ath5k: Allow user/driver to set txpower

* Now that we have regulatory control enable the driver to set
 txpower on hw

 * Also use txpower table offset so that we can match
 power range set by user/driver with indices on power table.

 Tested 2 different cards (a CM9 and an RF5112-based ubnt) and got
 the same output using a remote machine to measure per-packet rssi
 (conected the cards using attenuators). I also switched between
 various tx power levels and i saw an equal power change on the remote
 machine (so txpower changes as expected) and verified that we have
 the same output on each rate.
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath5k/ath5k.h

@@ -1100,11 +1100,12 @@ struct ath5k_hw {
 		/* Values in 0.25dB units */
 		s16		txp_min_pwr;
 		s16		txp_max_pwr;
+		/* Values in 0.5dB units */
 		s16		txp_offset;
 		s16		txp_ofdm;
-		/* Values in dB units */
-		s16		txp_cck_ofdm_pwr_delta;
 		s16		txp_cck_ofdm_gainf_delta;
+		/* Value in dB units */
+		s16		txp_cck_ofdm_pwr_delta;
 	} ah_txpower;
 
 	struct {
@@ -1271,7 +1272,7 @@ extern unsigned int ath5k_hw_get_def_antenna(struct ath5k_hw *ah);
 extern int ath5k_hw_phy_disable(struct ath5k_hw *ah);
 /* TX power setup */
 extern int ath5k_hw_txpower(struct ath5k_hw *ah, struct ieee80211_channel *channel, u8 ee_mode, u8 txpower);
-extern int ath5k_hw_set_txpower_limit(struct ath5k_hw *ah, u8 ee_mode, u8 txpower);
+extern int ath5k_hw_set_txpower_limit(struct ath5k_hw *ah, u8 txpower);
 
 /*
  * Functions used internaly

drivers/net/wireless/ath/ath5k/base.c

@@ -2747,12 +2747,21 @@ static int
 ath5k_config(struct ieee80211_hw *hw, u32 changed)
 {
 	struct ath5k_softc *sc = hw->priv;
+	struct ath5k_hw *ah = sc->ah;
 	struct ieee80211_conf *conf = &hw->conf;
 	int ret;
 
 	mutex_lock(&sc->lock);
 
-	sc->power_level = conf->power_level;
+	sc->bintval = conf->beacon_int;
+
+	if ((changed & IEEE80211_CONF_CHANGE_POWER) &&
+	(sc->power_level != conf->power_level)) {
+		sc->power_level = conf->power_level;
+
+		/* Half dB steps */
+		ath5k_hw_set_txpower_limit(ah, (conf->power_level * 2));
+	}
 
 	ret = ath5k_chan_set(sc, conf->channel);
 

drivers/net/wireless/ath/ath5k/phy.c

@@ -168,9 +168,6 @@ int ath5k_hw_rfgain_opt_init(struct ath5k_hw *ah)
  * tx power and a Peak to Average Power Detector (PAPD) will try
  * to measure the gain.
  *
- * TODO: Use propper tx power setting for the probe packet so
- * that we don't observe a serious power drop on the receiver
- *
  * XXX:  How about forcing a tx packet (bypassing PCU arbitrator etc)
  * just after we enable the probe so that we don't mess with
  * standard traffic ? Maybe it's time to use sw interrupts and
@@ -186,7 +183,7 @@ static void ath5k_hw_request_rfgain_probe(struct ath5k_hw *ah)
 
 	/* Send the packet with 2dB below max power as
 	 * patent doc suggest */
-	ath5k_hw_reg_write(ah, AR5K_REG_SM(ah->ah_txpower.txp_max_pwr - 4,
+	ath5k_hw_reg_write(ah, AR5K_REG_SM(ah->ah_txpower.txp_ofdm - 4,
 			AR5K_PHY_PAPD_PROBE_TXPOWER) |
 			AR5K_PHY_PAPD_PROBE_TX_NEXT, AR5K_PHY_PAPD_PROBE);
 
@@ -2482,8 +2479,19 @@ ath5k_setup_rate_powertable(struct ath5k_hw *ah, u16 max_pwr,
 		for (i = 8; i <= 15; i++)
 			rates[i] -= ah->ah_txpower.txp_cck_ofdm_gainf_delta;
 
-	ah->ah_txpower.txp_min_pwr = rates[7];
-	ah->ah_txpower.txp_max_pwr = rates[0];
+	/* Now that we have all rates setup use table offset to
+	 * match the power range set by user with the power indices
+	 * on PCDAC/PDADC table */
+	for (i = 0; i < 16; i++) {
+		rates[i] += ah->ah_txpower.txp_offset;
+		/* Don't get out of bounds */
+		if (rates[i] > 63)
+			rates[i] = 63;
+	}
+
+	/* Min/max in 0.25dB units */
+	ah->ah_txpower.txp_min_pwr = 2 * rates[7];
+	ah->ah_txpower.txp_max_pwr = 2 * rates[0];
 	ah->ah_txpower.txp_ofdm = rates[7];
 }
 
@@ -2591,16 +2599,37 @@ ath5k_hw_txpower(struct ath5k_hw *ah, struct ieee80211_channel *channel,
 	return 0;
 }
 
-int ath5k_hw_set_txpower_limit(struct ath5k_hw *ah, u8 mode, u8 txpower)
+int ath5k_hw_set_txpower_limit(struct ath5k_hw *ah, u8 txpower)
 {
 	/*Just a try M.F.*/
 	struct ieee80211_channel *channel = &ah->ah_current_channel;
+	u8 ee_mode;
 
 	ATH5K_TRACE(ah->ah_sc);
+
+	switch (channel->hw_value & CHANNEL_MODES) {
+	case CHANNEL_A:
+	case CHANNEL_T:
+	case CHANNEL_XR:
+		ee_mode = AR5K_EEPROM_MODE_11A;
+		break;
+	case CHANNEL_G:
+	case CHANNEL_TG:
+		ee_mode = AR5K_EEPROM_MODE_11G;
+		break;
+	case CHANNEL_B:
+		ee_mode = AR5K_EEPROM_MODE_11B;
+		break;
+	default:
+		ATH5K_ERR(ah->ah_sc,
+			"invalid channel: %d\n", channel->center_freq);
+		return -EINVAL;
+	}
+
 	ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_TXPOWER,
 		"changing txpower to %d\n", txpower);
 
-	return ath5k_hw_txpower(ah, channel, mode, txpower);
+	return ath5k_hw_txpower(ah, channel, ee_mode, txpower);
 }
 
 #undef _ATH5K_PHY

drivers/net/wireless/ath/ath5k/reset.c

@@ -1000,7 +1000,7 @@ int ath5k_hw_reset(struct ath5k_hw *ah, enum nl80211_iftype op_mode,
 		 * Set TX power (FIXME)
 		 */
 		ret = ath5k_hw_txpower(ah, channel, ee_mode,
-					AR5K_TUNE_DEFAULT_TXPOWER);
+					ah->ah_txpower.txp_max_pwr / 2);
 		if (ret)
 			return ret;