Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
[linux-block.git] / drivers / regulator / max8952.c
CommitLineData
1a59d1b8 1// SPDX-License-Identifier: GPL-2.0-or-later
202f4f53
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2/*
3 * max8952.c - Voltage and current regulation for the Maxim 8952
4 *
5 * Copyright (C) 2010 Samsung Electronics
6 * MyungJoo Ham <myungjoo.ham@samsung.com>
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7 */
8
9#include <linux/module.h>
10#include <linux/init.h>
11#include <linux/i2c.h>
12#include <linux/err.h>
13#include <linux/platform_device.h>
14#include <linux/regulator/driver.h>
15#include <linux/regulator/max8952.h>
d7a261c2 16#include <linux/gpio/consumer.h>
202f4f53 17#include <linux/io.h>
3ff4aa95 18#include <linux/of.h>
3ff4aa95 19#include <linux/regulator/of_regulator.h>
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20#include <linux/slab.h>
21
22/* Registers */
23enum {
24 MAX8952_REG_MODE0,
25 MAX8952_REG_MODE1,
26 MAX8952_REG_MODE2,
27 MAX8952_REG_MODE3,
28 MAX8952_REG_CONTROL,
29 MAX8952_REG_SYNC,
30 MAX8952_REG_RAMP,
31 MAX8952_REG_CHIP_ID1,
32 MAX8952_REG_CHIP_ID2,
33};
34
35struct max8952_data {
36 struct i2c_client *client;
202f4f53 37 struct max8952_platform_data *pdata;
fd742eaa
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38 struct gpio_desc *vid0_gpiod;
39 struct gpio_desc *vid1_gpiod;
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40 bool vid0;
41 bool vid1;
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42};
43
44static int max8952_read_reg(struct max8952_data *max8952, u8 reg)
45{
46 int ret = i2c_smbus_read_byte_data(max8952->client, reg);
a5f8f963 47
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48 if (ret > 0)
49 ret &= 0xff;
50
51 return ret;
52}
53
54static int max8952_write_reg(struct max8952_data *max8952,
55 u8 reg, u8 value)
56{
57 return i2c_smbus_write_byte_data(max8952->client, reg, value);
58}
59
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60static int max8952_list_voltage(struct regulator_dev *rdev,
61 unsigned int selector)
62{
63 struct max8952_data *max8952 = rdev_get_drvdata(rdev);
64
65 if (rdev_get_id(rdev) != 0)
66 return -EINVAL;
67
b9b49af5 68 return (max8952->pdata->dvs_mode[selector] * 10 + 770) * 1000;
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69}
70
b9b49af5 71static int max8952_get_voltage_sel(struct regulator_dev *rdev)
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72{
73 struct max8952_data *max8952 = rdev_get_drvdata(rdev);
74 u8 vid = 0;
75
76 if (max8952->vid0)
77 vid += 1;
78 if (max8952->vid1)
79 vid += 2;
80
b9b49af5 81 return vid;
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82}
83
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84static int max8952_set_voltage_sel(struct regulator_dev *rdev,
85 unsigned selector)
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86{
87 struct max8952_data *max8952 = rdev_get_drvdata(rdev);
202f4f53 88
fd742eaa 89 if (!max8952->vid0_gpiod || !max8952->vid1_gpiod) {
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90 /* DVS not supported */
91 return -EPERM;
92 }
93
6ea67d04
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94 max8952->vid0 = selector & 0x1;
95 max8952->vid1 = (selector >> 1) & 0x1;
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96 gpiod_set_value(max8952->vid0_gpiod, max8952->vid0);
97 gpiod_set_value(max8952->vid1_gpiod, max8952->vid1);
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98
99 return 0;
100}
101
6e09f4af 102static const struct regulator_ops max8952_ops = {
202f4f53 103 .list_voltage = max8952_list_voltage,
b9b49af5 104 .get_voltage_sel = max8952_get_voltage_sel,
6ea67d04 105 .set_voltage_sel = max8952_set_voltage_sel,
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106};
107
bd6ff0d6 108static const struct regulator_desc regulator = {
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109 .name = "MAX8952_VOUT",
110 .id = 0,
111 .n_voltages = MAX8952_NUM_DVS_MODE,
112 .ops = &max8952_ops,
113 .type = REGULATOR_VOLTAGE,
114 .owner = THIS_MODULE,
115};
116
3ff4aa95 117#ifdef CONFIG_OF
cfe6e333 118static const struct of_device_id max8952_dt_match[] = {
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119 { .compatible = "maxim,max8952" },
120 {},
121};
122MODULE_DEVICE_TABLE(of, max8952_dt_match);
123
124static struct max8952_platform_data *max8952_parse_dt(struct device *dev)
125{
126 struct max8952_platform_data *pd;
127 struct device_node *np = dev->of_node;
128 int ret;
129 int i;
130
131 pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
7752d964 132 if (!pd)
3ff4aa95 133 return NULL;
3ff4aa95 134
3ff4aa95
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135 if (of_property_read_u32(np, "max8952,default-mode", &pd->default_mode))
136 dev_warn(dev, "Default mode not specified, assuming 0\n");
137
138 ret = of_property_read_u32_array(np, "max8952,dvs-mode-microvolt",
139 pd->dvs_mode, ARRAY_SIZE(pd->dvs_mode));
140 if (ret) {
141 dev_err(dev, "max8952,dvs-mode-microvolt property not specified");
142 return NULL;
143 }
144
145 for (i = 0; i < ARRAY_SIZE(pd->dvs_mode); ++i) {
146 if (pd->dvs_mode[i] < 770000 || pd->dvs_mode[i] > 1400000) {
147 dev_err(dev, "DVS voltage %d out of range\n", i);
148 return NULL;
149 }
150 pd->dvs_mode[i] = (pd->dvs_mode[i] - 770000) / 10000;
151 }
152
153 if (of_property_read_u32(np, "max8952,sync-freq", &pd->sync_freq))
154 dev_warn(dev, "max8952,sync-freq property not specified, defaulting to 26MHz\n");
155
156 if (of_property_read_u32(np, "max8952,ramp-speed", &pd->ramp_speed))
157 dev_warn(dev, "max8952,ramp-speed property not specified, defaulting to 32mV/us\n");
158
072e78b1 159 pd->reg_data = of_get_regulator_init_data(dev, np, &regulator);
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160 if (!pd->reg_data) {
161 dev_err(dev, "Failed to parse regulator init data\n");
162 return NULL;
163 }
164
165 return pd;
166}
167#else
168static struct max8952_platform_data *max8952_parse_dt(struct device *dev)
169{
170 return NULL;
171}
172#endif
173
c20c3673 174static int max8952_pmic_probe(struct i2c_client *client)
202f4f53 175{
6b96092a 176 struct i2c_adapter *adapter = client->adapter;
dff91d0b 177 struct max8952_platform_data *pdata = dev_get_platdata(&client->dev);
c172708d 178 struct regulator_config config = { };
202f4f53 179 struct max8952_data *max8952;
b874f41c 180 struct regulator_dev *rdev;
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181 struct gpio_desc *gpiod;
182 enum gpiod_flags gflags;
202f4f53 183
fd742eaa 184 int ret = 0;
202f4f53 185
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186 if (client->dev.of_node)
187 pdata = max8952_parse_dt(&client->dev);
188
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189 if (!pdata) {
190 dev_err(&client->dev, "Require the platform data\n");
191 return -EINVAL;
192 }
193
194 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
195 return -EIO;
196
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197 max8952 = devm_kzalloc(&client->dev, sizeof(struct max8952_data),
198 GFP_KERNEL);
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199 if (!max8952)
200 return -ENOMEM;
201
202 max8952->client = client;
202f4f53 203 max8952->pdata = pdata;
202f4f53 204
b874f41c 205 config.dev = &client->dev;
3ec6eb9c 206 config.init_data = pdata->reg_data;
c172708d 207 config.driver_data = max8952;
71622e15 208 config.of_node = client->dev.of_node;
c172708d 209
3ec6eb9c 210 if (pdata->reg_data->constraints.boot_on)
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211 gflags = GPIOD_OUT_HIGH;
212 else
213 gflags = GPIOD_OUT_LOW;
63239e4b 214 gflags |= GPIOD_FLAGS_BIT_NONEXCLUSIVE;
894077d5
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215 /*
216 * Do not use devm* here: the regulator core takes over the
217 * lifecycle management of the GPIO descriptor.
218 */
219 gpiod = gpiod_get_optional(&client->dev,
220 "max8952,en",
221 gflags);
d7a261c2
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222 if (IS_ERR(gpiod))
223 return PTR_ERR(gpiod);
224 if (gpiod)
225 config.ena_gpiod = gpiod;
b669e0ad 226
b874f41c 227 rdev = devm_regulator_register(&client->dev, &regulator, &config);
b874f41c
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228 if (IS_ERR(rdev)) {
229 ret = PTR_ERR(rdev);
230 dev_err(&client->dev, "regulator init failed (%d)\n", ret);
372de4aa 231 return ret;
da05738e 232 }
202f4f53 233
c8237f01
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234 max8952->vid0 = pdata->default_mode & 0x1;
235 max8952->vid1 = (pdata->default_mode >> 1) & 0x1;
202f4f53 236
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237 /* Fetch vid0 and vid1 GPIOs if available */
238 gflags = max8952->vid0 ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
239 max8952->vid0_gpiod = devm_gpiod_get_index_optional(&client->dev,
240 "max8952,vid",
241 0, gflags);
242 if (IS_ERR(max8952->vid0_gpiod))
243 return PTR_ERR(max8952->vid0_gpiod);
244 gflags = max8952->vid1 ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
245 max8952->vid1_gpiod = devm_gpiod_get_index_optional(&client->dev,
246 "max8952,vid",
247 1, gflags);
248 if (IS_ERR(max8952->vid1_gpiod))
249 return PTR_ERR(max8952->vid1_gpiod);
250
251 /* If either VID GPIO is missing just disable this */
252 if (!max8952->vid0_gpiod || !max8952->vid1_gpiod) {
b874f41c 253 dev_warn(&client->dev, "VID0/1 gpio invalid: "
fd742eaa 254 "DVS not available.\n");
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255 max8952->vid0 = 0;
256 max8952->vid1 = 0;
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257 /* Make sure if we have any descriptors they get set to low */
258 if (max8952->vid0_gpiod)
259 gpiod_set_value(max8952->vid0_gpiod, 0);
260 if (max8952->vid1_gpiod)
261 gpiod_set_value(max8952->vid1_gpiod, 0);
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262
263 /* Disable Pulldown of EN only */
264 max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x60);
265
b874f41c 266 dev_err(&client->dev, "DVS modes disabled because VID0 and VID1"
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267 " do not have proper controls.\n");
268 } else {
269 /*
270 * Disable Pulldown on EN, VID0, VID1 to reduce
271 * leakage current of MAX8952 assuming that MAX8952
272 * is turned on (EN==1). Note that without having VID0/1
273 * properly connected, turning pulldown off can be
274 * problematic. Thus, turn this off only when they are
275 * controllable by GPIO.
276 */
277 max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x0);
278 }
279
280 max8952_write_reg(max8952, MAX8952_REG_MODE0,
281 (max8952_read_reg(max8952,
282 MAX8952_REG_MODE0) & 0xC0) |
283 (pdata->dvs_mode[0] & 0x3F));
284 max8952_write_reg(max8952, MAX8952_REG_MODE1,
285 (max8952_read_reg(max8952,
286 MAX8952_REG_MODE1) & 0xC0) |
287 (pdata->dvs_mode[1] & 0x3F));
288 max8952_write_reg(max8952, MAX8952_REG_MODE2,
289 (max8952_read_reg(max8952,
290 MAX8952_REG_MODE2) & 0xC0) |
291 (pdata->dvs_mode[2] & 0x3F));
292 max8952_write_reg(max8952, MAX8952_REG_MODE3,
293 (max8952_read_reg(max8952,
294 MAX8952_REG_MODE3) & 0xC0) |
295 (pdata->dvs_mode[3] & 0x3F));
296
297 max8952_write_reg(max8952, MAX8952_REG_SYNC,
298 (max8952_read_reg(max8952, MAX8952_REG_SYNC) & 0x3F) |
299 ((pdata->sync_freq & 0x3) << 6));
300 max8952_write_reg(max8952, MAX8952_REG_RAMP,
301 (max8952_read_reg(max8952, MAX8952_REG_RAMP) & 0x1F) |
302 ((pdata->ramp_speed & 0x7) << 5));
303
304 i2c_set_clientdata(client, max8952);
305
da05738e 306 return 0;
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307}
308
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309static const struct i2c_device_id max8952_ids[] = {
310 { "max8952", 0 },
311 { },
312};
313MODULE_DEVICE_TABLE(i2c, max8952_ids);
314
315static struct i2c_driver max8952_pmic_driver = {
c20c3673 316 .probe_new = max8952_pmic_probe,
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317 .driver = {
318 .name = "max8952",
3ff4aa95 319 .of_match_table = of_match_ptr(max8952_dt_match),
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320 },
321 .id_table = max8952_ids,
322};
323
324static int __init max8952_pmic_init(void)
325{
326 return i2c_add_driver(&max8952_pmic_driver);
327}
328subsys_initcall(max8952_pmic_init);
329
330static void __exit max8952_pmic_exit(void)
331{
332 i2c_del_driver(&max8952_pmic_driver);
333}
334module_exit(max8952_pmic_exit);
335
336MODULE_DESCRIPTION("MAXIM 8952 voltage regulator driver");
337MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
338MODULE_LICENSE("GPL");