1 files changed, 94 insertions, 0 deletions
diff --git a/drivers/staging/uwb/umc-dev.c b/drivers/staging/uwb/umc-dev.c
new file mode 100644
index 000000000000..0c71caae00be
--- /dev/null
+++ b/drivers/staging/uwb/umc-dev.c
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * UWB Multi-interface Controller device management.
+ *
+ * Copyright (C) 2007 Cambridge Silicon Radio Ltd.
+ */
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include "include/umc.h"
+
+static void umc_device_release(struct device *dev)
+{
+	struct umc_dev *umc = to_umc_dev(dev);
+
+	kfree(umc);
+}
+
+/**
+ * umc_device_create - allocate a child UMC device
+ * @parent: parent of the new UMC device.
+ * @n:      index of the new device.
+ *
+ * The new UMC device will have a bus ID of the parent with '-n'
+ * appended.
+ */
+struct umc_dev *umc_device_create(struct device *parent, int n)
+{
+	struct umc_dev *umc;
+
+	umc = kzalloc(sizeof(struct umc_dev), GFP_KERNEL);
+	if (umc) {
+		dev_set_name(&umc->dev, "%s-%d", dev_name(parent), n);
+		umc->dev.parent  = parent;
+		umc->dev.bus     = &umc_bus_type;
+		umc->dev.release = umc_device_release;
+
+		umc->dev.dma_mask = parent->dma_mask;
+	}
+	return umc;
+}
+EXPORT_SYMBOL_GPL(umc_device_create);
+
+/**
+ * umc_device_register - register a UMC device
+ * @umc: pointer to the UMC device
+ *
+ * The memory resource for the UMC device is acquired and the device
+ * registered with the system.
+ */
+int umc_device_register(struct umc_dev *umc)
+{
+	int err;
+
+	err = request_resource(umc->resource.parent, &umc->resource);
+	if (err < 0) {
+		dev_err(&umc->dev, "can't allocate resource range %pR: %d\n",
+			&umc->resource, err);
+		goto error_request_resource;
+	}
+
+	err = device_register(&umc->dev);
+	if (err < 0)
+		goto error_device_register;
+	return 0;
+
+error_device_register:
+	put_device(&umc->dev);
+	release_resource(&umc->resource);
+error_request_resource:
+	return err;
+}
+EXPORT_SYMBOL_GPL(umc_device_register);
+
+/**
+ * umc_device_unregister - unregister a UMC device
+ * @umc: pointer to the UMC device
+ *
+ * First we unregister the device, make sure the driver can do it's
+ * resource release thing and then we try to release any left over
+ * resources. We take a ref to the device, to make sure it doesn't
+ * disappear under our feet.
+ */
+void umc_device_unregister(struct umc_dev *umc)
+{
+	struct device *dev;
+	if (!umc)
+		return;
+	dev = get_device(&umc->dev);
+	device_unregister(&umc->dev);
+	release_resource(&umc->resource);
+	put_device(dev);
+}
+EXPORT_SYMBOL_GPL(umc_device_unregister);