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-rw-r--r--drivers/net/pse-pd/pse_core.c314
1 files changed, 314 insertions, 0 deletions
diff --git a/drivers/net/pse-pd/pse_core.c b/drivers/net/pse-pd/pse_core.c
new file mode 100644
index 000000000..146b81f08
--- /dev/null
+++ b/drivers/net/pse-pd/pse_core.c
@@ -0,0 +1,314 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// Framework for Ethernet Power Sourcing Equipment
+//
+// Copyright (c) 2022 Pengutronix, Oleksij Rempel <kernel@pengutronix.de>
+//
+
+#include <linux/device.h>
+#include <linux/of.h>
+#include <linux/pse-pd/pse.h>
+
+static DEFINE_MUTEX(pse_list_mutex);
+static LIST_HEAD(pse_controller_list);
+
+/**
+ * struct pse_control - a PSE control
+ * @pcdev: a pointer to the PSE controller device
+ * this PSE control belongs to
+ * @list: list entry for the pcdev's PSE controller list
+ * @id: ID of the PSE line in the PSE controller device
+ * @refcnt: Number of gets of this pse_control
+ */
+struct pse_control {
+ struct pse_controller_dev *pcdev;
+ struct list_head list;
+ unsigned int id;
+ struct kref refcnt;
+};
+
+/**
+ * of_pse_zero_xlate - dummy function for controllers with one only control
+ * @pcdev: a pointer to the PSE controller device
+ * @pse_spec: PSE line specifier as found in the device tree
+ *
+ * This static translation function is used by default if of_xlate in
+ * :c:type:`pse_controller_dev` is not set. It is useful for all PSE
+ * controllers with #pse-cells = <0>.
+ */
+static int of_pse_zero_xlate(struct pse_controller_dev *pcdev,
+ const struct of_phandle_args *pse_spec)
+{
+ return 0;
+}
+
+/**
+ * of_pse_simple_xlate - translate pse_spec to the PSE line number
+ * @pcdev: a pointer to the PSE controller device
+ * @pse_spec: PSE line specifier as found in the device tree
+ *
+ * This static translation function is used by default if of_xlate in
+ * :c:type:`pse_controller_dev` is not set. It is useful for all PSE
+ * controllers with 1:1 mapping, where PSE lines can be indexed by number
+ * without gaps.
+ */
+static int of_pse_simple_xlate(struct pse_controller_dev *pcdev,
+ const struct of_phandle_args *pse_spec)
+{
+ if (pse_spec->args[0] >= pcdev->nr_lines)
+ return -EINVAL;
+
+ return pse_spec->args[0];
+}
+
+/**
+ * pse_controller_register - register a PSE controller device
+ * @pcdev: a pointer to the initialized PSE controller device
+ */
+int pse_controller_register(struct pse_controller_dev *pcdev)
+{
+ if (!pcdev->of_xlate) {
+ if (pcdev->of_pse_n_cells == 0)
+ pcdev->of_xlate = of_pse_zero_xlate;
+ else if (pcdev->of_pse_n_cells == 1)
+ pcdev->of_xlate = of_pse_simple_xlate;
+ }
+
+ mutex_init(&pcdev->lock);
+ INIT_LIST_HEAD(&pcdev->pse_control_head);
+
+ mutex_lock(&pse_list_mutex);
+ list_add(&pcdev->list, &pse_controller_list);
+ mutex_unlock(&pse_list_mutex);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pse_controller_register);
+
+/**
+ * pse_controller_unregister - unregister a PSE controller device
+ * @pcdev: a pointer to the PSE controller device
+ */
+void pse_controller_unregister(struct pse_controller_dev *pcdev)
+{
+ mutex_lock(&pse_list_mutex);
+ list_del(&pcdev->list);
+ mutex_unlock(&pse_list_mutex);
+}
+EXPORT_SYMBOL_GPL(pse_controller_unregister);
+
+static void devm_pse_controller_release(struct device *dev, void *res)
+{
+ pse_controller_unregister(*(struct pse_controller_dev **)res);
+}
+
+/**
+ * devm_pse_controller_register - resource managed pse_controller_register()
+ * @dev: device that is registering this PSE controller
+ * @pcdev: a pointer to the initialized PSE controller device
+ *
+ * Managed pse_controller_register(). For PSE controllers registered by
+ * this function, pse_controller_unregister() is automatically called on
+ * driver detach. See pse_controller_register() for more information.
+ */
+int devm_pse_controller_register(struct device *dev,
+ struct pse_controller_dev *pcdev)
+{
+ struct pse_controller_dev **pcdevp;
+ int ret;
+
+ pcdevp = devres_alloc(devm_pse_controller_release, sizeof(*pcdevp),
+ GFP_KERNEL);
+ if (!pcdevp)
+ return -ENOMEM;
+
+ ret = pse_controller_register(pcdev);
+ if (ret) {
+ devres_free(pcdevp);
+ return ret;
+ }
+
+ *pcdevp = pcdev;
+ devres_add(dev, pcdevp);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(devm_pse_controller_register);
+
+/* PSE control section */
+
+static void __pse_control_release(struct kref *kref)
+{
+ struct pse_control *psec = container_of(kref, struct pse_control,
+ refcnt);
+
+ lockdep_assert_held(&pse_list_mutex);
+
+ module_put(psec->pcdev->owner);
+
+ list_del(&psec->list);
+ kfree(psec);
+}
+
+static void __pse_control_put_internal(struct pse_control *psec)
+{
+ lockdep_assert_held(&pse_list_mutex);
+
+ kref_put(&psec->refcnt, __pse_control_release);
+}
+
+/**
+ * pse_control_put - free the PSE control
+ * @psec: PSE control pointer
+ */
+void pse_control_put(struct pse_control *psec)
+{
+ if (IS_ERR_OR_NULL(psec))
+ return;
+
+ mutex_lock(&pse_list_mutex);
+ __pse_control_put_internal(psec);
+ mutex_unlock(&pse_list_mutex);
+}
+EXPORT_SYMBOL_GPL(pse_control_put);
+
+static struct pse_control *
+pse_control_get_internal(struct pse_controller_dev *pcdev, unsigned int index)
+{
+ struct pse_control *psec;
+
+ lockdep_assert_held(&pse_list_mutex);
+
+ list_for_each_entry(psec, &pcdev->pse_control_head, list) {
+ if (psec->id == index) {
+ kref_get(&psec->refcnt);
+ return psec;
+ }
+ }
+
+ psec = kzalloc(sizeof(*psec), GFP_KERNEL);
+ if (!psec)
+ return ERR_PTR(-ENOMEM);
+
+ if (!try_module_get(pcdev->owner)) {
+ kfree(psec);
+ return ERR_PTR(-ENODEV);
+ }
+
+ psec->pcdev = pcdev;
+ list_add(&psec->list, &pcdev->pse_control_head);
+ psec->id = index;
+ kref_init(&psec->refcnt);
+
+ return psec;
+}
+
+struct pse_control *
+of_pse_control_get(struct device_node *node)
+{
+ struct pse_controller_dev *r, *pcdev;
+ struct of_phandle_args args;
+ struct pse_control *psec;
+ int psec_id;
+ int ret;
+
+ if (!node)
+ return ERR_PTR(-EINVAL);
+
+ ret = of_parse_phandle_with_args(node, "pses", "#pse-cells", 0, &args);
+ if (ret)
+ return ERR_PTR(ret);
+
+ mutex_lock(&pse_list_mutex);
+ pcdev = NULL;
+ list_for_each_entry(r, &pse_controller_list, list) {
+ if (args.np == r->dev->of_node) {
+ pcdev = r;
+ break;
+ }
+ }
+
+ if (!pcdev) {
+ psec = ERR_PTR(-EPROBE_DEFER);
+ goto out;
+ }
+
+ if (WARN_ON(args.args_count != pcdev->of_pse_n_cells)) {
+ psec = ERR_PTR(-EINVAL);
+ goto out;
+ }
+
+ psec_id = pcdev->of_xlate(pcdev, &args);
+ if (psec_id < 0) {
+ psec = ERR_PTR(psec_id);
+ goto out;
+ }
+
+ /* pse_list_mutex also protects the pcdev's pse_control list */
+ psec = pse_control_get_internal(pcdev, psec_id);
+
+out:
+ mutex_unlock(&pse_list_mutex);
+ of_node_put(args.np);
+
+ return psec;
+}
+EXPORT_SYMBOL_GPL(of_pse_control_get);
+
+/**
+ * pse_ethtool_get_status - get status of PSE control
+ * @psec: PSE control pointer
+ * @extack: extack for reporting useful error messages
+ * @status: struct to store PSE status
+ */
+int pse_ethtool_get_status(struct pse_control *psec,
+ struct netlink_ext_ack *extack,
+ struct pse_control_status *status)
+{
+ const struct pse_controller_ops *ops;
+ int err;
+
+ ops = psec->pcdev->ops;
+
+ if (!ops->ethtool_get_status) {
+ NL_SET_ERR_MSG(extack,
+ "PSE driver does not support status report");
+ return -EOPNOTSUPP;
+ }
+
+ mutex_lock(&psec->pcdev->lock);
+ err = ops->ethtool_get_status(psec->pcdev, psec->id, extack, status);
+ mutex_unlock(&psec->pcdev->lock);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(pse_ethtool_get_status);
+
+/**
+ * pse_ethtool_set_config - set PSE control configuration
+ * @psec: PSE control pointer
+ * @extack: extack for reporting useful error messages
+ * @config: Configuration of the test to run
+ */
+int pse_ethtool_set_config(struct pse_control *psec,
+ struct netlink_ext_ack *extack,
+ const struct pse_control_config *config)
+{
+ const struct pse_controller_ops *ops;
+ int err;
+
+ ops = psec->pcdev->ops;
+
+ if (!ops->ethtool_set_config) {
+ NL_SET_ERR_MSG(extack,
+ "PSE driver does not configuration");
+ return -EOPNOTSUPP;
+ }
+
+ mutex_lock(&psec->pcdev->lock);
+ err = ops->ethtool_set_config(psec->pcdev, psec->id, extack, config);
+ mutex_unlock(&psec->pcdev->lock);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(pse_ethtool_set_config);