1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) STMicroelectronics 2019
3 // Author(s): Fabrice Gasnier <fabrice.gasnier@st.com>.
4 
5 #include <linux/mfd/syscon.h>
6 #include <linux/module.h>
7 #include <linux/of_device.h>
8 #include <linux/platform_device.h>
9 #include <linux/regmap.h>
10 #include <linux/regulator/driver.h>
11 #include <linux/regulator/of_regulator.h>
12 
13 /* STM32H7 SYSCFG register */
14 #define STM32H7_SYSCFG_PMCR		0x04
15 #define STM32H7_SYSCFG_BOOSTE_MASK	BIT(8)
16 
17 /* STM32MP1 SYSCFG has set and clear registers */
18 #define STM32MP1_SYSCFG_PMCSETR		0x04
19 #define STM32MP1_SYSCFG_PMCCLRR		0x44
20 #define STM32MP1_SYSCFG_EN_BOOSTER_MASK	BIT(8)
21 
22 static const struct regulator_ops stm32h7_booster_ops = {
23 	.list_voltage	= regulator_list_voltage_linear,
24 	.enable		= regulator_enable_regmap,
25 	.disable	= regulator_disable_regmap,
26 	.is_enabled	= regulator_is_enabled_regmap,
27 };
28 
29 static const struct regulator_desc stm32h7_booster_desc = {
30 	.name = "booster",
31 	.supply_name = "vdda",
32 	.n_voltages = 1,
33 	.type = REGULATOR_VOLTAGE,
34 	.min_uV = 3300000,
35 	.fixed_uV = 3300000,
36 	.ramp_delay = 66000, /* up to 50us to stabilize */
37 	.ops = &stm32h7_booster_ops,
38 	.enable_reg = STM32H7_SYSCFG_PMCR,
39 	.enable_mask = STM32H7_SYSCFG_BOOSTE_MASK,
40 	.owner = THIS_MODULE,
41 };
42 
43 static int stm32mp1_booster_enable(struct regulator_dev *rdev)
44 {
45 	return regmap_write(rdev->regmap, STM32MP1_SYSCFG_PMCSETR,
46 			    STM32MP1_SYSCFG_EN_BOOSTER_MASK);
47 }
48 
49 static int stm32mp1_booster_disable(struct regulator_dev *rdev)
50 {
51 	return regmap_write(rdev->regmap, STM32MP1_SYSCFG_PMCCLRR,
52 			    STM32MP1_SYSCFG_EN_BOOSTER_MASK);
53 }
54 
55 static const struct regulator_ops stm32mp1_booster_ops = {
56 	.list_voltage	= regulator_list_voltage_linear,
57 	.enable		= stm32mp1_booster_enable,
58 	.disable	= stm32mp1_booster_disable,
59 	.is_enabled	= regulator_is_enabled_regmap,
60 };
61 
62 static const struct regulator_desc stm32mp1_booster_desc = {
63 	.name = "booster",
64 	.supply_name = "vdda",
65 	.n_voltages = 1,
66 	.type = REGULATOR_VOLTAGE,
67 	.min_uV = 3300000,
68 	.fixed_uV = 3300000,
69 	.ramp_delay = 66000,
70 	.ops = &stm32mp1_booster_ops,
71 	.enable_reg = STM32MP1_SYSCFG_PMCSETR,
72 	.enable_mask = STM32MP1_SYSCFG_EN_BOOSTER_MASK,
73 	.owner = THIS_MODULE,
74 };
75 
76 static int stm32_booster_probe(struct platform_device *pdev)
77 {
78 	struct device *dev = &pdev->dev;
79 	struct device_node *np = pdev->dev.of_node;
80 	struct regulator_config config = { };
81 	const struct regulator_desc *desc;
82 	struct regulator_dev *rdev;
83 	struct regmap *regmap;
84 	int ret;
85 
86 	regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
87 	if (IS_ERR(regmap))
88 		return PTR_ERR(regmap);
89 
90 	desc = (const struct regulator_desc *)
91 		of_match_device(dev->driver->of_match_table, dev)->data;
92 
93 	config.regmap = regmap;
94 	config.dev = dev;
95 	config.of_node = np;
96 	config.init_data = of_get_regulator_init_data(dev, np, desc);
97 
98 	rdev = devm_regulator_register(dev, desc, &config);
99 	if (IS_ERR(rdev)) {
100 		ret = PTR_ERR(rdev);
101 		dev_err(dev, "register failed with error %d\n", ret);
102 		return ret;
103 	}
104 
105 	return 0;
106 }
107 
108 static const struct of_device_id stm32_booster_of_match[] = {
109 	{
110 		.compatible = "st,stm32h7-booster",
111 		.data = (void *)&stm32h7_booster_desc
112 	}, {
113 		.compatible = "st,stm32mp1-booster",
114 		.data = (void *)&stm32mp1_booster_desc
115 	}, {
116 	},
117 };
118 MODULE_DEVICE_TABLE(of, stm32_booster_of_match);
119 
120 static struct platform_driver stm32_booster_driver = {
121 	.probe = stm32_booster_probe,
122 	.driver = {
123 		.name  = "stm32-booster",
124 		.of_match_table = of_match_ptr(stm32_booster_of_match),
125 	},
126 };
127 module_platform_driver(stm32_booster_driver);
128 
129 MODULE_LICENSE("GPL v2");
130 MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
131 MODULE_DESCRIPTION("STMicroelectronics STM32 booster regulator driver");
132 MODULE_ALIAS("platform:stm32-booster");
133