1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | // |
3 | // sy8106a-regulator.c - Regulator device driver for SY8106A |
4 | // |
5 | // Copyright (C) 2016 Ondřej Jirman <megous@megous.com> |
6 | // Copyright (c) 2017-2018 Icenowy Zheng <icenowy@aosc.io> |
7 | |
8 | #include <linux/err.h> |
9 | #include <linux/i2c.h> |
10 | #include <linux/module.h> |
11 | #include <linux/regmap.h> |
12 | #include <linux/regulator/driver.h> |
13 | #include <linux/regulator/of_regulator.h> |
14 | |
15 | #define SY8106A_REG_VOUT1_SEL 0x01 |
16 | #define SY8106A_REG_VOUT_COM 0x02 |
17 | #define SY8106A_REG_VOUT1_SEL_MASK 0x7f |
18 | #define SY8106A_DISABLE_REG BIT(0) |
19 | /* |
20 | * The I2C controlled voltage will only work when this bit is set; otherwise |
21 | * it will behave like a fixed regulator. |
22 | */ |
23 | #define SY8106A_GO_BIT BIT(7) |
24 | |
25 | static const struct regmap_config sy8106a_regmap_config = { |
26 | .reg_bits = 8, |
27 | .val_bits = 8, |
28 | }; |
29 | |
30 | static const struct regulator_ops sy8106a_ops = { |
31 | .set_voltage_sel = regulator_set_voltage_sel_regmap, |
32 | .set_voltage_time_sel = regulator_set_voltage_time_sel, |
33 | .get_voltage_sel = regulator_get_voltage_sel_regmap, |
34 | .list_voltage = regulator_list_voltage_linear, |
35 | /* Enabling/disabling the regulator is not yet implemented */ |
36 | }; |
37 | |
38 | /* Default limits measured in millivolts */ |
39 | #define SY8106A_MIN_MV 680 |
40 | #define SY8106A_MAX_MV 1950 |
41 | #define SY8106A_STEP_MV 10 |
42 | |
43 | static const struct regulator_desc sy8106a_reg = { |
44 | .name = "SY8106A" , |
45 | .id = 0, |
46 | .ops = &sy8106a_ops, |
47 | .type = REGULATOR_VOLTAGE, |
48 | .n_voltages = ((SY8106A_MAX_MV - SY8106A_MIN_MV) / SY8106A_STEP_MV) + 1, |
49 | .min_uV = (SY8106A_MIN_MV * 1000), |
50 | .uV_step = (SY8106A_STEP_MV * 1000), |
51 | .vsel_reg = SY8106A_REG_VOUT1_SEL, |
52 | .vsel_mask = SY8106A_REG_VOUT1_SEL_MASK, |
53 | /* |
54 | * This ramp_delay is a conservative default value which works on |
55 | * H3/H5 boards VDD-CPUX situations. |
56 | */ |
57 | .ramp_delay = 200, |
58 | .owner = THIS_MODULE, |
59 | }; |
60 | |
61 | /* |
62 | * I2C driver interface functions |
63 | */ |
64 | static int sy8106a_i2c_probe(struct i2c_client *i2c) |
65 | { |
66 | struct device *dev = &i2c->dev; |
67 | struct regulator_dev *rdev; |
68 | struct regulator_config config = { }; |
69 | struct regmap *regmap; |
70 | unsigned int reg, vsel; |
71 | u32 fixed_voltage; |
72 | int error; |
73 | |
74 | error = of_property_read_u32(np: dev->of_node, propname: "silergy,fixed-microvolt" , |
75 | out_value: &fixed_voltage); |
76 | if (error) |
77 | return error; |
78 | |
79 | if (fixed_voltage < SY8106A_MIN_MV * 1000 || |
80 | fixed_voltage > SY8106A_MAX_MV * 1000) |
81 | return -EINVAL; |
82 | |
83 | regmap = devm_regmap_init_i2c(i2c, &sy8106a_regmap_config); |
84 | if (IS_ERR(ptr: regmap)) { |
85 | error = PTR_ERR(ptr: regmap); |
86 | dev_err(dev, "Failed to allocate register map: %d\n" , error); |
87 | return error; |
88 | } |
89 | |
90 | config.dev = &i2c->dev; |
91 | config.regmap = regmap; |
92 | |
93 | config.of_node = dev->of_node; |
94 | config.init_data = of_get_regulator_init_data(dev, node: dev->of_node, |
95 | desc: &sy8106a_reg); |
96 | |
97 | if (!config.init_data) |
98 | return -ENOMEM; |
99 | |
100 | /* Ensure GO_BIT is enabled when probing */ |
101 | error = regmap_read(map: regmap, SY8106A_REG_VOUT1_SEL, val: ®); |
102 | if (error) |
103 | return error; |
104 | |
105 | if (!(reg & SY8106A_GO_BIT)) { |
106 | vsel = (fixed_voltage / 1000 - SY8106A_MIN_MV) / |
107 | SY8106A_STEP_MV; |
108 | |
109 | error = regmap_write(map: regmap, SY8106A_REG_VOUT1_SEL, |
110 | val: vsel | SY8106A_GO_BIT); |
111 | if (error) |
112 | return error; |
113 | } |
114 | |
115 | /* Probe regulator */ |
116 | rdev = devm_regulator_register(dev: &i2c->dev, regulator_desc: &sy8106a_reg, config: &config); |
117 | if (IS_ERR(ptr: rdev)) { |
118 | error = PTR_ERR(ptr: rdev); |
119 | dev_err(&i2c->dev, "Failed to register SY8106A regulator: %d\n" , error); |
120 | return error; |
121 | } |
122 | |
123 | return 0; |
124 | } |
125 | |
126 | static const struct of_device_id sy8106a_i2c_of_match[] = { |
127 | { .compatible = "silergy,sy8106a" }, |
128 | { }, |
129 | }; |
130 | MODULE_DEVICE_TABLE(of, sy8106a_i2c_of_match); |
131 | |
132 | static const struct i2c_device_id sy8106a_i2c_id[] = { |
133 | { "sy8106a" , 0 }, |
134 | { }, |
135 | }; |
136 | MODULE_DEVICE_TABLE(i2c, sy8106a_i2c_id); |
137 | |
138 | static struct i2c_driver sy8106a_regulator_driver = { |
139 | .driver = { |
140 | .name = "sy8106a" , |
141 | .probe_type = PROBE_PREFER_ASYNCHRONOUS, |
142 | .of_match_table = sy8106a_i2c_of_match, |
143 | }, |
144 | .probe = sy8106a_i2c_probe, |
145 | .id_table = sy8106a_i2c_id, |
146 | }; |
147 | |
148 | module_i2c_driver(sy8106a_regulator_driver); |
149 | |
150 | MODULE_AUTHOR("Ondřej Jirman <megous@megous.com>" ); |
151 | MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>" ); |
152 | MODULE_DESCRIPTION("Regulator device driver for Silergy SY8106A" ); |
153 | MODULE_LICENSE("GPL" ); |
154 | |