xref: /linux/net/dsa/dsa.c (revision 995231c820e3bd3633cb38bf4ea6f2541e1da331)
1 /*
2  * net/dsa/dsa.c - Hardware switch handling
3  * Copyright (c) 2008-2009 Marvell Semiconductor
4  * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11 
12 #include <linux/device.h>
13 #include <linux/list.h>
14 #include <linux/platform_device.h>
15 #include <linux/slab.h>
16 #include <linux/module.h>
17 #include <linux/notifier.h>
18 #include <linux/of.h>
19 #include <linux/of_mdio.h>
20 #include <linux/of_platform.h>
21 #include <linux/of_net.h>
22 #include <linux/of_gpio.h>
23 #include <linux/netdevice.h>
24 #include <linux/sysfs.h>
25 #include <linux/phy_fixed.h>
26 #include <linux/gpio/consumer.h>
27 #include <linux/etherdevice.h>
28 
29 #include "dsa_priv.h"
30 
31 static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
32 					    struct net_device *dev)
33 {
34 	/* Just return the original SKB */
35 	return skb;
36 }
37 
38 static const struct dsa_device_ops none_ops = {
39 	.xmit	= dsa_slave_notag_xmit,
40 	.rcv	= NULL,
41 };
42 
43 const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = {
44 #ifdef CONFIG_NET_DSA_TAG_BRCM
45 	[DSA_TAG_PROTO_BRCM] = &brcm_netdev_ops,
46 #endif
47 #ifdef CONFIG_NET_DSA_TAG_DSA
48 	[DSA_TAG_PROTO_DSA] = &dsa_netdev_ops,
49 #endif
50 #ifdef CONFIG_NET_DSA_TAG_EDSA
51 	[DSA_TAG_PROTO_EDSA] = &edsa_netdev_ops,
52 #endif
53 #ifdef CONFIG_NET_DSA_TAG_KSZ
54 	[DSA_TAG_PROTO_KSZ] = &ksz_netdev_ops,
55 #endif
56 #ifdef CONFIG_NET_DSA_TAG_LAN9303
57 	[DSA_TAG_PROTO_LAN9303] = &lan9303_netdev_ops,
58 #endif
59 #ifdef CONFIG_NET_DSA_TAG_MTK
60 	[DSA_TAG_PROTO_MTK] = &mtk_netdev_ops,
61 #endif
62 #ifdef CONFIG_NET_DSA_TAG_QCA
63 	[DSA_TAG_PROTO_QCA] = &qca_netdev_ops,
64 #endif
65 #ifdef CONFIG_NET_DSA_TAG_TRAILER
66 	[DSA_TAG_PROTO_TRAILER] = &trailer_netdev_ops,
67 #endif
68 	[DSA_TAG_PROTO_NONE] = &none_ops,
69 };
70 
71 const struct dsa_device_ops *dsa_resolve_tag_protocol(int tag_protocol)
72 {
73 	const struct dsa_device_ops *ops;
74 
75 	if (tag_protocol >= DSA_TAG_LAST)
76 		return ERR_PTR(-EINVAL);
77 	ops = dsa_device_ops[tag_protocol];
78 
79 	if (!ops)
80 		return ERR_PTR(-ENOPROTOOPT);
81 
82 	return ops;
83 }
84 
85 static int dev_is_class(struct device *dev, void *class)
86 {
87 	if (dev->class != NULL && !strcmp(dev->class->name, class))
88 		return 1;
89 
90 	return 0;
91 }
92 
93 static struct device *dev_find_class(struct device *parent, char *class)
94 {
95 	if (dev_is_class(parent, class)) {
96 		get_device(parent);
97 		return parent;
98 	}
99 
100 	return device_find_child(parent, class, dev_is_class);
101 }
102 
103 struct net_device *dsa_dev_to_net_device(struct device *dev)
104 {
105 	struct device *d;
106 
107 	d = dev_find_class(dev, "net");
108 	if (d != NULL) {
109 		struct net_device *nd;
110 
111 		nd = to_net_dev(d);
112 		dev_hold(nd);
113 		put_device(d);
114 
115 		return nd;
116 	}
117 
118 	return NULL;
119 }
120 EXPORT_SYMBOL_GPL(dsa_dev_to_net_device);
121 
122 static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
123 			  struct packet_type *pt, struct net_device *unused)
124 {
125 	struct dsa_port *cpu_dp = dev->dsa_ptr;
126 	struct sk_buff *nskb = NULL;
127 	struct pcpu_sw_netstats *s;
128 	struct dsa_slave_priv *p;
129 
130 	if (unlikely(!cpu_dp)) {
131 		kfree_skb(skb);
132 		return 0;
133 	}
134 
135 	skb = skb_unshare(skb, GFP_ATOMIC);
136 	if (!skb)
137 		return 0;
138 
139 	nskb = cpu_dp->rcv(skb, dev, pt);
140 	if (!nskb) {
141 		kfree_skb(skb);
142 		return 0;
143 	}
144 
145 	skb = nskb;
146 	p = netdev_priv(skb->dev);
147 	skb_push(skb, ETH_HLEN);
148 	skb->pkt_type = PACKET_HOST;
149 	skb->protocol = eth_type_trans(skb, skb->dev);
150 
151 	s = this_cpu_ptr(p->stats64);
152 	u64_stats_update_begin(&s->syncp);
153 	s->rx_packets++;
154 	s->rx_bytes += skb->len;
155 	u64_stats_update_end(&s->syncp);
156 
157 	netif_receive_skb(skb);
158 
159 	return 0;
160 }
161 
162 #ifdef CONFIG_PM_SLEEP
163 static bool dsa_is_port_initialized(struct dsa_switch *ds, int p)
164 {
165 	return dsa_is_user_port(ds, p) && ds->ports[p].slave;
166 }
167 
168 int dsa_switch_suspend(struct dsa_switch *ds)
169 {
170 	int i, ret = 0;
171 
172 	/* Suspend slave network devices */
173 	for (i = 0; i < ds->num_ports; i++) {
174 		if (!dsa_is_port_initialized(ds, i))
175 			continue;
176 
177 		ret = dsa_slave_suspend(ds->ports[i].slave);
178 		if (ret)
179 			return ret;
180 	}
181 
182 	if (ds->ops->suspend)
183 		ret = ds->ops->suspend(ds);
184 
185 	return ret;
186 }
187 EXPORT_SYMBOL_GPL(dsa_switch_suspend);
188 
189 int dsa_switch_resume(struct dsa_switch *ds)
190 {
191 	int i, ret = 0;
192 
193 	if (ds->ops->resume)
194 		ret = ds->ops->resume(ds);
195 
196 	if (ret)
197 		return ret;
198 
199 	/* Resume slave network devices */
200 	for (i = 0; i < ds->num_ports; i++) {
201 		if (!dsa_is_port_initialized(ds, i))
202 			continue;
203 
204 		ret = dsa_slave_resume(ds->ports[i].slave);
205 		if (ret)
206 			return ret;
207 	}
208 
209 	return 0;
210 }
211 EXPORT_SYMBOL_GPL(dsa_switch_resume);
212 #endif
213 
214 static struct packet_type dsa_pack_type __read_mostly = {
215 	.type	= cpu_to_be16(ETH_P_XDSA),
216 	.func	= dsa_switch_rcv,
217 };
218 
219 static struct workqueue_struct *dsa_owq;
220 
221 bool dsa_schedule_work(struct work_struct *work)
222 {
223 	return queue_work(dsa_owq, work);
224 }
225 
226 static ATOMIC_NOTIFIER_HEAD(dsa_notif_chain);
227 
228 int register_dsa_notifier(struct notifier_block *nb)
229 {
230 	return atomic_notifier_chain_register(&dsa_notif_chain, nb);
231 }
232 EXPORT_SYMBOL_GPL(register_dsa_notifier);
233 
234 int unregister_dsa_notifier(struct notifier_block *nb)
235 {
236 	return atomic_notifier_chain_unregister(&dsa_notif_chain, nb);
237 }
238 EXPORT_SYMBOL_GPL(unregister_dsa_notifier);
239 
240 int call_dsa_notifiers(unsigned long val, struct net_device *dev,
241 		       struct dsa_notifier_info *info)
242 {
243 	info->dev = dev;
244 	return atomic_notifier_call_chain(&dsa_notif_chain, val, info);
245 }
246 EXPORT_SYMBOL_GPL(call_dsa_notifiers);
247 
248 static int __init dsa_init_module(void)
249 {
250 	int rc;
251 
252 	dsa_owq = alloc_ordered_workqueue("dsa_ordered",
253 					  WQ_MEM_RECLAIM);
254 	if (!dsa_owq)
255 		return -ENOMEM;
256 
257 	rc = dsa_slave_register_notifier();
258 	if (rc)
259 		return rc;
260 
261 	rc = dsa_legacy_register();
262 	if (rc)
263 		return rc;
264 
265 	dev_add_pack(&dsa_pack_type);
266 
267 	return 0;
268 }
269 module_init(dsa_init_module);
270 
271 static void __exit dsa_cleanup_module(void)
272 {
273 	dsa_slave_unregister_notifier();
274 	dev_remove_pack(&dsa_pack_type);
275 	dsa_legacy_unregister();
276 	destroy_workqueue(dsa_owq);
277 }
278 module_exit(dsa_cleanup_module);
279 
280 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
281 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
282 MODULE_LICENSE("GPL");
283 MODULE_ALIAS("platform:dsa");
284