1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
|
// SPDX-License-Identifier: GPL-2.0-or-later
//
// max20086-regulator.c - MAX20086-MAX20089 camera power protector driver
//
// Copyright (C) 2022 Laurent Pinchart <laurent.pinchart@idesonboard.com>
// Copyright (C) 2018 Avnet, Inc.
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include <linux/slab.h>
/* Register Offset */
#define MAX20086_REG_MASK 0x00
#define MAX20086_REG_CONFIG 0x01
#define MAX20086_REG_ID 0x02
#define MAX20086_REG_STAT1 0x03
#define MAX20086_REG_STAT2_L 0x04
#define MAX20086_REG_STAT2_H 0x05
#define MAX20086_REG_ADC1 0x06
#define MAX20086_REG_ADC2 0x07
#define MAX20086_REG_ADC3 0x08
#define MAX20086_REG_ADC4 0x09
/* DEVICE IDs */
#define MAX20086_DEVICE_ID_MAX20086 0x40
#define MAX20086_DEVICE_ID_MAX20087 0x20
#define MAX20086_DEVICE_ID_MAX20088 0x10
#define MAX20086_DEVICE_ID_MAX20089 0x00
#define DEVICE_ID_MASK 0xf0
/* Register bits */
#define MAX20086_EN_MASK 0x0f
#define MAX20086_EN_OUT1 0x01
#define MAX20086_EN_OUT2 0x02
#define MAX20086_EN_OUT3 0x04
#define MAX20086_EN_OUT4 0x08
#define MAX20086_INT_DISABLE_ALL 0x3f
#define MAX20086_MAX_REGULATORS 4
struct max20086_chip_info {
u8 id;
unsigned int num_outputs;
};
struct max20086_regulator {
struct device_node *of_node;
struct regulator_init_data *init_data;
const struct regulator_desc *desc;
struct regulator_dev *rdev;
};
struct max20086 {
struct device *dev;
struct regmap *regmap;
struct gpio_desc *ena_gpiod;
const struct max20086_chip_info *info;
struct max20086_regulator regulators[MAX20086_MAX_REGULATORS];
};
static const struct regulator_ops max20086_buck_ops = {
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
.is_enabled = regulator_is_enabled_regmap,
};
#define MAX20086_REGULATOR_DESC(n) \
{ \
.name = "OUT"#n, \
.supply_name = "in", \
.id = (n) - 1, \
.ops = &max20086_buck_ops, \
.type = REGULATOR_VOLTAGE, \
.owner = THIS_MODULE, \
.enable_reg = MAX20086_REG_CONFIG, \
.enable_mask = 1 << ((n) - 1), \
.enable_val = 1 << ((n) - 1), \
.disable_val = 0, \
}
static const char * const max20086_output_names[] = {
"OUT1",
"OUT2",
"OUT3",
"OUT4",
};
static const struct regulator_desc max20086_regulators[] = {
MAX20086_REGULATOR_DESC(1),
MAX20086_REGULATOR_DESC(2),
MAX20086_REGULATOR_DESC(3),
MAX20086_REGULATOR_DESC(4),
};
static int max20086_regulators_register(struct max20086 *chip)
{
unsigned int i;
for (i = 0; i < chip->info->num_outputs; i++) {
struct max20086_regulator *reg = &chip->regulators[i];
struct regulator_config config = { };
struct regulator_dev *rdev;
config.dev = chip->dev;
config.init_data = reg->init_data;
config.driver_data = chip;
config.of_node = reg->of_node;
config.regmap = chip->regmap;
config.ena_gpiod = chip->ena_gpiod;
rdev = devm_regulator_register(chip->dev, reg->desc, &config);
if (IS_ERR(rdev)) {
dev_err(chip->dev,
"Failed to register regulator output %s\n",
reg->desc->name);
return PTR_ERR(rdev);
}
reg->rdev = rdev;
}
return 0;
}
static int max20086_parse_regulators_dt(struct max20086 *chip, bool *boot_on)
{
struct of_regulator_match matches[MAX20086_MAX_REGULATORS] = { };
struct device_node *node;
unsigned int i;
int ret;
node = of_get_child_by_name(chip->dev->of_node, "regulators");
if (!node) {
dev_err(chip->dev, "regulators node not found\n");
return -ENODEV;
}
for (i = 0; i < chip->info->num_outputs; ++i)
matches[i].name = max20086_output_names[i];
ret = of_regulator_match(chip->dev, node, matches,
chip->info->num_outputs);
of_node_put(node);
if (ret < 0) {
dev_err(chip->dev, "Failed to match regulators\n");
return -EINVAL;
}
*boot_on = false;
for (i = 0; i < chip->info->num_outputs; i++) {
struct max20086_regulator *reg = &chip->regulators[i];
reg->init_data = matches[i].init_data;
reg->of_node = matches[i].of_node;
reg->desc = &max20086_regulators[i];
if (reg->init_data) {
if (reg->init_data->constraints.always_on ||
reg->init_data->constraints.boot_on)
*boot_on = true;
}
}
return 0;
}
static int max20086_detect(struct max20086 *chip)
{
unsigned int data;
int ret;
ret = regmap_read(chip->regmap, MAX20086_REG_ID, &data);
if (ret < 0) {
dev_err(chip->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
return ret;
}
if ((data & DEVICE_ID_MASK) != chip->info->id) {
dev_err(chip->dev, "Invalid device ID 0x%02x\n", data);
return -ENXIO;
}
return 0;
}
static bool max20086_gen_is_writeable_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
case MAX20086_REG_MASK:
case MAX20086_REG_CONFIG:
return true;
default:
return false;
}
}
static const struct regmap_config max20086_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.writeable_reg = max20086_gen_is_writeable_reg,
.max_register = 0x9,
.cache_type = REGCACHE_NONE,
};
static int max20086_i2c_probe(struct i2c_client *i2c)
{
struct max20086 *chip;
enum gpiod_flags flags;
bool boot_on;
int ret;
chip = devm_kzalloc(&i2c->dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
chip->dev = &i2c->dev;
chip->info = device_get_match_data(chip->dev);
i2c_set_clientdata(i2c, chip);
chip->regmap = devm_regmap_init_i2c(i2c, &max20086_regmap_config);
if (IS_ERR(chip->regmap)) {
ret = PTR_ERR(chip->regmap);
dev_err(chip->dev, "Failed to allocate register map: %d\n", ret);
return ret;
}
ret = max20086_parse_regulators_dt(chip, &boot_on);
if (ret < 0)
return ret;
ret = max20086_detect(chip);
if (ret < 0)
return ret;
/* Until IRQ support is added, just disable all interrupts. */
ret = regmap_update_bits(chip->regmap, MAX20086_REG_MASK,
MAX20086_INT_DISABLE_ALL,
MAX20086_INT_DISABLE_ALL);
if (ret < 0) {
dev_err(chip->dev, "Failed to disable interrupts: %d\n", ret);
return ret;
}
/*
* Get the enable GPIO. If any of the outputs is marked as being
* enabled at boot, request the GPIO with an initial high state to
* avoid disabling outputs that may have been turned on by the boot
* loader. Otherwise, request it with a low state to enter lower-power
* shutdown.
*/
flags = boot_on ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
chip->ena_gpiod = devm_gpiod_get(chip->dev, "enable", flags);
if (IS_ERR(chip->ena_gpiod)) {
ret = PTR_ERR(chip->ena_gpiod);
dev_err(chip->dev, "Failed to get enable GPIO: %d\n", ret);
return ret;
}
ret = max20086_regulators_register(chip);
if (ret < 0) {
dev_err(chip->dev, "Failed to register regulators: %d\n", ret);
return ret;
}
return 0;
}
static const struct i2c_device_id max20086_i2c_id[] = {
{ "max20086" },
{ "max20087" },
{ "max20088" },
{ "max20089" },
{ /* Sentinel */ },
};
MODULE_DEVICE_TABLE(i2c, max20086_i2c_id);
static const struct of_device_id max20086_dt_ids[] __maybe_unused = {
{
.compatible = "maxim,max20086",
.data = &(const struct max20086_chip_info) {
.id = MAX20086_DEVICE_ID_MAX20086,
.num_outputs = 4,
}
}, {
.compatible = "maxim,max20087",
.data = &(const struct max20086_chip_info) {
.id = MAX20086_DEVICE_ID_MAX20087,
.num_outputs = 4,
}
}, {
.compatible = "maxim,max20088",
.data = &(const struct max20086_chip_info) {
.id = MAX20086_DEVICE_ID_MAX20088,
.num_outputs = 2,
}
}, {
.compatible = "maxim,max20089",
.data = &(const struct max20086_chip_info) {
.id = MAX20086_DEVICE_ID_MAX20089,
.num_outputs = 2,
}
},
{ /* Sentinel */ },
};
MODULE_DEVICE_TABLE(of, max20086_dt_ids);
static struct i2c_driver max20086_regulator_driver = {
.driver = {
.name = "max20086",
.of_match_table = of_match_ptr(max20086_dt_ids),
},
.probe_new = max20086_i2c_probe,
.id_table = max20086_i2c_id,
};
module_i2c_driver(max20086_regulator_driver);
MODULE_AUTHOR("Watson Chow <watson.chow@avnet.com>");
MODULE_DESCRIPTION("MAX20086-MAX20089 Camera Power Protector Driver");
MODULE_LICENSE("GPL");
|