[PATCH net-next v6 7/7] net: pse-pd: add regulator based PSE driver

From: Oleksij Rempel
Date: Wed Sep 21 2022 - 08:48:18 EST


Add generic, regulator based PSE driver to support simple Power Sourcing
Equipment without automatic classification support.

This driver was tested on 10Bast-T1L switch with regulator based PoDL PSE.

Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
---
changes v5:
- use dev_err_probe on devm_regulator_get_exclusive() error
- add __maybe_unused to the of_device_id
changes v4:
- rename to pse_regulator
changes v2:
- add regulator_enable test to the probe
- migrate to the new PSE ethtool API
---
drivers/net/pse-pd/Kconfig | 11 +++
drivers/net/pse-pd/Makefile | 2 +
drivers/net/pse-pd/pse_regulator.c | 147 +++++++++++++++++++++++++++++
3 files changed, 160 insertions(+)
create mode 100644 drivers/net/pse-pd/pse_regulator.c

diff --git a/drivers/net/pse-pd/Kconfig b/drivers/net/pse-pd/Kconfig
index 49c7f0bcff52..73d163704068 100644
--- a/drivers/net/pse-pd/Kconfig
+++ b/drivers/net/pse-pd/Kconfig
@@ -9,3 +9,14 @@ menuconfig PSE_CONTROLLER
Generic Power Sourcing Equipment Controller support.

If unsure, say no.
+
+if PSE_CONTROLLER
+
+config PSE_REGULATOR
+ tristate "Regulator based PSE controller"
+ help
+ This module provides support for simple regulator based Ethernet Power
+ Sourcing Equipment without automatic classification support. For
+ example for basic implementation of PoDL (802.3bu) specification.
+
+endif
diff --git a/drivers/net/pse-pd/Makefile b/drivers/net/pse-pd/Makefile
index cfa780c7801d..1b8aa4c70f0b 100644
--- a/drivers/net/pse-pd/Makefile
+++ b/drivers/net/pse-pd/Makefile
@@ -2,3 +2,5 @@
# Makefile for Linux PSE drivers

obj-$(CONFIG_PSE_CONTROLLER) += pse_core.o
+
+obj-$(CONFIG_PSE_REGULATOR) += pse_regulator.o
diff --git a/drivers/net/pse-pd/pse_regulator.c b/drivers/net/pse-pd/pse_regulator.c
new file mode 100644
index 000000000000..e2bf8306ca90
--- /dev/null
+++ b/drivers/net/pse-pd/pse_regulator.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// Driver for the regulator based Ethernet Power Sourcing Equipment, without
+// auto classification support.
+//
+// Copyright (c) 2022 Pengutronix, Oleksij Rempel <kernel@xxxxxxxxxxxxxx>
+//
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pse-pd/pse.h>
+#include <linux/regulator/consumer.h>
+
+struct pse_reg_priv {
+ struct pse_controller_dev pcdev;
+ struct regulator *ps; /*power source */
+ enum ethtool_podl_pse_admin_state admin_state;
+};
+
+static struct pse_reg_priv *to_pse_reg(struct pse_controller_dev *pcdev)
+{
+ return container_of(pcdev, struct pse_reg_priv, pcdev);
+}
+
+static int
+pse_reg_ethtool_set_config(struct pse_controller_dev *pcdev, unsigned long id,
+ struct netlink_ext_ack *extack,
+ const struct pse_control_config *config)
+{
+ struct pse_reg_priv *priv = to_pse_reg(pcdev);
+ int ret;
+
+ if (priv->admin_state == config->admin_cotrol)
+ return 0;
+
+ switch (config->admin_cotrol) {
+ case ETHTOOL_PODL_PSE_ADMIN_STATE_ENABLED:
+ ret = regulator_enable(priv->ps);
+ break;
+ case ETHTOOL_PODL_PSE_ADMIN_STATE_DISABLED:
+ ret = regulator_disable(priv->ps);
+ break;
+ default:
+ dev_err(pcdev->dev, "Unknown admin state %i\n",
+ config->admin_cotrol);
+ ret = -ENOTSUPP;
+ }
+
+ if (ret)
+ return ret;
+
+ priv->admin_state = config->admin_cotrol;
+
+ return 0;
+}
+
+static int
+pse_reg_ethtool_get_status(struct pse_controller_dev *pcdev, unsigned long id,
+ struct netlink_ext_ack *extack,
+ struct pse_control_status *status)
+{
+ struct pse_reg_priv *priv = to_pse_reg(pcdev);
+ int ret;
+
+ ret = regulator_is_enabled(priv->ps);
+ if (ret < 0)
+ return ret;
+
+ if (!ret)
+ status->podl_pw_status = ETHTOOL_PODL_PSE_PW_D_STATUS_DISABLED;
+ else
+ status->podl_pw_status =
+ ETHTOOL_PODL_PSE_PW_D_STATUS_DELIVERING;
+
+ status->podl_admin_state = priv->admin_state;
+
+ return 0;
+}
+
+static const struct pse_controller_ops pse_reg_ops = {
+ .ethtool_get_status = pse_reg_ethtool_get_status,
+ .ethtool_set_config = pse_reg_ethtool_set_config,
+};
+
+static int
+pse_reg_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pse_reg_priv *priv;
+ int ret;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ if (!pdev->dev.of_node)
+ return -ENOENT;
+
+ priv->ps = devm_regulator_get_exclusive(dev, "pse");
+ if (IS_ERR(priv->ps))
+ return dev_err_probe(dev, PTR_ERR(priv->ps),
+ "failed to get PSE regulator.\n");
+
+ platform_set_drvdata(pdev, priv);
+
+ ret = regulator_is_enabled(priv->ps);
+ if (ret < 0)
+ return ret;
+
+ if (ret)
+ priv->admin_state = ETHTOOL_PODL_PSE_ADMIN_STATE_ENABLED;
+ else
+ priv->admin_state = ETHTOOL_PODL_PSE_ADMIN_STATE_DISABLED;
+
+ priv->pcdev.owner = THIS_MODULE;
+ priv->pcdev.ops = &pse_reg_ops;
+ priv->pcdev.dev = dev;
+ ret = devm_pse_controller_register(dev, &priv->pcdev);
+ if (ret) {
+ dev_err(dev, "failed to register PSE controller (%pe)\n",
+ ERR_PTR(ret));
+ return ret;
+ }
+
+ return 0;
+}
+
+static const __maybe_unused struct of_device_id pse_reg_of_match[] = {
+ { .compatible = "podl-pse-regulator", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, pse_reg_of_match);
+
+static struct platform_driver pse_reg_driver = {
+ .probe = pse_reg_probe,
+ .driver = {
+ .name = "PSE regulator",
+ .of_match_table = of_match_ptr(pse_reg_of_match),
+ },
+};
+module_platform_driver(pse_reg_driver);
+
+MODULE_AUTHOR("Oleksij Rempel <kernel@xxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("regulator based Ethernet Power Sourcing Equipment");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:pse-regulator");
--
2.30.2