- 根目录:
- drivers
- uwb
- lc-rc.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 <linux/slab.h>
#include <linux/export.h>
#include "uwb-internal.h"
static int uwb_rc_index_match(struct device *dev, const void *data)
{
const 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);
/*
* Show the ASIE that is broadcast in the UWB beacon by this uwb_rc device.
*/
static ssize_t ASIE_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct uwb_dev *uwb_dev = to_uwb_dev(dev);
struct uwb_rc *rc = uwb_dev->rc;
struct uwb_ie_hdr *ie;
void *ptr;
size_t len;
int result = 0;
/* init empty buffer. */
result = scnprintf(buf, PAGE_SIZE, "\n");
mutex_lock(&rc->ies_mutex);
/* walk IEData looking for an ASIE. */
ptr = rc->ies->IEData;
len = le16_to_cpu(rc->ies->wIELength);
for (;;) {
ie = uwb_ie_next(&ptr, &len);
if (!ie)
break;
if (ie->element_id == UWB_APP_SPEC_IE) {
result = uwb_ie_dump_hex(ie,
ie->length + sizeof(struct uwb_ie_hdr),
buf, PAGE_SIZE);
break;
}
}
mutex_unlock(&rc->ies_mutex);
return result;
}
/*
* Update the ASIE that is broadcast in the UWB beacon by this uwb_rc device.
*/
static ssize_t ASIE_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_rc *rc = uwb_dev->rc;
char ie_buf[255];
int result, ie_len = 0;
const char *cur_ptr = buf;
struct uwb_ie_hdr *ie;
/* empty string means clear the ASIE. */
if (strlen(buf) <= 1) {
uwb_rc_ie_rm(rc, UWB_APP_SPEC_IE);
return size;
}
/* if non-empty string, convert string of hex chars to binary. */
while (ie_len < sizeof(ie_buf)) {
int char_count;
if (sscanf(cur_ptr, " %02hhX %n",
&(ie_buf[ie_len]), &char_count) > 0) {
++ie_len;
/* skip chars read from cur_ptr. */
cur_ptr += char_count;
} else {
break;
}
}
/* validate IE length and type. */
if (ie_len < sizeof(struct uwb_ie_hdr)) {
dev_err(dev, "%s: Invalid ASIE size %d.\n", __func__, ie_len);
return -EINVAL;
}
ie = (struct uwb_ie_hdr *)ie_buf;
if (ie->element_id != UWB_APP_SPEC_IE) {
dev_err(dev, "%s: Invalid IE element type size = 0x%02X.\n",
__func__, ie->element_id);
return -EINVAL;
}
/* bounds check length field from user. */
if (ie->length > (ie_len - sizeof(struct uwb_ie_hdr)))
ie->length = ie_len - sizeof(struct uwb_ie_hdr);
/*
* Valid ASIE received. Remove current ASIE then add the new one using
* uwb_rc_ie_add.
*/
uwb_rc_ie_rm(rc, UWB_APP_SPEC_IE);
result = uwb_rc_ie_add(rc, ie, ie->length + sizeof(struct uwb_ie_hdr));
return result >= 0 ? size : result;
}
static DEVICE_ATTR_RW(ASIE);
static struct attribute *rc_attrs[] = {
&dev_attr_mac_address.attr,
&dev_attr_scan.attr,
&dev_attr_beacon.attr,
&dev_attr_ASIE.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 administered 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.
*
* _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);
error_rc_start:
uwbd_stop(rc);
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, const void *data)
{
const 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, const void *data)
{
const 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, 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, const void *data)
{
const 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, 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);