1bfff546aSWatson Chow // SPDX-License-Identifier: GPL-2.0-or-later
2bfff546aSWatson Chow //
3bfff546aSWatson Chow // max20086-regulator.c - MAX20086-MAX20089 camera power protector driver
4bfff546aSWatson Chow //
5bfff546aSWatson Chow // Copyright (C) 2022 Laurent Pinchart <laurent.pinchart@idesonboard.com>
6bfff546aSWatson Chow // Copyright (C) 2018 Avnet, Inc.
7bfff546aSWatson Chow
8bfff546aSWatson Chow #include <linux/err.h>
9b4c18c18SRandy Dunlap #include <linux/gpio/consumer.h>
10bfff546aSWatson Chow #include <linux/i2c.h>
11bfff546aSWatson Chow #include <linux/module.h>
12bfff546aSWatson Chow #include <linux/regmap.h>
13bfff546aSWatson Chow #include <linux/regulator/driver.h>
14bfff546aSWatson Chow #include <linux/regulator/machine.h>
15bfff546aSWatson Chow #include <linux/regulator/of_regulator.h>
16bfff546aSWatson Chow #include <linux/slab.h>
17bfff546aSWatson Chow
18bfff546aSWatson Chow /* Register Offset */
19bfff546aSWatson Chow #define MAX20086_REG_MASK 0x00
20bfff546aSWatson Chow #define MAX20086_REG_CONFIG 0x01
21bfff546aSWatson Chow #define MAX20086_REG_ID 0x02
22bfff546aSWatson Chow #define MAX20086_REG_STAT1 0x03
23bfff546aSWatson Chow #define MAX20086_REG_STAT2_L 0x04
24bfff546aSWatson Chow #define MAX20086_REG_STAT2_H 0x05
25bfff546aSWatson Chow #define MAX20086_REG_ADC1 0x06
26bfff546aSWatson Chow #define MAX20086_REG_ADC2 0x07
27bfff546aSWatson Chow #define MAX20086_REG_ADC3 0x08
28bfff546aSWatson Chow #define MAX20086_REG_ADC4 0x09
29bfff546aSWatson Chow
30bfff546aSWatson Chow /* DEVICE IDs */
31bfff546aSWatson Chow #define MAX20086_DEVICE_ID_MAX20086 0x40
32bfff546aSWatson Chow #define MAX20086_DEVICE_ID_MAX20087 0x20
33bfff546aSWatson Chow #define MAX20086_DEVICE_ID_MAX20088 0x10
34bfff546aSWatson Chow #define MAX20086_DEVICE_ID_MAX20089 0x00
35bfff546aSWatson Chow #define DEVICE_ID_MASK 0xf0
36bfff546aSWatson Chow
37bfff546aSWatson Chow /* Register bits */
38bfff546aSWatson Chow #define MAX20086_EN_MASK 0x0f
39bfff546aSWatson Chow #define MAX20086_EN_OUT1 0x01
40bfff546aSWatson Chow #define MAX20086_EN_OUT2 0x02
41bfff546aSWatson Chow #define MAX20086_EN_OUT3 0x04
42bfff546aSWatson Chow #define MAX20086_EN_OUT4 0x08
43bfff546aSWatson Chow #define MAX20086_INT_DISABLE_ALL 0x3f
44bfff546aSWatson Chow
45bfff546aSWatson Chow #define MAX20086_MAX_REGULATORS 4
46bfff546aSWatson Chow
47bfff546aSWatson Chow struct max20086_chip_info {
48bfff546aSWatson Chow u8 id;
49bfff546aSWatson Chow unsigned int num_outputs;
50bfff546aSWatson Chow };
51bfff546aSWatson Chow
52bfff546aSWatson Chow struct max20086_regulator {
53bfff546aSWatson Chow struct device_node *of_node;
54bfff546aSWatson Chow struct regulator_init_data *init_data;
55bfff546aSWatson Chow const struct regulator_desc *desc;
56bfff546aSWatson Chow struct regulator_dev *rdev;
57bfff546aSWatson Chow };
58bfff546aSWatson Chow
59bfff546aSWatson Chow struct max20086 {
60bfff546aSWatson Chow struct device *dev;
61bfff546aSWatson Chow struct regmap *regmap;
62bfff546aSWatson Chow struct gpio_desc *ena_gpiod;
63bfff546aSWatson Chow
64bfff546aSWatson Chow const struct max20086_chip_info *info;
65bfff546aSWatson Chow
66bfff546aSWatson Chow struct max20086_regulator regulators[MAX20086_MAX_REGULATORS];
67bfff546aSWatson Chow };
68bfff546aSWatson Chow
69bfff546aSWatson Chow static const struct regulator_ops max20086_buck_ops = {
70bfff546aSWatson Chow .enable = regulator_enable_regmap,
71bfff546aSWatson Chow .disable = regulator_disable_regmap,
72bfff546aSWatson Chow .is_enabled = regulator_is_enabled_regmap,
73bfff546aSWatson Chow };
74bfff546aSWatson Chow
75bfff546aSWatson Chow #define MAX20086_REGULATOR_DESC(n) \
76bfff546aSWatson Chow { \
77bfff546aSWatson Chow .name = "OUT"#n, \
78bfff546aSWatson Chow .supply_name = "in", \
79bfff546aSWatson Chow .id = (n) - 1, \
80bfff546aSWatson Chow .ops = &max20086_buck_ops, \
81bfff546aSWatson Chow .type = REGULATOR_VOLTAGE, \
82bfff546aSWatson Chow .owner = THIS_MODULE, \
83bfff546aSWatson Chow .enable_reg = MAX20086_REG_CONFIG, \
84bfff546aSWatson Chow .enable_mask = 1 << ((n) - 1), \
85bfff546aSWatson Chow .enable_val = 1 << ((n) - 1), \
86bfff546aSWatson Chow .disable_val = 0, \
87bfff546aSWatson Chow }
88bfff546aSWatson Chow
89bfff546aSWatson Chow static const char * const max20086_output_names[] = {
90bfff546aSWatson Chow "OUT1",
91bfff546aSWatson Chow "OUT2",
92bfff546aSWatson Chow "OUT3",
93bfff546aSWatson Chow "OUT4",
94bfff546aSWatson Chow };
95bfff546aSWatson Chow
96bfff546aSWatson Chow static const struct regulator_desc max20086_regulators[] = {
97bfff546aSWatson Chow MAX20086_REGULATOR_DESC(1),
98bfff546aSWatson Chow MAX20086_REGULATOR_DESC(2),
99bfff546aSWatson Chow MAX20086_REGULATOR_DESC(3),
100bfff546aSWatson Chow MAX20086_REGULATOR_DESC(4),
101bfff546aSWatson Chow };
102bfff546aSWatson Chow
max20086_regulators_register(struct max20086 * chip)103bfff546aSWatson Chow static int max20086_regulators_register(struct max20086 *chip)
104bfff546aSWatson Chow {
105bfff546aSWatson Chow unsigned int i;
106bfff546aSWatson Chow
107bfff546aSWatson Chow for (i = 0; i < chip->info->num_outputs; i++) {
108bfff546aSWatson Chow struct max20086_regulator *reg = &chip->regulators[i];
109bfff546aSWatson Chow struct regulator_config config = { };
110bfff546aSWatson Chow struct regulator_dev *rdev;
111bfff546aSWatson Chow
112bfff546aSWatson Chow config.dev = chip->dev;
113bfff546aSWatson Chow config.init_data = reg->init_data;
114bfff546aSWatson Chow config.driver_data = chip;
115bfff546aSWatson Chow config.of_node = reg->of_node;
116bfff546aSWatson Chow config.regmap = chip->regmap;
117bfff546aSWatson Chow config.ena_gpiod = chip->ena_gpiod;
118bfff546aSWatson Chow
119bfff546aSWatson Chow rdev = devm_regulator_register(chip->dev, reg->desc, &config);
120bfff546aSWatson Chow if (IS_ERR(rdev)) {
121bfff546aSWatson Chow dev_err(chip->dev,
122bfff546aSWatson Chow "Failed to register regulator output %s\n",
123bfff546aSWatson Chow reg->desc->name);
124bfff546aSWatson Chow return PTR_ERR(rdev);
125bfff546aSWatson Chow }
126bfff546aSWatson Chow
127bfff546aSWatson Chow reg->rdev = rdev;
128bfff546aSWatson Chow }
129bfff546aSWatson Chow
130bfff546aSWatson Chow return 0;
131bfff546aSWatson Chow }
132bfff546aSWatson Chow
max20086_parse_regulators_dt(struct max20086 * chip,bool * boot_on)133bfff546aSWatson Chow static int max20086_parse_regulators_dt(struct max20086 *chip, bool *boot_on)
134bfff546aSWatson Chow {
135bfff546aSWatson Chow struct of_regulator_match matches[MAX20086_MAX_REGULATORS] = { };
136bfff546aSWatson Chow struct device_node *node;
137bfff546aSWatson Chow unsigned int i;
138bfff546aSWatson Chow int ret;
139bfff546aSWatson Chow
140bfff546aSWatson Chow node = of_get_child_by_name(chip->dev->of_node, "regulators");
141bfff546aSWatson Chow if (!node) {
142bfff546aSWatson Chow dev_err(chip->dev, "regulators node not found\n");
143879cf800SDan Carpenter return -ENODEV;
144bfff546aSWatson Chow }
145bfff546aSWatson Chow
146bfff546aSWatson Chow for (i = 0; i < chip->info->num_outputs; ++i)
147bfff546aSWatson Chow matches[i].name = max20086_output_names[i];
148bfff546aSWatson Chow
149bfff546aSWatson Chow ret = of_regulator_match(chip->dev, node, matches,
150bfff546aSWatson Chow chip->info->num_outputs);
151bfff546aSWatson Chow of_node_put(node);
152bfff546aSWatson Chow if (ret < 0) {
153bfff546aSWatson Chow dev_err(chip->dev, "Failed to match regulators\n");
154bfff546aSWatson Chow return -EINVAL;
155bfff546aSWatson Chow }
156bfff546aSWatson Chow
157bfff546aSWatson Chow *boot_on = false;
158bfff546aSWatson Chow
159bfff546aSWatson Chow for (i = 0; i < chip->info->num_outputs; i++) {
160bfff546aSWatson Chow struct max20086_regulator *reg = &chip->regulators[i];
161bfff546aSWatson Chow
162bfff546aSWatson Chow reg->init_data = matches[i].init_data;
163bfff546aSWatson Chow reg->of_node = matches[i].of_node;
164bfff546aSWatson Chow reg->desc = &max20086_regulators[i];
165bfff546aSWatson Chow
166bfff546aSWatson Chow if (reg->init_data) {
167bfff546aSWatson Chow if (reg->init_data->constraints.always_on ||
168bfff546aSWatson Chow reg->init_data->constraints.boot_on)
169bfff546aSWatson Chow *boot_on = true;
170bfff546aSWatson Chow }
171bfff546aSWatson Chow }
172bfff546aSWatson Chow
173bfff546aSWatson Chow return 0;
174bfff546aSWatson Chow }
175bfff546aSWatson Chow
max20086_detect(struct max20086 * chip)176bfff546aSWatson Chow static int max20086_detect(struct max20086 *chip)
177bfff546aSWatson Chow {
178bfff546aSWatson Chow unsigned int data;
179bfff546aSWatson Chow int ret;
180bfff546aSWatson Chow
181bfff546aSWatson Chow ret = regmap_read(chip->regmap, MAX20086_REG_ID, &data);
182bfff546aSWatson Chow if (ret < 0) {
183bfff546aSWatson Chow dev_err(chip->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
184bfff546aSWatson Chow return ret;
185bfff546aSWatson Chow }
186bfff546aSWatson Chow
187bfff546aSWatson Chow if ((data & DEVICE_ID_MASK) != chip->info->id) {
188bfff546aSWatson Chow dev_err(chip->dev, "Invalid device ID 0x%02x\n", data);
189bfff546aSWatson Chow return -ENXIO;
190bfff546aSWatson Chow }
191bfff546aSWatson Chow
192bfff546aSWatson Chow return 0;
193bfff546aSWatson Chow }
194bfff546aSWatson Chow
max20086_gen_is_writeable_reg(struct device * dev,unsigned int reg)195bfff546aSWatson Chow static bool max20086_gen_is_writeable_reg(struct device *dev, unsigned int reg)
196bfff546aSWatson Chow {
197bfff546aSWatson Chow switch (reg) {
198bfff546aSWatson Chow case MAX20086_REG_MASK:
199bfff546aSWatson Chow case MAX20086_REG_CONFIG:
200bfff546aSWatson Chow return true;
201bfff546aSWatson Chow default:
202bfff546aSWatson Chow return false;
203bfff546aSWatson Chow }
204bfff546aSWatson Chow }
205bfff546aSWatson Chow
206bfff546aSWatson Chow static const struct regmap_config max20086_regmap_config = {
207bfff546aSWatson Chow .reg_bits = 8,
208bfff546aSWatson Chow .val_bits = 8,
209bfff546aSWatson Chow .writeable_reg = max20086_gen_is_writeable_reg,
210bfff546aSWatson Chow .max_register = 0x9,
211bfff546aSWatson Chow .cache_type = REGCACHE_NONE,
212bfff546aSWatson Chow };
213bfff546aSWatson Chow
max20086_i2c_probe(struct i2c_client * i2c)214bfff546aSWatson Chow static int max20086_i2c_probe(struct i2c_client *i2c)
215bfff546aSWatson Chow {
216bfff546aSWatson Chow struct max20086 *chip;
217bfff546aSWatson Chow enum gpiod_flags flags;
218bfff546aSWatson Chow bool boot_on;
219bfff546aSWatson Chow int ret;
220bfff546aSWatson Chow
221bfff546aSWatson Chow chip = devm_kzalloc(&i2c->dev, sizeof(*chip), GFP_KERNEL);
222bfff546aSWatson Chow if (!chip)
223bfff546aSWatson Chow return -ENOMEM;
224bfff546aSWatson Chow
225bfff546aSWatson Chow chip->dev = &i2c->dev;
226bfff546aSWatson Chow chip->info = device_get_match_data(chip->dev);
227bfff546aSWatson Chow
228bfff546aSWatson Chow i2c_set_clientdata(i2c, chip);
229bfff546aSWatson Chow
230bfff546aSWatson Chow chip->regmap = devm_regmap_init_i2c(i2c, &max20086_regmap_config);
231bfff546aSWatson Chow if (IS_ERR(chip->regmap)) {
232bfff546aSWatson Chow ret = PTR_ERR(chip->regmap);
233bfff546aSWatson Chow dev_err(chip->dev, "Failed to allocate register map: %d\n", ret);
234bfff546aSWatson Chow return ret;
235bfff546aSWatson Chow }
236bfff546aSWatson Chow
237bfff546aSWatson Chow ret = max20086_parse_regulators_dt(chip, &boot_on);
238bfff546aSWatson Chow if (ret < 0)
239bfff546aSWatson Chow return ret;
240bfff546aSWatson Chow
241bfff546aSWatson Chow ret = max20086_detect(chip);
242bfff546aSWatson Chow if (ret < 0)
243bfff546aSWatson Chow return ret;
244bfff546aSWatson Chow
245bfff546aSWatson Chow /* Until IRQ support is added, just disable all interrupts. */
246bfff546aSWatson Chow ret = regmap_update_bits(chip->regmap, MAX20086_REG_MASK,
247bfff546aSWatson Chow MAX20086_INT_DISABLE_ALL,
248bfff546aSWatson Chow MAX20086_INT_DISABLE_ALL);
249bfff546aSWatson Chow if (ret < 0) {
250bfff546aSWatson Chow dev_err(chip->dev, "Failed to disable interrupts: %d\n", ret);
251bfff546aSWatson Chow return ret;
252bfff546aSWatson Chow }
253bfff546aSWatson Chow
254bfff546aSWatson Chow /*
255bfff546aSWatson Chow * Get the enable GPIO. If any of the outputs is marked as being
256bfff546aSWatson Chow * enabled at boot, request the GPIO with an initial high state to
257bfff546aSWatson Chow * avoid disabling outputs that may have been turned on by the boot
258bfff546aSWatson Chow * loader. Otherwise, request it with a low state to enter lower-power
259bfff546aSWatson Chow * shutdown.
260bfff546aSWatson Chow */
261bfff546aSWatson Chow flags = boot_on ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
262bfff546aSWatson Chow chip->ena_gpiod = devm_gpiod_get(chip->dev, "enable", flags);
263bfff546aSWatson Chow if (IS_ERR(chip->ena_gpiod)) {
264bfff546aSWatson Chow ret = PTR_ERR(chip->ena_gpiod);
265bfff546aSWatson Chow dev_err(chip->dev, "Failed to get enable GPIO: %d\n", ret);
266bfff546aSWatson Chow return ret;
267bfff546aSWatson Chow }
268bfff546aSWatson Chow
269bfff546aSWatson Chow ret = max20086_regulators_register(chip);
270bfff546aSWatson Chow if (ret < 0) {
271bfff546aSWatson Chow dev_err(chip->dev, "Failed to register regulators: %d\n", ret);
272bfff546aSWatson Chow return ret;
273bfff546aSWatson Chow }
274bfff546aSWatson Chow
275bfff546aSWatson Chow return 0;
276bfff546aSWatson Chow }
277bfff546aSWatson Chow
278bfff546aSWatson Chow static const struct i2c_device_id max20086_i2c_id[] = {
279bfff546aSWatson Chow { "max20086" },
280bfff546aSWatson Chow { "max20087" },
281bfff546aSWatson Chow { "max20088" },
282bfff546aSWatson Chow { "max20089" },
283bfff546aSWatson Chow { /* Sentinel */ },
284bfff546aSWatson Chow };
285bfff546aSWatson Chow
286bfff546aSWatson Chow MODULE_DEVICE_TABLE(i2c, max20086_i2c_id);
287bfff546aSWatson Chow
2884a585086SKrzysztof Kozlowski static const struct of_device_id max20086_dt_ids[] __maybe_unused = {
289bfff546aSWatson Chow {
290bfff546aSWatson Chow .compatible = "maxim,max20086",
291bfff546aSWatson Chow .data = &(const struct max20086_chip_info) {
292bfff546aSWatson Chow .id = MAX20086_DEVICE_ID_MAX20086,
293bfff546aSWatson Chow .num_outputs = 4,
294bfff546aSWatson Chow }
295bfff546aSWatson Chow }, {
296bfff546aSWatson Chow .compatible = "maxim,max20087",
297bfff546aSWatson Chow .data = &(const struct max20086_chip_info) {
298bfff546aSWatson Chow .id = MAX20086_DEVICE_ID_MAX20087,
299bfff546aSWatson Chow .num_outputs = 4,
300bfff546aSWatson Chow }
301bfff546aSWatson Chow }, {
302bfff546aSWatson Chow .compatible = "maxim,max20088",
303bfff546aSWatson Chow .data = &(const struct max20086_chip_info) {
304bfff546aSWatson Chow .id = MAX20086_DEVICE_ID_MAX20088,
305bfff546aSWatson Chow .num_outputs = 2,
306bfff546aSWatson Chow }
307bfff546aSWatson Chow }, {
308bfff546aSWatson Chow .compatible = "maxim,max20089",
309bfff546aSWatson Chow .data = &(const struct max20086_chip_info) {
310bfff546aSWatson Chow .id = MAX20086_DEVICE_ID_MAX20089,
311bfff546aSWatson Chow .num_outputs = 2,
312bfff546aSWatson Chow }
313bfff546aSWatson Chow },
314bfff546aSWatson Chow { /* Sentinel */ },
315bfff546aSWatson Chow };
316bfff546aSWatson Chow
317bfff546aSWatson Chow MODULE_DEVICE_TABLE(of, max20086_dt_ids);
318bfff546aSWatson Chow
319bfff546aSWatson Chow static struct i2c_driver max20086_regulator_driver = {
320bfff546aSWatson Chow .driver = {
321bfff546aSWatson Chow .name = "max20086",
32241cff178SDouglas Anderson .probe_type = PROBE_PREFER_ASYNCHRONOUS,
323bfff546aSWatson Chow .of_match_table = of_match_ptr(max20086_dt_ids),
324bfff546aSWatson Chow },
325*964e1865SUwe Kleine-König .probe = max20086_i2c_probe,
326bfff546aSWatson Chow .id_table = max20086_i2c_id,
327bfff546aSWatson Chow };
328bfff546aSWatson Chow
329bfff546aSWatson Chow module_i2c_driver(max20086_regulator_driver);
330bfff546aSWatson Chow
331bfff546aSWatson Chow MODULE_AUTHOR("Watson Chow <watson.chow@avnet.com>");
332bfff546aSWatson Chow MODULE_DESCRIPTION("MAX20086-MAX20089 Camera Power Protector Driver");
333bfff546aSWatson Chow MODULE_LICENSE("GPL");
334