1 /******************************************************************************
2  *  xusbatm.c -	dumb usbatm-based driver for modems initialized in userspace
3  *
4  *  Copyright (C) 2005 Duncan Sands, Roman Kagan (rkagan % mail ! ru)
5  *
6  *  This program is free software; you can redistribute it and/or modify it
7  *  under the terms of the GNU General Public License as published by the Free
8  *  Software Foundation; either version 2 of the License, or (at your option)
9  *  any later version.
10  *
11  *  This program is distributed in the hope that it will be useful, but WITHOUT
12  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  *  more details.
15  *
16  *  You should have received a copy of the GNU General Public License along with
17  *  this program; if not, write to the Free Software Foundation, Inc., 59
18  *  Temple Place - Suite 330, Boston, MA  02111-1307, USA.
19  *
20  ******************************************************************************/
21 
22 #include <linux/module.h>
23 #include <linux/etherdevice.h>		/* for random_ether_addr() */
24 
25 #include "usbatm.h"
26 
27 
28 #define XUSBATM_DRIVERS_MAX	8
29 
30 #define XUSBATM_PARM(name, type, parmtype, desc) \
31 	static type name[XUSBATM_DRIVERS_MAX]; \
32 	static unsigned int num_##name; \
33 	module_param_array(name, parmtype, &num_##name, 0444); \
34 	MODULE_PARM_DESC(name, desc)
35 
36 XUSBATM_PARM(vendor, unsigned short, ushort, "USB device vendor");
37 XUSBATM_PARM(product, unsigned short, ushort, "USB device product");
38 
39 XUSBATM_PARM(rx_endpoint, unsigned char, byte, "rx endpoint number");
40 XUSBATM_PARM(tx_endpoint, unsigned char, byte, "tx endpoint number");
41 XUSBATM_PARM(rx_padding, unsigned char, byte, "rx padding (default 0)");
42 XUSBATM_PARM(tx_padding, unsigned char, byte, "tx padding (default 0)");
43 XUSBATM_PARM(rx_altsetting, unsigned char, byte, "rx altsetting (default 0)");
44 XUSBATM_PARM(tx_altsetting, unsigned char, byte, "rx altsetting (default 0)");
45 
46 static const char xusbatm_driver_name[] = "xusbatm";
47 
48 static struct usbatm_driver xusbatm_drivers[XUSBATM_DRIVERS_MAX];
49 static struct usb_device_id xusbatm_usb_ids[XUSBATM_DRIVERS_MAX + 1];
50 static struct usb_driver xusbatm_usb_driver;
51 
xusbatm_find_intf(struct usb_device * usb_dev,int altsetting,u8 ep)52 static struct usb_interface *xusbatm_find_intf(struct usb_device *usb_dev, int altsetting, u8 ep)
53 {
54 	struct usb_host_interface *alt;
55 	struct usb_interface *intf;
56 	int i, j;
57 
58 	for (i = 0; i < usb_dev->actconfig->desc.bNumInterfaces; i++)
59 		if ((intf = usb_dev->actconfig->interface[i]) && (alt = usb_altnum_to_altsetting(intf, altsetting)))
60 			for (j = 0; j < alt->desc.bNumEndpoints; j++)
61 				if (alt->endpoint[j].desc.bEndpointAddress == ep)
62 					return intf;
63 	return NULL;
64 }
65 
xusbatm_capture_intf(struct usbatm_data * usbatm,struct usb_device * usb_dev,struct usb_interface * intf,int altsetting,int claim)66 static int xusbatm_capture_intf(struct usbatm_data *usbatm, struct usb_device *usb_dev,
67 		struct usb_interface *intf, int altsetting, int claim)
68 {
69 	int ifnum = intf->altsetting->desc.bInterfaceNumber;
70 	int ret;
71 
72 	if (claim && (ret = usb_driver_claim_interface(&xusbatm_usb_driver, intf, usbatm))) {
73 		usb_err(usbatm, "%s: failed to claim interface %2d (%d)!\n", __func__, ifnum, ret);
74 		return ret;
75 	}
76 	if ((ret = usb_set_interface(usb_dev, ifnum, altsetting))) {
77 		usb_err(usbatm, "%s: altsetting %2d for interface %2d failed (%d)!\n", __func__, altsetting, ifnum, ret);
78 		return ret;
79 	}
80 	return 0;
81 }
82 
xusbatm_release_intf(struct usb_device * usb_dev,struct usb_interface * intf,int claimed)83 static void xusbatm_release_intf(struct usb_device *usb_dev, struct usb_interface *intf, int claimed)
84 {
85 	if (claimed) {
86 		usb_set_intfdata(intf, NULL);
87 		usb_driver_release_interface(&xusbatm_usb_driver, intf);
88 	}
89 }
90 
xusbatm_bind(struct usbatm_data * usbatm,struct usb_interface * intf,const struct usb_device_id * id)91 static int xusbatm_bind(struct usbatm_data *usbatm,
92 			struct usb_interface *intf, const struct usb_device_id *id)
93 {
94 	struct usb_device *usb_dev = interface_to_usbdev(intf);
95 	int drv_ix = id - xusbatm_usb_ids;
96 	int rx_alt = rx_altsetting[drv_ix];
97 	int tx_alt = tx_altsetting[drv_ix];
98 	struct usb_interface *rx_intf = xusbatm_find_intf(usb_dev, rx_alt, rx_endpoint[drv_ix]);
99 	struct usb_interface *tx_intf = xusbatm_find_intf(usb_dev, tx_alt, tx_endpoint[drv_ix]);
100 	int ret;
101 
102 	usb_dbg(usbatm, "%s: binding driver %d: vendor %04x product %04x"
103 		" rx: ep %02x padd %d alt %2d tx: ep %02x padd %d alt %2d\n",
104 		__func__, drv_ix, vendor[drv_ix], product[drv_ix],
105 		rx_endpoint[drv_ix], rx_padding[drv_ix], rx_alt,
106 		tx_endpoint[drv_ix], tx_padding[drv_ix], tx_alt);
107 
108 	if (!rx_intf || !tx_intf) {
109 		if (!rx_intf)
110 			usb_dbg(usbatm, "%s: no interface contains endpoint %02x in altsetting %2d\n",
111 				__func__, rx_endpoint[drv_ix], rx_alt);
112 		if (!tx_intf)
113 			usb_dbg(usbatm, "%s: no interface contains endpoint %02x in altsetting %2d\n",
114 				__func__, tx_endpoint[drv_ix], tx_alt);
115 		return -ENODEV;
116 	}
117 
118 	if ((rx_intf != intf) && (tx_intf != intf))
119 		return -ENODEV;
120 
121 	if ((rx_intf == tx_intf) && (rx_alt != tx_alt)) {
122 		usb_err(usbatm, "%s: altsettings clash on interface %2d (%2d vs %2d)!\n", __func__,
123 				rx_intf->altsetting->desc.bInterfaceNumber, rx_alt, tx_alt);
124 		return -EINVAL;
125 	}
126 
127 	usb_dbg(usbatm, "%s: rx If#=%2d; tx If#=%2d\n", __func__,
128 			rx_intf->altsetting->desc.bInterfaceNumber,
129 			tx_intf->altsetting->desc.bInterfaceNumber);
130 
131 	if ((ret = xusbatm_capture_intf(usbatm, usb_dev, rx_intf, rx_alt, rx_intf != intf)))
132 		return ret;
133 
134 	if ((tx_intf != rx_intf) && (ret = xusbatm_capture_intf(usbatm, usb_dev, tx_intf, tx_alt, tx_intf != intf))) {
135 		xusbatm_release_intf(usb_dev, rx_intf, rx_intf != intf);
136 		return ret;
137 	}
138 
139 	return 0;
140 }
141 
xusbatm_unbind(struct usbatm_data * usbatm,struct usb_interface * intf)142 static void xusbatm_unbind(struct usbatm_data *usbatm,
143 			   struct usb_interface *intf)
144 {
145 	struct usb_device *usb_dev = interface_to_usbdev(intf);
146 	int i;
147 
148 	usb_dbg(usbatm, "%s entered\n", __func__);
149 
150 	for (i = 0; i < usb_dev->actconfig->desc.bNumInterfaces; i++) {
151 		struct usb_interface *cur_intf = usb_dev->actconfig->interface[i];
152 
153 		if (cur_intf && (usb_get_intfdata(cur_intf) == usbatm)) {
154 			usb_set_intfdata(cur_intf, NULL);
155 			usb_driver_release_interface(&xusbatm_usb_driver, cur_intf);
156 		}
157 	}
158 }
159 
xusbatm_atm_start(struct usbatm_data * usbatm,struct atm_dev * atm_dev)160 static int xusbatm_atm_start(struct usbatm_data *usbatm,
161 			     struct atm_dev *atm_dev)
162 {
163 	atm_dbg(usbatm, "%s entered\n", __func__);
164 
165 	/* use random MAC as we've no way to get it from the device */
166 	random_ether_addr(atm_dev->esi);
167 
168 	return 0;
169 }
170 
171 
xusbatm_usb_probe(struct usb_interface * intf,const struct usb_device_id * id)172 static int xusbatm_usb_probe(struct usb_interface *intf,
173 			     const struct usb_device_id *id)
174 {
175 	return usbatm_usb_probe(intf, id,
176 				xusbatm_drivers + (id - xusbatm_usb_ids));
177 }
178 
179 static struct usb_driver xusbatm_usb_driver = {
180 	.name		= xusbatm_driver_name,
181 	.probe		= xusbatm_usb_probe,
182 	.disconnect	= usbatm_usb_disconnect,
183 	.id_table	= xusbatm_usb_ids
184 };
185 
xusbatm_init(void)186 static int __init xusbatm_init(void)
187 {
188 	int i;
189 
190 	dbg("xusbatm_init");
191 
192 	if (!num_vendor ||
193 	    num_vendor != num_product ||
194 	    num_vendor != num_rx_endpoint ||
195 	    num_vendor != num_tx_endpoint) {
196 		printk(KERN_WARNING "xusbatm: malformed module parameters\n");
197 		return -EINVAL;
198 	}
199 
200 	for (i = 0; i < num_vendor; i++) {
201 		rx_endpoint[i] |= USB_DIR_IN;
202 		tx_endpoint[i] &= USB_ENDPOINT_NUMBER_MASK;
203 
204 		xusbatm_usb_ids[i].match_flags	= USB_DEVICE_ID_MATCH_DEVICE;
205 		xusbatm_usb_ids[i].idVendor	= vendor[i];
206 		xusbatm_usb_ids[i].idProduct	= product[i];
207 
208 		xusbatm_drivers[i].driver_name	= xusbatm_driver_name;
209 		xusbatm_drivers[i].bind		= xusbatm_bind;
210 		xusbatm_drivers[i].unbind	= xusbatm_unbind;
211 		xusbatm_drivers[i].atm_start	= xusbatm_atm_start;
212 		xusbatm_drivers[i].bulk_in	= rx_endpoint[i];
213 		xusbatm_drivers[i].bulk_out	= tx_endpoint[i];
214 		xusbatm_drivers[i].rx_padding	= rx_padding[i];
215 		xusbatm_drivers[i].tx_padding	= tx_padding[i];
216 	}
217 
218 	return usb_register(&xusbatm_usb_driver);
219 }
220 module_init(xusbatm_init);
221 
xusbatm_exit(void)222 static void __exit xusbatm_exit(void)
223 {
224 	dbg("xusbatm_exit entered");
225 
226 	usb_deregister(&xusbatm_usb_driver);
227 }
228 module_exit(xusbatm_exit);
229 
230 MODULE_AUTHOR("Roman Kagan, Duncan Sands");
231 MODULE_DESCRIPTION("Driver for USB ADSL modems initialized in userspace");
232 MODULE_LICENSE("GPL");
233 MODULE_VERSION("0.1");
234