rtl8180: add software-based support for IBSS mode

Device documentation suggests that hardware support for beaconing
is available.  But I implemented software-based beacon generation
as an experiment and it seems better to have that working now rather
than waiting for something better to materialize.

Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 80 insertions, 10 deletions

diff --git a/drivers/net/wireless/rtl818x/rtl8180.h b/drivers/net/wireless/rtl818x/rtl8180.h
index b92d678abc0c..4baf0cf0826f 100644
--- a/drivers/net/wireless/rtl818x/rtl8180.h
+++ b/drivers/net/wireless/rtl818x/rtl8180.h
@@ -55,6 +55,14 @@ struct rtl8180_tx_ring {
         struct sk_buff_head queue;
 };
 
+struct rtl8180_vif {
+        struct ieee80211_hw *dev;
+
+        /* beaconing */
+        struct delayed_work beacon_work;
+        bool enable_beacon;
+};
+
 struct rtl8180_priv {
         /* common between rtl818x drivers */
         struct rtl818x_csr __iomem *map;
diff --git a/drivers/net/wireless/rtl818x/rtl8180_dev.c b/drivers/net/wireless/rtl818x/rtl8180_dev.c
index 3a214d7507a5..cbdc5cfec90c 100644
--- a/drivers/net/wireless/rtl818x/rtl8180_dev.c
+++ b/drivers/net/wireless/rtl818x/rtl8180_dev.c
@@ -662,10 +662,59 @@ static void rtl8180_stop(struct ieee80211_hw *dev)
                 rtl8180_free_tx_ring(dev, i);
 }
 
+static u64 rtl8180_get_tsf(struct ieee80211_hw *dev)
+{
+        struct rtl8180_priv *priv = dev->priv;
+
+        return rtl818x_ioread32(priv, &priv->map->TSFT[0]) |
+               (u64)(rtl818x_ioread32(priv, &priv->map->TSFT[1])) << 32;
+}
+
+void rtl8180_beacon_work(struct work_struct *work)
+{
+        struct rtl8180_vif *vif_priv =
+                container_of(work, struct rtl8180_vif, beacon_work.work);
+        struct ieee80211_vif *vif =
+                container_of((void *)vif_priv, struct ieee80211_vif, drv_priv);
+        struct ieee80211_hw *dev = vif_priv->dev;
+        struct ieee80211_mgmt *mgmt;
+        struct sk_buff *skb;
+        int err = 0;
+
+        /* don't overflow the tx ring */
+        if (ieee80211_queue_stopped(dev, 0))
+                goto resched;
+
+        /* grab a fresh beacon */
+        skb = ieee80211_beacon_get(dev, vif);
+
+        /*
+         * update beacon timestamp w/ TSF value
+         * TODO: make hardware update beacon timestamp
+         */
+        mgmt = (struct ieee80211_mgmt *)skb->data;
+        mgmt->u.beacon.timestamp = cpu_to_le64(rtl8180_get_tsf(dev));
+
+        /* TODO: use actual beacon queue */
+        skb_set_queue_mapping(skb, 0);
+
+        err = rtl8180_tx(dev, skb);
+        WARN_ON(err);
+
+resched:
+        /*
+         * schedule next beacon
+         * TODO: use hardware support for beacon timing
+         */
+        schedule_delayed_work(&vif_priv->beacon_work,
+                        usecs_to_jiffies(1024 * vif->bss_conf.beacon_int));
+}
+
 static int rtl8180_add_interface(struct ieee80211_hw *dev,
                                  struct ieee80211_vif *vif)
 {
         struct rtl8180_priv *priv = dev->priv;
+        struct rtl8180_vif *vif_priv;
 
         /*
          * We only support one active interface at a time.
@@ -675,6 +724,7 @@ static int rtl8180_add_interface(struct ieee80211_hw *dev,
 
         switch (vif->type) {
         case NL80211_IFTYPE_STATION:
+        case NL80211_IFTYPE_ADHOC:
                 break;
         default:
                 return -EOPNOTSUPP;
@@ -682,6 +732,12 @@ static int rtl8180_add_interface(struct ieee80211_hw *dev,
 
         priv->vif = vif;
 
+        /* Initialize driver private area */
+        vif_priv = (struct rtl8180_vif *)&vif->drv_priv;
+        vif_priv->dev = dev;
+        INIT_DELAYED_WORK(&vif_priv->beacon_work, rtl8180_beacon_work);
+        vif_priv->enable_beacon = false;
+
         rtl818x_iowrite8(priv, &priv->map->EEPROM_CMD, RTL818X_EEPROM_CMD_CONFIG);
         rtl818x_iowrite32(priv, (__le32 __iomem *)&priv->map->MAC[0],
                           le32_to_cpu(*(__le32 *)vif->addr));
@@ -715,8 +771,11 @@ static void rtl8180_bss_info_changed(struct ieee80211_hw *dev,
                                      u32 changed)
 {
         struct rtl8180_priv *priv = dev->priv;
+        struct rtl8180_vif *vif_priv;
         int i;
 
+        vif_priv = (struct rtl8180_vif *)&vif->drv_priv;
+
         if (changed & BSS_CHANGED_BSSID) {
                 for (i = 0; i < ETH_ALEN; i++)
                         rtl818x_iowrite8(priv, &priv->map->BSSID[i],
@@ -731,7 +790,16 @@ static void rtl8180_bss_info_changed(struct ieee80211_hw *dev,
         }
 
         if (changed & BSS_CHANGED_ERP_SLOT && priv->rf->conf_erp)
-                priv->rf->conf_erp(dev, info);
+                priv->rf->conf_erp(dev, info);
+
+        if (changed & BSS_CHANGED_BEACON_ENABLED)
+                vif_priv->enable_beacon = info->enable_beacon;
+
+        if (changed & (BSS_CHANGED_BEACON_ENABLED | BSS_CHANGED_BEACON)) {
+                cancel_delayed_work_sync(&vif_priv->beacon_work);
+                if (vif_priv->enable_beacon)
+                        schedule_work(&vif_priv->beacon_work.work);
+        }
 }
 
 static u64 rtl8180_prepare_multicast(struct ieee80211_hw *dev, int mc_count,
@@ -772,14 +840,6 @@ static void rtl8180_configure_filter(struct ieee80211_hw *dev,
         rtl818x_iowrite32(priv, &priv->map->RX_CONF, priv->rx_conf);
 }
 
-static u64 rtl8180_get_tsf(struct ieee80211_hw *dev)
-{
-        struct rtl8180_priv *priv = dev->priv;
-
-        return rtl818x_ioread32(priv, &priv->map->TSFT[0]) |
-               (u64)(rtl818x_ioread32(priv, &priv->map->TSFT[1])) << 32;
-}
-
 static const struct ieee80211_ops rtl8180_ops = {
         .tx                     = rtl8180_tx,
         .start                  = rtl8180_start,
@@ -916,7 +976,9 @@ static int __devinit rtl8180_probe(struct pci_dev *pdev,
         dev->flags = IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING |
                      IEEE80211_HW_RX_INCLUDES_FCS |
                      IEEE80211_HW_SIGNAL_UNSPEC;
-        dev->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
+        dev->vif_data_size = sizeof(struct rtl8180_vif);
+        dev->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION) |
+                                        BIT(NL80211_IFTYPE_ADHOC);
         dev->queues = 1;
         dev->max_signal = 65;