Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / staging / i2o / driver.c
diff --git a/kernel/drivers/staging/i2o/driver.c b/kernel/drivers/staging/i2o/driver.c
new file mode 100644 (file)
index 0000000..06119bb
--- /dev/null
@@ -0,0 +1,381 @@
+/*
+ *     Functions to handle I2O drivers (OSMs) and I2O bus type for sysfs
+ *
+ *     Copyright (C) 2004      Markus Lidel <Markus.Lidel@shadowconnect.com>
+ *
+ *     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.
+ *
+ *     Fixes/additions:
+ *             Markus Lidel <Markus.Lidel@shadowconnect.com>
+ *                     initial version.
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/rwsem.h>
+#include "i2o.h"
+#include <linux/workqueue.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include "core.h"
+
+#define OSM_NAME       "i2o"
+
+/* max_drivers - Maximum I2O drivers (OSMs) which could be registered */
+static unsigned int i2o_max_drivers = I2O_MAX_DRIVERS;
+module_param_named(max_drivers, i2o_max_drivers, uint, 0);
+MODULE_PARM_DESC(max_drivers, "maximum number of OSM's to support");
+
+/* I2O drivers lock and array */
+static spinlock_t i2o_drivers_lock;
+static struct i2o_driver **i2o_drivers;
+
+/**
+ *     i2o_bus_match - Tell if I2O device class id matches the class ids of the I2O driver (OSM)
+ *     @dev: device which should be verified
+ *     @drv: the driver to match against
+ *
+ *     Used by the bus to check if the driver wants to handle the device.
+ *
+ *     Returns 1 if the class ids of the driver match the class id of the
+ *     device, otherwise 0.
+ */
+static int i2o_bus_match(struct device *dev, struct device_driver *drv)
+{
+       struct i2o_device *i2o_dev = to_i2o_device(dev);
+       struct i2o_driver *i2o_drv = to_i2o_driver(drv);
+       struct i2o_class_id *ids = i2o_drv->classes;
+
+       if (ids)
+               while (ids->class_id != I2O_CLASS_END) {
+                       if (ids->class_id == i2o_dev->lct_data.class_id)
+                               return 1;
+                       ids++;
+               }
+       return 0;
+};
+
+/* I2O bus type */
+struct bus_type i2o_bus_type = {
+       .name = "i2o",
+       .match = i2o_bus_match,
+       .dev_groups = i2o_device_groups,
+};
+
+/**
+ *     i2o_driver_register - Register a I2O driver (OSM) in the I2O core
+ *     @drv: I2O driver which should be registered
+ *
+ *     Registers the OSM drv in the I2O core and creates an event queues if
+ *     necessary.
+ *
+ *     Returns 0 on success or negative error code on failure.
+ */
+int i2o_driver_register(struct i2o_driver *drv)
+{
+       struct i2o_controller *c;
+       int i;
+       int rc = 0;
+       unsigned long flags;
+
+       osm_debug("Register driver %s\n", drv->name);
+
+       if (drv->event) {
+               drv->event_queue = alloc_workqueue("%s", WQ_MEM_RECLAIM, 1,
+                                                  drv->name);
+               if (!drv->event_queue) {
+                       osm_err("Could not initialize event queue for driver "
+                               "%s\n", drv->name);
+                       return -EFAULT;
+               }
+               osm_debug("Event queue initialized for driver %s\n", drv->name);
+       } else
+               drv->event_queue = NULL;
+
+       drv->driver.name = drv->name;
+       drv->driver.bus = &i2o_bus_type;
+
+       spin_lock_irqsave(&i2o_drivers_lock, flags);
+
+       for (i = 0; i2o_drivers[i]; i++)
+               if (i >= i2o_max_drivers) {
+                       osm_err("too many drivers registered, increase max_drivers\n");
+                       spin_unlock_irqrestore(&i2o_drivers_lock, flags);
+                       rc = -EFAULT;
+                       goto out;
+               }
+
+       drv->context = i;
+       i2o_drivers[i] = drv;
+
+       spin_unlock_irqrestore(&i2o_drivers_lock, flags);
+
+       osm_debug("driver %s gets context id %d\n", drv->name, drv->context);
+
+       list_for_each_entry(c, &i2o_controllers, list) {
+               struct i2o_device *i2o_dev;
+
+               i2o_driver_notify_controller_add(drv, c);
+               list_for_each_entry(i2o_dev, &c->devices, list)
+                   i2o_driver_notify_device_add(drv, i2o_dev);
+       }
+
+       rc = driver_register(&drv->driver);
+       if (rc)
+               goto out;
+
+       return 0;
+out:
+       if (drv->event_queue) {
+               destroy_workqueue(drv->event_queue);
+               drv->event_queue = NULL;
+       }
+
+       return rc;
+};
+
+/**
+ *     i2o_driver_unregister - Unregister a I2O driver (OSM) from the I2O core
+ *     @drv: I2O driver which should be unregistered
+ *
+ *     Unregisters the OSM drv from the I2O core and cleanup event queues if
+ *     necessary.
+ */
+void i2o_driver_unregister(struct i2o_driver *drv)
+{
+       struct i2o_controller *c;
+       unsigned long flags;
+
+       osm_debug("unregister driver %s\n", drv->name);
+
+       driver_unregister(&drv->driver);
+
+       list_for_each_entry(c, &i2o_controllers, list) {
+               struct i2o_device *i2o_dev;
+
+               list_for_each_entry(i2o_dev, &c->devices, list)
+                   i2o_driver_notify_device_remove(drv, i2o_dev);
+
+               i2o_driver_notify_controller_remove(drv, c);
+       }
+
+       spin_lock_irqsave(&i2o_drivers_lock, flags);
+       i2o_drivers[drv->context] = NULL;
+       spin_unlock_irqrestore(&i2o_drivers_lock, flags);
+
+       if (drv->event_queue) {
+               destroy_workqueue(drv->event_queue);
+               drv->event_queue = NULL;
+               osm_debug("event queue removed for %s\n", drv->name);
+       }
+};
+
+/**
+ *     i2o_driver_dispatch - dispatch an I2O reply message
+ *     @c: I2O controller of the message
+ *     @m: I2O message number
+ *
+ *     The reply is delivered to the driver from which the original message
+ *     was. This function is only called from interrupt context.
+ *
+ *     Returns 0 on success and the message should not be flushed. Returns > 0
+ *     on success and if the message should be flushed afterwords. Returns
+ *     negative error code on failure (the message will be flushed too).
+ */
+int i2o_driver_dispatch(struct i2o_controller *c, u32 m)
+{
+       struct i2o_driver *drv;
+       struct i2o_message *msg = i2o_msg_out_to_virt(c, m);
+       u32 context = le32_to_cpu(msg->u.s.icntxt);
+       unsigned long flags;
+
+       if (unlikely(context >= i2o_max_drivers)) {
+               osm_warn("%s: Spurious reply to unknown driver %d\n", c->name,
+                        context);
+               return -EIO;
+       }
+
+       spin_lock_irqsave(&i2o_drivers_lock, flags);
+       drv = i2o_drivers[context];
+       spin_unlock_irqrestore(&i2o_drivers_lock, flags);
+
+       if (unlikely(!drv)) {
+               osm_warn("%s: Spurious reply to unknown driver %d\n", c->name,
+                        context);
+               return -EIO;
+       }
+
+       if ((le32_to_cpu(msg->u.head[1]) >> 24) == I2O_CMD_UTIL_EVT_REGISTER) {
+               struct i2o_device *dev, *tmp;
+               struct i2o_event *evt;
+               u16 size;
+               u16 tid = le32_to_cpu(msg->u.head[1]) & 0xfff;
+
+               osm_debug("event received from device %d\n", tid);
+
+               if (!drv->event)
+                       return -EIO;
+
+               /* cut of header from message size (in 32-bit words) */
+               size = (le32_to_cpu(msg->u.head[0]) >> 16) - 5;
+
+               evt = kzalloc(size * 4 + sizeof(*evt), GFP_ATOMIC);
+               if (!evt)
+                       return -ENOMEM;
+
+               evt->size = size;
+               evt->tcntxt = le32_to_cpu(msg->u.s.tcntxt);
+               evt->event_indicator = le32_to_cpu(msg->body[0]);
+               memcpy(&evt->data, &msg->body[1], size * 4);
+
+               list_for_each_entry_safe(dev, tmp, &c->devices, list)
+                   if (dev->lct_data.tid == tid) {
+                       evt->i2o_dev = dev;
+                       break;
+               }
+
+               INIT_WORK(&evt->work, drv->event);
+               queue_work(drv->event_queue, &evt->work);
+               return 1;
+       }
+
+       if (unlikely(!drv->reply)) {
+               osm_debug("%s: Reply to driver %s, but no reply function defined!\n",
+                       c->name, drv->name);
+               return -EIO;
+       }
+
+       return drv->reply(c, m, msg);
+}
+
+/**
+ *     i2o_driver_notify_controller_add_all - Send notify of added controller
+ *     @c: newly added controller
+ *
+ *     Send notifications to all registered drivers that a new controller was
+ *     added.
+ */
+void i2o_driver_notify_controller_add_all(struct i2o_controller *c)
+{
+       int i;
+       struct i2o_driver *drv;
+
+       for (i = 0; i < i2o_max_drivers; i++) {
+               drv = i2o_drivers[i];
+
+               if (drv)
+                       i2o_driver_notify_controller_add(drv, c);
+       }
+}
+
+/**
+ *     i2o_driver_notify_controller_remove_all - Send notify of removed controller
+ *     @c: controller that is being removed
+ *
+ *     Send notifications to all registered drivers that a controller was
+ *     removed.
+ */
+void i2o_driver_notify_controller_remove_all(struct i2o_controller *c)
+{
+       int i;
+       struct i2o_driver *drv;
+
+       for (i = 0; i < i2o_max_drivers; i++) {
+               drv = i2o_drivers[i];
+
+               if (drv)
+                       i2o_driver_notify_controller_remove(drv, c);
+       }
+}
+
+/**
+ *     i2o_driver_notify_device_add_all - Send notify of added device
+ *     @i2o_dev: newly added I2O device
+ *
+ *     Send notifications to all registered drivers that a device was added.
+ */
+void i2o_driver_notify_device_add_all(struct i2o_device *i2o_dev)
+{
+       int i;
+       struct i2o_driver *drv;
+
+       for (i = 0; i < i2o_max_drivers; i++) {
+               drv = i2o_drivers[i];
+
+               if (drv)
+                       i2o_driver_notify_device_add(drv, i2o_dev);
+       }
+}
+
+/**
+ *     i2o_driver_notify_device_remove_all - Send notify of removed device
+ *     @i2o_dev: device that is being removed
+ *
+ *     Send notifications to all registered drivers that a device was removed.
+ */
+void i2o_driver_notify_device_remove_all(struct i2o_device *i2o_dev)
+{
+       int i;
+       struct i2o_driver *drv;
+
+       for (i = 0; i < i2o_max_drivers; i++) {
+               drv = i2o_drivers[i];
+
+               if (drv)
+                       i2o_driver_notify_device_remove(drv, i2o_dev);
+       }
+}
+
+/**
+ *     i2o_driver_init - initialize I2O drivers (OSMs)
+ *
+ *     Registers the I2O bus and allocate memory for the array of OSMs.
+ *
+ *     Returns 0 on success or negative error code on failure.
+ */
+int __init i2o_driver_init(void)
+{
+       int rc = 0;
+
+       spin_lock_init(&i2o_drivers_lock);
+
+       if ((i2o_max_drivers < 2) || (i2o_max_drivers > 64)) {
+               osm_warn("max_drivers set to %d, but must be >=2 and <= 64\n",
+                        i2o_max_drivers);
+               i2o_max_drivers = I2O_MAX_DRIVERS;
+       }
+       osm_info("max drivers = %d\n", i2o_max_drivers);
+
+       i2o_drivers =
+           kcalloc(i2o_max_drivers, sizeof(*i2o_drivers), GFP_KERNEL);
+       if (!i2o_drivers)
+               return -ENOMEM;
+
+       rc = bus_register(&i2o_bus_type);
+
+       if (rc < 0)
+               kfree(i2o_drivers);
+
+       return rc;
+};
+
+/**
+ *     i2o_driver_exit - clean up I2O drivers (OSMs)
+ *
+ *     Unregisters the I2O bus and frees driver array.
+ */
+void i2o_driver_exit(void)
+{
+       bus_unregister(&i2o_bus_type);
+       kfree(i2o_drivers);
+};
+
+EXPORT_SYMBOL(i2o_driver_register);
+EXPORT_SYMBOL(i2o_driver_unregister);
+EXPORT_SYMBOL(i2o_driver_notify_controller_add_all);
+EXPORT_SYMBOL(i2o_driver_notify_controller_remove_all);
+EXPORT_SYMBOL(i2o_driver_notify_device_add_all);
+EXPORT_SYMBOL(i2o_driver_notify_device_remove_all);