1 files changed, 517 insertions, 0 deletions
diff --git a/drivers/mcb/mcb-core.c b/drivers/mcb/mcb-core.c
new file mode 100644
index 000000000..a6b4ccc31
--- /dev/null
+++ b/drivers/mcb/mcb-core.c
@@ -0,0 +1,517 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * MEN Chameleon Bus.
+ *
+ * Copyright (C) 2013 MEN Mikroelektronik GmbH (www.men.de)
+ * Author: Johannes Thumshirn <johannes.thumshirn@men.de>
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/idr.h>
+#include <linux/mcb.h>
+
+static DEFINE_IDA(mcb_ida);
+
+static const struct mcb_device_id *mcb_match_id(const struct mcb_device_id *ids,
+						struct mcb_device *dev)
+{
+	if (ids) {
+		while (ids->device) {
+			if (ids->device == dev->id)
+				return ids;
+			ids++;
+		}
+	}
+
+	return NULL;
+}
+
+static int mcb_match(struct device *dev, struct device_driver *drv)
+{
+	struct mcb_driver *mdrv = to_mcb_driver(drv);
+	struct mcb_device *mdev = to_mcb_device(dev);
+	const struct mcb_device_id *found_id;
+
+	found_id = mcb_match_id(mdrv->id_table, mdev);
+	if (found_id)
+		return 1;
+
+	return 0;
+}
+
+static int mcb_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct mcb_device *mdev = to_mcb_device(dev);
+	int ret;
+
+	ret = add_uevent_var(env, "MODALIAS=mcb:16z%03d", mdev->id);
+	if (ret)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static int mcb_probe(struct device *dev)
+{
+	struct mcb_driver *mdrv = to_mcb_driver(dev->driver);
+	struct mcb_device *mdev = to_mcb_device(dev);
+	const struct mcb_device_id *found_id;
+	struct module *carrier_mod;
+	int ret;
+
+	found_id = mcb_match_id(mdrv->id_table, mdev);
+	if (!found_id)
+		return -ENODEV;
+
+	carrier_mod = mdev->dev.parent->driver->owner;
+	if (!try_module_get(carrier_mod))
+		return -EINVAL;
+
+	get_device(dev);
+	ret = mdrv->probe(mdev, found_id);
+	if (ret) {
+		module_put(carrier_mod);
+		put_device(dev);
+	}
+
+	return ret;
+}
+
+static void mcb_remove(struct device *dev)
+{
+	struct mcb_driver *mdrv = to_mcb_driver(dev->driver);
+	struct mcb_device *mdev = to_mcb_device(dev);
+	struct module *carrier_mod;
+
+	mdrv->remove(mdev);
+
+	carrier_mod = mdev->dev.parent->driver->owner;
+	module_put(carrier_mod);
+
+	put_device(&mdev->dev);
+}
+
+static void mcb_shutdown(struct device *dev)
+{
+	struct mcb_driver *mdrv = to_mcb_driver(dev->driver);
+	struct mcb_device *mdev = to_mcb_device(dev);
+
+	if (mdrv && mdrv->shutdown)
+		mdrv->shutdown(mdev);
+}
+
+static ssize_t revision_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct mcb_bus *bus = to_mcb_bus(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%d\n", bus->revision);
+}
+static DEVICE_ATTR_RO(revision);
+
+static ssize_t model_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct mcb_bus *bus = to_mcb_bus(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%c\n", bus->model);
+}
+static DEVICE_ATTR_RO(model);
+
+static ssize_t minor_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct mcb_bus *bus = to_mcb_bus(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%d\n", bus->minor);
+}
+static DEVICE_ATTR_RO(minor);
+
+static ssize_t name_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct mcb_bus *bus = to_mcb_bus(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%s\n", bus->name);
+}
+static DEVICE_ATTR_RO(name);
+
+static struct attribute *mcb_bus_attrs[] = {
+	&dev_attr_revision.attr,
+	&dev_attr_model.attr,
+	&dev_attr_minor.attr,
+	&dev_attr_name.attr,
+	NULL,
+};
+
+static const struct attribute_group mcb_carrier_group = {
+	.attrs = mcb_bus_attrs,
+};
+
+static const struct attribute_group *mcb_carrier_groups[] = {
+	&mcb_carrier_group,
+	NULL,
+};
+
+
+static struct bus_type mcb_bus_type = {
+	.name = "mcb",
+	.match = mcb_match,
+	.uevent = mcb_uevent,
+	.probe = mcb_probe,
+	.remove = mcb_remove,
+	.shutdown = mcb_shutdown,
+};
+
+static struct device_type mcb_carrier_device_type = {
+	.name = "mcb-carrier",
+	.groups = mcb_carrier_groups,
+};
+
+/**
+ * __mcb_register_driver() - Register a @mcb_driver at the system
+ * @drv: The @mcb_driver
+ * @owner: The @mcb_driver's module
+ * @mod_name: The name of the @mcb_driver's module
+ *
+ * Register a @mcb_driver at the system. Perform some sanity checks, if
+ * the .probe and .remove methods are provided by the driver.
+ */
+int __mcb_register_driver(struct mcb_driver *drv, struct module *owner,
+			const char *mod_name)
+{
+	if (!drv->probe || !drv->remove)
+		return -EINVAL;
+
+	drv->driver.owner = owner;
+	drv->driver.bus = &mcb_bus_type;
+	drv->driver.mod_name = mod_name;
+
+	return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_NS_GPL(__mcb_register_driver, MCB);
+
+/**
+ * mcb_unregister_driver() - Unregister a @mcb_driver from the system
+ * @drv: The @mcb_driver
+ *
+ * Unregister a @mcb_driver from the system.
+ */
+void mcb_unregister_driver(struct mcb_driver *drv)
+{
+	driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_NS_GPL(mcb_unregister_driver, MCB);
+
+static void mcb_release_dev(struct device *dev)
+{
+	struct mcb_device *mdev = to_mcb_device(dev);
+
+	mcb_bus_put(mdev->bus);
+	kfree(mdev);
+}
+
+/**
+ * mcb_device_register() - Register a mcb_device
+ * @bus: The @mcb_bus of the device
+ * @dev: The @mcb_device
+ *
+ * Register a specific @mcb_device at a @mcb_bus and the system itself.
+ */
+int mcb_device_register(struct mcb_bus *bus, struct mcb_device *dev)
+{
+	int ret;
+	int device_id;
+
+	device_initialize(&dev->dev);
+	mcb_bus_get(bus);
+	dev->dev.bus = &mcb_bus_type;
+	dev->dev.parent = bus->dev.parent;
+	dev->dev.release = mcb_release_dev;
+	dev->dma_dev = bus->carrier;
+
+	device_id = dev->id;
+	dev_set_name(&dev->dev, "mcb%d-16z%03d-%d:%d:%d",
+		bus->bus_nr, device_id, dev->inst, dev->group, dev->var);
+
+	ret = device_add(&dev->dev);
+	if (ret < 0) {
+		pr_err("Failed registering device 16z%03d on bus mcb%d (%d)\n",
+			device_id, bus->bus_nr, ret);
+		goto out;
+	}
+
+	return 0;
+
+out:
+	put_device(&dev->dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_NS_GPL(mcb_device_register, MCB);
+
+static void mcb_free_bus(struct device *dev)
+{
+	struct mcb_bus *bus = to_mcb_bus(dev);
+
+	put_device(bus->carrier);
+	ida_free(&mcb_ida, bus->bus_nr);
+	kfree(bus);
+}
+
+/**
+ * mcb_alloc_bus() - Allocate a new @mcb_bus
+ *
+ * Allocate a new @mcb_bus.
+ */
+struct mcb_bus *mcb_alloc_bus(struct device *carrier)
+{
+	struct mcb_bus *bus;
+	int bus_nr;
+	int rc;
+
+	bus = kzalloc(sizeof(struct mcb_bus), GFP_KERNEL);
+	if (!bus)
+		return ERR_PTR(-ENOMEM);
+
+	bus_nr = ida_alloc(&mcb_ida, GFP_KERNEL);
+	if (bus_nr < 0) {
+		kfree(bus);
+		return ERR_PTR(bus_nr);
+	}
+
+	bus->bus_nr = bus_nr;
+	bus->carrier = get_device(carrier);
+
+	device_initialize(&bus->dev);
+	bus->dev.parent = carrier;
+	bus->dev.bus = &mcb_bus_type;
+	bus->dev.type = &mcb_carrier_device_type;
+	bus->dev.release = &mcb_free_bus;
+
+	dev_set_name(&bus->dev, "mcb:%d", bus_nr);
+	rc = device_add(&bus->dev);
+	if (rc)
+		goto err_put;
+
+	return bus;
+
+err_put:
+	put_device(&bus->dev);
+	return ERR_PTR(rc);
+}
+EXPORT_SYMBOL_NS_GPL(mcb_alloc_bus, MCB);
+
+static int __mcb_devices_unregister(struct device *dev, void *data)
+{
+	device_unregister(dev);
+	return 0;
+}
+
+static void mcb_devices_unregister(struct mcb_bus *bus)
+{
+	bus_for_each_dev(&mcb_bus_type, NULL, NULL, __mcb_devices_unregister);
+}
+/**
+ * mcb_release_bus() - Free a @mcb_bus
+ * @bus: The @mcb_bus to release
+ *
+ * Release an allocated @mcb_bus from the system.
+ */
+void mcb_release_bus(struct mcb_bus *bus)
+{
+	mcb_devices_unregister(bus);
+}
+EXPORT_SYMBOL_NS_GPL(mcb_release_bus, MCB);
+
+/**
+ * mcb_bus_put() - Increment refcnt
+ * @bus: The @mcb_bus
+ *
+ * Get a @mcb_bus' ref
+ */
+struct mcb_bus *mcb_bus_get(struct mcb_bus *bus)
+{
+	if (bus)
+		get_device(&bus->dev);
+
+	return bus;
+}
+EXPORT_SYMBOL_NS_GPL(mcb_bus_get, MCB);
+
+/**
+ * mcb_bus_put() - Decrement refcnt
+ * @bus: The @mcb_bus
+ *
+ * Release a @mcb_bus' ref
+ */
+void mcb_bus_put(struct mcb_bus *bus)
+{
+	if (bus)
+		put_device(&bus->dev);
+}
+EXPORT_SYMBOL_NS_GPL(mcb_bus_put, MCB);
+
+/**
+ * mcb_alloc_dev() - Allocate a device
+ * @bus: The @mcb_bus the device is part of
+ *
+ * Allocate a @mcb_device and add bus.
+ */
+struct mcb_device *mcb_alloc_dev(struct mcb_bus *bus)
+{
+	struct mcb_device *dev;
+
+	dev = kzalloc(sizeof(struct mcb_device), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+
+	dev->bus = bus;
+
+	return dev;
+}
+EXPORT_SYMBOL_NS_GPL(mcb_alloc_dev, MCB);
+
+/**
+ * mcb_free_dev() - Free @mcb_device
+ * @dev: The device to free
+ *
+ * Free a @mcb_device
+ */
+void mcb_free_dev(struct mcb_device *dev)
+{
+	kfree(dev);
+}
+EXPORT_SYMBOL_NS_GPL(mcb_free_dev, MCB);
+
+static int __mcb_bus_add_devices(struct device *dev, void *data)
+{
+	int retval;
+
+	retval = device_attach(dev);
+	if (retval < 0) {
+		dev_err(dev, "Error adding device (%d)\n", retval);
+		return retval;
+	}
+
+	return 0;
+}
+
+/**
+ * mcb_bus_add_devices() - Add devices in the bus' internal device list
+ * @bus: The @mcb_bus we add the devices
+ *
+ * Add devices in the bus' internal device list to the system.
+ */
+void mcb_bus_add_devices(const struct mcb_bus *bus)
+{
+	bus_for_each_dev(&mcb_bus_type, NULL, NULL, __mcb_bus_add_devices);
+}
+EXPORT_SYMBOL_NS_GPL(mcb_bus_add_devices, MCB);
+
+/**
+ * mcb_get_resource() - get a resource for a mcb device
+ * @dev: the mcb device
+ * @type: the type of resource
+ */
+struct resource *mcb_get_resource(struct mcb_device *dev, unsigned int type)
+{
+	if (type == IORESOURCE_MEM)
+		return &dev->mem;
+	else if (type == IORESOURCE_IRQ)
+		return &dev->irq;
+	else
+		return NULL;
+}
+EXPORT_SYMBOL_NS_GPL(mcb_get_resource, MCB);
+
+/**
+ * mcb_request_mem() - Request memory
+ * @dev: The @mcb_device the memory is for
+ * @name: The name for the memory reference.
+ *
+ * Request memory for a @mcb_device. If @name is NULL the driver name will
+ * be used.
+ */
+struct resource *mcb_request_mem(struct mcb_device *dev, const char *name)
+{
+	struct resource *mem;
+	u32 size;
+
+	if (!name)
+		name = dev->dev.driver->name;
+
+	size = resource_size(&dev->mem);
+
+	mem = request_mem_region(dev->mem.start, size, name);
+	if (!mem)
+		return ERR_PTR(-EBUSY);
+
+	return mem;
+}
+EXPORT_SYMBOL_NS_GPL(mcb_request_mem, MCB);
+
+/**
+ * mcb_release_mem() - Release memory requested by device
+ * @dev: The @mcb_device that requested the memory
+ *
+ * Release memory that was prior requested via @mcb_request_mem().
+ */
+void mcb_release_mem(struct resource *mem)
+{
+	u32 size;
+
+	size = resource_size(mem);
+	release_mem_region(mem->start, size);
+}
+EXPORT_SYMBOL_NS_GPL(mcb_release_mem, MCB);
+
+static int __mcb_get_irq(struct mcb_device *dev)
+{
+	struct resource *irq;
+
+	irq = mcb_get_resource(dev, IORESOURCE_IRQ);
+
+	return irq->start;
+}
+
+/**
+ * mcb_get_irq() - Get device's IRQ number
+ * @dev: The @mcb_device the IRQ is for
+ *
+ * Get the IRQ number of a given @mcb_device.
+ */
+int mcb_get_irq(struct mcb_device *dev)
+{
+	struct mcb_bus *bus = dev->bus;
+
+	if (bus->get_irq)
+		return bus->get_irq(dev);
+
+	return __mcb_get_irq(dev);
+}
+EXPORT_SYMBOL_NS_GPL(mcb_get_irq, MCB);
+
+static int mcb_init(void)
+{
+	return bus_register(&mcb_bus_type);
+}
+
+static void mcb_exit(void)
+{
+	ida_destroy(&mcb_ida);
+	bus_unregister(&mcb_bus_type);
+}
+
+/* mcb must be initialized after PCI but before the chameleon drivers.
+ * That means we must use some initcall between subsys_initcall and
+ * device_initcall.
+ */
+fs_initcall(mcb_init);
+module_exit(mcb_exit);
+
+MODULE_DESCRIPTION("MEN Chameleon Bus Driver");
+MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
+MODULE_LICENSE("GPL v2");