Linux 5.1-rc1
[linux/fpc-iii.git] / net / caif / caif_usb.c
blob1a082a946045e53f1617cc9a814bae5dcb9784e7
1 /*
2 * CAIF USB handler
3 * Copyright (C) ST-Ericsson AB 2011
4 * Author: Sjur Brendeland
5 * License terms: GNU General Public License (GPL) version 2
7 */
9 #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
11 #include <linux/module.h>
12 #include <linux/netdevice.h>
13 #include <linux/slab.h>
14 #include <linux/mii.h>
15 #include <linux/usb.h>
16 #include <linux/usb/usbnet.h>
17 #include <linux/etherdevice.h>
18 #include <net/netns/generic.h>
19 #include <net/caif/caif_dev.h>
20 #include <net/caif/caif_layer.h>
21 #include <net/caif/cfpkt.h>
22 #include <net/caif/cfcnfg.h>
24 MODULE_LICENSE("GPL");
26 #define CFUSB_PAD_DESCR_SZ 1 /* Alignment descriptor length */
27 #define CFUSB_ALIGNMENT 4 /* Number of bytes to align. */
28 #define CFUSB_MAX_HEADLEN (CFUSB_PAD_DESCR_SZ + CFUSB_ALIGNMENT-1)
29 #define STE_USB_VID 0x04cc /* USB Product ID for ST-Ericsson */
30 #define STE_USB_PID_CAIF 0x230f /* Product id for CAIF Modems */
32 struct cfusbl {
33 struct cflayer layer;
34 u8 tx_eth_hdr[ETH_HLEN];
37 static bool pack_added;
39 static int cfusbl_receive(struct cflayer *layr, struct cfpkt *pkt)
41 u8 hpad;
43 /* Remove padding. */
44 cfpkt_extr_head(pkt, &hpad, 1);
45 cfpkt_extr_head(pkt, NULL, hpad);
46 return layr->up->receive(layr->up, pkt);
49 static int cfusbl_transmit(struct cflayer *layr, struct cfpkt *pkt)
51 struct caif_payload_info *info;
52 u8 hpad;
53 u8 zeros[CFUSB_ALIGNMENT];
54 struct sk_buff *skb;
55 struct cfusbl *usbl = container_of(layr, struct cfusbl, layer);
57 skb = cfpkt_tonative(pkt);
59 skb_reset_network_header(skb);
60 skb->protocol = htons(ETH_P_IP);
62 info = cfpkt_info(pkt);
63 hpad = (info->hdr_len + CFUSB_PAD_DESCR_SZ) & (CFUSB_ALIGNMENT - 1);
65 if (skb_headroom(skb) < ETH_HLEN + CFUSB_PAD_DESCR_SZ + hpad) {
66 pr_warn("Headroom to small\n");
67 kfree_skb(skb);
68 return -EIO;
70 memset(zeros, 0, hpad);
72 cfpkt_add_head(pkt, zeros, hpad);
73 cfpkt_add_head(pkt, &hpad, 1);
74 cfpkt_add_head(pkt, usbl->tx_eth_hdr, sizeof(usbl->tx_eth_hdr));
75 return layr->dn->transmit(layr->dn, pkt);
78 static void cfusbl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
79 int phyid)
81 if (layr->up && layr->up->ctrlcmd)
82 layr->up->ctrlcmd(layr->up, ctrl, layr->id);
85 static struct cflayer *cfusbl_create(int phyid, u8 ethaddr[ETH_ALEN],
86 u8 braddr[ETH_ALEN])
88 struct cfusbl *this = kmalloc(sizeof(struct cfusbl), GFP_ATOMIC);
90 if (!this)
91 return NULL;
93 caif_assert(offsetof(struct cfusbl, layer) == 0);
95 memset(&this->layer, 0, sizeof(this->layer));
96 this->layer.receive = cfusbl_receive;
97 this->layer.transmit = cfusbl_transmit;
98 this->layer.ctrlcmd = cfusbl_ctrlcmd;
99 snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "usb%d", phyid);
100 this->layer.id = phyid;
103 * Construct TX ethernet header:
104 * 0-5 destination address
105 * 5-11 source address
106 * 12-13 protocol type
108 ether_addr_copy(&this->tx_eth_hdr[ETH_ALEN], braddr);
109 ether_addr_copy(&this->tx_eth_hdr[ETH_ALEN], ethaddr);
110 this->tx_eth_hdr[12] = cpu_to_be16(ETH_P_802_EX1) & 0xff;
111 this->tx_eth_hdr[13] = (cpu_to_be16(ETH_P_802_EX1) >> 8) & 0xff;
112 pr_debug("caif ethernet TX-header dst:%pM src:%pM type:%02x%02x\n",
113 this->tx_eth_hdr, this->tx_eth_hdr + ETH_ALEN,
114 this->tx_eth_hdr[12], this->tx_eth_hdr[13]);
116 return (struct cflayer *) this;
119 static struct packet_type caif_usb_type __read_mostly = {
120 .type = cpu_to_be16(ETH_P_802_EX1),
123 static int cfusbl_device_notify(struct notifier_block *me, unsigned long what,
124 void *ptr)
126 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
127 struct caif_dev_common common;
128 struct cflayer *layer, *link_support;
129 struct usbnet *usbnet;
130 struct usb_device *usbdev;
132 /* Check whether we have a NCM device, and find its VID/PID. */
133 if (!(dev->dev.parent && dev->dev.parent->driver &&
134 strcmp(dev->dev.parent->driver->name, "cdc_ncm") == 0))
135 return 0;
137 usbnet = netdev_priv(dev);
138 usbdev = usbnet->udev;
140 pr_debug("USB CDC NCM device VID:0x%4x PID:0x%4x\n",
141 le16_to_cpu(usbdev->descriptor.idVendor),
142 le16_to_cpu(usbdev->descriptor.idProduct));
144 /* Check for VID/PID that supports CAIF */
145 if (!(le16_to_cpu(usbdev->descriptor.idVendor) == STE_USB_VID &&
146 le16_to_cpu(usbdev->descriptor.idProduct) == STE_USB_PID_CAIF))
147 return 0;
149 if (what == NETDEV_UNREGISTER)
150 module_put(THIS_MODULE);
152 if (what != NETDEV_REGISTER)
153 return 0;
155 __module_get(THIS_MODULE);
157 memset(&common, 0, sizeof(common));
158 common.use_frag = false;
159 common.use_fcs = false;
160 common.use_stx = false;
161 common.link_select = CAIF_LINK_HIGH_BANDW;
162 common.flowctrl = NULL;
164 link_support = cfusbl_create(dev->ifindex, dev->dev_addr,
165 dev->broadcast);
167 if (!link_support)
168 return -ENOMEM;
170 if (dev->num_tx_queues > 1)
171 pr_warn("USB device uses more than one tx queue\n");
173 caif_enroll_dev(dev, &common, link_support, CFUSB_MAX_HEADLEN,
174 &layer, &caif_usb_type.func);
175 if (!pack_added)
176 dev_add_pack(&caif_usb_type);
177 pack_added = true;
179 strlcpy(layer->name, dev->name, sizeof(layer->name));
181 return 0;
184 static struct notifier_block caif_device_notifier = {
185 .notifier_call = cfusbl_device_notify,
186 .priority = 0,
189 static int __init cfusbl_init(void)
191 return register_netdevice_notifier(&caif_device_notifier);
194 static void __exit cfusbl_exit(void)
196 unregister_netdevice_notifier(&caif_device_notifier);
197 dev_remove_pack(&caif_usb_type);
200 module_init(cfusbl_init);
201 module_exit(cfusbl_exit);