pse_regulator.c

  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
 15struct 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
 21static 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
 26static int
 27pse_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
 40static int
 41pse_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
 54static int
 55pse_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
 65static int
 66pse_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
 86static 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
 93static int
 94pse_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
137static const __maybe_unused struct of_device_id pse_reg_of_match[] = {
138	{ .compatible = "podl-pse-regulator", },
139	{ },
140};
141MODULE_DEVICE_TABLE(of, pse_reg_of_match);
142
143static 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};
150module_platform_driver(pse_reg_driver);
151
152MODULE_AUTHOR("Oleksij Rempel <kernel@pengutronix.de>");
153MODULE_DESCRIPTION("regulator based Ethernet Power Sourcing Equipment");
154MODULE_LICENSE("GPL v2");
155MODULE_ALIAS("platform:pse-regulator");