diff options
Diffstat (limited to 'drivers/uwb/lc-rc.c')
-rw-r--r-- | drivers/uwb/lc-rc.c | 583 |
1 files changed, 583 insertions, 0 deletions
diff --git a/drivers/uwb/lc-rc.c b/drivers/uwb/lc-rc.c new file mode 100644 index 000000000..b0816c753 --- /dev/null +++ b/drivers/uwb/lc-rc.c @@ -0,0 +1,583 @@ +/* + * 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); + put_device(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 const 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); + put_device(dev); + } + + 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); + put_device(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); + put_device(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); |