* Enable I/Q calibration each time we have correction results (we were only enabling calibration during reset). If we don't we commit the same results each time calibration routine is called. * Add some documentation and a TODO on nf calibration * Return -EAGAIN on noise floor timeout/failure Changes-licensed-under: ISC Signed-off-by: Nick Kossifidis <mickflemm@xxxxxxxxx> --- diff --git a/drivers/net/wireless/ath5k/phy.c b/drivers/net/wireless/ath5k/phy.c index cbc362d..dc05f98 100644 --- a/drivers/net/wireless/ath5k/phy.c +++ b/drivers/net/wireless/ath5k/phy.c @@ -2052,6 +2052,8 @@ int ath5k_hw_channel(struct ath5k_hw *ah, struct ieee80211_channel *channel) * http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL \ * &p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=7245893.PN.&OS=PN/7 * + * XXX: Since during noise floor calibration antennas are detached acording to + * the pattent, we should stop tx queues here. */ int ath5k_hw_noise_floor_calibration(struct ath5k_hw *ah, short freq) @@ -2061,7 +2063,7 @@ ath5k_hw_noise_floor_calibration(struct ath5k_hw *ah, short freq) s32 noise_floor; /* - * Enable noise floor calibration and wait until completion + * Enable noise floor calibration */ AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL, AR5K_PHY_AGCCTL_NF); @@ -2071,7 +2073,7 @@ ath5k_hw_noise_floor_calibration(struct ath5k_hw *ah, short freq) if (ret) { ATH5K_ERR(ah->ah_sc, "noise floor calibration timeout (%uMHz)\n", freq); - return ret; + return -EAGAIN; } /* Wait until the noise floor is calibrated and read the value */ @@ -2093,7 +2095,7 @@ ath5k_hw_noise_floor_calibration(struct ath5k_hw *ah, short freq) if (noise_floor > AR5K_TUNE_NOISE_FLOOR) { ATH5K_ERR(ah->ah_sc, "noise floor calibration failed (%uMHz)\n", freq); - return -EIO; + return -EAGAIN; } ah->ah_noise_floor = noise_floor; @@ -2206,38 +2208,66 @@ static int ath5k_hw_rf5110_calibrate(struct ath5k_hw *ah, } /* - * Perform a PHY calibration on RF5111/5112 + * Perform a PHY calibration on RF5111/5112 and newer chips */ static int ath5k_hw_rf511x_calibrate(struct ath5k_hw *ah, struct ieee80211_channel *channel) { u32 i_pwr, q_pwr; s32 iq_corr, i_coff, i_coffd, q_coff, q_coffd; + int i; ATH5K_TRACE(ah->ah_sc); if (!ah->ah_calibration || - ath5k_hw_reg_read(ah, AR5K_PHY_IQ) & AR5K_PHY_IQ_RUN) + ath5k_hw_reg_read(ah, AR5K_PHY_IQ) & AR5K_PHY_IQ_RUN) goto done; - ah->ah_calibration = false; + /* Calibration has finished, get the results and re-run */ + for (i = 0; i <= 10; i++) { + iq_corr = ath5k_hw_reg_read(ah, AR5K_PHY_IQRES_CAL_CORR); + i_pwr = ath5k_hw_reg_read(ah, AR5K_PHY_IQRES_CAL_PWR_I); + q_pwr = ath5k_hw_reg_read(ah, AR5K_PHY_IQRES_CAL_PWR_Q); + } - iq_corr = ath5k_hw_reg_read(ah, AR5K_PHY_IQRES_CAL_CORR); - i_pwr = ath5k_hw_reg_read(ah, AR5K_PHY_IQRES_CAL_PWR_I); - q_pwr = ath5k_hw_reg_read(ah, AR5K_PHY_IQRES_CAL_PWR_Q); i_coffd = ((i_pwr >> 1) + (q_pwr >> 1)) >> 7; - q_coffd = q_pwr >> 6; + q_coffd = q_pwr >> 7; + /* No correction */ if (i_coffd == 0 || q_coffd == 0) goto done; i_coff = ((-iq_corr) / i_coffd) & 0x3f; - q_coff = (((s32)i_pwr / q_coffd) - 64) & 0x1f; - /* Commit new IQ value */ + /* Boundary check */ + if (i_coff > 31) + i_coff = 31; + if (i_coff < -32) + i_coff = -32; + + q_coff = (((s32)i_pwr / q_coffd) - 128) & 0x1f; + + /* Boundary check */ + if (q_coff > 15) + q_coff = 15; + if (q_coff < -16) + q_coff = -16; + + /* Commit new I/Q value */ AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_IQ, AR5K_PHY_IQ_CORR_ENABLE | ((u32)q_coff) | ((u32)i_coff << AR5K_PHY_IQ_CORR_Q_I_COFF_S)); + /* Re-enable calibration -if we don't we'll commit + * the same values again and again */ + AR5K_REG_WRITE_BITS(ah, AR5K_PHY_IQ, + AR5K_PHY_IQ_CAL_NUM_LOG_MAX, 15); + AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_IQ, AR5K_PHY_IQ_RUN); + done: + + /* TODO: Separate noise floor calibration from I/Q calibration + * since noise floor calibration interrupts rx path while I/Q + * calibration doesn't. We don't need to run noise floor calibration + * as often as I/Q calibration.*/ ath5k_hw_noise_floor_calibration(ah, channel->center_freq); /* Request RF gain */ -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
