linux/drivers/uwb/lc-rc.c
David Vrabel 6fae35f9ce uwb: add basic radio manager
The UWB radio manager coordinates the use of the radio between the
PALs that may be using it.  PALs request use of the radio with
uwb_radio_start() and the radio manager will start beaconing if its
not already doing so.  When the last PAL has called uwb_radio_stop()
beaconing will be stopped.

In the future, the radio manager will have a more sophisticated channel
selection algorithm, probably following the Channel Selection Policy
from the WiMedia Alliance when it is finalized.  For now, channel 9
(BG1, TFC1) is selected.

The user may override the channel selected by the radio manager and may
force the radio to stop beaconing.

The WUSB Host Controller PAL makes use of this and there are two new
debug PAL commands that can be used for testing.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
2008-11-19 14:46:33 +00:00

473 lines
11 KiB
C

/*
* Ultra Wide Band
* Life cycle of radio controllers
*
* 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
*
* A UWB radio controller is also a UWB device, so it embeds one...
*
* List of RCs comes from the 'struct class uwb_rc_class'.
*/
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/random.h>
#include <linux/kdev_t.h>
#include <linux/etherdevice.h>
#include <linux/usb.h>
#include "uwb-internal.h"
static int uwb_rc_index_match(struct device *dev, void *data)
{
int *index = data;
struct uwb_rc *rc = dev_get_drvdata(dev);
if (rc->index == *index)
return 1;
return 0;
}
static struct uwb_rc *uwb_rc_find_by_index(int index)
{
struct device *dev;
struct uwb_rc *rc = NULL;
dev = class_find_device(&uwb_rc_class, NULL, &index, uwb_rc_index_match);
if (dev)
rc = dev_get_drvdata(dev);
return rc;
}
static int uwb_rc_new_index(void)
{
int index = 0;
for (;;) {
if (!uwb_rc_find_by_index(index))
return index;
if (++index < 0)
index = 0;
}
}
/**
* Release the backing device of a uwb_rc that has been dynamically allocated.
*/
static void uwb_rc_sys_release(struct device *dev)
{
struct uwb_dev *uwb_dev = container_of(dev, struct uwb_dev, dev);
struct uwb_rc *rc = container_of(uwb_dev, struct uwb_rc, uwb_dev);
uwb_rc_ie_release(rc);
kfree(rc);
}
void uwb_rc_init(struct uwb_rc *rc)
{
struct uwb_dev *uwb_dev = &rc->uwb_dev;
uwb_dev_init(uwb_dev);
rc->uwb_dev.dev.class = &uwb_rc_class;
rc->uwb_dev.dev.release = uwb_rc_sys_release;
uwb_rc_neh_create(rc);
rc->beaconing = -1;
rc->scan_type = UWB_SCAN_DISABLED;
INIT_LIST_HEAD(&rc->notifs_chain.list);
mutex_init(&rc->notifs_chain.mutex);
INIT_LIST_HEAD(&rc->uwb_beca.list);
mutex_init(&rc->uwb_beca.mutex);
uwb_drp_avail_init(rc);
uwb_rc_ie_init(rc);
uwb_rsv_init(rc);
uwb_rc_pal_init(rc);
}
EXPORT_SYMBOL_GPL(uwb_rc_init);
struct uwb_rc *uwb_rc_alloc(void)
{
struct uwb_rc *rc;
rc = kzalloc(sizeof(*rc), GFP_KERNEL);
if (rc == NULL)
return NULL;
uwb_rc_init(rc);
return rc;
}
EXPORT_SYMBOL_GPL(uwb_rc_alloc);
static struct attribute *rc_attrs[] = {
&dev_attr_mac_address.attr,
&dev_attr_scan.attr,
&dev_attr_beacon.attr,
NULL,
};
static struct attribute_group rc_attr_group = {
.attrs = rc_attrs,
};
/*
* Registration of sysfs specific stuff
*/
static int uwb_rc_sys_add(struct uwb_rc *rc)
{
return sysfs_create_group(&rc->uwb_dev.dev.kobj, &rc_attr_group);
}
static void __uwb_rc_sys_rm(struct uwb_rc *rc)
{
sysfs_remove_group(&rc->uwb_dev.dev.kobj, &rc_attr_group);
}
/**
* uwb_rc_mac_addr_setup - get an RC's EUI-48 address or set it
* @rc: the radio controller.
*
* If the EUI-48 address is 00:00:00:00:00:00 or FF:FF:FF:FF:FF:FF
* then a random locally administered EUI-48 is generated and set on
* the device. The probability of address collisions is sufficiently
* unlikely (1/2^40 = 9.1e-13) that they're not checked for.
*/
static
int uwb_rc_mac_addr_setup(struct uwb_rc *rc)
{
int result;
struct device *dev = &rc->uwb_dev.dev;
struct uwb_dev *uwb_dev = &rc->uwb_dev;
char devname[UWB_ADDR_STRSIZE];
struct uwb_mac_addr addr;
result = uwb_rc_mac_addr_get(rc, &addr);
if (result < 0) {
dev_err(dev, "cannot retrieve UWB EUI-48 address: %d\n", result);
return result;
}
if (uwb_mac_addr_unset(&addr) || uwb_mac_addr_bcast(&addr)) {
addr.data[0] = 0x02; /* locally adminstered and unicast */
get_random_bytes(&addr.data[1], sizeof(addr.data)-1);
result = uwb_rc_mac_addr_set(rc, &addr);
if (result < 0) {
uwb_mac_addr_print(devname, sizeof(devname), &addr);
dev_err(dev, "cannot set EUI-48 address %s: %d\n",
devname, result);
return result;
}
}
uwb_dev->mac_addr = addr;
return 0;
}
static int uwb_rc_setup(struct uwb_rc *rc)
{
int result;
struct device *dev = &rc->uwb_dev.dev;
result = uwb_radio_setup(rc);
if (result < 0) {
dev_err(dev, "cannot setup UWB radio: %d\n", result);
goto error;
}
result = uwb_rc_mac_addr_setup(rc);
if (result < 0) {
dev_err(dev, "cannot setup UWB MAC address: %d\n", result);
goto error;
}
result = uwb_rc_dev_addr_assign(rc);
if (result < 0) {
dev_err(dev, "cannot assign UWB DevAddr: %d\n", result);
goto error;
}
result = uwb_rc_ie_setup(rc);
if (result < 0) {
dev_err(dev, "cannot setup IE subsystem: %d\n", result);
goto error_ie_setup;
}
result = uwb_rsv_setup(rc);
if (result < 0) {
dev_err(dev, "cannot setup reservation subsystem: %d\n", result);
goto error_rsv_setup;
}
uwb_dbg_add_rc(rc);
return 0;
error_rsv_setup:
uwb_rc_ie_release(rc);
error_ie_setup:
error:
return result;
}
/**
* Register a new UWB radio controller
*
* Did you call uwb_rc_init() on your rc?
*
* We assume that this is being called with a > 0 refcount on
* it [through ops->{get|put}_device(). We'll take our own, though.
*
* @parent_dev is our real device, the one that provides the actual UWB device
*/
int uwb_rc_add(struct uwb_rc *rc, struct device *parent_dev, void *priv)
{
int result;
struct device *dev;
char macbuf[UWB_ADDR_STRSIZE], devbuf[UWB_ADDR_STRSIZE];
rc->index = uwb_rc_new_index();
dev = &rc->uwb_dev.dev;
dev_set_name(dev, "uwb%d", rc->index);
rc->priv = priv;
init_waitqueue_head(&rc->uwbd.wq);
INIT_LIST_HEAD(&rc->uwbd.event_list);
spin_lock_init(&rc->uwbd.event_list_lock);
uwbd_start(rc);
result = rc->start(rc);
if (result < 0)
goto error_rc_start;
result = uwb_rc_setup(rc);
if (result < 0) {
dev_err(dev, "cannot setup UWB radio controller: %d\n", result);
goto error_rc_setup;
}
result = uwb_dev_add(&rc->uwb_dev, parent_dev, rc);
if (result < 0 && result != -EADDRNOTAVAIL)
goto error_dev_add;
result = uwb_rc_sys_add(rc);
if (result < 0) {
dev_err(parent_dev, "cannot register UWB radio controller "
"dev attributes: %d\n", result);
goto error_sys_add;
}
uwb_mac_addr_print(macbuf, sizeof(macbuf), &rc->uwb_dev.mac_addr);
uwb_dev_addr_print(devbuf, sizeof(devbuf), &rc->uwb_dev.dev_addr);
dev_info(dev,
"new uwb radio controller (mac %s dev %s) on %s %s\n",
macbuf, devbuf, parent_dev->bus->name, dev_name(parent_dev));
rc->ready = 1;
return 0;
error_sys_add:
uwb_dev_rm(&rc->uwb_dev);
error_dev_add:
error_rc_setup:
rc->stop(rc);
uwbd_stop(rc);
error_rc_start:
return result;
}
EXPORT_SYMBOL_GPL(uwb_rc_add);
static int uwb_dev_offair_helper(struct device *dev, void *priv)
{
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
return __uwb_dev_offair(uwb_dev, uwb_dev->rc);
}
/*
* Remove a Radio Controller; stop beaconing/scanning, disconnect all children
*/
void uwb_rc_rm(struct uwb_rc *rc)
{
rc->ready = 0;
uwb_dbg_del_rc(rc);
uwb_rsv_remove_all(rc);
uwb_radio_shutdown(rc);
rc->stop(rc);
uwbd_stop(rc);
uwb_rc_neh_destroy(rc);
uwb_dev_lock(&rc->uwb_dev);
rc->priv = NULL;
rc->cmd = NULL;
uwb_dev_unlock(&rc->uwb_dev);
mutex_lock(&rc->uwb_beca.mutex);
uwb_dev_for_each(rc, uwb_dev_offair_helper, NULL);
__uwb_rc_sys_rm(rc);
mutex_unlock(&rc->uwb_beca.mutex);
uwb_rsv_cleanup(rc);
uwb_beca_release(rc);
uwb_dev_rm(&rc->uwb_dev);
}
EXPORT_SYMBOL_GPL(uwb_rc_rm);
static int find_rc_try_get(struct device *dev, void *data)
{
struct uwb_rc *target_rc = data;
struct uwb_rc *rc = dev_get_drvdata(dev);
if (rc == NULL) {
WARN_ON(1);
return 0;
}
if (rc == target_rc) {
if (rc->ready == 0)
return 0;
else
return 1;
}
return 0;
}
/**
* Given a radio controller descriptor, validate and refcount it
*
* @returns NULL if the rc does not exist or is quiescing; the ptr to
* it otherwise.
*/
struct uwb_rc *__uwb_rc_try_get(struct uwb_rc *target_rc)
{
struct device *dev;
struct uwb_rc *rc = NULL;
dev = class_find_device(&uwb_rc_class, NULL, target_rc,
find_rc_try_get);
if (dev) {
rc = dev_get_drvdata(dev);
__uwb_rc_get(rc);
}
return rc;
}
EXPORT_SYMBOL_GPL(__uwb_rc_try_get);
/*
* RC get for external refcount acquirers...
*
* Increments the refcount of the device and it's backend modules
*/
static inline struct uwb_rc *uwb_rc_get(struct uwb_rc *rc)
{
if (rc->ready == 0)
return NULL;
uwb_dev_get(&rc->uwb_dev);
return rc;
}
static int find_rc_grandpa(struct device *dev, void *data)
{
struct device *grandpa_dev = data;
struct uwb_rc *rc = dev_get_drvdata(dev);
if (rc->uwb_dev.dev.parent->parent == grandpa_dev) {
rc = uwb_rc_get(rc);
return 1;
}
return 0;
}
/**
* Locate and refcount a radio controller given a common grand-parent
*
* @grandpa_dev Pointer to the 'grandparent' device structure.
* @returns NULL If the rc does not exist or is quiescing; the ptr to
* it otherwise, properly referenced.
*
* The Radio Control interface (or the UWB Radio Controller) is always
* an interface of a device. The parent is the interface, the
* grandparent is the device that encapsulates the interface.
*
* There is no need to lock around as the "grandpa" would be
* refcounted by the target, and to remove the referemes, the
* uwb_rc_class->sem would have to be taken--we hold it, ergo we
* should be safe.
*/
struct uwb_rc *uwb_rc_get_by_grandpa(const struct device *grandpa_dev)
{
struct device *dev;
struct uwb_rc *rc = NULL;
dev = class_find_device(&uwb_rc_class, NULL, (void *)grandpa_dev,
find_rc_grandpa);
if (dev)
rc = dev_get_drvdata(dev);
return rc;
}
EXPORT_SYMBOL_GPL(uwb_rc_get_by_grandpa);
/**
* Find a radio controller by device address
*
* @returns the pointer to the radio controller, properly referenced
*/
static int find_rc_dev(struct device *dev, void *data)
{
struct uwb_dev_addr *addr = data;
struct uwb_rc *rc = dev_get_drvdata(dev);
if (rc == NULL) {
WARN_ON(1);
return 0;
}
if (!uwb_dev_addr_cmp(&rc->uwb_dev.dev_addr, addr)) {
rc = uwb_rc_get(rc);
return 1;
}
return 0;
}
struct uwb_rc *uwb_rc_get_by_dev(const struct uwb_dev_addr *addr)
{
struct device *dev;
struct uwb_rc *rc = NULL;
dev = class_find_device(&uwb_rc_class, NULL, (void *)addr,
find_rc_dev);
if (dev)
rc = dev_get_drvdata(dev);
return rc;
}
EXPORT_SYMBOL_GPL(uwb_rc_get_by_dev);
/**
* Drop a reference on a radio controller
*
* This is the version that should be done by entities external to the
* UWB Radio Control stack (ie: clients of the API).
*/
void uwb_rc_put(struct uwb_rc *rc)
{
__uwb_rc_put(rc);
}
EXPORT_SYMBOL_GPL(uwb_rc_put);