1 // SPDX-License-Identifier: GPL-2.0-only
2 // Copyright (c) 2017, 2019-2020, The Linux Foundation. All rights reserved.
3 // Copyright (c) 2023, Linaro Limited
4 
5 #include <linux/bitfield.h>
6 #include <linux/module.h>
7 #include <linux/of.h>
8 #include <linux/platform_device.h>
9 #include <linux/regmap.h>
10 #include <linux/regulator/driver.h>
11 #include <linux/regulator/machine.h>
12 #include <linux/regulator/of_regulator.h>
13 
14 #define REFGEN_REG_BIAS_EN		0x08
15 #define REFGEN_BIAS_EN_MASK		GENMASK(2, 0)
16  #define REFGEN_BIAS_EN_ENABLE		0x7
17  #define REFGEN_BIAS_EN_DISABLE		0x6
18 
19 #define REFGEN_REG_BG_CTRL		0x14
20 #define REFGEN_BG_CTRL_MASK		GENMASK(2, 1)
21  #define REFGEN_BG_CTRL_ENABLE		0x3
22  #define REFGEN_BG_CTRL_DISABLE		0x2
23 
24 #define REFGEN_REG_PWRDWN_CTRL5		0x80
25 #define REFGEN_PWRDWN_CTRL5_MASK	BIT(0)
26  #define REFGEN_PWRDWN_CTRL5_ENABLE	0x1
27 
28 static int qcom_sdm845_refgen_enable(struct regulator_dev *rdev)
29 {
30 	regmap_update_bits(rdev->regmap, REFGEN_REG_BG_CTRL, REFGEN_BG_CTRL_MASK,
31 			   FIELD_PREP(REFGEN_BG_CTRL_MASK, REFGEN_BG_CTRL_ENABLE));
32 
33 	regmap_write(rdev->regmap, REFGEN_REG_BIAS_EN,
34 		     FIELD_PREP(REFGEN_BIAS_EN_MASK, REFGEN_BIAS_EN_ENABLE));
35 
36 	return 0;
37 }
38 
39 static int qcom_sdm845_refgen_disable(struct regulator_dev *rdev)
40 {
41 	regmap_write(rdev->regmap, REFGEN_REG_BIAS_EN,
42 		     FIELD_PREP(REFGEN_BIAS_EN_MASK, REFGEN_BIAS_EN_DISABLE));
43 
44 	regmap_update_bits(rdev->regmap, REFGEN_REG_BG_CTRL, REFGEN_BG_CTRL_MASK,
45 			   FIELD_PREP(REFGEN_BG_CTRL_MASK, REFGEN_BG_CTRL_DISABLE));
46 
47 	return 0;
48 }
49 
50 static int qcom_sdm845_refgen_is_enabled(struct regulator_dev *rdev)
51 {
52 	u32 val;
53 
54 	regmap_read(rdev->regmap, REFGEN_REG_BG_CTRL, &val);
55 	if (FIELD_GET(REFGEN_BG_CTRL_MASK, val) != REFGEN_BG_CTRL_ENABLE)
56 		return 0;
57 
58 	regmap_read(rdev->regmap, REFGEN_REG_BIAS_EN, &val);
59 	if (FIELD_GET(REFGEN_BIAS_EN_MASK, val) != REFGEN_BIAS_EN_ENABLE)
60 		return 0;
61 
62 	return 1;
63 }
64 
65 static struct regulator_desc sdm845_refgen_desc = {
66 	.enable_time = 5,
67 	.name = "refgen",
68 	.owner = THIS_MODULE,
69 	.type = REGULATOR_VOLTAGE,
70 	.ops = &(const struct regulator_ops) {
71 		.enable		= qcom_sdm845_refgen_enable,
72 		.disable	= qcom_sdm845_refgen_disable,
73 		.is_enabled	= qcom_sdm845_refgen_is_enabled,
74 	},
75 };
76 
77 static struct regulator_desc sm8250_refgen_desc = {
78 	.enable_reg = REFGEN_REG_PWRDWN_CTRL5,
79 	.enable_mask = REFGEN_PWRDWN_CTRL5_MASK,
80 	.enable_val = REFGEN_PWRDWN_CTRL5_ENABLE,
81 	.disable_val = 0,
82 	.enable_time = 5,
83 	.name = "refgen",
84 	.owner = THIS_MODULE,
85 	.type = REGULATOR_VOLTAGE,
86 	.ops = &(const struct regulator_ops) {
87 		.enable		= regulator_enable_regmap,
88 		.disable	= regulator_disable_regmap,
89 		.is_enabled	= regulator_is_enabled_regmap,
90 	},
91 };
92 
93 static const struct regmap_config qcom_refgen_regmap_config = {
94 	.reg_bits = 32,
95 	.reg_stride = 4,
96 	.val_bits = 32,
97 	.fast_io = true,
98 };
99 
100 static int qcom_refgen_probe(struct platform_device *pdev)
101 {
102 	struct regulator_init_data *init_data;
103 	struct regulator_config config = {};
104 	const struct regulator_desc *rdesc;
105 	struct device *dev = &pdev->dev;
106 	struct regulator_dev *rdev;
107 	struct regmap *regmap;
108 	void __iomem *base;
109 
110 	rdesc = of_device_get_match_data(dev);
111 	if (!rdesc)
112 		return -ENODATA;
113 
114 	base = devm_platform_ioremap_resource(pdev, 0);
115 	if (IS_ERR(base))
116 		return PTR_ERR(base);
117 
118 	regmap = devm_regmap_init_mmio(dev, base, &qcom_refgen_regmap_config);
119 	if (IS_ERR(regmap))
120 		return PTR_ERR(regmap);
121 
122 	init_data = of_get_regulator_init_data(dev, dev->of_node, rdesc);
123 	if (!init_data)
124 		return -ENOMEM;
125 
126 	config.dev = dev;
127 	config.init_data = init_data;
128 	config.of_node = dev->of_node;
129 	config.regmap = regmap;
130 
131 	rdev = devm_regulator_register(dev, rdesc, &config);
132 	if (IS_ERR(rdev))
133 		return PTR_ERR(rdev);
134 
135 	return 0;
136 }
137 
138 static const struct of_device_id qcom_refgen_match_table[] = {
139 	{ .compatible = "qcom,sdm845-refgen-regulator", .data = &sdm845_refgen_desc },
140 	{ .compatible = "qcom,sm8250-refgen-regulator", .data = &sm8250_refgen_desc },
141 	{ }
142 };
143 MODULE_DEVICE_TABLE(of, qcom_refgen_match_table);
144 
145 static struct platform_driver qcom_refgen_driver = {
146 	.probe = qcom_refgen_probe,
147 	.driver = {
148 		.name = "qcom-refgen-regulator",
149 		.of_match_table = qcom_refgen_match_table,
150 	},
151 };
152 module_platform_driver(qcom_refgen_driver);
153 
154 MODULE_LICENSE("GPL");
155 MODULE_DESCRIPTION("Qualcomm REFGEN regulator driver");
156