uwb: add the UWB stack (MLME)

/*

 * 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);

/*

 * Ultra Wide Band

 * Scanning 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

 * FIXME: there are issues here on how BEACON and SCAN on USB RCI deal

 *        with each other. Currently seems that START_BEACON while

 *        SCAN_ONLY will cancel the scan, so we need to update the

 *        state here. Clarification request sent by email on

 *        10/05/2005.

 *        10/28/2005 No clear answer heard--maybe we'll hack the API

 *                   so that when we start beaconing, if the HC is

 *                   scanning in a mode not compatible with beaconing

 *                   we just fail.

 */

#include <linux/device.h>

#include <linux/err.h>

#include "uwb-internal.h"

/**

 * Start/stop scanning in a radio controller

 *

 * @rc:      UWB Radio Controlller

 * @channel: Channel to scan; encodings in WUSB1.0[Table 5.12]

 * @type:    Type of scanning to do.

 * @bpst_offset: value at which to start scanning (if type ==

 *                UWB_SCAN_ONLY_STARTTIME)

 * @returns: 0 if ok, < 0 errno code on error

 *

 * We put the command on kmalloc'ed memory as some arches cannot do

 * USB from the stack. The reply event is copied from an stage buffer,

 * so it can be in the stack. See WUSB1.0[8.6.2.4] for more details.

 */

int uwb_rc_scan(struct uwb_rc *rc,

		unsigned channel, enum uwb_scan_type type,

		unsigned bpst_offset)

{

	int result;

	struct uwb_rc_cmd_scan *cmd;

	struct uwb_rc_evt_confirm reply;

	result = -ENOMEM;

	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);

	if (cmd == NULL)

		goto error_kzalloc;

	mutex_lock(&rc->uwb_dev.mutex);

	cmd->rccb.bCommandType = UWB_RC_CET_GENERAL;

	cmd->rccb.wCommand = cpu_to_le16(UWB_RC_CMD_SCAN);

	cmd->bChannelNumber = channel;

	cmd->bScanState = type;

	cmd->wStartTime = cpu_to_le16(bpst_offset);

	reply.rceb.bEventType = UWB_RC_CET_GENERAL;

	reply.rceb.wEvent = UWB_RC_CMD_SCAN;

	result = uwb_rc_cmd(rc, "SCAN", &cmd->rccb, sizeof(*cmd),

			    &reply.rceb, sizeof(reply));

	if (result < 0)

		goto error_cmd;

	if (reply.bResultCode != UWB_RC_RES_SUCCESS) {

		dev_err(&rc->uwb_dev.dev,

			"SCAN: command execution failed: %s (%d)\n",

			uwb_rc_strerror(reply.bResultCode), reply.bResultCode);

		result = -EIO;

		goto error_cmd;

	}

	rc->scanning = channel;

	rc->scan_type = type;

error_cmd:

	mutex_unlock(&rc->uwb_dev.mutex);

	kfree(cmd);

error_kzalloc:

	return result;

}

/*

 * Print scanning state

 */

static ssize_t uwb_rc_scan_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;

	ssize_t result;

	mutex_lock(&rc->uwb_dev.mutex);

	result = sprintf(buf, "%d %d\n", rc->scanning, rc->scan_type);

	mutex_unlock(&rc->uwb_dev.mutex);

	return result;

}

/*

 *

 */

static ssize_t uwb_rc_scan_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;

	unsigned channel;

	unsigned type;

	unsigned bpst_offset = 0;

	ssize_t result = -EINVAL;

	result = sscanf(buf, "%u %u %u\n", &channel, &type, &bpst_offset);

	if (result >= 2 && type < UWB_SCAN_TOP)

		result = uwb_rc_scan(rc, channel, type, bpst_offset);

	return result < 0 ? result : size;

}

/** Radio Control sysfs interface (declaration) */

DEVICE_ATTR(scan, S_IRUGO | S_IWUSR, uwb_rc_scan_show, uwb_rc_scan_store);