 8,
85 .writeable_reg = is_write_reg,
86 .volatile_reg = is_volatile_reg,
87 .max_register = MP8865_MAX_REG,
88 .cache_type = REGCACHE_RBTREE,
89 };
90
91 static struct regulator_ops mp8865_dcdc_ops = {
92 .list_voltage = regulator_list_voltage_linear_range,
93 .map_voltage = regulator_map_voltage_linear_range,
94 .get_voltage_sel = regulator_get_voltage_sel_regmap,
95 .set_voltage_sel = mp8865_set_voltage,
96 .set_voltage_time_sel = regulator_set_voltage_time_sel,
97 .enable = regulator_enable_regmap,
98 .disable = regulator_disable_regmap,
99 .is_enabled = regulator_is_enabled_regmap,
100 };
101
102 static const struct of_device_id mp8865_of_match[] = {
103 {.compatible = "mps,mp8865", .data = (void *)0},
104 {},
105 };
106 MODULE_DEVICE_TABLE(of, mp8865_of_match);
107
108 static struct of_regulator_match mp8865_matches = {
109 .name = "mp8865_dcdc1",
110 .driver_data = (void *)0,
111 };
112
113 static struct mp8865_platform_data *
mp8865_parse_dt(struct i2c_client * client,struct of_regulator_match ** mp8865_reg_matches)114 mp8865_parse_dt(struct i2c_client *client,
115 struct of_regulator_match **mp8865_reg_matches)
116 {
117 struct mp8865_platform_data *pdata;
118 struct device_node *np, *regulators;
119 int ret;
120
121 pdata = devm_kzalloc(&client->dev, sizeof(struct mp8865_platform_data),
122 GFP_KERNEL);
123 if (!pdata)
124 return NULL;
125
126 np = of_node_get(client->dev.of_node);
127 regulators = of_find_node_by_name(np, "regulators");
128 if (!regulators) {
129 dev_err(&client->dev, "regulator node not found\n");
130 return NULL;
131 }
132
133 ret = of_regulator_match(&client->dev, regulators, &mp8865_matches, 1);
134 if (ret < 0) {
135 dev_err(&client->dev, "Error parsing regulators init data\n");
136 return NULL;
137 }
138 *mp8865_reg_matches = &mp8865_matches;
139 of_node_put(regulators);
140
141 pdata->mp8865_init_data = mp8865_matches.init_data;
142 pdata->of_node = mp8865_matches.of_node;
143
144 return pdata;
145 }
146
mp8865_probe(struct i2c_client * client,const struct i2c_device_id * id)147 static int mp8865_probe(struct i2c_client *client,
148 const struct i2c_device_id *id)
149 {
150 struct mp8865_chip *mp8865;
151 struct mp8865_platform_data *pdata;
152 struct of_regulator_match *mp8865_reg_matches = NULL;
153 struct regulator_dev *sy_rdev;
154 struct regulator_config config;
155 struct regulator_desc *rdesc;
156 int ret;
157
158 mp8865 = devm_kzalloc(&client->dev, sizeof(struct mp8865_chip),
159 GFP_KERNEL);
160 if (!mp8865)
161 return -ENOMEM;
162 pdata = dev_get_platdata(&client->dev);
163 if (!pdata)
164 pdata = mp8865_parse_dt(client, &mp8865_reg_matches);
165
166 if (!pdata || !pdata->mp8865_init_data) {
167 dev_err(&client->dev, "Platform data not found!\n");
168 return -ENODEV;
169 }
170
171 mp8865->dev = &client->dev;
172 mp8865->regmap = devm_regmap_init_i2c(client, &mp8865_regmap_config);
173 if (IS_ERR(mp8865->regmap)) {
174 dev_err(&client->dev, "Failed to allocate regmap!\n");
175 return PTR_ERR(mp8865->regmap);
176 }
177
178 i2c_set_clientdata(client, mp8865);
179
180 config.dev = mp8865->dev;
181 config.driver_data = mp8865;
182 config.init_data = pdata->mp8865_init_data;
183 config.of_node = pdata->of_node;
184 config.regmap = mp8865->regmap;
185
186 rdesc = &mp8865->desc;
187 rdesc->name = "mp8865_dcdc1",
188 rdesc->id = 0,
189 rdesc->ops = &mp8865_dcdc_ops,
190 rdesc->n_voltages = MP8865_MAX_VSEL + 1,
191 rdesc->linear_ranges = mp8865_voltage_ranges,
192 rdesc->n_linear_ranges = ARRAY_SIZE(mp8865_voltage_ranges),
193 rdesc->vsel_reg = MP8865_VOUT_REG;
194 rdesc->vsel_mask = MP8865_VOUT_MASK;
195 rdesc->enable_reg = MP8865_SYSCNTL_REG;
196 rdesc->enable_mask = MP8865_ENABLE;
197 rdesc->enable_time = MP8865_ENABLE_TIME;
198 rdesc->type = REGULATOR_VOLTAGE,
199 rdesc->owner = THIS_MODULE;
200
201 /* set slew_rate 16mV/uS */
202 ret = regmap_update_bits(mp8865->regmap, MP8865_SYSCNTL_REG,
203 MP8865_SLEW_RATE_MASK, 0x10);
204 if (ret) {
205 dev_err(mp8865->dev, "failed to set slew_rate\n");
206 return ret;
207 }
208
209 /* set switch_frequency 1.1MHz */
210 ret = regmap_update_bits(mp8865->regmap, MP8865_SYSCNTL_REG,
211 MP8865_SWITCH_FRE_MASK, 0x40);
212 if (ret) {
213 dev_err(mp8865->dev, "failed to set switch_frequency\n");
214 return ret;
215 }
216
217 sy_rdev = devm_regulator_register(mp8865->dev, &mp8865->desc,
218 &config);
219 if (IS_ERR(sy_rdev)) {
220 dev_err(mp8865->dev, "failed to register regulator\n");
221 return PTR_ERR(sy_rdev);
222 }
223
224 dev_info(mp8865->dev, "mp8865 register successful\n");
225
226 return 0;
227 }
228
229 static const struct i2c_device_id mp8865_id[] = {
230 { .name = "mps,mp8865", },
231 { },
232 };
233 MODULE_DEVICE_TABLE(i2c, mp8865_id);
234
235 static struct i2c_driver mp8865_driver = {
236 .driver = {
237 .name = "mp8865",
238 .of_match_table = of_match_ptr(mp8865_of_match),
239 .owner = THIS_MODULE,
240 },
241 .probe = mp8865_probe,
242 .id_table = mp8865_id,
243 };
244 module_i2c_driver(mp8865_driver);
245
246 MODULE_AUTHOR("Zain Wang <zain.wang@rock-chips.com>");
247 MODULE_DESCRIPTION("mp8865 voltage regulator driver");
248 MODULE_LICENSE("GPL v2");
249