uwb: add the UWB stack (MLME)

Most of the MAC Layer Management Entity (MLME) support: address, beacon, IE
and scan management.

Signed-off-by: David Vrabel <david.vrabel@csr.com>

1 files changed, 374 insertions, 0 deletions

diff --git a/drivers/uwb/address.c b/drivers/uwb/address.c
new file mode 100644
index 00000000000..1664ae5f170
--- /dev/null
+++ b/drivers/uwb/address.c
@@ -0,0 +1,374 @@
+/*
+ * Ultra Wide Band
+ * Address management
+ *
+ * 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/errno.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/random.h>
+#include <linux/etherdevice.h>
+#include <linux/uwb/debug.h>
+#include "uwb-internal.h"
+
+
+/** Device Address Management command */
+struct uwb_rc_cmd_dev_addr_mgmt {
+        struct uwb_rccb rccb;
+        u8 bmOperationType;
+        u8 baAddr[6];
+} __attribute__((packed));
+
+
+/**
+ * Low level command for setting/getting UWB radio's addresses
+ *
+ * @hwarc:      HWA Radio Control interface instance
+ * @bmOperationType:
+ *              Set/get, MAC/DEV (see WUSB1.0[8.6.2.2])
+ * @baAddr:     address buffer--assumed to have enough data to hold
+ *              the address type requested.
+ * @reply:      Pointer to reply buffer (can be stack allocated)
+ * @returns:    0 if ok, < 0 errno code on error.
+ *
+ * @cmd has to be allocated because USB cannot grok USB or vmalloc
+ * buffers depending on your combination of host architecture.
+ */
+static
+int uwb_rc_dev_addr_mgmt(struct uwb_rc *rc,
+                         u8 bmOperationType, const u8 *baAddr,
+                         struct uwb_rc_evt_dev_addr_mgmt *reply)
+{
+        int result;
+        struct uwb_rc_cmd_dev_addr_mgmt *cmd;
+
+        result = -ENOMEM;
+        cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
+        if (cmd == NULL)
+                goto error_kzalloc;
+        cmd->rccb.bCommandType = UWB_RC_CET_GENERAL;
+        cmd->rccb.wCommand = cpu_to_le16(UWB_RC_CMD_DEV_ADDR_MGMT);
+        cmd->bmOperationType = bmOperationType;
+        if (baAddr) {
+                size_t size = 0;
+                switch (bmOperationType >> 1) {
+                case 0: size = 2; break;
+                case 1: size = 6; break;
+                default: BUG();
+                }
+                memcpy(cmd->baAddr, baAddr, size);
+        }
+        reply->rceb.bEventType = UWB_RC_CET_GENERAL;
+        reply->rceb.wEvent = UWB_RC_CMD_DEV_ADDR_MGMT;
+        result = uwb_rc_cmd(rc, "DEV-ADDR-MGMT",
+                            &cmd->rccb, sizeof(*cmd),
+                            &reply->rceb, sizeof(*reply));
+        if (result < 0)
+                goto error_cmd;
+        if (result < sizeof(*reply)) {
+                dev_err(&rc->uwb_dev.dev,
+                        "DEV-ADDR-MGMT: not enough data replied: "
+                        "%d vs %zu bytes needed\n", result, sizeof(*reply));
+                result = -ENOMSG;
+        } else if (reply->bResultCode != UWB_RC_RES_SUCCESS) {
+                dev_err(&rc->uwb_dev.dev,
+                        "DEV-ADDR-MGMT: command execution failed: %s (%d)\n",
+                        uwb_rc_strerror(reply->bResultCode),
+                        reply->bResultCode);
+                result = -EIO;
+        } else
+                result = 0;
+error_cmd:
+        kfree(cmd);
+error_kzalloc:
+        return result;
+}
+
+
+/**
+ * Set the UWB RC MAC or device address.
+ *
+ * @rc:      UWB Radio Controller
+ * @_addr:   Pointer to address to write [assumed to be either a
+ *           'struct uwb_mac_addr *' or a 'struct uwb_dev_addr *'].
+ * @type:    Type of address to set (UWB_ADDR_DEV or UWB_ADDR_MAC).
+ * @returns: 0 if ok, < 0 errno code on error.
+ *
+ * Some anal retentivity here: even if both 'struct
+ * uwb_{dev,mac}_addr' have the actual byte array in the same offset
+ * and I could just pass _addr to hwarc_cmd_dev_addr_mgmt(), I prefer
+ * to use some syntatic sugar in case someday we decide to change the
+ * format of the structs. The compiler will optimize it out anyway.
+ */
+static int uwb_rc_addr_set(struct uwb_rc *rc,
+                    const void *_addr, enum uwb_addr_type type)
+{
+        int result;
+        u8 bmOperationType = 0x1;               /* Set address */
+        const struct uwb_dev_addr *dev_addr = _addr;
+        const struct uwb_mac_addr *mac_addr = _addr;
+        struct uwb_rc_evt_dev_addr_mgmt reply;
+        const u8 *baAddr;
+
+        result = -EINVAL;
+        switch (type) {
+        case UWB_ADDR_DEV:
+                baAddr = dev_addr->data;
+                break;
+        case UWB_ADDR_MAC:
+                baAddr = mac_addr->data;
+                bmOperationType |= 0x2;
+                break;
+        default:
+                return result;
+        }
+        return uwb_rc_dev_addr_mgmt(rc, bmOperationType, baAddr, &reply);
+}
+
+
+/**
+ * Get the UWB radio's MAC or device address.
+ *
+ * @rc:      UWB Radio Controller
+ * @_addr:   Where to write the address data [assumed to be either a
+ *           'struct uwb_mac_addr *' or a 'struct uwb_dev_addr *'].
+ * @type:    Type of address to get (UWB_ADDR_DEV or UWB_ADDR_MAC).
+ * @returns: 0 if ok (and *_addr set), < 0 errno code on error.
+ *
+ * See comment in uwb_rc_addr_set() about anal retentivity in the
+ * type handling of the address variables.
+ */
+static int uwb_rc_addr_get(struct uwb_rc *rc,
+                    void *_addr, enum uwb_addr_type type)
+{
+        int result;
+        u8 bmOperationType = 0x0;               /* Get address */
+        struct uwb_rc_evt_dev_addr_mgmt evt;
+        struct uwb_dev_addr *dev_addr = _addr;
+        struct uwb_mac_addr *mac_addr = _addr;
+        u8 *baAddr;
+
+        result = -EINVAL;
+        switch (type) {
+        case UWB_ADDR_DEV:
+                baAddr = dev_addr->data;
+                break;
+        case UWB_ADDR_MAC:
+                bmOperationType |= 0x2;
+                baAddr = mac_addr->data;
+                break;
+        default:
+                return result;
+        }
+        result = uwb_rc_dev_addr_mgmt(rc, bmOperationType, baAddr, &evt);
+        if (result == 0)
+                switch (type) {
+                case UWB_ADDR_DEV:
+                        memcpy(&dev_addr->data, evt.baAddr,
+                               sizeof(dev_addr->data));
+                        break;
+                case UWB_ADDR_MAC:
+                        memcpy(&mac_addr->data, evt.baAddr,
+                               sizeof(mac_addr->data));
+                        break;
+                default:                /* shut gcc up */
+                        BUG();
+                }
+        return result;
+}
+
+
+/** Get @rc's MAC address to @addr */
+int uwb_rc_mac_addr_get(struct uwb_rc *rc,
+                        struct uwb_mac_addr *addr) {
+        return uwb_rc_addr_get(rc, addr, UWB_ADDR_MAC);
+}
+EXPORT_SYMBOL_GPL(uwb_rc_mac_addr_get);
+
+
+/** Get @rc's device address to @addr */
+int uwb_rc_dev_addr_get(struct uwb_rc *rc,
+                        struct uwb_dev_addr *addr) {
+        return uwb_rc_addr_get(rc, addr, UWB_ADDR_DEV);
+}
+EXPORT_SYMBOL_GPL(uwb_rc_dev_addr_get);
+
+
+/** Set @rc's address to @addr */
+int uwb_rc_mac_addr_set(struct uwb_rc *rc,
+                        const struct uwb_mac_addr *addr)
+{
+        int result = -EINVAL;
+        mutex_lock(&rc->uwb_dev.mutex);
+        result = uwb_rc_addr_set(rc, addr, UWB_ADDR_MAC);
+        mutex_unlock(&rc->uwb_dev.mutex);
+        return result;
+}
+
+
+/** Set @rc's address to @addr */
+int uwb_rc_dev_addr_set(struct uwb_rc *rc,
+                        const struct uwb_dev_addr *addr)
+{
+        int result = -EINVAL;
+        mutex_lock(&rc->uwb_dev.mutex);
+        result = uwb_rc_addr_set(rc, addr, UWB_ADDR_DEV);
+        rc->uwb_dev.dev_addr = *addr;
+        mutex_unlock(&rc->uwb_dev.mutex);
+        return result;
+}
+
+/* Returns !0 if given address is already assigned to device. */
+int __uwb_mac_addr_assigned_check(struct device *dev, void *_addr)
+{
+        struct uwb_dev *uwb_dev = to_uwb_dev(dev);
+        struct uwb_mac_addr *addr = _addr;
+
+        if (!uwb_mac_addr_cmp(addr, &uwb_dev->mac_addr))
+                return !0;
+        return 0;
+}
+
+/* Returns !0 if given address is already assigned to device. */
+int __uwb_dev_addr_assigned_check(struct device *dev, void *_addr)
+{
+        struct uwb_dev *uwb_dev = to_uwb_dev(dev);
+        struct uwb_dev_addr *addr = _addr;
+        if (!uwb_dev_addr_cmp(addr, &uwb_dev->dev_addr))
+                return !0;
+        return 0;
+}
+
+/**
+ * uwb_dev_addr_assign - assigned a generated DevAddr to a radio controller
+ * @rc:      the (local) radio controller device requiring a new DevAddr
+ *
+ * A new DevAddr is required when:
+ *    - first setting up a radio controller
+ *    - if the hardware reports a DevAddr conflict
+ *
+ * The DevAddr is randomly generated in the generated DevAddr range
+ * [0x100, 0xfeff]. The number of devices in a beacon group is limited
+ * by mMaxBPLength (96) so this address space will never be exhausted.
+ *
+ * [ECMA-368] 17.1.1, 17.16.
+ */
+int uwb_rc_dev_addr_assign(struct uwb_rc *rc)
+{
+        struct uwb_dev_addr new_addr;
+
+        do {
+                get_random_bytes(new_addr.data, sizeof(new_addr.data));
+        } while (new_addr.data[0] == 0x00 || new_addr.data[0] == 0xff
+                 || __uwb_dev_addr_assigned(rc, &new_addr));
+
+        return uwb_rc_dev_addr_set(rc, &new_addr);
+}
+
+/**
+ * uwbd_evt_handle_rc_dev_addr_conflict - handle a DEV_ADDR_CONFLICT event
+ * @evt: the DEV_ADDR_CONFLICT notification from the radio controller
+ *
+ * A new (non-conflicting) DevAddr is assigned to the radio controller.
+ *
+ * [ECMA-368] 17.1.1.1.
+ */
+int uwbd_evt_handle_rc_dev_addr_conflict(struct uwb_event *evt)
+{
+        struct uwb_rc *rc = evt->rc;
+
+        return uwb_rc_dev_addr_assign(rc);
+}
+
+/*
+ * Print the 48-bit EUI MAC address of the radio controller when
+ * reading /sys/class/uwb_rc/XX/mac_address
+ */
+static ssize_t uwb_rc_mac_addr_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_mac_addr addr;
+        ssize_t result;
+
+        mutex_lock(&rc->uwb_dev.mutex);
+        result = uwb_rc_addr_get(rc, &addr, UWB_ADDR_MAC);
+        mutex_unlock(&rc->uwb_dev.mutex);
+        if (result >= 0) {
+                result = uwb_mac_addr_print(buf, UWB_ADDR_STRSIZE, &addr);
+                buf[result++] = '\n';
+        }
+        return result;
+}
+
+/*
+ * Parse a 48 bit address written to /sys/class/uwb_rc/XX/mac_address
+ * and if correct, set it.
+ */
+static ssize_t uwb_rc_mac_addr_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;
+        struct uwb_mac_addr addr;
+        ssize_t result;
+
+        result = sscanf(buf, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx\n",
+                        &addr.data[0], &addr.data[1], &addr.data[2],
+                        &addr.data[3], &addr.data[4], &addr.data[5]);
+        if (result != 6) {
+                result = -EINVAL;
+                goto out;
+        }
+        if (is_multicast_ether_addr(addr.data)) {
+                dev_err(&rc->uwb_dev.dev, "refusing to set multicast "
+                        "MAC address %s\n", buf);
+                result = -EINVAL;
+                goto out;
+        }
+        result = uwb_rc_mac_addr_set(rc, &addr);
+        if (result == 0)
+                rc->uwb_dev.mac_addr = addr;
+out:
+        return result < 0 ? result : size;
+}
+DEVICE_ATTR(mac_address, S_IRUGO | S_IWUSR, uwb_rc_mac_addr_show, uwb_rc_mac_addr_store);
+
+/** Print @addr to @buf, @return bytes written */
+size_t __uwb_addr_print(char *buf, size_t buf_size, const unsigned char *addr,
+                        int type)
+{
+        size_t result;
+        if (type)
+                result = scnprintf(buf, buf_size,
+                                  "%02x:%02x:%02x:%02x:%02x:%02x",
+                                  addr[0], addr[1], addr[2],
+                                  addr[3], addr[4], addr[5]);
+        else
+                result = scnprintf(buf, buf_size, "%02x:%02x",
+                                  addr[1], addr[0]);
+        return result;
+}
+EXPORT_SYMBOL_GPL(__uwb_addr_print);