mac802154: cfg: add suspend and resume callbacks

This patch introduces suspend and resume callbacks to mac802154. When
doing suspend we calling the stop driver callback which should stop the
receiving of frames. A transceiver should go into low-power mode then.
Calling resume will call the start driver callback, which starts receiving
again and allow to transmit frames.

This was tested only with the fakelb driver and a qemu vm by doing the
following commands:

echo "devices" > /sys/power/pm_test
echo "freeze" > /sys/power/state

while doing some high traffic between two fakelb phys.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/net/mac802154/cfg.c b/net/mac802154/cfg.c
index 44db861..f7ba51e 100644 (file)
--- a/net/mac802154/cfg.c
+++ b/net/mac802154/cfg.c
@@ -44,6 +44,49 @@ static void ieee802154_del_iface_deprecated(struct wpan_phy *wpan_phy,
        ieee802154_if_remove(sdata);
 }
 
+#ifdef CONFIG_PM
+static int ieee802154_suspend(struct wpan_phy *wpan_phy)
+{
+       struct ieee802154_local *local = wpan_phy_priv(wpan_phy);
+
+       if (!local->open_count)
+               goto suspend;
+
+       ieee802154_stop_queue(&local->hw);
+       synchronize_net();
+
+       /* stop hardware - this must stop RX */
+       ieee802154_stop_device(local);
+
+suspend:
+       local->suspended = true;
+       return 0;
+}
+
+static int ieee802154_resume(struct wpan_phy *wpan_phy)
+{
+       struct ieee802154_local *local = wpan_phy_priv(wpan_phy);
+       int ret;
+
+       /* nothing to do if HW shouldn't run */
+       if (!local->open_count)
+               goto wake_up;
+
+       /* restart hardware */
+       ret = drv_start(local);
+       if (ret)
+               return ret;
+
+wake_up:
+       ieee802154_wake_queue(&local->hw);
+       local->suspended = false;
+       return 0;
+}
+#else
+#define ieee802154_suspend NULL
+#define ieee802154_resume NULL
+#endif
+
 static int
 ieee802154_add_iface(struct wpan_phy *phy, const char *name,
                     unsigned char name_assign_type,
@@ -232,6 +275,8 @@ ieee802154_set_lbt_mode(struct wpan_phy *wpan_phy, struct wpan_dev *wpan_dev,
 const struct cfg802154_ops mac802154_config_ops = {
        .add_virtual_intf_deprecated = ieee802154_add_iface_deprecated,
        .del_virtual_intf_deprecated = ieee802154_del_iface_deprecated,
+       .suspend = ieee802154_suspend,
+       .resume = ieee802154_resume,
        .add_virtual_intf = ieee802154_add_iface,
        .del_virtual_intf = ieee802154_del_iface,
        .set_channel = ieee802154_set_channel,

diff --git a/net/mac802154/ieee802154_i.h b/net/mac802154/ieee802154_i.h
index 0407783..0054f39 100644 (file)
--- a/net/mac802154/ieee802154_i.h
+++ b/net/mac802154/ieee802154_i.h
@@ -56,6 +56,7 @@ struct ieee802154_local {
        struct hrtimer ifs_timer;
 
        bool started;
+       bool suspended;
 
        struct tasklet_struct tasklet;
        struct sk_buff_head skb_queue;

diff --git a/net/mac802154/rx.c b/net/mac802154/rx.c
index d93ad2d..5a258c1 100644 (file)
--- a/net/mac802154/rx.c
+++ b/net/mac802154/rx.c
@@ -253,6 +253,9 @@ void ieee802154_rx(struct ieee802154_hw *hw, struct sk_buff *skb)
 
        WARN_ON_ONCE(softirq_count() == 0);
 
+       if (local->suspended)
+               goto drop;
+
        /* TODO: When a transceiver omits the checksum here, we
         * add an own calculated one. This is currently an ugly
         * solution because the monitor needs a crc here.
@@ -273,8 +276,7 @@ void ieee802154_rx(struct ieee802154_hw *hw, struct sk_buff *skb)
                crc = crc_ccitt(0, skb->data, skb->len);
                if (crc) {
                        rcu_read_unlock();
-                       kfree_skb(skb);
-                       return;
+                       goto drop;
                }
        }
        /* remove crc */
@@ -283,6 +285,10 @@ void ieee802154_rx(struct ieee802154_hw *hw, struct sk_buff *skb)
        __ieee802154_rx_handle_packet(local, skb);
 
        rcu_read_unlock();
+
+       return;
+drop:
+       kfree_skb(skb);
 }
 EXPORT_SYMBOL(ieee802154_rx);