diff options
| -rw-r--r-- | drivers/net/wireless/rt2x00/rt2x00.h | 87 | ||||
| -rw-r--r-- | drivers/net/wireless/rt2x00/rt2x00config.c | 26 | ||||
| -rw-r--r-- | drivers/net/wireless/rt2x00/rt2x00dev.c | 138 | ||||
| -rw-r--r-- | drivers/net/wireless/rt2x00/rt2x00lib.h | 2 |
4 files changed, 232 insertions, 21 deletions
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h index d6f0a72b7a0..e7533e2ccd2 100644 --- a/drivers/net/wireless/rt2x00/rt2x00.h +++ b/drivers/net/wireless/rt2x00/rt2x00.h @@ -241,6 +241,43 @@ struct link_qual { }; /* + * Antenna settings about the currently active link. + */ +struct link_ant { + /* + * Antenna flags + */ + unsigned int flags; +#define ANTENNA_RX_DIVERSITY 0x00000001 +#define ANTENNA_TX_DIVERSITY 0x00000002 +#define ANTENNA_MODE_SAMPLE 0x00000004 + + /* + * Currently active TX/RX antenna setup. + * When software diversity is used, this will indicate + * which antenna is actually used at this time. + */ + struct antenna_setup active; + + /* + * RSSI information for the different antenna's. + * These statistics are used to determine when + * to switch antenna when using software diversity. + * + * rssi[0] -> Antenna A RSSI + * rssi[1] -> Antenna B RSSI + */ + int rssi_history[2]; + + /* + * Current RSSI average of the currently active antenna. + * Similar to the avg_rssi in the link_qual structure + * this value is updated by using the walking average. + */ + int rssi_ant; +}; + +/* * To optimize the quality of the link we need to store * the quality of received frames and periodically * optimize the link. @@ -259,11 +296,9 @@ struct link { struct link_qual qual; /* - * Currently active TX/RX antenna setup. - * When software diversity is used, this will indicate - * which antenna is actually used at this time. + * TX/RX antenna setup. */ - struct antenna_setup active_ant; + struct link_ant ant; /* * Active VGC level @@ -277,25 +312,47 @@ struct link { }; /* - * Update the rssi using the walking average approach. + * Small helper macro to work with moving/walking averages. */ -static inline void rt2x00_update_link_rssi(struct link *link, int rssi) -{ - if (link->qual.avg_rssi) - rssi = ((link->qual.avg_rssi * 7) + rssi) / 8; - link->qual.avg_rssi = rssi; -} +#define MOVING_AVERAGE(__avg, __val, __samples) \ + ( (((__avg) * ((__samples) - 1)) + (__val)) / (__samples) ) + +/* + * When we lack RSSI information return something less then -80 to + * tell the driver to tune the device to maximum sensitivity. + */ +#define DEFAULT_RSSI ( -128 ) /* - * When the avg_rssi is unset or no frames have been received), - * we need to return the default value which needs to be less - * than -80 so the device will select the maximum sensitivity. + * Link quality access functions. */ static inline int rt2x00_get_link_rssi(struct link *link) { if (link->qual.avg_rssi && link->qual.rx_success) return link->qual.avg_rssi; - return -128; + return DEFAULT_RSSI; +} + +static inline int rt2x00_get_link_ant_rssi(struct link *link) +{ + if (link->ant.rssi_ant && link->qual.rx_success) + return link->ant.rssi_ant; + return DEFAULT_RSSI; +} + +static inline int rt2x00_get_link_ant_rssi_history(struct link *link, + enum antenna ant) +{ + if (link->ant.rssi_history[ant - ANTENNA_A]) + return link->ant.rssi_history[ant - ANTENNA_A]; + return DEFAULT_RSSI; +} + +static inline int rt2x00_update_ant_rssi(struct link *link, int rssi) +{ + int old_rssi = link->ant.rssi_history[link->ant.active.rx - ANTENNA_A]; + link->ant.rssi_history[link->ant.active.rx - ANTENNA_A] = rssi; + return old_rssi; } /* diff --git a/drivers/net/wireless/rt2x00/rt2x00config.c b/drivers/net/wireless/rt2x00/rt2x00config.c index 04518b089bd..2b0edd20eea 100644 --- a/drivers/net/wireless/rt2x00/rt2x00config.c +++ b/drivers/net/wireless/rt2x00/rt2x00config.c @@ -94,6 +94,26 @@ void rt2x00lib_config_type(struct rt2x00_dev *rt2x00dev, const int type) rt2x00dev->ops->lib->config_type(rt2x00dev, type, tsf_sync); } +void rt2x00lib_config_antenna(struct rt2x00_dev *rt2x00dev, + enum antenna rx, enum antenna tx) +{ + struct rt2x00lib_conf libconf; + + libconf.ant.rx = rx; + libconf.ant.tx = tx; + + /* + * Write new antenna setup to device and reset the link tuner. + * The latter is required since we need to recalibrate the + * noise-sensitivity ratio for the new setup. + */ + rt2x00dev->ops->lib->config(rt2x00dev, CONFIG_UPDATE_ANTENNA, &libconf); + rt2x00lib_reset_link_tuner(rt2x00dev); + + rt2x00dev->link.ant.active.rx = libconf.ant.rx; + rt2x00dev->link.ant.active.tx = libconf.ant.tx; +} + void rt2x00lib_config(struct rt2x00_dev *rt2x00dev, struct ieee80211_conf *conf, const int force_config) { @@ -101,7 +121,7 @@ void rt2x00lib_config(struct rt2x00_dev *rt2x00dev, struct ieee80211_hw_mode *mode; struct ieee80211_rate *rate; struct antenna_setup *default_ant = &rt2x00dev->default_ant; - struct antenna_setup *active_ant = &rt2x00dev->link.active_ant; + struct antenna_setup *active_ant = &rt2x00dev->link.ant.active; int flags = 0; int short_slot_time; @@ -247,6 +267,6 @@ config: rt2x00dev->rx_status.freq = conf->freq; rt2x00dev->rx_status.channel = conf->channel; rt2x00dev->tx_power = conf->power_level; - rt2x00dev->link.active_ant.rx = libconf.ant.rx; - rt2x00dev->link.active_ant.tx = libconf.ant.tx; + rt2x00dev->link.ant.active.rx = libconf.ant.rx; + rt2x00dev->link.ant.active.tx = libconf.ant.tx; } diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c index 0f824b27f1e..360f03ae17a 100644 --- a/drivers/net/wireless/rt2x00/rt2x00dev.c +++ b/drivers/net/wireless/rt2x00/rt2x00dev.c @@ -193,6 +193,133 @@ void rt2x00lib_toggle_rx(struct rt2x00_dev *rt2x00dev, enum dev_state state) rt2x00lib_start_link_tuner(rt2x00dev); } +static void rt2x00lib_evaluate_antenna_sample(struct rt2x00_dev *rt2x00dev) +{ + enum antenna rx = rt2x00dev->link.ant.active.rx; + enum antenna tx = rt2x00dev->link.ant.active.tx; + int sample_a = + rt2x00_get_link_ant_rssi_history(&rt2x00dev->link, ANTENNA_A); + int sample_b = + rt2x00_get_link_ant_rssi_history(&rt2x00dev->link, ANTENNA_B); + + /* + * We are done sampling. Now we should evaluate the results. + */ + rt2x00dev->link.ant.flags &= ~ANTENNA_MODE_SAMPLE; + + /* + * During the last period we have sampled the RSSI + * from both antenna's. It now is time to determine + * which antenna demonstrated the best performance. + * When we are already on the antenna with the best + * performance, then there really is nothing for us + * left to do. + */ + if (sample_a == sample_b) + return; + + if (rt2x00dev->link.ant.flags & ANTENNA_RX_DIVERSITY) { + if (sample_a > sample_b && rx == ANTENNA_B) + rx = ANTENNA_A; + else if (rx == ANTENNA_A) + rx = ANTENNA_B; + } + + if (rt2x00dev->link.ant.flags & ANTENNA_TX_DIVERSITY) { + if (sample_a > sample_b && tx == ANTENNA_B) + tx = ANTENNA_A; + else if (tx == ANTENNA_A) + tx = ANTENNA_B; + } + + rt2x00lib_config_antenna(rt2x00dev, rx, tx); +} + +static void rt2x00lib_evaluate_antenna_eval(struct rt2x00_dev *rt2x00dev) +{ + enum antenna rx = rt2x00dev->link.ant.active.rx; + enum antenna tx = rt2x00dev->link.ant.active.tx; + int rssi_curr = rt2x00_get_link_ant_rssi(&rt2x00dev->link); + int rssi_old = rt2x00_update_ant_rssi(&rt2x00dev->link, rssi_curr); + + /* + * Legacy driver indicates that we should swap antenna's + * when the difference in RSSI is greater that 5. This + * also should be done when the RSSI was actually better + * then the previous sample. + * When the difference exceeds the threshold we should + * sample the rssi from the other antenna to make a valid + * comparison between the 2 antennas. + */ + if ((rssi_curr - rssi_old) > -5 || (rssi_curr - rssi_old) < 5) + return; + + rt2x00dev->link.ant.flags |= ANTENNA_MODE_SAMPLE; + + if (rt2x00dev->link.ant.flags & ANTENNA_RX_DIVERSITY) + rx = (rx == ANTENNA_A) ? ANTENNA_B : ANTENNA_A; + + if (rt2x00dev->link.ant.flags & ANTENNA_TX_DIVERSITY) + tx = (tx == ANTENNA_A) ? ANTENNA_B : ANTENNA_A; + + rt2x00lib_config_antenna(rt2x00dev, rx, tx); +} + +static void rt2x00lib_evaluate_antenna(struct rt2x00_dev *rt2x00dev) +{ + /* + * Determine if software diversity is enabled for + * either the TX or RX antenna (or both). + * Always perform this check since within the link + * tuner interval the configuration might have changed. + */ + rt2x00dev->link.ant.flags &= ~ANTENNA_RX_DIVERSITY; + rt2x00dev->link.ant.flags &= ~ANTENNA_TX_DIVERSITY; + + if (rt2x00dev->hw->conf.antenna_sel_rx == 0 && + rt2x00dev->default_ant.rx != ANTENNA_SW_DIVERSITY) + rt2x00dev->link.ant.flags |= ANTENNA_RX_DIVERSITY; + if (rt2x00dev->hw->conf.antenna_sel_tx == 0 && + rt2x00dev->default_ant.tx != ANTENNA_SW_DIVERSITY) + rt2x00dev->link.ant.flags |= ANTENNA_TX_DIVERSITY; + + if (!(rt2x00dev->link.ant.flags & ANTENNA_RX_DIVERSITY) && + !(rt2x00dev->link.ant.flags & ANTENNA_TX_DIVERSITY)) { + rt2x00dev->link.ant.flags &= ~ANTENNA_MODE_SAMPLE; + return; + } + + /* + * If we have only sampled the data over the last period + * we should now harvest the data. Otherwise just evaluate + * the data. The latter should only be performed once + * every 2 seconds. + */ + if (rt2x00dev->link.ant.flags & ANTENNA_MODE_SAMPLE) + rt2x00lib_evaluate_antenna_sample(rt2x00dev); + else if (rt2x00dev->link.count & 1) + rt2x00lib_evaluate_antenna_eval(rt2x00dev); +} + +static void rt2x00lib_update_link_stats(struct link *link, int rssi) +{ + int avg_rssi = rssi; + + /* + * Update global RSSI + */ + if (link->qual.avg_rssi) + avg_rssi = MOVING_AVERAGE(link->qual.avg_rssi, rssi, 8); + link->qual.avg_rssi = avg_rssi; + + /* + * Update antenna RSSI + */ + if (link->ant.rssi_ant) + rssi = MOVING_AVERAGE(link->ant.rssi_ant, rssi, 8); + link->ant.rssi_ant = rssi; +} + static void rt2x00lib_precalculate_link_signal(struct link_qual *qual) { if (qual->rx_failed || qual->rx_success) @@ -261,7 +388,6 @@ static void rt2x00lib_link_tuner(struct work_struct *work) * Update statistics. */ rt2x00dev->ops->lib->link_stats(rt2x00dev, &rt2x00dev->link.qual); - rt2x00dev->low_level_stats.dot11FCSErrorCount += rt2x00dev->link.qual.rx_failed; @@ -273,6 +399,11 @@ static void rt2x00lib_link_tuner(struct work_struct *work) rt2x00dev->ops->lib->link_tuner(rt2x00dev); /* + * Evaluate antenna setup. + */ + rt2x00lib_evaluate_antenna(rt2x00dev); + + /* * Precalculate a portion of the link signal which is * in based on the tx/rx success/failure counters. */ @@ -426,14 +557,15 @@ void rt2x00lib_rxdone(struct data_entry *entry, struct sk_buff *skb, } } - rt2x00_update_link_rssi(&rt2x00dev->link, desc->rssi); + rt2x00lib_update_link_stats(&rt2x00dev->link, desc->rssi); rt2x00dev->link.qual.rx_success++; + rx_status->rate = val; rx_status->signal = rt2x00lib_calculate_link_signal(rt2x00dev, desc->rssi); rx_status->ssi = desc->rssi; rx_status->flag = desc->flags; - rx_status->antenna = rt2x00dev->link.active_ant.rx; + rx_status->antenna = rt2x00dev->link.ant.active.rx; /* * Send frame to mac80211 diff --git a/drivers/net/wireless/rt2x00/rt2x00lib.h b/drivers/net/wireless/rt2x00/rt2x00lib.h index 06d9bc0015c..73194112f45 100644 --- a/drivers/net/wireless/rt2x00/rt2x00lib.h +++ b/drivers/net/wireless/rt2x00/rt2x00lib.h @@ -53,6 +53,8 @@ void rt2x00lib_uninitialize(struct rt2x00_dev *rt2x00dev); void rt2x00lib_config_mac_addr(struct rt2x00_dev *rt2x00dev, u8 *mac); void rt2x00lib_config_bssid(struct rt2x00_dev *rt2x00dev, u8 *bssid); void rt2x00lib_config_type(struct rt2x00_dev *rt2x00dev, const int type); +void rt2x00lib_config_antenna(struct rt2x00_dev *rt2x00dev, + enum antenna rx, enum antenna tx); void rt2x00lib_config(struct rt2x00_dev *rt2x00dev, struct ieee80211_conf *conf, const int force_config); |