iwlwifi: implement iwl5000_calc_rssi
This patch implements rssi calculation for 5000 HW.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-5000.c b/drivers/net/wireless/iwlwifi/iwl-5000.c
index 56dbc81..c5b104f 100644
--- a/drivers/net/wireless/iwlwifi/iwl-5000.c
+++ b/drivers/net/wireless/iwlwifi/iwl-5000.c
@@ -1459,6 +1459,44 @@
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 @@
.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 = {