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authorMatt Porter <mporter@kernel.crashing.org>2005-11-07 01:00:15 -0800
committerLinus Torvalds <torvalds@g5.osdl.org>2005-11-07 07:53:46 -0800
commit394b701ce4fbfde919a9bcbf84cb4820a7c6d47c (patch)
treea397fff4043a9810e753fb81224349bd36db45b8 /drivers/rapidio/rio-driver.c
parentd217d5450f11d8c907c0458d175b0dc999b4d06d (diff)
downloadlinux-394b701ce4fbfde919a9bcbf84cb4820a7c6d47c.tar.bz2
[PATCH] RapidIO support: core base
Adds a RapidIO subsystem to the kernel. RIO is a switched fabric interconnect used in higher-end embedded applications. The curious can look at the specs over at http://www.rapidio.org The core code implements enumeration/discovery, management of devices/resources, and interfaces for RIO drivers. There's a lot more to do to take advantages of all the hardware features. However, this should provide a good base for folks with RIO hardware to start contributing. Signed-off-by: Matt Porter <mporter@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/rapidio/rio-driver.c')
-rw-r--r--drivers/rapidio/rio-driver.c229
1 files changed, 229 insertions, 0 deletions
diff --git a/drivers/rapidio/rio-driver.c b/drivers/rapidio/rio-driver.c
new file mode 100644
index 000000000000..dc749609699a
--- /dev/null
+++ b/drivers/rapidio/rio-driver.c
@@ -0,0 +1,229 @@
+/*
+ * RapidIO driver support
+ *
+ * Copyright 2005 MontaVista Software, Inc.
+ * Matt Porter <mporter@kernel.crashing.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/rio.h>
+#include <linux/rio_ids.h>
+
+#include "rio.h"
+
+/**
+ * rio_match_device - Tell if a RIO device has a matching RIO device id structure
+ * @id: the RIO device id structure to match against
+ * @rdev: the RIO device structure to match against
+ *
+ * Used from driver probe and bus matching to check whether a RIO device
+ * matches a device id structure provided by a RIO driver. Returns the
+ * matching &struct rio_device_id or %NULL if there is no match.
+ */
+static const struct rio_device_id *rio_match_device(const struct rio_device_id
+ *id,
+ const struct rio_dev *rdev)
+{
+ while (id->vid || id->asm_vid) {
+ if (((id->vid == RIO_ANY_ID) || (id->vid == rdev->vid)) &&
+ ((id->did == RIO_ANY_ID) || (id->did == rdev->did)) &&
+ ((id->asm_vid == RIO_ANY_ID)
+ || (id->asm_vid == rdev->asm_vid))
+ && ((id->asm_did == RIO_ANY_ID)
+ || (id->asm_did == rdev->asm_did)))
+ return id;
+ id++;
+ }
+ return NULL;
+}
+
+/**
+ * rio_dev_get - Increments the reference count of the RIO device structure
+ *
+ * @rdev: RIO device being referenced
+ *
+ * Each live reference to a device should be refcounted.
+ *
+ * Drivers for RIO devices should normally record such references in
+ * their probe() methods, when they bind to a device, and release
+ * them by calling rio_dev_put(), in their disconnect() methods.
+ */
+struct rio_dev *rio_dev_get(struct rio_dev *rdev)
+{
+ if (rdev)
+ get_device(&rdev->dev);
+
+ return rdev;
+}
+
+/**
+ * rio_dev_put - Release a use of the RIO device structure
+ *
+ * @rdev: RIO device being disconnected
+ *
+ * Must be called when a user of a device is finished with it.
+ * When the last user of the device calls this function, the
+ * memory of the device is freed.
+ */
+void rio_dev_put(struct rio_dev *rdev)
+{
+ if (rdev)
+ put_device(&rdev->dev);
+}
+
+/**
+ * rio_device_probe - Tell if a RIO device structure has a matching RIO
+ * device id structure
+ * @id: the RIO device id structure to match against
+ * @dev: the RIO device structure to match against
+ *
+ * return 0 and set rio_dev->driver when drv claims rio_dev, else error
+ */
+static int rio_device_probe(struct device *dev)
+{
+ struct rio_driver *rdrv = to_rio_driver(dev->driver);
+ struct rio_dev *rdev = to_rio_dev(dev);
+ int error = -ENODEV;
+ const struct rio_device_id *id;
+
+ if (!rdev->driver && rdrv->probe) {
+ if (!rdrv->id_table)
+ return error;
+ id = rio_match_device(rdrv->id_table, rdev);
+ rio_dev_get(rdev);
+ if (id)
+ error = rdrv->probe(rdev, id);
+ if (error >= 0) {
+ rdev->driver = rdrv;
+ error = 0;
+ rio_dev_put(rdev);
+ }
+ }
+ return error;
+}
+
+/**
+ * rio_device_remove - Remove a RIO device from the system
+ *
+ * @dev: the RIO device structure to match against
+ *
+ * Remove a RIO device from the system. If it has an associated
+ * driver, then run the driver remove() method. Then update
+ * the reference count.
+ */
+static int rio_device_remove(struct device *dev)
+{
+ struct rio_dev *rdev = to_rio_dev(dev);
+ struct rio_driver *rdrv = rdev->driver;
+
+ if (rdrv) {
+ if (rdrv->remove)
+ rdrv->remove(rdev);
+ rdev->driver = NULL;
+ }
+
+ rio_dev_put(rdev);
+
+ return 0;
+}
+
+/**
+ * rio_register_driver - register a new RIO driver
+ * @rdrv: the RIO driver structure to register
+ *
+ * Adds a &struct rio_driver to the list of registered drivers
+ * Returns a negative value on error, otherwise 0. If no error
+ * occurred, the driver remains registered even if no device
+ * was claimed during registration.
+ */
+int rio_register_driver(struct rio_driver *rdrv)
+{
+ /* initialize common driver fields */
+ rdrv->driver.name = rdrv->name;
+ rdrv->driver.bus = &rio_bus_type;
+ rdrv->driver.probe = rio_device_probe;
+ rdrv->driver.remove = rio_device_remove;
+
+ /* register with core */
+ return driver_register(&rdrv->driver);
+}
+
+/**
+ * rio_unregister_driver - unregister a RIO driver
+ * @rdrv: the RIO driver structure to unregister
+ *
+ * Deletes the &struct rio_driver from the list of registered RIO
+ * drivers, gives it a chance to clean up by calling its remove()
+ * function for each device it was responsible for, and marks those
+ * devices as driverless.
+ */
+void rio_unregister_driver(struct rio_driver *rdrv)
+{
+ driver_unregister(&rdrv->driver);
+}
+
+/**
+ * rio_match_bus - Tell if a RIO device structure has a matching RIO
+ * driver device id structure
+ * @dev: the standard device structure to match against
+ * @drv: the standard driver structure containing the ids to match against
+ *
+ * Used by a driver to check whether a RIO device present in the
+ * system is in its list of supported devices. Returns 1 if
+ * there is a matching &struct rio_device_id or 0 if there is
+ * no match.
+ */
+static int rio_match_bus(struct device *dev, struct device_driver *drv)
+{
+ struct rio_dev *rdev = to_rio_dev(dev);
+ struct rio_driver *rdrv = to_rio_driver(drv);
+ const struct rio_device_id *id = rdrv->id_table;
+ const struct rio_device_id *found_id;
+
+ if (!id)
+ goto out;
+
+ found_id = rio_match_device(id, rdev);
+
+ if (found_id)
+ return 1;
+
+ out:return 0;
+}
+
+static struct device rio_bus = {
+ .bus_id = "rapidio",
+};
+
+struct bus_type rio_bus_type = {
+ .name = "rapidio",
+ .match = rio_match_bus,
+ .dev_attrs = rio_dev_attrs
+};
+
+/**
+ * rio_bus_init - Register the RapidIO bus with the device model
+ *
+ * Registers the RIO bus device and RIO bus type with the Linux
+ * device model.
+ */
+static int __init rio_bus_init(void)
+{
+ if (device_register(&rio_bus) < 0)
+ printk("RIO: failed to register RIO bus device\n");
+ return bus_register(&rio_bus_type);
+}
+
+postcore_initcall(rio_bus_init);
+
+EXPORT_SYMBOL_GPL(rio_register_driver);
+EXPORT_SYMBOL_GPL(rio_unregister_driver);
+EXPORT_SYMBOL_GPL(rio_bus_type);
+EXPORT_SYMBOL_GPL(rio_dev_get);
+EXPORT_SYMBOL_GPL(rio_dev_put);