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21#include <linux/err.h>
22#include <linux/mutex.h>
23#include <linux/module.h>
24#include <linux/platform_device.h>
25#include <linux/regulator/driver.h>
26#include <linux/regulator/fixed.h>
27#include <linux/gpio.h>
28#include <linux/slab.h>
29#include <linux/of.h>
30#include <linux/of_gpio.h>
31#include <linux/regulator/of_regulator.h>
32#include <linux/regulator/machine.h>
33
34struct fixed_voltage_data {
35 struct regulator_desc desc;
36 struct regulator_dev *dev;
37};
38
39
40
41
42
43
44
45
46
47
48
49static struct fixed_voltage_config *
50of_get_fixed_voltage_config(struct device *dev,
51 const struct regulator_desc *desc)
52{
53 struct fixed_voltage_config *config;
54 struct device_node *np = dev->of_node;
55 struct regulator_init_data *init_data;
56
57 config = devm_kzalloc(dev, sizeof(struct fixed_voltage_config),
58 GFP_KERNEL);
59 if (!config)
60 return ERR_PTR(-ENOMEM);
61
62 config->init_data = of_get_regulator_init_data(dev, dev->of_node, desc);
63 if (!config->init_data)
64 return ERR_PTR(-EINVAL);
65
66 init_data = config->init_data;
67 init_data->constraints.apply_uV = 0;
68
69 config->supply_name = init_data->constraints.name;
70 if (init_data->constraints.min_uV == init_data->constraints.max_uV) {
71 config->microvolts = init_data->constraints.min_uV;
72 } else {
73 dev_err(dev,
74 "Fixed regulator specified with variable voltages\n");
75 return ERR_PTR(-EINVAL);
76 }
77
78 if (init_data->constraints.boot_on)
79 config->enabled_at_boot = true;
80
81 config->gpio = of_get_named_gpio(np, "gpio", 0);
82 if ((config->gpio < 0) && (config->gpio != -ENOENT))
83 return ERR_PTR(config->gpio);
84
85 of_property_read_u32(np, "startup-delay-us", &config->startup_delay);
86
87 config->enable_high = of_property_read_bool(np, "enable-active-high");
88 config->gpio_is_open_drain = of_property_read_bool(np,
89 "gpio-open-drain");
90
91 if (of_find_property(np, "vin-supply", NULL))
92 config->input_supply = "vin";
93
94 return config;
95}
96
97static struct regulator_ops fixed_voltage_ops = {
98};
99
100static int reg_fixed_voltage_probe(struct platform_device *pdev)
101{
102 struct fixed_voltage_config *config;
103 struct fixed_voltage_data *drvdata;
104 struct regulator_config cfg = { };
105 int ret;
106
107 drvdata = devm_kzalloc(&pdev->dev, sizeof(struct fixed_voltage_data),
108 GFP_KERNEL);
109 if (!drvdata)
110 return -ENOMEM;
111
112 if (pdev->dev.of_node) {
113 config = of_get_fixed_voltage_config(&pdev->dev,
114 &drvdata->desc);
115 if (IS_ERR(config))
116 return PTR_ERR(config);
117 } else {
118 config = dev_get_platdata(&pdev->dev);
119 }
120
121 if (!config)
122 return -ENOMEM;
123
124 drvdata->desc.name = devm_kstrdup(&pdev->dev,
125 config->supply_name,
126 GFP_KERNEL);
127 if (drvdata->desc.name == NULL) {
128 dev_err(&pdev->dev, "Failed to allocate supply name\n");
129 return -ENOMEM;
130 }
131 drvdata->desc.type = REGULATOR_VOLTAGE;
132 drvdata->desc.owner = THIS_MODULE;
133 drvdata->desc.ops = &fixed_voltage_ops;
134
135 drvdata->desc.enable_time = config->startup_delay;
136
137 if (config->input_supply) {
138 drvdata->desc.supply_name = devm_kstrdup(&pdev->dev,
139 config->input_supply,
140 GFP_KERNEL);
141 if (!drvdata->desc.supply_name) {
142 dev_err(&pdev->dev,
143 "Failed to allocate input supply\n");
144 return -ENOMEM;
145 }
146 }
147
148 if (config->microvolts)
149 drvdata->desc.n_voltages = 1;
150
151 drvdata->desc.fixed_uV = config->microvolts;
152
153 if (gpio_is_valid(config->gpio)) {
154 cfg.ena_gpio = config->gpio;
155 if (pdev->dev.of_node)
156 cfg.ena_gpio_initialized = true;
157 }
158 cfg.ena_gpio_invert = !config->enable_high;
159 if (config->enabled_at_boot) {
160 if (config->enable_high)
161 cfg.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
162 else
163 cfg.ena_gpio_flags |= GPIOF_OUT_INIT_LOW;
164 } else {
165 if (config->enable_high)
166 cfg.ena_gpio_flags |= GPIOF_OUT_INIT_LOW;
167 else
168 cfg.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
169 }
170 if (config->gpio_is_open_drain)
171 cfg.ena_gpio_flags |= GPIOF_OPEN_DRAIN;
172
173 cfg.dev = &pdev->dev;
174 cfg.init_data = config->init_data;
175 cfg.driver_data = drvdata;
176 cfg.of_node = pdev->dev.of_node;
177
178 drvdata->dev = devm_regulator_register(&pdev->dev, &drvdata->desc,
179 &cfg);
180 if (IS_ERR(drvdata->dev)) {
181 ret = PTR_ERR(drvdata->dev);
182 dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);
183 return ret;
184 }
185
186 platform_set_drvdata(pdev, drvdata);
187
188 dev_dbg(&pdev->dev, "%s supplying %duV\n", drvdata->desc.name,
189 drvdata->desc.fixed_uV);
190
191 return 0;
192}
193
194#if defined(CONFIG_OF)
195static const struct of_device_id fixed_of_match[] = {
196 { .compatible = "regulator-fixed", },
197 {},
198};
199MODULE_DEVICE_TABLE(of, fixed_of_match);
200#endif
201
202static struct platform_driver regulator_fixed_voltage_driver = {
203 .probe = reg_fixed_voltage_probe,
204 .driver = {
205 .name = "reg-fixed-voltage",
206 .of_match_table = of_match_ptr(fixed_of_match),
207 },
208};
209
210static int __init regulator_fixed_voltage_init(void)
211{
212 return platform_driver_register(®ulator_fixed_voltage_driver);
213}
214subsys_initcall(regulator_fixed_voltage_init);
215
216static void __exit regulator_fixed_voltage_exit(void)
217{
218 platform_driver_unregister(®ulator_fixed_voltage_driver);
219}
220module_exit(regulator_fixed_voltage_exit);
221
222MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
223MODULE_DESCRIPTION("Fixed voltage regulator");
224MODULE_LICENSE("GPL");
225MODULE_ALIAS("platform:reg-fixed-voltage");
226
