p54: 32-bit tsf timestamps

tcpdump:
02:15:42.874518 61112184us tsft 48.0 Mb/s 2437 MHz (0x0480) antenna 1 [0x0000000e] CF +QoS Data IV
02:15:42.874557 >>>4356079526us<<< tsft 24.0 Mb/s 2437 MHz (0x0480) antenna 1 [0x0000000e] Acknowledgment
02:15:42.976844 61214513us tsft 1.0 Mb/s 2437 MHz (0x0480) antenna 0 [0x0000000e] Beacon

as one can see on the huge jump, it's very plausible that firmware does not report the
full 64-bit mac time, just the lower 32bit and some kinds of flags...
Therefore if we want a useful timestamp we have to emulate the high bits.

Signed-off-by: Christian Lamparter <chunkeey@web.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 14 insertions, 2 deletions

diff --git a/drivers/net/wireless/p54/p54.h b/drivers/net/wireless/p54/p54.h
index 98d4f8e7d84d..36b8e584c6cf 100644
--- a/drivers/net/wireless/p54/p54.h
+++ b/drivers/net/wireless/p54/p54.h
@@ -87,6 +87,8 @@ struct p54_common {
         void *cached_vdcf;
         unsigned int fw_var;
         unsigned int fw_interface;
+        u32 tsf_low32;
+        u32 tsf_high32;
         struct ieee80211_tx_queue_stats tx_stats[8];
         void *eeprom;
         struct completion eeprom_comp;
diff --git a/drivers/net/wireless/p54/p54common.c b/drivers/net/wireless/p54/p54common.c
index f96f7c7e6af5..526d3a282b7a 100644
--- a/drivers/net/wireless/p54/p54common.c
+++ b/drivers/net/wireless/p54/p54common.c
@@ -426,10 +426,12 @@ EXPORT_SYMBOL_GPL(p54_parse_eeprom);
 
 static int p54_rx_data(struct ieee80211_hw *dev, struct sk_buff *skb)
 {
+        struct p54_common *priv = dev->priv;
         struct p54_rx_hdr *hdr = (struct p54_rx_hdr *) skb->data;
         struct ieee80211_rx_status rx_status = {0};
         u16 freq = le16_to_cpu(hdr->freq);
         size_t header_len = sizeof(*hdr);
+        u32 tsf32;
 
         rx_status.signal = hdr->rssi;
         /* XX correct? */
@@ -438,7 +440,13 @@ static int p54_rx_data(struct ieee80211_hw *dev, struct sk_buff *skb)
         rx_status.freq = freq;
         rx_status.band = IEEE80211_BAND_2GHZ;
         rx_status.antenna = hdr->antenna;
-        rx_status.mactime = le64_to_cpu(hdr->timestamp);
+
+        tsf32 = le32_to_cpu(hdr->tsf32);
+        if (tsf32 < priv->tsf_low32)
+                priv->tsf_high32++;
+        rx_status.mactime = ((u64)priv->tsf_high32) << 32 | tsf32;
+        priv->tsf_low32 = tsf32;
+
         rx_status.flag |= RX_FLAG_TSFT;
 
         if (hdr->magic & cpu_to_le16(0x4000))
@@ -1037,6 +1045,7 @@ static void p54_stop(struct ieee80211_hw *dev)
         while ((skb = skb_dequeue(&priv->tx_queue)))
                 kfree_skb(skb);
         priv->stop(dev);
+        priv->tsf_high32 = priv->tsf_low32 = 0;
         priv->mode = IEEE80211_IF_TYPE_INVALID;
 }
 
diff --git a/drivers/net/wireless/p54/p54common.h b/drivers/net/wireless/p54/p54common.h
index 73a9a2c923dd..976cbf9689b5 100644
--- a/drivers/net/wireless/p54/p54common.h
+++ b/drivers/net/wireless/p54/p54common.h
@@ -185,7 +185,8 @@ struct p54_rx_hdr {
         u8 rssi;
         u8 quality;
         u16 unknown2;
-        __le64 timestamp;
+        __le32 tsf32;
+        __le32 unalloc0;
         u8 align[0];
 } __attribute__ ((packed));