mac802154: RX data path
Main RX data path implementation between physical and mac layers.
Signed-off-by: Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mac802154/rx.c b/net/mac802154/rx.c
new file mode 100644
index 0000000..d15738f
--- /dev/null
+++ b/net/mac802154/rx.c
@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2007-2012 Siemens AG
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Written by:
+ * Pavel Smolenskiy <pavel.smolenskiy@gmail.com>
+ * Maxim Gorbachyov <maxim.gorbachev@siemens.com>
+ * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
+ * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/workqueue.h>
+#include <linux/netdevice.h>
+#include <linux/crc-ccitt.h>
+
+#include <net/mac802154.h>
+#include <net/ieee802154_netdev.h>
+
+#include "mac802154.h"
+
+/* The IEEE 802.15.4 standard defines 4 MAC packet types:
+ * - beacon frame
+ * - MAC command frame
+ * - acknowledgement frame
+ * - data frame
+ *
+ * and only the data frame should be pushed to the upper layers, other types
+ * are just internal MAC layer management information. So only data packets
+ * are going to be sent to the networking queue, all other will be processed
+ * right here by using the device workqueue.
+ */
+struct rx_work {
+ struct sk_buff *skb;
+ struct work_struct work;
+ struct ieee802154_dev *dev;
+ u8 lqi;
+};
+
+static void
+mac802154_subif_rx(struct ieee802154_dev *hw, struct sk_buff *skb, u8 lqi)
+{
+ struct mac802154_priv *priv = mac802154_to_priv(hw);
+
+ mac_cb(skb)->lqi = lqi;
+ skb->protocol = htons(ETH_P_IEEE802154);
+ skb_reset_mac_header(skb);
+
+ BUILD_BUG_ON(sizeof(struct ieee802154_mac_cb) > sizeof(skb->cb));
+
+ if (!(priv->hw.flags & IEEE802154_HW_OMIT_CKSUM)) {
+ u16 crc;
+
+ if (skb->len < 2) {
+ pr_debug("got invalid frame\n");
+ goto out;
+ }
+ crc = crc_ccitt(0, skb->data, skb->len);
+ if (crc) {
+ pr_debug("CRC mismatch\n");
+ goto out;
+ }
+ skb_trim(skb, skb->len - 2); /* CRC */
+ }
+
+out:
+ dev_kfree_skb(skb);
+ return;
+}
+
+static void mac802154_rx_worker(struct work_struct *work)
+{
+ struct rx_work *rw = container_of(work, struct rx_work, work);
+ struct sk_buff *skb = rw->skb;
+
+ mac802154_subif_rx(rw->dev, skb, rw->lqi);
+ kfree(rw);
+}
+
+void
+ieee802154_rx_irqsafe(struct ieee802154_dev *dev, struct sk_buff *skb, u8 lqi)
+{
+ struct mac802154_priv *priv = mac802154_to_priv(dev);
+ struct rx_work *work;
+
+ if (!skb)
+ return;
+
+ work = kzalloc(sizeof(struct rx_work), GFP_ATOMIC);
+ if (!work)
+ return;
+
+ INIT_WORK(&work->work, mac802154_rx_worker);
+ work->skb = skb;
+ work->dev = dev;
+ work->lqi = lqi;
+
+ queue_work(priv->dev_workqueue, &work->work);
+}
+EXPORT_SYMBOL(ieee802154_rx_irqsafe);