usbus_cdc_ecm: Provide netdev integration

sys/usb/usbus/cdc/ecm/cdc_ecm_netdev.c

@@ -0,0 +1,199 @@
+/*
+ * Copyright (C) 2019 Koen Zandberg
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup usbus_cdc_ecm
+ * @{
+ * @file Netdev implementation for ethernet control model
+ *
+ * @author  Koen Zandberg <koen@bergzand.net>
+ * @}
+ */
+
+#include <string.h>
+
+#include "kernel_defines.h"
+#include "iolist.h"
+#include "luid.h"
+#include "mutex.h"
+#include "net/ethernet.h"
+#include "net/eui48.h"
+#include "net/netdev.h"
+#include "net/netdev/eth.h"
+#include "usb/usbus/cdc/ecm.h"
+
+#define ENABLE_DEBUG    (0)
+#include "debug.h"
+
+static const netdev_driver_t netdev_driver_cdcecm;
+
+static void _signal_rx_flush(usbus_cdcecm_device_t *cdcecm)
+{
+    usbus_event_post(cdcecm->usbus, &cdcecm->rx_flush);
+}
+
+static void _signal_tx_xmit(usbus_cdcecm_device_t *cdcecm)
+{
+    usbus_event_post(cdcecm->usbus, &cdcecm->tx_xmit);
+}
+
+static usbus_cdcecm_device_t *_netdev_to_cdcecm(netdev_t *netdev)
+{
+    return container_of(netdev, usbus_cdcecm_device_t, netdev);
+}
+
+void cdcecm_netdev_setup(usbus_cdcecm_device_t *cdcecm)
+{
+    cdcecm->netdev.driver = &netdev_driver_cdcecm;
+}
+
+static int _send(netdev_t *netdev, const iolist_t *iolist)
+{
+    assert(iolist);
+    usbus_cdcecm_device_t *cdcecm = _netdev_to_cdcecm(netdev);
+    uint8_t *buf = cdcecm->ep_in->ep->buf;
+    const iolist_t *iolist_start = iolist;
+    size_t len = iolist_size(iolist);
+    DEBUG("CDC_ECM_netdev: sending %u bytes\n", len);
+    /* load packet data into FIFO */
+    size_t iol_offset = 0;
+    size_t usb_offset = 0;
+    size_t usb_remain = cdcecm->ep_in->ep->len;
+    DEBUG("CDC_ECM_netdev: cur iol: %d\n", iolist->iol_len);
+    while (len) {
+        mutex_lock(&cdcecm->out_lock);
+        if (iolist->iol_len - iol_offset > usb_remain) {
+            /* Only part of the iolist can be copied, usb_remain bytes */
+            memcpy(buf + usb_offset, (uint8_t *)iolist->iol_base + iol_offset,
+                   usb_remain);
+
+            usb_offset =  cdcecm->ep_in->maxpacketsize;
+            len -= usb_remain;
+            iol_offset += usb_remain;
+            usb_remain = 0;
+        }
+        else {
+            size_t bytes_copied = iolist->iol_len - iol_offset;
+            /* Full iolist can be copied */
+            memcpy(buf + usb_offset, (uint8_t *)iolist->iol_base + iol_offset,
+                   bytes_copied);
+            len -= bytes_copied;
+            usb_offset += bytes_copied;
+            usb_remain -= bytes_copied;
+            iol_offset = iolist->iol_len;
+        }
+        if (iol_offset == iolist->iol_len) {
+            /* Current iolist exhausted */
+            iolist = iolist->iol_next;
+            if (iolist) {
+                DEBUG("CDC_ECM: cur iol: %d\n", iolist->iol_len);
+            }
+            iol_offset = 0;
+        }
+        if (usb_remain == 0 || !len) {
+            cdcecm->tx_len = usb_offset;
+            /* USB frame full or last frame, flush! */
+
+            DEBUG("CDC_ECM_NETDEV: triggering xmit with len %d\n",
+                  cdcecm->tx_len);
+            _signal_tx_xmit(cdcecm);
+            usb_remain = cdcecm->ep_in->maxpacketsize;
+            usb_offset = 0;
+        }
+        else {
+            mutex_unlock(&cdcecm->out_lock);
+        }
+    }
+    /* Zero length USB packet required */
+    if ((iolist_size(iolist_start) % cdcecm->ep_in->maxpacketsize) == 0) {
+        mutex_lock(&cdcecm->out_lock);
+        DEBUG("CDC ECM netdev: Zero length USB packet required\n");
+        cdcecm->tx_len = 0;
+        _signal_tx_xmit(cdcecm);
+    }
+    return len;
+}
+
+static int _recv(netdev_t *netdev, void *buf, size_t max_len, void *info)
+{
+    usbus_cdcecm_device_t *cdcecm = _netdev_to_cdcecm(netdev);
+
+    (void)info;
+    if (max_len == 0 && buf == NULL) {
+        return cdcecm->len;
+    }
+    if (max_len && buf == NULL) {
+        _signal_rx_flush(cdcecm);
+        return cdcecm->len;
+    }
+    memcpy(buf, cdcecm->in_buf, max_len);
+    _signal_rx_flush(cdcecm);
+    return max_len;
+}
+
+static int _init(netdev_t *netdev)
+{
+    usbus_cdcecm_device_t *cdcecm = _netdev_to_cdcecm(netdev);
+
+    luid_get(cdcecm->mac_netdev, ETHERNET_ADDR_LEN);
+    eui48_set_local((eui48_t*)cdcecm->mac_netdev);
+    eui48_clear_group((eui48_t*)cdcecm->mac_netdev);
+    return 0;
+}
+
+static int _get(netdev_t *netdev, netopt_t opt, void *value, size_t max_len)
+{
+    usbus_cdcecm_device_t *cdcecm = _netdev_to_cdcecm(netdev);
+
+    (void)max_len;
+
+    switch (opt) {
+        case NETOPT_ADDRESS:
+            assert(max_len >= ETHERNET_ADDR_LEN);
+            memcpy(value, cdcecm->mac_netdev, ETHERNET_ADDR_LEN);
+            return ETHERNET_ADDR_LEN;
+        default:
+            return netdev_eth_get(netdev, opt, value, max_len);
+    }
+}
+
+static int _set(netdev_t *netdev, netopt_t opt, const void *value,
+                size_t value_len)
+{
+    usbus_cdcecm_device_t *cdcecm = _netdev_to_cdcecm(netdev);
+
+    (void)cdcecm;
+
+    switch (opt) {
+        case NETOPT_ADDRESS:
+            assert(value_len == ETHERNET_ADDR_LEN);
+            memcpy(cdcecm->mac_netdev, value, ETHERNET_ADDR_LEN);
+            return ETHERNET_ADDR_LEN;
+        default:
+            return netdev_eth_set(netdev, opt, value, value_len);
+    }
+}
+
+static void _isr(netdev_t *dev)
+{
+    usbus_cdcecm_device_t *cdcecm = _netdev_to_cdcecm(dev);
+
+    if (cdcecm->len) {
+        cdcecm->netdev.event_callback(&cdcecm->netdev,
+                                      NETDEV_EVENT_RX_COMPLETE);
+    }
+}
+
+static const netdev_driver_t netdev_driver_cdcecm = {
+    .send = _send,
+    .recv = _recv,
+    .init = _init,
+    .isr = _isr,
+    .get = _get,
+    .set = _set,
+};