xref: /linux/drivers/net/pse-pd/pse_regulator.c (revision 89aa02edaa30e4327ebc8fca9b80795bbfd4ce9b)
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 <kernel@pengutronix.de>
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 
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
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
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
55 pse_reg_pi_is_enabled(struct pse_controller_dev *pcdev, int id)
56 {
57 	struct pse_reg_priv *priv = to_pse_reg(pcdev);
58 
59 	return regulator_is_enabled(priv->ps);
60 }
61 
62 static int
63 pse_reg_ethtool_get_status(struct pse_controller_dev *pcdev, unsigned long id,
64 			   struct netlink_ext_ack *extack,
65 			   struct pse_control_status *status)
66 {
67 	struct pse_reg_priv *priv = to_pse_reg(pcdev);
68 	int ret;
69 
70 	ret = regulator_is_enabled(priv->ps);
71 	if (ret < 0)
72 		return ret;
73 
74 	if (!ret)
75 		status->podl_pw_status = ETHTOOL_PODL_PSE_PW_D_STATUS_DISABLED;
76 	else
77 		status->podl_pw_status =
78 			ETHTOOL_PODL_PSE_PW_D_STATUS_DELIVERING;
79 
80 	status->podl_admin_state = priv->admin_state;
81 
82 	return 0;
83 }
84 
85 static const struct pse_controller_ops pse_reg_ops = {
86 	.ethtool_get_status = pse_reg_ethtool_get_status,
87 	.pi_enable = pse_reg_pi_enable,
88 	.pi_is_enabled = pse_reg_pi_is_enabled,
89 	.pi_disable = pse_reg_pi_disable,
90 };
91 
92 static int
93 pse_reg_probe(struct platform_device *pdev)
94 {
95 	struct device *dev = &pdev->dev;
96 	struct pse_reg_priv *priv;
97 	int ret;
98 
99 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
100 	if (!priv)
101 		return -ENOMEM;
102 
103 	if (!pdev->dev.of_node)
104 		return -ENOENT;
105 
106 	priv->ps = devm_regulator_get_exclusive(dev, "pse");
107 	if (IS_ERR(priv->ps))
108 		return dev_err_probe(dev, PTR_ERR(priv->ps),
109 				     "failed to get PSE regulator.\n");
110 
111 	platform_set_drvdata(pdev, priv);
112 
113 	ret = regulator_is_enabled(priv->ps);
114 	if (ret < 0)
115 		return ret;
116 
117 	if (ret)
118 		priv->admin_state = ETHTOOL_PODL_PSE_ADMIN_STATE_ENABLED;
119 	else
120 		priv->admin_state = ETHTOOL_PODL_PSE_ADMIN_STATE_DISABLED;
121 
122 	priv->pcdev.owner = THIS_MODULE;
123 	priv->pcdev.ops = &pse_reg_ops;
124 	priv->pcdev.dev = dev;
125 	priv->pcdev.types = ETHTOOL_PSE_PODL;
126 	ret = devm_pse_controller_register(dev, &priv->pcdev);
127 	if (ret) {
128 		dev_err(dev, "failed to register PSE controller (%pe)\n",
129 			ERR_PTR(ret));
130 		return ret;
131 	}
132 
133 	return 0;
134 }
135 
136 static const __maybe_unused struct of_device_id pse_reg_of_match[] = {
137 	{ .compatible = "podl-pse-regulator", },
138 	{ },
139 };
140 MODULE_DEVICE_TABLE(of, pse_reg_of_match);
141 
142 static struct platform_driver pse_reg_driver = {
143 	.probe		= pse_reg_probe,
144 	.driver		= {
145 		.name		= "PSE regulator",
146 		.of_match_table = of_match_ptr(pse_reg_of_match),
147 	},
148 };
149 module_platform_driver(pse_reg_driver);
150 
151 MODULE_AUTHOR("Oleksij Rempel <kernel@pengutronix.de>");
152 MODULE_DESCRIPTION("regulator based Ethernet Power Sourcing Equipment");
153 MODULE_LICENSE("GPL v2");
154 MODULE_ALIAS("platform:pse-regulator");
155