From ae16fc3c3184bf27f0462e1951df918122498829 Mon Sep 17 00:00:00 2001 From: Wey-Yi Guy Date: Fri, 13 Nov 2009 11:56:30 -0800 Subject: [PATCH] iwlwifi: eliminate the possible 1/2 dBm tx power loss in 6x00 & 6x50 series In both 6x00 and 6x50 series, the enhanced/extended tx power table in EEPROM is used to set the max. tx power limit. This new tx power table is in 1/2 dBm format, which creates an issue of possibility of 1/2 dBm loss when driver set the tx power limit; because of driver keep track and report the tx power in dBm format. In order to prevent the 1/2 dBm loss, keep track of the true max tx power in 1/2 dBm format in driver; do the comparison and adjust the tx power if needed when send tx power command to uCode. Signed-off-by: Wey-Yi Guy Signed-off-by: Reinette Chatre Signed-off-by: John W. Linville --- drivers/net/wireless/iwlwifi/iwl-5000.c | 16 ++++++++ drivers/net/wireless/iwlwifi/iwl-dev.h | 1 + drivers/net/wireless/iwlwifi/iwl-eeprom.c | 49 ++++++++++++++++------- 3 files changed, 52 insertions(+), 14 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/iwl-5000.c b/drivers/net/wireless/iwlwifi/iwl-5000.c index 6eaf26b07636..48982fb44995 100644 --- a/drivers/net/wireless/iwlwifi/iwl-5000.c +++ b/drivers/net/wireless/iwlwifi/iwl-5000.c @@ -1250,6 +1250,22 @@ int iwl5000_send_tx_power(struct iwl_priv *priv) /* half dBm need to multiply */ tx_power_cmd.global_lmt = (s8)(2 * priv->tx_power_user_lmt); + + if (priv->tx_power_lmt_in_half_dbm && + priv->tx_power_lmt_in_half_dbm < tx_power_cmd.global_lmt) { + /* + * For the newer devices which using enhanced/extend tx power + * table in EEPROM, the format is in half dBm. driver need to + * convert to dBm format before report to mac80211. + * By doing so, there is a possibility of 1/2 dBm resolution + * lost. driver will perform "round-up" operation before + * reporting, but it will cause 1/2 dBm tx power over the + * regulatory limit. Perform the checking here, if the + * "tx_power_user_lmt" is higher than EEPROM value (in + * half-dBm format), lower the tx power based on EEPROM + */ + tx_power_cmd.global_lmt = priv->tx_power_lmt_in_half_dbm; + } tx_power_cmd.flags = IWL50_TX_POWER_NO_CLOSED; tx_power_cmd.srv_chan_lmt = IWL50_TX_POWER_AUTO; diff --git a/drivers/net/wireless/iwlwifi/iwl-dev.h b/drivers/net/wireless/iwlwifi/iwl-dev.h index 774a315996e6..a474383ec0b8 100644 --- a/drivers/net/wireless/iwlwifi/iwl-dev.h +++ b/drivers/net/wireless/iwlwifi/iwl-dev.h @@ -1247,6 +1247,7 @@ struct iwl_priv { /* TX Power */ s8 tx_power_user_lmt; s8 tx_power_device_lmt; + s8 tx_power_lmt_in_half_dbm; /* max tx power in half-dBm format */ #ifdef CONFIG_IWLWIFI_DEBUG diff --git a/drivers/net/wireless/iwlwifi/iwl-eeprom.c b/drivers/net/wireless/iwlwifi/iwl-eeprom.c index e42eb6499f0e..ac88ff042d46 100644 --- a/drivers/net/wireless/iwlwifi/iwl-eeprom.c +++ b/drivers/net/wireless/iwlwifi/iwl-eeprom.c @@ -762,7 +762,8 @@ static int iwl_mod_ht40_chan_info(struct iwl_priv *priv, * find the highest tx power from all chains for the channel */ static s8 iwl_get_max_txpower_avg(struct iwl_priv *priv, - struct iwl_eeprom_enhanced_txpwr *enhanced_txpower, int element) + struct iwl_eeprom_enhanced_txpwr *enhanced_txpower, + int element, s8 *max_txpower_in_half_dbm) { s8 max_txpower_avg = 0; /* (dBm) */ @@ -794,10 +795,14 @@ static s8 iwl_get_max_txpower_avg(struct iwl_priv *priv, (enhanced_txpower[element].mimo3_max > max_txpower_avg)) max_txpower_avg = enhanced_txpower[element].mimo3_max; - /* max. tx power in EEPROM is in 1/2 dBm format - * convert from 1/2 dBm to dBm + /* + * max. tx power in EEPROM is in 1/2 dBm format + * convert from 1/2 dBm to dBm (round-up convert) + * but we also do not want to loss 1/2 dBm resolution which + * will impact performance */ - return max_txpower_avg >> 1; + *max_txpower_in_half_dbm = max_txpower_avg; + return (max_txpower_avg & 0x01) + (max_txpower_avg >> 1); } /** @@ -806,7 +811,7 @@ static s8 iwl_get_max_txpower_avg(struct iwl_priv *priv, */ static s8 iwl_update_common_txpower(struct iwl_priv *priv, struct iwl_eeprom_enhanced_txpwr *enhanced_txpower, - int section, int element) + int section, int element, s8 *max_txpower_in_half_dbm) { struct iwl_channel_info *ch_info; int ch; @@ -820,20 +825,22 @@ static s8 iwl_update_common_txpower(struct iwl_priv *priv, if (element == EEPROM_TXPOWER_COMMON_HT40_INDEX) is_ht40 = true; max_txpower_avg = - iwl_get_max_txpower_avg(priv, enhanced_txpower, element); + iwl_get_max_txpower_avg(priv, enhanced_txpower, + element, max_txpower_in_half_dbm); + ch_info = priv->channel_info; for (ch = 0; ch < priv->channel_count; ch++) { /* find matching band and update tx power if needed */ if ((ch_info->band == enhinfo[section].band) && - (ch_info->max_power_avg < max_txpower_avg) && (!is_ht40)) { + (ch_info->max_power_avg < max_txpower_avg) && + (!is_ht40)) { /* Update regulatory-based run-time data */ ch_info->max_power_avg = ch_info->curr_txpow = - max_txpower_avg; + max_txpower_avg; ch_info->scan_power = max_txpower_avg; } if ((ch_info->band == enhinfo[section].band) && is_ht40 && - ch_info->ht40_max_power_avg && (ch_info->ht40_max_power_avg < max_txpower_avg)) { /* Update regulatory-based run-time data */ ch_info->ht40_max_power_avg = max_txpower_avg; @@ -849,7 +856,7 @@ static s8 iwl_update_common_txpower(struct iwl_priv *priv, */ static s8 iwl_update_channel_txpower(struct iwl_priv *priv, struct iwl_eeprom_enhanced_txpwr *enhanced_txpower, - int section, int element) + int section, int element, s8 *max_txpower_in_half_dbm) { struct iwl_channel_info *ch_info; int ch; @@ -858,7 +865,8 @@ static s8 iwl_update_channel_txpower(struct iwl_priv *priv, channel = enhinfo[section].iwl_eeprom_section_channel[element]; max_txpower_avg = - iwl_get_max_txpower_avg(priv, enhanced_txpower, element); + iwl_get_max_txpower_avg(priv, enhanced_txpower, + element, max_txpower_in_half_dbm); ch_info = priv->channel_info; for (ch = 0; ch < priv->channel_count; ch++) { @@ -872,7 +880,6 @@ static s8 iwl_update_channel_txpower(struct iwl_priv *priv, ch_info->scan_power = max_txpower_avg; } if ((enhinfo[section].is_ht40) && - (ch_info->ht40_max_power_avg) && (ch_info->ht40_max_power_avg < max_txpower_avg)) { /* Update regulatory-based run-time data */ ch_info->ht40_max_power_avg = max_txpower_avg; @@ -894,6 +901,7 @@ void iwlcore_eeprom_enhanced_txpower(struct iwl_priv *priv) struct iwl_eeprom_enhanced_txpwr *enhanced_txpower; u32 offset; s8 max_txpower_avg; /* (dBm) */ + s8 max_txpower_in_half_dbm; /* (half-dBm) */ /* Loop through all the sections * adjust bands and channel's max tx power @@ -920,16 +928,29 @@ void iwlcore_eeprom_enhanced_txpower(struct iwl_priv *priv) if (enhinfo[section].is_common) max_txpower_avg = iwl_update_common_txpower(priv, - enhanced_txpower, section, element); + enhanced_txpower, section, + element, + &max_txpower_in_half_dbm); else max_txpower_avg = iwl_update_channel_txpower(priv, - enhanced_txpower, section, element); + enhanced_txpower, section, + element, + &max_txpower_in_half_dbm); /* Update the tx_power_user_lmt to the highest power * supported by any channel */ if (max_txpower_avg > priv->tx_power_user_lmt) priv->tx_power_user_lmt = max_txpower_avg; + + /* + * Update the tx_power_lmt_in_half_dbm to + * the highest power supported by any channel + */ + if (max_txpower_in_half_dbm > + priv->tx_power_lmt_in_half_dbm) + priv->tx_power_lmt_in_half_dbm = + max_txpower_in_half_dbm; } } } -- 2.20.1