diff options
Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-5000.c')
-rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-5000.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-5000.c b/drivers/net/wireless/iwlwifi/iwl-5000.c index 56dbc8144a3..c5b104fd149 100644 --- a/drivers/net/wireless/iwlwifi/iwl-5000.c +++ b/drivers/net/wireless/iwlwifi/iwl-5000.c @@ -1459,6 +1459,44 @@ static void iwl5000_temperature(struct iwl_priv *priv) priv->temperature = le32_to_cpu(priv->statistics.general.temperature); } +/* Calc max signal level (dBm) among 3 possible receivers */ +static int iwl5000_calc_rssi(struct iwl_priv *priv, + struct iwl_rx_phy_res *rx_resp) +{ + /* data from PHY/DSP regarding signal strength, etc., + * contents are always there, not configurable by host + */ + struct iwl5000_non_cfg_phy *ncphy = + (struct iwl5000_non_cfg_phy *)rx_resp->non_cfg_phy_buf; + u32 val, rssi_a, rssi_b, rssi_c, max_rssi; + u8 agc; + + val = le32_to_cpu(ncphy->non_cfg_phy[IWL50_RX_RES_AGC_IDX]); + agc = (val & IWL50_OFDM_AGC_MSK) >> IWL50_OFDM_AGC_BIT_POS; + + /* Find max rssi among 3 possible receivers. + * These values are measured by the digital signal processor (DSP). + * They should stay fairly constant even as the signal strength varies, + * if the radio's automatic gain control (AGC) is working right. + * AGC value (see below) will provide the "interesting" info. + */ + val = le32_to_cpu(ncphy->non_cfg_phy[IWL50_RX_RES_RSSI_AB_IDX]); + rssi_a = (val & IWL50_OFDM_RSSI_A_MSK) >> IWL50_OFDM_RSSI_A_BIT_POS; + rssi_b = (val & IWL50_OFDM_RSSI_B_MSK) >> IWL50_OFDM_RSSI_B_BIT_POS; + val = le32_to_cpu(ncphy->non_cfg_phy[IWL50_RX_RES_RSSI_C_IDX]); + rssi_c = (val & IWL50_OFDM_RSSI_C_MSK) >> IWL50_OFDM_RSSI_C_BIT_POS; + + max_rssi = max_t(u32, rssi_a, rssi_b); + max_rssi = max_t(u32, max_rssi, rssi_c); + + IWL_DEBUG_STATS("Rssi In A %d B %d C %d Max %d AGC dB %d\n", + rssi_a, rssi_b, rssi_c, max_rssi, agc); + + /* dBm = max_rssi dB - agc dB - constant. + * Higher AGC (higher radio gain) means lower signal. */ + return max_rssi - agc - IWL_RSSI_OFFSET; +} + static struct iwl_hcmd_ops iwl5000_hcmd = { .rxon_assoc = iwl5000_send_rxon_assoc, }; @@ -1469,6 +1507,7 @@ static struct iwl_hcmd_utils_ops iwl5000_hcmd_utils = { .gain_computation = iwl5000_gain_computation, .chain_noise_reset = iwl5000_chain_noise_reset, .rts_tx_cmd_flag = iwl5000_rts_tx_cmd_flag, + .calc_rssi = iwl5000_calc_rssi, }; static struct iwl_lib_ops iwl5000_lib = { |