These patches implement a feature essential for long distance wireless links:
setting ACK timeout and slot time. The API is based on a parameter called
Coverage Class specified by the 802.11 standard.
The first two patches add support to the kernel 802.11 stack via a new nl80211
attribute and a mac80211 callback.
Following three patches implement the callback in ath5k driver, after some
requisite fixes. Implementation in ath9k driver is planned.
Please note the last patch outside the series is not a kernel patch, it adds
the necessary support to userspace program iw.
This is a third version of these patches, with following minor changes:
* mac80211: add drv_ wrapper for mac80211 callback including tracer
* ath5k: move setting ah_coverage_class to ath5k_hw_set_coverage_class()
Lukas Turek
Mac80211 callback to driver set_coverage_class() sets slot time and ACK
timeout for given IEEE 802.11 coverage class. The callback is optional,
but it's essential for long distance links.
Signed-off-by: Lukas Turek <[email protected]>
---
include/net/mac80211.h | 5 +++++
net/mac80211/cfg.c | 7 +++++++
net/mac80211/driver-ops.h | 15 +++++++++++++++
net/mac80211/driver-trace.h | 23 +++++++++++++++++++++++
4 files changed, 50 insertions(+), 0 deletions(-)
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 538d6b7..669e57d 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1483,6 +1483,10 @@ enum ieee80211_ampdu_mlme_action {
* need to set wiphy->rfkill_poll to %true before registration,
* and need to call wiphy_rfkill_set_hw_state() in the callback.
*
+ * @set_coverage_class: Set slot time for given coverage class as specified
+ * in IEEE 802.11-2007 section 17.3.8.6 and modify ACK timeout
+ * accordingly. This callback is not required and may sleep.
+ *
* @testmode_cmd: Implement a cfg80211 test mode command.
*/
struct ieee80211_ops {
@@ -1537,6 +1541,7 @@ struct ieee80211_ops {
struct ieee80211_sta *sta, u16 tid, u16 *ssn);
void (*rfkill_poll)(struct ieee80211_hw *hw);
+ void (*set_coverage_class)(struct ieee80211_hw *hw, u8 coverage_class);
#ifdef CONFIG_NL80211_TESTMODE
int (*testmode_cmd)(struct ieee80211_hw *hw, void *data, int len);
#endif
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 6dc3579..d63819b 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1237,6 +1237,13 @@ static int ieee80211_set_wiphy_params(struct wiphy *wiphy, u32 changed)
struct ieee80211_local *local = wiphy_priv(wiphy);
int err;
+ if (changed & WIPHY_PARAM_COVERAGE_CLASS) {
+ err = drv_set_coverage_class(local, wiphy->coverage_class);
+
+ if (err)
+ return err;
+ }
+
if (changed & WIPHY_PARAM_RTS_THRESHOLD) {
err = drv_set_rts_threshold(local, wiphy->rts_threshold);
diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index 921dd9c..bba1e69 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -178,6 +178,21 @@ static inline int drv_set_rts_threshold(struct ieee80211_local *local,
return ret;
}
+static inline int drv_set_coverage_class(struct ieee80211_local *local,
+ u8 value)
+{
+ int ret = 0;
+ might_sleep();
+
+ if (local->ops->set_coverage_class)
+ local->ops->set_coverage_class(&local->hw, value);
+ else
+ ret = -EOPNOTSUPP;
+
+ trace_drv_set_coverage_class(local, value, ret);
+ return ret;
+}
+
static inline void drv_sta_notify(struct ieee80211_local *local,
struct ieee80211_vif *vif,
enum sta_notify_cmd cmd,
diff --git a/net/mac80211/driver-trace.h b/net/mac80211/driver-trace.h
index ee94ea0..1b770ae 100644
--- a/net/mac80211/driver-trace.h
+++ b/net/mac80211/driver-trace.h
@@ -489,6 +489,29 @@ TRACE_EVENT(drv_set_rts_threshold,
)
);
+TRACE_EVENT(drv_set_coverage_class,
+ TP_PROTO(struct ieee80211_local *local, u8 value, int ret),
+
+ TP_ARGS(local, value, ret),
+
+ TP_STRUCT__entry(
+ LOCAL_ENTRY
+ __field(u8, value)
+ __field(int, ret)
+ ),
+
+ TP_fast_assign(
+ LOCAL_ASSIGN;
+ __entry->ret = ret;
+ __entry->value = value;
+ ),
+
+ TP_printk(
+ LOCAL_PR_FMT " value:%d ret:%d",
+ LOCAL_PR_ARG, __entry->value, __entry->ret
+ )
+);
+
TRACE_EVENT(drv_sta_notify,
TP_PROTO(struct ieee80211_local *local,
struct ieee80211_vif *vif,
--
1.6.4.4
The new attribute NL80211_ATTR_WIPHY_COVERAGE_CLASS sets IEEE 802.11
Coverage Class, which depends on maximum distance of nodes in a
wireless network. It's required for long distance links (more than a few
hundred meters).
The attribute is now ignored by two non-mac80211 drivers, rndis and
iwmc3200wifi, together with WIPHY_PARAM_RETRY_SHORT and
WIPHY_PARAM_RETRY_LONG. If it turns out to be a problem, we could split
set_wiphy_params callback or add new capability bits.
Signed-off-by: Lukas Turek <[email protected]>
---
include/linux/nl80211.h | 4 ++++
include/net/cfg80211.h | 2 ++
net/wireless/core.c | 1 +
net/wireless/nl80211.c | 15 +++++++++++++++
4 files changed, 22 insertions(+), 0 deletions(-)
diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index da8ea2e..e241ed1 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -402,6 +402,8 @@ enum nl80211_commands {
* @NL80211_ATTR_WIPHY_RTS_THRESHOLD: RTS threshold (TX frames with length
* larger than or equal to this use RTS/CTS handshake); allowed range:
* 0..65536, disable with (u32)-1; dot11RTSThreshold; u32
+ * @NL80211_ATTR_WIPHY_COVERAGE_CLASS: Coverage Class as defined by IEEE 802.11
+ * section 7.3.2.9; dot11CoverageClass; u8
*
* @NL80211_ATTR_IFINDEX: network interface index of the device to operate on
* @NL80211_ATTR_IFNAME: network interface name
@@ -743,6 +745,8 @@ enum nl80211_attrs {
NL80211_ATTR_PMKID,
NL80211_ATTR_MAX_NUM_PMKIDS,
+ NL80211_ATTR_WIPHY_COVERAGE_CLASS,
+
/* add attributes here, update the policy in nl80211.c */
__NL80211_ATTR_AFTER_LAST,
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 0884b9a..fe50c71 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -837,6 +837,7 @@ enum wiphy_params_flags {
WIPHY_PARAM_RETRY_LONG = 1 << 1,
WIPHY_PARAM_FRAG_THRESHOLD = 1 << 2,
WIPHY_PARAM_RTS_THRESHOLD = 1 << 3,
+ WIPHY_PARAM_COVERAGE_CLASS = 1 << 4,
};
/**
@@ -1217,6 +1218,7 @@ struct wiphy {
u8 retry_long;
u32 frag_threshold;
u32 rts_threshold;
+ u8 coverage_class;
char fw_version[ETHTOOL_BUSINFO_LEN];
u32 hw_version;
diff --git a/net/wireless/core.c b/net/wireless/core.c
index c2a2c56..0a545bb 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -402,6 +402,7 @@ struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
rdev->wiphy.retry_long = 4;
rdev->wiphy.frag_threshold = (u32) -1;
rdev->wiphy.rts_threshold = (u32) -1;
+ rdev->wiphy.coverage_class = 0;
return &rdev->wiphy;
}
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 7cb0d64..ea86c28 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -69,6 +69,7 @@ static struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] __read_mostly = {
[NL80211_ATTR_WIPHY_RETRY_LONG] = { .type = NLA_U8 },
[NL80211_ATTR_WIPHY_FRAG_THRESHOLD] = { .type = NLA_U32 },
[NL80211_ATTR_WIPHY_RTS_THRESHOLD] = { .type = NLA_U32 },
+ [NL80211_ATTR_WIPHY_COVERAGE_CLASS] = { .type = NLA_U8 },
[NL80211_ATTR_IFTYPE] = { .type = NLA_U32 },
[NL80211_ATTR_IFINDEX] = { .type = NLA_U32 },
@@ -442,6 +443,8 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
dev->wiphy.frag_threshold);
NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_RTS_THRESHOLD,
dev->wiphy.rts_threshold);
+ NLA_PUT_U8(msg, NL80211_ATTR_WIPHY_COVERAGE_CLASS,
+ dev->wiphy.coverage_class);
NLA_PUT_U8(msg, NL80211_ATTR_MAX_NUM_SCAN_SSIDS,
dev->wiphy.max_scan_ssids);
@@ -681,6 +684,7 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
u32 changed;
u8 retry_short = 0, retry_long = 0;
u32 frag_threshold = 0, rts_threshold = 0;
+ u8 coverage_class = 0;
rtnl_lock();
@@ -803,9 +807,16 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
changed |= WIPHY_PARAM_RTS_THRESHOLD;
}
+ if (info->attrs[NL80211_ATTR_WIPHY_COVERAGE_CLASS]) {
+ coverage_class = nla_get_u8(
+ info->attrs[NL80211_ATTR_WIPHY_COVERAGE_CLASS]);
+ changed |= WIPHY_PARAM_COVERAGE_CLASS;
+ }
+
if (changed) {
u8 old_retry_short, old_retry_long;
u32 old_frag_threshold, old_rts_threshold;
+ u8 old_coverage_class;
if (!rdev->ops->set_wiphy_params) {
result = -EOPNOTSUPP;
@@ -816,6 +827,7 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
old_retry_long = rdev->wiphy.retry_long;
old_frag_threshold = rdev->wiphy.frag_threshold;
old_rts_threshold = rdev->wiphy.rts_threshold;
+ old_coverage_class = rdev->wiphy.coverage_class;
if (changed & WIPHY_PARAM_RETRY_SHORT)
rdev->wiphy.retry_short = retry_short;
@@ -825,6 +837,8 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
rdev->wiphy.frag_threshold = frag_threshold;
if (changed & WIPHY_PARAM_RTS_THRESHOLD)
rdev->wiphy.rts_threshold = rts_threshold;
+ if (changed & WIPHY_PARAM_COVERAGE_CLASS)
+ rdev->wiphy.coverage_class = coverage_class;
result = rdev->ops->set_wiphy_params(&rdev->wiphy, changed);
if (result) {
@@ -832,6 +846,7 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
rdev->wiphy.retry_long = old_retry_long;
rdev->wiphy.frag_threshold = old_frag_threshold;
rdev->wiphy.rts_threshold = old_rts_threshold;
+ rdev->wiphy.coverage_class = old_coverage_class;
}
}
--
1.6.4.4
New nl80211 attribute NL80211_ATTR_WIPHY_COVERAGE_CLASS allows setting
IEEE 802.11 coverage class, which is then used by drivers to calculate
slot time and ACK timeout for long distance links.
Two iw parameters are added: 'coverage' sets the coverage class
directly, while 'distance' is more user-friendly, as it allows to set
just the link distance and let iw do the necessary calculation itself.
Signed-off-by: Lukas Turek <[email protected]>
---
info.c | 8 ++++++++
nl80211.h | 15 +++++++++++++++
phy.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 81 insertions(+), 0 deletions(-)
diff --git a/info.c b/info.c
index 69af216..1a1b588 100644
--- a/info.c
+++ b/info.c
@@ -156,6 +156,14 @@ static int print_phy_handler(struct nl_msg *msg, void *arg)
printf("\tRTS threshold: %d\n", rts);
}
+ if (tb_msg[NL80211_ATTR_WIPHY_COVERAGE_CLASS]) {
+ unsigned char coverage;
+
+ coverage = nla_get_u8(tb_msg[NL80211_ATTR_WIPHY_COVERAGE_CLASS]);
+ /* See handle_distance() for an explanation where the '450' comes from */
+ printf("\tCoverage class: %d (up to %dm)\n", coverage, 450 * coverage);
+ }
+
if (!tb_msg[NL80211_ATTR_SUPPORTED_IFTYPES])
goto commands;
diff --git a/nl80211.h b/nl80211.h
index 45db17f..e241ed1 100644
--- a/nl80211.h
+++ b/nl80211.h
@@ -349,6 +349,10 @@ enum nl80211_commands {
NL80211_CMD_GET_SURVEY,
NL80211_CMD_NEW_SURVEY_RESULTS,
+ NL80211_CMD_SET_PMKSA,
+ NL80211_CMD_DEL_PMKSA,
+ NL80211_CMD_FLUSH_PMKSA,
+
/* add new commands above here */
/* used to define NL80211_CMD_MAX below */
@@ -398,6 +402,8 @@ enum nl80211_commands {
* @NL80211_ATTR_WIPHY_RTS_THRESHOLD: RTS threshold (TX frames with length
* larger than or equal to this use RTS/CTS handshake); allowed range:
* 0..65536, disable with (u32)-1; dot11RTSThreshold; u32
+ * @NL80211_ATTR_WIPHY_COVERAGE_CLASS: Coverage Class as defined by IEEE 802.11
+ * section 7.3.2.9; dot11CoverageClass; u8
*
* @NL80211_ATTR_IFINDEX: network interface index of the device to operate on
* @NL80211_ATTR_IFNAME: network interface name
@@ -598,6 +604,10 @@ enum nl80211_commands {
* the survey response for %NL80211_CMD_GET_SURVEY, nested attribute
* containing info as possible, see &enum survey_info.
*
+ * @NL80211_ATTR_PMKID: PMK material for PMKSA caching.
+ * @NL80211_ATTR_MAX_NUM_PMKIDS: maximum number of PMKIDs a firmware can
+ * cache, a wiphy attribute.
+ *
* @NL80211_ATTR_MAX: highest attribute number currently defined
* @__NL80211_ATTR_AFTER_LAST: internal use
*/
@@ -732,6 +742,11 @@ enum nl80211_attrs {
NL80211_ATTR_SURVEY_INFO,
+ NL80211_ATTR_PMKID,
+ NL80211_ATTR_MAX_NUM_PMKIDS,
+
+ NL80211_ATTR_WIPHY_COVERAGE_CLASS,
+
/* add attributes here, update the policy in nl80211.c */
__NL80211_ATTR_AFTER_LAST,
diff --git a/phy.c b/phy.c
index 8dd01aa..1de58a9 100644
--- a/phy.c
+++ b/phy.c
@@ -164,3 +164,61 @@ static int handle_netns(struct nl80211_state *state,
COMMAND(set, netns, "<pid>",
NL80211_CMD_SET_WIPHY_NETNS, 0, CIB_PHY, handle_netns,
"Put this wireless device into a different network namespace");
+
+static int handle_coverage(struct nl80211_state *state,
+ struct nl_cb *cb,
+ struct nl_msg *msg,
+ int argc, char **argv)
+{
+ unsigned int coverage;
+
+ if (argc != 1)
+ return 1;
+
+ coverage = strtoul(argv[0], NULL, 10);
+ if (coverage > 255)
+ return 1;
+
+ NLA_PUT_U8(msg, NL80211_ATTR_WIPHY_COVERAGE_CLASS, coverage);
+
+ return 0;
+ nla_put_failure:
+ return -ENOBUFS;
+}
+COMMAND(set, coverage, "<coverage class>",
+ NL80211_CMD_SET_WIPHY, 0, CIB_PHY, handle_coverage,
+ "Set coverage class (1 for every 3 usec of air propagation time).\n"
+ "Valid values: 0 - 255.");
+
+static int handle_distance(struct nl80211_state *state,
+ struct nl_cb *cb,
+ struct nl_msg *msg,
+ int argc, char **argv)
+{
+ unsigned int distance, coverage;
+
+ if (argc != 1)
+ return 1;
+
+ distance = strtoul(argv[0], NULL, 10);
+
+ /*
+ * Divide double the distance by the speed of light in m/usec (300) to
+ * get round-trip time in microseconds and then divide the result by
+ * three to get coverage class as specified in IEEE 802.11-2007 table
+ * 7-27. Values are rounded upwards.
+ */
+ coverage = (distance + 449) / 450;
+ if (coverage > 255)
+ return 1;
+
+ NLA_PUT_U8(msg, NL80211_ATTR_WIPHY_COVERAGE_CLASS, coverage);
+
+ return 0;
+ nla_put_failure:
+ return -ENOBUFS;
+}
+COMMAND(set, distance, "<distance>",
+ NL80211_CMD_SET_WIPHY, 0, CIB_PHY, handle_distance,
+ "Set appropriate coverage class for given link distance in meters.\n"
+ "Valid values: 0 - 114750");
--
1.6.4.4
The callback sets slot time as specified in IEEE 802.11-2007 section
17.3.8.6 (for 20MHz channels only for now) and raises ACK and CTS
timeouts accordingly. The values are persistent, they are restored after
device reset.
Signed-off-by: Lukas Turek <[email protected]>
---
drivers/net/wireless/ath/ath5k/ath5k.h | 2 +
drivers/net/wireless/ath/ath5k/base.c | 22 ++++++++++++
drivers/net/wireless/ath/ath5k/pcu.c | 57 ++++++++++++++++++++++++++++++++
drivers/net/wireless/ath/ath5k/reset.c | 4 ++
4 files changed, 85 insertions(+), 0 deletions(-)
diff --git a/drivers/net/wireless/ath/ath5k/ath5k.h b/drivers/net/wireless/ath/ath5k/ath5k.h
index ae311d2..66bcb50 100644
--- a/drivers/net/wireless/ath/ath5k/ath5k.h
+++ b/drivers/net/wireless/ath/ath5k/ath5k.h
@@ -1063,6 +1063,7 @@ struct ath5k_hw {
u32 ah_cw_min;
u32 ah_cw_max;
u32 ah_limit_tx_retries;
+ u8 ah_coverage_class;
/* Antenna Control */
u32 ah_ant_ctl[AR5K_EEPROM_N_MODES][AR5K_ANT_MAX];
@@ -1200,6 +1201,7 @@ extern bool ath5k_eeprom_is_hb63(struct ath5k_hw *ah);
/* Protocol Control Unit Functions */
extern int ath5k_hw_set_opmode(struct ath5k_hw *ah);
+extern void ath5k_hw_set_coverage_class(struct ath5k_hw *ah, u8 coverage_class);
/* BSSID Functions */
extern int ath5k_hw_set_lladdr(struct ath5k_hw *ah, const u8 *mac);
extern void ath5k_hw_set_associd(struct ath5k_hw *ah);
diff --git a/drivers/net/wireless/ath/ath5k/base.c b/drivers/net/wireless/ath/ath5k/base.c
index a4c086f..2826cbc 100644
--- a/drivers/net/wireless/ath/ath5k/base.c
+++ b/drivers/net/wireless/ath/ath5k/base.c
@@ -254,6 +254,8 @@ static void ath5k_bss_info_changed(struct ieee80211_hw *hw,
u32 changes);
static void ath5k_sw_scan_start(struct ieee80211_hw *hw);
static void ath5k_sw_scan_complete(struct ieee80211_hw *hw);
+static void ath5k_set_coverage_class(struct ieee80211_hw *hw,
+ u8 coverage_class);
static const struct ieee80211_ops ath5k_hw_ops = {
.tx = ath5k_tx,
@@ -274,6 +276,7 @@ static const struct ieee80211_ops ath5k_hw_ops = {
.bss_info_changed = ath5k_bss_info_changed,
.sw_scan_start = ath5k_sw_scan_start,
.sw_scan_complete = ath5k_sw_scan_complete,
+ .set_coverage_class = ath5k_set_coverage_class,
};
/*
@@ -3274,3 +3277,22 @@ static void ath5k_sw_scan_complete(struct ieee80211_hw *hw)
ath5k_hw_set_ledstate(sc->ah, sc->assoc ?
AR5K_LED_ASSOC : AR5K_LED_INIT);
}
+
+/**
+ * ath5k_set_coverage_class - Set IEEE 802.11 coverage class
+ *
+ * @hw: struct ieee80211_hw pointer
+ * @coverage_class: IEEE 802.11 coverage class number
+ *
+ * Mac80211 callback. Sets slot time, ACK timeout and CTS timeout for given
+ * coverage class. The values are persistent, they are restored after device
+ * reset.
+ */
+static void ath5k_set_coverage_class(struct ieee80211_hw *hw, u8 coverage_class)
+{
+ struct ath5k_softc *sc = hw->priv;
+
+ mutex_lock(&sc->lock);
+ ath5k_hw_set_coverage_class(sc->ah, coverage_class);
+ mutex_unlock(&sc->lock);
+}
diff --git a/drivers/net/wireless/ath/ath5k/pcu.c b/drivers/net/wireless/ath/ath5k/pcu.c
index b601ff9..aefe84f 100644
--- a/drivers/net/wireless/ath/ath5k/pcu.c
+++ b/drivers/net/wireless/ath/ath5k/pcu.c
@@ -286,6 +286,42 @@ unsigned int ath5k_hw_get_clockrate(struct ath5k_hw *ah)
}
/**
+ * ath5k_hw_get_default_slottime - Get the default slot time for current mode
+ *
+ * @ah: The &struct ath5k_hw
+ */
+unsigned int ath5k_hw_get_default_slottime(struct ath5k_hw *ah)
+{
+ struct ieee80211_channel *channel = ah->ah_current_channel;
+
+ if (channel->hw_value & CHANNEL_TURBO)
+ return 6; /* both turbo modes */
+
+ if (channel->hw_value & CHANNEL_CCK)
+ return 20; /* 802.11b */
+
+ return 9; /* 802.11 a/g */
+}
+
+/**
+ * ath5k_hw_get_default_sifs - Get the default SIFS for current mode
+ *
+ * @ah: The &struct ath5k_hw
+ */
+unsigned int ath5k_hw_get_default_sifs(struct ath5k_hw *ah)
+{
+ struct ieee80211_channel *channel = ah->ah_current_channel;
+
+ if (channel->hw_value & CHANNEL_TURBO)
+ return 8; /* both turbo modes */
+
+ if (channel->hw_value & CHANNEL_5GHZ)
+ return 16; /* 802.11a */
+
+ return 10; /* 802.11 b/g */
+}
+
+/**
* ath5k_hw_set_lladdr - Set station id
*
* @ah: The &struct ath5k_hw
@@ -1094,3 +1130,24 @@ int ath5k_hw_set_key_lladdr(struct ath5k_hw *ah, u16 entry, const u8 *mac)
return 0;
}
+/**
+ * ath5k_hw_set_coverage_class - Set IEEE 802.11 coverage class
+ *
+ * @ah: The &struct ath5k_hw
+ * @coverage_class: IEEE 802.11 coverage class number
+ *
+ * Sets slot time, ACK timeout and CTS timeout for given coverage class.
+ */
+void ath5k_hw_set_coverage_class(struct ath5k_hw *ah, u8 coverage_class)
+{
+ /* As defined by IEEE 802.11-2007 17.3.8.6 */
+ int slot_time = ath5k_hw_get_default_slottime(ah) + 3 * coverage_class;
+ int ack_timeout = ath5k_hw_get_default_sifs(ah) + slot_time;
+ int cts_timeout = ack_timeout;
+
+ ath5k_hw_set_slot_time(ah, slot_time);
+ ath5k_hw_set_ack_timeout(ah, ack_timeout);
+ ath5k_hw_set_cts_timeout(ah, cts_timeout);
+
+ ah->ah_coverage_class = coverage_class;
+}
diff --git a/drivers/net/wireless/ath/ath5k/reset.c b/drivers/net/wireless/ath/ath5k/reset.c
index 299b33a..6690923 100644
--- a/drivers/net/wireless/ath/ath5k/reset.c
+++ b/drivers/net/wireless/ath/ath5k/reset.c
@@ -1316,6 +1316,10 @@ int ath5k_hw_reset(struct ath5k_hw *ah, enum nl80211_iftype op_mode,
/* Restore antenna mode */
ath5k_hw_set_antenna_mode(ah, ah->ah_ant_mode);
+ /* Restore slot time and ACK timeouts */
+ if (ah->ah_coverage_class > 0)
+ ath5k_hw_set_coverage_class(ah, ah->ah_coverage_class);
+
/*
* Configure QCUs/DCUs
*/
--
1.6.4.4
The original code was correct in 802.11a mode only, 802.11b/g uses
different clock rates. The new code uses values taken from FreeBSD HAL
and should be correct for all modes including turbo modes.
The former rate calculation was used by slope coefficient calculation
function ath5k_hw_write_ofdm_timings. However, this function requires
the 802.11a values even in 802.11g mode. Thus the use of
ath5k_hw_htoclock was replaced by hardcoded values. Possibly the slope
coefficient calculation is not related to clock rate at all.
Signed-off-by: Lukas Turek <[email protected]>
---
drivers/net/wireless/ath/ath5k/ath5k.h | 22 ++---------
drivers/net/wireless/ath/ath5k/pcu.c | 64 +++++++++++++++++++++++++++-----
drivers/net/wireless/ath/ath5k/qcu.c | 4 +-
drivers/net/wireless/ath/ath5k/reset.c | 5 +-
4 files changed, 62 insertions(+), 33 deletions(-)
diff --git a/drivers/net/wireless/ath/ath5k/ath5k.h b/drivers/net/wireless/ath/ath5k/ath5k.h
index 6a2a967..ae311d2 100644
--- a/drivers/net/wireless/ath/ath5k/ath5k.h
+++ b/drivers/net/wireless/ath/ath5k/ath5k.h
@@ -1231,6 +1231,10 @@ extern int ath5k_hw_set_ack_timeout(struct ath5k_hw *ah, unsigned int timeout);
extern unsigned int ath5k_hw_get_ack_timeout(struct ath5k_hw *ah);
extern int ath5k_hw_set_cts_timeout(struct ath5k_hw *ah, unsigned int timeout);
extern unsigned int ath5k_hw_get_cts_timeout(struct ath5k_hw *ah);
+/* Clock rate related functions */
+unsigned int ath5k_hw_htoclock(struct ath5k_hw *ah, unsigned int usec);
+unsigned int ath5k_hw_clocktoh(struct ath5k_hw *ah, unsigned int clock);
+unsigned int ath5k_hw_get_clockrate(struct ath5k_hw *ah);
/* Key table (WEP) functions */
extern int ath5k_hw_reset_key(struct ath5k_hw *ah, u16 entry);
extern int ath5k_hw_is_key_valid(struct ath5k_hw *ah, u16 entry);
@@ -1310,24 +1314,6 @@ extern int ath5k_hw_set_txpower_limit(struct ath5k_hw *ah, u8 txpower);
* Functions used internaly
*/
-/*
- * Translate usec to hw clock units
- * TODO: Half/quarter rate
- */
-static inline unsigned int ath5k_hw_htoclock(unsigned int usec, bool turbo)
-{
- return turbo ? (usec * 80) : (usec * 40);
-}
-
-/*
- * Translate hw clock units to usec
- * TODO: Half/quarter rate
- */
-static inline unsigned int ath5k_hw_clocktoh(unsigned int clock, bool turbo)
-{
- return turbo ? (clock / 80) : (clock / 40);
-}
-
static inline struct ath_common *ath5k_hw_common(struct ath5k_hw *ah)
{
return &ah->common;
diff --git a/drivers/net/wireless/ath/ath5k/pcu.c b/drivers/net/wireless/ath/ath5k/pcu.c
index 64fc1eb..b601ff9 100644
--- a/drivers/net/wireless/ath/ath5k/pcu.c
+++ b/drivers/net/wireless/ath/ath5k/pcu.c
@@ -187,8 +187,8 @@ unsigned int ath5k_hw_get_ack_timeout(struct ath5k_hw *ah)
{
ATH5K_TRACE(ah->ah_sc);
- return ath5k_hw_clocktoh(AR5K_REG_MS(ath5k_hw_reg_read(ah,
- AR5K_TIME_OUT), AR5K_TIME_OUT_ACK), ah->ah_turbo);
+ return ath5k_hw_clocktoh(ah, AR5K_REG_MS(ath5k_hw_reg_read(ah,
+ AR5K_TIME_OUT), AR5K_TIME_OUT_ACK));
}
/**
@@ -200,12 +200,12 @@ unsigned int ath5k_hw_get_ack_timeout(struct ath5k_hw *ah)
int ath5k_hw_set_ack_timeout(struct ath5k_hw *ah, unsigned int timeout)
{
ATH5K_TRACE(ah->ah_sc);
- if (ath5k_hw_clocktoh(AR5K_REG_MS(0xffffffff, AR5K_TIME_OUT_ACK),
- ah->ah_turbo) <= timeout)
+ if (ath5k_hw_clocktoh(ah, AR5K_REG_MS(0xffffffff, AR5K_TIME_OUT_ACK))
+ <= timeout)
return -EINVAL;
AR5K_REG_WRITE_BITS(ah, AR5K_TIME_OUT, AR5K_TIME_OUT_ACK,
- ath5k_hw_htoclock(timeout, ah->ah_turbo));
+ ath5k_hw_htoclock(ah, timeout));
return 0;
}
@@ -218,8 +218,8 @@ int ath5k_hw_set_ack_timeout(struct ath5k_hw *ah, unsigned int timeout)
unsigned int ath5k_hw_get_cts_timeout(struct ath5k_hw *ah)
{
ATH5K_TRACE(ah->ah_sc);
- return ath5k_hw_clocktoh(AR5K_REG_MS(ath5k_hw_reg_read(ah,
- AR5K_TIME_OUT), AR5K_TIME_OUT_CTS), ah->ah_turbo);
+ return ath5k_hw_clocktoh(ah, AR5K_REG_MS(ath5k_hw_reg_read(ah,
+ AR5K_TIME_OUT), AR5K_TIME_OUT_CTS));
}
/**
@@ -231,17 +231,61 @@ unsigned int ath5k_hw_get_cts_timeout(struct ath5k_hw *ah)
int ath5k_hw_set_cts_timeout(struct ath5k_hw *ah, unsigned int timeout)
{
ATH5K_TRACE(ah->ah_sc);
- if (ath5k_hw_clocktoh(AR5K_REG_MS(0xffffffff, AR5K_TIME_OUT_CTS),
- ah->ah_turbo) <= timeout)
+ if (ath5k_hw_clocktoh(ah, AR5K_REG_MS(0xffffffff, AR5K_TIME_OUT_CTS))
+ <= timeout)
return -EINVAL;
AR5K_REG_WRITE_BITS(ah, AR5K_TIME_OUT, AR5K_TIME_OUT_CTS,
- ath5k_hw_htoclock(timeout, ah->ah_turbo));
+ ath5k_hw_htoclock(ah, timeout));
return 0;
}
/**
+ * ath5k_hw_htoclock - Translate usec to hw clock units
+ *
+ * @ah: The &struct ath5k_hw
+ * @usec: value in microseconds
+ */
+unsigned int ath5k_hw_htoclock(struct ath5k_hw *ah, unsigned int usec)
+{
+ return usec * ath5k_hw_get_clockrate(ah);
+}
+
+/**
+ * ath5k_hw_clocktoh - Translate hw clock units to usec
+ * @clock: value in hw clock units
+ */
+unsigned int ath5k_hw_clocktoh(struct ath5k_hw *ah, unsigned int clock)
+{
+ return clock / ath5k_hw_get_clockrate(ah);
+}
+
+/**
+ * ath5k_hw_get_clockrate - Get the clock rate for current mode
+ *
+ * @ah: The &struct ath5k_hw
+ */
+unsigned int ath5k_hw_get_clockrate(struct ath5k_hw *ah)
+{
+ struct ieee80211_channel *channel = ah->ah_current_channel;
+ int clock;
+
+ if (channel->hw_value & CHANNEL_5GHZ)
+ clock = 40; /* 802.11a */
+ else if (channel->hw_value & CHANNEL_CCK)
+ clock = 22; /* 802.11b */
+ else
+ clock = 44; /* 802.11g */
+
+ /* Clock rate in turbo modes is twice the normal rate */
+ if (channel->hw_value & CHANNEL_TURBO)
+ clock *= 2;
+
+ return clock;
+}
+
+/**
* ath5k_hw_set_lladdr - Set station id
*
* @ah: The &struct ath5k_hw
diff --git a/drivers/net/wireless/ath/ath5k/qcu.c b/drivers/net/wireless/ath/ath5k/qcu.c
index e322a10..abe36c0 100644
--- a/drivers/net/wireless/ath/ath5k/qcu.c
+++ b/drivers/net/wireless/ath/ath5k/qcu.c
@@ -529,7 +529,7 @@ unsigned int ath5k_hw_get_slot_time(struct ath5k_hw *ah)
else
slot_time_clock = ath5k_hw_reg_read(ah, AR5K_DCU_GBL_IFS_SLOT);
- return ath5k_hw_clocktoh(slot_time_clock & 0xffff, ah->ah_turbo);
+ return ath5k_hw_clocktoh(ah, slot_time_clock & 0xffff);
}
/*
@@ -537,7 +537,7 @@ unsigned int ath5k_hw_get_slot_time(struct ath5k_hw *ah)
*/
int ath5k_hw_set_slot_time(struct ath5k_hw *ah, unsigned int slot_time)
{
- u32 slot_time_clock = ath5k_hw_htoclock(slot_time, ah->ah_turbo);
+ u32 slot_time_clock = ath5k_hw_htoclock(ah, slot_time);
ATH5K_TRACE(ah->ah_sc);
diff --git a/drivers/net/wireless/ath/ath5k/reset.c b/drivers/net/wireless/ath/ath5k/reset.c
index 62954fc..299b33a 100644
--- a/drivers/net/wireless/ath/ath5k/reset.c
+++ b/drivers/net/wireless/ath/ath5k/reset.c
@@ -60,12 +60,11 @@ static inline int ath5k_hw_write_ofdm_timings(struct ath5k_hw *ah,
!(channel->hw_value & CHANNEL_OFDM));
/* Get coefficient
- * ALGO: coef = (5 * clock * carrier_freq) / 2)
+ * ALGO: coef = (5 * clock / carrier_freq) / 2
* we scale coef by shifting clock value by 24 for
* better precision since we use integers */
/* TODO: Half/quarter rate */
- clock = ath5k_hw_htoclock(1, channel->hw_value & CHANNEL_TURBO);
-
+ clock = (channel->hw_value & CHANNEL_TURBO) ? 80 : 40;
coef_scaled = ((5 * (clock << 24)) / 2) / channel->center_freq;
/* Get exponent
--
1.6.4.4
Functions ath5k_hw_get_slot_time and ath5k_hw_set_slot_time were
converting microseconds to clocks only for AR5210, although it's needed
for all supported devices. The conversion was moved outside the
hardware-specific branches.
The original code also limited minimum slot time to 9, while turbo modes
use 6, this was fixed too.
Signed-off-by: Lukas Turek <[email protected]>
---
drivers/net/wireless/ath/ath5k/qcu.c | 20 +++++++++++++-------
1 files changed, 13 insertions(+), 7 deletions(-)
diff --git a/drivers/net/wireless/ath/ath5k/qcu.c b/drivers/net/wireless/ath/ath5k/qcu.c
index eeebb9a..e322a10 100644
--- a/drivers/net/wireless/ath/ath5k/qcu.c
+++ b/drivers/net/wireless/ath/ath5k/qcu.c
@@ -520,12 +520,16 @@ int ath5k_hw_reset_tx_queue(struct ath5k_hw *ah, unsigned int queue)
*/
unsigned int ath5k_hw_get_slot_time(struct ath5k_hw *ah)
{
+ unsigned int slot_time_clock;
+
ATH5K_TRACE(ah->ah_sc);
+
if (ah->ah_version == AR5K_AR5210)
- return ath5k_hw_clocktoh(ath5k_hw_reg_read(ah,
- AR5K_SLOT_TIME) & 0xffff, ah->ah_turbo);
+ slot_time_clock = ath5k_hw_reg_read(ah, AR5K_SLOT_TIME);
else
- return ath5k_hw_reg_read(ah, AR5K_DCU_GBL_IFS_SLOT) & 0xffff;
+ slot_time_clock = ath5k_hw_reg_read(ah, AR5K_DCU_GBL_IFS_SLOT);
+
+ return ath5k_hw_clocktoh(slot_time_clock & 0xffff, ah->ah_turbo);
}
/*
@@ -533,15 +537,17 @@ unsigned int ath5k_hw_get_slot_time(struct ath5k_hw *ah)
*/
int ath5k_hw_set_slot_time(struct ath5k_hw *ah, unsigned int slot_time)
{
+ u32 slot_time_clock = ath5k_hw_htoclock(slot_time, ah->ah_turbo);
+
ATH5K_TRACE(ah->ah_sc);
- if (slot_time < AR5K_SLOT_TIME_9 || slot_time > AR5K_SLOT_TIME_MAX)
+
+ if (slot_time < 6 || slot_time_clock > AR5K_SLOT_TIME_MAX)
return -EINVAL;
if (ah->ah_version == AR5K_AR5210)
- ath5k_hw_reg_write(ah, ath5k_hw_htoclock(slot_time,
- ah->ah_turbo), AR5K_SLOT_TIME);
+ ath5k_hw_reg_write(ah, slot_time_clock, AR5K_SLOT_TIME);
else
- ath5k_hw_reg_write(ah, slot_time, AR5K_DCU_GBL_IFS_SLOT);
+ ath5k_hw_reg_write(ah, slot_time_clock, AR5K_DCU_GBL_IFS_SLOT);
return 0;
}
--
1.6.4.4
On Mon, Dec 21, 2009 at 1:50 PM, Lukáš Turek <[email protected]> wrote:
> New nl80211 attribute NL80211_ATTR_WIPHY_COVERAGE_CLASS allows setting
> IEEE 802.11 coverage class, which is then used by drivers to calculate
> slot time and ACK timeout for long distance links.
>
> Two iw parameters are added: 'coverage' sets the coverage class
> directly, while 'distance' is more user-friendly, as it allows to set
> just the link distance and let iw do the necessary calculation itself.
>
> Signed-off-by: Lukas Turek <[email protected]>
This wasn't applied so going to resend rebasing with latest nl80211.h.
Luis