From 84e3196ff867c623056eea02c11a45e046490d89 Mon Sep 17 00:00:00 2001 From: Ivo van Doorn Date: Sat, 20 Dec 2008 10:53:29 +0100 Subject: rt2x00: Move link tuning into seperate file Move link and antenna tuning into a seperate file named rt2x00link.c, this makes the interface to the link tuner a lot cleaner. Signed-off-by: Ivo van Doorn Signed-off-by: John W. Linville --- drivers/net/wireless/rt2x00/Makefile | 1 + drivers/net/wireless/rt2x00/rt2x00.h | 29 +-- drivers/net/wireless/rt2x00/rt2x00config.c | 5 +- drivers/net/wireless/rt2x00/rt2x00debug.c | 4 +- drivers/net/wireless/rt2x00/rt2x00dev.c | 303 +--------------------- drivers/net/wireless/rt2x00/rt2x00lib.h | 81 +++++- drivers/net/wireless/rt2x00/rt2x00link.c | 402 +++++++++++++++++++++++++++++ 7 files changed, 494 insertions(+), 331 deletions(-) create mode 100644 drivers/net/wireless/rt2x00/rt2x00link.c (limited to 'drivers') diff --git a/drivers/net/wireless/rt2x00/Makefile b/drivers/net/wireless/rt2x00/Makefile index 917cb4f3b038..f22d808d8c51 100644 --- a/drivers/net/wireless/rt2x00/Makefile +++ b/drivers/net/wireless/rt2x00/Makefile @@ -2,6 +2,7 @@ rt2x00lib-y += rt2x00dev.o rt2x00lib-y += rt2x00mac.o rt2x00lib-y += rt2x00config.o rt2x00lib-y += rt2x00queue.o +rt2x00lib-y += rt2x00link.o rt2x00lib-$(CONFIG_RT2X00_LIB_DEBUGFS) += rt2x00debug.o rt2x00lib-$(CONFIG_RT2X00_LIB_CRYPTO) += rt2x00crypto.o rt2x00lib-$(CONFIG_RT2X00_LIB_RFKILL) += rt2x00rfkill.o diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h index 39ecf3b82ca1..19c068727a85 100644 --- a/drivers/net/wireless/rt2x00/rt2x00.h +++ b/drivers/net/wireless/rt2x00/rt2x00.h @@ -212,7 +212,7 @@ struct link_qual { * (WEIGHT_TX * tx_percentage) + * (WEIGHT_RX * rx_percentage)) / 100 * - * This value should then be checked to not be greated then 100. + * This value should then be checked to not be greater then 100. */ int rx_percentage; int rx_success; @@ -318,33 +318,6 @@ static inline int rt2x00_get_link_rssi(struct link *link) 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 void rt2x00_reset_link_ant_rssi(struct link *link) -{ - link->ant.rssi_ant = 0; -} - -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; -} - /* * Interface structure * Per interface configuration details, this structure diff --git a/drivers/net/wireless/rt2x00/rt2x00config.c b/drivers/net/wireless/rt2x00/rt2x00config.c index e66fb316cd61..2f4cb8de9981 100644 --- a/drivers/net/wireless/rt2x00/rt2x00config.c +++ b/drivers/net/wireless/rt2x00/rt2x00config.c @@ -152,8 +152,7 @@ void rt2x00lib_config_antenna(struct rt2x00_dev *rt2x00dev, */ rt2x00dev->ops->lib->config_ant(rt2x00dev, ant); - rt2x00lib_reset_link_tuner(rt2x00dev); - rt2x00_reset_link_ant_rssi(&rt2x00dev->link); + rt2x00link_reset_tuner(rt2x00dev, true); memcpy(active, ant, sizeof(*ant)); @@ -191,7 +190,7 @@ void rt2x00lib_config(struct rt2x00_dev *rt2x00dev, * which means we need to reset the link tuner. */ if (ieee80211_flags & IEEE80211_CONF_CHANGE_CHANNEL) - rt2x00lib_reset_link_tuner(rt2x00dev); + rt2x00link_reset_tuner(rt2x00dev, false); rt2x00dev->curr_band = conf->channel->band; rt2x00dev->tx_power = conf->power_level; diff --git a/drivers/net/wireless/rt2x00/rt2x00debug.c b/drivers/net/wireless/rt2x00/rt2x00debug.c index 54dd10060bf1..cc1940605349 100644 --- a/drivers/net/wireless/rt2x00/rt2x00debug.c +++ b/drivers/net/wireless/rt2x00/rt2x00debug.c @@ -130,9 +130,11 @@ struct rt2x00debug_intf { }; void rt2x00debug_update_crypto(struct rt2x00_dev *rt2x00dev, - enum cipher cipher, enum rx_crypto status) + struct rxdone_entry_desc *rxdesc) { struct rt2x00debug_intf *intf = rt2x00dev->debugfs_intf; + enum cipher cipher = rxdesc->cipher; + enum rx_crypto status = rxdesc->cipher_status; if (cipher == CIPHER_TKIP_NO_MIC) cipher = CIPHER_TKIP; diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c index 87c0f2c83077..81d7fc8635d3 100644 --- a/drivers/net/wireless/rt2x00/rt2x00dev.c +++ b/drivers/net/wireless/rt2x00/rt2x00dev.c @@ -29,60 +29,6 @@ #include "rt2x00.h" #include "rt2x00lib.h" -/* - * Link tuning handlers - */ -void rt2x00lib_reset_link_tuner(struct rt2x00_dev *rt2x00dev) -{ - if (!test_bit(DEVICE_STATE_ENABLED_RADIO, &rt2x00dev->flags)) - return; - - /* - * Reset link information. - * Both the currently active vgc level as well as - * the link tuner counter should be reset. Resetting - * the counter is important for devices where the - * device should only perform link tuning during the - * first minute after being enabled. - */ - rt2x00dev->link.count = 0; - rt2x00dev->link.vgc_level = 0; - - /* - * Reset the link tuner. - */ - rt2x00dev->ops->lib->reset_tuner(rt2x00dev); -} - -static void rt2x00lib_start_link_tuner(struct rt2x00_dev *rt2x00dev) -{ - /* - * Clear all (possibly) pre-existing quality statistics. - */ - memset(&rt2x00dev->link.qual, 0, sizeof(rt2x00dev->link.qual)); - - /* - * The RX and TX percentage should start at 50% - * this will assure we will get at least get some - * decent value when the link tuner starts. - * The value will be dropped and overwritten with - * the correct (measured )value anyway during the - * first run of the link tuner. - */ - rt2x00dev->link.qual.rx_percentage = 50; - rt2x00dev->link.qual.tx_percentage = 50; - - rt2x00lib_reset_link_tuner(rt2x00dev); - - queue_delayed_work(rt2x00dev->hw->workqueue, - &rt2x00dev->link.work, LINK_TUNE_INTERVAL); -} - -static void rt2x00lib_stop_link_tuner(struct rt2x00_dev *rt2x00dev) -{ - cancel_delayed_work_sync(&rt2x00dev->link.work); -} - /* * Radio control handlers. */ @@ -161,238 +107,15 @@ void rt2x00lib_toggle_rx(struct rt2x00_dev *rt2x00dev, enum dev_state state) * When we are disabling the RX, we should also stop the link tuner. */ if (state == STATE_RADIO_RX_OFF) - rt2x00lib_stop_link_tuner(rt2x00dev); + rt2x00link_stop_tuner(rt2x00dev); rt2x00dev->ops->lib->set_device_state(rt2x00dev, state); /* * When we are enabling the RX, we should also start the link tuner. */ - if (state == STATE_RADIO_RX_ON && - (rt2x00dev->intf_ap_count || rt2x00dev->intf_sta_count)) - rt2x00lib_start_link_tuner(rt2x00dev); -} - -static void rt2x00lib_evaluate_antenna_sample(struct rt2x00_dev *rt2x00dev) -{ - struct antenna_setup ant; - 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); - - memcpy(&ant, &rt2x00dev->link.ant.active, sizeof(ant)); - - /* - * 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) - ant.rx = (sample_a > sample_b) ? ANTENNA_A : ANTENNA_B; - - if (rt2x00dev->link.ant.flags & ANTENNA_TX_DIVERSITY) - ant.tx = (sample_a > sample_b) ? ANTENNA_A : ANTENNA_B; - - rt2x00lib_config_antenna(rt2x00dev, &ant); -} - -static void rt2x00lib_evaluate_antenna_eval(struct rt2x00_dev *rt2x00dev) -{ - struct antenna_setup ant; - int rssi_curr = rt2x00_get_link_ant_rssi(&rt2x00dev->link); - int rssi_old = rt2x00_update_ant_rssi(&rt2x00dev->link, rssi_curr); - - memcpy(&ant, &rt2x00dev->link.ant.active, sizeof(ant)); - - /* - * 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 (abs(rssi_curr - rssi_old) < 5) - return; - - rt2x00dev->link.ant.flags |= ANTENNA_MODE_SAMPLE; - - if (rt2x00dev->link.ant.flags & ANTENNA_RX_DIVERSITY) - ant.rx = (ant.rx == ANTENNA_A) ? ANTENNA_B : ANTENNA_A; - - if (rt2x00dev->link.ant.flags & ANTENNA_TX_DIVERSITY) - ant.tx = (ant.tx == ANTENNA_A) ? ANTENNA_B : ANTENNA_A; - - rt2x00lib_config_antenna(rt2x00dev, &ant); -} - -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->default_ant.rx == ANTENNA_SW_DIVERSITY) - rt2x00dev->link.ant.flags |= ANTENNA_RX_DIVERSITY; - if (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 = 0; - 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) - qual->rx_percentage = - (qual->rx_success * 100) / - (qual->rx_failed + qual->rx_success); - else - qual->rx_percentage = 50; - - if (qual->tx_failed || qual->tx_success) - qual->tx_percentage = - (qual->tx_success * 100) / - (qual->tx_failed + qual->tx_success); - else - qual->tx_percentage = 50; - - qual->rx_success = 0; - qual->rx_failed = 0; - qual->tx_success = 0; - qual->tx_failed = 0; -} - -static int rt2x00lib_calculate_link_signal(struct rt2x00_dev *rt2x00dev, - int rssi) -{ - int rssi_percentage = 0; - int signal; - - /* - * We need a positive value for the RSSI. - */ - if (rssi < 0) - rssi += rt2x00dev->rssi_offset; - - /* - * Calculate the different percentages, - * which will be used for the signal. - */ - if (rt2x00dev->rssi_offset) - rssi_percentage = (rssi * 100) / rt2x00dev->rssi_offset; - - /* - * Add the individual percentages and use the WEIGHT - * defines to calculate the current link signal. - */ - signal = ((WEIGHT_RSSI * rssi_percentage) + - (WEIGHT_TX * rt2x00dev->link.qual.tx_percentage) + - (WEIGHT_RX * rt2x00dev->link.qual.rx_percentage)) / 100; - - return (signal > 100) ? 100 : signal; -} - -static void rt2x00lib_link_tuner(struct work_struct *work) -{ - struct rt2x00_dev *rt2x00dev = - container_of(work, struct rt2x00_dev, link.work.work); - - /* - * When the radio is shutting down we should - * immediately cease all link tuning. - */ - if (!test_bit(DEVICE_STATE_ENABLED_RADIO, &rt2x00dev->flags)) - return; - - /* - * Update statistics. - */ - rt2x00dev->ops->lib->link_stats(rt2x00dev, &rt2x00dev->link.qual); - rt2x00dev->low_level_stats.dot11FCSErrorCount += - rt2x00dev->link.qual.rx_failed; - - /* - * Only perform the link tuning when Link tuning - * has been enabled (This could have been disabled from the EEPROM). - */ - if (!test_bit(CONFIG_DISABLE_LINK_TUNING, &rt2x00dev->flags)) - rt2x00dev->ops->lib->link_tuner(rt2x00dev); - - /* - * Precalculate a portion of the link signal which is - * in based on the tx/rx success/failure counters. - */ - rt2x00lib_precalculate_link_signal(&rt2x00dev->link.qual); - - /* - * Send a signal to the led to update the led signal strength. - */ - rt2x00leds_led_quality(rt2x00dev, rt2x00dev->link.qual.avg_rssi); - - /* - * Evaluate antenna setup, make this the last step since this could - * possibly reset some statistics. - */ - rt2x00lib_evaluate_antenna(rt2x00dev); - - /* - * Increase tuner counter, and reschedule the next link tuner run. - */ - rt2x00dev->link.count++; - queue_delayed_work(rt2x00dev->hw->workqueue, - &rt2x00dev->link.work, LINK_TUNE_INTERVAL); + if (state == STATE_RADIO_RX_ON) + rt2x00link_start_tuner(rt2x00dev); } static void rt2x00lib_packetfilter_scheduled(struct work_struct *work) @@ -597,7 +320,6 @@ void rt2x00lib_rxdone(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb; struct ieee80211_rx_status *rx_status = &rt2x00dev->rx_status; struct ieee80211_supported_band *sband; - struct ieee80211_hdr *hdr; const struct rt2x00_rate *rate; unsigned int header_length; unsigned int align; @@ -674,23 +396,14 @@ void rt2x00lib_rxdone(struct rt2x00_dev *rt2x00dev, } /* - * Only update link status if this is a beacon frame carrying our bssid. + * Update extra components */ - hdr = (struct ieee80211_hdr *)entry->skb->data; - if (ieee80211_is_beacon(hdr->frame_control) && - (rxdesc.dev_flags & RXDONE_MY_BSS)) - rt2x00lib_update_link_stats(&rt2x00dev->link, rxdesc.rssi); - - rt2x00debug_update_crypto(rt2x00dev, - rxdesc.cipher, - rxdesc.cipher_status); - - rt2x00dev->link.qual.rx_success++; + rt2x00link_update_stats(rt2x00dev, entry->skb, &rxdesc); + rt2x00debug_update_crypto(rt2x00dev, &rxdesc); rx_status->mactime = rxdesc.timestamp; rx_status->rate_idx = idx; - rx_status->qual = - rt2x00lib_calculate_link_signal(rt2x00dev, rxdesc.rssi); + rx_status->qual = rt2x00link_calculate_signal(rt2x00dev, rxdesc.rssi); rx_status->signal = rxdesc.rssi; rx_status->flag = rxdesc.flags; rx_status->antenna = rt2x00dev->link.ant.active.rx; @@ -1083,7 +796,6 @@ int rt2x00lib_probe_dev(struct rt2x00_dev *rt2x00dev) */ INIT_WORK(&rt2x00dev->intf_work, rt2x00lib_intf_scheduled); INIT_WORK(&rt2x00dev->filter_work, rt2x00lib_packetfilter_scheduled); - INIT_DELAYED_WORK(&rt2x00dev->link.work, rt2x00lib_link_tuner); /* * Allocate queue array. @@ -1104,6 +816,7 @@ int rt2x00lib_probe_dev(struct rt2x00_dev *rt2x00dev) /* * Register extra components. */ + rt2x00link_register(rt2x00dev); rt2x00leds_register(rt2x00dev); rt2x00rfkill_allocate(rt2x00dev); rt2x00debug_register(rt2x00dev); diff --git a/drivers/net/wireless/rt2x00/rt2x00lib.h b/drivers/net/wireless/rt2x00/rt2x00lib.h index 86cd26fbf769..fccaffde6f55 100644 --- a/drivers/net/wireless/rt2x00/rt2x00lib.h +++ b/drivers/net/wireless/rt2x00/rt2x00lib.h @@ -63,7 +63,6 @@ static inline const struct rt2x00_rate *rt2x00_get_rate(const u16 hw_value) int rt2x00lib_enable_radio(struct rt2x00_dev *rt2x00dev); void rt2x00lib_disable_radio(struct rt2x00_dev *rt2x00dev); void rt2x00lib_toggle_rx(struct rt2x00_dev *rt2x00dev, enum dev_state state); -void rt2x00lib_reset_link_tuner(struct rt2x00_dev *rt2x00dev); /* * Initialization handlers. @@ -154,6 +153,81 @@ void rt2x00queue_uninitialize(struct rt2x00_dev *rt2x00dev); int rt2x00queue_allocate(struct rt2x00_dev *rt2x00dev); void rt2x00queue_free(struct rt2x00_dev *rt2x00dev); +/** + * rt2x00link_update_stats - Update link statistics from RX frame + * @rt2x00dev: Pointer to &struct rt2x00_dev. + * @skb: Received frame + * @rxdesc: Received frame descriptor + * + * Update link statistics based on the information from the + * received frame descriptor. + */ +void rt2x00link_update_stats(struct rt2x00_dev *rt2x00dev, + struct sk_buff *skb, + struct rxdone_entry_desc *rxdesc); + +/** + * rt2x00link_calculate_signal - Calculate signal quality + * @rt2x00dev: Pointer to &struct rt2x00_dev. + * @rssi: RX Frame RSSI + * + * Calculate the signal quality of a frame based on the rssi + * measured during the receiving of the frame and the global + * link quality statistics measured since the start of the + * link tuning. The result is a value between 0 and 100 which + * is an indication of the signal quality. + */ +int rt2x00link_calculate_signal(struct rt2x00_dev *rt2x00dev, int rssi); + +/** + * rt2x00link_start_tuner - Start periodic link tuner work + * @rt2x00dev: Pointer to &struct rt2x00_dev. + * + * This start the link tuner periodic work, this work will + * be executed periodically until &rt2x00link_stop_tuner has + * been called. + */ +void rt2x00link_start_tuner(struct rt2x00_dev *rt2x00dev); + +/** + * rt2x00link_stop_tuner - Stop periodic link tuner work + * @rt2x00dev: Pointer to &struct rt2x00_dev. + * + * After this function completed the link tuner will not + * be running until &rt2x00link_start_tuner is called. + */ +void rt2x00link_stop_tuner(struct rt2x00_dev *rt2x00dev); + +/** + * rt2x00link_reset_tuner - Reset periodic link tuner work + * @rt2x00dev: Pointer to &struct rt2x00_dev. + * @antenna: Should the antenna tuning also be reset + * + * The VGC limit configured in the hardware will be reset to 0 + * which forces the driver to rediscover the correct value for + * the current association. This is needed when configuration + * options have changed which could drastically change the + * SNR level or link quality (i.e. changing the antenna setting). + * + * Resetting the link tuner will also cause the periodic work counter + * to be reset. Any driver which has a fixed limit on the number + * of rounds the link tuner is supposed to work will accept the + * tuner actions again if this limit was previously reached. + * + * If @antenna is set to true a the software antenna diversity + * tuning will also be reset. + */ +void rt2x00link_reset_tuner(struct rt2x00_dev *rt2x00dev, bool antenna); + +/** + * rt2x00link_register - Initialize link tuning functionality + * @rt2x00dev: Pointer to &struct rt2x00_dev. + * + * Initialize work structure and all link tuning related + * paramters. This will not start the link tuning process itself. + */ +void rt2x00link_register(struct rt2x00_dev *rt2x00dev); + /* * Firmware handlers. */ @@ -179,7 +253,7 @@ void rt2x00debug_deregister(struct rt2x00_dev *rt2x00dev); void rt2x00debug_dump_frame(struct rt2x00_dev *rt2x00dev, enum rt2x00_dump_type type, struct sk_buff *skb); void rt2x00debug_update_crypto(struct rt2x00_dev *rt2x00dev, - enum cipher cipher, enum rx_crypto status); + struct rxdone_entry_desc *rxdesc); #else static inline void rt2x00debug_register(struct rt2x00_dev *rt2x00dev) { @@ -196,8 +270,7 @@ static inline void rt2x00debug_dump_frame(struct rt2x00_dev *rt2x00dev, } static inline void rt2x00debug_update_crypto(struct rt2x00_dev *rt2x00dev, - enum cipher cipher, - enum rx_crypto status) + struct rxdone_entry_desc *rxdesc) { } #endif /* CONFIG_RT2X00_LIB_DEBUGFS */ diff --git a/drivers/net/wireless/rt2x00/rt2x00link.c b/drivers/net/wireless/rt2x00/rt2x00link.c new file mode 100644 index 000000000000..0462d5ab6e97 --- /dev/null +++ b/drivers/net/wireless/rt2x00/rt2x00link.c @@ -0,0 +1,402 @@ +/* + Copyright (C) 2004 - 2008 rt2x00 SourceForge Project + + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + 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., + 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +/* + Module: rt2x00lib + Abstract: rt2x00 generic link tuning routines. + */ + +#include +#include + +#include "rt2x00.h" +#include "rt2x00lib.h" + +static int rt2x00link_antenna_get_link_rssi(struct rt2x00_dev *rt2x00dev) +{ + struct link_ant *ant = &rt2x00dev->link.ant; + + if (ant->rssi_ant && rt2x00dev->link.qual.rx_success) + return ant->rssi_ant; + return DEFAULT_RSSI; +} + +static int rt2x00link_antenna_get_rssi_history(struct rt2x00_dev *rt2x00dev, + enum antenna antenna) +{ + struct link_ant *ant = &rt2x00dev->link.ant; + + if (ant->rssi_history[antenna - ANTENNA_A]) + return ant->rssi_history[antenna - ANTENNA_A]; + return DEFAULT_RSSI; +} +/* Small wrapper for rt2x00link_antenna_get_rssi_history() */ +#define rt2x00link_antenna_get_rssi_rx_history(__dev) \ + rt2x00link_antenna_get_rssi_history((__dev), \ + (__dev)->link.ant.active.rx) +#define rt2x00link_antenna_get_rssi_tx_history(__dev) \ + rt2x00link_antenna_get_rssi_history((__dev), \ + (__dev)->link.ant.active.tx) + +static void rt2x00link_antenna_update_rssi_history(struct rt2x00_dev *rt2x00dev, + enum antenna antenna, + int rssi) +{ + struct link_ant *ant = &rt2x00dev->link.ant; + ant->rssi_history[ant->active.rx - ANTENNA_A] = rssi; +} +/* Small wrapper for rt2x00link_antenna_get_rssi_history() */ +#define rt2x00link_antenna_update_rssi_rx_history(__dev, __rssi) \ + rt2x00link_antenna_update_rssi_history((__dev), \ + (__dev)->link.ant.active.rx, \ + (__rssi)) +#define rt2x00link_antenna_update_rssi_tx_history(__dev, __rssi) \ + rt2x00link_antenna_update_rssi_history((__dev), \ + (__dev)->link.ant.active.tx, \ + (__rssi)) + +static void rt2x00link_antenna_reset(struct rt2x00_dev *rt2x00dev) +{ + rt2x00dev->link.ant.rssi_ant = 0; +} + +static void rt2x00lib_antenna_diversity_sample(struct rt2x00_dev *rt2x00dev) +{ + struct link_ant *ant = &rt2x00dev->link.ant; + struct antenna_setup new_ant; + int sample_a = rt2x00link_antenna_get_rssi_history(rt2x00dev, ANTENNA_A); + int sample_b = rt2x00link_antenna_get_rssi_history(rt2x00dev, ANTENNA_B); + + memcpy(&new_ant, &ant->active, sizeof(new_ant)); + + /* + * We are done sampling. Now we should evaluate the results. + */ + 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 (ant->flags & ANTENNA_RX_DIVERSITY) + new_ant.rx = (sample_a > sample_b) ? ANTENNA_A : ANTENNA_B; + + if (ant->flags & ANTENNA_TX_DIVERSITY) + new_ant.tx = (sample_a > sample_b) ? ANTENNA_A : ANTENNA_B; + + rt2x00lib_config_antenna(rt2x00dev, &new_ant); +} + +static void rt2x00lib_antenna_diversity_eval(struct rt2x00_dev *rt2x00dev) +{ + struct link_ant *ant = &rt2x00dev->link.ant; + struct antenna_setup new_ant; + int rssi_curr; + int rssi_old; + + memcpy(&new_ant, &ant->active, sizeof(new_ant)); + + /* + * Get current RSSI value along with the historical value, + * after that update the history with the current value. + */ + rssi_curr = rt2x00link_antenna_get_link_rssi(rt2x00dev); + rssi_old = rt2x00link_antenna_get_rssi_rx_history(rt2x00dev); + rt2x00link_antenna_update_rssi_rx_history(rt2x00dev, 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 (abs(rssi_curr - rssi_old) < 5) + return; + + ant->flags |= ANTENNA_MODE_SAMPLE; + + if (ant->flags & ANTENNA_RX_DIVERSITY) + new_ant.rx = (new_ant.rx == ANTENNA_A) ? ANTENNA_B : ANTENNA_A; + + if (ant->flags & ANTENNA_TX_DIVERSITY) + new_ant.tx = (new_ant.tx == ANTENNA_A) ? ANTENNA_B : ANTENNA_A; + + rt2x00lib_config_antenna(rt2x00dev, &new_ant); +} + +static void rt2x00lib_antenna_diversity(struct rt2x00_dev *rt2x00dev) +{ + struct link_ant *ant = &rt2x00dev->link.ant; + + /* + * 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. + */ + ant->flags &= ~ANTENNA_RX_DIVERSITY; + ant->flags &= ~ANTENNA_TX_DIVERSITY; + + if (rt2x00dev->default_ant.rx == ANTENNA_SW_DIVERSITY) + ant->flags |= ANTENNA_RX_DIVERSITY; + if (rt2x00dev->default_ant.tx == ANTENNA_SW_DIVERSITY) + ant->flags |= ANTENNA_TX_DIVERSITY; + + if (!(ant->flags & ANTENNA_RX_DIVERSITY) && + !(ant->flags & ANTENNA_TX_DIVERSITY)) { + ant->flags = 0; + 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 (ant->flags & ANTENNA_MODE_SAMPLE) + rt2x00lib_antenna_diversity_sample(rt2x00dev); + else if (rt2x00dev->link.count & 1) + rt2x00lib_antenna_diversity_eval(rt2x00dev); +} + +void rt2x00link_update_stats(struct rt2x00_dev *rt2x00dev, + struct sk_buff *skb, + struct rxdone_entry_desc *rxdesc) +{ + struct link_qual *qual = &rt2x00dev->link.qual; + struct link_ant *ant = &rt2x00dev->link.ant; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; + int avg_rssi = rxdesc->rssi; + int ant_rssi = rxdesc->rssi; + + /* + * Frame was received successfully since non-succesfull + * frames would have been dropped by the hardware. + */ + qual->rx_success++; + + /* + * We are only interested in quality statistics from + * beacons which came from the BSS which we are + * associated with. + */ + if (!ieee80211_is_beacon(hdr->frame_control) || + !(rxdesc->dev_flags & RXDONE_MY_BSS)) + return; + + /* + * Update global RSSI + */ + if (qual->avg_rssi) + avg_rssi = MOVING_AVERAGE(qual->avg_rssi, rxdesc->rssi, 8); + qual->avg_rssi = avg_rssi; + + /* + * Update antenna RSSI + */ + if (ant->rssi_ant) + ant_rssi = MOVING_AVERAGE(ant->rssi_ant, rxdesc->rssi, 8); + ant->rssi_ant = ant_rssi; +} + +static void rt2x00link_precalculate_signal(struct rt2x00_dev *rt2x00dev) +{ + struct link_qual *qual = &rt2x00dev->link.qual; + + if (qual->rx_failed || qual->rx_success) + qual->rx_percentage = + (qual->rx_success * 100) / + (qual->rx_failed + qual->rx_success); + else + qual->rx_percentage = 50; + + if (qual->tx_failed || qual->tx_success) + qual->tx_percentage = + (qual->tx_success * 100) / + (qual->tx_failed + qual->tx_success); + else + qual->tx_percentage = 50; + + qual->rx_success = 0; + qual->rx_failed = 0; + qual->tx_success = 0; + qual->tx_failed = 0; +} + +int rt2x00link_calculate_signal(struct rt2x00_dev *rt2x00dev, int rssi) +{ + struct link_qual *qual = &rt2x00dev->link.qual; + int rssi_percentage = 0; + int signal; + + /* + * We need a positive value for the RSSI. + */ + if (rssi < 0) + rssi += rt2x00dev->rssi_offset; + + /* + * Calculate the different percentages, + * which will be used for the signal. + */ + rssi_percentage = (rssi * 100) / rt2x00dev->rssi_offset; + + /* + * Add the individual percentages and use the WEIGHT + * defines to calculate the current link signal. + */ + signal = ((WEIGHT_RSSI * rssi_percentage) + + (WEIGHT_TX * qual->tx_percentage) + + (WEIGHT_RX * qual->rx_percentage)) / 100; + + return max_t(int, signal, 100); +} + +void rt2x00link_start_tuner(struct rt2x00_dev *rt2x00dev) +{ + struct link_qual *qual = &rt2x00dev->link.qual; + + /* + * Link tuning should only be performed when + * an active sta or master interface exists. + * Single monitor mode interfaces should never have + * work with link tuners. + */ + if (!rt2x00dev->intf_ap_count && !rt2x00dev->intf_sta_count) + return; + + /* + * Clear all (possibly) pre-existing quality statistics. + */ + memset(qual, 0, sizeof(*qual)); + + /* + * The RX and TX percentage should start at 50% + * this will assure we will get at least get some + * decent value when the link tuner starts. + * The value will be dropped and overwritten with + * the correct (measured) value anyway during the + * first run of the link tuner. + */ + qual->rx_percentage = 50; + qual->tx_percentage = 50; + + rt2x00link_reset_tuner(rt2x00dev, false); + + queue_delayed_work(rt2x00dev->hw->workqueue, + &rt2x00dev->link.work, LINK_TUNE_INTERVAL); +} + +void rt2x00link_stop_tuner(struct rt2x00_dev *rt2x00dev) +{ + cancel_delayed_work_sync(&rt2x00dev->link.work); +} + +void rt2x00link_reset_tuner(struct rt2x00_dev *rt2x00dev, bool antenna) +{ + if (!test_bit(DEVICE_STATE_ENABLED_RADIO, &rt2x00dev->flags)) + return; + + /* + * Reset link information. + * Both the currently active vgc level as well as + * the link tuner counter should be reset. Resetting + * the counter is important for devices where the + * device should only perform link tuning during the + * first minute after being enabled. + */ + rt2x00dev->link.count = 0; + rt2x00dev->link.vgc_level = 0; + + /* + * Reset the link tuner. + */ + rt2x00dev->ops->lib->reset_tuner(rt2x00dev); + + if (antenna) + rt2x00link_antenna_reset(rt2x00dev); +} + +static void rt2x00link_tuner(struct work_struct *work) +{ + struct rt2x00_dev *rt2x00dev = + container_of(work, struct rt2x00_dev, link.work.work); + struct link_qual *qual = &rt2x00dev->link.qual; + + /* + * When the radio is shutting down we should + * immediately cease all link tuning. + */ + if (!test_bit(DEVICE_STATE_ENABLED_RADIO, &rt2x00dev->flags)) + return; + + /* + * Update statistics. + */ + rt2x00dev->ops->lib->link_stats(rt2x00dev, qual); + rt2x00dev->low_level_stats.dot11FCSErrorCount += qual->rx_failed; + + /* + * Only perform the link tuning when Link tuning + * has been enabled (This could have been disabled from the EEPROM). + */ + if (!test_bit(CONFIG_DISABLE_LINK_TUNING, &rt2x00dev->flags)) + rt2x00dev->ops->lib->link_tuner(rt2x00dev); + + /* + * Precalculate a portion of the link signal which is + * in based on the tx/rx success/failure counters. + */ + rt2x00link_precalculate_signal(rt2x00dev); + + /* + * Send a signal to the led to update the led signal strength. + */ + rt2x00leds_led_quality(rt2x00dev, qual->avg_rssi); + + /* + * Evaluate antenna setup, make this the last step since this could + * possibly reset some statistics. + */ + rt2x00lib_antenna_diversity(rt2x00dev); + + /* + * Increase tuner counter, and reschedule the next link tuner run. + */ + rt2x00dev->link.count++; + queue_delayed_work(rt2x00dev->hw->workqueue, + &rt2x00dev->link.work, LINK_TUNE_INTERVAL); +} + +void rt2x00link_register(struct rt2x00_dev *rt2x00dev) +{ + INIT_DELAYED_WORK(&rt2x00dev->link.work, rt2x00link_tuner); +} -- cgit v1.2.2