diff options
Diffstat (limited to 'drivers/message/i2o/driver.c')
-rw-r--r-- | drivers/message/i2o/driver.c | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/drivers/message/i2o/driver.c b/drivers/message/i2o/driver.c new file mode 100644 index 000000000000..91f4edbb2a27 --- /dev/null +++ b/drivers/message/i2o/driver.c @@ -0,0 +1,374 @@ +/* + * 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 <linux/i2o.h> + +/* max_drivers - Maximum I2O drivers (OSMs) which could be registered */ +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 a I2O device class id match 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, +}; + +/** + * 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; + + pr_debug("i2o: Register driver %s\n", drv->name); + + if (drv->event) { + drv->event_queue = create_workqueue(drv->name); + if (!drv->event_queue) { + printk(KERN_ERR "i2o: Could not initialize event queue " + "for driver %s\n", drv->name); + return -EFAULT; + } + pr_debug("i2o: 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) { + printk(KERN_ERR "i2o: too many drivers registered, " + "increase max_drivers\n"); + spin_unlock_irqrestore(&i2o_drivers_lock, flags); + return -EFAULT; + } + + drv->context = i; + i2o_drivers[i] = drv; + + spin_unlock_irqrestore(&i2o_drivers_lock, flags); + + pr_debug("i2o: 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) + destroy_workqueue(drv->event_queue); + + 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; + + pr_debug("i2o: 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; + pr_debug("i2o: 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 + * @msg: I2O message to be delivered + * + * 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_message __iomem *msg) +{ + struct i2o_driver *drv; + u32 context = readl(&msg->u.s.icntxt); + + if (likely(context < i2o_max_drivers)) { + spin_lock(&i2o_drivers_lock); + drv = i2o_drivers[context]; + spin_unlock(&i2o_drivers_lock); + + if (unlikely(!drv)) { + printk(KERN_WARNING "%s: Spurious reply to unknown " + "driver %d\n", c->name, context); + return -EIO; + } + + if ((readl(&msg->u.head[1]) >> 24) == I2O_CMD_UTIL_EVT_REGISTER) { + struct i2o_device *dev, *tmp; + struct i2o_event *evt; + u16 size; + u16 tid; + + tid = readl(&msg->u.head[1]) & 0x1fff; + + pr_debug("%s: event received from device %d\n", c->name, + tid); + + /* cut of header from message size (in 32-bit words) */ + size = (readl(&msg->u.head[0]) >> 16) - 5; + + evt = kmalloc(size * 4 + sizeof(*evt), GFP_ATOMIC); + if (!evt) + return -ENOMEM; + memset(evt, 0, size * 4 + sizeof(*evt)); + + evt->size = size; + memcpy_fromio(&evt->tcntxt, &msg->u.s.tcntxt, + (size + 2) * 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, (void (*)(void *))drv->event, + evt); + queue_work(drv->event_queue, &evt->work); + return 1; + } + + if (likely(drv->reply)) + return drv->reply(c, m, msg); + else + pr_debug("%s: Reply to driver %s, but no reply function" + " defined!\n", c->name, drv->name); + return -EIO; + } else + printk(KERN_WARNING "%s: Spurious reply to unknown driver " + "%d\n", c->name, readl(&msg->u.s.icntxt)); + return -EIO; +} + +/** + * i2o_driver_notify_controller_add_all - Send notify of added controller + * to all I2O drivers + * + * 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 to all I2O drivers + * + * 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 to all + * I2O drivers + * + * 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 to + * all I2O drivers + * + * 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) || + ((i2o_max_drivers ^ (i2o_max_drivers - 1)) != + (2 * i2o_max_drivers - 1))) { + printk(KERN_WARNING "i2o: max_drivers set to %d, but must be " + ">=2 and <= 64 and a power of 2\n", i2o_max_drivers); + i2o_max_drivers = I2O_MAX_DRIVERS; + } + printk(KERN_INFO "i2o: max drivers = %d\n", i2o_max_drivers); + + i2o_drivers = + kmalloc(i2o_max_drivers * sizeof(*i2o_drivers), GFP_KERNEL); + if (!i2o_drivers) + return -ENOMEM; + + memset(i2o_drivers, 0, i2o_max_drivers * sizeof(*i2o_drivers)); + + 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 free driver array. + */ +void __exit 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); |