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linux/drivers/net/wireless/libertas/cfg.c
Johannes Berg f444de05d2 cfg80211/mac80211: better channel handling
Currently (all tested with hwsim) you can do stupid
things like setting up an AP on a certain channel,
then adding another virtual interface and making
that associate on another channel -- this will make
the beaconing to move channel but obviously without
the necessary IEs data update.

In order to improve this situation, first make the
configuration APIs (cfg80211 and nl80211) aware of
multi-channel operation -- we'll eventually need
that in the future anyway. There's one userland API
change and one API addition. The API change is that
now SET_WIPHY must be called with virtual interface
index rather than only wiphy index in order to take
effect for that interface -- luckily all current
users (hostapd) do that. For monitor interfaces, the
old setting is preserved, but monitors are always
slaved to other devices anyway so no guarantees.

The second userland API change is the introduction
of a per virtual interface SET_CHANNEL command, that
hostapd should use going forward to make it easier
to understand what's going on (it can automatically
detect a kernel with this command).

Other than mac80211, no existing cfg80211 drivers
are affected by this change because they only allow
a single virtual interface.

mac80211, however, now needs to be aware that the
channel settings are per interface now, and needs
to disallow (for now) real multi-channel operation,
which is another important part of this patch.

One of the immediate benefits is that you can now
start hostapd to operate on a hardware that already
has a connection on another virtual interface, as
long as you specify the same channel.

Note that two things are left unhandled (this is an
improvement -- not a complete fix):

 * different HT/no-HT modes

   currently you could start an HT AP and then
   connect to a non-HT network on the same channel
   which would configure the hardware for no HT;
   that can be fixed fairly easily

 * CSA

   An AP we're connected to on a virtual interface
   might indicate switching channels, and in that
   case we would follow it, regardless of how many
   other interfaces are operating; this requires
   more effort to fix but is pretty rare after all

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-05-07 14:55:50 -04:00

204 lines
4.6 KiB
C

/*
* Implement cfg80211 ("iw") support.
*
* Copyright (C) 2009 M&N Solutions GmbH, 61191 Rosbach, Germany
* Holger Schurig <hs4233@mail.mn-solutions.de>
*
*/
#include <net/cfg80211.h>
#include "cfg.h"
#include "cmd.h"
#define CHAN2G(_channel, _freq, _flags) { \
.band = IEEE80211_BAND_2GHZ, \
.center_freq = (_freq), \
.hw_value = (_channel), \
.flags = (_flags), \
.max_antenna_gain = 0, \
.max_power = 30, \
}
static struct ieee80211_channel lbs_2ghz_channels[] = {
CHAN2G(1, 2412, 0),
CHAN2G(2, 2417, 0),
CHAN2G(3, 2422, 0),
CHAN2G(4, 2427, 0),
CHAN2G(5, 2432, 0),
CHAN2G(6, 2437, 0),
CHAN2G(7, 2442, 0),
CHAN2G(8, 2447, 0),
CHAN2G(9, 2452, 0),
CHAN2G(10, 2457, 0),
CHAN2G(11, 2462, 0),
CHAN2G(12, 2467, 0),
CHAN2G(13, 2472, 0),
CHAN2G(14, 2484, 0),
};
#define RATETAB_ENT(_rate, _rateid, _flags) { \
.bitrate = (_rate), \
.hw_value = (_rateid), \
.flags = (_flags), \
}
static struct ieee80211_rate lbs_rates[] = {
RATETAB_ENT(10, 0x1, 0),
RATETAB_ENT(20, 0x2, 0),
RATETAB_ENT(55, 0x4, 0),
RATETAB_ENT(110, 0x8, 0),
RATETAB_ENT(60, 0x10, 0),
RATETAB_ENT(90, 0x20, 0),
RATETAB_ENT(120, 0x40, 0),
RATETAB_ENT(180, 0x80, 0),
RATETAB_ENT(240, 0x100, 0),
RATETAB_ENT(360, 0x200, 0),
RATETAB_ENT(480, 0x400, 0),
RATETAB_ENT(540, 0x800, 0),
};
static struct ieee80211_supported_band lbs_band_2ghz = {
.channels = lbs_2ghz_channels,
.n_channels = ARRAY_SIZE(lbs_2ghz_channels),
.bitrates = lbs_rates,
.n_bitrates = ARRAY_SIZE(lbs_rates),
};
static const u32 cipher_suites[] = {
WLAN_CIPHER_SUITE_WEP40,
WLAN_CIPHER_SUITE_WEP104,
WLAN_CIPHER_SUITE_TKIP,
WLAN_CIPHER_SUITE_CCMP,
};
static int lbs_cfg_set_channel(struct wiphy *wiphy,
struct net_device *netdev,
struct ieee80211_channel *chan,
enum nl80211_channel_type channel_type)
{
struct lbs_private *priv = wiphy_priv(wiphy);
int ret = -ENOTSUPP;
lbs_deb_enter_args(LBS_DEB_CFG80211, "freq %d, type %d", chan->center_freq, channel_type);
if (channel_type != NL80211_CHAN_NO_HT)
goto out;
ret = lbs_set_channel(priv, chan->hw_value);
out:
lbs_deb_leave_args(LBS_DEB_CFG80211, "ret %d", ret);
return ret;
}
static struct cfg80211_ops lbs_cfg80211_ops = {
.set_channel = lbs_cfg_set_channel,
};
/*
* At this time lbs_private *priv doesn't even exist, so we just allocate
* memory and don't initialize the wiphy further. This is postponed until we
* can talk to the firmware and happens at registration time in
* lbs_cfg_wiphy_register().
*/
struct wireless_dev *lbs_cfg_alloc(struct device *dev)
{
int ret = 0;
struct wireless_dev *wdev;
lbs_deb_enter(LBS_DEB_CFG80211);
wdev = kzalloc(sizeof(struct wireless_dev), GFP_KERNEL);
if (!wdev) {
dev_err(dev, "cannot allocate wireless device\n");
return ERR_PTR(-ENOMEM);
}
wdev->wiphy = wiphy_new(&lbs_cfg80211_ops, sizeof(struct lbs_private));
if (!wdev->wiphy) {
dev_err(dev, "cannot allocate wiphy\n");
ret = -ENOMEM;
goto err_wiphy_new;
}
lbs_deb_leave(LBS_DEB_CFG80211);
return wdev;
err_wiphy_new:
kfree(wdev);
lbs_deb_leave_args(LBS_DEB_CFG80211, "ret %d", ret);
return ERR_PTR(ret);
}
/*
* This function get's called after lbs_setup_firmware() determined the
* firmware capabities. So we can setup the wiphy according to our
* hardware/firmware.
*/
int lbs_cfg_register(struct lbs_private *priv)
{
struct wireless_dev *wdev = priv->wdev;
int ret;
lbs_deb_enter(LBS_DEB_CFG80211);
wdev->wiphy->max_scan_ssids = 1;
wdev->wiphy->signal_type = CFG80211_SIGNAL_TYPE_MBM;
/* TODO: BIT(NL80211_IFTYPE_ADHOC); */
wdev->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
/* TODO: honor priv->regioncode */
wdev->wiphy->bands[IEEE80211_BAND_2GHZ] = &lbs_band_2ghz;
/*
* We could check priv->fwcapinfo && FW_CAPINFO_WPA, but I have
* never seen a firmware without WPA
*/
wdev->wiphy->cipher_suites = cipher_suites;
wdev->wiphy->n_cipher_suites = ARRAY_SIZE(cipher_suites);
ret = wiphy_register(wdev->wiphy);
if (ret < 0)
lbs_pr_err("cannot register wiphy device\n");
priv->wiphy_registered = true;
ret = register_netdev(priv->dev);
if (ret)
lbs_pr_err("cannot register network device\n");
lbs_deb_leave_args(LBS_DEB_CFG80211, "ret %d", ret);
return ret;
}
void lbs_cfg_free(struct lbs_private *priv)
{
struct wireless_dev *wdev = priv->wdev;
lbs_deb_enter(LBS_DEB_CFG80211);
if (!wdev)
return;
if (priv->wiphy_registered)
wiphy_unregister(wdev->wiphy);
if (wdev->wiphy)
wiphy_free(wdev->wiphy);
kfree(wdev);
}