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Diffstat (limited to 'drivers/peci/core.c')
-rw-r--r--drivers/peci/core.c236
1 files changed, 236 insertions, 0 deletions
diff --git a/drivers/peci/core.c b/drivers/peci/core.c
new file mode 100644
index 000000000000..9c8cf07e51c7
--- /dev/null
+++ b/drivers/peci/core.c
@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (c) 2018-2021 Intel Corporation
+
+#include <linux/bug.h>
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/idr.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/peci.h>
+#include <linux/pm_runtime.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+
+#include "internal.h"
+
+static DEFINE_IDA(peci_controller_ida);
+
+static void peci_controller_dev_release(struct device *dev)
+{
+ struct peci_controller *controller = to_peci_controller(dev);
+
+ mutex_destroy(&controller->bus_lock);
+ ida_free(&peci_controller_ida, controller->id);
+ kfree(controller);
+}
+
+struct device_type peci_controller_type = {
+ .release = peci_controller_dev_release,
+};
+
+int peci_controller_scan_devices(struct peci_controller *controller)
+{
+ int ret;
+ u8 addr;
+
+ for (addr = PECI_BASE_ADDR; addr < PECI_BASE_ADDR + PECI_DEVICE_NUM_MAX; addr++) {
+ ret = peci_device_create(controller, addr);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static struct peci_controller *peci_controller_alloc(struct device *dev,
+ struct peci_controller_ops *ops)
+{
+ struct peci_controller *controller;
+ int ret;
+
+ if (!ops->xfer)
+ return ERR_PTR(-EINVAL);
+
+ controller = kzalloc(sizeof(*controller), GFP_KERNEL);
+ if (!controller)
+ return ERR_PTR(-ENOMEM);
+
+ ret = ida_alloc_max(&peci_controller_ida, U8_MAX, GFP_KERNEL);
+ if (ret < 0)
+ goto err;
+ controller->id = ret;
+
+ controller->ops = ops;
+
+ controller->dev.parent = dev;
+ controller->dev.bus = &peci_bus_type;
+ controller->dev.type = &peci_controller_type;
+
+ device_initialize(&controller->dev);
+
+ mutex_init(&controller->bus_lock);
+
+ return controller;
+
+err:
+ kfree(controller);
+ return ERR_PTR(ret);
+}
+
+static int unregister_child(struct device *dev, void *dummy)
+{
+ peci_device_destroy(to_peci_device(dev));
+
+ return 0;
+}
+
+static void unregister_controller(void *_controller)
+{
+ struct peci_controller *controller = _controller;
+
+ /*
+ * Detach any active PECI devices. This can't fail, thus we do not
+ * check the returned value.
+ */
+ device_for_each_child_reverse(&controller->dev, NULL, unregister_child);
+
+ device_unregister(&controller->dev);
+
+ fwnode_handle_put(controller->dev.fwnode);
+
+ pm_runtime_disable(&controller->dev);
+}
+
+/**
+ * devm_peci_controller_add() - add PECI controller
+ * @dev: device for devm operations
+ * @ops: pointer to controller specific methods
+ *
+ * In final stage of its probe(), peci_controller driver calls
+ * devm_peci_controller_add() to register itself with the PECI bus.
+ *
+ * Return: Pointer to the newly allocated controller or ERR_PTR() in case of failure.
+ */
+struct peci_controller *devm_peci_controller_add(struct device *dev,
+ struct peci_controller_ops *ops)
+{
+ struct peci_controller *controller;
+ int ret;
+
+ controller = peci_controller_alloc(dev, ops);
+ if (IS_ERR(controller))
+ return controller;
+
+ ret = dev_set_name(&controller->dev, "peci-%d", controller->id);
+ if (ret)
+ goto err_put;
+
+ pm_runtime_no_callbacks(&controller->dev);
+ pm_suspend_ignore_children(&controller->dev, true);
+ pm_runtime_enable(&controller->dev);
+
+ device_set_node(&controller->dev, fwnode_handle_get(dev_fwnode(dev)));
+
+ ret = device_add(&controller->dev);
+ if (ret)
+ goto err_fwnode;
+
+ ret = devm_add_action_or_reset(dev, unregister_controller, controller);
+ if (ret)
+ return ERR_PTR(ret);
+
+ /*
+ * Ignoring retval since failures during scan are non-critical for
+ * controller itself.
+ */
+ peci_controller_scan_devices(controller);
+
+ return controller;
+
+err_fwnode:
+ fwnode_handle_put(controller->dev.fwnode);
+
+ pm_runtime_disable(&controller->dev);
+
+err_put:
+ put_device(&controller->dev);
+
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_NS_GPL(devm_peci_controller_add, PECI);
+
+static const struct peci_device_id *
+peci_bus_match_device_id(const struct peci_device_id *id, struct peci_device *device)
+{
+ while (id->family != 0) {
+ if (id->family == device->info.family &&
+ id->model == device->info.model)
+ return id;
+ id++;
+ }
+
+ return NULL;
+}
+
+static int peci_bus_device_match(struct device *dev, struct device_driver *drv)
+{
+ struct peci_device *device = to_peci_device(dev);
+ struct peci_driver *peci_drv = to_peci_driver(drv);
+
+ if (dev->type != &peci_device_type)
+ return 0;
+
+ return !!peci_bus_match_device_id(peci_drv->id_table, device);
+}
+
+static int peci_bus_device_probe(struct device *dev)
+{
+ struct peci_device *device = to_peci_device(dev);
+ struct peci_driver *driver = to_peci_driver(dev->driver);
+
+ return driver->probe(device, peci_bus_match_device_id(driver->id_table, device));
+}
+
+static void peci_bus_device_remove(struct device *dev)
+{
+ struct peci_device *device = to_peci_device(dev);
+ struct peci_driver *driver = to_peci_driver(dev->driver);
+
+ if (driver->remove)
+ driver->remove(device);
+}
+
+struct bus_type peci_bus_type = {
+ .name = "peci",
+ .match = peci_bus_device_match,
+ .probe = peci_bus_device_probe,
+ .remove = peci_bus_device_remove,
+ .bus_groups = peci_bus_groups,
+};
+
+static int __init peci_init(void)
+{
+ int ret;
+
+ ret = bus_register(&peci_bus_type);
+ if (ret < 0) {
+ pr_err("peci: failed to register PECI bus type!\n");
+ return ret;
+ }
+
+ return 0;
+}
+module_init(peci_init);
+
+static void __exit peci_exit(void)
+{
+ bus_unregister(&peci_bus_type);
+}
+module_exit(peci_exit);
+
+MODULE_AUTHOR("Jason M Bills <jason.m.bills@linux.intel.com>");
+MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>");
+MODULE_AUTHOR("Iwona Winiarska <iwona.winiarska@intel.com>");
+MODULE_DESCRIPTION("PECI bus core module");
+MODULE_LICENSE("GPL");