/*
* Ultra Wide Band
* Life cycle of devices
*
* Copyright (C) 2005-2006 Intel Corporation
* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
*
* FIXME: docs
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/export.h>
#include <linux/err.h>
#include <linux/kdev_t.h>
#include <linux/random.h>
#include <linux/stat.h>
#include "uwb-internal.h"
/* We initialize addresses to 0xff (invalid, as it is bcast) */
static inline void uwb_dev_addr_init(struct uwb_dev_addr *addr)
{
memset(&addr->data, 0xff, sizeof(addr->data));
}
static inline void uwb_mac_addr_init(struct uwb_mac_addr *addr)
{
memset(&addr->data, 0xff, sizeof(addr->data));
}
/* @returns !0 if a device @addr is a broadcast address */
static inline int uwb_dev_addr_bcast(const struct uwb_dev_addr *addr)
{
static const struct uwb_dev_addr bcast = { .data = { 0xff, 0xff } };
return !uwb_dev_addr_cmp(addr, &bcast);
}
/*
* Add callback @new to be called when an event occurs in @rc.
*/
int uwb_notifs_register(struct uwb_rc *rc, struct uwb_notifs_handler *new)
{
if (mutex_lock_interruptible(&rc->notifs_chain.mutex))
return -ERESTARTSYS;
list_add(&new->list_node, &rc->notifs_chain.list);
mutex_unlock(&rc->notifs_chain.mutex);
return 0;
}
EXPORT_SYMBOL_GPL(uwb_notifs_register);
/*
* Remove event handler (callback)
*/
int uwb_notifs_deregister(struct uwb_rc *rc, struct uwb_notifs_handler *entry)
{
if (mutex_lock_interruptible(&rc->notifs_chain.mutex))
return -ERESTARTSYS;
list_del(&entry->list_node);
mutex_unlock(&rc->notifs_chain.mutex);
return 0;
}
EXPORT_SYMBOL_GPL(uwb_notifs_deregister);
/*
* Notify all event handlers of a given event on @rc
*
* We are called with a valid reference to the device, or NULL if the
* event is not for a particular event (e.g., a BG join event).
*/
void uwb_notify(struct uwb_rc *rc, struct uwb_dev *uwb_dev, enum uwb_notifs event)
{
struct uwb_notifs_handler *handler;
if (mutex_lock_interruptible(&rc->notifs_chain.mutex))
return;
if (!list_empty(&rc->notifs_chain.list)) {
list_for_each_entry(handler, &rc->notifs_chain.list, list_node) {
handler->cb(handler->data, uwb_dev, event);
}
}
mutex_unlock(&rc->notifs_chain.mutex);
}
/*
* Release the backing device of a uwb_dev that has been dynamically allocated.
*/
static void uwb_dev_sys_release(struct device *dev)
{
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
uwb_bce_put(uwb_dev->bce);
memset(uwb_dev, 0x69, sizeof(*uwb_dev));
kfree(uwb_dev);
}
/*
* Initialize a UWB device instance
*
* Alloc, zero and call this function.
*/
void uwb_dev_init(struct uwb_dev *uwb_dev)
{
mutex_init(&uwb_dev->mutex);
device_initialize(&uwb_dev->dev);
uwb_dev->dev.release = uwb_dev_sys_release;
uwb_dev_addr_init(&uwb_dev->dev_addr);
uwb_mac_addr_init(&uwb_dev->mac_addr);
bitmap_fill(uwb_dev->streams, UWB_NUM_GLOBAL_STREAMS);
}
static ssize_t uwb_dev_EUI_48_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
char addr[UWB_ADDR_STRSIZE];
uwb_mac_addr_print(addr, sizeof(addr), &uwb_dev->mac_addr);
return sprintf(buf, "%s\n", addr);
}
static DEVICE_ATTR(EUI_48, S_IRUGO, uwb_dev_EUI_48_show, NULL);
static ssize_t uwb_dev_DevAddr_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
char addr[UWB_ADDR_STRSIZE];
uwb_dev_addr_print(addr, sizeof(addr), &uwb_dev->dev_addr);
return sprintf(buf, "%s\n", addr);
}
static DEVICE_ATTR(DevAddr, S_IRUGO, uwb_dev_DevAddr_show, NULL);
/*
* Show the BPST of this device.
*
* Calculated from the receive time of the device's beacon and it's
* slot number.
*/
static ssize_t uwb_dev_BPST_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
struct uwb_beca_e *bce;
struct uwb_beacon_frame *bf;
u16 bpst;
bce = uwb_dev->bce;
mutex_lock(&bce->mutex);
bf = (struct uwb_beacon_frame *)bce->be->BeaconInfo;
bpst = bce->be->wBPSTOffset
- (u16)(bf->Beacon_Slot_Number * UWB_BEACON_SLOT_LENGTH_US);
mutex_unlock(&bce->mutex);
return sprintf(buf, "%d\n", bpst);
}
static DEVICE_ATTR(BPST, S_IRUGO, uwb_dev_BPST_show, NULL);
/*
* Show the IEs a device is beaconing
*
* We need to access the beacon cache, so we just lock it really
* quick, print the IEs and unlock.
*
* We have a reference on the cache entry, so that should be
* quite safe.
*/
static ssize_t uwb_dev_IEs_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
return uwb_bce_print_IEs(uwb_dev, uwb_dev->bce, buf, PAGE_SIZE);
}
static DEVICE_ATTR(IEs, S_IRUGO | S_IWUSR, uwb_dev_IEs_show, NULL);
static ssize_t uwb_dev_LQE_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
struct uwb_beca_e *bce = uwb_dev->bce;
size_t result;
mutex_lock(&bce->mutex);
result = stats_show(&uwb_dev->bce->lqe_stats, buf);
mutex_unlock(&bce->mutex);
return result;
}
static ssize_t uwb_dev_LQE_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t size)
{
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
struct uwb_beca_e *bce = uwb_dev->bce;
ssize_t result;
mutex_lock(&bce->mutex);
result = stats_store(&uwb_dev->bce->lqe_stats, buf, size);
mutex_unlock(&bce->mutex);
return result;
}
static DEVICE_ATTR(LQE, S_IRUGO | S_IWUSR, uwb_dev_LQE_show, uwb_dev_LQE_store);
static ssize_t uwb_dev_RSSI_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
struct uwb_beca_e *bce = uwb_dev->bce;
size_t result;
mutex_lock(&bce->mutex);
result = stats_show(&uwb_dev->bce->rssi_stats, buf);
mutex_unlock(&bce->mutex);
return result;
}
static ssize_t uwb_dev_RSSI_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t size)
{
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
struct uwb_beca_e *bce = uwb_dev->bce;
ssize_t result;
mutex_lock(&bce->mutex);
result = stats_store(&uwb_dev->bce->rssi_stats, buf, size);
mutex_unlock(&bce->mutex);
return result;
}
static DEVICE_ATTR(RSSI, S_IRUGO | S_IWUSR, uwb_dev_RSSI_show, uwb_dev_RSSI_store);
static struct attribute *dev_attrs[] = {
&dev_attr_EUI_48.attr,
&dev_attr_DevAddr.attr,
&dev_attr_BPST.attr,
&dev_attr_IEs.attr,
&dev_attr_LQE.attr,
&dev_attr_RSSI.attr,
NULL,
};
static struct attribute_group dev_attr_group = {
.attrs = dev_attrs,
};
static const struct attribute_group *groups[] = {
&dev_attr_group,
NULL,
};
/**
* Device SYSFS registration
*
*
*/
static int __uwb_dev_sys_add(struct uwb_dev *uwb_dev, struct device *parent_dev)
{
struct device *dev;
dev = &uwb_dev->dev;
/* Device sysfs files are only useful for neighbor devices not
local radio controllers. */
if (&uwb_dev->rc->uwb_dev != uwb_dev)
dev->groups = groups;
dev->parent = parent_dev;
dev_set_drvdata(dev, uwb_dev);
return device_add(dev);
}
static void __uwb_dev_sys_rm(struct uwb_dev *uwb_dev)
{
dev_set_drvdata(&uwb_dev->dev, NULL);
device_del(&uwb_dev->dev);
}
/**
* Register and initialize a new UWB device
*
* Did you call uwb_dev_init() on it?
*
* @parent_rc: is the parent radio controller who has the link to the
* device. When registering the UWB device that is a UWB
* Radio Controller, we point back to it.
*
* If registering the device that is part of a radio, caller has set
* rc->uwb_dev->dev. Otherwise it is to be left NULL--a new one will
* be allocated.
*/
int uwb_dev_add(struct uwb_dev *uwb_dev, struct device *parent_dev,
struct uwb_rc *parent_rc)
{
int result;
struct device *dev;
BUG_ON(uwb_dev == NULL);
BUG_ON(parent_dev == NULL);
BUG_ON(parent_rc == NULL);
mutex_lock(&uwb_dev->mutex);
dev = &uwb_dev->dev;
uwb_dev->rc = parent_rc;
result = __uwb_dev_sys_add(uwb_dev, parent_dev);
if (result < 0)
printk(KERN_ERR "UWB: unable to register dev %s with sysfs: %d\n",
dev_name(dev), result);
mutex_unlock(&uwb_dev->mutex);
return result;
}
void uwb_dev_rm(struct uwb_dev *uwb_dev)
{
mutex_lock(&uwb_dev->mutex);
__uwb_dev_sys_rm(uwb_dev);
mutex_unlock(&uwb_dev->mutex);
}
static
int __uwb_dev_try_get(struct device *dev, void *__target_uwb_dev)
{
struct uwb_dev *target_uwb_dev = __target_uwb_dev;
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
if (uwb_dev == target_uwb_dev) {
uwb_dev_get(uwb_dev);
return 1;
} else
return 0;
}
/**
* Given a UWB device descriptor, validate and refcount it
*
* @returns NULL if the device does not exist or is quiescing; the ptr to
* it otherwise.
*/
struct uwb_dev *uwb_dev_try_get(struct uwb_rc *rc, struct uwb_dev *uwb_dev)
{
if (uwb_dev_for_each(rc, __uwb_dev_try_get, uwb_dev))
return uwb_dev;
else
return NULL;
}
EXPORT_SYMBOL_GPL(uwb_dev_try_get);
/**
* Remove a device from the system [grunt for other functions]
*/
int __uwb_dev_offair(struct uwb_dev *uwb_dev, struct uwb_rc *rc)
{
struct device *dev = &uwb_dev->dev;
char macbuf[UWB_ADDR_STRSIZE], devbuf[UWB_ADDR_STRSIZE];
uwb_mac_addr_print(macbuf, sizeof(macbuf), &uwb_dev->mac_addr);
uwb_dev_addr_print(devbuf, sizeof(devbuf), &uwb_dev->dev_addr);
dev_info(dev, "uwb device (mac %s dev %s) disconnected from %s %s\n",
macbuf, devbuf,
rc ? rc->uwb_dev.dev.parent->bus->name : "n/a",
rc ? dev_name(rc->uwb_dev.dev.parent) : "");
uwb_dev_rm(uwb_dev);
list_del(&uwb_dev->bce->node);
uwb_bce_put(uwb_dev->bce);
uwb_dev_put(uwb_dev); /* for the creation in _onair() */
return 0;
}
/**
* A device went off the air, clean up after it!
*
* This is called by the UWB Daemon (through the beacon purge function
* uwb_bcn_cache_purge) when it is detected that a device has been in
* radio silence for a while.
*
* If this device is actually a local radio controller we don't need
* to go through the offair process, as it is not registered as that.
*
* NOTE: uwb_bcn_cache.mutex is held!
*/
void uwbd_dev_offair(struct uwb_beca_e *bce)
{
struct uwb_dev *uwb_dev;
uwb_dev = bce->uwb_dev;
if (uwb_dev) {
uwb_notify(uwb_dev->rc, uwb_dev, UWB_NOTIF_OFFAIR);
__uwb_dev_offair(uwb_dev, uwb_dev->rc);
}
}
/**
* A device went on the air, start it up!
*
* This is called by the UWB Daemon when it is detected that a device
* has popped up in the radio range of the radio controller.
*
* It will just create the freaking device, register the beacon and
* stuff and yatla, done.
*
*
* NOTE: uwb_beca.mutex is held, bce->mutex is held
*/
void uwbd_dev_onair(struct uwb_rc *rc, struct uwb_beca_e *bce)
{
int result;
struct device *dev = &rc->uwb_dev.dev;
struct uwb_dev *uwb_dev;
char macbuf[UWB_ADDR_STRSIZE], devbuf[UWB_ADDR_STRSIZE];
uwb_mac_addr_print(macbuf, sizeof(macbuf), bce->mac_addr);
uwb_dev_addr_print(devbuf, sizeof(devbuf), &bce->dev_addr);
uwb_dev = kzalloc(sizeof(struct uwb_dev), GFP_KERNEL);
if (uwb_dev == NULL) {
dev_err(dev, "new device %s: Cannot allocate memory\n",
macbuf);
return;
}
uwb_dev_init(uwb_dev); /* This sets refcnt to one, we own it */
uwb_dev->mac_addr = *bce->mac_addr;
uwb_dev->dev_addr = bce->dev_addr;
dev_set_name(&uwb_dev->dev, macbuf);
result = uwb_dev_add(uwb_dev, &rc->uwb_dev.dev, rc);
if (result < 0) {
dev_err(dev, "new device %s: cannot instantiate device\n",
macbuf);
goto error_dev_add;
}
/* plug the beacon cache */
bce->uwb_dev = uwb_dev;
uwb_dev->bce = bce;
uwb_bce_get(bce); /* released in uwb_dev_sys_release() */
dev_info(dev, "uwb device (mac %s dev %s) connected to %s %s\n",
macbuf, devbuf, rc->uwb_dev.dev.parent->bus->name,
dev_name(rc->uwb_dev.dev.parent));
uwb_notify(rc, uwb_dev, UWB_NOTIF_ONAIR);
return;
error_dev_add:
kfree(uwb_dev);
return;
}
/**
* Iterate over the list of UWB devices, calling a @function on each
*
* See docs for bus_for_each()....
*
* @rc: radio controller for the devices.
* @function: function to call.
* @priv: data to pass to @function.
* @returns: 0 if no invocation of function() returned a value
* different to zero. That value otherwise.
*/
int uwb_dev_for_each(struct uwb_rc *rc, uwb_dev_for_each_f function, void *priv)
{
return device_for_each_child(&rc->uwb_dev.dev, priv, function);
}
EXPORT_SYMBOL_GPL(uwb_dev_for_each);
