1 /*
2 * Copyright 2023 EPAM Systems
3 * SPDX-License-Identifier: Apache-2.0
4 */
5
6 #define DT_DRV_COMPAT regulator_gpio
7
8 #include <stdint.h>
9
10 #include <zephyr/drivers/regulator.h>
11 #include <zephyr/drivers/gpio.h>
12 #include <zephyr/logging/log.h>
13
14 LOG_MODULE_REGISTER(regulator_gpio, CONFIG_REGULATOR_LOG_LEVEL);
15
16 struct regulator_gpio_config {
17 struct regulator_common_config common;
18
19 const struct gpio_dt_spec *gpios;
20 uint8_t num_gpios;
21
22 const int32_t *states;
23 uint8_t states_cnt;
24
25 const struct gpio_dt_spec enable;
26 };
27
28 struct regulator_gpio_data {
29 struct regulator_common_data common;
30 int32_t current_volt_uv;
31 };
32
regulator_gpio_apply_state(const struct device * dev,uint32_t state)33 static int regulator_gpio_apply_state(const struct device *dev, uint32_t state)
34 {
35 const struct regulator_gpio_config *cfg = dev->config;
36
37 for (unsigned int gpio_idx = 0; gpio_idx < cfg->num_gpios; gpio_idx++) {
38 int ret;
39 int new_state_of_gpio = (state >> gpio_idx) & 0x1;
40
41 ret = gpio_pin_get_dt(&cfg->gpios[gpio_idx]);
42 if (ret < 0) {
43 LOG_ERR("%s: can't get pin state", dev->name);
44 return ret;
45 }
46
47 if (ret != new_state_of_gpio) {
48 ret = gpio_pin_set_dt(&cfg->gpios[gpio_idx], new_state_of_gpio);
49 if (ret < 0) {
50 LOG_ERR("%s: can't set pin state", dev->name);
51 return ret;
52 }
53 }
54 }
55
56 return 0;
57 }
58
regulator_gpio_enable(const struct device * dev)59 static int regulator_gpio_enable(const struct device *dev)
60 {
61 const struct regulator_gpio_config *cfg = dev->config;
62 int ret;
63
64 if (cfg->enable.port == NULL) {
65 return 0;
66 }
67
68 ret = gpio_pin_set_dt(&cfg->enable, 1);
69 if (ret < 0) {
70 LOG_ERR("%s: can't enable regulator!", dev->name);
71 return ret;
72 }
73
74 return 0;
75 }
76
regulator_gpio_disable(const struct device * dev)77 static int regulator_gpio_disable(const struct device *dev)
78 {
79 const struct regulator_gpio_config *cfg = dev->config;
80
81 if (cfg->enable.port == NULL) {
82 return 0;
83 }
84
85 return gpio_pin_set_dt(&cfg->enable, 0);
86 }
87
regulator_gpio_count_voltages(const struct device * dev)88 static unsigned int regulator_gpio_count_voltages(const struct device *dev)
89 {
90 const struct regulator_gpio_config *cfg = dev->config;
91
92 return cfg->states_cnt;
93 }
94
regulator_gpio_list_voltage(const struct device * dev,unsigned int idx,int32_t * volt_uv)95 static int regulator_gpio_list_voltage(const struct device *dev, unsigned int idx, int32_t *volt_uv)
96 {
97 const struct regulator_gpio_config *cfg = dev->config;
98
99 if (idx >= cfg->states_cnt) {
100 LOG_ERR("%s: can't get list voltage for idx %u", dev->name, idx);
101 return -EINVAL;
102 }
103
104 *volt_uv = cfg->states[idx * 2];
105 return 0;
106 }
107
regulator_gpio_set_voltage(const struct device * dev,int32_t min_uv,int32_t max_uv)108 static int regulator_gpio_set_voltage(const struct device *dev, int32_t min_uv, int32_t max_uv)
109 {
110 const struct regulator_gpio_config *cfg = dev->config;
111 struct regulator_gpio_data *data = dev->data;
112 int32_t best_voltage = INT32_MAX;
113 unsigned int best_state;
114 int ret = 0;
115
116 /* choose minimum possible voltage in range provided by a caller */
117 for (unsigned int state_idx = 0; state_idx < cfg->states_cnt; state_idx++) {
118 if (!IN_RANGE(cfg->states[state_idx * 2], min_uv, max_uv) ||
119 cfg->states[state_idx * 2] >= best_voltage) {
120 continue;
121 }
122
123 best_voltage = cfg->states[state_idx * 2];
124 best_state = cfg->states[state_idx * 2 + 1];
125 }
126
127 if (best_voltage == INT32_MAX) {
128 LOG_ERR("%s: can't find voltage is states", dev->name);
129 return -EINVAL;
130 }
131
132 if (best_voltage == data->current_volt_uv) {
133 return 0;
134 }
135
136 ret = regulator_gpio_apply_state(dev, best_state);
137 if (ret) {
138 return ret;
139 }
140
141 data->current_volt_uv = best_voltage;
142 return 0;
143 }
144
regulator_gpio_get_voltage(const struct device * dev,int32_t * volt_uv)145 static int regulator_gpio_get_voltage(const struct device *dev, int32_t *volt_uv)
146 {
147 const struct regulator_gpio_data *data = dev->data;
148
149 *volt_uv = data->current_volt_uv;
150 return 0;
151 }
152
153 static const struct regulator_driver_api regulator_gpio_api = {
154 .enable = regulator_gpio_enable,
155 .disable = regulator_gpio_disable,
156 .set_voltage = regulator_gpio_set_voltage,
157 .get_voltage = regulator_gpio_get_voltage,
158 .count_voltages = regulator_gpio_count_voltages,
159 .list_voltage = regulator_gpio_list_voltage,
160 };
161
regulator_gpio_init(const struct device * dev)162 static int regulator_gpio_init(const struct device *dev)
163 {
164 const struct regulator_gpio_config *cfg = dev->config;
165 int ret;
166
167 regulator_common_data_init(dev);
168
169 for (unsigned int gpio_idx = 0; gpio_idx < cfg->num_gpios; gpio_idx++) {
170 int ret;
171
172 if (!gpio_is_ready_dt(&cfg->gpios[gpio_idx])) {
173 LOG_ERR("%s: gpio pin: %s not ready", dev->name,
174 cfg->gpios[gpio_idx].port ? cfg->gpios[gpio_idx].port->name
175 : "null");
176 return -ENODEV;
177 }
178
179 ret = gpio_pin_configure_dt(&cfg->gpios[gpio_idx], GPIO_OUTPUT);
180 if (ret < 0) {
181 LOG_ERR("%s: can't configure pin (%d) as output", dev->name,
182 cfg->gpios[gpio_idx].pin);
183 return ret;
184 }
185 }
186
187 if (cfg->enable.port != NULL) {
188 if (!gpio_is_ready_dt(&cfg->enable)) {
189 LOG_ERR("%s: gpio pin: %s not ready", dev->name, cfg->enable.port->name);
190 return -ENODEV;
191 }
192
193 ret = gpio_pin_configure_dt(&cfg->enable, GPIO_OUTPUT | GPIO_OUTPUT_INIT_LOW);
194 if (ret < 0) {
195 LOG_ERR("%s: can't configure enable pin (%d) as output", dev->name,
196 cfg->enable.pin);
197 return ret;
198 }
199 }
200
201 return regulator_common_init(dev, false);
202 }
203
204 #define REG_GPIO_CONTEXT_GPIOS_SPEC_ELEM(_node_id, _prop, _idx) \
205 GPIO_DT_SPEC_GET_BY_IDX(_node_id, _prop, _idx),
206
207 #define REG_GPIO_CONTEXT_GPIOS_FOREACH_ELEM(inst) \
208 DT_FOREACH_PROP_ELEM(DT_DRV_INST(inst), gpios, REG_GPIO_CONTEXT_GPIOS_SPEC_ELEM)
209
210 #define REG_GPIO_CONTEXT_GPIOS_INITIALIZE(inst) \
211 .gpios = (const struct gpio_dt_spec[]){REG_GPIO_CONTEXT_GPIOS_FOREACH_ELEM(inst)}, \
212 .num_gpios = DT_INST_PROP_LEN(inst, gpios)
213
214 #define REGULATOR_GPIO_DEFINE(inst) \
215 static struct regulator_gpio_data data##inst = { \
216 .current_volt_uv = INT32_MAX, \
217 }; \
218 BUILD_ASSERT(!(DT_INST_PROP_LEN(inst, states) & 0x1), \
219 "Number of regulator states should be even"); \
220 static const struct regulator_gpio_config config##inst = { \
221 .common = REGULATOR_DT_INST_COMMON_CONFIG_INIT(inst), \
222 REG_GPIO_CONTEXT_GPIOS_INITIALIZE(inst), \
223 .enable = GPIO_DT_SPEC_INST_GET_OR(inst, enable_gpios, {0}), \
224 .states = ((const int[])DT_INST_PROP(inst, states)), \
225 .states_cnt = DT_INST_PROP_LEN(inst, states) / 2, \
226 }; \
227 DEVICE_DT_INST_DEFINE(inst, regulator_gpio_init, NULL, &data##inst, &config##inst, \
228 POST_KERNEL, CONFIG_REGULATOR_GPIO_INIT_PRIORITY, \
229 ®ulator_gpio_api);
230
231 DT_INST_FOREACH_STATUS_OKAY(REGULATOR_GPIO_DEFINE)
232
