[Intel-wired-lan] virtual-bus[v2]: Implementation of Virtual Bus
Ertman, David M
david.m.ertman at intel.com
Fri Nov 15 21:17:20 UTC 2019
virtual-bus: Implementation of Virtual Bus
From: Dave Ertman <david.m.ertman at intel.com>
This is the initial implementation of the Virtual Bus,
virtbus_device and virtbus_driver. The virtual bus is
a software based bus intended to support lightweight
devices and drivers and provide matching between them
and probing of the registered drivers.
Files added:
drivers/bus/virtual_bus.c
include/linux/virtual_bus.h
Documentation/driver-api/virtual_bus.rst
The primary purpose of the virual bus is to provide
matching services and to pass the data pointer
contained in the virtbus_device to the virtbus_driver
during its probe call. This will allow two separate
kernel objects to match up and start communication.
The bus will support probe/remove shutdown and
suspend/resume callbacks.
Kconfig and Makefile alterations are included
Signed-off-by: Dave Ertman <david.m.ertman at intel.com>
Signed-off-by: Kiran Patil <kiran.patil at intel.com>
---
Documentation/driver-api/virtual_bus.rst | 76 +++++
drivers/bus/Kconfig | 14 +
drivers/bus/Makefile | 1
drivers/bus/virtual_bus.c | 326 ++++++++++++++++++++
include/linux/virtual_bus.h | 55 +++
.../selftests/virtual_bus/virtual_bus_dev/Makefile | 7
.../virtual_bus/virtual_bus_dev/virtual_bus_dev.c | 67 ++++
.../selftests/virtual_bus/virtual_bus_drv/Makefile | 7
.../virtual_bus/virtual_bus_drv/virtual_bus_drv.c | 101 ++++++
9 files changed, 654 insertions(+)
create mode 100644 Documentation/driver-api/virtual_bus.rst
create mode 100644 drivers/bus/virtual_bus.c
create mode 100644 include/linux/virtual_bus.h
create mode 100644 tools/testing/selftests/virtual_bus/virtual_bus_dev/Makefile
create mode 100644 tools/testing/selftests/virtual_bus/virtual_bus_dev/virtual_bus_dev.c
create mode 100644 tools/testing/selftests/virtual_bus/virtual_bus_drv/Makefile
create mode 100644 tools/testing/selftests/virtual_bus/virtual_bus_drv/virtual_bus_drv.c
diff --git a/Documentation/driver-api/virtual_bus.rst b/Documentation/driver-api/virtual_bus.rst
new file mode 100644
index 000000000000..970e06267284
--- /dev/null
+++ b/Documentation/driver-api/virtual_bus.rst
@@ -0,0 +1,76 @@
+===============================
+Virtual Bus Devices and Drivers
+===============================
+
+See <linux/virtual_bus.h> for the models for virtbus_device and virtbus_driver.
+This bus is meant to be a lightweight software based bus to attach generic
+devices and drivers to so that a chunk of data can be passed between them.
+
+One use case example is an rdma driver needing to connect with several
+different types of PCI LAN devices to be able to request resources from
+them (queue sets). Each LAN driver that supports rdma will register a
+virtbus_device on the virtual bus for each physical function. The rdma
+driver will register as a virtbus_driver on the virtual bus to be
+matched up with multiple virtbus_devices and receive a pointer to a
+struct containing the callbacks that the PCI LAN drivers support for
+registering with them.
+
+Sections in this document:
+ Virtbus devices
+ Virtbus drivers
+ Device Enumeration
+ Device naming and driver binding
+ Virtual Bus API entry points
+
+Virtbus devices
+~~~~~~~~~~~~~~~
+Virtbus_devices are lightweight objects that support the minimal device
+functionality. Devices will accept a name, and then an automatically
+generated index is concatenated onto it for the virtbus_device->name.
+
+The memory backing the "void *data" element of the virtbus_device is
+expected to be allocated and freed outside the context of the bus
+operations. This memory is also expected to remain viable for the
+duration of the time that the virtbus_device is registered to the
+virtual bus. (e.g. from before the virtbus_dev_register until after
+the paired virtbus_dev_unregister).
+
+The provided API for virtbus_dev_alloc is an efficient way of allocating
+the memory for the virtbus_device (except for the data element) and
+automatically freeing it when the device is removed from the bus.
+
+Virtbus drivers
+~~~~~~~~~~~~~~~
+Virtbus drivers register with the virtual bus to be matched with virtbus
+devices. They expect to be registered with a probe and remove callback,
+and also support shutdown, suspend, and resume callbacks. They otherwise
+follow the standard driver behavior of having discovery and enumeration
+handled in the bus infrastructure.
+
+Virtbus drivers register themselves with the API entry point virtbus_drv_reg
+and unregister with virtbus_drv_unreg.
+
+Device Enumeration
+~~~~~~~~~~~~~~~~~~
+Enumeration is handled automatically by the bus infrastructure via the
+ida_simple methods.
+
+Device naming and driver binding
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+The virtbus_device.dev.name is the canonical name for the device. It is
+built from two other parts:
+
+ - virtbus_device.name (also used for matching).
+ - virtbus_device.id (generated automatically from ida_simple calls)
+
+This allows for multiple virtbus_devices with the same name, which will all
+be matched to the same virtbus_driver. Driver binding is performed by the
+driver core, invoking driver probe() after finding a match between device and driver.
+
+Virtual Bus API entry points
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+struct virtbus_device *virtbus_dev_alloc(const char *name, void *data)
+int virtbus_dev_register(struct virtbus_device *vdev)
+void virtbus_dev_unregister(struct virtbus_device *vdev)
+int virtbus_drv_register(struct virtbus_driver *vdrv, struct module *owner)
+void virtbus_drv_unregister(struct virtbus_driver *vdrv)
diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 6b331061d34b..30cef35b0c30 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -193,4 +193,18 @@ config DA8XX_MSTPRI
source "drivers/bus/fsl-mc/Kconfig"
+config VIRTUAL_BUS
+ tristate "lightweight Virtual Bus"
+ depends on PM
+ help
+ Provides a lightweight bus for virtbus_devices to be added to it
+ and virtbus_drivers to be registered on it. Will create a match
+ between the driver and device, then call the driver's probe with
+ the virtbus_device's struct (including a pointer for data).
+ One example is the irdma driver needing to connect with various
+ PCI LAN drivers to request resources (queues) to be able to perform
+ its function. The data in the virtbus_device created by the
+ PCI LAN driver is a set of ops (function pointers) for the irdma
+ driver to use to register and communicate with the PCI LAN driver.
+
endmenu
diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile
index 16b43d3468c6..0b0ba53cbe5b 100644
--- a/drivers/bus/Makefile
+++ b/drivers/bus/Makefile
@@ -33,3 +33,4 @@ obj-$(CONFIG_UNIPHIER_SYSTEM_BUS) += uniphier-system-bus.o
obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress-config.o
obj-$(CONFIG_DA8XX_MSTPRI) += da8xx-mstpri.o
+obj-$(CONFIG_VIRTUAL_BUS) += virtual_bus.o
diff --git a/drivers/bus/virtual_bus.c b/drivers/bus/virtual_bus.c
new file mode 100644
index 000000000000..bb069313f700
--- /dev/null
+++ b/drivers/bus/virtual_bus.c
@@ -0,0 +1,326 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * virtual_bus.c - lightweight software based bus for virtual devices
+ *
+ * Copyright (c) 2019-20 Intel Corporation
+ *
+ * Please see Documentation/driver-api/virtual_bus.rst for
+ * more information
+ */
+
+#include <linux/string.h>
+#include <linux/virtual_bus.h>
+#include <linux/of_irq.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/pm_runtime.h>
+#include <linux/pm_domain.h>
+#include <linux/acpi.h>
+#include <linux/device.h>
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Lightweight Virtual Bus");
+MODULE_AUTHOR("David Ertman <david.m.ertman at intel.com>");
+MODULE_AUTHOR("Kiran Patil <kiran.patil at intel.com>");
+
+static DEFINE_IDA(virtbus_dev_ida);
+
+static const
+struct virtbus_dev_id *virtbus_match_id(const struct virtbus_dev_id *id,
+ struct virtbus_device *vdev)
+{
+ while (id->name[0]) {
+ if (!strcmp(vdev->name, id->name)) {
+ vdev->dev_id = id;
+ return id;
+ }
+ id++;
+ }
+ return NULL;
+}
+
+#define to_virtbus_dev(dev) container_of((dev), struct virtbus_device, dev)
+#define to_virtbus_drv(drv) (container_of((drv), struct virtbus_driver, \
+ driver))
+
+/**
+ * virtbus_match - bind virtbus device to virtbus driver
+ * @dev: device
+ * @drv: driver
+ *
+ * Virtbus device IDs are always in "<name>.<instance>" format.
+ * Instances are automatically selected through an ida_simple_get so
+ * are positive integers. Names are taken from the device name field.
+ * Driver IDs are simple <name>. Need to extract the name from the
+ * Virtual Device compare to name of the driver.
+ */
+static int virtbus_match(struct device *dev, struct device_driver *drv)
+{
+ struct virtbus_driver *vdrv = to_virtbus_drv(drv);
+ struct virtbus_device *vdev = to_virtbus_dev(dev);
+
+ if (vdrv->id_table)
+ return virtbus_match_id(vdrv->id_table, vdev) != NULL;
+
+ return !strcmp(vdev->name, drv->name);
+}
+
+/**
+ * virtbus_probe - call probe of the virtbus_drv
+ * @dev: device struct
+ */
+static int virtbus_probe(struct device *dev)
+{
+ if (dev->driver->probe)
+ return dev->driver->probe(dev);
+
+ return 0;
+}
+
+static int virtbus_remove(struct device *dev)
+{
+ if (dev->driver->remove)
+ return dev->driver->remove(dev);
+
+ return 0;
+}
+
+static void virtbus_shutdown(struct device *dev)
+{
+ if (dev->driver->shutdown)
+ dev->driver->shutdown(dev);
+}
+
+static int virtbus_suspend(struct device *dev, pm_message_t state)
+{
+ if (dev->driver->suspend)
+ return dev->driver->suspend(dev, state);
+
+ return 0;
+}
+
+static int virtbus_resume(struct device *dev)
+{
+ if (dev->driver->resume)
+ return dev->driver->resume(dev);
+
+ return 0;
+}
+
+struct bus_type virtual_bus_type = {
+ .name = "virtbus",
+ .match = virtbus_match,
+ .probe = virtbus_probe,
+ .remove = virtbus_remove,
+ .shutdown = virtbus_shutdown,
+ .suspend = virtbus_suspend,
+ .resume = virtbus_resume,
+};
+
+/**
+ * virtbus_dev_register - add a virtual bus device
+ * @vdev: virtual bus device to add
+ */
+int virtbus_dev_register(struct virtbus_device *vdev)
+{
+ int ret;
+
+ if (!vdev)
+ return -EINVAL;
+
+ device_initialize(&vdev->dev);
+
+ vdev->dev.bus = &virtual_bus_type;
+ /* All device IDs are automatically allocated */
+ ret = ida_simple_get(&virtbus_dev_ida, 0, 0, GFP_KERNEL);
+ if (ret < 0)
+ return ret;
+
+ vdev->id = ret;
+ dev_set_name(&vdev->dev, "%s.%d", vdev->name, vdev->id);
+
+ dev_dbg(&vdev->dev, "Registering VirtBus device '%s'\n",
+ dev_name(&vdev->dev));
+
+ ret = device_add(&vdev->dev);
+ if (!ret)
+ return ret;
+
+ /* Error adding virtual device */
+ device_del(&vdev->dev);
+ ida_simple_remove(&virtbus_dev_ida, vdev->id);
+ vdev->id = VIRTBUS_DEVID_NONE;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(virtbus_dev_register);
+
+/**
+ * virtbus_dev_unregister - remove a virtual bus device
+ * vdev: virtual bus device we are removing
+ */
+void virtbus_dev_unregister(struct virtbus_device *vdev)
+{
+ if (!IS_ERR_OR_NULL(vdev)) {
+ device_del(&vdev->dev);
+
+ ida_simple_remove(&virtbus_dev_ida, vdev->id);
+ vdev->id = VIRTBUS_DEVID_NONE;
+ }
+}
+EXPORT_SYMBOL_GPL(virtbus_dev_unregister);
+
+struct virtbus_object {
+ struct virtbus_device vdev;
+ char name[];
+};
+
+/**
+ * virtbus_dev_release - Destroy a virtbus device
+ * @vdev: virtual device to release
+ *
+ * Note that the vdev->data which is separately allocated needs to be
+ * separately freed on it own.
+ */
+static void virtbus_dev_release(struct device *dev)
+{
+ struct virtbus_object *vo = container_of(dev, struct virtbus_object,
+ vdev.dev);
+
+ kfree(vo);
+}
+
+/**
+ * virtbus_dev_alloc - allocate a virtbus device
+ * @name: name to associate with the vdev
+ * @data: pointer to data to be associated with this device
+ */
+struct virtbus_device *virtbus_dev_alloc(const char *name, void *data)
+{
+ struct virtbus_object *vo;
+
+ /* Create a virtbus object to contain the vdev and name. This
+ * avoids a problem with the const attribute of name in the vdev.
+ * The virtbus_object will be allocated here and freed in the
+ * release function.
+ */
+ vo = kzalloc(sizeof(*vo) + strlen(name) + 1, GFP_KERNEL);
+ if (!vo)
+ return NULL;
+
+ strcpy(vo->name, name);
+ vo->vdev.name = vo->name;
+ vo->vdev.data = data;
+ vo->vdev.dev.release = virtbus_dev_release;
+
+ return &vo->vdev;
+}
+EXPORT_SYMBOL_GPL(virtbus_dev_alloc);
+
+static int virtbus_drv_probe(struct device *_dev)
+{
+ struct virtbus_driver *vdrv = to_virtbus_drv(_dev->driver);
+ struct virtbus_device *vdev = to_virtbus_dev(_dev);
+ int ret;
+
+ ret = dev_pm_domain_attach(_dev, true);
+ if (ret) {
+ dev_warn(_dev, "Failed to attatch to PM Domain : %d\n", ret);
+ return ret;
+ }
+
+ if (vdrv->probe) {
+ ret = vdrv->probe(vdev);
+ if (ret)
+ dev_pm_domain_detach(_dev, true);
+ }
+
+ return ret;
+}
+
+static int virtbus_drv_remove(struct device *_dev)
+{
+ struct virtbus_driver *vdrv = to_virtbus_drv(_dev->driver);
+ struct virtbus_device *vdev = to_virtbus_dev(_dev);
+ int ret = 0;
+
+ if (vdrv->remove)
+ ret = vdrv->remove(vdev);
+
+ dev_pm_domain_detach(_dev, true);
+
+ return ret;
+}
+
+static void virtbus_drv_shutdown(struct device *_dev)
+{
+ struct virtbus_driver *vdrv = to_virtbus_drv(_dev->driver);
+ struct virtbus_device *vdev = to_virtbus_dev(_dev);
+
+ if (vdrv->shutdown)
+ vdrv->shutdown(vdev);
+}
+
+static int virtbus_drv_suspend(struct device *_dev, pm_message_t state)
+{
+ struct virtbus_driver *vdrv = to_virtbus_drv(_dev->driver);
+ struct virtbus_device *vdev = to_virtbus_dev(_dev);
+
+ if (vdrv->suspend)
+ return vdrv->suspend(vdev, state);
+
+ return 0;
+}
+
+static int virtbus_drv_resume(struct device *_dev)
+{
+ struct virtbus_driver *vdrv = to_virtbus_drv(_dev->driver);
+ struct virtbus_device *vdev = to_virtbus_dev(_dev);
+
+ if (vdrv->resume)
+ return vdrv->resume(vdev);
+
+ return 0;
+}
+
+/**
+ * __virtbus_drv_register - register a driver for virtual bus devices
+ * @vdrv: virtbus_driver structure
+ * @owner: owning module/driver
+ */
+int __virtbus_drv_register(struct virtbus_driver *vdrv, struct module *owner)
+{
+ vdrv->driver.owner = owner;
+ vdrv->driver.bus = &virtual_bus_type;
+ vdrv->driver.probe = virtbus_drv_probe;
+ vdrv->driver.remove = virtbus_drv_remove;
+ vdrv->driver.shutdown = virtbus_drv_shutdown;
+ vdrv->driver.suspend = virtbus_drv_suspend;
+ vdrv->driver.resume = virtbus_drv_resume;
+
+ return driver_register(&vdrv->driver);
+}
+EXPORT_SYMBOL_GPL(__virtbus_drv_register);
+
+/**
+ * virtbus_drv_unregister - unregister a driver for virtual bus devices
+ * @drv: virtbus_driver structure
+ */
+void virtbus_drv_unregister(struct virtbus_driver *vdrv)
+{
+ driver_unregister(&vdrv->driver);
+}
+EXPORT_SYMBOL_GPL(virtbus_drv_unregister);
+
+static int __init virtual_bus_init(void)
+{
+ return bus_register(&virtual_bus_type);
+}
+
+static void __exit virtual_bus_exit(void)
+{
+ bus_unregister(&virtual_bus_type);
+}
+
+module_init(virtual_bus_init);
+module_exit(virtual_bus_exit);
diff --git a/include/linux/virtual_bus.h b/include/linux/virtual_bus.h
new file mode 100644
index 000000000000..b6f2406180f8
--- /dev/null
+++ b/include/linux/virtual_bus.h
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * virtual_bus.h - lightweight software bus
+ *
+ * Copyright (c) 2019-20 Intel Corporation
+ *
+ * Please see Documentation/driver-api/virtual_bus.rst for more information
+ */
+
+#ifndef _VIRTUAL_BUS_H_
+#define _VIRTUAL_BUS_H_
+
+#include <linux/device.h>
+
+#define VIRTBUS_DEVID_NONE (-1)
+#define VIRTBUS_NAME_SIZE 20
+
+struct virtbus_dev_id {
+ char name[VIRTBUS_NAME_SIZE];
+ u64 driver_data;
+};
+
+struct virtbus_device {
+ const char *name;
+ int id;
+ const struct virtbus_dev_id *dev_id;
+ struct device dev;
+ void *data;
+};
+
+/* If the driver uses a id_table to match with virtbus_devices, then the
+ * memory for the table is expected to remain allocated for the duration
+ * of the pairing between driver and device. The pointer for the matching
+ * element will be copied to the dev_id field of the virtbus_device.
+ */
+struct virtbus_driver {
+ int (*probe)(struct virtbus_device *);
+ int (*remove)(struct virtbus_device *);
+ void (*shutdown)(struct virtbus_device *);
+ int (*suspend)(struct virtbus_device *, pm_message_t);
+ int (*resume)(struct virtbus_device *);
+ struct device_driver driver;
+ const struct virtbus_dev_id *id_table;
+};
+
+int virtbus_dev_register(struct virtbus_device *vdev);
+void virtbus_dev_unregister(struct virtbus_device *vdev);
+struct virtbus_device *virtbus_dev_alloc(const char *name, void *devdata);
+int __virtbus_drv_register(struct virtbus_driver *vdrv, struct module *owner);
+void virtbus_drv_unregister(struct virtbus_driver *vdrv);
+
+#define virtbus_drv_register(vdrv) \
+ __virtbus_drv_register(vdrv, THIS_MODULE)
+
+#endif /* _VIRTUAL_BUS_H_ */
diff --git a/tools/testing/selftests/virtual_bus/virtual_bus_dev/Makefile b/tools/testing/selftests/virtual_bus/virtual_bus_dev/Makefile
new file mode 100644
index 000000000000..ddd5088eb26b
--- /dev/null
+++ b/tools/testing/selftests/virtual_bus/virtual_bus_dev/Makefile
@@ -0,0 +1,7 @@
+obj-m += virtual_bus_dev.o
+
+all:
+ make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
+
+clean:
+ make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
diff --git a/tools/testing/selftests/virtual_bus/virtual_bus_dev/virtual_bus_dev.c b/tools/testing/selftests/virtual_bus/virtual_bus_dev/virtual_bus_dev.c
new file mode 100644
index 000000000000..29b456d0a158
--- /dev/null
+++ b/tools/testing/selftests/virtual_bus/virtual_bus_dev/virtual_bus_dev.c
@@ -0,0 +1,67 @@
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/module.h>
+#include <linux/virtual_bus.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Dave Ertman");
+MODULE_DESCRIPTION("Test to create a device on virtual bus");
+MODULE_VERSION("1.0");
+
+static struct virtbus_device *vdev;
+static char *data;
+
+static int __init test_dev_init(void)
+{
+ int ret = 0;
+ static char *name;
+
+ printk(KERN_INFO "Loading Virtual Bus Test Device\n");
+
+ name = kzalloc(VIRTBUS_NAME_SIZE, GFP_KERNEL);
+ if (!name)
+ return -ENOMEM;
+ strcpy(name, "virtual_bus_dev");
+
+ data = kzalloc(128, GFP_KERNEL);
+ if (!data) {
+ kfree(name);
+ return -ENOMEM;
+ }
+ strcpy(data, "This is my data string - isn't it wonderful!");
+
+ vdev = virtbus_dev_alloc(name, data);
+ if (!vdev) {
+ kfree(name);
+ kfree(data);
+ return -EINVAL;
+ }
+
+ printk(KERN_ERR "Virtbus Device allocated:\n\t%s\n\t%s\n", vdev->name,
+ (char *)vdev->data);
+
+ ret = virtbus_dev_register(vdev);
+ kfree(name);
+ if(ret) {
+ printk(KERN_ERR "FAILED TO ADD VIRTBUS DEVICE %d\n", ret);
+ return ret;
+ }
+
+ printk(KERN_INFO "Virtual Device created\n");
+ return ret;
+}
+
+static void __exit test_dev_exit(void)
+{
+ printk(KERN_INFO "Exiting Virtual Bus Test Device");
+
+ virtbus_dev_unregister(vdev);
+ kfree(data);
+
+ printk(KERN_INFO "Virtual Bus Test Device removed\n");
+}
+
+module_init(test_dev_init);
+module_exit(test_dev_exit);
diff --git a/tools/testing/selftests/virtual_bus/virtual_bus_drv/Makefile b/tools/testing/selftests/virtual_bus/virtual_bus_drv/Makefile
new file mode 100644
index 000000000000..a4b7467f7878
--- /dev/null
+++ b/tools/testing/selftests/virtual_bus/virtual_bus_drv/Makefile
@@ -0,0 +1,7 @@
+obj-m += virtual_bus_drv.o
+
+all:
+ make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
+
+clean:
+ make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
diff --git a/tools/testing/selftests/virtual_bus/virtual_bus_drv/virtual_bus_drv.c b/tools/testing/selftests/virtual_bus/virtual_bus_drv/virtual_bus_drv.c
new file mode 100644
index 000000000000..202288809b1c
--- /dev/null
+++ b/tools/testing/selftests/virtual_bus/virtual_bus_drv/virtual_bus_drv.c
@@ -0,0 +1,101 @@
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/module.h>
+#include <linux/virtual_bus.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Dave Ertman");
+MODULE_DESCRIPTION("Test to register a driver on virtual bus");
+MODULE_VERSION("1.0");
+
+static int td_probe(struct virtbus_device *vdev)
+{
+ printk(KERN_ERR "VIRTBUS DRIVER PROBED\n");
+ printk(KERN_ERR "DATA IS %s", vdev->data ? "NOT NULL" : "NULL");
+ if (vdev->dev_id) {
+ printk(KERN_ERR "DEV_ID->DATA 0x%08x\n",
+ (uint)vdev->dev_id->driver_data);
+ if (vdev->dev_id->driver_data == 1)
+ printk(KERN_ERR "DATA STRING: %s\n",
+ (char *)vdev->data);
+ } else {
+ printk(KERN_ERR "DEV_ID->DATA is NULL\n");
+ }
+
+ return 0;
+}
+
+static int td_remove(struct virtbus_device *vdev)
+{
+ printk(KERN_ERR "VIRTBUS DRIVER REMOVED\n");
+ return 0;
+}
+
+static void td_shutdown(struct virtbus_device *vdev)
+{
+ printk(KERN_ERR "VIRTBUS DRIVER SHUTDOWN\n");
+}
+
+static const struct virtbus_dev_id vdev_id_table[] = {
+
+ {
+ .name = "NOT THE NAME",
+ .driver_data = 0x00000000,
+ },
+ {
+ .name = "virtual_bus_dev",
+ .driver_data = 0x00000001,
+ },
+ {
+ .name = "ice_rdma",
+ .driver_data = 0x00000002,
+ },
+ {
+ .name = "YET AGAIN NOT NAME",
+ .driver_data = 0x00000003,
+ },
+};
+
+static struct virtbus_driver vdrv = {
+ .probe = td_probe,
+ .remove = td_remove,
+ .shutdown = td_shutdown,
+ .driver = {
+ .name = "virtual_bus_dev",
+ },
+};
+
+static int __init test_drv_init(void)
+{
+ int ret;
+
+ printk(KERN_INFO "Registering Virtual Bus Test Driver\n");
+
+ /* To do a simple match, leave the id_table as NULL */
+ vdrv.id_table = &vdev_id_table[0];
+
+ printk(KERN_ERR "name of 0 is %s\n", vdrv.id_table->name);
+
+ ret = virtbus_drv_register(&vdrv);
+
+ if (!ret)
+ printk(KERN_INFO "Virtual Driver registered\n");
+ else
+ printk(KERN_INFO "Virtual Driver FAILED!!\n");
+
+ return ret;
+}
+
+static void __exit test_drv_exit(void)
+{
+ printk(KERN_INFO "Exiting Virtual Bus Test Driver");
+
+ virtbus_drv_unregister(&vdrv);
+
+ printk(KERN_INFO "Virtual Bus Test Driver removed\n");
+}
+
+module_init(test_drv_init);
+module_exit(test_drv_exit);
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