p54: parse output power table

For the upcoming tpc changes, the driver needs
to provide sensible max output values for each
supported channel.

And while the eeprom always had a output_limit
table, which defines the upper limit for each
frequency and modulation, it was never really
useful for anything... until now.

Note: For anyone wondering about what your card
is calibrated for: check "iw list".
	* 2412 MHz [1] (18.0 dBm)
	* 2437 MHz [6] (19.0 dBm)
	[...]
	* 5180 MHz [36] (18.0 dBm)
	* 5260 MHz [52] (17.0 dBm) (radar detection)
	* 5680 MHz [136] (19.0 dBm) (radar detection)
(for a Dell Wireless 1450 USB Adapter)
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/p54/eeprom.c

@@ -76,6 +76,7 @@ struct p54_channel_entry {
 	u16 freq;
 	u16 data;
 	int index;
+	int max_power;
 	enum ieee80211_band band;
 };
 
@@ -173,6 +174,7 @@ static int p54_generate_band(struct ieee80211_hw *dev,
 	for (i = 0, j = 0; (j < list->band_channel_num[band]) &&
 			   (i < list->entries); i++) {
 		struct p54_channel_entry *chan = &list->channels[i];
+		struct ieee80211_channel *dest = &tmp->channels[j];
 
 		if (chan->band != band)
 			continue;
@@ -190,14 +192,15 @@ static int p54_generate_band(struct ieee80211_hw *dev,
 			continue;
 		}
 
-		tmp->channels[j].band = chan->band;
-		tmp->channels[j].center_freq = chan->freq;
+		dest->band = chan->band;
+		dest->center_freq = chan->freq;
+		dest->max_power = chan->max_power;
 		priv->survey[*chan_num].channel = &tmp->channels[j];
 		priv->survey[*chan_num].filled = SURVEY_INFO_NOISE_DBM |
 			SURVEY_INFO_CHANNEL_TIME |
 			SURVEY_INFO_CHANNEL_TIME_BUSY |
 			SURVEY_INFO_CHANNEL_TIME_TX;
-		tmp->channels[j].hw_value = (*chan_num);
+		dest->hw_value = (*chan_num);
 		j++;
 		(*chan_num)++;
 	}
@@ -229,10 +232,11 @@ static int p54_generate_band(struct ieee80211_hw *dev,
 	return ret;
 }
 
-static void p54_update_channel_param(struct p54_channel_list *list,
+static struct p54_channel_entry *p54_update_channel_param(struct p54_channel_list *list,
 							  u16 freq, u16 data)
 {
-	int band, i;
+	int i;
+	struct p54_channel_entry *entry = NULL;
 
 	/*
 	 * usually all lists in the eeprom are mostly sorted.
@@ -241,30 +245,74 @@ static void p54_update_channel_param(struct p54_channel_list *list,
 	 */
 	for (i = list->entries; i >= 0; i--) {
 		if (freq == list->channels[i].freq) {
-			list->channels[i].data |= data;
+			entry = &list->channels[i];
 			break;
 		}
 	}
 
 	if ((i < 0) && (list->entries < list->max_entries)) {
 		/* entry does not exist yet. Initialize a new one. */
-		band = p54_get_band_from_freq(freq);
+		int band = p54_get_band_from_freq(freq);
 
 		/*
 		 * filter out frequencies which don't belong into
 		 * any supported band.
 		 */
-		if (band < 0)
-			return ;
-
+		if (band >= 0) {
 			i = list->entries++;
 			list->band_channel_num[band]++;
 
-		list->channels[i].freq = freq;
-		list->channels[i].data = data;
-		list->channels[i].band = band;
-		list->channels[i].index = ieee80211_frequency_to_channel(freq);
-		/* TODO: parse output_limit and fill max_power */
+			entry = &list->channels[i];
+			entry->freq = freq;
+			entry->band = band;
+			entry->index = ieee80211_frequency_to_channel(freq);
+			entry->max_power = 0;
+			entry->data = 0;
+		}
+	}
+
+	if (entry)
+		entry->data |= data;
+
+	return entry;
+}
+
+static int p54_get_maxpower(struct p54_common *priv, void *data)
+{
+	switch (priv->rxhw & PDR_SYNTH_FRONTEND_MASK) {
+	case PDR_SYNTH_FRONTEND_LONGBOW: {
+		struct pda_channel_output_limit_longbow *pda = data;
+		int j;
+		u16 rawpower = 0;
+		pda = data;
+		for (j = 0; j < ARRAY_SIZE(pda->point); j++) {
+			struct pda_channel_output_limit_point_longbow *point =
+				&pda->point[j];
+			rawpower = max(rawpower, le16_to_cpu(point->val_qpsk));
+			rawpower = max(rawpower, le16_to_cpu(point->val_bpsk));
+			rawpower = max(rawpower, le16_to_cpu(point->val_16qam));
+			rawpower = max(rawpower, le16_to_cpu(point->val_64qam));
+		}
+		/* longbow seems to use 1/16 dBm units */
+		return rawpower / 16;
+		}
+
+	case PDR_SYNTH_FRONTEND_DUETTE3:
+	case PDR_SYNTH_FRONTEND_DUETTE2:
+	case PDR_SYNTH_FRONTEND_FRISBEE:
+	case PDR_SYNTH_FRONTEND_XBOW: {
+		struct pda_channel_output_limit *pda = data;
+		u8 rawpower = 0;
+		rawpower = max(rawpower, pda->val_qpsk);
+		rawpower = max(rawpower, pda->val_bpsk);
+		rawpower = max(rawpower, pda->val_16qam);
+		rawpower = max(rawpower, pda->val_64qam);
+		/* raw values are in 1/4 dBm units */
+		return rawpower / 4;
+		}
+
+	default:
+		return 20;
 	}
 }
 
@@ -315,12 +363,19 @@ static int p54_generate_channel_lists(struct ieee80211_hw *dev)
 		}
 
 		if (i < priv->output_limit->entries) {
-			freq = le16_to_cpup((__le16 *) (i *
+			struct p54_channel_entry *tmp;
+
+			void *data = (void *) ((unsigned long) i *
 				priv->output_limit->entry_size +
 				priv->output_limit->offset +
-					    priv->output_limit->data));
+				priv->output_limit->data);
 
-			p54_update_channel_param(list, freq, CHAN_HAS_LIMIT);
+			freq = le16_to_cpup((__le16 *) data);
+			tmp = p54_update_channel_param(list, freq,
+						       CHAN_HAS_LIMIT);
+			if (tmp) {
+				tmp->max_power = p54_get_maxpower(priv, data);
+			}
 		}
 
 		if (i < priv->curve_data->entries) {
@@ -834,11 +889,12 @@ int p54_parse_eeprom(struct ieee80211_hw *dev, void *eeprom, int len)
 		goto err;
 	}
 
+	priv->rxhw = synth & PDR_SYNTH_FRONTEND_MASK;
+
 	err = p54_generate_channel_lists(dev);
 	if (err)
 		goto err;
 
-	priv->rxhw = synth & PDR_SYNTH_FRONTEND_MASK;
 	if (priv->rxhw == PDR_SYNTH_FRONTEND_XBOW)
 		p54_init_xbow_synth(priv);
 	if (!(synth & PDR_SYNTH_24_GHZ_DISABLED))

drivers/net/wireless/p54/eeprom.h

@@ -57,6 +57,18 @@ struct pda_channel_output_limit {
 	u8 rate_set_size;
 } __packed;
 
+struct pda_channel_output_limit_point_longbow {
+	__le16 val_bpsk;
+	__le16 val_qpsk;
+	__le16 val_16qam;
+	__le16 val_64qam;
+} __packed;
+
+struct pda_channel_output_limit_longbow {
+	__le16 freq;
+	struct pda_channel_output_limit_point_longbow point[3];
+} __packed;
+
 struct pda_pa_curve_data_sample_rev0 {
 	u8 rf_power;
 	u8 pa_detector;