* 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 <[email protected]>
---
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 */
On Sun, 2008-07-20 at 06:47 +0300, Nick Kossifidis wrote:
> + * XXX: Since during noise floor calibration antennas are detached acording to
> + * the pattent, we should stop tx queues here.
Two spelling fixes: "according to the patent". What patent is that?
Can we use it legally?
--
Regards,
Pavel Roskin