summaryrefslogtreecommitdiff
path: root/drivers/uwb/scan.c
blob: 76a1a1ed7d3ec1e5831ca1d8024367e676cac266 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
/*
 * 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 <linux/slab.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);