Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 212 insertions, 0 deletions

diff --git a/drivers/uwb/umc-bus.c b/drivers/uwb/umc-bus.c
new file mode 100644
index 000000000..c85714051
--- /dev/null
+++ b/drivers/uwb/umc-bus.c
@@ -0,0 +1,212 @@
+/*
+ * Bus for UWB Multi-interface Controller capabilities.
+ *
+ * Copyright (C) 2007 Cambridge Silicon Radio Ltd.
+ *
+ * This file is released under the GNU GPL v2.
+ */
+#include <linux/kernel.h>
+#include <linux/sysfs.h>
+#include <linux/workqueue.h>
+#include <linux/module.h>
+#include <linux/uwb/umc.h>
+#include <linux/pci.h>
+
+static int umc_bus_pre_reset_helper(struct device *dev, void *data)
+{
+	int ret = 0;
+
+	if (dev->driver) {
+		struct umc_dev *umc = to_umc_dev(dev);
+		struct umc_driver *umc_drv = to_umc_driver(dev->driver);
+
+		if (umc_drv->pre_reset)
+			ret = umc_drv->pre_reset(umc);
+		else
+			device_release_driver(dev);
+	}
+	return ret;
+}
+
+static int umc_bus_post_reset_helper(struct device *dev, void *data)
+{
+	int ret = 0;
+
+	if (dev->driver) {
+		struct umc_dev *umc = to_umc_dev(dev);
+		struct umc_driver *umc_drv = to_umc_driver(dev->driver);
+
+		if (umc_drv->post_reset)
+			ret = umc_drv->post_reset(umc);
+	} else
+		ret = device_attach(dev);
+
+	return ret;
+}
+
+/**
+ * umc_controller_reset - reset the whole UMC controller
+ * @umc: the UMC device for the radio controller.
+ *
+ * Drivers or all capabilities of the controller will have their
+ * pre_reset methods called or be unbound from their device.  Then all
+ * post_reset methods will be called or the drivers will be rebound.
+ *
+ * Radio controllers must provide pre_reset and post_reset methods and
+ * reset the hardware in their start method.
+ *
+ * If this is called while a probe() or remove() is in progress it
+ * will return -EAGAIN and not perform the reset.
+ */
+int umc_controller_reset(struct umc_dev *umc)
+{
+	struct device *parent = umc->dev.parent;
+	int ret = 0;
+
+	if (!device_trylock(parent))
+		return -EAGAIN;
+	ret = device_for_each_child(parent, parent, umc_bus_pre_reset_helper);
+	if (ret >= 0)
+		ret = device_for_each_child(parent, parent, umc_bus_post_reset_helper);
+	device_unlock(parent);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(umc_controller_reset);
+
+/**
+ * umc_match_pci_id - match a UMC driver to a UMC device's parent PCI device.
+ * @umc_drv: umc driver with match_data pointing to a zero-terminated
+ * table of pci_device_id's.
+ * @umc: umc device whose parent is to be matched.
+ */
+int umc_match_pci_id(struct umc_driver *umc_drv, struct umc_dev *umc)
+{
+	const struct pci_device_id *id_table = umc_drv->match_data;
+	struct pci_dev *pci;
+
+	if (!dev_is_pci(umc->dev.parent))
+		return 0;
+
+	pci = to_pci_dev(umc->dev.parent);
+	return pci_match_id(id_table, pci) != NULL;
+}
+EXPORT_SYMBOL_GPL(umc_match_pci_id);
+
+static int umc_bus_rescan_helper(struct device *dev, void *data)
+{
+	int ret = 0;
+
+	if (!dev->driver)
+		ret = device_attach(dev);
+
+	return ret;
+}
+
+static void umc_bus_rescan(struct device *parent)
+{
+	int err;
+
+	/*
+	 * We can't use bus_rescan_devices() here as it deadlocks when
+	 * it tries to retake the dev->parent semaphore.
+	 */
+	err = device_for_each_child(parent, NULL, umc_bus_rescan_helper);
+	if (err < 0)
+		printk(KERN_WARNING "%s: rescan of bus failed: %d\n",
+		       KBUILD_MODNAME, err);
+}
+
+static int umc_bus_match(struct device *dev, struct device_driver *drv)
+{
+	struct umc_dev *umc = to_umc_dev(dev);
+	struct umc_driver *umc_driver = to_umc_driver(drv);
+
+	if (umc->cap_id == umc_driver->cap_id) {
+		if (umc_driver->match)
+			return umc_driver->match(umc_driver, umc);
+		else
+			return 1;
+	}
+	return 0;
+}
+
+static int umc_device_probe(struct device *dev)
+{
+	struct umc_dev *umc;
+	struct umc_driver *umc_driver;
+	int err;
+
+	umc_driver = to_umc_driver(dev->driver);
+	umc = to_umc_dev(dev);
+
+	get_device(dev);
+	err = umc_driver->probe(umc);
+	if (err)
+		put_device(dev);
+	else
+		umc_bus_rescan(dev->parent);
+
+	return err;
+}
+
+static int umc_device_remove(struct device *dev)
+{
+	struct umc_dev *umc;
+	struct umc_driver *umc_driver;
+
+	umc_driver = to_umc_driver(dev->driver);
+	umc = to_umc_dev(dev);
+
+	umc_driver->remove(umc);
+	put_device(dev);
+	return 0;
+}
+
+static ssize_t capability_id_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct umc_dev *umc = to_umc_dev(dev);
+
+	return sprintf(buf, "0x%02x\n", umc->cap_id);
+}
+static DEVICE_ATTR_RO(capability_id);
+
+static ssize_t version_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct umc_dev *umc = to_umc_dev(dev);
+
+	return sprintf(buf, "0x%04x\n", umc->version);
+}
+static DEVICE_ATTR_RO(version);
+
+static struct attribute *umc_dev_attrs[] = {
+	&dev_attr_capability_id.attr,
+	&dev_attr_version.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(umc_dev);
+
+struct bus_type umc_bus_type = {
+	.name		= "umc",
+	.match		= umc_bus_match,
+	.probe		= umc_device_probe,
+	.remove		= umc_device_remove,
+	.dev_groups	= umc_dev_groups,
+};
+EXPORT_SYMBOL_GPL(umc_bus_type);
+
+static int __init umc_bus_init(void)
+{
+	return bus_register(&umc_bus_type);
+}
+module_init(umc_bus_init);
+
+static void __exit umc_bus_exit(void)
+{
+	bus_unregister(&umc_bus_type);
+}
+module_exit(umc_bus_exit);
+
+MODULE_DESCRIPTION("UWB Multi-interface Controller capability bus");
+MODULE_AUTHOR("Cambridge Silicon Radio Ltd.");
+MODULE_LICENSE("GPL");