1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2020-21 Intel Corporation.
6 #include <linux/etherdevice.h>
7 #include <linux/if_arp.h>
8 #include <linux/if_link.h>
9 #include <linux/rtnetlink.h>
10 #include <linux/wwan.h>
12 #include "iosm_ipc_chnl_cfg.h"
13 #include "iosm_ipc_imem_ops.h"
14 #include "iosm_ipc_wwan.h"
16 #define IOSM_IP_TYPE_MASK 0xF0
17 #define IOSM_IP_TYPE_IPV4 0x40
18 #define IOSM_IP_TYPE_IPV6 0x60
20 #define IOSM_IF_ID_PAYLOAD 2
23 * struct iosm_netdev_priv - netdev WWAN driver specific private data
24 * @ipc_wwan: Pointer to iosm_wwan struct
25 * @netdev: Pointer to network interface device structure
26 * @if_id: Interface id for device.
27 * @ch_id: IPC channel number for which interface device is created.
29 struct iosm_netdev_priv {
30 struct iosm_wwan *ipc_wwan;
31 struct net_device *netdev;
37 * struct iosm_wwan - This structure contains information about WWAN root device
38 * and interface to the IPC layer.
39 * @ipc_imem: Pointer to imem data-struct
40 * @sub_netlist: List of active netdevs
41 * @dev: Pointer device structure
42 * @if_mutex: Mutex used for add and remove interface id
45 struct iosm_imem *ipc_imem;
46 struct iosm_netdev_priv __rcu *sub_netlist[IP_MUX_SESSION_END + 1];
48 struct mutex if_mutex; /* Mutex used for add and remove interface id */
51 /* Bring-up the wwan net link */
52 static int ipc_wwan_link_open(struct net_device *netdev)
54 struct iosm_netdev_priv *priv = wwan_netdev_drvpriv(netdev);
55 struct iosm_wwan *ipc_wwan = priv->ipc_wwan;
56 int if_id = priv->if_id;
59 if (if_id < IP_MUX_SESSION_START ||
60 if_id >= ARRAY_SIZE(ipc_wwan->sub_netlist))
63 mutex_lock(&ipc_wwan->if_mutex);
66 priv->ch_id = ipc_imem_sys_wwan_open(ipc_wwan->ipc_imem, if_id);
68 if (priv->ch_id < 0) {
69 dev_err(ipc_wwan->dev,
70 "cannot connect wwan0 & id %d to the IPC mem layer",
76 /* enable tx path, DL data may follow */
77 netif_start_queue(netdev);
79 dev_dbg(ipc_wwan->dev, "Channel id %d allocated to if_id %d",
80 priv->ch_id, priv->if_id);
84 mutex_unlock(&ipc_wwan->if_mutex);
88 /* Bring-down the wwan net link */
89 static int ipc_wwan_link_stop(struct net_device *netdev)
91 struct iosm_netdev_priv *priv = wwan_netdev_drvpriv(netdev);
93 netif_stop_queue(netdev);
95 mutex_lock(&priv->ipc_wwan->if_mutex);
96 ipc_imem_sys_wwan_close(priv->ipc_wwan->ipc_imem, priv->if_id,
99 mutex_unlock(&priv->ipc_wwan->if_mutex);
104 /* Transmit a packet */
105 static int ipc_wwan_link_transmit(struct sk_buff *skb,
106 struct net_device *netdev)
108 struct iosm_netdev_priv *priv = wwan_netdev_drvpriv(netdev);
109 struct iosm_wwan *ipc_wwan = priv->ipc_wwan;
110 int if_id = priv->if_id;
113 /* Interface IDs from 1 to 8 are for IP data
114 * & from 257 to 261 are for non-IP data
116 if (if_id < IP_MUX_SESSION_START ||
117 if_id >= ARRAY_SIZE(ipc_wwan->sub_netlist))
120 /* Send the SKB to device for transmission */
121 ret = ipc_imem_sys_wwan_transmit(ipc_wwan->ipc_imem,
122 if_id, priv->ch_id, skb);
124 /* Return code of zero is success */
127 } else if (ret == -EBUSY) {
128 ret = NETDEV_TX_BUSY;
129 dev_err(ipc_wwan->dev, "unable to push packets");
137 /* Log any skb drop */
139 dev_dbg(ipc_wwan->dev, "skb dropped. IF_ID: %d, ret: %d", if_id,
142 dev_kfree_skb_any(skb);
146 /* Ops structure for wwan net link */
147 static const struct net_device_ops ipc_inm_ops = {
148 .ndo_open = ipc_wwan_link_open,
149 .ndo_stop = ipc_wwan_link_stop,
150 .ndo_start_xmit = ipc_wwan_link_transmit,
153 /* Setup function for creating new net link */
154 static void ipc_wwan_setup(struct net_device *iosm_dev)
156 iosm_dev->header_ops = NULL;
157 iosm_dev->hard_header_len = 0;
158 iosm_dev->priv_flags |= IFF_NO_QUEUE;
160 iosm_dev->type = ARPHRD_NONE;
161 iosm_dev->min_mtu = ETH_MIN_MTU;
162 iosm_dev->max_mtu = ETH_MAX_MTU;
164 iosm_dev->flags = IFF_POINTOPOINT | IFF_NOARP;
166 iosm_dev->netdev_ops = &ipc_inm_ops;
169 /* Create new wwan net link */
170 static int ipc_wwan_newlink(void *ctxt, struct net_device *dev,
171 u32 if_id, struct netlink_ext_ack *extack)
173 struct iosm_wwan *ipc_wwan = ctxt;
174 struct iosm_netdev_priv *priv;
177 if (if_id < IP_MUX_SESSION_START ||
178 if_id >= ARRAY_SIZE(ipc_wwan->sub_netlist))
181 priv = wwan_netdev_drvpriv(dev);
184 priv->ipc_wwan = ipc_wwan;
186 mutex_lock(&ipc_wwan->if_mutex);
187 if (rcu_access_pointer(ipc_wwan->sub_netlist[if_id])) {
192 err = register_netdevice(dev);
196 rcu_assign_pointer(ipc_wwan->sub_netlist[if_id], priv);
197 mutex_unlock(&ipc_wwan->if_mutex);
199 netif_device_attach(dev);
204 mutex_unlock(&ipc_wwan->if_mutex);
208 static void ipc_wwan_dellink(void *ctxt, struct net_device *dev,
209 struct list_head *head)
211 struct iosm_netdev_priv *priv = wwan_netdev_drvpriv(dev);
212 struct iosm_wwan *ipc_wwan = ctxt;
213 int if_id = priv->if_id;
215 if (WARN_ON(if_id < IP_MUX_SESSION_START ||
216 if_id >= ARRAY_SIZE(ipc_wwan->sub_netlist)))
219 mutex_lock(&ipc_wwan->if_mutex);
221 if (WARN_ON(rcu_access_pointer(ipc_wwan->sub_netlist[if_id]) != priv))
224 RCU_INIT_POINTER(ipc_wwan->sub_netlist[if_id], NULL);
225 /* unregistering includes synchronize_net() */
226 unregister_netdevice(dev);
229 mutex_unlock(&ipc_wwan->if_mutex);
232 static const struct wwan_ops iosm_wwan_ops = {
233 .priv_size = sizeof(struct iosm_netdev_priv),
234 .setup = ipc_wwan_setup,
235 .newlink = ipc_wwan_newlink,
236 .dellink = ipc_wwan_dellink,
239 int ipc_wwan_receive(struct iosm_wwan *ipc_wwan, struct sk_buff *skb_arg,
242 struct sk_buff *skb = skb_arg;
243 struct net_device_stats *stats;
244 struct iosm_netdev_priv *priv;
247 if ((skb->data[0] & IOSM_IP_TYPE_MASK) == IOSM_IP_TYPE_IPV4)
248 skb->protocol = htons(ETH_P_IP);
249 else if ((skb->data[0] & IOSM_IP_TYPE_MASK) ==
251 skb->protocol = htons(ETH_P_IPV6);
253 skb->pkt_type = PACKET_HOST;
255 if (if_id < (IP_MUX_SESSION_START - 1) ||
256 if_id > (IP_MUX_SESSION_END - 1)) {
262 priv = rcu_dereference(ipc_wwan->sub_netlist[if_id]);
267 skb->dev = priv->netdev;
268 stats = &priv->netdev->stats;
270 stats->rx_bytes += skb->len;
281 void ipc_wwan_tx_flowctrl(struct iosm_wwan *ipc_wwan, int if_id, bool on)
283 struct net_device *netdev;
284 struct iosm_netdev_priv *priv;
288 priv = rcu_dereference(ipc_wwan->sub_netlist[if_id]);
294 netdev = priv->netdev;
296 is_tx_blk = netif_queue_stopped(netdev);
299 dev_dbg(ipc_wwan->dev, "session id[%d]: flowctrl enable",
302 if (on && !is_tx_blk)
303 netif_stop_queue(netdev);
304 else if (!on && is_tx_blk)
305 netif_wake_queue(netdev);
309 struct iosm_wwan *ipc_wwan_init(struct iosm_imem *ipc_imem, struct device *dev)
311 struct iosm_wwan *ipc_wwan;
313 ipc_wwan = kzalloc(sizeof(*ipc_wwan), GFP_KERNEL);
318 ipc_wwan->ipc_imem = ipc_imem;
320 /* WWAN core will create a netdev for the default IP MUX channel */
321 if (wwan_register_ops(ipc_wwan->dev, &iosm_wwan_ops, ipc_wwan,
322 IP_MUX_SESSION_DEFAULT)) {
327 mutex_init(&ipc_wwan->if_mutex);
332 void ipc_wwan_deinit(struct iosm_wwan *ipc_wwan)
334 /* This call will remove all child netdev(s) */
335 wwan_unregister_ops(ipc_wwan->dev);
337 mutex_destroy(&ipc_wwan->if_mutex);