1 // SPDX-License-Identifier: GPL-2.0-only
2 //
3 // Driver for the regulator based Ethernet Power Sourcing Equipment, without
4 // auto classification support.
5 //
6 // Copyright (c) 2022 Pengutronix, Oleksij Rempel <[email protected]>
7 //
8
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/platform_device.h>
12 #include <linux/pse-pd/pse.h>
13 #include <linux/regulator/consumer.h>
14
15 struct pse_reg_priv {
16 struct pse_controller_dev pcdev;
17 struct regulator *ps; /*power source */
18 enum ethtool_podl_pse_admin_state admin_state;
19 };
20
to_pse_reg(struct pse_controller_dev * pcdev)21 static struct pse_reg_priv *to_pse_reg(struct pse_controller_dev *pcdev)
22 {
23 return container_of(pcdev, struct pse_reg_priv, pcdev);
24 }
25
26 static int
pse_reg_pi_enable(struct pse_controller_dev * pcdev,int id)27 pse_reg_pi_enable(struct pse_controller_dev *pcdev, int id)
28 {
29 struct pse_reg_priv *priv = to_pse_reg(pcdev);
30 int ret;
31
32 ret = regulator_enable(priv->ps);
33 if (ret)
34 return ret;
35
36 priv->admin_state = ETHTOOL_PODL_PSE_ADMIN_STATE_ENABLED;
37 return 0;
38 }
39
40 static int
pse_reg_pi_disable(struct pse_controller_dev * pcdev,int id)41 pse_reg_pi_disable(struct pse_controller_dev *pcdev, int id)
42 {
43 struct pse_reg_priv *priv = to_pse_reg(pcdev);
44 int ret;
45
46 ret = regulator_disable(priv->ps);
47 if (ret)
48 return ret;
49
50 priv->admin_state = ETHTOOL_PODL_PSE_ADMIN_STATE_DISABLED;
51 return 0;
52 }
53
54 static int
pse_reg_pi_get_admin_state(struct pse_controller_dev * pcdev,int id,struct pse_admin_state * admin_state)55 pse_reg_pi_get_admin_state(struct pse_controller_dev *pcdev, int id,
56 struct pse_admin_state *admin_state)
57 {
58 struct pse_reg_priv *priv = to_pse_reg(pcdev);
59
60 admin_state->podl_admin_state = priv->admin_state;
61
62 return 0;
63 }
64
65 static int
pse_reg_pi_get_pw_status(struct pse_controller_dev * pcdev,int id,struct pse_pw_status * pw_status)66 pse_reg_pi_get_pw_status(struct pse_controller_dev *pcdev, int id,
67 struct pse_pw_status *pw_status)
68 {
69 struct pse_reg_priv *priv = to_pse_reg(pcdev);
70 int ret;
71
72 ret = regulator_is_enabled(priv->ps);
73 if (ret < 0)
74 return ret;
75
76 if (!ret)
77 pw_status->podl_pw_status =
78 ETHTOOL_PODL_PSE_PW_D_STATUS_DISABLED;
79 else
80 pw_status->podl_pw_status =
81 ETHTOOL_PODL_PSE_PW_D_STATUS_DELIVERING;
82
83 return 0;
84 }
85
86 static const struct pse_controller_ops pse_reg_ops = {
87 .pi_get_admin_state = pse_reg_pi_get_admin_state,
88 .pi_get_pw_status = pse_reg_pi_get_pw_status,
89 .pi_enable = pse_reg_pi_enable,
90 .pi_disable = pse_reg_pi_disable,
91 };
92
93 static int
pse_reg_probe(struct platform_device * pdev)94 pse_reg_probe(struct platform_device *pdev)
95 {
96 struct device *dev = &pdev->dev;
97 struct pse_reg_priv *priv;
98 int ret;
99
100 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
101 if (!priv)
102 return -ENOMEM;
103
104 if (!pdev->dev.of_node)
105 return -ENOENT;
106
107 priv->ps = devm_regulator_get_exclusive(dev, "pse");
108 if (IS_ERR(priv->ps))
109 return dev_err_probe(dev, PTR_ERR(priv->ps),
110 "failed to get PSE regulator.\n");
111
112 platform_set_drvdata(pdev, priv);
113
114 ret = regulator_is_enabled(priv->ps);
115 if (ret < 0)
116 return ret;
117
118 if (ret)
119 priv->admin_state = ETHTOOL_PODL_PSE_ADMIN_STATE_ENABLED;
120 else
121 priv->admin_state = ETHTOOL_PODL_PSE_ADMIN_STATE_DISABLED;
122
123 priv->pcdev.owner = THIS_MODULE;
124 priv->pcdev.ops = &pse_reg_ops;
125 priv->pcdev.dev = dev;
126 priv->pcdev.types = ETHTOOL_PSE_PODL;
127 ret = devm_pse_controller_register(dev, &priv->pcdev);
128 if (ret) {
129 dev_err(dev, "failed to register PSE controller (%pe)\n",
130 ERR_PTR(ret));
131 return ret;
132 }
133
134 return 0;
135 }
136
137 static const __maybe_unused struct of_device_id pse_reg_of_match[] = {
138 { .compatible = "podl-pse-regulator", },
139 { },
140 };
141 MODULE_DEVICE_TABLE(of, pse_reg_of_match);
142
143 static struct platform_driver pse_reg_driver = {
144 .probe = pse_reg_probe,
145 .driver = {
146 .name = "PSE regulator",
147 .of_match_table = of_match_ptr(pse_reg_of_match),
148 },
149 };
150 module_platform_driver(pse_reg_driver);
151
152 MODULE_AUTHOR("Oleksij Rempel <[email protected]>");
153 MODULE_DESCRIPTION("regulator based Ethernet Power Sourcing Equipment");
154 MODULE_LICENSE("GPL v2");
155 MODULE_ALIAS("platform:pse-regulator");
156