/* * 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); 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 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. * * @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); 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);